HomeMy WebLinkAboutAPA3433VOLUME 9
ALAS!(.J\LJ::iJ 1.~)l::i'~:.:.-j .:~SA.r,/\E
333 R3sp::.sn-y Rd.
Anchorage,Aiaska 99518-1599
SIECTIONS 1 1'lIlIol~
EXHIBIT E
CHAPTER 3
BEFORE THE
FEDERAL ENERGY REGULATORY COMMISSION
APPLICATION FOR LICENSE FOR MAJOR PROJECT
SUSITNA HYDROELECTRIC PROJECT
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SUSITNA JOINT VENTURE
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NOTICE
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A NOTATIONAL SYSTEM HAS BEEN USED
TO DENOTE DIFFERENCES BETWEEN THIS AMENDED LICENSE APPLICATION
AND
THE LICENSE APPLICATION AS ACCEPTED FOR FILING BY FERC
ON JULY 29,1983
This system consists of placing one of the following notations
beside each text heading:
(0)No change was made in this section,it remains the same as
was presented in the July 29,1983 License Application
(*)Only minor changes,largely of an editorial nature,have been
made
(**)Major changes have been made in this section
(***)This is an entirely new section which did not appear in the
July 29,1983 License Application
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VOLUME COMPARISON
VOLUME NUMBER COMPARISON
LICENSE APPLICATION AMENDMENT VSo JULY 29,1983 LICENSE APPLICATION
JULY 29,1983
AMENDMENT APPLICATION
VOLUME NO.VOLUME NO.
j
EXHIBIT CHAPTER
A Entire
DESCRIPTION
Project Description 1 1
B
C
D
Entire
App.Bl
App.B2
App.B3
Entire
Entire
App.Dl
Pr9j~ct 9peration and Resource
Ut 1.11.za t1.on
MAP Model Documentation Report
RED Model Documentation Report
RED Model Update
Proposed Construction
Schedule
Project Costs and Financing
Fuels Pricing
2
3
4
4
S
S
5
2 &2A
2B
2C
1
1
1
E 1
2
Tables
Figures
Figures
3
General Description of Locale 6
Water Use and Quality 6
7
8
Fish,Wildlife and Botanical 9
Resources (Sect.land 2)
SA
5A
SA
SB
5B
6A
6B
Fish,Wildlife and Botanical
Resources (Sect.3)
Fish,Wildlife and Botanical
Resources (Sect.4,5,6,&7)
10
11
6A
6B
6A
6B
4
5
6
Historic &Archaeological Resources 12
Socioeconomic Impacts 12
Geological and Soil Resources 12
7
7
7
F
F
G
7
8
9
10
11
Entire
Entire
Entire
Recreational Resources
Aesthetic Resources
Land Use
Alternative Locations,Designs
and Energy Sources
Agency Consultation
Project Design Plates
Supporting Design Report
Project LJ.m1.tsand Land OwnershJ.p
Plates
13
13
13
14
14
15
16
17
8
8
8
9
lOA
lOB
3
4
SUMMARY TABLE OF CONTENTS
SUSITNA HYDROELECTRIC PROJECT
LICENSE APPLICATION
SUMMARY TABLE OF CONTENTS
EXHIBIT A
PROJECT DESCRIPTION
A-2-1
A-1-2
A-1-4
A-1-6
A-I-9
A-1-10
A-l-13
A-1-15
A-I-IS
A-1-l8
A-1-19
A-1-22
A-1-23
A-1-25
A-1-29
A-1-2
Page No.
· .
·.
·.
O'10 0
o .::'8 •
....
Cl • • •e Cl
••
. . .
e 0 III 0
. .
1.1 -General Arrangement (**)••
1.2 -Dam Embankment (**)•••
1.3 -Diversion (**).
1.4 -Emergency Release Facilities (**)
1.5 -Outlet Facilities (**)•••••••••
1.6 -Spillway (**)••••
1.7 -This section deleted ••
1.8 -Power Intake (**)•••
1.9 -Power Tunnels and Penstocks (**)
1.10 -Powerhouse (**)••••
1.11 -Tailrace (**)• •••••••
1.12 -Main Access Plan (**)••••
1.13 Site Facilities (**).
1.14 -Relict Channel (***)
2 -RESERVOIR DATA -WATANA STAGE I (**)
Title
1 -PROJECT STRUCTURES -WATANA STAGE I (**)
3 -TURBINES AND GENERATORS -WATANA STAGE I (**)•GI 0 Q Cl A-3-1
3.1 -Unit Capacity (**)••••
3.2 -Turbines (***)••••••••••••••••••
3.3 -Generators (**)• • • •
3.4 -Governor System (0)••••
A-3-1
A-3-1
A-3-1
A-3-3
4 -APPURTENANT MECHANICAL AND ELECTRICAL EQUIPMENT -
WATANA STAGE I (**)•••••••••••••••• • •
A-4-1
4.1 -Miscellaneous Mechanical Equipment (**)
4.2 -Accessory Electrical Equipment (**)•••
4.3 -SF6 Gas-Insulated 345 kV Substation (GIS)(***)
A-4-1
A-4-5
A-4-12
5 -TRANSMISSION FACILITIES FOR WATANA STAGE I (0)•••o ..A-5-1
5.1 -Transmission Requirements (0)
5.2 -Description of Facilities (0)
5.3 -Construction Staging (0)•••
A-5-1
A-5-1
A-5-11
851014 i
SUMMARY TABLE OF CONTENTS (cont'd)
9.1 -scellaneous Mechanical Equipment (0)• • • • • •A-9-1
9.2 -Accessory Electrical Equipment (o)=--=----=--=-~-----A"':9-=:f-
9.3 -Switchyard Structures and Equipment (0).••A-9-6
8 -TURBINES AND GENERA'.l'ORS....DEVILCANYON STAGE II{**.).-.
EXHIBIT A
PROJECT DESCRIPTION
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A-6-12
A-6-13
A-6-14
A-6-17
A-6-17
A-6-18
A-7-1
A-8-l
A-6-1
A-9-1
A-6-1
A-6-2
A-6-4
A-6-6
A-6-8
A-6-10
A-6-12
A-8-1
A-8-1
A-8-1
A-8-2
A-Il-l
A-1l-3
A-11-5
A-1l-6
A-lO-l
A-ll-l
Page No.
• •
• • •
Co ..0 •
••
...
o 0 • ••0 0 • 0 •
ii
•Cl ••
. ... . ....
o ••GOO •.00
11.1 -General Arrangement (***)•••-.•••••••
n.2 ;,.,·Dam Embankment (***)• • • •• • • •
11.3 -Diversion (***)••••••••••••
11.4 -Emergency Release Facilities (***)••
8.1 -Unit Capacity (**)•
8.2 -Turbines (**)•••
8.3 -Generators (0)•••
8.4 -Governor System (0)
6.1 -General Arrangement (**)•••••••••••••
6.2 -Arch Dam (**)• ••••••
6.3 -Saddle Dam (**)• • • •••••
6.4 -Diversion (**)• • • • • • • • • ••••
6.5 -Outlet Facilities (**)• • • • • • • • •••
6.6 -Spillway (**)••••••••••••
6.7 --Emergency spi 11 way • • • • • • • • • • • • • •
(This section deleted)
6.8 -Power Facilities (*)• • • • • • •••
6.9 -Penstocks (**)• • • • •• • • • • • • • •
6.10 -Powerhouse and Related Structures (**).-.
6.11 -Tailrace Tunnel (*)•• • • • ••••
6.12 -Access Plan (**)••.•.
6.13 -Site Facilities (*)•
Title
10 -TRANSMISSION LINES -DEVIL CANYON STAGE II (**)
7 -DEVIL CANYON RESERVOIR STAGE II (*)
11 -PROJECT STRUCTURES -WATANA STAGE III (*'h\')
6 -PROJECT STRUCTURES -DEVIL CANYON STAGE II (**)
851014
9 ,...APPURTENANT EQUIPMENT -DEVIL CANYON STAGE II (0)••
SUMMARY TABLE OF CONTENTS (cont I d)
EXHIBIT A
PROJECT DESCRIPTION
Title Page No.
11.5 -Outlet Facilities (***)
11.6 -Spillway (***)•••••
11.7 -Power Intake (***)••••
11.8 -Power Tunnel and Penstocks
11.9 -Powerhouse (***)•••••
11.10 -Trailrace (***)• • • •
11.11 -Access Plan (***)••
11.12 -Site Facilities (***)•
11.13 -Relict Channel (***)
D 0 0 • • 0 0 e 0
...
(***)•
(II • •0 • •
•••0 •
A-1l-6
A-1l-7
A-1l-8
A-ll-ll
A-ll-ll
A-ll-13
A-1l-13
A-ll-13
A-ll-13
12 -RESERVOIR DATA -WATANA STAGE III (***)o • •e CD 0 ·.A-12-1
... .. .
13 -TURBINES AND GENERATORS -WATANA STAGE III (***)
13.1 -Unit Capacity (***)•
13.2 -Turbines (***)
13.3 -Generators (***)
13.4 -Governor System (***)
14 -APPURTENANT MECHANICAL AND ELECTRICAL EQUIPMENT -
WATANA STAGE III (***)••••••••••••••
14.1 -Miscellaneous Mechanical Equipment (***).
14.2 -Accessory Electrical Equipment (***)•.••
·.
·.
A-13-1
A-13-1
A-13-1
A-13-1
A-13-1
A-14-1
A-14-1
A-14-1
15 -TRANSMISSION FACILITIES -WATANA STAGE III (***)
15.1 Transmission Requirements (***)•
15.2 switching and Substations (***)
.. .
..
A-15-1
A-15-1
A-15-1
16 -LANDS OF THE UNITED STATES (**)o e G ••0 • • 0 • •A-16-1
17 -REFERENCES
851014
00.• • • ••• •e _ •e _e • •
iii
·.A-17-1
SUMMARY TABLE OF CONTENTS (cant I d)
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B-l-l
B-l-12
B-l-17
B-2-1
B-3-1
B-I-1
B-1-4
B-1-S
B~2-1
B-2-1
B-2-22
B-2-48
B-4-1
B-3-1
B-3-6
B-3-20
B-4-1
B-4-10
B-S-1
B-7-1
B-6-1
B"'5-1
B-5-1
13=S"'17
B-5-47
Page No.
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EXHIBIT B
PROJECT OPERATION AND RESOURCE UTILIZATION
1.1 -Previous Studies (***)•••••
1.2 -Plan Formulation and Selection Methodology (***).
1.3 -Damsite Selection (***)••••••••••
1.4 -Formulation of Susitna Basin Development
Plans (***)• • • • • ••.• • •
1.S -Evaluation of Basin Development Plans (***)
3.1 -Hydrology (***)• • • • • ••••
3.2 -Reservoir Operation Modeling (***)
3.3 -Operational Flow Regime Selection (***')
2.1 -Susitna Hydroelectric.Development {***>•
2.2 -Watana Project Formulation (***)•••••
2.3 -Selection of Watana General Arrangement (***)
2.4 -Devil Canyon Project Formulation (***).
2.5 -Selection of Devil Canyon General
Arrangement (***)• • • • • • • • • • • •B-2-60
2.6 -Selection of Access Road Corridor (***)B-2-67
2.7-Selection of-TransmissionFaciclities~(-*.*,*~-••--•.-•.-B..,,2 .....83
2.8 -Selection of Project Operation (***)B-2-131
S.l -Introduction (***)••••••••••••
S.2 -Description of the Railbelt Electric Systems (***)
5.3 -Forecasting Methodology (***)~..• • • • •
S.4 -Forecast of Electric Power Demand (***)
4.1 -Plant and System Operation Requirements (***)
4.2 -Power and Energy Production (***)• •..•
-POWER AND ENERGY PRODUCTION ••• •..•••....•
..-----_...._.._-_.._----------------------_.__..----_.-
2 -ALTERNATIVE FACILITY DESIGN,PROCESSES AND
OPERATIONS (ir**).....••• • •0 ..""•
3 -DESCRIPTION OF PROJECT OPERATION (***)
S -STATEMENT OF POWER NEEDS AND UTILIZATION (***)
Title
1 -DAMSITE SELECTION (***)
851014
7 -REFERENCES
6 -FUTURE SUSITNA BASIN DEVELOPMENT (***)
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT B -APPENDIX BI
MAN-IN-THE-ARCTIC PROGRAM (MAP)
TECHNICAL DOCUMENTATION REPORT
STAGE MODEL (VERSION A85.1)
REGIONALIZATION MODEL (VERSION A84.CD)
SCENARIO GENERATOR
Title Page No.
Stage Model
1-1
2-1
3-1
4-1
5-1
6-1
7-1
8-1
9-1
10-1
11-1
12-1
13-1
·.
o o'0
· ..· ..· .
.,•0
Introduction •• • • • • • • • • • • • • • • •
Economic Module Description
Fiscal Module Description
Demographic Module Description •
Input Variables .;:b.......
Variable and Parameter Name Conventions
Parameter Values,Definitions and Sources
Model Validation and Properties
Input Data Sources • • • • • • • • • • •
Programs for Model Use • • • • • • • • •
Model Adjustments for Simulation •
Key to Regressions • •
Input Data Archives • • • • • • • • • •
L
2.
3.
4.
5.
6.
7.
8.
9.
10.
1L
12.
13.
Regionalization Model
1.Model Description ····1
2.Flow Diagram ..··.··.·.·.5
3.Model Inputs ..··· ·
7
4.Variable and Parameter Names ···9
5.Parameter Values ···· ·
···13
6.Model Validation ···.· · · ··31
7.Programs for Model ·38
8.Model Listing ···39
9.Model Parameters ··.·· ··· ·····..·.57
10.Exogenous,Policy,and Startup Values · ···.61
Scenario Generator
· .
Introduction . . . . . . . . . . . . ..0 • •0 • • • • •
1.Organization of the Library Archives ••
2.Using t):le Scenario Generator • • • • • • • • • • • • •
3.Creating,Manipulating,Examining,and
Printing Library Files • •
4.Model Output • • • • • • • • • • • • • • •
1
1
8
14
22
851014 v
SUMMARY TABLE OF CONTE'NTS(cont'd)
EXHIBIT B -APPENDIX B2
RAILBELT ELECTRICITY DEMAND (RED)MODEL
TECHNICAL DOCUMENTATION REPORT (1983 VERSION)
7 -PRICE ELASTICITY •0 • • • • 0 • • •
8·-THE PROGRAM-INDUCED CONSERVATION MODULE
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Page No.]
1.1
2.1 ]
3.1 I
4.1
5.1 1
6.1
!.1
8.1 I
9.1
10.1 I
11.1
112.1
13.1
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• •.0.•0 ••
o e 0 0 • 0 •0
•0
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11 -THE PEAK DEMAND MODULE
10 -LARGE INDUSTRIAL DEMAND
5 -THE RESIDENTIAL CONSUMPTION MODULE •
12 -MODEL VALIDATION • • •
13 -MISCELLANEOUS TABLES
2 -OVERVIEW • •
1 -INTRODUCTION •
Title
3 -UNCERTAINTY MODULE •
4 -THE HOUSING MODULE •
851014
9 -THE MISCELLANEOUS MODULE
6 -THE BUSINESS CONSUMPTION MODULE • •or:..•
SUMMARY TABLE OF CONTENTS (cant'd)
EXHIBIT B -APPENDIX B3
RAILBELT ELECTRICITY DEMAND (RED)MODEL
CHANGES MADE JULy 1983 TO AUGUST 1985
Title Page No.
1 -INTRODUCTION o 0 e eo.•1.1
2 -RED MODEL PRICE ADJUSTMENT REVISIONS 2.1
3 -RESIDENTIAL CONSUMPTION MODULE . . .3.1
4 -BUSINESS SECTOR
5 -PEAK DEMAND
Cl • • •
•Cl • •
o DOC GOG 4.1
5.1
6 -EFFECT OF THE MODEL CHANGES ON THE FORECASTS •6.1
851014 vii
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT C
PROPOSED CONSTRUCTION SCHEDULE
2.1 -Access (**)• • • • • • •••
2.2 -Site Facilities (**)••••
2.3 -Diversion (*)••••••••••-••••••••
2.4 -Arch Dam (**)• • • • • •••••
2.5 -Spillway and Intake (*)•••••••••
2~6":-"Powerhouse"aiidOtherundergI:ound~WOrks"ro)
2.7 -Transmission Lines/Switchyards (*)••••
2.8 -General (*)'••••
1.1 -Access (*).• • ••••••
1.2 -Site Facilities (**)••••••
1.3 -Diversion (**)••••••••••••
1.4 -Dam Embankment (**)• • • • • • • • • •
1.5 -Spillway and Intakes (**)••••
1.6 -Powerhouse and Other Underground Works (**)
1.7 -Relict Channel (**)• • • • • • • • ••••
1.8 -Transmission Lines/Switchyards (*)
1.9 -Gen$ral"(**)•••••••••••••••
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C-2-1
C-1-2
C-1-2
C-1-2
C-1-2
C-1-3
C-1-3
C-1-3
C-1-3
C-1-3,
C-I-I
C-2-1
C-2-1
C-2-1
C-2-1
C-2-2----_.........•_._-_.__.._----
C-2-2
C-2-2
C-2-2
Page No.
""• • •e"""
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2 -DEVI.:L cANYON STAGE II SCHEDtJLE (*'*)0
1 -WATANA STAGE I SCHEDULE (**)
Title
3.1 -Access (***)• • • • • • •C-3-1
3.2 -Site Facilities (***)• • • •••••••C-3-1
-3.;;3 ...DamEmbankm$ut--(***)-----"""~-.C;;;;3:;,;;-1
~-""""~"-~----~----""--------""~3.4----Spi-Hway-and-Int-akes-(***}-"--.-.-.-"-.-.""..----.-.--;---';-----C-1-2-----------
3.5 -Powerhouse and Other Underground Works (**)•C-3-2
3.6 -Relict Channel (***)......".• •••C-3-2
3.7 -Transmission Lines/Swicchyards (***)••••••C-3-2
3.8 -General (***)• • • • • • • • • • • • • •••C-3-2
o G •0 •e 0 0 G •
3 -WATANA STAGE III SCHEDULE (***)"e e "
4 -EXISTING TRANSMISSION SYSTEM (***)
"."e """"C-3-1
C-4-1
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851014 viii r
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT D
PROJECT COSTS AND FINANCING
Title Page No.
1 -ESTIMATES OF COST (**)
. .1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
.0.• • • • 0 • • • • •e • •
-Construction.Costs (**)•••••
-Mitigation Costs (**)• •
-Engineering and Administration Costs (*)
-Operation,Maint'enance and Replacement Costs (**)
-Allowance for Funds Used During
Construction (AFDC)(**)••••••••••••
-Escalation (**)• • • • • • • • • • • • • •
-Cash Flow and Manpower Loading Requirements (**).
-Contingency (*)••••••••••••••
-Previously Constructed Project Facilities (*)••
D-l-l
D-l-l
D-1-6
D-1-7
D-I-I0
D-l-11
D-1-12
D-r-12
D-1-13
D-1-13
2 -EVALUATION OF ALTERNATIVE EXPANSION PLANS (***)•...D-2-1
. .
2.1 -General (***)••••••••••
2.2 -Hydroelectric Alternatives (***)
2.3.-Thermal Alternatives (***)
2.4 -Natural Gas-Fired Options.(***)•
2.5 -Coal-Fired Options (***)•••••••••
2.6 -The Existing Railbelt Systems (***)••
2.7 -Generation Expansion Before 1996 (***)
2.8 -Formulation of Expansion Plans Beginning in
1996 (*"**)e 8 •..• • • "Q ..0 '"CI • 0 •'"••
2.9 Selection of Expansion Plans (***)
2.10 -Economic Development (***)• • • • • • • • • • •
2.11 -Sensitivity Analysis (***)
2.12 -Conclusions (***)••••••••
D-2-1
D-2-1
D-2-10
D-2-10
D-2-19
D-2-24
D-2-27
D-2-28
D-2-33
D-2-39
D-2-44
D-2-46
3 -CONSEQUENCES OF LICENSE DENIAL (***)o • • •~•Q •e D-3-1
3.1 -Statement and Evaluation of the
Consequences of License Denial (***).
3.2 -Future Use of the Damsites if
the License is Denied (***)
4 -FINANCING (***)• • • • • •0 • • • • • 0 • •
4.1 -General Approach and Procedures (***)•
4.2 Financing Plan (***)••••
4.3 -Annual Costs (***)••••••••••
.."...
•• • ••
D-3-1
D-3-1
D-4-1
D-4-1
D-4-1
D-4-3
851014 ix
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT D
PROJECT COSTS AND FINANCING
• •o·0 • •e •e 0 0 •e e • •0 ••
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D-5-1
D-4-4
D-4-4
D-4-4
Page No.
0110 e
e III 0 000
DOD G 0 COG
x
4.4 -Market Value of Power (***)•
4.5 -Rate Stabilization (***)••
4.6 -Sensitivity of Analyses (***)
Title
5 -REFERENCES (***)
851014
.SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT D -APPENDIX Dl
FUELS PRICING
Title Page No.
e • •0 0 e 0 c • • •e e •coo •1 -INTRODUCTION (***')
2 -WORLD OIL PRICE (***')•...-..••.....0...
Dl-1-1
D1-2-1
D1-3-l
Dl-2-1
Dl-2-2
D1-2-5
...
o .0 •
•• •
...•••C De.
2.1 -The Sherman H.Clark Associates Forecast (***)
2.2 The Composite Oil Price Forecast (***)
2.3 -The Wharton Forecast (***)
3 -NATURAL GAS (***)••".• •
3.1 -Cook Inlet Gas Prices (***)• • • • •••Dl-3-l
3.2 -Regulatory Constraints on the Availability of
Natural Gas (***)• . • • • • • • • • • • •Dl-3-10
3.3 -Physical Constraints on the Availability of
Cook Inlet Natural Gas Supply (***). • • •D1-3-12
3.4 -North Slope Natural Gas (***)•••D1-3-20
4 -COAL (***)o •••••••eo •0 0 0 &)0 •eGG •0 •D1-4-l
4.1 -Resources and Reserves (***)••••••••
4.2 -Demand and Supply (***)• • • • • • ••••
4.3 -Present and Potential Alaska Coal Prices (***)
4.4 -Alaska Coal Prices Summarized (***)•
D1-4-1
Dl-4-3
D1-4-4
Dl-4-10
• •••eo.•a 0 0 0 •0 ••05 -DISTILLATE.OIL (***)
5.1 -Availability (***)••
5.2 -Distillate Price (***)
••. .
.... . . . . .
D1-5-1
D1-5-1
D1-5-1
6 -REFERENCES • • • • • 0 e,e 6 •••0 •0 • • 0 &0 ••Dl-6-1
851014 xi
SUMMARY TABLE OF CONTENTS (cant t d)
EXHIBIT E -CHAPTER 1
GENERAL DESCRIPTION OF THE LOCALE
Title Page No.
1 -GENERAL DESCRIPTION (*)"""••0 •0 0 G Q.0 0 e e 0 E-1-1-1
1.1 -General Setting (**)
1.2 -Susitna Basin (*)
3 -GLOSSARY ""
2 -REFERENCES
,851014
••0 •Q •e ••
•e 0 ceo 0 e
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.00 ~•••eo.0·.e
xii
E-1-1-1
E-1-1-2
E-1-2-1
E-1-3-1
\-
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SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 2
WATER USE AND QUALITY
Title
1 -INTRODUCTION (**)• • • • ••••.•0 •e e Q •0 C>G 0
Page No.
E-2-1-1
2 -BASELINE DESCRIPTION (**)•• • ••.00 • 0
•lD 0 •.,E-2-2-1
. .
. ..
2.1 -Susitna River Morphology(**)••
2.2 -Susitna River Water Quantity (**)••••
2.3 -Susitna River Water Quality (**).
2.4 -Baseline GroundWater Conditions (**)••••'••
2.5 -Existing Lakes,Reservoirs,and Streams (**)
2.6 -Existing Instream Flow Uses (0)•••
2.7 -Access Plan (**)••••••••••••••••
2.8 -Transmission Corridor (**)•••••
E-2-2-3
E-2-2-12
E-2-2-19
E-2-2-46
E-2-2-49
E-2-2-50
E-2-2-63
E-2-2-64
3 -OPERATIONAL FLOW REGIME SELECTION (***)• 0 .........E-2-3-1
3.1 -Project Reservoir Characteristics (***)••
3.2 -Reservoir Operation Modeling (***)••
3.3 -Development of Alternative Environmental
Flow Cases (***)•••••••••••••
3.4 -Detailed Di~cussion of Flow Cases-(***)•
3.5 -Comparison of Aiternative Flow Regimes (***).
3.6 -Other Constraints on Project Operation (***)
3.7 -Power and Energy Production (***)•••••
E-2-3-1
E-2-3-2
,E-2-3-6
E-2-3-17
E-2-3-37
E-2-3-43
E-2-3-53
4 -PROJECT IMPACT ON WATER QUALITY AND QUANTITY (**)•••E-2-4-1
4.1 -Watana D~velopment (**)••••••••
4.2 -Devil Canyon Development (**)•••
4.3 -Watana Stage III Development (***).
4.4 -Access Plan (**)••••••••••
E-2-4-7
E-2-4-110
E-2-4-160
E-2-4-211
5 -AGENCY CONCERNS .AND RECOMMENDATIONS (**)••0 •co.E-2-5-1
6 -MITIGATION,ENHANCEMENT,AND PROTECTIVE MEASURES (**)•
6.1 -Introduction (*)••••••••••••••••
6.2 -Mitigation -Watana Stage I -Construction (**)
6.3 -Mitigation -Watana Stage I -Impoundment (**)••
E-2-6-1
E-2-6-1
E-2-6-1
E-2-6-5
851014 xiii
851014
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E-2-7-1
E-2-6-13
E-2-6-15
E-2-6-13
E-2-6-13
E-2-6-7
E-2-6-16
E-2-6-16
E-2-6-18
Page No.
.0.e ••• • •0 • •~•••••0 0 0 •
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT.E -CHAPTER 2
WATER USE AND QUALITY
-Watana Stage I Operation (**)•
-Mitigation -Devil Canyon Stage II -
Construction (**)• • • • • • •
-Mitigation -Devil Canyon Stage II -
Impoundment (**)••••••••••••••••
-Mitigation -Devil Canyon/Watana Operation (**)•
-Mitigation -Watana Stage III -
Gonstruction (***)..
-Mitigation -Wata~Stage III -
Impoundment/Construction (***)
-Mitigation -Stage II~~Operation (***)
-Access Road:and Transmission Lines (***)
6.9
6.10
6.11
6.7
6.8
6.6
Title
7 -REFERENCES
8 -GLOSSARY ..........e •..-....e e.0 e ....• •.........E-2-8-1
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,AND BOTANICAL RESOURCES
1.1 -Baseline Descriptions (0)•
1.2 -Impact Assessments (*)
1.3 -Mitigation Plans (*)
Title
1 -INTRODUCTION (0). ...o •Cl •
.. .
Page No.
E-3-1-1
E-3-1-1
E-3-1-1
E-3-1-3
. .
2 -FISH RESOURCES OF THE SUSITNA RIVER DRAINAGE (**)•• •
2.1 -Overview of the Resources (**)•••••••
2.2 -Species Biology and Habitat Utilization
in the Susitna River DrainageJ (*)••• •
2.3 -Anticipated Impacts To Aquatic Habitat (**)
2.4 -Mitigation Issues and Mitigating Measures (**)
2.5 -Aquatic Studies Program (*)• •••••
2.6 -Monitoring Studies (**)•••••••••••••
2.7 -Cost of Mitigation (***)•••••••••
2.8 -Agency Consultation on Fisheries Mitigation
Measures (**)• • •
E-3-2-1
E-3-2-1
E-3-2-14
E-3-2-104
E-3-2-244
E-3-2-279
E-3-2-280
E-3-2-303
E-3-2-304
3 -BOTANICAL RESOURCES (**).••••0 ••00 ••••••E-3-3-1
3.1 -Introduction (*)••
3.2 -Baseline Description (**)
3.3 -Impacts (**)••••
3.4 -Mitigation Plan (**)
4 -WILDLIFE (**)••••• •
..
.....•CD •••• •
...
E-3-3-1
E-3-3-6
E-3-3-34
E-3-3-63
E-3-4-1
4.1 -Introduction (*).•.•
4.2 -Baseline Description (**)
4.3 -Impacts (*)..•••.••••••••.
4.4 -Mitigation Plan (**)••••••••
E-3-4-1
E-3-4-3
E-3-4-110
E-3-4-248
5.1 -Introduction (***)••••••••••••
5.2 -Existing Conditions (***)• ••••
5.3 -Expected Air Pollutant Emissions (***)•••
5.4 -Predicted Air Quality Impacts (***)••••
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......
. ..
E-3-5-1
E-3-5-1
E-3-5-1
E-3-5-2
E-3-5-3
851014 xv
SUMMARY TABLE OF CONTENTS (cont'd)
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E-3-6-1
E-3-5-3
Page No.
•••...••••
METHODS USED TO DETERMINE MOOSE BROWSE UTILIZATION
AND CARRYING CAPACITY WITHIN THE MIDDLE SUSITNABASIN
STATUS,HABITAT USE AND RELATIVE ABUNDANCE OF BIRD
SPECIES IN THE MIDDLE SUSITNA BASIN
EXISTING AIR QUALITY AND METEOROLOGICAL CONDITIONS
PLANT SPECIES IDENTIFIED IN SUMMERS OF 1980 AND 1981
IN THE UPPER AND MIDDLE SUSITNA RIVER BASIN,THE
DOWNSTREAM FLOODPLAIN,AND THE IN·TERTIE
PERSONAL COMMUNICATIONS (THIS SECTION HAS BEEN
DELETED)
EXPLANATION ANl;t JUSTIF.ICATIONOFARTIFICIALNEST
MITIGATION (THIS SECTION HAS .BEEN DELETED)
FISH AND WILDLIFE MITIGATION POLICY
ENVIRONMENTAL GUIDELINES MEMORANDUM
(THIS APPENDIX HAS BEEN DELETED)
PRELIMINARY LIST OF PLANT SPECIES IN THE INTERTIE
AREA (THIS SECTION HAS BEEN DELETED AND ITS'
·lNF()lU-fATION-INCOIU'OJ.tATE]:f·n(TO~Al'PEND:tX .Ir3:~3:T
• •0 0 •••
• • 0 • • • • • •0 ••0 0 0 •&e 0 0 •e 0
5.5 -Regulatory Agency Consultations (***)•
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,AND BOTANICAL RESOURCES
6 -REFERENCE •
El1.3
E6.3
E8.3
ElO.3
E2.3
E4.3
E1.3
E9.3
APPENDICES
851014
E5.3
Title
E3.3
7 -'GLOSSARY
STATUS AND RELATIVE ABUNDANCE OF BIRD SPECIES
OBSERVED ON THE LOWER SUSITNA BASIN DURING GROUND
SURVEYS CONDUCTED JUNE 10 THE JUNE 20,1982
....."..
.---··-·------------E-7-.-3---------------SCI-EN'r-I-F-IG-NAMES--QF-MAMMAL-SPECI-ES-FQUND--IN-'J.!HE---------:-
PROJECT AREA
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 4
HISTORIC AND ARCHEOLOGICAL RESOURCES
Title
1 -INTRODUCTION AND SUMMARY (**)••co ....co • •• • • 0
Page No.
E-4-1-1
1.1 -Program Objectives (**)•
1.2 -Program Specifics (**)••••
E-4-1-4
E-4-1-4
2 -BASELINE DESCRIPTION (**)...•GO.••...0.• •
E-4-2-1
'..2.1 -The Study Area (**)• • • • • •
2.2 -Methods -Archeology and History (**)•
2.3 -Methods -Geoarcheology (**)• ••
2.4 -Known Archeological and Historic
Sites in the Project.Area (**)
2.5 -Geoarcheology'(**)•••••••••••••••
E-4-2-1
E-4-2-2
E-4-2-10
E-4-2-12
E-4-2-13
3 -EVALUATION OF AND IMPACT ON HISTORICAL
AND ARCHEOLOGICAL SITES (**)•••••• • • •'.• • 0
E-4-3-1
3.1 -Evaluation of Selected Sites Found:
Prehistory and History of the Middle
Susitna Region (**)• •••• •••• ••.• •••E-4-3-1
3.2 -Impact on Historic and Archeological Sites (**)•E-4-3-4
4 -MITIGATION OF IMPACT ON HISTORIC AND
ARCHEOLOGICAL SITES(**)•co •• • • • o co •co • •
.00 E-4-4-1
4.1 -Mitigation Policy and Approach (**)•
4.2 -Mitigation Plan (**)••••
.00 . ..E-4-4-1
E-4-4-2
5 -AGENCY CONSULTATION (**)• • 0 • •••0 •e e &•0 0 E-4-S-1
J
I
6 -REFERENCES
7 -GLOSSARY
851014
• • ••• • 0 • • • • • • •D • 0 0 ••••
• • • • e • •e"• • • • • •e _••0 •• • •
xvii
E-4-6-1
E-4-7-1
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E-CHAPTER 5
SOCIOECONOMIC IMPACTS
Title Page No.
~--1 ~
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E-5-2-1
E-5-3-35
E-5-1-1
E-5-2-1
E-5-3-39
E-5-3-2
E-5-3-32
E-5-3-65
E-5-3-1
E-5-3-59
E-5-4-2
••0
••0
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••0
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.0·0908
•••• •
----;:----._-------~-~~----------------------------~--:------:------
-Introduction (**)• • ••• • • • • • • •••E-5-4-1
-Background and Approach (**)•••E-5~4-1
-Attitudes Toward Changes • ••• •E-5-4-2
(This section deleted)
-Mitigation Objectives and Measures (**)
BASELINE·DESCRIPTION (**)
4.1
4.2
4.3
4.4
2
3 -EVALUATION OF THE IMPACT OF THE PROJECT (**)
1 -INTRODUCTION (**)• ••• • •
851014
2.1 -Identification of Socioeconomic
Impact Areas (**)• • • • • • • • • • • • • • • •
2.2 -Description of Employment,Population,Personal
Income and Other Trends in the Impact Areas (**)
3.1 -Impact of In-migration of People on Governmental
Facilities and Services (**)••-ii.-•••00
302 -On-site Worker Requirements and Payroll,
by Year and Month (**)•••0 • • • • • • • • 0
3.3 -Residency and Movement of Project Construction
Personn~l (**)• • •0
3.4 -Adequacy of Available Housing in
Impact Areas (***)•••••••• • • •
~~--~--3·.·5~-Di.splacement--and-Influences~on~~Residences-and
Businesses''(**)•••' • • • • • • ••.••
3.6 -Fiscal Impact Analysis:Evaluation of'
Incrementa~Local Government Expenditures
and Revenues (**)• • • • ••• •
3.7 -Local and Regional Impacts on
Resource User Groups (**)• •••
..---"
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 5
SOCIOECONOMIC IMPACTS
Title
5 -MITIGATION MEASURES RECOMMENDED BY AGENCIES(**)....
Page No.
E-5-5-1
. .
5.1 -Alaska Department of Natural Resources (DNR)(**)
5.2 -Alaska Department of Fish and Game (ADF&G)(*)
5.3 -u.s.Fish and Wildlife .Service (FWS)(*)
5.4 -Summary of Agencies'Suggestions for Further
Studies that Relate to Mitigation (**)•••
E-5-5-1
E-5-5-1
E-5-5-2
E-5-5-2
6 -REFERENCES
851014
O~O •.•••••••-0 0 a •0 •0 e 0 ~
xix
••E-6-6-1
SUMMARY TABLE OF CONTENTS (cont'd)
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E-6-3-1
E-6-1-1
E-6-2-1
Page No.
E-6-2-1
E-6-2-2
E-6-2-3
E-6-2-4
E-6-2-11
E-6-2-17
E-6-2-23
E-6-4-1
E-6-4-3
E-6-4-4
E-6-4-4
E-6-5-1
E-6-6"'1
E-6-3-1
E-6-3-4
E-6-3-4
E-6-3-11
E-6-3-11
·E....6-j~TI
E-6-3-12
•••
•••
·..
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•••
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••
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•••
••
••
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...(*)
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GOG •••• • •e e e •0 • • •9 e 0 e e
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2.1 -Regional Geology (*)••••••••
2.2 -Quarternary Geology (*)• • • ••• • • •••
2.3 -Mineral Resources (0)• • • • • • ••• •••
2.4 -Seismic Geology (*)• ••••
2.5 -Watana Damsite (**)••••~•••••••••••
2.6 -Devil Canyon Damsite (0)••••••••••
2.7 -Reservoir Geology (*).•• • • • • • • •
EXHIBIT E -CHAPTER 6
GEOLOGICAL AND SOIL RESOURCES
3.1 -Reservoir-Induced Seismicity (RIS)(*)
3.2 -Seepage (*)• • • • • • • •••
3.3 -Reservoir Slope Fail.ures (**)• • • • • • •
3.4 -Permafrost Thaw (*)• • • • • • • • • •
3.5 -Seismically-Induced Failure(*)••••
3~6-"~"'ReservoTr~FreeDoarar-orWIne:CWaves (*'*)••
3.7 -Development of Borrow Sites and Quarries (**)
3 -IMPACTS (*)••
1 ...INTRODUCTION (**)
Title
2 -BASELINE DESCRIPTION
5 -REFERENCES
851014
4 -MITIGATION (**)..
6 -GLOSSARY
4.1 -Impacts and Hazards (0)• • • • •••E-6-4-1
4.2 -Reservoir-Induced Seismicity (0)E-6-4-1
4.3 -Seepage (**).• • • • • • • • • • • • •E-6-4-2
....-"4;4-Reservoir S-lopeFailures .(**);--;-;.;;~-;--.;--;-E-6-4=2
..------~-----..--·-.----4,,5~---Pe-rm:a-f-rost-Thaw~+**-)••-..-----;:-~
4.6 -Seismically-Induced Failure (*)•
4.7 -Geologic Hazards (*)••••••
4.8 -Borrow and Quarry Sites (*)• • • • • • • • •
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 7
.RECREATIONAL RESOURCES
Title Page No.
1 -INTRODUCTION (**)• •o ••00.o •• •Cl •0 o 0 E-7-1-1
1.1 -Purpose (**)• •
1.2 -Relationships to Other Reports (*)•••
1.3 -Study Approach ..and Methodology (**)••
1.4 -Project Description (**)•••••
E-7-1-1
E-7-1-1
E-7-1-1
E-7-1-3
2 -DESCRIPTION OF EXISTING AND FUTURE RECREATION
WITHOUT TUB SUSITNA PROJECT (**)••8 • • •·..••E-7-2-1
2.1 -Statewide and Regional Setting (**)
2.2 -Susitna River Basin (**)••••••...E-7-2-1
E-7-2-8
3 -PROJECT IMPACTS ON EXISTING -RECREATION (**)•
3.1 -Direct Impacts of Project Features (**)
3.2 -Project Recreational Demand Assessment
(Moved to Appendix E4.7)
•••o •E-7-3-1
E-7-3-1
E-7-3-12
4 -FACTORS INP'LUENCING TIm RECllEATION PLAN (**)• • ••0 E-7-4-1
4.1 -Characteristics of the Project Design and
Operation (***)• • • • • • • • • • • • • •
4.2 -Characteristics of the Study Area (***)•
4.3 -Recreation Use Patterns and Demand (***)••••
4.4 -Agency,·Landowner'and Applicant Plans and
Policies.(***)••••••••••••••
4.5 -Public Interest (***)•••••••••••
4.6 -Mitigation of Recreation Use Impacts (***)
E-7-4-1
E-7-4-2
E-7-4-2
E-7-4-3
E";7-4-12
E-7-4-13
5 -RECREATION PLAN (**)• • • • •8 •0 ••• • • •••0 E-7-5-1
5.1 -Recreation Plan Management Concept (***)
5.2 -Recreation Plan Guidelines (***)
5.3 -Recreational Opportunity Evaluation.
(Moved to Appendix E3.7.3)
5.4 -The Recreation Plan (**)••
E-7-5-1
E-7-5-2 '
E-7-5-4
E-7-5-4
6 -PLAN I:MPL.EMENTATIOH (**)
851014
e 0 0 •••0 ••0 • • • •0
xxi
E-7-6-1
SUMMARY TABLE OF CONTENTS (cont'd)
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Page No.
E-7-10-1
E-7-7-1
E-7-6-1
E-7-6-1
E-7-6-2
E-7-6-3
E-7-8-1
E-7-8-1
E-7-8-1
E-7-8-2
E-7-7-1
E-7-7-1
E-7-7-2
E-7-8....1
-E~7-9-1,.
••
. . ....
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G •Co •0 Cl
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xxii
RECREATION SITE INVENTORY AND OPPORTUNITY EVALUATION'
EXAMPLES OF TYPICAL RECREATION FACILITY DESIGN
STANDARDS FOR THE SUSITNA PROJECT
PROJECT RECREATIONAL DEMAND ASSESSMENT
DATA ON REGIONAL RECREATION FACILITIES
PHOTOGRAPHS OF SITES WITHIN THE PROJECT RECREATION
·'STUDY .AREA
EXHIBIT E -CHAPTER 7
RECREATIONAL RESOURCES
7.1 -Construction (**)••0 •••0
7.2 ~Operations and Maintenance (**)••••
7.3 -Monitoring (***)••••••••
6.1 -Phasing (**)••••0 ••0 ••
6.2 -Detailed Recreation Design (***)
6.3 -Operation and Maintenance (***)••
6.4 -Monitoring (**)•••••••••
8.1 -Agencies and Persons Consulted (**)•
8.2 -Agency Comments (**)•••••
8.3 -Native Corporation Comments (***)
8.4 -Consultation Meetings (***)•••
7 -COSTS FOR CONSTRUCTION AND OPERATION OF THE PROPOSED
RECREATION FACILITIES (**)•••e 0 0 • • • •0 •
E2.7
E1.7
Title
E5.7
8 -AGENCY COORDINATION (**)
E4.7
851014
APPENDICES
,9._...REFERENCES
10 -GLOSSARY.
"
SUMMARY TABLE OF CONTENTS (eont'd)
EXHIBIT E -CHAPTER 8
AESTHETIC RESOURCES
Title
1 -INTRODUCTION (**)•.....• •c e •0 • 0 C e ...... ....
Page No.
E-8-l-l
eo.•e 0 e • ••• •0 • • • •
1.1 -Purpose (*)••••
1.2 -Relationship to Other Analyses (*)
1.3 -Environmental Setting (**)o.eoe.
2 -PROCEDURE (*)....••••
3 -STUDY OBJECTIVES (*)
..."c e •c·••• •·...
E-8-l-l
E-8-1-l
E-8-l-1
E-8-2-1
E-8-3-1
4 -PROJECT FACILITIES (*)• • •Q.•0 &•0 • •0 0 •••E-8-4-1
4.1 -Watana Project Area (*).• • • • • • • •
4.2 -Devil Canyon Project Area (*)•
4.3 -Watana Stage III Project Area (***)•
4.4 -Denali Highway to Watana Dam Access Road (*)
4.5 -Watana Dam to Devil Canyon Dam Access Road (*)
4.6 -Transmission Lines (*)• • • • •
4.7 -Intertie ••••••••0 • 0 •••••••••
(This section deleted)
4.8 -Recreation Facilities and Features (*)
E-8-4-1
E-8-4-l
E-8-4-1
E-8-4-l
E-8-4-2
E-8-4-2
E-8-4-2
E-8-4-2
5.1 -Landscape Character Types (*)
5.2 -Notable Natural Features (**). .
. .. . .
5 -EXISTING LANDSCAPE (**)• •• •fIl •...
. .
e eo.• •
...E-8-5-l
E-8-5-1
E-8-5-l
6 -VIEWS (**)• • • ••• • • 0 • • • • • • • • • • • • •E-8-6-l
• • • • • • • 0
••••
6.1 -Viewers (***)
6.2 -Visibility (***)
7 -AESTHETIC EVALUATION RATINGS (**)
7.1 -Aesthetic Value Rating (*)
7.2 -Absorption Capability (*)•
7.3 -composite Ratings (**)
• •
·..·...· . .
..
..
.. .
·. .
·...
E-8-6-l
E-8-6-l
E-8-7-1
E-8-7-1
E-8-7-l
E-8-7-2
851014 xxiii
rI
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 8
AESTHETIC RESOURCES
1
)
]
lE-8-8-1
Page No.
E-8-8-1
E-8-8-2
E-8-8-3
E-8-8-4
E-8-8-5
E-8-8-6
·,..·... .
~Q 0 •e e • • •e •e 00 ••
8.1 -Mitigation Planning of Incompatible
Aesthetic Impacts (Now addressed in Section 9)
8.2 -Watana Stage I (***)••••
8.3 -Devil Canyon Stage II (***)•• • • • • •••
8.4 -Watana Stage III (***)• • • ••
8.5 -Access Routes (***)••
8.6 -Transmission Facilities (***)•
8 -AESTHETIC IMPACTS (**)
Title
10 -AESTHETIC IMPACT EVALUATION OF THE INTERTIE
_____(T!ttEJS~~t;:i.()~~~lec:::~~~)
9.1 -Mitigation Feasibility (**)•
9.2 -Mitigation Plan (***)•••
9.3 -Mitigation Costs (**)••••
9.4 -Mitigation Monitoring (***)•
e •0 II G
•e _ •e
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'iE-8-10-1
E-8-9-1
E-8-11-1
E-8-9-1
E-8-9-2
E-8-9-11
·E-8-9-12
• •
o •II •
•••
...
•0
.....
e _ • •o •
11 -AGENCY COORDINATION (**)•
9 -MITIGATION (*'*)•e •••••
SITE PHOTOS WITH SIMULATIONS OF PROJECT FACILITIES
E-8-12-1
li:-8-11-1
E-8-11-1
00 ..
· . ......•0
....
D I)0 ••Cl ..
e •• • • •e
...
••
.....
• • •Cl
EXCEPTIONAL NATURAL FEATURES
11.1 -Agencies and Persons Consul ted (**).
11.2 -Agency Comments (**)
E2.8
E1.8
APPENDICES
12 -REFERENCES ..
E3.8 PHOTOS OF PROPOSED PROJECT FACILITIES SITES
E4.8 EXAMPLES OF EXISTING AESTHETIC IMPACTS
851014 xxiv
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 8
AESTHETIC RESOURCES
Title
APPENDICES (cont'd)
Page No.
E5.8
E6.8
E7.8
B8.8
E9.8
851014
EXAMPLES OF RESERVOIR EDGE CONDITIONS SIMILAR TO THOSE
ANTICIPATED AT WATANA AND DEVIL CANYON DAMS .
PROJECT FEATURES IMPACTS AND CHARTS
GENERAL AESTHETIC MITIGATION MEASURES APPLICABLE TO THE
PROPOSED PROJECT
LANDSCAPE CHARACTER TYPES OF THE PROJECT AREA
AESTHETIC VALUE AND ABSORPTION CAPABILITY RATINGS
xxv
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 9
LAND USE
Title
2 -HISTORICAL AND PRESENT LAND USE (***)
r
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Page No.
E-9-1-1
E--9-2-1
E-9-2-1
E-9-2-1
o 8oee
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COO e 0
e e 0
•00«1
2.1-Historical Land'Use (***)
2.2 -Present Land Use (***)
1 -INTRODUCTION (***)8 • • •8 ..• 0 e 0
3 -LAND MANAGEMENT PLANNING IN THE PROJECT
AREA (**'*:)• • • • • • •G eo.0 •o·•CD •0 e 0 e'•E-9-3-1
4 -IMPACTS ON LAND USE WITH AND WITHOUT THE
PROJECT (***)•••••••••••e • • e 8
5 -MITIGATION (***)•
• • •e
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E-9-6-1
E-9-4-1
E-9-5-1
8 0
e 0 0
..0 0
e e "It e
e lit • •
..0
e 0
8 •••• •
•8
•eo.•0 •••e •6-REFERENCES
851014 xxvi
]
1
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1
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 10
ALTERNATIVE LOCATIONS,DESIGNS,AND ENERGY SOURCES
Title
1 -ALTERNATIVE HYDROELECTRIC SITES (*)e •e e 0 C 0 o • •
Page No.
E-10-1-1
1.1 Non-Susitna Hydroelectric Alternatives (*)E~10-1-1
1.2 -Assessment of Selected Alternative
Hydroelectric Sites (***)• • • • •E-10-1-2
1.3 -Middle Susitna Basin Hydroelectric
Alternatives (0)••••••••••••••E-10-1-17
1.4 -Overall Comparison of Non-Susitna
Hydroelectric Alternatives t~the
Proposed Susitna Project (***)•••••••••E-10-1-32
e·• •0 0 e •e •e 02 -ALTERNATIVE FACILITY DESIGNS (*)
2.1 -Watana Facility Design Alternatives (*)•
2.2 -Devil Canyon Facility Design Alternatives
2.3 -Access Alternatives (0)•••••••
2.4 -Transmission Alternatives (0)
2.5 -Borrow Site Alternatives (**).
. .
(0)• •
E-10-2-1
E-10-2-1
E-10-2-3
E-10-2-4
E-10-2-24
E-10-2-53
3 -OPERATIONAL FLOW REGIME SELECTION (***)••••••••E-10-3-1
· ..3.1
3.2
3.3
3.4
3.5
3.6
3.7
-Project Reservoir Characteristics (***)•
-Reservoir Operation Modeling (***)
-Development of Alternative Environmental
Flow Cases (***)••••••••••••••••
-Detailed Discussion of Flow Cases (***)• • • • •
-Comparison of Alternative Flow Regimes (***)
-Other Constraints on Project Operation (***)
Power and Energy Production (***)• • • • • •
E-10-3-1
E-10-3-2
E-10-3-6
.E-10-3-17
E-10-3-38
E-1O-3-43
E-10-3-53
4 -ALTERNATIVE ELECTRICAL ENERGY SOURCES (***)•••.0.E-10-4-1
4.1 -Coal-Fired Generation Alternatives (***)
4.2 -Thermal Alternatives Other Than Coal (***)
4.3 -Tidal Power Alternatives (***)••.•
4.4 -Nuclear Steam Electric Generation (***)
4.5 -Biomass Power Alternatives (***)
4.6 -Geothermal Power Alternatives (***)••
· . .
E-lO-4-1
E-lO-4-27
E-lO ....4-39
E-1O-4-41
E-lO-4-42
E-lO-4-42
851014 xxvii
SUHMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 10
ALTERNATIVE LOCATIONS»DESIGNS J AND ENERGY SOURCES
1:
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Page No.
E-IO-4-43
E-1O-4-44
E-IO-4-44
E-IO-5-1
E-IO-7-l
E-IO-6-1
••
. ..
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xxviii
• • 0 GOO 8 ••G e $• •e e •eGO e •
••• • •eo.•e 9 e 0 0 e e •e e _•0 e
4.7 -Wind Conversion Alternatives (***)••
4.8 -Solar Energy Alternatives (***)• • •
4.9 -Conservation Alternatives (***)~•
Title
7 -GLOSSARY
5 -ENVIRONMENTAL CONSEQUENCES OF LICENSE DENIAL (***)
6 -REFERENCES
851014
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT E -CHAPTER 11
AGENCY CONSULTATION
Title Page No.
.0.• ••0 • •
1 -ACTIVITIES PRIOR TO FILING THE INITIAL
APPLICATION (1980-February 1983)(***)
2 -ADDInONAL FORMAL AGENCY AND PUBLIC
CONSULTATION (***).. .. ........ ....•............•O'• •
E-ll-1-1
E-1l-2-1
2.1 -Technical Workshops (***).
2.2 -Ongoing Consultation (***)• • .
2.3 -Further Comments and Consultation (***)•••
E-1l-2-1
E-1l-2-1
E-1l-2-2
851014 xxix
SUMMARY TABLE OF CONTENTS (cont-d)
5.1 -River Flows (**)• • • • • • • • •••F-5-l
5.2 -Design Flows (**)• • • •F-5-1
5.3 -Reservoir Levels (**)• • • • • • • • • •••F-5-l
-··-····-·······-5-.4-Reservoir0perating'-Rule (**).• • • •.~.•-F-5-2
.--~-·-·_-·_--_··----···_-·--5·•.s----·Rese-r.voi-r-Data--(-**-)......,.-..•--.--.---.-.-.--.•'-r-..----·.--.--r ..-.-·..-·-F--5-~-··-··..-..--.,.---
5.6 -Wind Effect (**)• • •• • • •F-5-3
5.7 -Criteria (***)•••••••••••F-5-3
EXHIBIT F
SUPPORTING DESIGN REPORT (PRELIMINARY)
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F-4-10
F-2-1
F-4-1
F-5-1
F-3-.l
F-6-1
F-l-l
F-3-1
F-3-1
F-3-6
F-3-9'
F-2-1
F-2-1
F-2-1
F-2-1
F-2-1
F-2-2
F ...6-1
F-6-2
Page No.
••
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•••
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(0)
• 0 • • 0 ••• 0 •• 0 e ••
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Standards (0)
· .
.0.
•••
3.1 -Governing Codes and
3.2 -Design Loads (**)•
3.3 -Stability (*)• • •
3.4 -Material Properties
2.1 -Topographical Data (0)•••••••• • • •
2.2 -Hydrological Data (**)•••••••••••
2.3 -Meteorological Data (*)••••••••••
2.4 -Reservoir Data (0)••.•• • • • • • • • •
2.5 -Tailwater Elevations (0)••••••••
2.6 -Design Floods (**)•••••••••••
4.1 ;;.;Watans.(**).~.• •
4.2 -Devil Canyon (**)
6.1 -Design Codes and Standards (*)•••..••
6.2 -General Criteria (*)•••••••
3 -CIVIL DESIGN DATA ('~)
Title
4 -GEOTECHNICAL DESIGN DATA (**)'.
5 -HYDRAULIC DESIGN DATA (**)
2 -PROJECT DESIGN DATA (**)
1 -PROJECT DATA (***).
6 -EQUIPMENT DESIGN CODES AND STANDARDS (**)•
851014 xxx
.J
SUMMARY TABLE OF CONTENTS (cont'd)
EXHIBIT F
SUPPORTING DESIGN REPORT (PRELIMINARY)
Title
6.3 -Diversion Structures and Emergency Release
Facilities (*)••••• •
6.4 -Spillway (**)• • • • • • • • • •
6.5 -Outlet Facilities (*)•
6.6 -Power Intake (*)'.•
6.7 -Powerhouse (**)•••••••••••
6.8 -Tailrace Tunnels (**)• • • • •. ..
Page No.
F-6-4
F-6-6
F~6~6
F-6-8
F-6-9
F-6-12
7 -REFERENCES
APPENDICES
• •0 e e • • • • • •e •••0 •e • • • •F-7-1
F1
F2
F3
851014
THIS APPENDIX DELETED
WATANA AND DEVIL CANYON EMBANKMENT STABILITY ANALYSES
SUMMARY ANDPMF AND SPILLWAY DESIGN FLOOD ANALYSES
xxxi
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CHAPTER 3
FISH,WILDLIFE
AND BOT ANIC··AL RESOURCES
SECTIONS 1 AND 2
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1 -INTRODUCTION
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SUSITNA HYDROELECTROC PROJECT
LICENSE APPLICATION
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,AND BOTANICAL RESOURCES
TABLE OF CONTENTS
Title
1 -INTRODUCTION (0)
1.1 -Baseline Descriptions (0)
1.2 -Impact Assessments (*)
1.3 -Mitigation Plans (*).
Page no.
E-3-1-1
E-3-1-1
E-3-1-1
E-3-1-3
851022 i
Number
E.3.l.l
851022
EXHIBIT E -CHAPTER 3
FISH AND WILDLIFE MITIGATION POLICY
LIST OF TABLES
Title
MITIGATION OPTIONS ANALYSIS STRUCTURE RECOMMENDED BY
SUSITNA HYDROELECTRIC PROJECT,ALASKA DEPARTMENT OF
FISH AND GAME AND THE U.S.FISH AND WILDLIFE SERVICE
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E.3.!.2
851022
EXHIBIT E -CHAPTER 3
FISH AND WILDLIFE MITIGATION POLICY
LIST OF FIGURES
Title
OPTION ANALYSIS
MITIGATION PLAN DEVELOPMENT AND IMPLEMENTATION
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EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,AND BOTANICAL RESOURCES
1 -INTRODUCTION (0)
This report discusses the fish,vegetation,and wildlife resources of
the area that will be affected by the proposed Susitna Hydroelectric
Project.Each of the major subsections (2 -Fish,3 -Botanical
Resources,and 4 -Wildlife)provides a baseline description of species
and populations of the project area;an assessment of potential project
impacts on this biota (assuming no mitigation);and a mitigation plan
that explains how preliminary engineering design and construction plan-
ning have incorporated measures to avoid,minimize,or rectify poten-
tially adverse effects of the project on the biological environment.
In appropriate cases,resource management options to reduce or
compensate for adverse impacts that cannot otherwise be mitigated are
discussed.
1.1 -Baseline Descriptions (0)
These sections describe the distributions and characteristics of bio-
logical populations and communities within the project area.The
discussions are based on a thorough review of the scientific literature
and emphasize documented studies conducted in preparation for the
Susitna Hydroelectric Project by the Alaska Department of Fish"and Game
.and professional consultants.They provide the most current available
information through March 1985 on.fish,vegetation,and wildlife of the
project area.
Discussions of animals focus on vertebrate species:resident and anad-
romous fish,big game·,furbearers,birds,and non-game (small)mammals.
The plant descriptions deal .with species aggregations that occur in
recognizable patterns,such as vegetation communities and successional
stages.
The baseline descriptions emphasize functional relationships among
habitat components and animal communities.Factors that regulate
species distribution and abundance receive particular attention,
because knowledge of these regulating mechanisms can suggest where
populations are most sensitive to potential disturbance.For example,
water temperature and stream regimes are discussed as regulators of
fish populations,and the role of plant communities in regulating wild-
life populations is examined.
1.2 -Impact Assessments (*)
It is expected that the distribution and abundance of fish,plant,and
wildlife species in and around the area of the Susitna Hydroelectric
851022 E~3-1-1
Project will change as a result of project construction and operation •
.The impact assessments presented in this report are based,in part,on
the project description presented in Exhibit A,project operations
described in Exhibit B,the proposed construction schedule shown in
Exhibit C,the impacts on water use and quality presented in Exhibit E
Chapter 2 and an analysis of similar activities associated with large
construction and hydroelectric projects in similar habitats.In
addition,the Recreation Plan presented in Exhibit E,Chapter 7,has
been reviewed as a proposed project action to determine its potential
impacts on fish,vegetation,and wildlife.The impact assessments link
predicted physical changes with habitat utiliza.tion to provide a
qualitative statement of impacts likely to result from the Susitna
Hydroelectric Project.Quantitative assessments are presented where
justified by current knowledge and research techniques.Changes
potentially resulting from the project are discussed.with respect to
specific project features and activities,assuming standard engineering
design and construction practice without the incorporation of
mitigation measures.
Although some project impacts,if not mitigated,will be adverse,other
impacts will be innocuous and some will enhance fish or wildlife
productivity.Therefore,potentially beneficial itnpactsare given
balanced treatment with.those to be mitigated,.Each potential effect,
together with the action responsible for it,is called an impact
issue.
The identification and prioritization of impact issues have followed
the procedures established by the Susitna Hydroelectric Project Fish
and Wildlife Mitigation Policy (Appendix E1.3)•This policy was
..pr-epared·-by-theAppiicant -through extensiveconsul tation wi ttl-"
representatives of the following resource agencies:
o Alaska Department of Fish and Game (ADF&G);
o Alaska Department of Natural·Resources (ADNR);
o Alaska Department of Environmental Conservation (ADEC);
o National Marine Fisheries Service (NMFS);
o U.S.Bureau of Land Management (USBLM);
."'0'"u.S;Environmental··Protection··Agency-(USEPA);··an-d ....----...-.....
·-·-·-····-o-U-.-S·.--F-i-sh~a·nd-W·i-ld-l-i-f~Ser·vi·ce-(-USF·WS-}...-----------···-·-··-··-······--·
Criteria for assessing.the relative importance of biological impact
issues have been provided by;(1)mitigation policies of the Alaska
Department of Fish and Game (ADF&G 1982a),theU.S.Fish and Wildlife
Service (USFWS 1981c),and the Applicant (Appendix El.3);(2)letters
and testimony by local ,state,and federaL agencies;and (3}discus-
sions of impact issues in workshops and numerous other technical
mee t i l1gs i llvolvillg Susi tllapr6ject.pe rs6nllel,.alld-.resource ..agency:-
representatives.
All three mitigation policies from APA,USFWS,and ADF&G imply that
project impacts on the habitats of certain sensitive fish and wildlife
,)
1
1
1
851022 E-3-1-2
I
I
species will be of greater concern than changes in distribution and
abundance of less sensitive species.Sensitivity can be related to
high human use value as well as susceptibility to change because of
project impacts.The policies and comments also indicate that,for the
Susitna Project area,vegetation is considered more important as a
component of wildlife habitat than as a botanical resource in itself.
Statewide policies and management approaches of resource agancies
suggest that concern for fish and wildlife species with commercial,
subsistence,and other consumptive uses is greater than for species
without such value.These species are often large,sometimes numerous,
and utilize a wide range of habitats,as well as having high human use
value.Such characteristics often result in these species being
selected for careful evaluation when their habitats are subjected to
alternative uses.By avoiding or minimizing alterations to habitats
utilized by these evaluation species the impacts to other less
sensitive species that utiliie similar habitats can also be avoided or
reduced.
The mitigation policies all agree that resource vulnerability is an
important criterion for impact prioritization.Resources judged most
vulnerable to potential project impacts have therefore been given
highest priority in impact assessment and mitigation planning.Simi-
larly,impact issues have been considered with regard to probability of
occurrence.Where there is a high degree of confidence that an impact
will actually occur,it has been ranked above impacts that are
predicted to be less likely to occur.Also,the mitigation policies
and agency comments indicate that impacts on animal productivity and
population size through changes in habitat availability are of high
concern.Behavioral responses that have the potential for producing
population-level effects are also important.Adverse impacts that are
longer lasting or irreversible have priority over short-term impacts.
1.3 -Mitigation Plans (*)
Mitigation plans have been developed for identified impact issues in
accordance with the sequence of steps defined by 40 CFR 1508.20,
pursuant to the National Environmental Policy Act (42 USC 4321 et
seq.).
The mitigation planning sequence includes,in priority order of imple-
mentation,the following steps:
o Avoiding the impact through project design and operation,or by
not taking a certain action;
o Minimizing the impact by reducing the degree or magnitude of the
action,or by changing its location;
o Rectifying the impact by repairing,rehabilitating,or restoring
the affected portion of the environment;
851022 E-3-1-3
o Reducing or eliminating the impact over time by preservation,
monitoring,and maintenance operations during the life-of the
action;and
o Compensating for the impact by providing replacement or
substitute resources that would not otherwise be available.
This sequential strategy for mitigation option analysis and implementa-
tion is shared by all three mitigation policies applied to the project
(the Applicant -see Appendix E1.3,ADF&G 1982a,USFWS 1981c).The
relationships of steps within the sequence are shown in Figure
E.3.1.1 and further compared in Table E.3.1.1.
The process by which mitigation will be implemented and continually
refined throughout the life of the project is shown schematically in
Figure E.3.1.2.The process involves the following steps:
o Impact issue evaluation:
Identification of the nature and extent of impacts:
Populations
Subpopulations
Habitat types
Geographical areas
Prioritization of impacts:
Ecological value of affected resource
Consumptive value of affected resource
_____Re_s_o_ur_c_e_Y'J,11nerabilLty~~~~_~c
Confidence of impact prediction
Long-term vs.short-term impacts
o Option analysis procedure:
Identification of practicable mitigation options:
Type of mitigation option
Sequence of implementation
----------------
----------------Eva-l:uati-on-of----miti-gati-on-options-:------..-----------------------------------------------._.
Effectiveness of option
Conflicts with project objectives
Residual impacts
Documentation of option analysis:
Impact issues
Mitigation options
Conflicts (if-any)with-project objectives ._.c __•
1
851022 E-3-1-4
J
o Negotiation of acceptable plan
o Mitigation plan implementation:
Engineering design and construction planning:
Participate in design development
Participate in preconstruction field surveys and site
evaluations
Review designs,schedules,permit applications
construction and operation monitoring:
Review work accomplished
Evaluate degree of impact
Evaluate effectiveness of mitigation
Identify modifications to the mitigation plan
Submit regularly scheduled reports
Mitigation plan modifications:
Propose modifications
Submit modifications for review
Implement and monitor approved modifications
Data from the baseline,impact,and monitoring studies will be used
throughout the life of the project to plan and continually refine the
mitigation process in a flexible,adaptive fashion.
Mitigation measures proposed for operation of the Susitna Hydroelectric
Project may be classified within two broad categories:
o Modifications to design,construction,or operation of the
project;and
o Mitigation for impacts that cannot be mitigated through
modifications to design or operation of the project.
The first type of mitigation measure is project-specific and emphasizes
the avoidance,minimization,rectification,or reduction of adverse
impacts,as prioritized by the Fish and Wildlife Mitigation Policy
established by the Applicant (Appendix El.3)and coordinating agencies
(ADF&G 1982a,USFWS 1981c).As shown in Figure E.3.1.1,these measures
must first be implemented to keep adverse impacts to the minimum
consistent with project requirements.They involve adjusting or adding
project features during design and planning so that mitigation becomes
a built-in component of project actions.
Mitigation of construction impacts will be achieved primarily by
incorporating environmental criteria into preconstruction planning and
design,and by good construction practices.Incorporation of
environmental criteria into design activities and construction of the
Susitna dams and related facilities such as transmission lines and
access roads will avoid,minimize or rectify impacts to fish and
851022 E-3-1-5
The Applicant has prepared five Best Management Practices (BMP)Manuals
(APA 1985a,b,c,d,e)to be.used in the design,construction and
maintenance of the Applicant's projects.These manuals are entitled:
1.Fuel and Hazardous Materials
Oi!Spill Contingency Planning
3.Water Supply
4.Liquid and Solid Waste Management
5.Erosion and Sedimentation Control
A report entitled "Drainage Structure and Waterway Design Guidelines"
was also prepared (Harza-Ebasco 1985b)to establish the proper
procedure for the design of drainage structures and waterways.
These manuals are the result of a coordinated effort involving federal,
state,and local government agencies,and special interest groups.The
manuals will be provided to the design engineer,who will utilize them
in the preparation of both design and construction documents.The
Applicant intends that applicable guidelines contained in these manuals
will be incorporated where appropriate into the contractual documents
for the Project.
When impacts cannot be fully avoided or rectified,reduction or compen-
sation measures are justified.This type of mitigation can involve
management oJ:.the -r~~QJlrceit.~eU,-.-r~t:be!".t:bC!ll <iclJ1,!§tmE!.ltt:~t:c>tbe
project,and will require concurrence of resource management boards or
agencies with jurisdiction over lands or resources within and around
the project area.
Mitigation planning for operation of the Susitna Hydroelectric Project
has emphasized both approaches.The prioritized sequence of options
from avoidance through compensation has been applied to each impact
issue.If full mitigation can be achieved at a high priority option,
lower··opti-onsmayffot--oe-cons-idet'e-d-.--To:-thet'-estitti-ngtniti-ga:t-ion-
---.-.----~-------~-~pi-ans,_me-a·suresc-to-avoid,-minimi-ze-,-or--rec-ti-fy-potenti-a-l~impac-t-s--are-------.-.-
treated in greatest detail.
Monitoring and maintenance of mitigation features to reduce impacts
over time are recognized as an integral part of the mitigation process.
To assure that the mitigation plans achieve their intended goals,
monitoring plans for aquatic and terrestrial resources have been
develped and are described in this license application.
)
, 1
851022 E-3-l-6
-c
TABLES
L __
TABLE E.3.1.1:MITIGATION OPTIONS ANALYSIS STRUCTURE RECOMMENDED BY SUSITNA HYDROELECTRIC PROJECT,
ALASKA DEPARTMENT OF FISH AND GAME (~&G)AND THE U.S.FISH AND WILDLIFE SERVICE
(USFWS).DESIRABILITY OF OPTIONS DECREASES FROM TOP TO BOTTOM.EXPLANATIONS OR
EXAMPLES OF EACH OPTION AS DESCRIBED BY AGENCIES ARE SHOWN
OPTION
AVOIDANCE
MINIMIZATION
ALASKA DEPARTMENT OF FISH AND GAME
Avoid Impact by Not Taking a Certain Action
-Keep as much eXisting natural habitat as possible.
-Maintain fish and game populations and critical
habitats.
Minimize Impacts by Limiting Magnitude of Action
-Maintain habitat diversity and the capacity of each
system to restore itself naturally.
DEFINITION
U.S.FISH &WILDLIFE SERVICE
Modify Project Design to Avoid Impact
-No-project alternative is one mode.
-Design modifications in action type,magnitude,timing
and locations are options.
Modify Project Design to Minimize Impacts
-Design modifications in action type,magnitude,timing
and location are options.
RECTIF IcA TION
RESTRICTION
COMPENSATION
Rectify Impacts by Rehabilitating Environment
-Repair,rehabilitate or restore abused aquatic or
terrestrial systems.
-Restore the same functions or structure of habitats.
Reduce (or Eliminate)Impact Over Time by Maintenance
-Operate and maintain mitigation measures to reduce
impacts over time.
Compensate for Impact by Substitute Resources
-Create or restore fish,wildlife and habitat values,
and resource use opportunities that were unavoidably
lost.
-Compensation by providing substitute resources or
environments is least desirable;the preferred mode
is onsite mitigation.
Restore Damaged Environments
-Reclaim disturbed sites by seeding,etc.
-Restock lost fish and wildlife.
Maintain Mitigation Effort to Reduce Impact
-Monitor and maintain mitigation measures.
-Train mitigation personnel.
Restore Lost Resources by Management or Replacement
-Intensify production through management.
-Initiate hatcheries;restocking programs.
-Lease or ·buy new lands for enhanced management.
1
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FIGURES
SOME MINIMIZATION
PA;~AV~,ANCE ...;...1-----...,_1:1\,1111-----1...-;;0.TOTAL AVOIDANCE
~,.,5'\.-..
NO AVOIDANCE '!:{.-~1_,
If ({.(5-'
t·\JL..--------......-t:·IIGlll1:t----.......
\'
".--'r
/1 ,
.:~..~:c;.
(
I
NO MINIMIZATION
t.
PARTIAL RECTIFICATION ......----IEI1~;~I::J-___'....
g ,Ir."r::.:
NO RECTIFICATIO'N-
TOTAL RECTIFICATION
c
(-,(~r.
~/,--(_.~_.\__~_.__1_,·--!IIIoffIlJIIIIII------l...
J~'--.::'."'l,.~-C I
[,r~:C'NO REDUCTION
,-
\
SOME REDUCTION
(.
''---
PARTIAL COMPENSATION("'11-..-..-[-_:--11:1)11111.....---......··TOTAL COMPENSATION
.~'t
~,-'
NO COMPENSATION
! .
/",
'""C·r~-_r---,
~"~-
{
j
/./".
---._-,."---",
c
{'
/'
"
OPTION ANALYSIS
c-
FIGURE E.3.1.1
'----------~-----------------------_.....,-
.,'-..;.
MITIGATION PLAN DEVELOPMENT AND IMPLEMENTATION
.~--."-
--------1-------------
~!!.-:....I
,.."'-~.--,-'-
IDENTIFICATION OF
IMPACTS AND GOALS OF PLAN
STEP 1
it
OPTION ANALYSIS
STEP 2
.....
NEGOTIATION OF'ACCEPT ABLE PLAN
STEP 3
".-
IMPLEMENT ATION OF PLAN
:"":'"-.STEP 4
J,
MONITORING OF PLAN
STEP 5
~-,,=-"...
PLAN MO·DIFICATIONS
STEP 6
.;'.~...".~,---
COMPLETION OF MITIGATION
...STEP 7,..
.-.._.-----_..
-/.~II
'-
---_._._._...__.__._----·--..n-~..-..-~-·----..-·--·-··--·-
TERMINATION OF MONITORING
STEP 8·
..
".....'.
-;1
:]
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:~
.!
'~
!
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FIGURE E 3,1.2
"I __~e-.11it116 HARZA-EBASCO
SUSITNA JOINT VENTURE
I
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2 -FISH RESOURCES O.F THE
SUSITNA .RIVER DRAINAGE
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTABICAL RESOURCES
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]
E-3-2-77
E-3-2 ....76
E-3-2-28
E-3-2-33
E-3-2-35
E-3-2-35
E-3-2-36
E-3-2-36
E-3-2-36
E-3-2-38
E-3-2-40
E-3-2-43
E-3-2-43
E-3-2-44
E-3-2-45
E-3-2-45
E-3-2-46
E-3-2-47
E-3-2-48
E-3-2-49
E-3-2-52
Page No.
ii
TABLE OF CONTENTS (co nt I d)
851021
Title
(iv)Chum Salmon (***)
(v)Pink Salmon (**)
(b)Other Anadromous Species (0)•
(i)Bering Cisco (0)
(ii)Eulachon (0)
(c)Resident Species (***)•
(i)Dolly Varden Char (***)
(ii)Rainbow Trout (***)• • • • •
(ii~)Arctic Grayling (*)••
(iv)Lake Trout (***)
.(v)Burbot (**)••••••
(vi)Round Whitefish (**)
(vii)Htunpback Wh itefish (**).
(viii.)I..()ngTJ,()13 es.tlck.~r J**)••
(ix)Threespine Stickleback (**)•
(x)Cottids (**)
(xi)Lamprey (0)• • • • • • • • •
2.2.2 -Habitat Utilization (***)••••••••
(a)Oshetna River to Devil Canyon (**)
(i)Mainstem Habitat Near the
Conflu~nce of MajorTributaries(***-j '.• •E-3-2-52
(ii)Tributaries (***)• • •E-3-2-53
(iii)Lakes and Ponds (***)E-3-2-54
(b),Devil Canyon to Talkeetna (**)E-3-2-55
(i)Mainstem Habitat (**).• •E-3-2-55
(ii)Side Channel Habitat (**)E-3-2-58
(iii)Tributary Mouth Habitat (**).E-3-2-60
(iv)Side Slough Habita t (**)E-3-2-62
···(v}··Upl-andSloughs (-**}-~•.•.~..•E-3-2:"65
~-----._-...-'-'---~-----.-----~~--·--·-..-----:----(-v-i-)--'I'-r-ibu·t;-a·rc-y---:-Ha·bi-t;-a·t--s-·(-**-)--.-.-.---E-3-2-66-
(c)Cook Inlet to Talkeetna (**)• • • •E-3-2-68
(i)Mainstem Habitat (**). •••E-3-2-69
(ii)Side Channel Complexes (**)•E-3-2-72
(iii)Tributary Mouth Habitat (**).E-3-2-73
(iv)Tributary Habitat (***)••E-3-2-74
2.2.3 -Habitat.Response~".tQ..,FlowChanges (*~~)E-3-2-74
(a)Surface Area Response to Flow
-Chatiges{***}.•-...••• • •.'
(b)Development of Representative
Groups of Habitat Sites (***)
EXHIBIT E -CHAPTER.3
FISH,WILDLIFE,.&BOTABICAL RESOURCES
-TABLE OF CORTERTS (cont'd)
Title
(c)Principal Habitat/Species
Combinat ions (***)• • ••.
(d)Quantification of Habitat Response
to Flow Changes (***). • . . .••
(i)Development of Suitability
Criteria (***)•.•••••
(ii)Determination of the Range
of Habitat Conditions
Available (***). • • .
(iii)Habitat Response Curves (***)
(e)Habitat Response Curves for
Non-Modelled Sites (***)•••••.
(f)Habitat Response to Natural
F low Regime (***)• • • • • • • • •
(i)Chinook Salmon Juvenile
Rearing Habitats (***)
(ii)Chum Salmon Spawning and
Incubation Habitats (*)
(g)Natural Ice Processes Effects
on Fish Populations and Their
Habitats (***). . . • • •.'.
(i)Effects of Natural Ice Proc-
esses on Resident Fish (***).
(ii)Effects of Natural Ice
Processes on Salmon
Juveniles (***)•••.
(iii)Effects of Natural Ice
Processes on Incubation
of Embryos (***)
2.2.4 -Streams of Access Road Corridor (**)
(a)Stream Crossings (**)
(b)Streams Adjacent to Access
Corridors (**). • . • . .
2.2.5 -Streams of the Transmission
Corridors (**)•.••.•
2.3 -Anticipated Impacts To Aquatic Habitat (**)
Page No.
E-3-2-79
E-3-2-81
E-3-2-81
E-3-2-82
E-3-2-83
E-3-2-85
E-3-2-88
E-3-2-89
E-3-2-91
E-3-2-97
E-3-2-99
E-3-2-99
E-3-2-100
E-3-2-103
E-3-2-103
E-3-2-104
E-3-2-104
E-3-2-105
J
851021
2.3.1 -Anticipated Impacts to Aquatic Habitat
Associated with Stage I Watana Dam (***).E-3-2-107
(a)Construction of Stage I Watana Dam
and Related Facilities (***). • • •E-3-2-107
l.U.
Title
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
TABLE OF OONTERTS (cont'd)
'.
(i)Stage I Watana Dam (***)
(iO Construction and Operation of
Stage I Watana Camp,Village
and Airstrips (*)
(b)Filling Stage I Watana
Reservoi r (***)• • • • •
(i)Watana Reservoir
Inundation (***)••••••
(ii)Watana Dam to Talkeetna (*)•
(iii)Talkeetna to Cook Inlet (*)•
(iv)Estuary at Cook Inlet (***)•
(c)Operation of Stage I-Watana Dam (**)
(i}Effec tso f S ta gel Watana
Reservoir Operation (**)
(ii)Watana Dam to Talkeetna (***)
(iii)Talkeenta to Cook Inlet (***)
(iv)Cook Inlet Estuary (***)
(d)Summary of Impacts Associated
with Watana Dam (**)••••••
~(-i)construction'Impact~s~(**1 .
(ii)Filling Impacts (**)
(iii)Operation Impacts (**)
2.3.2 -AntiCipated Impacts to Aquatic Habitat
Associated with Stage II Watana/Devi 1
Canyon Dam (***)••••••••••••
(a)Construction of Devil Canyon
Dam (Stage II)and Related
~~~J!~c::JHt!,~~~L~J~H!'__!.'.'!'!.•..!......•.....!.
(i)Devil Canyon Dam~~~~:"-::"~'---'(Stage II)('-"*--)----
(ii)Construction and Operation
of Devil Canyon Camp
and Village(*).• • •
(b)Filling Devil Canyon Reservoir (*)•
(i)Effects in Impoundment
Area (*)..•...•.....~'~.•••
O.i 5 Devil CatiY01:tr~to'Talkeenta
R.each (***r ~.~... .
(iii)Talkeetna to Cook Inlet (***)
(iv)Estuary at Cook Inlet (***)•
iv
Page No.
E-3-2-l07 ]
E-3-2-114
]
E-3-2-117
E-3-2-119
,JE-3-2-l20
E-3-2-l32
E-3-2-l37 ]E-3-2-l37
E-3-2-137
1E-3-2-l43
E-3-2:-l71
E-3-2-l76
'j
E-3-2-l76
E-3-2-l76
E-3-2-l77 jE-3-2-l78
E-3-2-l80 )
....E.::,J:-2:-J~1Q
.1
E-3-2-l80
j
E-3-2-183
E-3-2-l85
j
E"'3"'2"'185
E;:"'j:"'2-186 jE-3-2-l88
E-3-2-189
j
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Title
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
TABLE OF CONTENTS (cont'd)
(c)Effects of Operation of Stage II
Watana/Devil Canyon Dam (**)
(i)Effect of Operating Devil
Canyon Reservoir (**)
(ii)Devil Canyon to
Talkeetna (**)•••.
(iii)Talkeetna to Cook Inlet (***)
(iv)Cook Inlet Estuary (***)
(d)Summary of Impacts Associated with
Devil Canyon Stage II Dam (**)•••
(i)Construction Impacts (***)
(ii)Reservoir Filling (**)
(iii)Operation Impacts (**)••.
2.3.3 -Anticipated Impacts on Aquatic Habitat
Associated With Stage III Watana/Devi1
Canyon Dams (***).••.....
(a)Construction Impacts Stage III (***)
(i)Watana Stage III Con-
struction Effects (***)
(ii)Operation of Stage III
Watana Camp,Village and
Airfield (**)• • • • • .
(b)Anticipated Impacts on Aquatic
Habitats of Filling Stage III
Watana/Devi1 Canyon (***)
(i)Watana Reservoir
Filling (***)•••
(ii)Devil Canyon to
Tal kee tna (***)
(iii)Talkeetna to Cook Inlet (***)
(iv)Es tuary at Cook Inle t (***)•
(c)Anticipated Impacts on Aquatic
Habitats of Operation of Stage III
Watana/Devil Canyon Dams (***). • •
(i)Impacts of Stage III Watana
Reservoir Operation (***)
(ii)Devil Canyon to
Talkeetna (***)• •
(iii)Talkeetna to Cook Inlet (***)
(iv)Estuary at Cook Inlet (***)•
v
Page No.
E-3-2-189
E-3-2-190
E-3-2-192
E-3-2-207
E-3-2-209
E-3-2-209
E-3-2-209
E-3-2-209
E-3-2-210
E-3-2-210
E-3-2-211
E-3-2-211
E-3-2-213
E-3-2-213
E-3-2-214
E-3-2-214
E-3-2-216
E-3~2-218
E-3-2-218
E-3-2-218
E-3-2-221
E-3-2-235
E-3-2-237
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTARICAL RESOURCES
TABLE OF CONTENTS (cont'd)
Title
(d)Summary of Impacts Associated with
Stage III Watana Dam (***)••••.
(i)construction Impacts (***)
(ii)Filling (***)••••••
(iii)Operation (***)•...•
2.3.4 -Impacts Associated with Access Roads,
Site Roads,and Railroads (**)
(a)Construction (**)•••••••
(i)Construction of Watana.Access
Road and Auxiliary Roads (**)
(ii)Construction of Devil
Canyon Access Road and
Auxiliary Roads (**)••.•
(b).Use,and Maintenance of Roads (**)
(i)Use and Maintenance of Watana
Access Road and Auxiliary
Roads (**)••.•.••.•
(ii)Use and Maintenance of Devil
Canyon Access Road,Site
Roads and Railroad (**)
2.3.5 -Transmission Lines Impacts (**)
(a)Construction of
Transmission Line (**)•.
(i)Stage I Wataria Dam (**)•
(ii)Stage II Devil Canyon (**)
(b)Operation of the
Transmission Line (**)•••
(i)Stage I Watana Dam (**)•
(ii)Stage II Devil Canyon Dam and
.-'Sfage-nr-WafanaI5am"(*"~)
Page No.
E-3-2-238
E-3-2-238
E-3-2-238
E-3-2-239
E-3-2-239
E-3-2-239
E-3-2-239
E-3-2-242
E-3-2-244
E-3-2-244
E-3-2-245
E~3-2-246
E-3-2-246
E-3-2-246
E-3-2-249
E-3-2-249
E-3-2-249
E=3=2"'250
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2.4 -Mitigation Issues and Mitigating Measures (**)
851021
2.4.1 -Approach to Mitigation (**)
2.4.2 -Selection of Project
Evaluation Species (**)••
(a)Devil Canyon -to Cook Inlet Reach (**)
(b)Ttnpoun.dlll.en.t Area (**)• • • • • •
.··2.4.3-Mitigat ionof-"Const ruc t ion Impacts
Upon Fish and Aquatic Habitats (*)
vi
E-3-2-25l
E-3-2-251
E-3-2-252
E-3-2-254
E-3-2-255
E-3-2-256
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Title
851021
2.4.4
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,.&BOTAIlICAL RESOURCES
TABLE OF CONTENTS (cont'd)
(a)Stream Crossings and
Encroachments (*)••••
(i)Impact Issue(*)
(ii)Mitigation(*)••
(b)Increased Fishing Pressure (*)•
(i)Impact Issue (*)••••••
(ii)Mitigation (*)•••••
(c)E ro sion Control (*)
(i)Impact Issue (*)
(ii)Mitigation (*)••••
(d)Material Removal (*)
(i)Impact Issue (*)
(ii)Mitigation (**)•••••••
(e)Oil and Hazardous Material Spills (*)
(i)Impact Issue (*)••••
(ii)Mitigation (*)
(f)Water Removal (*)••••
(i)Impact Issue (*)
(ii)Mitigation (*)
(g)Blasting (*)••••••
(i)Impact Issue (*)
(ii)Mitigation (*)
(h)Susitna River Diversions (*)
(i)Impact Issue (*)
(ii)Mitigation (*)
(i)Water Quality Changes (*)
(i)Impact Issue (*)
(ii)Mitigation (*)••••
(j)Clearing the Impoundment Area (*)
(i)Statement of Issue (*)
(ii)Migitation (*)
-Mitigation of Filling and
Operation Impacts (***)• •
(a)Mitigation of Downstream Impacts
Associated with Flow Regime (***)
(i)Impact Issue (***)
(ii)Measures to Avoid
Impacts (***)• • •
(iii)Measures to Minimize
Impacts (***)••••••••
(iv)Rectification of Impacts (**)
vii
Page No.
E-3-2-257
E-3-2-257
E-3-2-257
E-3-2-259
E-3-2-259
E-3-2-259
E-3-2-259
E-3-2-259
E-3-2-260
E-3-2-260
E-3-2-260
E-3-2-26l
E-3-2-262
E-3-2-262
E-3-2-262
E-3-2-263
E-3-2-263
E-3-2-263
E-3-2-264
E-3-2-264
E-3-2-264
E-3-2-264
E-3-2-264
E-3-2-264
E-3-2-265
E-3-2-265
E-3-2-265
E-3-2-265
E-3....2-265
E-3-2-265
E-3-2-266
E-3-2-266
E-3-2-266
E-3-2-267
E-3-2-268
E-3-2-271
EXHIBITE -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
TABLE OF CONTENTS (co nt 'd)
Title
(v)Reduction of Impacts
Over Time (0)• • • • • • • •
(vi)Compensation for Impacts (**)
(b)Mitigation of Downstream Impacts
Associated with Altered Water
Temperature Regime (*)•••.•
(i)Impact Issue (*)•••••
(ii)Measures to Avoid Impacts (0)
(iii)Measures to Minimize
Impac ts (*)• • • • . • •
(c)Mitigation of Inundation ~mpacts on,
Mainstem and Tributary Habitats (**)
(0 Impact Is.sue (**)• • • •
.(ii)Measures to Avoid Impacts (0)
(iii)Measures to Minimize
!mpacts (*)• • • •
(iv)Measures to Rectify
Impacts (*)• • • • • • • • •
(v)Reduction of Impacts (0)
vi Compensation for
Impacts ~***). . . • . .
(d)Mitigation of Downstream Impacts
Associated with Nitrogen
Supersaturation (0)••••
(i)Impact Issue (0)•••••.•
(ii)Measures to Avoid Impacts (0)
(iii)Measures to Minimize
!mpacts (0)••~••
2.4.S-Cumu1-ativeEffectiveness-of
........._-_..___-..__.._---·Mi-t-i.ga.t-ions--~o-)_··•.-•...•-.-•.-•._-•._.•-......_-•..-•..•..
(a)Construction Mitigation (0)
(b)Operation Mitigation (**)
(i)Mitigations of Access and
Impoundment Impacts (**)
(ii)Mitigation of
.DC:>WI.l.~.t.re~III..Imp ac t s
2.5 ...Aquatic Studies Program (~*)
2.5.1 -Preconstruction Phase (**)
2.5.2 -Construction Phase (*)
2.5.3 -Filling and Operation Phases (0)
851021 viii
.._.._..._.-..._.._.._...._.._.•.....__.....__....-._._._.---
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
TABLE OF CORTERTS (co nt 'd)
Title
2.6 -Monitoring Studies (**)••••
2.6.1 -Construction Monitoring (***)
2.6.2 -Long-term Monitoring (***)
2.6.3 -Long-term Monitoring Elements (***)
(a)Dissolved Gas Supersaturation (***).
(b)Temperature/Ice (***)• • • •
(c)Turbidity/Sediment (***)••
(d)Heavy Metal Concentrations
in Fish (***)••••••
(e)Dissolved Oxygen,pH,Organic
Nitrogen (Total,Particulate -
Organic and Inorganic,and Dis-
solved),and Phosphorus (Total,
Particulate -Organic and
Inorganic,and Dissolved)(***)
(f)Water Quantity(***)•••••
(g)Fish Resources·(***)• • • • • •
(i)Impoundment Area (***)
(ii)Areas Downstream of
the Project (***)•
(h)Monitoring of Structural Habitat
Modifications (***)••••••••
(i)Fluvial Geomorphology (***)
(j)Special Monitoring Studies (***)
(k)Contingency Planning (***)
2.7 -Cost of Mitigation (***)
2.8 -Agency Consultation on Fisheries Mitigation
Measures (*'*)•.••••.•••..••.
2.8.1 -u.S.Fish and Wildlife Service (**)•
(a)Construction Mitigations (0)•
(b)Operation Mitigations (**)• • •
(i)Reservoir Mitigations (**)
(ii)Downstream Mitigations (**)
2.8.2 -Alaska Department of Fish and Game (**)•
2.8.3 -Alaska Department of
Natural Resources (**)
2.8.4 -National Marine Fisheries Service (***)•
Page No.
E-3-2-287
E-3-2-288
E-3-2-292
E-3-2-294
E-3-2-295
E-3-2-296
E-3-2-298
E-3-2-299
:I
E-3-2-301
E-3-2-301
E-3-2-302
E-3-3-302
E-3-2-302
E-3-2-308
E-3-2-309
E-3-2-310
E-3-2-310
E-3-2-310
E-3-2-311
E-3-2-311
E-3-2-311
E-3-2-312
E-3-2-312
E-3-2-312
E-3-2-314
E-3-2-316
E-3-2-316
851021 ix
Nwnber
E.3.2.1
E.3.2.2
E.3.2.3
E.3.2.4
E.3.2.5
E.3.2.6
E.3.2.8
E.3.2.9
E.3.2.11
SUSITNA.·BYDROELEcrR.IC PROJECT
LICEBSE APPLICATION
EXHIBIT E·-CHAPTER 3
FISH,WILDLIFE,&BOTANICAL BESOUR.CES
LIST OF TABLES
Title
OOMMON AND SCIENTIFIC NAMES OF FISH SPECIES RE OORDED
FROM THE SUSITNA BASIN
COMMERCIAL CATCH OF UPPER COOK INLET SALIDN IN NUMBERS
OF FISH BY SPECIES,1954-1984
SUMMARY OF COMMERCIAL AND SPORT HARVESTS ON SUSITNA
RIVER BASIN ADULT SALMON RETURNS
ANNUAL SUSITNA BASIN SPORT FISH HARVEST AND EFFORT BY
FISHERY AND SPECIES,1978-1983
SPORT FISH HARVEST FOR SOUTHCENTRAL ALASKA AND SUSITNA
BASIN IN NUMBERS OF FISH BY SPECIES,1978-1983
ESCAPEMENTS BY SPECIES AND SAMPLING LOCATIONS FOR
1981-84
ANAliYSI:S'OF~~GFH-IDOK~SALM}N.AGE ..DATA'BY .PERCENT FR0M
ESCAPEMENT SAMPLES COLLECTED AT SEVERAL SUS ITNA RIVER
STATIONS
CHIOOOK SALMON PEAK SURVEY ESCAPEMENT OOUNTS OF SUSITNA
RIVER BASIN STREAMS FROM 1976 TO 1984
CHIOOOK SALIDN PEAK ES CAPE ME NT OOUNTS FOR TRIBUTARY
SJ'~AJ1S.A:ao V~.R:rYERMILE ..9.a.9......
--_......__....
NUMBER OF FISH,MEAN LENGTH,AND RANGE OF LENGTHS FOR
AGE 0+CHINOOK SALMON BY SAMPLING PERIOD ON THE SUSITNA
RIVER BETWEEN TALKEETNA AND DEVIL CANYON
ANALYSIS OF SOCKEYE SALIDN AGE DATA BY PERCENT FROM
ESCAPEMENT SAMPLES COLLECTED AT SEVERAL SUS ITNA RIVER
STATIONS'
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Number
E.3 .2.12
E.3.2.13
E.3.2.14
E.3.2.15
E.302.16
E.3 0 2.17
E.3.2.18
E.3.2.19
E.3.2.20
E.3.2.21
E.3.2.22
E.3.2.23
851021
EXHIBIT E -CHAPTER 3
FISH,W~DLIFE,&BOTABICAL RESOURCES
LIST OF ~LES (cont'd)
Table
ESTIMATED SOCKEYE SALMON ESCAPEMENTS TO SLOUGHS ABOVE
RIVERMILE 98.6
SUMMARY OF LENGTHS OF AGES 0+AND 1+JUVENILE SOCKEYE
SALMON BY SAMPLING PERIOD DURING 1984
ANALYSIS OF COHO SALMON AGE DATA BY PERCENT FROM
ESCAPEMENT SAMPLES COLLECTED AT SEVERAL SUSITNA RIVER
STATIONS
COHO SALMON PEAK ESCAPEMENT OJUNTS FOR TRIBUTARY STREAMS
ABOVE RIVER MILE 98.6
NUMBER OF FISH,MEAN LENGTH,AND RANGE OF LENGTHS FOR
COHO SALMON BY SAMPLING PERIOD ON THE SUSITNA RIVER
DURING 1984
ANALYSIS OF CHUM SALMON AGE DATA BY PERCENT FROM
ESCAPEMENT.SAMPLES COLLECTED AT SEVERAL SUS ITNA RIVER
STATIONS
CHUM SALIDN PEAK ESCAPEMENT COUNTS FOR TRIBUTARY STREAMS
ABOVE RIVER MILE 98.6
ESTIMATED CHUM SALMON ES CAPE ME NT S TO SLOUGHS ABOVE RIVER
MILE 98.6
PINK SALMON PEAK ESCAPEMENT OJUNTS FOR TRIBUTARY STREAMS
ABOVE RIVER MILE 98.6
FISH SPECIES INHABITING STREAMS WITH IN THE ACCESS AND
TRANSMISSION LINE CORRIDORS
FISH SPECIES INHABITING LAKES WITHIN THE ACCESS AND
TRANSMI S SI ON LINE CO RRI DORS
ARCTIC GRAYLING HOOK AND LINE CATCH IN TRIBUTARIES
WITHIN THE IMPOUNDMENT ZONE BY LOCATION AND MONTH
xi
EXHIBIT E -CHAPTER.3
FISH,WILDLIFE,&BOTABICAL RESOURCES
LIST OF TABLES (cont'd)j
)
Number
E.3.2.24
E.3.2.25
E.3.2.26
Table
ARCTIC GRAYLING POPULATION ESTIMATES FOR THE REACH OF
MAJOR TRIBUTARIES IN THE WATANA AND DEVIL CANYON
IMPO UNDMENT AREAS
PETERSEN POPULATION ESTIMATE FOR ARCTIC GRAYLING BY AGE
GROUP IN THE WATANA IMPOUNDMENT AREA,SUMMER 1982
SUSITNA HYDROELECTRIC PROJECT INFLUENCE OF MAINSTEM FLOW
AND WATER QUALITY ON CHARACTERISTICS OF AQUATIC HABITAT
TYPES
)
I
)-
;~1
E.3.2.27
E.3.2.28
E.3 .2.29
E.3.2.30
E.3.2.31
E.3.2.32
LOCATIONS OF NAMED TRIBUTARIES OF THE SUSITNA RIVER IN
THE RESERVOIR AREA
IMPORTANT USES OF HABITAT TYPES BY EVALUATION SPECIES
TOTAL SURFACE AREAS BY HABITAT TYPE WITHIN THE
TALKEETNA-DEVIL CANYON REACH OF THE SUS ITNA-RIVER
MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP I
MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP II
MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP III
,\
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E.3.2.33 MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP IV
I
I
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)
)
J
I 1
i
MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP V
xii
E.3.2.34
MIDDLE RIVER SITES IN REPRESENTATIVE GROUP VI
E.3.2.36 MIDDLE RIVER HABITAT SITES IN REPRESE NT ATI VE GROUP VII
E.3.2.37 MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP VIII
E.3.2.38 MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP IX
E.3.2.39 MIDDLE R.IVERHABI'1'AT SITES IN REPRESENTATIVE GROUP X
851021
Number
E.3.2.40
E.3.2 .41
E.3.2.42
E.3.2.43
E.3.2.44
Ed.2.45
E.3.2.46
E.3.2.47
E.3.2.48
E.3.2.49
E.3.2.50
E.3.2.51
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTABICAL RESOURCES
LIST OF ~tEs (cont'd)
Table
PRIMARY urILIZATION OF SENSITIVE HABITAT TYPES BY
EVALUATION SPECIES
roVER SUITABILITY CRITERIA REOOMMENDED FOR USE IN
JUVENILE CHINOOK HABITAT UNDER CLEAR AND TURBID WATER
OONDITIONS
JUVENILE CHIOOOK REARING HABITAT AVAILABILITY AT IFG AND
RJHAB MODELED SITES
RESPONSE OF CHUM SPAWNING HABITAT IN IFG ANDDIHAB
MODELLED SITES
RESPONSE OF CHUM SPAWNING HABITAT (WUA PER 1000 SQ.FT.)
AT IFG AND DIHAB MODELED SITES INCLUDED IN
REPRESENTATIVE GROUPS (RG)2,3,AND 4
RESPONSE FOR CHINOOK REARING HABITAT AREA TO DISCHARGE
IN EACH OF THE REPRESENTATIVE GROUPS
TOTAL CHIOOOK REARING HABITAT AREA RESPONSE TO DISCHARGE
IN ALL REPRESENTATIVE GROUPS AND IN REPRESENTATIVE
GRO UP S 2,3,AND 4
RESPONSE OF MIDDLE RIVER CHUM SPAWNING AREA REPRESENTED
IN IFG AND DIHAB MODELLED SITES
RESPONSE OF CHUM SPAWNING HABITAT IN REPRESENrATIVE
GROUPS 2,3,AND 4
TOTAL CHIOOOK REARING HABITAT IN ALL REPRESENTATIVE
GROUPS DURING SUMMER WEEKS UNDER NATURAL FLOW REGIME
TOTAL CHINOOK REARING HABITAT IN REPRESENTATIVE GROUPS
2,3,AND 4 DURING SUMMER WEEKS UNDER NATURAL FLOW
REGIME
SUMMARY OF LOCAL AND MAINSTEM DISCHARGES AT SUCCESSFUL
AND UNSUCESSFUL TIiRESHOLDS FOR CHUM SALMON ACCESS TO
SPAWNING HABITATS
xiii
EXHIBIT E -CHAPTER 3
FISH"WILDLIFE,&BOTANI CAL RESOURCES
--'----E.,3..2 -.,-58------,-.WATER--BODIES-TO--BE':"CROSSE-D~BY-TH'E-SUS-rT NA TRANSM'fS SION
LINE (HEALY TO FAIRBANKS)
Number
E.3.2.52
E.3.2.53
E.3.2.54
E.3.2.55
E.3.2.56
E.3.2.57
E.3.2.59
E.3.2.60
E.3.2.61
E.3.2.62
E.3.2.63
851021
LIST OF ~LES (cont'd)
Table
TOTAL CHUM SPAWNING HABITAT IN IFG AND DIHAB MODELLED
SITES DURING SUMMER WEEKS UNDER NATURAL FLOW REGIME
TOTAL CHUM SPAWNING HABITAT IN REPRESENTATIVE GROUPS 2,
3,AND 4 DURING SUMMER WEEKS UNDER NATURAL FLOW REGIME
TOTAL CHUM SPAWNING HABI TAT AVAILABLE FOR INCUBATION OF
EMBRYOS IN IFG AND DIHAB MODEL SITES UNDER NATURAL FLOW
REGIME
TOTAL CHUM SPAWNING HABITAT IN REPRESENTATIVE GROUPS 2,
3,AND 4 AVAILABLE FOR INCUBATION OF EMBRYOS DURING
EARLY WINTER WEEKS UNDER NATURAL FLOW REGIME
STREAMS CROSSED BY DENALI HIGHWAY (CANTWELL TO WATANA
ACCESS JUNCTION)
WATER BODIES TO BE CROSSEP BY THE SUSITNA TRANSMISSION
LINE (ANCHORAGE TO WILLOW)
FLOW CONSTRAINTS FOR ENVIRONMENTAL FLOW REQUIREMENT CASE
E-VI
ESTIMATED MONTHLY MEAN DISCHARGE,AT GOLD CREEK DURING
FILLING OF STAGE I -WATANA RESERVOIR
ESTIMATED CHANGES IN CHIOOOK REARING HABITAT AREA IN
REPRESENTATIVE GROUP 2 DUE TO FILLING UNDER DRY,
AVERAGE,AND WET OONDITIONS
ESTIMATED CHANGES IN CHIOOOK REARING HABITAT AREA IN
REPRESENTATIVE GROUPS 2,3,AND 4 DUE TO FILLING UNDER
DRY,AVERAGE,AND WET OONDITIONS
OOMPARISON OF PASSAGE,OONDITIONS OF PASSAGE REACHES
AmcTEIY-BY-"MA:I'N'STEM DISCHARGE---UNDER 'NA i'iJRAt AND FIL LI NG
WET OONDITIONS FOR DRY,AVERAGE,AND WET YEARS '
xiv
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Number
E.3.2.64
E.3.2.65
E.3.2.66
E.3.2.67
E.3.2.68
E.3.2.69
E.3.2.70
E.3.2.71
E.3.2.72
E.3 .2.73
E.3.2.74
851021
EXHIBIT E -CHAPTER.3
FISH,WTI.DLIFE,&BOTANICAL RESOURCES
LIST OF TABLES (cont'd)
Table
ESTIMATED CHANGES IN CHUM SPAWNING HABITAT AREA IN
MODELED SITES DUE TO FILLING OF THE WATANA -STAGE I
RESERVOIR
ESTIMATED CHANGES IN CHUM SPAWNING HABITAT AREA IN
REPRESENTATIVE GROUP'2 DUE TO FILLING UNDER DRY,
AVERAGE,AND WET roNDITIONS
ESTIMATED CHANGES IN CHUM SPAWNING HABITAT AREA IN
REPRESENTATI VE GROUP 3 DUE TO FILLING UNDER DRY,AVERAGE
AND WET roND ITIONS
ESTIMATED CHANGES IN CHUM SPAWNING HABITAT AREA IN
REPRESENTATIVE GROUP 4 DUE TO FILLING UNDER DRY,
AVERAGE,AND WET roNDITIONS
ESTIMATED CHANGES IN CHUM SPAWNING HABITAT AREA IN
AGGREGATE AREA OF REPRESENTATIVE GROUPS DUE TO FILLING
UNDER DRY,AVERAGE,AND WET CONDITIONS
PERIPHYTON GENERA EXPECTED TO COMPOSE THE MAJORI TY OF
AUFWUCHS COMMUNITIES IN MAINSTEM AND PERIPHERAL HABITATS
WITH SOLID SUBSTRATES OF THE SUSITNA RIVER,ALASKA
WEIGHTED USABLE .AREAS AND HABITAT INDICES FOR JUVENILE
CHINOOK SALMON IN LOWER SUSITNA RIVER MODEL SITES
SUMMARY OF EFFECTS OF STAGE I FILLING FLOWS ON JUVENILE
CHINOOK REARING HABITATS IN THE LOWER SUSITNA RIVER FROM
TALKEETNA TO roOK INLET
FEATURES OF NAMED TRIBUTARIES IN THE STAGE I -WATANA
RESERVOIR AREA
IDN1HLY MAXIMUM,MINIMUM AND MEAN FLOWS AT GOLD CREEK
(CFS)DURING STAGE I OPERATION
TOTAL CHUDOK REARING HABITAT AREA IN ALL REPRESENTATIVE
GROUPS DURING SUMMER WEEKS UNDER STAGE I FLOW REGIMES
AND,WINTER 1981-82 CLIMATE DATA
xv
Number
E.3.2.75
E.3.2.76
E.3.2.77
E.3.2.78
E.3.2.79
E.3.2.80
E.3.2.81
.E.3.2.82
E.3.2.83
E.3.2.84
-cE.3.2.85
851021
EXHIBIT E -CHAPTER.3
FISH,WILDLIFE,&BOTABICAL RESOURCES
LIST OF T&BLES (cont'd)
Table
'!OTAL CHIOOOK REARING HABITAT AREA IN REPRESENTATIVE
GROUPS 2,3,AND 4 DURING SUMMER WEEKS UNDER STAGE I
FLOW REGIME
SUMMARY OF ACCESS OONDITIONS FOR THE CHUM SPAWNING SITES
DURING STAGE I OPERATION BASED ON MEAN AVERAGE MONTHLY
FLOW,MAXIMUM AND MINIMUM AVERAGE MONTHLY FLOWS
TOTAL CHUM SPAWNING HABITAT IN IFG AND DIHAB MODEL SITES
DURING SUMMER MONTHS UNDER STAGE I FLOW REGIME
TOTAL CHUM SPAWNING HABITAT AREA IN REPRESENTATIVE
GROUPS 2 ,3,AND 4 DURING SUMMER WEEKS UNDER STAGE I
FLOW REGIMES
'!OTAL CHUM SPAWNING HABITAT AVAILABLE FOR INCUBATION OF
EMBRYOS IN IFG AND DIHAB MODEL SITES UNDER STAGE I FLOW
REGIME
TOTAL CHUM SPAWNING HABITAT IN REPRESENTATIVE GROUPS 2,.
...l,.AND 4:£\.vA:r:I.~~LE FORINCUBAJ·JQ~QJf~I1BR~(Q..Q.J2QR:rNG ..
EARLY WINTER WEEKS UNDER STAGE I FLOW REGIMES
SIMULATED STREAM TEMPERATURES,STAGE I WEATHER PERIOD:
SUMMER 1981,STAGED CONSTRUCTION,CASE E-VI FLOW
REQUIREMENTS ,STAGE·I
SIMULATED STREAM TEMPERATURES,WEA1HER PERIOD:SUMMER
1982,2001 ENERGY DEMANDS,CASE E-VI FLOW REQUIREMENTS,
STAGED "'CONS TRUCTIO-N;-S-TAGET--'..---....-..-------...-
STREAM TEMPERATURES,WEAnIER PERIOD:SUMMER 1981,
NATURAL CONDITIONS
STREAM TEMPERATURES,WEA1HER PERIOD:SUMMER 1982,
NATURAL CONDITIONS
MAXIMUM SIMULATED RIVER STAGES FOR CASE E-VIFLOW
-CONSTRAI--NTS,----I-NFI.OW---TEMPERA-l'uRE-MATGalNGSl'AGE I FLOW,
AND WINTER 1981-82 CLIMATE DATA
xvi
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Number
E.3.2.86
E.3.2.87
E.3.2.88
E.3.2.89
E.3.2.90
E.3.2.91
E.3.2.92
E.3.2.93
E.3.2.94
E.3.2.95
E.3.2.96
E.3.2.97
851021
EXHIBIT E -CHAPTER 3
,FISH,WILDLIFE,&BOTABICAL RESOURCES
LIST OF ~LES (cont'd)
Table
NATURAL AND ESTIMATED MEAN MONTHLY SUSPENDED SEDIMENT
OONCENTRATIONS AND TURBIDITY VALUES EXPECTED TO EXIT
WATANA RESERVOIR DURING STAGE I OPERATIONS
MO NTHLY MAX IMUM,MI NIMUM,AND MEAN FLOWS AT SUN SH INE
(CFS),STAGE I -WATANA LOW OPERATIONS
MONlHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT SUSITNA
(CFS)STATION,STAGE I -WATANA LOW OPERATION
JUVENILE CHIIDOK REARING HABITAT INDEX VALUE FOR MEAN
MONTHLY DISCHARGE AT THE SUNSHINE STAroN UNDER THE
NATURAL AND STAGE I OPERATING FLOW REGIMES
TOPOGRAPHICAL FEATURES OF SELECTED TRIBUTARIES OF THE
PROPOSED DEVIL CANYON IMPOUNDMENT,1982
MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT DEVIL
CANYON (CFS),STAGE II -WATANA·(LOW)-DEVIL CANYON
OPERATIONS
TOTAL CHINOOK REARING HABI TAT AREA IN ALL REPRESENTATIVE
GROUPS DURING SUMMER WEEKS UNDER STAGE II FLOW REGIME
TOTAL CHINOOK REARING HABITAT AREA IN REPRESENTATIVE
GROUPS 2,3,AND 4 DURING SUMMER WEEKS UNDER STAGE II
FLOW REGIME
SUMMARY OF ACCESS OONDITIONS FOR CHUM SPAWNING SITES
DURING STAGE II OPERATION BASED ON MEAN,MAXIMUM AND
MINIMUM AVERAGE M:>NlHLY FLOWS
TOTAL CHUM SPAWNING HABITAT IN IFG AND DIHAB MODEL SITES
DURING SUMMER MONTHS UNDER STAGE II FLOW REGIME
TOTAL CHUM SPAWNING HABITAT AREA IN REPRESENTATIVE
GROUPS 2,3,AND 4 DURING SUMMER WEEKS UNDER STAGE II
FLOW REGIMES
TOTAL CHUM SPAWNING HABITAT'AVAILABLE FOR INCUBATION OF
EMBRYOS IN IFG AND DIHAB MODEL SITES UNDER STAGE II FLOW
REGIME
xvii
EXHIBIT E -CHAPTER.3
FISH,WILDLIFE,&BOTARICAL RESOURCES
·E;3;Z;TOo······.MONTHLYMAXIMUM;··MINIMUM;ANDMEAN··FLOWSAT··GOLD CREEK
.~..-..--.~--__.··-···-·······-·-------(CFS-),·STA(m-I-n---WATkNA-(H·!"mi-)--~DE-VI-L--C.kNY0·N-···..--_..
OPERATIONS
Number
E.3.2.98
E.3.2.99
E.3.2.100
E.3.2.101
E.3.2.102
E.3.2.103
E.3.2.104
E.3.2.105
E.3.2.107
E.3.2.108
851021
LIST OF ~LES (cont'd)
Table
TOTAL CHUM SPAWNING HABITAT IN REPRESENTATIVE GROUPS 2,
3,AND 4 AVAILABLE FOR INCUBATION OF EMBRYOS DURING
EARLY WINTER WEEKS UNDER STAGE II FLOW REGIMES
SIMULATED STREAM TEMPERATURES,WEA 1HER PERIOD:SUMMER
1981,CASE E-VI FLOW CONSTRAINTS,STAGE II FLOW REGIME
SIMULATED STREAM TEMPERATURES,WEATHER PERIOD:SUMMER
1982,2002 CASE E-VI FLOW CONSTRAINTS,STAGE II FLOW
REGIME
MAXIMUM SIMULATED RIVER STAGES,FLOW CASE E-VI,
INFLOW-MATCHING,STAGE II FLOW REGIME
NATURAL AND ESTIMATED MEAN t-DN1HLY SUSPENDED SEDIMENT
<DNCENTRATIONS AND TURBIDITY VALUES EXPECTED TO EXIT
DEVIL CANYON RESERVOIR DURING STAGE II OPERATION
M:lN1HLY MAXIMUM,MINIMUM,AND MEAN FLOWS AT SUNSHINE
(CFS),STAGE II -WATANA (LOW)-DEVIL CANYON
OP1:RATIO NS
MONTHLY MAXIMUM ,MINIMUM,AND MEAN FLOWS AT SUSITNA
.STATION (CFS),STAGE II -WATANA (LOW)-DEVIL CANYON
OPERATIONS
FEATURES OF SELECTED TRIBUTARIES WITHIN 1HE STAGE III
WATANA IMPOUNDMENT
TOTAL CHIIDOK REARING HABITAT AREA IN ALL REPRESENTATIVE
GROUPS DURING SUMMER WEEKS UNDER EARLY STAGE III FLOW
REGIMES
TOTAL CHINOOK REARING HABITAT AREA IN ALL REPRESENTATIVE
GROtJP8DURINGSUMMERWEEKS UNDER LATE STAGE III FLOW
REGIME
xviii
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Number
E.3.2.109
E.3.2.110
E.3.2.111
E.3.2.112
E.3.2.113
E.3.2.114
E.3.2.115
E.3.2.116
E.3.2.117
E.3.2.118
851021
EXHIBIT E -CHAPTER 3
FISH,WILDL~,&BOTANICAL RESOURCES
LIST OF ~LES (cont'd)
Table
TOTAL CHINOOK REARING HABITAT AREA IN REPRESENTATIVE
GROUPS 2,3,AND 4 DURING SUMMER WEEKS UNDER EARLY
STAGE III FLOW REGIME
TOTAL CHINOOK REARING HABITAT AREA IN REPRESENTATIVE
GROUPS 2,3,AND 4 DURING SUMMER WEEKS UNDER LATE
STAGE III FLOW REGIME
SUMMARY OF ACCESS illNDITIONS FOR CHUM SPAWNING SITES
DURING STAGE II OPERATION BASED ON MEAN,MAXIMUM,AND
MINIMUM AVERAGE MONTHLY FLOWS
TOTAL CHUM SPAWNING HABITAT IN IFG AND DIHAB MIDEL SITES
DURING SUMMER MONTHS UNDER STAGE III FLOW REGIME
TOTAL CHUM SPAWNING HABITAT AREA IN REPRESENTATIVE
GROUPS 2,3,AND 4 DURING SUMMER WEEKS UNDER STAGE III
FLOW REGIMES
TOTAL CHUM SPAWNING HABITAT AVAILABLE FOR INCUBATION OF
EMBRYOS IN IFG AND DIHAB MODEL SITES UNDER STAGE III
FLOW REGIME
TOTAL CHUM SPAWNING HABITAT IN REPRESENTATIVE GROUPS 2,
3,AND 4 AVAILABLE FOR INCUBATION OF EMBRYOS DURING
EARL Y WINTER WEEKS UNDER STAGE III FLOW RE GIMES
SIMULATED STREAM TEMPERATURES,STAGE III,WEATHER
PERIOD:SUMMER 1981,CASE E-VI FLOW REQUIREMENTS,
STAGED CONSTRUCTION,SQ.FT.DRAWDOWN AT DEVIL CANYON,2
LEVELS OF PORTS
SIMULATED STREAM TEMPERATURES,STAGE III,WEATHER
PERIOD:SUMMER 1982,CASE E-VI FLOW REQUIREMENTS,
STAGED CONSTRUCTION,SQ.FT.DRAWDOWN AT DEVIL CANYON,2
LEVELS OF PORTS
MAXIMUM SIMULATED RIVER STAGES,CASE E-VI FLOW
ill NSTRAINTS ,INFLOW TEMPERATURE-MATCHING,AND WINTER
1981-82,CLIMATE DATA
xix
-...-~----.--.-----·-·-~--E·:·-3-:-2~r27--~--------ARCTIC'-GRA"YLING"POPULATION ESTIMATES IN SELECTED'
TRIBUTARIES OF THE WATANA IMPOUNDMENT ZONE
Number
E.3.2.1l9
E.3.2.120
E.3.2.121
E.3.2.122
E.3.2.123
E.3.2.124
E.3.2.125
E.3.2.126
E.3.2.128
E.3.2.129
E.3.2.130
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
LIST OF TABLES (co nt I d)
Table
NATURAL AND ESTIMATED MEAN MONTHLY SUSPENDED SEDIMENT
OONCENTRATIONS AND TURBIDI'IY VALUES EXPECTED TO EXIT
DEVIL CANYON RESERVOIR DURING STAGE III OPERATION
MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT SUNSHINE
(CFS),STAGE III -WATANA (HIGH)-DEVIL CANYON
OPERATIONS
MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT SUSITNA
STATION (CFS),STAGE -III -WATANA (HIGH)-DEVIL CANYON
OPERATIONS
JUVENILE CHINOOK REARING HABITAT INDEX VAbUES FOR MEAN
MONTHLY DISCHARGE AT THE SUNSHINE STATION 11 UNDER THE
NATURAL AND STAGE III OPERATING FLOW REGIMES
IMPACT ISSUES AND PROPOSED MITIGATION FEATURES FOR
ANTICIPATED FILLING AND OPERATIONAL IMPACTS TO AQUATIC
HABITATS,S USITNA HYDROELECTRIC PROJECT
ESTIMATED OOST FOR WATER QUALITY AND FISHERIES
M()NI-'l'(}Ri-NG-{I~N-1-98S~-DOLLARS-)-DURING~CONS'l'RUC-'I'ION (1986
TO 2012)
ALASKA DEPARTMENT OF FISH AND GAME STANDARDS FOR
BLASTING NEAR AN ANADROMOUS FISH STREAM MEASURED IN
FEEt!1
PROPOSED FISHERIES MITIGATIONS WITH ESTIMATED CAPITAL
AND ANNUAL OPERATING AND MAINTENANCE OOSTS,----.".'._--_.__..'......•-,....,'---,-.-.,--"-"-'-'-',,_-....•._.__._._-,-_,.__•....,.__..-._..,"_._----._~----_.,."_._..•__.___.__._-
ARCTIC GRAYLING POPULATION ESTIMATES IN SELECTED
TRIBUTARIES OF THE DEVIL CANYON IMPOUNDMENT ZONE
ANNUAL OPERA'l'ING COSTS OF LONG-TERM MONITORING PROGRAM
IN 1985 -DOLLARS
SCHEDULE FOR LONG-TERM AQUATIC IDNITORING PLAN
xx
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Number
E.3.2.131
E.3.2.132
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANI~·RESOURCES
LIST OF TABLES (cont'd)
Table
SUMMARY OF ESTIMATED OOSTS FOR HABITAT IDDIFICATION
MEASURES IN SELECTED SLOUGHS AND SIDE CHANNELS
SCHEDULE FOR IMPLEMENTING AQUATIC MITIGATION PROGRAM
xx~
Number
E.3.2.1
E.3.2.2
E.3.2.3
E.3.2.4
E.3.2.5
E.3.2.6
E.3.2.7
-E.3-.2.8
E.3.2.9
E.3.2.10
E.3.2.11
,,:::::,:=3".:,:2.12
EXHIBIT E CHAPTER 3
FISH,WILDLIFE,&:B01'ANICAL RESOURCES
LIST OF FIGURE S
Title
UPPER,MIDDLE AND LOWER DRAINAGE OF THE SUSITNA
PROJECT AREA
S USITNA RIVER AND MAJOR TRIBUTARIES FROM MOUTH TO
LITTLE WILLOW CREEK
SUSITNA RIVER AND MAJOR TRIBurARIES FROM IDNTANA
CREEK TO DEVIL CANYON
SUSITNA RIVER AND MAJOR TRIBUTARIES FROM DEVIL
CANYON TO DENALI HIGHWAY
POPULATION ESTIMATES OF ADULT SALIDN IN SUSITNA
RIVER
UPPER COOK INLET COMMERCIAL SALIDN MANAGEMENT AREA
TIMING OF LIFE STAGES OF SALIDN IN THE SUSITNA RIVER
,FROM TALKEETNA 'ID DEVIL CANYON
SLOUGH AND'l'RI-BUTAR¥INDEX AREA,PEAKSPAWNINGOOUN'l'S
SLOUGH AND TRIBUTARY INDEX AREA,PEAK SPAWNING CDUNTS
SLOUGH AND TRIBUTARY INDEX AREA,PEAK SPAWNING CDUNTS
SLOUGH AND TRIBUTARY INDEX AREA,PEAK SPAWNING CDUNTS
I
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E.3.2.14
E.3.2.15
E.3.2.16
851021
STREAM CROSSING SITES ALONG THE NORTHERN PORTION OF
THE PROPOSED WATANA ACCESS CORRIDOR
STREAM CROSSING SITES ALONG THE SOUTHERN PORTION OF
THE PROPOSED WATANA ACCE;SS CORRIDOR,INCL UDING THREE
STUDY REACHES OF DEADMAN CREEK
STREAM CROSSING SITES ALONG THE EASTERN PORTION OF THE
PROPOSED DEVIL CANYON ACCESS AND TRANSMISSION CORRIDOR
xxii
)
1
I
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•.I
Number
E.3.2.17
E.302.18
E.3.2.19
E.3 0 2o20
E.3.2.21
E.3.2.22
E.3.2.23
E.3.2.24
E.3.2.25
E.3.2.26
E.3.2.27
E.3.2.28
E.3.2.29
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
LIST OF FIGURES (cont'd)
Title
STREAM CROSSING SITES ALONG THE WESTERN PORTION OF THE
PROPOSED DEVIL CANYON ACCESS AND TRANSMISSION
CORRIDOR,AND THE PROPOSED GOLD CREEK RAIL ACCESS
CO RRI OOR
DELINEATION OF HABITAT AREAS IN THE MIDDLE S USITNA
RIVER,RIVER MILE 101 TO 102
DELINEATION OF HABITAT AREAS IN THE MIDDLE S USITNA
RIVER,RIVER MILE 102 TO 104
DELINEATION OF HABITAT AREAS IN mE MIDDLE SUSITNA
RIVER,RIVER MILE 105 TO 107
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 108 TO 110
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA
RIVER,RIVER MILE III TO 112
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 113 TO 115
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 116 TO 118
DELINEATION OF HABITAT AREAS IN THE MIDDLE S USITNA
RIVER,RIVER MILE 119 TO 121
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 122 TO 124
DELINEATION OF HABITAT AREAS IN mE MIDDLE SUSITNA
RIVER,RIVER MILE 124 TO 126
DELINEATION OF HABITAT AREAS IN mE MIDDLE SUSITNA
RIVER,RIVER MILE 127 TO 129
DELINEATION OF HABITAT AREAS IN mE MIDDLE SUSITNA
RIVER,RIVER MILE 130 TO 132
xxiii
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
'l
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DELINEATION OF HABITAT AREA IN 'IRE MIDDLE SUSITNA
RIVER,RIVER MILE 136 TO 138
LIST OF FIGURES (cont'd)
DELINEATION OF HABITAT AREA IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 144 TO 146
DELINEATION OF HABITAT AREA IN 'IRE MIDDLE SUSITNA
RIVER,RIVER MILE 142 TO 144
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 133 TO 136
DELINEATION OF HABITAT AREA IN THE MIDDLE SUSITNA
RIVER,RIVER MILE 139 TO 141
DENSI1Y DISTRIBUTION OF JUVENILE COHO SALMON BY
MICROHABITAT TYPE ON THE SUSITNA BETWEEN THE CHULITNA
RIVER CONFLUENCE AND DEV.IL CANYON,MAY 1HROUGH
NOVEMBER,1983.
Title
JUVENILE CHIIDOK SALIDN MEAN CATCH PER CELL AT SIDE
SLOUGHS AND SIDE CHANNELS BY SAMPL~NG PERIOD,MAY
THROUGH roVEMBER,1983.
DENSI1Y DISTRIBUTION OF JUVENILE SOCKEYE SALMON BY
.~.~MICROHABITAT.1YPEONTHE~SUSITNARIVER.BETWEEN·THE ..
CHULITNA RIVER 00 NFLJmlLGE_A1l!D_D.E.YIL_..cANY.QN.,__MAY___._
THROUGH OCTOBER 1983.
E.3.2.39
E.3.2.38
E.3 .2.37
E.3.2.30
E.3.2.35
E.3.2.31
E.3.2.34
E.3.2.32
Number
E.3.2.33
DELINEATION OF HABITAT AREA IN 'IRE MIDDLE SUSITNA
RIVER,RIVER MILE 147 TO 149
E.3.2.36 DENSITY DISTRIBUTION AND JUVENILE CHIIDOK SALMON BY
MICROHABITAT 1YPE ON THE SUSITNA,RIVER BETWEEN THE
c~~~---_c~~~-~-'-'~~~~--CHULITNA"~RIVER~ooNFLUENCE~AND--DEVIL CANYON;11A.Y~
THROUGH NOVEMBER 1983.
E.3.2.40
--~.-._"'--""~""--""--'-
DENSITY DISTRIBUTION OF JUVENILE CHUM SALMON BY
__.,~_••..,_"',_._.__".,,",._,,_..__••.,•••.•"-~__.•"_..•__,.~".•_.,,.0--'"_..,,_.....__._.•_..._..~._"._,,_._,__..•..'""""."•••',"",.'..__•__••_""'..__
MICROHABITAT 1YPE ON THE SUSITNA RIVER BETWEEN THE
CHULITNA.RIVER ooNFLUENCE AND DEVIL CANYON,MAY
THROUGH OCTOBER 1983
i
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851021 xxiv
,I~i
:IIJ
Number
E.3.2.41
E.3.2.42
E.3.2.43
E.3.2.44
E:.3.2.45
E.3.2.46
E.3.2.47
E.3.2.48
E.3.2.49
E.3.2.50
E.3.2~51
E.3.2.52
E.3.2.53
851021
EXHIBIT E -CHAPTER 3
FISH,1ilILDLIFE,&BOTANICAL RESOURCES
LIST OF FIGURES (cont'd)
Title
JUVENILE SOCKEYE SALMON MEAN CATCH PER CELL AT THREE
MICROHABITATS BY SAMPLING PERIOD,MAY THROUGH OC1DBER,
1983
JUVENILE mHO SALIDN MEAN CATCH PER CELL AT SIDE
SLOUGHS AND SIDE CHANNELS BY SAMPLING PERIOD,MAY
THROUGH NOVEMBER 1983
JUVENILE CHUM SALIDN MEAN CATCH PER ALL .AT THE FOUR
MACROHABITATS BY SAMPLING PERIOD,MAY THROUGH OC1DBER,
1983
SURFACE AREA RESPONSES TO MAINSTEM DISCHARGE IN THE
TALKEETNA.-1D-DEVIL CANYON REACH OF THE SUSITNA.
FLOW CHART FOR CLASSIFYING THE TRANSFORMATION OF
AQUATIC HABITAT 'IYPES BETWEEN TWO FLOWS
JUVENILE CHIOOOK SALIDN SUITABILITY CRITERIA FOR DEPTH
APPLICABLE 1D CLEAR AND TURBID WATER HABITATS
JUVENILE CHIOOOK SALMON SUITABILITY CRITERIA FOR
VELOCITY APPLICABLE TO CLEAR AND TURBID WATER
HABITATS
mVER SUITABILITY CRITERIA RECOMMENDED FOR USE IN
MODELING JUVENILE CHINOOK HABITAT UNDER CLEAR AND
TURBID WATER mNDITIONS
DEPTH SUITABILITY CURVE FOR CHUM SALIDN SPAWNING
VELOCI'IY SUITABILI'IY CURVE FOR CHUM SALMON SPAWNING
COMBINED SUBSTRATE/UPWELLING SUITABILI'IY CURVE FOR
CHUM SALMON SPAWNING
JUVENILE CHlOOOK HABITAT QUALITY RESPONSES TO MAINSTEM
DISCHARGE FOR MODELLED SITES IN THE MIDDLE SUSITNA.
RIVER
TOTAL HABITAT AREA RESPONSE CURVES IN CHUM SPAWNING
SITES USING IFG AND DlHAB MODELS
xxv
..--.-..-...-....--...-.....-....·-----E-.3.2.6:3-----------RE-S.P0NS-E-0F--(3H-UM-·S-PAWN-ING--ARE-A-T0---F-I:i0W---IN----·--·-·--·-·-..--.----..
REPRESENTATIVE GROUPS 2,3,4
Number
E.3.2.54
E.3.2.55
E.3.2.56
E.3 .2.57
E.3.2.58
E.3·.2.59
E.3.2.60
E.3.2.61
E.3.2.62
E.3.2.64
E.3 .2.65 ..----.-
E.3.2.66
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL,RESOURCES
.LIST OF FIGURES (co nt 'd)
Title
HABITAT QUALI1Y RESPONSE OF CHUM SALIDN AREAS
(MODELED SITES)
ADJUSTMENT OF THE WEIGHTED USABLE AREA (WUA)CURVE OF
A MODELED SPECIFIC AREA TO SYNTHESIZE THE WUA CURVE OF
A NONMDDELED SPECIFIC AREA TO ACCOUNT FOR DIFFERENCES
IN STRUCTURAL HABITAr QUALITY BETWEEN THE TWO SPECIFIC
AREAS
CUMULATIVE JUVENILE CHIOOOK HABITAT AREA RESPONSE TO
MAINSTEM DISCHARGE IN EACH REPRESENTATIVE GROUP
RESPONSE OF REARING HABITAT AREA TO FLOW IN ALL
REPRESENTATIVE.GROUP.S COMBI NED
RESPONSE OF REARING HABITAT AREA TO FLOW IN
REPRES ENTATIVEGROUPS 2,3,4
RESPONSE OF CHUM SPAWNING AREA TO FLOW IN IFG AND
DIHAB MODEL SITES
RESPONSE OF CHUM SPAWNING AREA TO FLOW IN
REPRESENTATIVE GROUP 2
RESPONSE OF CHUM SPAWNING AREA TO FLOW IN
REPRESENTATIVE GROUP 3
RESPONSE OF CHUM SPAWNING AREA TO FLOW IN
REPRESENTATIVE GROUP 4
CHINOOK REARING HABITAT AREA UNDER NATURAL FLOW REGIME
IN ALL REPRESENTATIVE GROUPS
CHINOOK REARING HABITAT AREA.UNDER NATURAL.FLOW_REGIME
IN REPRESENTATIVE GROUPS 2,3,4
SALM:>N PASSAGE CRITERIA THRESHOLDS
xxvi
Number
E.3.2.67
E.3.2.68
E.3.2.69
E.3.2.70
E.3.2.71
E.3 .2.72
E.3.2.73
E.3.2.74
E.3.2.75
E.3.2.76
E.3 .2.77
E.3.2.78
E.3.2.79
E.3.2.80
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
.LIST OF FIGURES {cant 'd)
Title
CHUM SPAWNING AREA IN IFG AND DIHAB IDDEL SITES UNDER
NA TURAL FLOW REGIME
CHUM SPAWNING AREA,IN REPRESENTATIVE GROUPS 2,3,4
UNDER NATURAL FLOWS
CHUM INCUBATION AREA IN IFG AND DIHAB IDDEL SITES
UNDER NATURAL FLOWS
CHUM INCUBATION AREA IN REPRESENTATIVE GROUPS 2,3,4
UNDER NATURAL FLOWS
WATER BODIES TO BE INUNDATED BY STAGE I WATANA
RESERVOIR
WATANA RESERVOIR OUTFLOW TEMPERATURE DURING INITIAL
FILLING
JUVENILE CHINOOK WEIGHTED USABLE AREA IN
REPRESENTATIVE SITES LOCATED IN THE LOWER RIVER
WATANA WATER SURFACE ELEVATION IDN1HLY SUMMARY
CHINOOK REARING HABITAT AREA UNDER STAGE I FLOW REGIME
IN ALL REPRESENTATIVE GROUPS
CHIOOOK REARING HABITAT AREA UNDER STAGE I FLOW REGIME
IN REPRESENTATIVE GROUPS 2,3,4
CHUM SPAWNING AREA IN IFG AND DIHAB IDDEL SITES UNDER
STAGE I FLOWS
CHUM SPAWNING AREA IN REPRESENTATIVE GROUPS 2,3,4
UNDER STAGE I FLOWS
CHUM INCUBATION AREA IN IFG AND DIHAB IDDEL SITES
UNDER STAGE I FLOWS
CH UM INCUBATION AREA IN REP RES E NTATI VE GRO UPS 2,3,4
UNDER STAGE I FLOWS
xxvii
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL.RESOURCES
Number
E.3.2.81
E.3.2.82
E.3.2.83
E.3.2.84
E.3.2.85
E.3.2.86
E.3.2.87
E.3.2.88
E.3.2.89
E.3.2.90
E.3.2.91
LIST O~FIGURES (cont'd)
Title
STAGE I WATANA RESERVOIR OUTFLOW TEMPERATURE
SUSITNA RIVER PROGRESSION OF ICE FRONT AND ZERO DEGREE
ISOTHERM
AGGREGATE CHINOOK REARING HABITAT QUALITY INDEX FOR
LOWER RIVER SIDE CHANNEL/SIDE SLOUGH HABITATS
AGGREGATE CHINOOK REARING HABITAT QUALITY INDEX FOR
LOWER RIVER TRIBUTARY MOUTH HABITATS
WATER BODIES TO BE INUNDATED BYL STAGE II DEVIL CANYON
RESERVOIR
DEVIL CANYON WATER SURFACE ELEVATION,M:lNTHLY SUMMARY
WATANA WATER SURFACE ELEVATION,IDNTHLY SUMMARY
CHINOOK REARING HABITAT -AREA UNDER STAGE"II FLOW
REGIME IN ALL REPRESENTATIVE GROUPS
CHINOOK REARING HABITAT AREA UNDER STAGE II FLOW
REGIME IN REPRESENTATIVE GROUPS 2,3,4
CHUM SPAWNING AREA IN IFG AND DlHAB IDDEL SITES UNDER
STAGE II FLOWS
CHUM SPAWNING AREA IN REPRESENTATIVE GROUPS 2,3,4
UNDER STAGE II FLOWS
-·~~~-~~-·~E-;-3--;;·2-;-92~-~--~-~-.--CH-UM-r_NeuBAT-r0N~~ARE_A-r_N-r_F~-AND-DIHkB~~illDEI:;~-S-I~'I'E_S-~-~~~-
UNDER STAGE II FL OWS
E.3.2.93 CHUM INCUBATION AREA IN REPRESENTATIVE GROUPS 2,3,4
UNDER STAGE II FLOWS
E.3.2.94 SIMULATED S USITNARIVERcTEMPERATURES,RIVER MILE 150
E"3,,2.-95--~...-~-SIMULATED--SUSI'fNA'-RIVER-TEMPERATURES,RIVER MILE 130
E.•3.2.96 SIMULATED SUSITNA RIVER TEMPERATURES,RIVER MILE 100
851021 xxviii
(
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Number
E.3.2.97
E.3.2.98
E.3.2.99
E.3.2.100
E.3.2.101
E.3.2.102
E.3.2.103
E.3.2.104
E.3.2.105
E.3.2.106
E.3.2.107
E.3.2.108
E.3.2.109
E.3.2.110
E.3.2.111
E.3.2.112
851021
EXHIBIT E -CHAPTER 3
FISH,WILDLIFE,&BOTANICAL RESOURCES
LIST OF FIGURES (cont'd)
Title
S USI TNA RI VER PRO GRES S IO N OF I CE FRO NT AND ZERO DE GREE
ISOTERM
TEMPERATURE TOLERANCE FOR CHIIDOK SALM:>N
TEMPERATURE TOLERANCE FOR SOCKEYE SALM:>N
TEMPERATURE TOLERANCE FOR mHO SALMON
TEMPERATURE TOLERANCE FOR CHUM SALM:>N
TEMPERATURE TOLERANCE FOR PINK SALM:>N
WATER BODIES TO BE INUNDATED BY STAGE III WATANA
RESERVOIR
WATANA WATER SURFACE ELEVATION MONTHLY SUMMARY
DEVIL CANYON WATER SURFACE ELEVATION,M:>"NTHLY SUMMARY
CHINOOK REARING HABITAT AREA UNDER EARLY STAGE III
FLOW REGIME IN ALL RE PRES ENTA TlVE GROUPS
CHUDOK REARING HABITAT AREA UNDER LATE STAGE III FLOW
REGIME IN ALL REPRESENTATIVE GROUPS
rn:lmOK REARING HABITAT AREA UNDER EARLY STAGE III
FLOW REGIME IN REPRESENTATIVE GROUPS 2,3,4
CHINOOK REARING HABITAT AREA UNDER LATE STAGE III FLOW
REGIME IN REPRESENTATIVE GROUPS 2,3,4
CHUM SPAWNING AREA IN IFG AND DIHAB MODEL SITES UNDER
EARLY STAGE III FLOWS
CHUM SPAWNING AREA IN IFG AND DlHAB MODEL SITES UNDER
LATE STAGE III FLOWS
CHUM SPAWNING AREA IN REPRESENTATIVE GROUPS 2,3,4
UNDER EARLY STAGE III FLOWS
xxvix
EXHIBIT E -CHAPTER 3
FISH~WILDLIFE ~&BOTANICAL RESOURCE
LIST OF FIGURES (cont'd)
Number Title'..::.:;..:;,:;;,.~-----------------
E.3.2.113 CHUM,SPAWNING AREA IN REPRESENTATIVE GROUPS 2,3,4,
UNDER LATE STAGE III FLOWS
E.3.2.114 CHUM INCUBATION AREA IN IFG AND DlHAB MODEL SITES
UNDER EARLY STAGE III FLOWS
E.3.2.115 CHUM INCUBATION AREA IN IFG AND DlHAB MODEL SITES
UNDER LATE STAGE III FLOWS
E.3.2.116 CHUM INCUBATION IN REPRESENTATIVE GROUPS 2,3,4 UNDER
EARLY STAGE III FLOWS
E.3.2.117 CHUM INCUBATION AREA IN REPRESENTATIVE GROUPS 2,3,4
.'m'lDER .LATE STAGE III ..FLOWS
E.3.2.118 SUSITNA RIVER PROGRESSION OF ICE FRONT &ZERO DEGREE
ISOTHERM
E.3.2.119 DIAGRAM OF FISH STREAM .CROSSING
_'Il:!3~-!-1~0 ."~RE!ll\BIL_I.'I'k.TEl>_~O~J>W·SI1''Il:..~
E.3.2.121 FISH PASSAGE MITIGATION UTILIZING BARRIERS
E.3.2.122 FISH PASSAGE MITIGATION BY MOD:rFYING CHANNEL WIDTH
E.3.2.123 OVERTOPPINGPREVE:Nr,rION MITIGATION BY INCREASING BERM
HEIGHT
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E.3.2.125
851021
.....FLOW"CHART FOR-RANKING'STTES:FORMITIGATION DECISION''''
OONCENTRATIONS OF DISSOLVED GASSES IN DEVIL CANYON
RAPIDS COMPLEX
xxx
i
i I
2 -FISH RESOURCES OF THE SUSITNA RIVER DRAINAGE (**)
2.1 -Overview of the Resources (**)
2.1.1 -Description of the Study Area for Fish Resources (**)
The study area for the Susitna Hydroelectric Project fish studies
includes the Susitna River mainstem,side channels,side
sloughs,upland sloughs and tributaries (Figure E.3.2.l).From
the terminus of Susitna Glacier in the Alaska Mountain Range to
its mouth in Cook Inlet,the Susitna River flows approximately
318 miles (530 km)and drains 19,600 square miles (50,900 square
kilometers).The mainstem and major tributaries of the Susitna
River,including the Maclaren,Chulitna,Talkeetna and Yentna
Rivers,originate in glaciers and carry a heavy load of glacial
flour during the ice-free months.There are many smaller,clear
water tributaries that are perennially silt-free,except during
floodflows,including Tyone River,Oshetna River,Portage Creek,
Indian River,Kroto Creek (Deshka River)and Alexander Creek
(Figures E.3.2.2 to E.3.244).
Streamflow is characterized by moderate to high flows between May
and September and low flows from October to April.High summer
discharges result from snowmelt,rainfall and glacial melt.
Winter flows are almost entirely ground water inflow (see Exhibit
E,Chapter 2,Section 2.2.3).Freezeup begins in the higher
regions in early October,and most of the river is ice free by
late May.
Three study reaches have been defined for baseline data gathering
and impact analysis based upon stream morphology,flow regime and
anticipated impacts.These study reaches are:the impoundment
from the Oshetna River (River Mile RM 236)to Devil Canyon (RM
152);Devil Canyon to Talkeetna (RM 98);and Talkeetna to Cook
Inlet (RM 0).These are commonly referred to as the impoundment
zone and the middle and lower river reaches,respectively.
The Susitna River upstream of the Watana Reservoir will not be
affected by the project and,therefore,is not included in the
study area.In the impoundment zones (Watana and Devil Canyon
Reservoirs),the existing flowing water habitats will become
lake-like habitats in the reservoirs.Although fish resources
will continue to exist in the reservoirs,it is expected that the
productivity will be relatively low because the reservoirs will
remain quite turbid throughout the year.Downstream from the
reservoirs,the flow regime,temperature regime,water quality
characteristics and ice processes are expected to be altered by
the project and therefore will affect fish resources.The most
affected reach downstream from the dams is the middle Susitna
River from the Devil Canyon Dam Site to Talkeetna at the
851021 E-3-2-1
confluence with the Chulitna River.These changes are discussed
in detail in Exhibit E Chapter 2 Section 4 and the effects to
fish resources are discussed in detail in Section 2.3.Measures
to mitigate for the expected adverse effects are described in
Section 2.4.Effects to fish resources in the lower river
(between Talkeetna and Cook Inlet)are not expected to be as
great as those expected in the middle river.Basically,the
effects expected in the lower river are less because the changes
induced by the project will be masked by the flow,temperature
and water quality regimes contributed by the Chulitna and
TalkeE!tna Rivers as well as numerous other tributaries flowing
into the lower river.
2.1.2 -Data collection and Analysis Methods (**)1
851021
(a)Anadromous Adult Investigations (**)
Methods utilized from 1981 through 1985 to enumerate adult
salmon within the Susitna River drainage included
side-scan sonar moni toring,fishwheel monitoring,tag and
recapture estimates and ground/aerial spawning surveys.
Side scan sonars and fishwheels were used to determine the
upstream migration timing of SOCkeye,pink,chum,and coho
salmon in the Susitna River from July through early to
mid-September 1981 and 1982 •.Sampling locations included
Susitna Station (RM 26),and Yentna Station (Yentna RM 04),
Sunshine Station (RM 80)located in the lower river,and .
Talkeetna Station (RM 103)located in the middle river
(ADF&G 1985a)as shown in Figures E.3.2.2 and E.3.2.3.
Fi~hwheels were used from 1981 through 1984 at these
stations,but sonars were only used for 1983 and 1984 at the
Susitna and Yentna Stations.Fishwheels were also operated
at Curry Station (RM 120)in the middle river from 1981
through 1984 and at Flathorn Station (RM 20)in the lower
river during the 1984 season,but without associated sonar
co.unt e rs .Wh(:UL:f:ish:wh~e:Ls.we!"eJ!se~L:i,Jl.~oni1,L1J,~~j·(>n_wH.h_t:he.
sonar,the data from the nearby fishwheel was used to
apportion side scan sonar counts.Fishwheels at all
stations have been used to sample adult chinook salmon,but
sampling for this species has been somewhat difficult
because they migrate upriver either at or soon after ice
breakup when the maintenance of sampling gear in the river
is impractical.
The side scan sonar..counts ...recorded at Susitna Station were
not us for defiriirigsusTEiia'-R:iver salIlion .escapeIlients be-
cause of suspected inaccuracy of counts caused by counter
siting problems.Details of these problems are discussed in
ADF&G (1983a).Yentna Station (RM 04)sonar counts were
E-3-2-2
Ii
851021
considered suitable for reporting 1981 and 1982 Yentna River
salmon escapements (ADF&G 1985b).
A tag/recapture program was conducted from 1981 through 1984
to estimate numbers of the five salmon species passing
upstream of Sunshine,Talkeetna and Curry Stations (ADF&G
1985b).In addition,fish were tagged at Flathorn Station
in 1984.Salmon captured at all fishwheel sampling sites
were measured,scales were removed for age determination,
and then,the fish were fitted with tags,color-coded for
each site,and released.Personnel 'surveyed all known and
suspected salmon spawning tributaries (a total number of 15)
and sloughs (34)in the middle river from the confluence of
.the Chulitna and Talkeetna rivers at RM 101.4 to the lower
end of Devil Canyon at RM 148.8 of the Susitna River at
weekly intervals from late July through early October.
Salmon abundance within the entirety of sloughs and selected
tributary index reaches was determined by the above surveys
from 1981 through 1984.The tributary index reaches were
within 0.5 mile (0.8 km)of the confluence with the Susitna
River.In 1984,lower river tributaries were also surveyed
from their confluence with the Susitna River to one-third
mile upstream.All tagged and untagged salmon were counted.
Species population estimates were then calculated from
survey and fishwheel catch data at each station.
The entire lengths of selected tributaries were surveyed for
spawning chinook salmon from helicopters.This was done
from 1981 through 1984 in the Indian River (RM 128.6)and
Portage Creek (RM 148.8).Cheechako Creek (RM 152.5)and an
unnamed creek (RM 156.8)were also surveyed,starting in
1982.Other Susitna,Chulitna,and Talkeetna River drainage
chinook salmon spawning areas were surveyed as part of an
ongoing project since 1975.The purpose of these surveys
was to determine chinook salmon escapement trends in the
Cook Inlet drainage (ADF&G 1985b).The suitability of
helicopter surveys as a census method for chinook salmon is
discussed in Neilson and Geen (1981).
Sockeye,chum,pink and coho salmon spawning activity in
mainstem,side-channel,and tributary confluence locations
of the lower and middle Susitna River was evaluated by a
variety of techniques during 1981 through 1984 including:
observation,electroshocking,and drift gill netting (ADF&G
1985b).Sampling of salmon spawning nests or redds was
performed by egg pumping.This was done after fish spawning
activity terminated.
Adult chinook,chum,and coho salmon were fitted with inter-
nal radio transmitters at Talkeetna and Curry in 1981 and
E-3-2-3
1982.These fish were followed to evaluate directional
movements,upstream migration rates,upstream migration
extent,and spawning locations.
Stationary gill nets were operated near Devil Canyon at
RM 150.2 at five-day intervals from late July to mid-
September 1981 and 1982 to detect adult sockeye,chum,pink,
and coho salmon.
The migratidn timing,upstream migration extent,and pro-
bable spaWning areas of eulachon in the Sus tina River were
evaluated from mid-May through mid-June in 1982 and 1983 by
a variety of techniques.Upstream migration timing was
assessed by stationary gill nets placed at selected Susitna
River estuary locations._The extent of upstream migration
was determined by dip net and electrofishing.Eulachon
spawning habitat was determined directly by searching for
eggs in substrate samples and indirectly by evaluating the
spawning condition of female smelt collected by dip net and
electrofishing at suspected spawning sites.
During 1981 andT982,themigra-tion timing,upstream
migration extent,and spawning habitat selection of Bering
cisco in the SusitnaRiver were investigated.Electro-
fishing was used to assess the upstream migration extent and
spawning habitat selection by cisco,as evidenced by
spawning condition of captured fish.A fishwheel,used for
salmon investigation,was maintained through late September
---1981 an-d -T982-~t-o-ttiter-cep't-cci·s-cco-;-~
(b)Resident and Juvenile Anadromous Fish Investigations (**)
Fish investigations assessed the seasonal distribution and
relative abundance of resident:fish in the impoundment
area (including tributaries and adjacent lakes)and the
middle and lower river.Because few anadromous fish (less
---than-60·adult ..Chinook_salmon.were_observed by_ADF&Gin1.9.84J _
___ar_e_ab_Le_t_o_migka_t.ELllR stream through Devi 1 Canyon Lj uve nil e _
anadromous fish were only studied in areas downstream of the
impoundment zone.Methods for sampling both resident and
juvenile anadromous fish included baited minnow traps,trot
(i.e.,set)lines,hook and line,electrofishing,stationary
and drift gill nets,and beach seines.Studies commenced in
November,·1980 and have continued through spring 1985.
SeleC:tecJ.t:ri.bul::ariesaneJ.-EI'ibUl::aryCoIlffue-nces ,sloughs,
side-channel andmainstem-locationsfromRM10.1 to 148.8 of
t:heS~~it:I1.~Ri,;e~;e~esampled-ciuringthew:i.tlter·(November
to April)and the open-water season (May to October).Fewer
sites were sampleddufingthe winter than during the
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851021 E-3-2-4
Il
851021
open-water season because of sampling constraints,including
the short length of daylight,and ice conditions •.
During the summer field season of 1984,fisheries resources
and aquatic habitat were evaluated within the proposed
access corridor (Plan 18,also referred to as Denali-North)
and that portion of the proposed transmission corridor from
the Watana Dam site to its intersection with the
Anchorage-Fairbanks Intertie (referred to as the Gold
Creek-Watana transmission corridor)(ADF&G 1984a).Forty-
two proposed stream crossing sites and ten lake habitats
were inventoried for fish species.General water quality
(dissolved oxygen,pH,conductivity,and water temperature)
discharge,and substrate data were collected at stream
crossing study sites.
Streams in the corridor were sampled using a backpack
electroshocker.Lakes were sampled using either gill nets,
minnow traps,trot-lines,or hook and line.Otolith or
scale samples were taken at both stream and lake sites for
age/length determinations.
Extensive studies have been performed on the relationships
between habitat and fish in the middle and lower river
(Trihey 1982a;ADF&G 1983k;ADF&G 1984b;ADF&G 1984c;ADF&G
1985c).These studies have focused on examining presence of
spaw~ing activity;access for adult salmon to slough and
tributary spawning sites;and development of relationships
between mainstem flow and fish habitat for spawning,
incubation,and rearing.Methods used have included
instream flow incremental methodology,habitat indices
(ADF&G 1985c)and aerial photographic techniques (R&M
Consultants and EWTA 1985a,b).Habitat characteristics
measured included presence of groundwater upwelling,water
temperature,dissolved oxygen,conductivity,turbidity,
water depth,velocity,substrate and instream cover.In
addition to the above studies,laboratory investigations
were conducted with eggs from Susitna chum and sockeye
salmon to provide a better understanding of the relationship
between temperature and egg incubation (Wangaard and Burger
1983).
Electrofishing was conducted in the lower and middle river
during the 1982-1984 open-water seasons to tag resident fish
and evaluate their seasonal distribution,relative
abundance,and movements within theSusitna River.As part
of this study,individ-ually identifiable radio
transmitters of three-to-six months longevity were
surgically implanted in adult rainbow trout and burbot
during the open water seasons of 1981 through 1984 (ADF&G
E-3-2-5
851021
1985c)at various locations along the Susitna River
downstream from Devil Canyon (RM 152).These tags were used
to evaluate autumn and winter movements and overwintering
locations.conventional winter fish sampling techniques,
under"';ice submerged gill net sets and baited tip-ups,were
used to de~ect non-radio-tagged burbot and rainbow trout.
Juvenile sa1monids outmigrating from the middle river have
been sampled at Talkeetna Station during the open water
seasons from 1982 through 1984.These studies have been
designed to evaluat.e species .and age composition,
distribution,timing of migration,and catch-per-unit
effort.To provide additional informaiton on population
numbers,outmigrant travel times,response to changing
habitat conditions,and·survival,a .mark recapture program
for post-emergent chum and sockeye fry was performed in 1983
and 1984 using half-length coded-wire tags (ADF&G 1985c).
Fish were tagged in various areas upstream of Talkeetna
Station and then recaptured at Talkeetna Station.To
supplement this informaiton,'mark"'recapture by cold branding
juvenile chinook and coho salmon was undertaken in the Devil
Canyon to Talkeetna reach.During 1984,outmigrant traps
were used to sample downstream migrants at Flathorn Station
(RM 20).In addition,intermittent trapping was performed
on the Deshka and Talkeetna Rivers to examine outmigrants.
Studies were conducted upstream from Devil Canyon (RM 152)
to evaluate the seasonal distribution and abundance of
-~~----ArctTc.gray U·ng·'(KDF&G~198:3b~)-.-E-i~ght~ma~jo-r-~G-lear,",water
tributaries,located between RM 173.9 and 226.9,were
sampled monthly from June to September during 1981 and 1982.
Arctic grayling exceeding 8 inches (200 mm)in fork length
were tagged with individually numbered tags.Seasonal
movements and population estimates were derived from fish
recapture data.Segments of the lower one mile of the above
streams were.sampled for Arctic grayling during 1981,
whereas the-entire reache_s.QJlili:lC_Qftheeight streams .that
··-·.---·--....~...-.-.._-_____w_oJJI9.be inundated by the Watana imp;~~dment-were-·sampTed
during 1982.Fish were sampled by baited minnow traps,troe--
lines and seine to detect the presence of other resident
fishes.Selected physical/chemical lotic habitat data were
collected along these tributaries during 1981 and 1982.
~_..1._,,-~:::Threatened and Endangered Species (**)
No th17eate~eclorendangeredspe~ies()f fis~have been.identified
in Alaska.The-USFWS 0982eJ does -not list-any-fish species in
Alaska as being threatened or endangered.The State of Alaska
E-3-2-6
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Endangered Species Act also does not list any fish species as
endangered.
2.1.4 -Overview of Important Species (**)
Fishery resources in the Susitna River comprise a major portion
of the Cook Inlet commercial salmon harvest and provide fishing
opportunities for sport anglers.Anadromous species that form
the base of commercial and non-commercial fisheries include five
species of Pacific salmon:chinook,coho,chum,sockeye,and
pink.
Important resident species found in the Susitna River drainage
include Arctic grayling,rainbow trout,lake trout,burbot and
Dolly Varden.Scientific and common names for all fish species
identified from the Susitna drainage are listed in Table
E.3.2.L
Both eulachon (anadromous)and round whitefish (freshwater)are
present in significant numbers.However,both species receive
little or no interest for either commercial,subsistence,or
sport fisheries.
Salmon utilize the mains tern river environments for migration,
rearing,overwintering,and,to a much lesser extent,spawning.
The majority of the escapement of chinook,sockeye,pink,chum,
and coho salmon in the Susitna drainage spawn in tributaries of
the Susitna River anq do not utilize the mainstem habitats
extensively.
The most important changes due to the project are expected to
occur in the middle river (Talkeetna to Devil Canyon).The
relative importance of middle river mainstem habitats as a travel
corridor to returning salmon adults is indicated by population
estimates made at the ADF&G fishwheel stations at Talkeetna and
Flathorn (Figure E.3.2.5),ADF&G,1985b).In 1984,approximately
6 percent of all coho,12 percent of all chum,2 percent of all
sockeye,10 percent of all chinooks,and 5 percent of all pink
salmon spawning in the entire Susitna drainage basin traveled
through the mainstem middle river to reach their natal grounds.
The remainder of the population spawns in tributaries of the
Susitna River,principally in the Yentna,Talkeetna and Chulitna
River drainages.Adult migration timing varies by species,but
generally the peak inmigration to the middle reach of the Susitna
occurs from late June through September.
Of those salmon that do spawn in the middle river,most spawn in
tributary streams.Based on escapement counts for 1984,34
middle river sloughs,collectively,provided spawning habitat for
851021 E-3-2-7
only approximately 5.5 percent of all salmon migrating above the
Talkeetna fishwheel station (ADF&G 1985b).Coho and chinook in
this reach apparently spawn only in tributary streams,pink
salmon primarily in tributary streams (with a small number
utilizing slough habitats),chum salmon in both tributary and
slough environments,and sockeye almost exclusively in sloughs
(ADF&G 1985b).Despite their relative importance to the
maintenance of both chum and sockeye salmon in the middle river,
slough spawning habitats are not central to the maintenance of
the total Susitna River stocks of either species.Only about 2
percent of all chum and less than 0.5 percent of all sockeye
spawning in the Susitna River in 1984 utilized'sloughs.Spawning
habitat quality apparently varies greatly between sloughs as,in
the last four years,the majority (>88 percent)of the chum
salmon that spawn in slough were found in 10 of the 34 sloughs.
Three of these 10 (8A,11,21)have added significance in that
they also supported over 90 percent of all sockeye spawning in
the middle river.
Relatively few salmon spawn in mainstem non-slough habitats~.Of
those which do,chum salmon predominate.Generally,spawning
habitats within the mainstem proper are small in area and widely
distributed.In 1984,ADF&G made a concerted effort to identify
mainstem middle river spawning habitats,identifying.36 spawning
sites.Numbers of fish counted at each of these sites varied
from one 'to 131 with an average of 35 (ADF&G 1985b).
Four of the five salmon species present use middle river waters
fo:r :rearing purposes (ADF&G-1984cJ.F'romMaytoSeptember
juvenile chinook salmon rear in tributary and side channel
environments,..coho mostly rear ..in tributary and upland sloughs,
and sockeye move from natal side sloughs to upland sloughs for
rearing.From May to July rearing chum salmon are distributed
throughout sl.deslough and tributary st:reamenvi:ronment:s (ADF&G
1984c)•
Rainbow trout and Dolly Varden were recorded at mouths of tribu-
tary streams .-'Ral.nbowtro-tit'do'notC-occtir"upstream from--fjevrr
'-..-----'-~·--Canyon.Arctic grayling are tJie Gominant species upstream from .--------..--
Devil Canyon.
2.1.5 -Contribution to Commercial and Non-Commercial Fishery (**)
(a)Commercial (**)
Figure E.3.2.6i;hows the .ADF&G upper Cook Inlefsa.lmc>n
management areas~.With ·the exception of sockeyeai1.d
chinook salmon,the majority of the upper Cook Inlet
commercial catch of salmon originates in the Susitna Basin
(ADF&G 1984h).The upper Cook Inlet area is that portion of
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851021 E-3-2-8
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851021
Cook Inlet north of Anchor Point and Chinitna Bay (Figure
E.3.2.6).The long-term average annual catch of 3.0 million
fish is worth approximately $18.0 million in 1984 dollars to
the commercial fishery (ADF&G 1984p).In recent years
commercial fishermen have landed record numbers of salmon in '
the upper Cook Inlet fishery with over 6.7 million salmon
caught in 1983 and over 6.2 million fish in 1984.The
quantitative contribution of the Susitna River to the
commercial fishery can only be approximated because of:
o the higher number of intra-drainage spawning and
rearing areas;
o the lack of data on other known and suspected
salmon-producing systems in upper Cook Inlet;
o the lack of stock separation programs (except for
sockeye salmon);and
o overlap in the migration t1m1ng of mixed stocks and :~
species in the Cook Inlet harvest areas.
Therefore,the,estimates of contributions of Susitna River
salmon to the upper Cook Inlet fishery should be viewed as
approximations.
(i)Sockeye Salmon (**)
The most important species in the upper Cook Inlet
commercial fishery is sockeye salmon.In 1984,the
total sockeye harvest of 2.1 million fish was valued
at $13.5 million (ADF&G,1984p).The commercial
sockeye harvest h~s averaged 1.34 million fish
annually in upper Cook Inlet for the last 30 years
(Table E.3.2.2).The estimated contribution of
Susitna River sockeye to the commercial fishery is
between 10 to 30 percent (ADF&G 1985b).This
represents an estimated annual commercial harvest of
between 134,000 to 402,000 Susitna River sockeye over
the last 30 years.In 1983,Susitna River sockeye
contributed approximately 500,000 fish to the total
catch of 5 million (Table E.3.2.3).The 1983
commercial sockeye catch was the highest in 30 years
of record (Table E.3.2.2).
(ii)Chum Salmon (**)
Chum salmon and coho salmon are about equal in
importance in the upper Cook Inlet commercial
E-3-2-9
fishery and rank second and third in value after
sockeye.The upper Cook Inlet chum salmon-catch has
averaged 659,000 fish annually since 1954 (Table
E.3.2.2).The contribution of Susitna River chum to
-the upper Cook Inlet fishery is about 85 percent
(ADF&G 1985b).This contribution represents an
estimated annual chum harvest of 560,000 Susitna
River fish in the commercial harvest over the last 30
years.In 1982,the Susitna River contributed
approximately 1.21 million fish of the record harvest
of 1.43 million chum salmon taken in the upper Cook
Inlet fishery (Table E.3.2.2).In 1984,the total
chum salmon harvest of 684,000 fish in the commercial
fishery was valued at $2.0 million (ADF&G 1984p).
(iii)Coho Salmon (**)
Since 1954,the upper Cook Inlet coho salmon
commercial catch has averaged 264,000 fish annually
(Table E.3.2.2).Approximately 50 percent of the
commercial coho harvest in upper Cook Inlet is from
the Susitna River (ADF&G 1985b).This contribution
represents an average annual Susitna River coho
harvest of 132,000 fish in the commercial fishery
over the last 30 years.In 1982,the Susitna River
contributed an estimated 388,500 fish (Table
E.3.2.3)to a record harvest of 777,000 coho taken by
the upper Cook Inlet fishery.In 1984,the total
-"~oh-os~lm(Yn·lra·rvest-·of-4-4-3-;000-fish in upper Cook
Inlet had a worth of $1.8 million (ADF&G 1984p).
(iv)Pink Salmon (**)
pink salmon is the least valued of the commercial
species in upper Cook Inlet.The upper Cook Inlet
average annual odd-year harvest of pink salmon since
._.._____~954_i s_.abouL120,00.0_..£ish.,with ...a range of..12,500.t0
..._..._.........._....._....._.544,000 fish.The average annual even::year harvest
is approximately 1.58 million pink salmon with a
range of 0.48 to 3.23 million fish (Table
E.3.2.2).The estimated contribution of Susitna
River pink salmon to the upper Cook Inlet pink
fishery is 85 percent (ADF&G 1984h).This
represents an average annual Susi tna Ri v.er
contribution of 0.10 million 6dd';'yearand 1.34
million even-yearp~~I!~:.:_~~1111(')t1.to~l:1el1Pper.Cook Inlet
fishery over the last 30 years.In 1984,the total
pink salmon harvest of 623,000 fish in upper Cook
Inlet was worth an estimated $0.5 million (ADF&G
1984p)•
851021 E-3-2-10
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(v)Chinook Salmon (**)
The commercial chinook harvest has averaged 19,200
fish annually in the upper Cook Inlet fishery over
the last 30 years (Table E.3.2.2).Since 1964,the
opening date of the commercial fishery has been June
25.The Susitna River chinook run begins in late May
and peaks in mid-June.Thus,by June 25 the majority
of chinook have already passed through the area
subject to commercial fishing.Catches of chinook
salmon have averaged 11,600 fish annually for the 20
year period of 1964-1983.Approximately,10 percent
of the total chinook harvest in upper Cook Inlet are
Susitna River fish (ADF&G 1985b).This represents an
average annual contribution of 1,960 chinook to the
upper Cook Inlet fishery for the last 30 years,or
1,160 fish for 1964-1983.In 1984,the-8,800 chinook
caught in the upper Cook Inlet fishery were valued at
$0.3 million (ADF&G 1984p).
(b)Sport Fishing (**)
Increases in population and tourism in Alaska have resulted
in a growing demand for recreational fishing.
Recreational fishing is now considered a significant factor
in total fisheries management,particularly in Cook Inlet
where commercial and non-commercial user conflicts have
developed (Mills 1980).The Susitna River and its major
salmon and resident fish-producing tributary streams provide
a multi-species sport fishery.Estimates of the sport fish
harvest are available for the Susitna River Basin as a whole
and cannot be divided into specific areas which will or will
not be affected by the Project.Since 1978,the drainage
has accounted for an annual average of -127,100 angler days
of sport fishing effort,which is approximately 9 percent of
the 1977-1983 average of 14 million total angler days for
Alaska and 13 percent of the 1977-1983 average of 1.0
million total angler days for Southcentral Alaska (Mills
1979, 1980, 1981, 1982,1983,1984).
The sport fish harvests for 1978 through 1983 from the
Susitna Basin,based on mail surveys to a sample of license
holders,are shown in Table E.3.2.4 (Mills 1979,1980,
1981,1982,1983 and 1984).These are summarized in Table
E.3.2.5.
851021
(i)Arctic Grayling (**)
The annual Arctic grayling sport harvest for the
entire Susitna Basin has averaged 18,200 fish and
E-3-2-11
61,500 fish in Southcerttral Alaska over the last six
years (Table E.3.2.5).The largest sport harvest of
Arctic grayling on record in the Susitna Basin
occurred in 1980 when an estimated 22,100 fish were
caught.This represents about 32 percent of the
total 1980 harvest of Arctic grayling in Southcentral
Alaska (Mills 1981).Due to the rugged terrain and
the remoteness of the impoundment area,it is
believed that few grayling are harvested from this
area.Instead,most grayling are harvested from
areas more accessible by vehicles,boats or airplanes
(e.g.streams along the Parks or Denali Highways).
(ii)Rainbow Trout (*)
The Susitna Basin and Southcentral Alaska annual
rainbow trout sport harvests have averaged 16,000
and 132,900 fish respectiy-ely since 1978 (Table
E.3.2.5).Between 1978 and 1983,an average of about
16,000 rainbow trout were harvested by anglers in the
Susitna Basin,which represented approximately 12
percent of the Southcerttral Alaska rainbow trout
sport catch (Mills 1980).
(iii)Pink Salmon (*)
The annual even-year pink salmon harvest has averaged
42,950 fish in the Susitna Basin and 134,400 fish
-----------------------------ftcSCHftllccE:trtrat-':-A:ta-ska~sincc-e~t978 ~The---annuat-
odd-year pink salmon sport catch has averaged 8,600
fish in the Susitna Basin and 58,300 fish in
Southcentral Alaska since 1979 (Table E.3.2.5).The
-largest sport harvest of pink salmon on record in the
Susitna Basin occurred in 1980 when an estimated
56,600 fish were caught (Mills 1981).
(iv)_CohoSalmon (-,\oJ
Since 1978,the Basin and Southcentral
Alaska annual coho salmon sport harvests have
averaged 13,200 and 103,800 fish respectively (Table
E.3.2.5).
In 1982,about 16,664 coho were landed by anglers in
t.he Susitna Basin (Mills 1983),-wliichis the largest
anIluakcB:tch on record.In 1983,al'mostone of every
five coho entering-thebaS1n-was caught by sport
anglers (Table E.3.2.3).
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851021 E-3-2-12
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(v)
(vi)
Chinook Salmon (*)
The annual chinook salmon sport harvest has averaged
37,300 fish in Southcentral Alaska and 7,950 fish
in the Susitna Basin since 1978 (Table E.3.2.5).
This represents an annual Susitna Basin contribution
of 21 percent to the Southcentral chinook sport
harvest over the six year period.The largest
Susitna Basin sport harvest of chinook salmon on
record occurred in 1983,when 12,420 fish were caught
by fishermen (Mills 1984).
Chum Salmon (*)
The Susitna Basin and Southcentral Alaska annual chum
salmon sport harvests have averaged 6,800 and
12,150 fish respectively since 1978 (Table
E.3.2.5).The largest sport catch of chum salmon on
record in the Susitna Basin occurred in 1978 when
15,700 fish were landed (Mills 1979).For the years
1981 to 1983,chum salmon sport harvests have
averaged between 1.4 and 1.8 percent of the estimated
Susitna Basin chum salmon escapement (Table
E.3.2.5).
(vii)Sockeye Salmon (*)
The annual sockeye salmon sport harvest ha~averaged
112,900 fish in Southcentral Alaska and 2,100 fish
in the Susitna Basin for the years 1978 through 1983
(Table E.3.2.5).In 1983 over 5,500 sockeye salmon
were caught by fishermen in the Susitna Basin,which
is the largest annual sport catch on record (~ills
1984).The sport catch of sockeye from 1981 through
1983 has averaged 3 percent or less of the estimated
Susitna Basin sockeye escapement (Table E.3.2.3).
(c)Subsistence Fishing (*)
The only subsistence fishery on Susitna River fish stocks
that is officially recognized and monitored by the Alaska
Department of Fish and Game is near the village of Tyonek,
approximately 30 miles (50 km)southwest of the Susitna
River mouth.The Tyonek subsistence fishery was reopened in
1980 after being closed for sixteen years.From 1980
through 1983,the annual Tyonek subsistence harvest averaged
2,000 chinook,250 sockeye and 80 coho salmon (ADF&G 1984e).
Although the Tyonek fishery occurs in Cook Inlet,it is
851021 E-3-2-13
suspected that it intercepts fish bound mainly for the
Susitna River.
2.2 -Species Biology and Habitat Utilization in the Susitna River
Drainage (*)
2.4.1 -Species Biology (*)
(a)Salmon (*)
The biology of the five species of Pacific salmon inhabiting
the Susitna River is described in terms of their
freshwater life stages.Specifically,the following
discussion focuses on the upstream migration of the
returning adults,population estimates of the spawning
adults,spawning locations and utilization of spawning
habitats,incubation and emergence of the juveniles,and
juvenile behavior after emergence from the natal areas.
(i)Chinook Salmon (*)
-Upstream Migration of Returning Adults (*)
Chinook salmon enter the Susitna River in late May
and early June soon after the river becomes ice
free.In general,90 percent or more of the
chinook escapement moves past the Susitna Station
(RM 26)and the Flathorn Station (RM 8)prior to
__~-Jul*~L_ea.ch._y-ear.(ADR&GJ983a,198Ah,1985b).Once
the adults move into the river,they begin to
disperse into various tributaries to spawn.
Movement of chinook past the Sunshine Station (RM
80)begins in early June,peaks in mid to late June
and and is essentially complete (more than 90
percent)by early July (ADF&G 1983a,1984h,
1985b).
MovemeiifOfaa.lil EcniiioO'K iiifo Ebemia.aTe--reachOf
---EliE!-Susi-tnaKiver u Beg-ins in-early June;-peaI.<snear--
the end of June and continues to mid-July with 90
percent of the migration past Curry Station
completed by late July (ADF&G 1983a,1984h,1985b,
WCC 1985).The duration of adult chinook
occurrence in the middle Susitna River is depicted
in Figure E.3 •.2 ..7........
Adult chinook that reach Sunshine Station enter one
of the three major upper subbasins of the Susitna
River Drainage:The Chulitna River,the Middle
Susitna River,or the Talkeetna River.Over 90
.]
851021 E-3-2-14 .1
1-1
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851021
percent of the tagged adults observed in the
Chulitna River were caught and tagged on the west
bank at Sunshine Station.Similarly,over 90
percent of the tagged adults observed in the
Talkeetna River were caught and tagged on the east
bank at Sunshine Station.Tagged adults observed
in the middle river (Talkeetna to Devil Canyon)
were caught and tagged on both the east and west
banks in approximately equal proportions (ADF&G
1985b)•
Although adult chinook initially move into one of
the three major subbasins initially,there is
apparently some re-distribution prior to spawning.
It is estimated that up to 45 percent of the adults
moving past the Talkeetna Station (RM 103)and up
to 10 percent moving past the Curry Station (RM
120)return downstream and spawn in either the
Chulitna or Talkeetna Rivers or other tributaries
downstream of RM",100 (ADF&G 1985b).
The rate of movement of adult chinook from the Sun-
shine Station upstream into the middle Susitna
River iSe1.8 to 3.3 miles per day (mpd)from
Sunshine to Talkeetna Station and 2.2 to 4.3 mpd
between the Talkeetna and Curry Stations (ADF&G
1983a,1984h,1985b).
-Population Estimates (*)
An accurate estimate of the total Susitna River
chinook escapement is not available because the
run in the lower river begins either before or
during break-up of the ice cover and it has not
been possible to sample the entire run.The only
monitoring of chinook salmon in the lower river was
conducted at the Sunshine Station where escapements
have been quantified since 1982.Drainage-wide
index counts from tributaries undertaken since 1981
established that most chinook escapement to the
Susitna River occurs to tributaries entering the
Susitna River downstream from the Sunshine Station.
A summary of the estimated escapements upstream of
the Sunshine,Talkeetna and Curry Stations in 1982,
1983,and 1984 is presented in Table E.3.2.6.
Escapement estimates at Sunshine Station have
ranged from 52,900 to 121,700,at Talkeetna from
10,900 to 24,800,and at Curry from 9,700 to 18,000
between 1981 and 1984.
E-3-2-15
Assuming that approximately 10 percent of the
chinook estimated to pass the Curry Station return
downstream to spawn (ADF&G 1985b),the escapement
of adult chinook into the middle river ranges from
8,000 to 15,000 fish annually.
Age Composition (*)
In general,adult chinook salmon return to the
Susitna River to spawn as age 5 and 6 fish with
with considerable variation age composition between
years (ADF&G 1984h,1985b).Each year,some age 3
and 7 fish are also present in the population and
occasionally may constitute a significant portion
of the spawning population (ADF&G 1984h).A
summary of the age composition of fish observed in
1981-1984 at each of the sampling stations is
presented in Table E.3.2.7.
Based on scale analyses of these fishi"',it is
estimated that more than 95 percent of the adult
chinook salmon outmigrated from the Susitna River
as Age 1+juveniles (ADF&G 1985b).
-Spawning Locations and Utilization of Spawning
Habitats (**).
Chinook salmon spawn exclusively in clearwater
"tr·ibutaries-of ..the.$us"itn~iJl:er_._(ADF.&G
1983a,1984h, 1985b,WCC 1985).Index counts of
chinook in tributaries throughout the Susitna basin
have been collected since 1976.A summary of these
counts is presented in Table E.3.2.8 and provides a
general description of the distribution of spawning
areas and their relative importance for chinook
spawning activity.
""·fiiCIfanRiver (rocaEedaTIDfT38~5}"aiidPortage
--.----"-.~._.-._---------~-------.-.--.------~..--..-_.---.-----------·-Creek -(at-RM~-1-40-)--pr-ovia.e-s-pawn:tn-g--h-a·b-i:t-a-t--·f-or-·
nearly all of the chinook salmon migrating into the
middle Susitna Rivers.A summary of peak index
counts for all tributaries of the middle Susitna
River since 1981 is provided in Table E.3.2.9 and
is depicted graphically in Figures E.3.2.8 through
E.3.2.13.-Thesetributary h~bitats will not be
affected llythechanged flow regime attributable to
the"proposed proj ec t .~..
A few chinook,approximately 20 to 45 individuals,
were observed in small tributaries located upstream
]
]
851021 E-3.,..2-16
I I
i I, I
851021
of the rapids in Devil Canyon (ADF&G 1983a,1984h,
1985b).Prior to these observations,velocity
barriers in the rapids were thought to prevent
salmon migration into the upper reaches of the
Susitna.No other species is known to migrate
upstream,through Devil Canyon.
-Incubation and Emergence (**)
Approximately 4,000 to 8,000 pairs of chinook
salmon spawn in tributaries of the middle river.
Spawning occurs in July and early August.Average
fecundity of female chinook has not been estimated
for Susitna River stocks,but Morrow (1980)reports
average fecundities range from 4,200 to 13,600 eggs
per female in Alaska.Incubation begins with egg
deposition in July and ends with emergence of the
fry from the spawning gravels in March or April
(ADF&G 1983m).The incubation period for chinook
salmon is depicted on Figure E.3.2.7.-.",
-Juvenile Behavior (.**)
Chinook emerge from the spawning g:r:avels in
late-March to mid-April.The fry remain near
their natal areas ~in tributaries for one to two
months before initiating a downstr~am movement into
rearing and overwintering areas (ADF&G 1983m,
1984c).The initial downstream movement may result
from territorial behavior by the juveniles.Some
age 0+juveniles move into the mainstem of the
Susitna and have been collected throughout the
drainage basin during the summer.The remainder of
the age 0+juveniles apparently remain in the natal
tributaries'for initial rearing and overwintering
(ADF&G 1983m,1984c).In general approximately 40
percent of the juvenile chinook (all ages)in the
middle river are found in mainstem-associated
habitats from May through November.Approximately
60 percent are found in tributary habitats during
the same period.
The age 0+juveniles that move into the mainstem of
the middle river generally become associated with
areas with moderate water velocity «1.5 ft/sec),
shallow depths «2 ft)and high structural
diversity for cover (ADF&G 1983m,1984c).Where
structural diversity is lacking,the juveniles
apparently use turbid water for cover (ADF&G 1984c,
1985c,EWT&A and WCC,1985).In the lower Susitna
E-3-2-17
River (i.e.downstream of Talkeetna),highest
densities of Age 0+juveniles were collected in
tributary mouth areas characterized by deep,low
velocity,clear water (ADF&G 1985c).
During the initial rearing period,juvenile chinook
feed extensively on chironomid larvae (Insecta:
Diptera)(ADF&G 1983m,1985j).Terrestrial adult
insects obtained from the water surface also
pro~ided a significant portion of the juvenile
chinook diet (ADF&G 1983m,1985j).Growth of age
0+juveniles during the summer months was estimated
from length measurements in 1982 and 1984 (ADF&G
1983m,1985c).In May,age 0+fish average between
40 and 45 mm in length.By Octobe-r.:,average
lengths of age 0+fish range from 60 to 80 mm
(ADF&G 1983m,1985c).Growth rates of·juveniles in
tributaries tend to be greater than those in the
mainstem (Table E.3.2.l0).
Estimatesof thetotal nUIIlber of juvenile chinook
have not been obtained far the middle Susitna
River.However,it was estimated that in 1983,
approximately 10,635,000 eggs were deposited by
adult females in Indian River which provided a
total production of approximately 3,211,000 chinook
fry in 1984.Hence,survival from egg to fry was
approximately 30 percent (ADF&G 1985c).Survival
-~fromilie·fry-stage~"to-·outm:i'grationaskge0+or 1+
fish has not been estimated for chinook.
From September through November,age 0+fish move
into clear water areas such as tributaries,
tributary mouths and side sloughs (wee 1985,ADF&G
1983m,1984c)where they overwinter.The juveniles
apparently grow during the winter and spring since
..··Age ···l+juveni lesaverage ..be tween 85 to 95JIU'Il:i.f!......
....'-"'-'.".'"-'---'."'_...l.engthin_la.t:e_May_(A:O'E.&~1983m)!._Averag~~engths
of outmigratirig Age 1+fish are between 100 and 120
mm at the end of July and early August.
Outmigration patterns of juvenile salmon from the
middle Susitna differ between Age 0+and 1+fish.
.Age 0+juvenileoutmigratiort,as determined from
c>utmig'rant'triippIng'ratesa:f Talkeetna,o~cur at a
xelatiyelyCQJ1StCilt.ltrate.tb.rotJghotJtthesummeJ."with
two peak outmigration periods recorded in 1982 in
late June and early July and mid-August (ADF&G
1984c).In 1983;several peak outmigration events
were observed (ADF&G 1985c).A similar,relatively
.j
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851021 E-3-2-18
.)
j
851021
constant rate of outmigration was observed at the
Flathorn Station in the lower river.Age 1+
juveniles begin to outmigrate from the middle
river in early May.Outmigration of Age 1+fish
from the middle Susitna River is essentially
complete by mid-July (ADF&G 1984b,1985c).
Outmigration from the lower river peaks in mid-June
and is completed by early August (ADF&G 1985c).
It is not clear as to whether the Age 0+outmigrant
juveniles survive once they enter the salt water
environment.Although a large portion of the out-..
migrating juveniles are Age 0+fish,scale analysis
of returning adults indicates that fish outmi-
grating as Age 0+juveniles comprise less than
5 percent of the total escapement (ADF&G 1985b).
The period in which juvenile chinook salmon inhabit
the middle river is depicted in Figure E.3.2.7.In
general,juvenile chinook inhabit the middle river
throughout the year.A single age cohort moves
into the river habitat from the tributaries in June
or July.Some of these migrate downstream to the
lower river while the remainder spend one winter in
clearwater habitats associated with the mainstem.
The following spring,these juveniles·outmigrate to
the lower river and on to Cook Inlet.Outmigration
of this age group from the Devil Canyon to
Talkeetna reach peaks prior to early June and
terminates by the end of July throughout the
drainage.
(ii)Sockeye Salmon (**)
-Upstream Migration of Returning Adults (**)
Sockeye salmon enter the Susitna River system in
two distinct runs (ADF&G 1984h,1985b).The
first run enters the river in late May and early
June.The run passes the Sunshine Station
beginning in early June and is complete by the end
of June (ADF&G 1985b).Although a few first run
fish initially enter the middle Susitna River,all
first run sockeye migrate into the Talkeetna River
and spawn in the inlet to Papa Bear Lake which is
outside the area to be affected by the project.
Second run sockeye enter the Susitna River during
the last half of June.Migration of second run
fish past the Sunshine Station occurs during the
E-3-2-l9
851021
last half of July and the first half of August
(ADF&G 1984h,1985b).Second run sockeye'enter the
middle Susitna River in late July and are present
through August each year.The occurrence of second
run adult sockeye in the middle Susitna is depicted
in Figure E.3.2.7.The escapement to the Flathorn
Station in 1984 was approximately 605,800 fish.Of
these only 3,500 fish were estimated to spawn in
the middle river.This indicates that nearly all
second-run sockeye spawn in tributaries entering
the Susitna at or downstream of the Chulitna River
confluence.
As was the case for chinook salmon,a significant
proportion of the sockeye that initially move into
the middle Susitna return downstream and spawn in
stream-lake systems in the Chulitna and Talkeetna
River,subbasins."In 1984,approximately 35 percent
of the sockeye that reached the Curry Station were
fish·that returned downstream to spawn in other
tributary systems.
Because there are no stream-lake systems associated
with the middle Susitna River,the viability of the
sockeye spawners in the middle Susitna River has
been questioned.Spawning sockeye in the middle
river may be strays from the Talkeetna or Chulitna
Rivers (ADF&G 1983a).Comparison of scales
--collected,-fromc..fishinc-the~-respectivesubbasins did
not provide conclusive evidence that the middle
Susitna population is viable (ADF&G 1983a).
However,the collection of overwintering juveniles
and Age 1+Juveniles can be interpreted as evidence
that the spawners in the middle r1ver do constitute
a viable population (ADF&G 1984c).In addition,
the fact that the number of sockeye using the
middle river for spawning is relatively constant-ancf-Ehat-theyt-ena.---tci-'l:is .e-the-'-sameareaS"-ea-Cll year
may also oe-interpreteaas support for t~-------'
conclusion that the population is viable.These
trends are discussed in more detail below.
The rate of movement of tagged second run sockeye
into the middle river is more rapid than for
chinook ...Adults,-tagged at Sunshine Station,move
b,E!twE!eI12.4 a.,11cl5~_amp.<i,fiQll1 the Sunshine to the
Talkeetna Stations.The average tate ofttavel
from the Talkeetna Station to the Curry Station
ranged from 2.4 to 8.5 mpd ·from 1981 through 1984.
(ADF&G 1981a, 1983a,1984h,and 1985b).Measure-
E-3-2-20
\1
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I.",.,r'
~
,)
j
j
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)
851021
ments of rates of movement were not obtained for
the first run.
-Population Estimates (**)
Estimates of the number of first run sockeye
escaping upstream of the Sunshine Station into
the Talkeetna River were approximately 5,800 fish
in 1982,3,300 fish in 1983 and 4,800 fish in
1984.
Minimum escapements of second run sockeye into the
Susitna Basin range from 175,900 in 1983 to 605,800
in 1984 with an average of 248,400 fish (ADF&G
1981a,1983a,1984h,1985b,WCC 1985).In 1984,
approximately 25 percent of the second run sockeye
in the Susitna Basin migrate into the Yentna
subbasin to spawn.Estimates of the numbers of
second-run sockeye that migrate upstream of the
Sunshine,Talkeetna and Curry Stations are
summarized for the period 1981-1984 in Table
E.3.2.6.In 1984,the second-run sockeye
escapement for these stations were 130,000
(Sunshine Station),13,050 (Talkeetna)and 3,593
(Curry).
Estimates of the total number of sockeye spawning
in the middle river were obtained from periodic
spawning area counts and estimates of stream life
(ADF&G 1984h,1985b).Based upon this analysis,a
total of 2,200 fish spawned in the middle river in
1981,1,500 in 1982,1,600 in 1983 and 2,200 fish
in 1984.Similar comparison with the estimated
escapement past the Talkeetna Station indicates
that up to 95 percent return downstream to spaWn.
-Age Composition (**)
The age structure of the second run sockeye
population is dominated by Age 4 and Age 5 fish.
First run sockeye are predominately Age 5 fish
whereas second run fish are predominately a mix of
Ages 4 and 5.In 1981 and 1982,71 and 73 percent
of the second run fish at Sunshine Station were Age
5 while in 1983 and 1984,64 and 63 percent were
Age 4 (ADF&G 1985b).Some Age 3 and Age 6 adults
are also present but do not represent a significant
portion of the population.
E-3-2-2l
851021
Based upon scale analysis of these fish,it is
estimated that over 90 percent of returning adults
spent at least one winter in freshwater prior to
outmigrating to salt water (ADF&G 1983a,1984h,
1985b).A summary of the age composition of the
sockeye population is presented in Table E.3.2.11.
-Spawning Locations and Utilization of Spawning (**)
Habitat
Nearly all of the sockeye salmon that spawn in the
middle river utilize slough habitats (wee 1985,
EWT&A &wee 1985,HE 1984b,HE 1985a).Estimates
of the number of sockeye spawning in particular
sloughs were obtained for 1981-1984 (ADF&G 1984h,
1985b).Twenty-three sloughs were utilized to
varying degrees.Estimates of the total number of
sockeye in each slough and proportions of_the total
escapements into the middle Susitna for each year
are-summarized in Table E.3.2.12.The locations
and relative abundance,in terms of peak index
counts are presented in Figures E.3.2.8 through
E.3.2.13.Sloughs 8A and 11 provided spawning
habitat for over 80 percent of the slough spawning
sockeye in the middle river in 1984 (1,812 of 2,227
sockeye spawning in sloughs).
Up to 33 sockeye were observed spawning in side
-----channe-l-s -and--ma-i-ns-tem..a-rceas-..Also,as many .as.13
individuals were observed in tributaries.(wee
1985,ADF&G 1985b~.Specific characteristics of
the habitats utilized by the spawning sockeye are
discussed in Section 2.2.2.
-Incubation and Emergence
~,?~kEay~.salmon spawn between the end ofl\.ugust and
the -endofSep-telii;er-CADF&ir1983a-,-1984h,T9850)~...
Based on -the estimatea escapement-orsoc'Keye--t-o-th-e--
middle Susitna River,between 500 and 1,000 pairs
of sockeye spawn.The average fecundity of female
sockeye is approximately 3350 eggs per female
(ADF&G 1984h).Therefore,between 1,500,000 and
3,500,000 eggs are deposited each year.Emergence
of sockeye fry from the-spawning gravels occurs in
March (ADE&G 1983e,1~a3mr.The incubation period
is'depicfediri FigtireE~3~2~7.
E-3-2-22
,f
:\
,).
:~
)
/(
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851021
-Juvenile Behavior (**)
Juvenile sockeye generally rear in lake habitats
and outmigrate as Age 1+or Age 2+fish.
However,in the middle Susitna,suitable lakes are
not available for rearing sockeye.Therefore,
juvenile sockeye either rear in clearwater areas of
the middle river or they migrate to the lower
Susitna River during their first year (ADF&G
1983a,1984c).Based upon results obtained from
outmigrant traps at the Talkeetna Station,a major
portion of Age 0+sockeye evidently move to the
lower river (ADF&G 1984c,1985c).A portion of the
juveniles,however,remain in the middle reach
where they rear and overwinter in side slough and
upland slough areas (ADF&G 1983e,1983m,1984c,
1985c,wee 1985).
Juvenile sockeye salmon feed predominately on
chironom4d larvae,pupae and adults (ADF&G
1983m,1985j).The juvenile sockeye in the middle
Susitna River grow from an average length of 30 mm
in May to 56 mm at the end of August (ADF&G
1985c).
In the lower river,Age 0+juveniles grow from an
average of 36 mm in early June to an average of 60
mm in October (ADF&G 1985c).Age 1+fish grow from
an average length of 71 mm in May to an average
length of 92 mm in July.A summary of lengths of
Age 0+and Age 1+juveniles in provided in Table
E.3.2.13.
It is possible that Age 0+fish that move out of
the middle reach move into side channel,side
slough or tributary mouth areas in the lower
Susitna River where they overwinter.However,
results of outmigrant collections at the F1athorn
Station in 1984 indicate that significant movement
of Age 0+juveniles to the estuary also occurs.
(ADF&G 1985c).Based upon the results of adult
scale analysis,it is likely that most of these
fish do not survive (ADF&G 1985b)(See Table
E.3.2.11).
Outmigration of Age 1+juveniles begins and peaks
in mid May immediately after the river becomes ice
free.Outmigration rates of Age 1+fish then
decrease and the migration is essentially complete
by mid to late June (ADF&G 1985c).The duration of
E-3-2-23
851021
juvenile sockeye occurrence in the middle Susitna
is depicted in Figure E.3.2.7.
(iii)Coho Salmon (**)
-Upstream Migration of Returning Adults (**)
Coho salmon enter the Susitna River begining in
mid-July.The movement of coho past the Susitna
Station peaks in early August and is essentially
complete by late August (ADF&G 1983a,1984h,
1985b,WCC-1985).Coho migrate past the Sunshine
Station begining in mid July with over 90 percent
of the migration past Sunshine by mid to late
August.Coho adults are abundant from the first of
August .to early September in the middle river
(ADF&G 1983a,1984h,1985b).The duration of coho
movement into the middle river is depicted in
Figure E.3.2.7 •.
Although coho initially move into the middle river,
a.majority (75.percentof those migrating past the
Talkeetna Station)return downstream to spawn in
areas below the Talkeetna Station (ADF&G 1984h,
1985b).~p to 45 percent of the coho migrating
past,the Curry.Station return downstream to spawn
(ADF&G 1985b).
__..T.b.e_t:.;;l.te.ofmovem~.!lt of adult.C:l)J'1Q_Jrom~un~l!!.Ile
Station upstream into the middle Susitna River
varies from year to year.The rate of migration
from Sunshine Station to Curry Station averaged 4.0
mpd in 1981,5.3 mpd in 1982,1.4 mpd in 1983 and
2.9 mpd in 1984.Movement rates from the
Talkeetna Station to Curry Station averaged 11.3
mpd in 1981,10 .•0 mpd in 1982,5.7 mpd in 1983 and
2.8 mpd in 1984 (ADF&G.1981a,1983a,1984b,
-Population Estimates (**)
The total estimated escapement of coho into the
Susitna River rang~d from 25,000 to 190,000 fish
annually from 1981-1984 (ADF&G 1981b,1983a,1984h,
1985b).Estimates for 1981,1982 and 1983 minimum
escapements are derived from the sum of the fish
....-estilllatedto-escape Intol:he Yentna 'River and to
Sunshine Station (ADF&G 1984h,WCC 1985).The
estimates do not include numbers of coho that spawn
in tributaries entering the Susitna River between
E-3-:-2-24
)
J
.\
-)
,l
1
i)
\)
851021
the Yentna River and Sunshine Station.A summary
of the estimated escapements for 1981-1984 past the
Sunshine,Talkeetna and Curry Stations is provided
as Table E.3.2.6.
Assumming th~t approximately 75 percent of the
estimated number of coho migrating past the
Talkeetna Station return downstream to spawn,the
total number of coho estimated to spawn in the
middle reach ranges from 500 to 3,000 fish annually
(ADF&G 1984h,1985b).In 1984,the total middle
river escapement accounted for approximately 0.3
percent of the total Susi tna basin escapement-.
These fish spawn almost exclusively in tributaries
which will not be affected by flow or temperature
changes associated with the project.
-Age Composition (**)
The age composition of adult -coho.nindicates two
predominant life histories in the population
that spawns in the Susitna River.The majority of
the spawning population consists of Age 4 fish
which outmigrated from the freshwater environment
during the third year of life (Age 2+juveniles).
The remainder of the adults return to spawn as Age
3 fish which outmigated from the freshwater
environment during their second year of life (Age
1+fish).A few coho adults return to the river as
Age 2 or Age 5 adults (ADF&G 1983a,1984h,1985b).
A summary of the age composition of fish observed
in 1981-1984 at each of the sampling locations is
presented in Table E.3.2.l4.
There are two distinct patterns of juvenile rearing
and outmigration.It is evident that the majority
of the juvenile coho rear for two complete years
prior to outmigrating as Age 2+fish.However,a
significant number of the juvenile coho rear for
only one year and outmigrate as Age 1+fish.
-Spawning Locations and Utilzation of Spawning
Habitat (**)
Coho salmon spawn almost exclusively in tributaries
in the middle Susitina River.A few coho have
been observed in mainstem and slough areas.
However,these individuals were not observed to
spawn (ADF&G 1983a,1984h,1985b).Index counts of
coho in tributaries of the middle reach were made
E-3-2-25
851021
to determine the relative importance of each
tributary for coho spawning.Of 25 streams
surveyed for utilization by spawning coho,only 10
to 12 streams are used to any extent.Coho spawn
primarily in Indian River (RM 138.5)and Whiskers
Creek (RM 101).A summary of the relative
importance of each tributary for coho spawning for
1981-1984 is provided in Table E.3.2.15.Peak
index counts of coho are depicted graphically in
Figures E.3.2.8 through E.3.2.13.These habitats
will not be affected by changes in mainstem
discharge ortempel:'ature regimes assQciated with
the project.Spawning activity occurs between the
first week in September and the first week of
October (Figure E.3.2.7)•.
Incubation and Emergence (**)
Incubation of coho embryos begins in mid September.
Between 250 and 1,500 pairs of coho spawn
annually.Average fecundity is approximately 2,800
eggs par female (ADF&G 1983a,1984h,1985b).
Therefore,between 700,000 and 4,200,000 eggs are
deposited each year.
Emergence of fry from the spawning gravels occurs
between late April and early May (ADF&G
1984c).The incubation pe~iod is depicted in
'Figure ~E;3:2-~T;'--'---',~~.~.~
No estimate of juvenile population size has been
made,therefore,egg-to-fry survival cannot be
estimated.
-Juvenile Behavior (**)
·Af&er-emergencefromthe_spawning_g:J;'J;"Y~ll:),.."ju:y~ni!~
--'--.'coho_ini.tiat_e_a_g~neral downstream movement
within the tributaries.Some of the Age 0+
juveniles move out of their natal tributaries into
the mainstem.The remainder apparently remain in
the tributaries for rearing and overwintering.At
Age 1+,more coho juveniles move out of the
tributaries into the main.stem.Agel+juveniles
a.iso-~·remainhithe·tributaries,overwinter for a
.secondy~al:'ar1<f._g!1~1!1igl:ate as Age 2+fish.(ADF&G
1983n 1984c, 1985c,1983n.)~-
Juvenile coho that m6veinto the mainstem of the
middle reach generally move into clearwater areas
E-3-2-26
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)
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851021
including tributaries,tributary mouths,upland and
side sloughs (ADF&G 1983m,1984c,1985c).'Juvenile
coho prefer low-velocity clearwater areas with high
structural habitat diversity.During the fall,
juvenile coho move into upland and side sloughs to
overwinter.
The average size of Age 0+juvenile coho in the
middle river increased from approximately 40mm in
length to approximately 70mm in length from May
through September (ADF&G 1985c)as measured at the
Talkeetna Station outmigrant trap.In the lower
river,the average length of Age 0+juveniles
increased from approximately 40 mm in June to
approximately 90 mm in late September and early
October (ADF&G 1985c).Age 1+juveniles (1982
Brood year)in the middle river grew from an
average length of approximately 70 mm in June to
over 115 mm in October.In the lower river,the
average length of Age 1+juveniles increased from
approximately 90 mm in May to ,approximately 1l0,mm
in October.(ADF&G 1985c).
Only a few Age 2+juvenile coho (1981 brood year),}
were collected in each sampling period throughout
the 1984 open water season.,Consequently,no
significant increase in length through the summer
was evident (ADF&G 1985c).Incremental increases
in average sizes of juvenile coho during the 1984,
summer collecting season are summarized in Table
E.3.2.l6.
Stomach contents of juvenile coho were examined in
1982 and 1984 (ADF&G 1983m,1985c).Chironomid
larvae were found to numerically dominate the food
items in both studies.
In 1983,outmigration of Age 0+,1+and 2+
juveniles from the middle reach was relatively
constant through the summer.A major peak of
outmigrating Age 0+juveniles in August coincides
w:i.th the redistribution of the fish to
overwintering habitats in the lower river (ADF&G
1984c).In 1984,Age 0+juveniles outmigrated in
early August and Age 1+and 2+fish outmigrated
primarily in June (ADF&G 1985c).
Outmigration of Age 0+juveniles from the lower
river peaked in late August and again in early
October in 1984 (ADF&G 1985c).Peak outmigration
E-3-2-27
851021
of Age 1+and 2+fish occurred in early September
(ADF&G 1985c).
Based upon scale analysis of returning adult coho,
it is likely that the outmigrating Age 0+juveniles
do not survive once they move into salt water.
Juveniles that outmigrate as Age 1+or Age 2+fish
are the largest contributors to the adult
population.
The duration of occurrence of juvenile coho in the
middle Susitna River is depicted in Figure
E.3.2.7
(iv)Chum Salmon (***)
-Upstream Migration of Returning Adults (**)
Adult chum salmon enter the Susitna River basin
beginning in mid July.Adult chum are abundant
in thELlowerriver _~:O:l:il th.e end of August with 90
percent of the escapement passing the Susitna
Station or Flathorn Station during the last two
weeks of August (ADF&G 1981a,1983a,1984h,1985b).
Over 90 percent of the chum which enter the Susitna
River migrate past the Sunshine Station to spawn in
one of the three major subbasins of the Susitna
Drainage:"the Chulitna River,the middle Susitna
River--or the--TalkeetnaRfver (Seeoelow).--
Migration of chum salmon past the Sunshine Station
generally begins in early July and is essentially
complete by the .end of August each year.Peak
movement of chum past the Sunshine Station
generally occurs in the last week of July or the
first week of August (ADF&G 1981b,1983a,1984h,
Initial migration into the middle Susitna (i.e.
past the Talkeetna and Curry Stations)begins
during the last half of July,peaks in early
August and is basically complete by the end of
August (ADF&G 1981b,1983a,""1985b).
Rates of.movement of chum salmon are greater than
rates estimated fot thillook,sockeye and coho.The
average rates of movement upstream from Sunshine to
Talkeetna ranged from 3.3 mpd in 1981 to 5.8 mpd in
1984.From Talkeetna to Curry,average movement
rates ranged from 4.2 mpd in 1981 and 1982 to 8.5
E-3-2-28
}
,1
\!
, 1
I 1
.!
(
I-'
851021
mpd in 1982 and 1984 (ADF&G 1981b,1983a,1984h,
and 1985b).
-Population Estimates (***)
Minimum escapement of chum salmon into the Susitna
River in 1981,1982 and 1983 were 280,000,
460,000 and 275,000 fish,respectively (ADF&G
1981b,1983a,1984h).In 1984,the estimated
escapement of chum salmon to the Susitna River was
813,000 fish based on results obtained from the
Flathorn Station (ADF&G 1985b).
Apparently,more than 90 percent of the chum
escapement migrates past the Sunshine Station.
This is evidenced by the 1984 estimate of 765,000
fish moving upstream of Sunshine compared with the
estimated 813,000 fish migrating past the Flathorn,
Station (ADF&G 1985b).A summary of the estimated
escapement af chum past the Sunshine,Talkeetna and
Curry Stations for 1981-1984 is presented in Table
E.3.2.6.Annual averages for these stations are
431,025 (Sunshine),54,625 (Talkeetna)and 28,225
(Curry)•
Based upon estimated escapements to spawning areas
in the mainstem,side sloughs and tributaries de-
.scribed below,75 percent of the escapement past
the Talkeetna Station and 45 percent of the
escapement past the Curry Station returned
downstream to spawn (ADF&G 1985b).Therefore,it
is estimated that less than 2 percent of the entire
Susitna River chum escapement spawn in habitats
associated with the middle river.
-Age Composition (**)
The majority of the returning adults were Age 4
fish,followed by Ages 3 or 5.(ADF&G
1981b,1983a,1984h,and 1985b).In 1983,Age 5
fish were most abundant.A few return at Age 6.A
summary of the age composition of chums observed in
1981-1984 at each of the sampling stations is
presented in Table E.3.2.l7.
All of the chum salmon returning to spawn in the
Susitna River,outmigrated as Age 0+juveniles
(ADF&G 1981a, 1983a,1984h,1985b).
E-3-2-29
-Spawning Locations and Spawning Habitat
Utilization (*)
Adult chum salmon utilize the widest range of
habitats for spawning of any of the Pacific
salmon using the middle reach.Based on estimated
escapements past each of the sampling stations,
over 95 percent of'the total chum salmon escapement
into the Susitna River spawn in areas upstream of
the Sunshine Station at RM 80 (ADF&G 1985c).
Chum utilize tributary,side slough,side channel
and mainstem areas for spawning within the middle
reach.
Tributaries commonly used by spawning chum salmon
include Indian River,Portage Creek and 4th of July
Creek.Several other streams are used,but to a'
lesser extent.A summary of peak escapement
estimates in tributaries ·of·the~iddle Susitna
River is provided in"Table E.3.2.18 and the peak
ascapements are depicted in Figures E.3.2.8 through
E.3.2.13.Based upon the peak counts,the total
escapement of chum salmon to tributaries was
estimated to be 3,400 fish in 1981,3,500 fish in
1982 (ADF&G 1983a),2,800 fish in 1983 (ADF&G
1984h),and 7,600 fish in 1984 (ADF&G 1985b).
These numbers represent 16.3,7.0,5.5 and 7.7
··~-~-percento~of~he-estimated~oescapements-past·the
Talkeetna Station in each of the respective years
(not accounting for return of adults downstream).
Similarly,these represent 26.7,11~9,13.3 and
15.4 percent of the estimated escapements past the
Curry Station in each of the respective years~
Chum salmon spawned in'nearly every slough within
.........the.middle __S:us.itna ..d:uring.t:h~_19JU::1913.lt~!lJIl!ller~.'
._..~~.....__.__.Peak escal'ements to each slough are depicted in
Figures E.3.2.8 through E.3.2.13.in 1983 an'dT984"-
stream life surveys indicated that the average time
chum salmon inhabit the spawning areas in sloughs
was 6.9 days (ADF&G 1984h,1985b).Using the
average stream life and the total number of
fish-days for chum in each slough,estimates of the
total number of chtJril spawning in the sloughS ware.
calculated (ADF&G 1984h,1985b).Total slough
escapements are summarIZed'for each slough in Table
E.3.2.l9.The total numbers of chum salmon using
slough habitats were 4,500 fish in 1981,5,000 fish
in 1982,2,900 fish in 1983,and 14,600 fish in
r·
851021 E-3-2-30
851021
1984 (ADF&G 1984h,1985b).These estimates
represent 21.6,10.2,5.7 and 14.9 percent of the
escapements past the Talkeetna Station in each of
the sampling years,respectively.Similarly,these
represent 34.3,17.3,13.8 and 29.3 percent of the
estimated escapement past the Curry Station each of
the sampling years.Sloughs 8A,9,11 and 21
support more than 50 percent of middle river slough
spawning chum salmon.
Chum salmon have also been observed to spawn in
side channel and mainstem habitats.In the middle
reach,nine.chum spawning areas were identified to
have spawning in 1982 (ADF&G 1983a),and no
estimate of the total number spawning in those
areas was obtained.In 1983,six sites were
identified to support chum salmon spawning (ADF&G
1984h).Less than 1,000 fish were estimated to
utilize these habitats.In 1984,36 sites were
identified as supporting adult ~hum,spawning.An
estimated total of 3,000 fish used these sites.
The increases in identified use of mainstem sites
for spawning in 1984 was due principally to a more
intensive survey and to the increased escapement to
the middle reach over previous years.In 1984,
mainstem and side channel sites provided spawning
areas for less than 4 percent.of the escapement
past Talkeetna and less than 8 percent of the
escapement past Curry (ADF&G 1985b).
Based on these estimated numbers of chum salmon
observed to spawn in the middle reach,approxi-
mately 75 percent of the escapement past Talkeetna
and 45 percent of the escapement past Curry return
downstream to spawn in areas below RM 98 where the
Chulitna River merges with the Susitna River (ADF&G
1985b)•
Chum salmon spawn almost exclusively in areas
having groundwater upwelling (ADF&G 1983k,
1984b).Although groundwater upwelling is the
principal factor associated with spawning
locations,chum salmon spawning habitat is also
characterized by water depths greater than 0.8 ft.,
water velocities between 0 and 2 ft.per second,
and substrate ranging in size from large gravel to
cobble (ADF&G 1984b).The sizes of substrate used
by chum salmon are large in comparison with
substrate sizes utilized elsewhere in Alaska (Hale
1981b,Wilson et aI,1981).This is probably due
E-3-2-3l
851021
to the dependence of chums on upwelling areas and
overestimation of the predominant substrate sizes
by the investigators (ADF&G 1984b).
Spawning by adult chum occurs between the middle of
August and the end of September in all areas (ADF&G
1983a,1984h,1985b).This period is depicted in
Figure E.3.2.7.
-Incubation and Emergence (**)
Incubatibn of the chum embryos begin with
deposition of the eggs in mid August to late
September (Figure E.3.2.7).
Emergence of the fry from the spawning substrate
occurs in February and March (ADF&G 1983m,1984c,
1985c)•
Based upon the estimated number of spawning chum
salmon in the middle reach,between 3,000 and"
13,000 pairs of chum salmon spawn in areas
associated within the middle reach.The fecundity
of chum salmon is approximately 3,200 eggs per
female.Therefore,between 9,600,000 and
41,600,000 eggs are deposited ea:ch year.Egg to
fry survival is estimated to be 12 to ,14 percent
(ADF&G 1984c,).
-Juvenile Behavior (**)
After emerging from the spawning gravels,juvenile
chum salmon remain near the natal areas until
earlytotllid-May.,,'They then begin a general
downstream movement out of the middle Susitna
River.All juvenile chumoutmigrate from the
ll1ic.i<:ile dY~:J:1:lY'~h.~~!1,<:1Q~"-I:tllY{'\I>f&G 1983m
1984c,1985c).In the intervening period,
--"""':::j:':::u"':v:"":e'-=niles increase in average si-zerrom aTemgth of
40 mm in May to 48 mm in July (ADF&G 1985c).
Outmigration from the lower Susitna River into Cook
Inlet similarly occurs between late May and mid-
July (ADF&G 1985c).Peak outmigration of juvenile
c,h'UlIl occlirS iIl.lIlid-:Jl.l11~"forboth the middle and
lower reaches •(ADF&G 1985c).
No additional growth increment was observed for
chum salmon between the Talkeetna Station
E-3-2-32
J
,.1.'\
J
/,1
--J
j
851021
outmigrant trap and the Flathorn outmigrant trap in
1984 (ADF&G 1985c).
The outmigration period for chum salmon is depicted
in Figure E.3.2.7.
(v)Pink (**)
-Upstream Migration of Returning Adults (**)
Pink salmon enter the Susitna River in late June to
early July.Movement of the adults upstream is
rapid with the movement of fish past the Sunshine
Station beginning in early July and ending in mid
August (ADF&G 1983a,1984h,1985b).Movement of
pink salmon into the middle reach begins in
mid-July and is complete by mid-August,as
determined from the movement past the Talkeetna
Station.Essentially all of these fish spawn in
tributaries upstream from the influence of mainstem
discharges and will not be affected by the proposed
project.
As with the other salmon species,the movement of
pink salmon into the middle river does not indicate
where they will spawn.Up to 85 percent of the
pink that migrate past the Talkeetna Station and up
to 80 percent migrating Past the Curry Station
return downstream to spawn elsewhere in the river
system (ADF&G 1985b).
The rates of upstream movement of pink salmon
ranged from 2.6 to 7.7 mpd from the Sunshine
Station to the Talkeetna Station and from 5.7 to
17.0 mpd from Talkeetna to Curry (ADF&G 1985b).
The migation period is depicted in Figure
E.3.2.7.
-Age Composition (**)
Two distinct stocks of pink salmon use the Susitna
River to spawn.All pink salmon follow a two
year life history and return to spawn as Age 2
fish.The two stocks are distinguished as
even-year fish (those which spawn in even-numbered
years)and odd-year fish.As discussed below,the
even-year stock is numerically dominant in the
Susi tna River.
E-3-2-33
-Population Estimates (**)
The numerical dominance of the even-year pink stock
is evidenced by the estimated escapement to the
Susitna River.Minimum escapement of adult pink
salmon in 1982,based on the sum of the Sunshine
Station and Yentna escapements was 890,500 fish
(ADF&G 1983a).In 1984,the escapement past the
Flathorn Station was estimated to be 3,629,900 fish
(ADF&G 1985b).Estimates of the minimum
escapements in 1981 and 1983 were 85,600 and
101,200 fish,respectively (sum of Sunshine and
Yentna Station escapements)(ADF&G 1981a,1984h).
Estimated escapement of pink salmon upstream of the
Talkeetna Station was 73,000 and 177,900 in 1982
and 1984,respectively.In 1981 and 1983,the
estimated escapements past Talkeetna Station were
2,300 and 9,500 fish,respectively.Escapement
estimates for all sampling stations are summarized
in Table E.3.2~6.Based on 1984 results,less than
one percent of the totalSusitna Basin pink salmon
escapement spawned in habitats associated with the
middle river.
-Spawning Locations and Utilization of Spawning
Habitats (**)
~~·-·-"More "than~90""percent~~()f-~the~pi·nk-sa.lmon-in.the.
middle reach spawn in tributaries that are not
affected by mainstem discharges and,therefore,
will not be affe<::ted by the project.A summary of
peak index counts of pink salmon in the tributaries
is presented as Table E.3.2.20 for the four year
sampling period.The distribution of spawning
locations is depicted on Figures E.3.2.8 through
r
.1
A small portion of.the pink··saTmon"spawnTil"S!ough _.'.'.'-'"
habitats.Even-year pink salmon tend to spawn in '1
sloughs more than 6dd-yearpink salmon.Whether \
this difference is due to stock differences or
density differences is not known.Peak counts in
slough areas are depicted in Figures E.3.2.8 I I
.........tb.r6ugh:E~.3.2 ;13;;
'spawningac::EiviEy'oCciirs duriIlgAugliSt and
occasionally during the first week of September
(See Figure E.3.2.7).
851021 E-3-2-34 :01
,r
-Incubation and Emergence (**)
Incubation of pink salmon embryos begins with
deposition of the eggs in August.Emergence of
the fry probably occurs in March and April.
In odd years,100 to 600 pairs of pink salmon spawn
in the middle reach based upon the estimated
escapement and the estimated return downstream
(ADF&G 1985b).In even years between 5,000 and
12,000 pair of pink salmon spawn in the middle
reach.The estimated fecundity of pink salmon is
1,500 eggs per female (ADF&G 1984h).Therefore,in
odd years between 150,000 and 900,000 eggs are
deposited.In even years,between 7,500,000 and
18,000,000 eggs are deposited.No estimate of egg
to fry survival of pink salmon in the Susitna River
is available.
-Juvenile Behavior (**)
After emergence from the spawning gravels,juvenile
pink salmon move out of the tributaries and the
middle reach almost immediately with no increase in
size.Peak outmigration of pink juveniles occurs
by mid June (ADF&G 1985c),and is complete by mid
July.
(b)Other Anadromous Species (0)
(i)Bering Cisco (0)
The Bering cisco is a coregonid (whitefish)that
occurs from the Beaufort Sea to Cook Inlet.
Although Bering cisco have been collected from upper
Cook Inlet and the Knik Arm,the species was not
known to inhabit the Susitna River drainage prior to
1980-1981 ADF&G studies.Interior and western
Alaskan populations appear to contain both anadromous
and freshwater resident forms.Susitna River Bering
cisco appear to be anadromous (ADF&G 1981a).
Bering cisco were collected in the lower Susitna
River between RM 70 and RM 98.5 in 1981 and 1982
(ADF&G 1983a).In 1981,the migration began in
August at Susitna Station (RM 26)and on September 8
at Sunshine Station (RM 80).The 1981 fishwheel
catches peaked on September 21 at Sunshine.In 1982,
the migration began on August 7 at Susitna Station
851021 E-3-2-35
and on September 4 at Sunshine Station.The 1982
fishwheel catches peaked on September 27 •.
During 1981,spawning concentrations were identified
at RM 78-79,76-77.5 and 75.In 1982,spawning was
confirmed at RM 76.8-77.6 and 81.2 (ADF&G
1983a).It is suspected that spawning may occur
throughout the reach between RM 30 and RM 100 (ADF&G
1981e).Spawning substrates were composed primarily
of 1-to 3-inch (2.5-to 7.5-cm)gravel.Peak
spawning occurred during the second week of October
in both 1981 and 1982 (ADF&G 1983).Susitna River
Bering cisco appear to occupy their spawning grounds
15 to 20 days.After spawning,these fish migrate
downstream to sea (ADF&G 1981a).No spawning areas
for the Bering Cisco are known to exist in the middle
river.
(ii)Eulachon (0)
The eulachon is an anadromous member of the smelt
family that spends most of its'life in the marine
environment.-Adults are believed to live at moderate
ocean depths in the vicinity of the echo-scattering
layer and in clos~proximity to shore.In the north-
ern portion of its range,eulachon spawn in May and
June.
During 1982,-the-spawni·ng-mi~grat·ion·appeared·tobe
composed of two segments:an early run that started
prior to May 16 and en4ed about May 31,'and a late
run that started about June 1 and ended about June 10
(ADF&G 1983a).The second run was approximately 4.5
times larger in'numbers than the first run.Eulachon
are known to utilize the Susitna River system at
least as far upstream as RM 58 in 1981 and RM 48 in
J9§2 C~:PF&GJ98~~}.
""--"--..~--_._---------_._--_._-_.-I-n~--'-r982-,--e-uI-~chon _·s·pawned -'-In'r':[f f1"e-a reas--'-a-nd-'---o-f-f-~--.._,_~_-_.,-----_._--
shore of cut banks on unconsolidated sands and gra-
vels.Spawning occurred at water temperatures be-
tween 37.4 to 49.1°F (3.0 to 9.5°C)(ADF&G 1983a).
(c)Resident Species (***)
(i)Dolly Varden Char (***)
Dolly Varden are found in lakes,streams,and
rivers throughout Alaska.Three forms of Dolly
,1
·rI
'.\
j
'J
'I
851021 E-3-2-36
I 1
851021
Varden have been identified:an anadromous form that
generally inhabits coastal streams,a resident
variety that inhabits rivers and lakes,and a dwarf
resident form that occupies stream and lake habitats
generally north of the Alaska Mountain Range (Morrow
1980).
Within the Susitna River drainge,Dolly Varden are
known to inhabit various areas from the Oshetna River
(RM 233.4)to Cook Inlet (ADF&G 1981f,1981e,1983m,
1983b,1984c,1985c).Throughout the drainage,
populations are relatively low with insufficient
numbers of fish caught to determine population size
estimates.In the lower river (downstream from the
Chulitna River confluence at RM 98.6)Dolly Varden
were most commonly caught at the mouth of the
Kashwitna River (ADF&G 1983m,1985c).Within the
middle Susitna River,Dolly Varden were captured most
frequently at the mouths of Indian River (RM 138.6),
Lane Creek (RM 113.6)and Portage Creek (RM 148.8).
Based on the data available for Dolly Varden
populations in the middle and lower Susitna River
(downstream from RM 150)it is presumed that Dolly
Varden move into the tributaries during the summer
months to rear and feed.In the fall,the Dolly
Varden move into the mainstem in November and
December to overwinter (ADF&G 1983m).Apparently,
juvenile Dolly Varden move into the tributaries in
the spring for rearing.Sexual maturity is attained
at approximately Age 4.(ADF&G 1983m,1984c).
Between the Oshetna River and Devil Canyon (i.e.,in
the impoundment zone)Dolly Varden populations are
apparently small but are widely distributed (ADF&G
1983b).Populations have been found in Cheechako,
Devil,Watana,Jay and upper Deadman Creeks (ADF&G
1983b).Total lengths of the fish collected in the
upper Susitna River ranged from 120 to 205 mm.Thus,
these stocks appear to be representative of the
stunted or dwarf variety noted by Morrow (1980).
This occurrence appears to be inconsistent with the
distribution of the dwarf variety described by Morrow
(1980).However,Morrow's description is based on
the limited information available prior to the
present studies and these could represent a more
refined definition of the range of the dwarf variety
and is therefore,not unexpected.
E-3-2-37
851021
Seasonal movements of the population in the
impoundment zones appear similar to those described
for the middle and lower reaches of the Susitna
River.
Populations of Dolly Varden were identified in
numerous streams and lakes within the access and
transmission line corridors (ADF&G 1984a).
Summaries of the occurrence of Dolly Varden in the
streams and lakes are presented in Tables
E.3.2.21 and E.3.2.22,respectively.The locations
of the streams and lakes are depicted in Figures
E.3.2.8 through E.3.2.13 and Figures E.3.2.14 through
E.3.2.17.
(ii)Rainbow Trout (***)
Rainbow trout inhabiting the Susitna River constitute
one of the northernmost populations of this species
(Morrow 1980).Within the Susitna River,rainbow
trout populations are found up to and including
Portage Creek at RM 148.8 (ADF&G1983m).No
populations have been identified upstream of Devil
Canyon in the impoundment zone.
During the spring and summer months,rainbow trout
are distributed in clear water areas associated with
tributaries and tributary mouths (ADF&G 1984c).
-Highest·concentcrations~,of.rainbow_trout_hav:.e .b,een
observed associated with the Deshka River in the
lower Susitna River (ADF&G 1985c)and Whiskers Creek,
Chase Creek,and Fourth of July Creek in the middle
Susitna River (ADF&G 1984c).Rainbow trout often
follow salmon to their spawning areas in tributaries
and side sloughs where they presumably feed on eggs
dislodged from the salmon redds.During the summer
period,highest densities of rainbow trout are"observedups treamlo'EhefriDiiE-a:ri es~C-'BY··.
~-.----~-_.-._~----_.-mfa--Septemoer;ra-iIiliow --troiit-move-·-to-t-t"i-b-utary--mou"t-h-
areas and presumbly move into the mainstem to
overwinter.
Spawning activity probably occurs in late May to
early June in upper reaches of tributaries.This is
'..based upon the inability'to capture juvenile rainbow
trout at locations associated with the mainstem in
'early to midsummer.Juveniles are collected more
frequently in the lower portions of tributaries as
winter approaches (ADF&G 1984c,1985c).Fourth of
July Creek appears to support a significant spawning
E-3-2-38
1.'J
.\
·1
851021
population.The ADF&G (1985c)believes that rainbow
trout are produced in lakes in the Fourth of "July
Creek drainage.These move out into the river and
rear.Growth of juvenile rainbow trout is similar to
other northern populations (ADF&G 1983n,1981e,
1983m)•
Juvenile and adult populations in the middle Susitna
River are relatively small.Estimates of the
population range from 2,500 to 5,000 fish (ADF&G
1984c).The major contributor to the low population
levels is attributed to the lack of suitable spawning
areas (ADF&G 1984c).In addition,survival rates are
relatively low.High mortality rates are attributed
to poor spawning habitat,and low survival of
juveniles and adults during winter months.In
addition,fishing pressure during the fall,when this
species is particularly vulnerable to capture at
tributary mouth locations,contributes to the low
population levels.Winter mo~tality is due
principally to dessication and freezing (ADF&G 1984c,
1983e,1985a).Several instances of dead
radio-tagged fish have been recorded under the ice
(ADF&G 1983e,1985a).
Habitats suitable for rainbow trout include clear
water areas with velocities less than 0.5 ft per
second and depths greater than 2 ft.Rainbow trout
are also associated with areas containing
cover in the form of undercut banks,debris and
substrate greater than 3 inches diameter (preferrably
boulders)(ADF&G 1984c).
Movement of rainbow trout during summer and winter
months has been documented through tracking of
radio-tagged fish.Based on the results of the
tracking,rainbow trout apparently move freely from
tributary to tributary during the summer and
throughout the mainstem areas during the winter
(ADF&G 1981 e,1983m,1983e,1984c,1985a).I n the
summer,the mainstem areas apparently serve
principally as a migratory pathway;whereas,in the
winter,the mainstem serves as holding areas (ADF&G
1985c,1983m).
A population of rainbow trout was also identified in
High Lake,near High Lake Lodge.High Lake is within
the access and transmission line corridor between the
Watana and Devil Canyon Dam sites.No estimate of
the population size was made.(ADF&G 1984a).
E-3-2-39
851021
(iii)Arctic Grayling (*)
The Arctic grayling is also one of the most important
sport fish of Alaska and northern Canada and
contributes substantially to the sport fishery of the
Susitna River and its tributaries.Grayling are
generally residents of clear,cold streams and lakes
(Scott and Crossman 1973).
Silt-laden glacial systems,such as the Susitna
River,are believed to support relatively few gray-
ling;however,such systems may provide essential
migratory channels and over-wintering habitat (ADF&G
1981f).The Arctic grayling is characterized by Reed
(1964)as a migratory species.During spring breakup
from April to June,adults migrate from ice-covered
lakes and large rLvers into clear,gravel bottomed
tributaries to spawn (Morrow 1980).In Alaska,
Arctic grayling reach sexual maturity at age 2 to 7
years and are capable of spawning several times ''''.
during their lifetime.After spawning~the adults
move from the spawning a.reas"to spend the rest of the
summer feeding on aquatic and terrestrial insects
taken from the aquatic drift (Vascotto 197.0).A
downstream migration to overwintering areas i~large
rivers and deep lakes occurs in late August to
mid-September (Pearse 1974)•
.'~~-~Du·r-ing·c1980-81~g't'acy-l"ing-werce ·capt-urced between
Al.exander Creek (RM 10.1)and the upper reaches of
the impoundment area.Catches were low throughout
winter,but increased sharply in May,both below and
above the impoundment area.Below the impoundment
area,catches increased during the period May 1-15
and then declined at all habitat locations throughout
the summer,until catches again increased at tributary
mouths in Sept~mbeI""Primarytributar~E!s of~he
-tilidciTe-river whichsupp·ort··gra yiIng ·popuIa t:i.Ons·are·
.....__...Indian R[ver~··and Portage CreeklADF>9-8".3mr.-WfffiTii
the impoundment area,catches were highest in June
and July and declined toward the end of summer and
early fall (Table E.3.2.23).
Changes in distribution and catch of grayling are
associated with migrational movements to spawning
~groundsand.overwinteringareas.that may have been
iriifiatedinre·sponse tostirface'water temperat·tire
(ADF&G 1981f,1983b).Below the impoundment area,
high catches in May are associated with migration
E-3-2-40
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851021
from the mainstem Susitna into nonglacial tributary
spawning grounds immediately after ice leaves the
tributaries (ADF&G 1983b).High catches in September
are probably associated with migrational movements
back to over wintering areas in the mainstem
Susitna.
Within the impoundment area in May and June,grayling
appeared to move upstream into pool-type habitat in
tributaries where they spawn.The movement may be
triggered by increasing water temperatures (ADF&G
1981f,1983b).As surface water temperatures began
to decrease in late summer and early fall,lower
numbers of fish w~re observed in these upper stream
reaches and tagged fish were observed migrating
downstream.Small-scale distribution patterns and
abundance within upper stream reaches are determined
primarily by streamflow and channel morphology.
Observed preferred grayling habitat is characterized .~
by high pool/riffle ratios,large,deep pools:,and
moderate velocities (ADF&G 1983m,-1983b,1984c).
Additional distribution patterns in the impoundm~nt
reach were documented by catching,tagging and re-
leasing 2,511 grayling during.1981 (ADF&G 1981f).
Many tributary fish moved into the Susitna mains~em
for overwintering.Analysis indicates that there is
a wide range of intertributary migration as well as
movement within individual tributaries.
Grayling population estimates were calculated for the
reaches of major tributaries to be inundated by the
Devil Canyon and Watana impoundments (Table
E.3.2.24).The 1982 estimates were based on
tag/recapture data during July and August 1982,while
the 1981 estimates were based on results from the
entire summer period.There were insufficient tag
returns from Watana Creek in 1981 and from Tsusena
and Fog creeks in 1982 to derive estimates.The 1982
population estimate was calculated for age groups
(Table E.3.2.25).The total grayling population in
the impoundment zone was estimated to be at least
16,000 in 1982,while the population of grayling over
8 inches (20 em)was estimated to be 9,375,excluding
Watana Creek in 1981 (ADF&G 1981f,1983b).In 1982,
summer density estimates ranged from 323 grayling per
mile (1.6 km)in Watana Creek to 1,835 grayling per
mile (1.6 km)in Deadman Creek for the reaches to be
inundated (Table E.3.2.24).
E-3-2-41
851021
There was no evidence of grayling spawning at any
sampling locations between Devil Canyon ana Cook
Inlet.It is thought that adult grayling from the
mainstem Susitna below Devil Canyon migrate into
nonglacial tributaries to spawn in late April or May.
In the impoundment reach,grayling fry were captured
at the Watana Creek study area in 1981 indicating
spawning in the immediate vicinity.
Spawning apparently occurs from late April through
early May under ice or during mid-May spring floods
in the lower reaches of all eight tributaries sampled
within the impoundment zone (ADF&G 1983b).Suitable
spawning habitat,i.e.,proper spawning gravel in
pool regions,was observed in all streams studied
(ADF&G 1983b).Assuming favorable spawning
conditions exist,it is not likely that-spawning
habitat significantly limits grayling in the
impoundment area (ADF&G 1983b).
In addition to the tributary population,Arctic
grayling populations were identified in Sally Lake,
Deadman Lake and an unnamed lake on the south bank of
the Susitna River near the mouth of Watana Creek.The
population identified in Deadman Creek is associated
with upper D~adman Creek.The lake apparently
provides overwintering habitat for the population in
the creek (ADF&G 1984a).The population found in
.··Sally-:&ake~appears··t;o~be-·stunt;ed~·wit-hadul-t-gI'ayling·
remaining much smaller than the adults associated
with tributaries of the Susitna River (ADF&G
1983b).
Arctic grayling populations were also identified in
seven streams that will be crossed by either the
access road or the transmission line between the dam
13.!.t ~13.a.1l.~L _G()J.~__Gl:'~~!t (A:Pl?&g!~~4~J_.'A l:l,l!~~~l:'y(?f the
streams containing Arctic grayling populations is
'-presented--·-as~TabIe ~302.2T:-----Mai>s···-depi c ti-ng the ..-..--------_.-
access road and transmission line corridors and
enumerating the streams to be crossed are presented
as Figure E.3.2.8 through E.3.2.13.Two lakes within
the access road and transmission line corridor
contain Arctic grayling populations.These are
n-eadfilatl··I;ake(desc-ri bed -above)and Beaver Lake.The
locations of alL lakes within the corridors are
-de'pieted in Figureslr~3.2'.14 throughE.3.2.17.The
occurrence of grayling in these lakes is summarized
in Table E.3.2.22 ..
E-3-2-42
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851021
(iv)Lake Trout (***)
Near the Watana impoundment area,lake trout were
collected in Sally Lake in the impoundment zone and
Deadman Lake.Both lakes support a limited sport
fishery.The population inhabiting Sally Lake is
small,estimated at approximately 1,000 fish (ADF&G
1983b).The population of lake trout in Deadman Lake
is somewhat larger.Numerous lake trout were
observed in Deadman Lake in relatively shallow water
near the inlet stream (ADF&G 1984a).
In both Sally Lake and Deadman Lake,lake trout were
located in relatively shallow water in June.Later
in the summer,the fish were in deeper water,up to
75 ft deep,just below the thermocline (ADF&G
1984a).In October and November,the lake trout
again moved to shallow water along the shorelines,
apparently to spawn.
Ages of four lake trout in Deadman Lake ranged from
15 to 26 years (ADF&G 1984a).
(v)Burbot (**)
In Alaska,burbot are distributed in the Susitna
and Copper Rivers,Bristol Bay drainages,
throughout the interior,and in the Arctic (McLean
and Delaney 1978).Burbot mature between ages 3 and
6 in Alaska and may live a total of 15 to 20 years.
Burbot are widely distributed throughout the
mainstem Susitna River.Adults are found at
tributary and slough mouths and in turbid mainstem
areas.Burbot are typically sedentary but may move
considerable distances during the fall prior to
spawning in the winter (ADF&G 1983b).
Burbot appear to be more abundant in the lower river
from the Chulitna River confluence to Cook Inlet
(ADF&G 1985c).In the middle river,population
densites were estimated to be 15 fish per mile (ADF&G
1984c).
In the Susitna River,spawning occurs from November
to February (ADF&G 1981e,1983m).Although no
spawning activity was observed,the increase in
density of adult fish at the mouth of the Deshka
River and the migration of radio-tagged adult fish to
the mouth of the Deshka River indicated a high
E-3-2-43
851021
probability that spawning occurs in the area (ADF&G
1985b)•
Adult burbot apparently prefer areas with low light
conditions (Morrow 1980),thus,the turbid mainstem
areas provide the most suitable habitat.Burbot have
been as characterized is being omnivorous carnivores
(Morrow 1980)and are believed to be a major fish
predator on other Susitna River fish species (ADF&G
1984c)•
In addition to the burbot populations identified in
the mainstem of the Susitna River;Beaver Lake,
located along the access corridor,contains a
population of burbot (ADF&G 1984a)(Figure
E.3.2.15).
(vi)Round Whitefish (**)
Round whitefish are distributed across all of Arctic
and interior Alaska.They are normally abundant
in clearwater streams with gravel-cobble substrate
but are also in large glacial rivers and lakes.
Round whitefish mature between ages 4 to 7,and
spawning occurs in late September through October
over gravel substrate in t~e shallows of rivers and
inshore areas of lakes (Morrow 1980).Upstream
migrations are often associated with spawning.
The densities of round whitefish tend to be greatest
in the middle river between Devil Canyon and
Talkeetna (ADF&G 1983m).Adult round whitefish move
into clearwater tributaries in June to rear.In
September,round whitefish move into the mainstem
where they spawn and overwinter.Spawning adults
have been ~ollected from the mouths of Lane Creek,
Indian~iver,and I?ortage Creek in October (ADF&G19SSe).---..----.--------------------
Round whitefish appear to be the most abundant
resident fish species downstream from Devil
Canyon;in the impoundment zone,round whitefish are
relatively uncommon (ADF&G 1983b).
Round whitefish-are also-reported to inhabit Deadman
Lake where they apparently serve as a forage fish for
Arctic graylirig(ADF&G 1984a)~Dliri fig the sliilIlIleI'
months,the fish occurred in small schools of 10 to
25 fish.In the fall,schools of 50 to 100 fish were
E-3-2-44
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(vii)
observed to spawn in 1-5 ft of water over sand and
gravel substrate (ADF&G 1984a).
Humpback Whitefish (**)
In Alaska,there is a complex of three closely
related species of whitefish:humpback whitefish,
Alaska whitefish,and lake whitefish.Because of
similar appearance and overlapping distributions,the
data collected on the three species have been
reported under the general heading of humpback white-
fish.
Alaska whitefish are largely stream inhabitants and
undertake lengthy up-and downstream migrations to
and from spawning grounds.Spawning occurs in
September and October.Lake whitefish reside pri-
marily in lakes but spawn in rivers or creeks between
October and December.Humpback whitefish is appar-
ently the only species of whitefish that is
considered anadromous,although migration habits vary
widely in different systems.Spawning migrations
begin in June with spawning in October and November
(Morrow 1980).
Humpback whitefish are most abundant in the Talkeetna
to Cook Inlet reach.Fish collected ranged from ages
2 to 7;Age 4 was the predominant age group (ADF&G
1981f,1983m).
No evidence of humpback whitefish spawning was
collected at any sampling location between Devil
Canyon and Cook Inlet in 1981 or in 1983 (ADF&G
1981e,1984c).
In 1983,humpback whitefish were collected from
Deadman Lake (ADF&G 1984a).No estimate of the
population was obtained.The youngest fish analyzed
was 8 years old and all fish longer than 345 mm were
10 years old or more (ADF&G 1984a).
851021
(viii)Longnose Sucker (**)
The longnose sucker,the only representative of the
sucker family found in Alaska,is ubiquitous and
occurs in most of the mainland drainages.Spawning
usually occurs in spring after ice out.Spawning
runs (i.e.,movement from lakes into inlet streams or
from deep pools into shallower,gravel-bottomed
stream areas)are initiated when water temperatures
E-3-2-45
851021
exceed 5°C (41°F).Longnose sucker feed almost
exclusively on benthic invertebrates but will
occasionally ingest live or dead fish eggs (Scott and
Crossman 1973).
Longnose suckers were collected throughout the study
area from Cook Inlet to the upper reaches of the
impoundment areas.Adult suckers were captured in
the impoundment zone from May to September,generally
near the confluence of mainstem river and the
tributary streams (ADF&G 1981f,1983b).
Downstream of Devil Canyon,longnose suckers are
considerably more abundant than upstream from Devil
Canyon (ADF&G 1983m).Spawning occurs in late May
and early June •.During this period,adults
congregate in spawning areas.During the remainder
of the year,adults are more dispersed throughout the
mainstem (ADF&G 1983b,1985c).Juveniles appear to
utilize clearwate·r sloughs and tributary mouth
habitats to a greater extent than adults (ADF&G
~1983b)•
(ix)Threespine Stickleback (**)
Threespine stickleback have been observed and
captured at several locations throughout ~he Devil
Canyon to Cook Inlet reach of the Susitna River.
They are found most often in shallow,slack-water
areaswithsoftsand-to-mud-subst-rcate and.emer.gent or
submerged,rooted vegetation (ADF&G 1984c,1985c).
These areas are essentially limited to side-slough,
upland slough,tributary mouth and tributary
habitats.
Two forms of the threes pine stickleback,
distinguished by behavior~land morphological
chaI'a.cteri~ti~§,Jl:J;5!lt!J:c::>~to•..occur in the Susitna
basin.One form,trachurus,isanacfi:·omous:
Trachul:us usually enters coastaL-rivers Tntlie earTy
summer where it reproduces and then dies.The
juveniles rear for a short time in freshwater
habitats and then return to the marine environment in
late summer (Morrow 1980,ADF&G 1983m).The second
form,leiurus,spends its entire life in freshwater.
AthirdfOiiI1~semiarmatusispresumedto be present
although none have.been identified from project
sampli.ng.SemiarmaEusis aliybrid of trachtirtis and
leiurus (Wootton 1976).
E-3-2-46
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851021
The distribution of trachurus within the Susitna
drainage is limited to habitats with open access to
the marine environment.They have been observed in
mainstem,side sloughs,side channel and tributary
habitats.They have also been collected from lakes
with open access to the mainstem Susitna.Leiurus
are also found in these habitats as well as small
lakes and ponds with isolated drainages.No
populations of threes pine sticklebacks have been
found in the Susitna drainage upstream of Devil
Canyon.
Inter-population variation for several morphological
traits has been identified in the Pacific Northwest
(eg.,Hagen and Gilbertson 1972;Hagen and McPhail
1970;Moodie and Reimchen 1973).This extensive
variation indicates that the species is capable of
pronounced adaptation to local environmental
conditions.In studies conducted in Southcentral
Alaska within the Susitna River,Bell et a1.(1985)
identified"several populations in small,isolated
lakes that contained a high proportion of individuals
with reduced or missing pelvic spines and associated
anatomical structures.The importance of these
findings is uncertain at this time and all
populations are located outside the area which could
be affected by"the project.It is highly unlikely
that populations with such morphological variation
occur in habitats closely associated with the Susitna
River (that would be potentially exposed to effects
~f project operation)since a high degree of
isolation seems to be necessary for the evolution and
maintenance of these adaptations (Bell et a1.
1985).
(x)Cottids (**)
All sculpin species captured in the Susitna River
have been grouped under the general heading of
cottids.The slimy sculpin is the most common cottid
found in the Susitna,although there is a possibility
that three other species may be present below the
impoundment area.
Slimy sculpin are present in nearly all clearwater
habitats in the Susitna Basin.Adults and juveniles
occupy these areas and exhibit little movement
between habitats.Low densities of the sculpin are
also present in mainstem habitats (ADF&G 1983m,
1983b).
E-3-2-47
851021
Presumably,slimy sculpins represent a major predator
on salmon embryos and newly emergent salmon-fry.
(xi)Lamprey (0)
The Arctic lamprey,one of four lamprey species that
occurs in Alaska,was observed in the Susitna River
during 1981 (ADF&G 1981e).The Pacific lamprey,an
anadromous species that has been reported to range
into the lower Susitna River (Morrow 1980),wa..s not
observed during 1981 investigations.
Some populations of Arctic lamprey are composed of
both anadromous and freshwater forms.It was
speculated that a portion (30 percent)of the Susitna
poulation is anadromous,based on analysis of length
frequencies (ADF&G 1981e).The anadromous form is
parasitic;hosts include adult salmon,trout,white-
fish,ciscoes,sucker,burbot,and threespine
stickleback (Heard 1966).The freshwate~pforms have
been reported to be both parasitic and nonparasitic.
Arctic lamprey spawn during spring in streams with
low-to-moderate flow.Embryos develop into a larval
stage,which spend one to four years burrowed into
soft substrate.l,After an indefinite period,adults
migrate upstream to spawn.
--Arctic~-lampr.e.y-were--captured.at-14 sampling sites,.
.be tween RM 10 and RM 101,that were surveyed from
November 1980 through September 1981.During the
winter surveys,the only habitat site to produce
Arctic lamprey was Rustic Wilderness where one
lamprey was captured.This area is in the lower
river at RM 57.All other lamprey were collected
during the summer.Lamprey wer~not cQllected in the
~lIl]?0tl"~~dlr1l~_I~.~.9.at:re~,a~(ADF&G 1981e).
-·Tne1fignesf·~eatCli frequency wasreco"rdeo-··ourrngthe
September 1 to 15 sampling period.All lamprey taken
during this period were collected at tributary sites
downstream from RM 50.5.The lowest incidence of
capture for this species during the summer was
observed in the July 16-31,1981 sampling period
(ADF&G ·1981e);;
E-3-2-48
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851021
2.2.2 -Habitat Utilization (***)
Every river system provides a complex array of hydraulic and
physical conditions within which fish and other aquatic
organisms must exist.Through the process of natural selection,
each species has evolved to utilize specific sets of habitat
conditions from the array of conditions available in the system.
The suitability,availability and subsequent utilization by the
fish of specific areas within a river system are determined by
the physical conditions within and adjacent to the areas or
habitats.
On an instantaneous basis (i.e.at a given discharge in the river
at a specific time),the suitability,availability and
utilization of a particular area can be described by a relatively
few principle hydraulic and morphologic parameters.The
suitability of a particular area is dependent upon water depth,
water velocity,substrate composition and structural attributes
contributing to cover for the fish.This assumes that chemical
characteristics and temperature are within the tolerance limits
of the fish.It also assumes that there is sufficient food
available to support the fish.The availability of suitable
conditions is determined first by the presence of the particular
set of conditions suitable for a particu1arspecie~and secondly
by the continuity of the specific area with the rest of the water
body such that the fish maygain~aGcess to the area.
On a continuous basis,the suitability and availability of a
particular area is dependent upon discharge in the river and
season of the year.Also,the utilization of specific areas
within the river system is dependent upon the season of the year,
behavior a~d the habitat requirements of the species and life
stages present.
Within the Susitna River basin,specific areas have been
categorized into one of seven basic habitat types based upon
their instantaneous hydraulic and morphologic characteristics.
These seven habitat types are:
0 Mainstem
0 Side Channel
0 Tributary Mouth
0 Side Slough
0 Upland Slough
0 Tributary
E-3-2-49
851021
o Lakes and Ponds
Characteristics of these habitat types are described in Exhibit
E,Chapter 2 Section.2.1.
Each of these habitat types responds,to some degree,to changes
in mainstem discharge.Changes in mainstem discharge may change
water surface area and water quality,depth and velocity within a
specific habitat type.Aside from the basic changes in habitat
conditions asisociated with changes in flow,a particular site may
be categorized differently at different mainstem discharge levels
(EWT&A 1985b).For example,at a given discharge in the
mainstem,an overflow channel may convey mainstem water and would
be considered a side channel.At a lesser mainstem discharge,
the channel may no longer convey mainstem water but ·.will convey
local surface runoff,tributary flow,groundwater,or a combina-
tion of these and would be considered a side slough.
In addition to the response of habitat conditions to seasonal
changes in mainstem discharge,seasonal changes in water
temperature and suspended sediment concentrations influence the
suitability of-a particular habitats site for habitation by fish.
As discussed in Exhibit E,Chapter 2,dramatic seasonal changes
in discharge levels occur within the river.Summer discharge is
often 10 to 20 times the winter discharge.Also,the Susitna
River carries a considerable suspended sediment load 4u~ing the
summer,whereas,during the winter,the suspended sediment load
is low (Exhibit E,Chapter 2,ADF&G 1983k,1983e).
The seven habitat types identified above can be ranked ~ccording
to the sensitivity of habitat conditions within the sites to
changes in mainstem discharge (HE 1984b,1985a).This
sensitivity to mainstem discharge is described below with respect
to the proportion of time or the frequency with which mainstem
discharge directly affects habitat conditions and is summarized
in Table E.3.2.26~
_..>._-•._._._._.•_-~--•."••~_•
.Matnstemlil..!'easare by definition mos to changes in
mains tem di schargesTnce haM ta tc·onaItIonsTn·ternisof~surface
area,depth and velocity vary continuously with discharge.
Side channels are less sensitive but are directly affected by
mainstem discharge sufficiently great to breach the upstream ends
of the channels.In general,side channels convey mainstem water
more than 50 percen.t 6fthe time during the summer,openwater
seCison (SeeE'Xhibit E,Chapter 2 for discussion of discharge
regimes during summer vs winter months).
Tributary mouth habitats occur at the confluence of the
tributaries with the mainstem.The aerial extent of this habitat
E-3-2-50
type is dependent not
tributary discharge.
discharge will affect
only upon mainstem discharge but also on
To some extent both mainstem and tr-ibutary
the specific location of this habitat type.
Side sloughs are less responsive to mainstemdischarge changes in
that mainstem discharges sufficiently great to breach the
upstream ends occur less than 50 percent of the time during the
open water season.However,at lower discharge levels,the
mainstem discharge may affect slough habitat conditions,
particularly at the mouths,through backwater effects (ADF&G
1983k,1984r,19851).Mainstem discharge less than that
sufficient to breach the upstream end may also affect habitat
conditions through the influence on groundwater upwelling (See
Exhibit E,Chapter 2 Section 2.4;R&M 1985b,APA 1984g).
Upland sloughs are relatively insensitive to mainstem discharge.
The major effects on upland sloughs by changes in mainstem
discharge are changes in surface area,velocity and depth due to
backwater effects.Changes in mainstemdischarge generally will
not affect discharge or water quality parameters in the upland
I slough.
Tributaries,although continuous with the mainstem,are not
affected by changes in mainstem discharge.Habitat conditions in
tributaries are d~pendent only upon tributary discharge.
Similarly,habitat conditions in lakes and streams within the.
basin are unaffected by changes in mainstem discharge.In some
cases,the lakes or ponds are completely independent of the
mainstem with no interconnecting body of water.In other cases,
outlet streams from the lakes or ponds do provide a surface water
connection with the mainstem.
In describing existing conditions,and ultimately ~n evaluating
the effects of the Susitna Hydroelectric Project,it is necessary
to identify the utilization of the habitat types by the fish
species.The utilization of each habitat type is described below
in terms of the species present in the habitats;when they occur
in the habitats;the relative ~bundance of each species in the
habitats;and the significance of the habitat type to the
appropriate life stage of the species.As a matter of
convenience,the discussion is divided into three major reaches
of the Susitna River:1)The Oshetna Rivet to Devil Canyon (RM
233 to RM 152)representing the impoundment zone,2)Devil Canyon
to Talkeetna (RM 152 -RM 100)referred to as the middle river,
and 3)Talkeetna to Cook Inlet (RM 100 -RM 0)referred to as the
lower river.
851021 E-3-2-51
(a)Oshetna River to Devil Canyon (**)
The impoundment zone reach of the Susitna River flows
thro~gh a steeply cut channel that is in the process of
degrading the existing riverbed.From Oshetna River (RM
233)to Devil Creek,the river is wide and often splits into
two or more channels with an average gradient of
approximately 13 ft/mile (2.4 m/km).From Devil Creek (RM
162)to the downstream end of Devil Canyon (RM 150),the
river forms one channel that lies in a deep valley with an
average gradient of 31 ft/mile (509 m/km).Substrates
throughout the impoundment reach and mouths of tributaries
consist of rubble,cobble,and boulders,often embedded in
sand;gravels are present in some locations (ADF&G
1981f).
Utilization of the mainstem,tributaries and lakes within
this reach are described below.Only a few isolated side
sloughs,side channels and upland sloughs exist in this
reach and,therefore,are not considered an important
habitat component of the impoundment zone.Tributary mouth
habitats are discussed in conjunction with the descriptions
ofihe tributary habitats.Detailed data collected in this
reach are presented in ADF&G reports (ADF&G 1981f,1983b)0
(i)Mainstem Habitat Near the Confluence of Major
Tributaries (***)
-~-Species~0ccurrence-and~·Relat~ive··Abundance~(·***)
Of the five species of Pacific Salmon,only chinook
salmon have been observed upstream of the Devil
Canyon Dam site at RM 150 (ADF&G 1983a,1984h,
1985b).The lack of other salmon upstream of RM
152 is due principally to the hydraulic velocity
present in the rapids within Devil Canyon.Adult
....t;h:i,.nQQJ.(,w.~.!'~QQ§.~!'y~4J!l .t:h.~..!IlQt1t:1:l.I:1c:>LCh ee ch~!to
Creek,Chinook Creek,Devil Creek and Fog Creek....-_{ADF&G ·1985bY:-Peak index countsatthese---·······_··-.
locatidnsranging from 1to35 fish,indicate that
the relative abundance of chinook at these creeks
is quite low.
Seven resident species {Arctic grayling,longnose
sucker;-hillnpback whitefish;r(5Und~hitefish,Dolly
Varden,burbot and slimy sculpin (Cotd.d)~dso
dccurin the mairiste11l arid tributary 11louth habit:ats.
None of these species is present in high numbers at
the tributary mouths or in the mainstem.Arctic
grayling and Dolly Varden are more abundant in the
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851021 E-3-2-52
(II!,)
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851021
mainstem during the winter (ADF&G 1983b).Burbot
are present in the mains tern throughout the year
(ADF&G 1983b).
-Significance of Habitat (***)
The mains tern Susitna River provides overwintering
habitats for all species of resident fish occurring
in the impouridment zone (ADF&G 1981f,1983b).In
addition,mains tern and tributary mouth habitats
provide habitat for burbot,juvenile Dolly Varden,
round whitefish and humpback whitefish during the
summer.
(ii)Tributaries (***)
Eleven named and numerous unnamed tributaries flow
into the Susitna River within the impoundment zone.
The locations of the confluences of the tributaries
with the mainstem are given in Table E.3.2.27.
-Species Occurrence and Relative Abundance (***)
Arctic grayling,Dolly Varden,longnose suckers.
and cottids occur ~n tributary reaches within the
impoundment zone (ADF&G 1983b).Utilization of
tributaries is seasonal,with the major occurrence
during the Summer.In tributaries upstream of the
Watana Dam Site,Arctic grayling are the
predominant species.The total population of
Arctic grayling greater than 200 mm within the
impoundment zone is estimated to be about 19,000
fish (ADF&G 1983b).
Between the Devil Canyon and Watana Dam sites,
Dolly Varden tend to be the more abundant species
present in the tributaries.(~DF&G 1983b).
Chinook salmon spawning adults,embryos and fry
also may occur in the lower reaches of Chinook and
Cheechako Creeks within the Devil Canyon
impoundment zone since spawning activity has been
observed in these streams (ADF&G 1983a,1984h,
1985b).
--Significance of Habitat (***)
Tributary habitats in the impoundment zone provide
Summer spawning and rearing habitat for Arctic
E-3-2-53
851021
grayling.Because Arctic grayling require clear
water for spawning and rearing,the tributa~ies
provide significant habitat for the species.
The utilization of tributary habitat within the
impoundment zone by chinook salmon is insignificant
relative to the tributaries of the Middle River.
This is due principally to the low numbers of
chinook using these habitats (see Table
E.3.2.8).
(iii)Lakes and Ponds (***)
Thirty-one lakes and ponds occur within the
impoundment zone.Nearly all of the lakes and
ponds are small and shallow,ranging in size from one
to 55 acres.Only four of the lakes are sufficiently
deep to contain free water under the ice in winter.
The largest lake within the impoundment zone is Sally
Lake loaated near the confluence of Watana Creek with
the Susitna River.
-Species Occurrence and Relative Abundance (**)
Lake trout and Arctic grayling occur in Sally Lake.
The only other lake known to be inhabited by
Arctic grayling is on the south side of the Susitna
River near the Watana Creek confluence.
The lake trout population in Sally Lake is
estimated to be less than 1,000 fish (ADF&G
1983b).Arctic grayling in Sally Lake are more
abundant (approximately 5,000 fish).These fish
are apparently stunted since all fish collected
from the lake are relatively small (mean length of
42 fish =263 mm;range =220-325mm;(ADF&G
1983d).No estimate of the abundance of grayling
~...~In~EheunnamedTakersavaiTa-bre=
-Significance of Habitat (***)
The only occurrence of lake trout within the
impoundment zone is in Sally Lake.This
population is not considered important in the
contextofc thebroad~dist:~ibutionof lake trout in
the Susitna Basin,e.g.in Deadman Lake.
The small number and size of Arctic grayling in
Sally Lake compared to other lakes in the basin
E-3-2-54
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(e.g.,Deadman Lake)indicates that this lake is
not a significant habitat for grayling.
(b)Devil Canyon to Talkeetna (**)
In the reach of the Susitna River from Devil Canyon to
Talkeetna,the river channel is relatively stable and
straight with some meandering and minimal braiding.
Numerous islands,gravel bars,and sloughs are present.
Flow alternates between a single and split channels
configuration throughout the reach.Between Curry (RM 120)
and Talkeetna,the approximate gradient is 8.1 ft/mile (1.5
m/km).Typical substrate between Curry and Talkeetna is
gravel,rubble,and cobble with small amounts of sand and
silt.Above Curry the substrate varies from silt to
bedrock.The majority of mainstem shoreline substrate is
rubble and cobble whereas silt and gravel are the most
common substrate in sloughs and slow water areas.Below
Curry,streambank vegetation is dense spruce/hardwood
forest.In addition~to numerous smaller streams draining
the surrQunding hillsides,the principal tributaries to the
Susitna River in the Devil Canyon to Talkeetna reach include
Portage Creek,Indian River,Gold Creek,Fourth of July
Creek,Lane ~reek,and Whiskers Creek.
All of the seven habitat types identified above are
represented within this teach and are subject of effects of
altered discharge,temperature,ice processes and water
chemistry attributable to impoundment of the river by the
Susitna Hydroelectric Project.
Within this reach,habitats are utilized by the five Pacific
salmon species and all of the known resident species of fish
inhabiting the Susitna River basin with the exception of
lake trout.
The morphology,discharge regime,temperature and ice
regimes,water quality conditions and substrate composition
under existing conditions are described in detail in Exhibit
E,Chapter 2.The occurrences and relative abundances of
the fish species inhabiting the habitat types in the middle
river are described below.Also,the importance of each
habitat type for the respective life stages of each species
is also discussed.
(i)Mainstem Habitat (**)
The Susitna River from Devil Canyon to Talkeetna has
both single and split channel configurations
851021 E-3-2-55
(Figures E.3.2.18 throllghE.3~2.35).Single channel
reaches are generally stable with banks of b~drock or
a layer of gravel and cobbles.The channel is either
straight or meandering.In straight channel reaches,
the thalweg often meanders across the channel.
Occasional fragmentary deposits can be found in the
floodplain.Split channel configurations are
characterized by moderately stable channels with a
gravel/cobble substrate.There are usually no more
than two channels in a given reach.Channels are
separated by well established vegetated islands.
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
Five species of Pacific salmon utilize mainstem
areas primarily as a migration corridor.Life
stages of the salmon that occur in the middle
river are in migratingadults;"1spawning adults,
incubating embryos ,'.rearing juveniles and
outmigrating juveniles.
Adult chinook salmon utilize themainstem
primarilty as a migrational corridor to the
.spawning areas in tributaries (ADF&G 1981a,
1983a,1984h,1985b).Estimates of the number of
chinook adults using the mainstem habitats in the
midd Ie reach··.for19 81-1984~at'ecsumma,t'-ized.in..··.
Table E.3.2.6 and depicted in Figure E.3.2.5.
The timing of the occurrences of chinook adults
in the middle reach is depicted in Figure
E.3.2.7.Since chinook salmon do not use
mainstem areas for spawning,incubating embryos
are not present.As described in Section
2.2.1,juvenile chinook move into the mainstem as
..........___part.of theirdownstreaID.IDigra,tion to rearing
habitats:Elthi;mrddlElriver-~to··the Tower river,
or to Cook Inlet.Hence,mainstemnaortats serve--
as a migrational corridor for juvenile chinook
salmon as well as for adult chinook.
Adult sockeye similarly utilize the mainstem as a
migrational corridor.Estimates of the number of
sockeye migrating through the mainstem are
summarizediri.ta.Dle:E.3~2.6al1d depicted in
Figure E.3.2.5~The timing of adult sockeye in
the middle river is depicted in Figure
E.3.2.7.Nearly all sockeye adults spawn in
side slough habitat.However,a few adults have
851021 E-3-2-56
]
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851021
been observed to spawn in mainstem areas (ADF&G
1985b).The use of mainstem habitat for 'spawning
of adult sockeye is uncommon and,therefore,few
incubating embryos are in the mainstem.Juvenile
sockeye use the mainstem primarily as a
migrational corridor to other habitats for
rearing,overwintering and outmigration (ADF&G
1981d,1983m,1984c,1985c).
The utilization of mainstem habitats by the
various life stages of coho salmon is essentially
the same as for sockeye salmon.The estimates of
the number of coho adults present in the mainstem
for 1981-1984 are summarized in Table E.3.2.6
and depicted in Figure E.3.2.5.The timing of
adult coho in the mainstem of the middle river is
depicted in Figur.e E.3.2.7.A few coho salmon
have been observed to spawn in mainstem areas
(ADF&G 1983a).Juvenile coho,like sockeye and
chinook,use the mainstem as a.migrational
corridor to rearing and overwintering habitats
and for outmigration to the lower river (ADF&G
1983m,1984c,1985c).
Adult chum salmon utilize the mainstem primarily
as a migrational corridor to spawning areas:
Estimates of the'number of chum present in the
mainstem in 1981-1984 are summarized on Table
E.3.2.6 and are depicted in Figure E.3.2.5.The
timing of adult chum in the mainstem of the
middle reach is depicted in Figure E.3.2.7.In
the period 1981-1984,up to 4 percent of the
escapement of chum into the middle river (i.e.,
past the 'Talkeetna Station)and approximately 8
percent of the escapement past the Curry Station
spawned in mainstem areas (ADF&G 1985b).Hence,
incubating embryos do occur in mainstem habitats,
probably in areas of groundwater upwelling (ADF&G
1985a,1983k,EWT&A and WCC 1985;WCC 1985).
Juvenile chum salmon use the mainstem as a
migration corridor during their outmigration
from the middle river (ADF&G 1981d,1983m,1984c,
1985c)•
pink salmon use the mainstem only for
in-migration to spawning areas in tributaries and
for outmigration to Cook Inlet.The timing of
the adult and juvenile pink salmon in the
mainstem is depicted in Figure E.3.2.7.
Estimates of the number of pink salmon occurring
E-3-2-57
in the middle river in 1981-1984 are summarized
in Table E.3.2.6 and depicted in Figure E.3.2.5.
A summary of the utilization of the mainstem by
the various life stages .of the salmon-species is
presented in Table E.3.2.28.
•Resident Species (**)
The mainstemhabitat is used by all species of
resident fish known to occur in the middle
river (Table E.3.2.28).However,only burbot and
longnose sucker inhabit mainstem areas throughout
the year.The other species are present in the
mainstem only in the late fall,winter and early
spring.
-Significance of the Habitat Type (**)
The principle use of mainstem habitats by salmon
and resident species is as a migration corridor
......and.as.an.overwinteringarea.To_a.lesser degree,
the mainstem provides spawning habitat for chum
salmon,burbot,longnose suckers,and a few sockeye
salmon.Themainstem is utilized throughout the
year by burbot and longnose sUGker.
(ii)Side Channel Habitat (**)
Side channel habitats are generally
peripheral areas of the mainstem corridor.Side
channels have a diverse morphology with some having
broad channels while others are narrow and deep.
Side channel habitats are highly influenced by
mainstem discharge and water quality.In general,a
side channel habitat conveys less than 10 percent of
the total discharge in the river,but conveys
maiiiifteiii'aiscnat'ge'mcn:'e-than'50'p'ercentofthe-time
....--.....-..----...--..·-d1.1r ing:-·the-summerhrgh--fl-ow-months{EWT&A--·l-9 84,·····---··....·
1985b).Side channel habitats normally breach,Le.,
convey mainstem water,at mainstem discharges less
than 20,000 cfs (EWT&A and AEIDC,1985).
851021
Side channel habitats have relatively low velocity
.(less than 3,.,.4 ft/sec),.shalLow depths,and convey
turbid water during the summer.When mainstem
di-scharge·decreases ·in .the ·l.ite fal Laridwiiiter,.side
channels may become completely dewatered or may
convey water derived from loc:al runoff,tributaries
or upwelling groundwater.The distribution of side
E-3-2-58
1
851021
channels is depicted in Figure E.3.2.18 through
E.3.2.35).The utilization of side channel habitats
by the various life stages of salmon and resident
species is summarized in Table E.3.2.28.
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
The only life stages of salmon species observed
to use side channel habitats extensively are
juvenile chinook salmon,spawning chum salmon,
and incubating chum embryos (ADF&G 1983a,1983m,
1983k,1984h,1984c,1984b,1985b).A few
sockeye salmon adults have been observed spawning
in side channel habitats (ADF&G 1985b).
Side channels provide rearing habitat for the
largest proportion of juvenile chinook salmon
outside of the tributaries.Approximately 23
percent of the catch per unit effort for juvenil~
chinook is from side channel habitats·,(Figure
E.3.2.31 (ADF&G 1984c).The mean catch per
sampling cell for junvenile chinook increased
from the end of May and remained relatively high
through th~summer until mid,Dctober as depicted
in Figure E.3.2.37 (ADF&G 1984c).The high
densities of juvenile chinook in side channels
are probably due to the low velocity,shallow
depth and relatively high turbidity present in
side channels.Turbidity is apparently used by
juvenile chinook as a form of cover (ADF&G
1983a,1984c,1985c).The density of juvenile
chinook in side channels is considerably reduced
in late October and through the winter months.
Therefore,it appears that they do not use side
channels to overwinter (ADF&G 1983e,1985a).
Juvenile sockeye,coho and chum salmon utilize
side channel habitats to a limited extent.The
occurrence of these species in the side channels
is probably transitory and corresponds to the
out-migration of the juveniles from the Middle
River.The relative abundances of these
juveniles in side channels in terms of the
proportion of the catch per unit effort,are
presented in Figures E.3.2.38,E.3.2.39,and
E.3.2.40,respectively.The seasonal occurrences
of the species is presented in Figures
E.3.2.41,E.3.2.42 and E.3.2.43,respectively,as
E-3-2-59
the mean catch per unit effort in each sampling
period.
Some adult chum salmon use side channel habitats
for spawning (ADF&G 1983a,1984h,1985b).
Selection of side channels by chum salmon for
spawning is highly dependent upon the presence of
upwelling (see Section 2.2.3).
•Resident Species (**)
The only resident species known to utilize side
channel habitats is burbot.Adult and juvenile
burbot have been collected occasionally in side
channels when mainstem discharge is well above
that required to breach the upstream ends (ADF&G
1984c).
Significance of Habitat (**)
Side channels provide rearing habitat for
j uveni le·chinook -sa lmon.Al though a larger
portion of the catch per unit effort is observed
for tributary habitats,the sensitivity of the side
channels to mainstem discharge and the relatively
high propprtion of chinook juveniles in side
channels elevates the importance of this habitat
type in evaluating the effects of changes in
-------~c ----.-dischar.ge-and.cwater__q_u.cdity_at t'.t'iQl!.t:~1>l~to the
Susitna Hydroelectric Project.
(iii).Tributary Mouth Habitat (**)
The size and the lateral location of the available
tributary mouth habitat varies with mainstem
discharge and discharge from the tributary itself.
At high mainstemdischarge,the habitat tends to be"near Eheb8,iikvegeE.ition-a:t -t:he'motith'6fthe
.--trioutary ,-wnereas-a:t--l:-6w-marnst"em-di-scharge,the··'
habitat is further away from the bank vegetation.
Tributary mouth habitat is more obviously defined in
summer than in winter because tributary water can be
distinguished from mainst;em water by the extreme
differences in their respective turbidities.
Tributary mouth habitat extends from upstream in the
tri'bl.lta.:ry,.a.t:the point whe.re backwater effects from
the mainstem are observed,into the mainsliem where
mainstem water mixes with the tributary water.This
is obvious during the summer when the mainstem water
is turbid and the tributary water is clear.At times
J
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851021 E-3.,..2-60 .)
i I
j
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I
j
.851021
the tributary mouth habitat can extend downstream as
much as one mile (ADF&G 1983k,1984s,EWT&A 1985b).
The utilization of tributary mouth habitat by various
life stages of salmon and resident species is
summarized in Table E.3.2.28.
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
The utilization of tributary mouth habitat by
salmon is limited.Adult salmon that use
tributary habitat for spawning (chinook,coho,
chum and pink)have been observed to hold at
tributary mouths prior to entering the
tributaries to spawn (ADF&G 1983a,1984h,1984s,
1985b).A few chum have been observed to sp~wn
in tributary mouth habitats,particularly at the
mouths of 4th of July Creek and Indian River
(ADF&G 1983a,1984h,1984s).For the most part,
however,adult salmon use tributary mouth habitat
as a migration corridor between the mainstem and
tributary spawning areas.
Incubation of chum salmon embryos deposited in
tributary mouth habitats is likely to be limited
and relatively unsuccessful because of the
movement of the tributary mouth habitat away from
the deposition sites as mainstem .and tributary
discharges decreases in the fall.Chum redds
become dewatered and are subject to freezing
(ADF&G 1984s).
Juvenile salmon utilize tributary mouth habitat
primarily as a migration corridor from the natal
tributaries into the mainstem.Chinook and coho
juveniles will remain in the habitat in the
summer and can be collected from the mouths in
August and September (ADF&G 1983m,1984c).
Presumably,the juveniles inhabit these areas to
feed on drifting aquatic invertebrates from the
tributaries (ADF&G 1983m,1985j)or salmon eggs
dislodged from the spawning areas (ADF&G
1983m).No overwintering juvenile salmon have
been observed at tributary mouth habitats •
•Resident Species (**)
All of the resident species present in the middle
river become associated to a greater or lesser
E-3-2-61
851021
degree with tributary mouth habitats at some time
during the year.Rainbow trout move through
tributary mouth habitats into tributaries for
spawning and rearing (ADF&G 1983m).In early
fall,adult and juvenile rainbow congregate at
tributary mouth habitats to feed on dislodged
salmon eggs and to overwinter.Arctic grayling,
Dolly Varden,and other resident species use
tributary mouths in a similar fashion.Burbot
are not generally present in tributary mouths
(ADF&G 1983m,1983b,1984c).The longnose
sucker is the only species that appears to be
associated with tributary mouth habitats
throughout the year (ADF&G 1983m 1984c).
-Significance of Habitat (**)
The major use of tributary mouth habitat by salmon
is as a migrational corridor.Use of tributary
mouth habitat for spawning,incubation and rearing
is limited.Resident species use tributary mouth
habitat for migration into and from tributaries
and,to a seasonally limited extent,for rearing.
(iv)Side Slough Habitat (**)
Side slough habitats are morphologically similar to
side channel habitats and distinctions between side
-----slough---and-·s-ide-channe·1-s~a-t'e-somewhat-a-rbi tra-t'y
(EWT&A 1985b).Side sloughs are distinguished from
side channels in that mainstem discharges greater
than approximately 20,000 cfs are required to breach
the upstream ends.Hence,side sloughs convey
mainstem water less than approximately 50 percent of
the time during the summer high flow months.
....!\~.II1.a i n ~.t_li!lllcl~~c:l1_.a_;:gli!.EiJ§lfll:1_!:l1.al!tl1l:lt;_;:~_qtJi~_~(L~g _.
breach the upstream ends,the side sloughs convey
clear water.The clear water Is derived from local
surface runoff,small tributary outflow and upwelling
groundwater (R&M,wee &HE 1985;R&M 1985b;APA
1984g;ADF&G 1983k; 1984v;1984r;19851;wee
1984a,b).The total clearwater discha,rge in the
side sloughs is dependent upon storm events and rates
ofgroUtidwater upwelling-(R&M 1985b;APA 1984g).
Habitat cOtiditions-withititJie niouth of side Sloughs
at mainstem discharges less than breaching are also
affected by backwater effects of mainstem stage.The
stage in'the mainstem controls the water surface
E-3-2-62
1
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851021
elevation of the lower portion of the sloughs by
forming a backwater that extends some distance
upstream into the slough (ADF&G 1983k,1983n,
1984r,19851).This backwater is divided into two
parts -clear water and turbid water.The mainstem
water creates a turbid plug at the mouth that backs
up clear water in the slough.As the stage in the
mainstem drops,the size and character of the
backwater changes.When mainstem discharge is
between approximately 8,000 to 10,000 cfs at Gold
Creek (RM 136.8),the backwaters are minimal at most
side sloughs (ADF&G 1983k).A consequence of low
mainstem discharge is that the depth of water at the
entrance to the sloughs is reduced (ADF&G 1984r,
19851).A more detailed description of the
hydrolog~c and water quality characteristics of side
sloughs is presented in Exhibit E,Chapter 2.The
utilization of side slough habitats by salmon and
resident species is summarized in Table E.3.2.28.
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
Various life stages of all five salmon species
utilize side slough habitat during the year.
Although chinook salmon do not spawn in side
sloughs,juvenile chinook move into these
habitats in September to overwinter (ADF&G
1983e,1983m;1983n).The increased number of
juvenile chinook in side sloughs is depicted in
Figure E.3.2.37.Side sloughs also provide
rearing habitat for juvenile chinook throughout
the summer,but the proportion of the catch per
unit effort in side sloughs is less than 10
percent (Figure E.3.2.36).
All but a few adult sockeye salmon spawn in side
slough habitats (ADF&G 1983a,1984h,1985b).
Peak escapement counts are depicted in Figures
E.3.2.8 through E.3.2.13.Estimates of the total
number of sockeye salmon spawning in each slough
from 1981-1984 are summarized in Table
E.3.2.12.Incubating sockeye embryos are present
in the side sloughs throughout the winter months.
Once the fry emerge from the gravels,Age 0+
juvenile sockeye remain in side sloughs for a
short time before out-migrating in July and
August (ADF&G 1983m,1984c)as indicated in
E-3-2-63
Figure E.3.2..41 by the reduced mean catch per
cell.In 1983,44 percent of the catch per unit
effort of sockeye juveniles was from side slough
habitats as depicted in Figure E.3.2..38.Some
sockeye juveniles overwinter in side sloughs but
their occurrence is limited (ADF&G 1981d,1983e,
1985a).
A few adult coho salmon have been observed in
side sloughs (ADF&G 1983a,1984h).Some juvenile
coho move into side sloughs to rear but the
proportion is relatively small,less than 10
percent of the total coho catch per unit effort,
(ADF&G 1984c)as indicated in Figure E.3.2..39.
The densities of coho juveniles appear greatest
in July (Figure E.3.2..2.4 probably coinciding with
redistribition of the juveniles from natal areas
to rearing areas (ADF&G 1984c).
Up to 30 percent or more of the chum salmon
spawning in the middle river occurs in side
slough habitats (ADF&G 1981a,1983a,1984h,
1985b).Peak escapements to each of the sloughs
is depicted in Figures E.3.2..8 through E.3.2..13
and estimates of the number of chum salmon
spawning in each slough each year from 1981-1984
are presented in Table E.3.2..19."Incubating chum
embryos are present in the side sloughs through
Juvenile chum remain in side sloughs prior to
out-migrating from th~middle river.The
relative proportion of juvenile chum catch per
.unit effort collected from side sloughs in 1983
is depicted in Figure E.3.2..40.Juvenile chum
leave the side slough habitats by the end of
June (Figure E.3.2..43,ADF&G 1983m,1984c)•
'J
J
,~\
J
..-..~.--····~c····_··_··~··_·-A-·few..pink.salmon.ut.il.ize.sidesloughs--fo.r.··.---·..----
spawning as indicated in Figures E.3.2..8 through
E.3.2..13.The total number of pink salmon found
in side sloughs each year is dependent on the
size of the escapement.During even years,use
of side sloughs for spawning is higher than
'.cltl:t'illg Oclcl..yea.rs(seeSe«;:don 2..2..1.a.v)•
I >j
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85102.1 E-3-2.-64
I
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851021
•Resident Species (**)
All resident species reported in this reach of
the Susit~a River have been observed in slough
habitat.
Available data indicate that most resident
species are present in sloughs as well as the
mainstem throughout winter (ADF&G 1981e,
1983e,1985a).During summer,most adult
residents are not abundant in sloughs (ADF&G
1983m,1984c).Those that were relatively
abundant in slough mouth habitat during summer
included burbot,longnose sucker,and rainbow
trout.Previous studies indicated that juvenile
whitefish,grayling,and rainbow trout were
abundant in slough habitat during late summer
(Friese 1975).
-Significance of Habitat (**)
A summary of the occurrence of the various life
stages of salmon and resident species which use
side sloughs is presented in Table E.3.2.28.The
most important use of side sloughs is by chum and
sockeye salmon for spawning and incubation of :
embryos,by juvenile chum,sockeye and coho for
rearing and by sockeye,coho and chinook juveniles
for overwintering.
(v)Upland Sloughs (**)
Upland sloughs are analogous to small tributaries
(EWT&A 1984,ADF&G 1983n).Discharge in upland
sloughs is derived from local runoff,small
tributaries and groundwater upwelling.Many of the
upland sloughs are inhabited by beavers.The
upstream ends of upland sloughs are often separated
from the mainstem by vegetated areas indicating that
breaching of the upstream end occur only at extremely
high mainstem discharge.Upland sloughs are depicted
in Figures E.3.2.l8 through E.3.2.35.The principle
influence of mainstem discharge on upland sloughs is
through.the backwater effect of mainstem stage (EWT&A
1984,ADF&G 1983k).The utilization of upland
sloughs by salmon and resident species is summarized
in Table E.3.2.28.
E-3-2-65
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
The principle use of upland sloughs by salmon is
as rearing habitat for juvenile coho and
sockeye.The relative importance of upland
sloughs to sockeye and coho is evidenced by the
large proportion of catch per unit effort
represented by upland sloughs depicted in Figures
E.3.2.38 and E.3.2.39.Upland sloughs are also
used by sockeye,coho and chinook juveniles for
overwintering (ADF&G 1983e,1985a).Generally,
the juveniles become abundant in upland sloughs
in mid to late June and remain at higher
densities through September and.October as shown
on Figures E.3.2.41 and E.3.2.42,respectively
(ADF&G 1983m)."'
•Resident Species (**)
The·onlyresident species to be collected from
upland sloughs in any abundance is rainbow
trout,although individuals of all species have
been collected in upland sloughs (ADF&G 1981e,
1983m,1984c).
The primary use of this habitat type is for rearing
and overwintering by juvenile sockeye and coho
salmon as shown in Table E.3.2.28.
(vi)Tributary Habitats (**)
Tributaries that flow into the middle Susitna River
all convey clear water into the river.The two....maj or-trIoutarTesofEl1e-MidctTeRiver-are ···Iucfiliiu
...--------+.--.------.----.---.--.---------+~.---~----------R-i ver --'-ana~Porfage ~Cr-eelf-;-e-acn 0 f--wlficn--nave .an -annual------
average discharge of approximately 500 cfs.Numerous
other tributaries that flow into the middle river are
identified in Figures E.3.2.8 through E.3.2.l3.The
utilization of tributary habitat by salmon and
resident species is summarized in Table E.3.2.28.
:.)
,)
;)
1\
)
851021 E-3-2-66
851021
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
All life stages of chinook,coho,chum and pink
salmon occurring in the middle reach utilize
tributary habitat as depicted on Table E.3.2.28.
The relative abundances of these species in
tributaries are discussed partially in Section
2.2.1.a and are summarized below.
The relative abundance,as evidenced by peak
escapement counts of adult chinook salmon in
middle reach tributaries,is summarized in Table
E.3.2.9.Indian River and Portage Creek provide
spawning habitat for the majority of the chinook
using the middle river.Juvenile chinook remain
into the tributaries at relatively high densities
for approximately two months before some begin to·
move downstream into the mainstem.Approximately
61 percent of the catch per unit effort of
chinook was from tributaries as depicted in
Figure E.3.2.36.Chinook juveniles tend to
remain in the tributaries throughout the
summer(Figure E.3.2.37)and some juvenile chinook
remain in the tributaries throughout the winter
and out-migrate to the mainstem in June and July
the following year (ADF&G 1983m,1984c).
The relative abundance of coho salmon using
tributaries of the middle reach as indicated by
peak index counts are summarized in Table
E.3.2.l5 and are depicted in Figures E.3.2.8
through E.3.2.l3.Whiskers Creek,Indian River
and Gash Creek provide spawning habitat for the
majority of coho in most years.As with chinook
salmon,incubating embryos occur in the
tributaries in direct proportion to the number of
adults spawning in the tributaries.Following
emergence of the juveniles,many remain in the
tributaries with over 50 percent to the catch per
unit effort obtained from tributary habitat
(Figure E.3.2.39)(ADF&G 1984c).Juvenile coho
tend to remain in tributary habitats at high
densities throughout the summer as indicated by
the high catch per unit effort through the summer
months (Figure E.3.2.42).Some reduction in the
densities occurs as juveniles move out of the
tributaries into side sloughs and upland sloughs
E-3-2-67
(ADF&G 1983m,1984c).Tributaries also provide
overwintering habitat for coho juveniles.
Approximately 50 percent or more of the chum
salmon spawning in the middle river spawn in
tributary habitats.Peak index counts are
summarized in Table E.3.2.18 and are depicted in
Figures E.3.2.8 through E.3.2.l3.Chum embryos
are present in direct proportion to the number of
adults spawning in the tributaries.Juvenile
chum remain in the tributaries until early July
(Figure E.3.2.43)when they out-migrate from the
system.Approximately 34 percent of the catch
per unit effort of chum juveniles was from
tributary habitat (Figure E.3.2.40).
pink salmon utilize a number of tributaries for
spawning,particularly some of the smaller
streams,as summarized in Table E.3.2.20 and
depicted in Figures E.3.2.8 through E.3.2.13.
Juvenile pinks out-migrate from the tributaries
upon emergence almost immediately after the river
becomes ice free in the spring.Hence,no
rearing of juvenile pink occurs in tributary
habitat.
•Resident Species (**)
AH:q~s:i.ci.a!!l:/;JJ)..a_c::i..af:lp:re/;J..ant inl:ll..a middle riY~:r,
with the exception of burbot and round
whitefish sculpins,utilize tributary habitats
for spawning and rearing during summer (ADF&G
1983m,1984c).During winter,resident species
tend to move out of tributaries to overwinter in
the mainstem.
-Significance of Habitat (**)
Tributari-es-provi-deimportant--habi-tat-for near-l-y-
all species of salmon and resident species .
occurring in the middle river.Tributary habitat
conditions provide the base for the majority of
fish production occuring within this reach.
(c)Cook Inlet to Talkeetna (*:*)
..The lowerSusitna River is moderately to extensively braided
throughout most of the reach.From Cook Inlet to Bell
Island (RM 10),the river is separated into two braided
channels;from Bell Island to the Yentna River (RM 27),a
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851021 E-3-2-68
851021
single meandering channel is formed.From the Yentna River
to Sheep Creek (RM 70),the river is moderately to'
extensively braided,with forested islands and nonforested
bars between the channels of the river.The river is
reduced to a single channel near the Parks Highway Bridge
(RM 84),and braiding is moderate from this point upstream
to Talkeetna,(R&M Consultants and EWT&A 1985b).Gradients
vary considerably in this reach.From Cook Inlet to RM 50,
the gradient is 1 ft/mile (0.2 m/km);from RM 50 to 83,it
is 5.9 ft/mile (1.1 m/km);and from RM 83 to Talkeetna,the
gradient is 6.9 ft/mile (1.3 m/km).Typical substrate in
the reach is silt and sand with some gravel and rubble.
Major tributaries include:Alexander Creek,Yentna River,
Kroto Creek (Deshka River),Chulitna River,and the
Talkeetna River.Flows in these tributaries are
considerable.The Chulitna and Talkeetna Rivers contribute
about 57 percent of the total flow below the confluence near
Talkeetna (APA 1983b).
A more complete description of the morphological character
of the lower river is presented in Exhibit E,Chapter 2 and
complete aerial photographic coverage is presented in R&M
Consultants and EWT&A (1985b).The lower river channel is
relatively unstable in that the main channel changes through
time.These changes can occur relatively rapidly,primarily
as a result of floods with some influence by ice processes
(Exhibit E,Chapter 2~Section 2.3.2).Changes in channels
over the recent past are described in R&M Consultants and
EWT&A (l985b)•
All seven habitat types described for the middle river are
present in the lower river.However,upland sloughs and
lakes comprise a relatively small proportion of the total
area of the reach and,therefore,are not discussed below.
Because of the extensively braided character of the lower
river,distinction between side sloughs and side channels is
not as easily defined as for the middle river.Also,side
channels and side sloughs are intricately intermixed into
complex channel configurations.Therefore,side channels
and side sloughes are treated together as side channel
complexes.
(i)Mainstem Habitat (**)
Braided river reaches such as the lower Susitna are
characterized by two or more interconnecting
channels separated by unvegetated or sparsely
vegetated gravel bars.The active floodplain is wide
and contains numerous high water channels and
occasional vegetated islands.Active channels are
E-3-2-69
851021
typically wide and shallow and carry large quantities
of sediment at high flows.Bars separating·the
channels are usually low,gravel-surfaced,and easily
erddible.The lateral movement of channels within
the active floodplain of a braided river that carries
large quantities of bedload is expected to be high.
The channels shift either by bank erosion or by
channel diversion into what was previously a
high-water channel.Gravel deposits may partially or
fully block channels,thereby forcing flow to develop
a new channel.
Because braided river channels are wide and shallow,
they are more sensitive to flow reductions than the
deeper channels of a split channel system,i.e.,a
drop in stage could result in a substantial reduction
in the width of the river and loss of.large wetted
areas along the margins of the channel.
-Species Occurrence and Relativer<Abundance (**)
,;-Salmon (**)
Adult salmon pass through this reach of the
mainstem during their spawning migration.
Generally,the migration extends from late May
into September (specific dates are reported in
Section 2.2.1.a).The relative abundance of
adult-salmon--in -th-is--reach-ci-s--high=becausethe
entire salmon run must pass through the lower
sections of the river in order to arrive at
spawning grounds.Population estimates of the
number 'of salmon that pass various escapement
monitoring stations are given in Table E.3.2.6
and Figure E.3.2.5.
Spawning ofadult salmon and :rearing _of juvenile
safrttonhave-not-been:-do-Cumentedlii-mafristem--
areas.JuveniTe'-cliinooK anasOCKeye salmon-are-
abundant in some mainstemareas during winter
(ADF&G 1983e).Some juvenile coho are also
present in the mainstem but are more often
associated with tributary mouth habitats during
the winter (ADF&G 1983e).The mainstem also
provides "a"migration corridor for out migrating
juveniles.
E-3-2-70
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•Other Anadromous and Resident Species (**)
Other anadromous species observed in this reach
include Bering cisco and eulachon.Although
spawning activity by Bering cisco may occur
throughout the reach between RM 30 and RM 100,
three spawning areas were identified in mainstem
areas (ADF&G 1983a).Eulachon were observed in
the lower 58 miles of the lower river in 1981
(ADF&G 1981a),in the lower 48 miles in 1982
(ADF&G 1983a),and in 1983,eulachon were
observed below RM 50 (ADF&G 1984h).A complete
description of eulachon migration and spawning is
presented in ADF&G (1984h).Habitat use of
eulachon for spawning is described by ADF&G
(1984q)•
Burbot and longnose sucker are present throughout
the year and utilize the mainstem for over-
wintering,spawning,and juvenile rearing.
Habitat utilization within the mainstem is
probably similar to that previously discussed for
the middle river.
Apparently,burbot spawn at the mouths of the
Deshka ~iver and Alexander River in December and
January (ADF&G 1985c).juvenile and adult burbot
inhabit the lower river throughout the year.
Densities of habitat in the lower river are
higher than in the middle river or impoundment
zone.
Arctic grayling,rainbow trout,Dolly Varden,and
round whitefish are resident fish that use the
mainstem as a migratory channel to tributary
spawning habitat and as overwintering habitat.
Movement from tributaries to the mainstem for
overwintering is inferred from radio-tracking
studies of rainbow trout in the lower river
(ADF&G 1983m).
-Significance of Habitat (**)
The primary use of lower river mainstem habitat by
salmon is as a migration corridor for both adults'
and juveniles.The mainstem is also used to some
extent for juvenile rearing and overwintering.The
mainstem is also important for spawning of Bering
cisco and eulachon.Burbot and longnose sucker are
year-round inhabitants of mainstem habitat.These
E-3-2-71
habitats provide a migration corridor for rainbow
trout,Arctic grayling,Dolly Varden,and-round
whitefish as well as overwintering habitat for all
of these species.
(ii)Side Channel Complexes (**)
Side channel complexes consist of numerous inter-
connecting channels that are sensitive to changes in
total discharge in the river.
-Species Occurrence and Relative Abundance
•Salmon (**)
Juvenile chinook salmon,chum,and sockeye
utilize side channels for rearing.Highest .
catches of juvenile chinook were from moderately
turbid (less than 200 NTU)areas of side channel
complexes.Juvenile chum and sockeye,on the
other hand,were collected in greater number in
the clearwater,slough areas within the side
channel complexes (ADF&G 1985c).
1
851021
Some chum,sockeye and pink salmon spawn in side
channel side slough complexes {ADF&G 1981a,
1985b).It is evident,however,that side
channel complexes provide spawning habitat for
·--··small-~f-rac"1;'-ions~of~t;.he·t;.otal-·popu1cations of "I:;hes e
species (ADF&G 1981a,1985b)•
•Resident Fish (**)
The occurrence and relative abundance of resident
specie:occupying side channel side slough
complexes are similar to that described for
"lJ1i <i..Q1 ~.....l:'i,,~l:'s_j.<i.~...~11~111l.~1fl ~1l<i..flJ.Q~.fl1 C>.tl gh fl·
Burbot,longnose sucker and rainbow trout are the
more abundant resident species occupy-rng this····-
habitat type (ADF&G 1981e,1985c).
-Significance of Habitat (**)
As with the side channels and side sloughs present
.in "the middle river,sidechannel complexes of
the lower river provide important spawning habitat
forchWli saliJiori;"andoverwiiit::eririg habil::at::for
chinook and sockeye juveniles.
E-3-2-72
1
851021
(iii)Tributary Mouth Habitat (**)
Tributary mouth h~bitat in the lower river is similar
to that described for tributary mouths of the
middle river.The major difference is that four of
the tributaries,Yentna,Kashwitna,Talkeetna and
Chulitna,are of glacial origin and,therefore,do
not have clearwater plumes that extend into the
mainstem.
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
Utilization of tributary mouth habitat by salmon
species is similar to that described for the
middle reach.Upstream migrating adult salmon
tend to congregate in clear tributary mouths to
rest prior to resuming their upstream migration.
The major difference in the use of lower river
tributary mouths by salmon is that these habitats
provide the major rearing and overwintering
habitat for juvenile chinook,sockeye and coho
(ADF&G 1981e,1983m,1985c).Within the
tributary mouth habitats,juveniles use deep,low
velocity clearwater areas with overhanging and
emergent vegetation or undercut banks (ADF&G
1985c):In 1981 ~nd 1982,95 percent of all
chinook juveniles collected in the lower reach
were captured in tributary mouth habitats.
•Resident Species (**)
The occurrence and relative abundance of resident
species in tributary mouths is similar to that
described for the middle river.
-Significance of Habitat (**)
Tributary mouth habitat provides important rearing
areas for juvenile chinook,sockeye and coho
salmon.They also provide resting areas for
upstream migrating adults of all salmon species.
Tributary mouths also provide substantial rearing
and overwintering areas for all resident species.
E-3-2-73
851021
(iv)Tributary .Habitat (***)
Tributaries in the lower river constitute a major
portion of.the total habitat available for fish and
also contribute nearly 80 percent of the total
discharge from the drainage basin.The ¥entna River
contributes approximately 40 percent of the total
discharge,the Talkeetna River approximately 10
percent and the Chulitna River approximately 20
percent whereas the middle Susitna River contributes
approximately 20 percent of the total discharge from
the basin (USGS 1983).The remaining 10 percent of
the discharge is contributed by intervening,mostly
clearwater,tributaries.The Kashwitna River is of
glacial origin and is turbid during the summer.
-Species Occurrence and Relative Abundance (**)
•Salmon (**)
Tributaries of the lower river serve as spawning
habitat for more than 90 percent of all salmon
utilizing the Susitna River (Table E.3.2.6).As
such,the tributaries provide significant
incubation and rearing habitat for salmon as well
as migration corridors •
•Resident Species (**)
The occurrence and relative abundance of resident
species in the tributaries of the lower river
is similar to that described for the tributaries
of the middle river.
-Significance of Habitat (**)
'rd.P~t~:t"Yl:gtb!f:~ts;,1'_,,-~ll.<:l.ea rwa t er ..and turbid,
.__......~_provide the primary habi ta·!:for··saitno~·and-.
resident species within 'the Susitna Basin ..""_Because
each of the tributaries is independent of effects
of mainstem Susitna River discharge,no effects,
attributable to the Susitna Hydroelectric Project
are expected.
A'partIcular set o£·physIcal habifaEcharactefistics caribe
readily defined under steady state or instantaneous conditions.
However,habitats,particularly in riverine systems,tend to
change continuously through time and,therefore,are dynamic
E-3-2-74
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habitats.As flow or discharge in a river changes,basic habitat
characteristics such as water depth,water velocity and-total
habitat area at a given site will also cha~ge.In order to fully
understand the relationship between the occurrence and abundance
of fish populations in a particular system,it is necessary to
describe how a specific habitat area responds to flow changes.
An appropriate method to evaluate the habitat response to flow
change is to define the physical habitat at several instantaneous
discharges,simulate the conditions using a mathematical model,
and interpolate the conditions for intervening flows.
The process for describing habitat response to changing discharge
in the Susitna River is described below.Briefly,the first
step of the analysis is to describe how the total wetted surface
area of the river changes with flow •.Since the total wetted
surface area includes a diverse array of habitat types,the
second step is to subdivide the 'total surface area into rela-
tively discrete categories.The third step of the process is to
select habitat/lifestage combinations most sensitive to mainstem
discharge (HE 1984b,1985a).Once the species to be analy~ed y
have been selected,the fourth step is to determine the par-
ticular responses of suitable physical habitat conditions for
those species to discharge changes.
Since the wetted surface area does not necessarily describe the
habitat conditions present under the surface,it is necessary to
define what proportion of the surface area in a site contains
suitable physical habitat characteristics such as depth,
velocity,substrate or cover.The relationship between the total
surface area and proportion containing suitable habitat is then
calculated through a range of site or mainstem flows.By
comparing depth,velocity,and substrate or other habitat
characteristics present in the area with the ranges of these
characteristics which are suitable for fish,an estimate of the
usable area in the habitat sites through a range of flows can be
made.These estimates of the habitat areas at given flows in
turn can be used to quantify the response of the habitat area to
flow.A description of the response of habitats to flow through
time is then possible by comparing the flows in a given increment
of time with the habitat response curves.
The focus of the analysis presented below is for the middle
river since the flows in this reach will be most directly
affected by the Project.Downstream from Talkeetna,discharge in
the Susitna River is highly influenced by discharge from the
Chulitna and Talkeetna Rivers and,therefore,response of
habitats to changes in flow attributable to the project are
attenuated.Data are available,however,to perform the analysis
as described below for the middle river.(ADF&G 1985b;HE
851021 E-3-2-75
(a)Surface Area Response to Flow Changes (***)
The total wetted surface area of the middle river was
measured from aerial photographs representing seven
mainstem discharges measured at the USGS Gold Creek Gaging
Station (EWT&A 1985b).The discharges were 5,100 cfs,7,500
cfs,10,600 cfs,12,500 cfs,16,000 cfs,18,000 cfs and
23,000 cfs.The surface areas for each discharge area were
measured with a digital planimeter from the aerial
photographs printed at a scale of 1 inch to 1,000 ft,as
described by EWT&A (1985b).Examples of the aerial
photographs used for measuring total surface at 23,000 and
12,500 cfs areas are presented in Figures E.3.2.18 through
E.3.2.35.
In the process of measur~ng the total surface areas,dis-
crete habitat type areas were delineated.The same habitat
type delineations were retained on each set of aerial photo-
graphs so that the surface areas of.the sites at each·flow
could be.Co Dlpareci •.The delineation of the'·sites at each of
the flows is exemplifiedi.n compal:-:lson 0·£the upper (23,000
cfs)and lower (12,500 cfs)panels in each of the Figures
E.3.2.18 through E.3.2.35 (EWT&A 1984).
The initial classification·of the total wetted surface areas
was ba.sed upon the seven habitat types described in Section
___~.2.2.Two of theseyen habitat types,lakes and tributar-
ies ,-werenotTncluded -[It ttieanafysis since-me -surface·
areas do not change with mainstem discharge changes.Hence,
the total wetted surface areas were initially categorized
into mainstem,sidechannel,side slough,upland slough and
tributary mouth habitat types.In some cases,the inclusion
of a particular site in the areas of side channels or side
sloughs did not remain the same for all discharges.At a
given flow,if.the particular site was conveying turbid
..mainstem--water·,.thesurfacea·rea-of.-thatsitewas .included
··---as-a-s·ide-channe-l-.-I-f-a.t-a-lo:wer.:_Jnains.tem_dj,~cha r g§..,t he ~_
site was conveying clear water,the surface area was
classified as a side slough (EWT&A 1985b).
The surface areas of the respective habitat classes at each
of the seven mainstem discharges are summarized in Table
E.3.2.29 and .a:t:'<?c:iepi.c:t:edin Figure E.3 .2.44.The.total
surface area of the·mainste~·increa:ses -as malnstem discharge
..increases..•Si1l1ilarly,the.tota1wetl::ed$uri:a.c:~()J side
channel habitats increases with increasing mainstem
discharge however,the rate of increase is somewhat
I
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851021 E-3-2-76
u
different than in the mains tern due in part to differences in
the channel morphology.Most of this surface area-increase
is due simply to the fact that more water in the riYer
results in more surface area.However,part of the increase
is due to the transformation of side slough into side
channel habitats (EWT&A 1984).Also at higher discharges
(e.g.greater than 16,000 cfs)some side channels transform
to mains tern areas and as a result,the relative increase in
side channel surface area is not as great as at somewhat
lower discharges.
The decrease in the surface area of side sloughs at
progressively higher discharges is due primarily to the
transformation of clearwater side sloughs to turbid water
side channels.(Table E.3.2.29,and Figure E.3.2.44).
Upland slough areas remain relatively constant at all-
mainstem discharges greater than approximately 7,500 cfs.
This is indicative of the relative independence of these
areas from mainstem discharge.(See Table E.3.2.29 and
Figure E.3.2.44).
Surface areas of tributary mouth habitat show no consistent
changes with respect to mainstem discharge.As discussed
previously,this is because the total area of tributary
mouth habitats varies wi th both mainstem .and tributary >,
discharge.For purposes of the following discussion,·the
response of tributary mouth habitat to changes in mainstem
discharge is not considered further because of this evident
inconsistent relationship.A more detailed discussion of
the relationship is presented in ADF&G (1984s).
(b)Development of Representative Groups of Habitat
Sites (***)
Although the classification of habitat areas into one of the
five habitat types outlined above gives a first level
picture of how habitat areas respond to flow change;inspec-
tion of the aerial photographs and data from specific habi-
tat study sites (ADF&G 1983k,1984b,1984i;EWT&A 1984,
1985b;EWT&A and AEIDC 1985)indicates that a more refined
level of classification is necessary to adequately analyze
habitat response to flow with respect to specific habitat/-
species combinations.The classification of sites into
representative groups was accomplished by first delineating
167 specific sites within the middle river.The apparent
flow conditions in each of the sites was evaluated on the
seven sets of aerial photographs to determine the basic
response of the habitat to change in mains tern discharge.In
order to identify the basic response of the site a flow
851021 E-3-2-77
chart was developed to track and characterize the response
of each site to decreases in mainstem discharge.This flow
chart is presented as Figure E.3.2.45.The response of a
particular habitat site or specific area was based on
comparison of the habitat type at that site at 23,000 cfs
with the habitat type at that site ata lower discharge ••
Thus,if at 23,000 cfs the site was a turbid side channel,
and at 16,000 cfsthe site was a clear side channel with
apparent upwelling groundwater;the site was put into
Response Category 2 (see Figure E.3.2.45).If at 23,000
cfs,another site was considered to be a turbid side
channel,and at 16,000 cfs it has remained a turbid side
channel;the site was put into Response Category 4 (see
Figure E.3.2.45).A complete description of this process
and the results of the analysis is presented in EWT&A and
AEIDC (1985).
In addition to determining the response behavior of specific
habitat areas,certain other characteristics of the sites
were used to place the sites in relatively homogenous
representative groups.A primary factor considered in the
evaluation of the sites was the mainstemdischarge required
to breach the upstream ends of defined channels.For
example,defined channels which only convey mainstem water
at discharges greater than 20,000 cfs and are breached at
discharges less than 35,000 cfs were put into one group.
Those channels for which the upstream ends become breached
between 5,100 and 20,000 cfs were placed in another group
and.cthose __whi.ch _conv.ey__mainstem_di scharcge~and~-are...consi dered
to be side channels at less .than 5,100 cfs were placed in
another group.Other considerations used for placement into
a particular group included presence or absence of groundwa-
ter upwelling,length to width ratios,cross sectional
shape,mean channel water velocity,substrate composition
andpool-to-riffle ratios (EWT&A and AEIDC 1985).
Based on these considerations,ten groups of sites were
....··Tdeiifified~with···an ···siEeswiElliiia-groiiph-,iving·Similar
-~_.~~-_._------~_.-------------..------"---------res pons es-to---Clfahges --i-ff-fl-ow and-cnannel-cna ra c t e t-i-s"ti-cs -~-
The ten groups are presented in Tables E.3.2.30 through
E.3.2.39.Brief descriptions of the groups and the specific
sites included in the groups are presented with the tables.
The sites are identified by river mile and their occurrence
on the left or right side of the mainstem looking upstream.
A complete description··of the dev~lopment-ofthe
representative groups is presented in EWT&A and AEIDC
(1985)•
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851021 E-3-2-78
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(c)Principal Habitat/Species Combinations (***)
Although all salmon species and resident species inhabit the
Middle River during some period during the year,only a
few species utilize areas which are sensitive to changes
in mainstem flow.Discussion of both the sensitivity of the
habitat areas to mainstem flow change and the occurrence and
distribution of the fish species have been presented
previously in Sections.2.2.1 and 2.2.2 and Tables
E.3.2.26 and E.3.2.28,respectively and are summarized in
Table E.3.2.40.
Several observations can be drawn from the habitat uses
summarized in Table E.3.2.28.First,tributary habitat LS
the habitat type used most commonly by the species
inhabiting the middle river.Sockeye salmon and burbot are
the only species that do not use tributaries extensively for
important life history phases.SecondLy,the resident
species make little use of side channel,side slough or
·upland slough habitats;whereas the anadromous salmon
frequently use these habitats.The most common use of the
mainstem habitat type is for migration and movement although
resident species also overwinter in the mainstem (HE
1985a).
Habitat requirements associated with migration and movement
are less critical and restrictive than for the other life
history categories (ADF&G 1984h,1984c,1985b,1985c).
Suitable depths and velocities exist over a broad range of"
mainstem flows.Flow requirements to satisfy the more
critical needs of rearing and spawning/incubation will also
satisfy the habitat needs for migration.Therefore,habitat
requirements for rearing and spawning/incubation were
emphasized for the remainder of the analysis.
The four sensitive habitat types from Table E.3.2.28
(MS=mainstem,SC=side channel,TM=tributary mouth and
SS=side slough)were selected for comparison based on their
use for rearing and spawning/incubation (See Table
E.3.2.40).
Mainstem habitat (MS)is used mostly for rearing,especially
overwintering (ADF&G 1984c,1985c).Use of the mainstem by
chum juveniles is transient and short-term during their
downstream movement to Cook Inlet (ADF&G 1984c,1985c).The
major use of mainstem habitat by Arctic grayling,rainbow
trout and Dolly Varden is for overwintering,although the
populations of all the resident species in the Middle River,
including burbot,are characterized as low density (ADF&G
1983m,1984c).
851021 E-3-2-79
851021
Arctic grayling and rainbow trout use tributary mouth
habitat (TM)for rearing during the ice-free seasons.Use
by rainbow is transient,occurring mostly in the late summer
and fall (ADF&G 1983m,1984c).
Side channel habitat (SC)is used by chinook salmon for
rearing and by chum salmon for spawning (ADF&G 1983a,1983m,
1984h,1984c,1985b).The chum salmon spawning is limited
to sites with sufficient upwelling and accounts for
approximately five percent of the total chum spawning in the
middle river basin (ADF&G 1983b,k,n,1984h).
Chinook juveniles rear in side channels through most of the
summer and early fall (ADF&G 1984c).The use of this
habitat appears to be important to chinook produciton in the
Middle River.Therefore,chinook rearing in side channels
was selected as one of the critical uses of a sensitive
habitat for primary consideratiQn in developing environmen-
tal flow requirements (HE-1985a).Side channels are
generally represented in Representative Groups 3,4,and 6.
(EWT&A and AEIDC 1985).
Side Slough habitats (SS)are used by salmon for both
rearing and spawning/incubation.The chinook salmon rearing
in side sloughs during the ice-free season is a lesser
component of the total population than those rearing in side
channels.Flow requirements to maintain side channel
habitat would also serve chinook rearing in side sloughs.
----,Environment'a1~-flow··cases~,des·igned~to-pl:'otect~chi,nookrea ring
in side channels should also provide for overwintering in
side sloughs since,for the most part,the same fish use
both habitats (ADF&G 1985a).
Chum and sockeye salmon use side sloughs for both spawning
and rearing.Sockeye use of this habitat is so similar to
chum,in time and.location~that their habitat needs can be
_,Rt:~rv:i.cl.~.gQy_c:()JJ,C:~!l_t.!'-~t:i,!lg(),!l_t;h~,_!Il,Q.~~tl'l:>1.1'l1:~ant ...chum ...salmon.
Both species use side sloughs for short term,inItIal rear-.
ing prior to outmigra'tion to Cook Inlet 'or movement to
another habitat type.Chum salmon utilize side sloughs
extensively for spawning.This is the most intensive use of
a sensitive habitat in the middle river for spawning.
Therefore,chum salmon spawning in side sloughs was selected
as another critical use of a sensitive habitat for develop-
ment of'envi rot1trfental"flow 'cases"'(HE'-1985ah .,.Side slough
habitats are generally represented in Representative G:roup 2
(EWT&Aand'AEl:r5C T9·85T •.
In conclusion,two principal species/habitat combinations
were selected to evaluate the response of habitat to changes
E-3-2-80
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,)
(
851021
(d)
in flow and the subsequent effects on fish.These species/-
habitat combinations are juvenile chinook salmon rearing in
side channel habitats during the summer,and adult chum
salmon spawning in side slough habitat during the summer and
chum embryo incubation during early winter months.Juvenile
chinook overwintering in side sloughs will also be discussed
to a greater extent than other species habitat combinations.
These two species/habitat combinations form the focus of the
flow selection and mitigation planning process (see Exhibit
B and Exhibit E,Chapter 2,Section 3).Effects of an
altered flow regime on other species will also be
discussed.
Quantification of Habitat Response to Flow Changes (***)
The fourth step is describing the response of habitat to
discharge delineated in the introduction to this section is
to quantify the response of habitat.This is accomplished
in three steps.First,the range of physical habitat
conditions that are suitab1e for each fish species must be
described.Second,the range of habitat conditions present
in a defined area at various flows must be described.
Third,the proportion of the total wetted surface area
within a defined area containing suitable habitat conditions
for each species through a range of mainstem flows must be
calculated.
(i)Development of Suitability Criteria (***)
Two basic methods may be employed to describe the
particular ranges of habitat conditions that are
used by fish.These are determination of preference
criteria or determination of suitability criteria.
Preference criteria is developed by comparing the
range of available habitat conditions with the ranges
utilized by the particular species.Suitabilility
criteria are developed principally by defining the
range of habitat conditions utilized by the species
of interest.For juvenile chinook and spawning chum
salmon,suitability criteria for principal habitat
characteristics were developed (ADF&G 1983m,
1983k,1983n,1984c,1984b).
Juvenile chinook suitability criteria were developed
for depth,velocity and object cover by measuring
these characteristics in areas where juvenile chinook
were present (ADF&G 1983m,1984c).During the
investigations it was noted that there was some
distinction between the ranges of water depths,
velocities and object cover used in clearwater
E-3-2-81
851021
and those used in turbid water.Hence,two sets of
suitability criteria were developed for juvenile
chinook rearing (ADF&G 1984c;EWTA and WCC 1985).
These criteria are presented in tabular and graphical
form in Figures E.3.2.45 and E.3.2.46,respectively.
Cover suitability criteria are depicted graphically
in Figure E.3.2.47 and in tabular form in Table
E.3.2.41.Detailed descriptions of the development
of these criteria are presented in ADF&G (1984c)and
EWT&A and WCC (1985).
A similar set of suitability criteria were developed
for chum salmon spawning habitat.The prime
consideration in this development was the presence or
absence of groundwater upwelling.Throughout the
field program,chum salmon were observed to spawn
only in areas where groundwater upwelling was present
(ADF&G 1983k, 1983n,1984b).Due to the difficulty
in determining the areal extent and the rate of
groundwater1upwelling as it influenced the selection
of spawning sites by chum,a simple binary criterion
was developed (ADF&G 1983r1,1984bL The suitability
index for the presence of groundwater is 1 and for
the absence of groundwater is O.In areas where
groundwater upwelling is present,suitability
criteria in terms of water depth,water velocity and
substrate composition were developed.No difference
in the ranges of those characteristics was observed
between clearwater·and-turbid water conditions.
Therefore only a single set of criteria was developed
and are presented in Figures E.3.2.49,E.3.2.50 and
E.3.2.51,respectively (ADF&G 1984b).
The ranges of depth,velocity and substrate
composition determined to be suitable for chum salmon
spawning in mainstem affected areas of the Middle
Rive r ...(i.e.exclus ive.of ..tri but.ar_iesJar:~__p:r:e~'Lented._
in graphical and tabular form.The p.t"~senceof
groundwater upwelling is incorporated in the
substrate suitability criterion (ADF&G 1983k,1983n,
1984b;EWT&A and WCC 1985).
(ii)Determination of the Range of Habitat Conditions
Available (***)
For the middle SusitnaRiver,two variations of the
-instI:ealllFiow-Group (rFG)hydraulic models,the
IFG-4 hydraulic model and the IFG-2 hydraulic model
(BoVee and Milhous 1978,Bovee 1982)were used to
determine the ranges of conditions available within
E-3-2-82
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1
·OJ
851021
the sites for use by juvenile chinook salmon and
spawning chum salmon.Fifteen site~were selected to
describe the available ranges of habitat conditions
within the sites using the IFG models.(ADF&G 1983n,
1984b;EWT&A 1985c).Sites for which IFG hydraulic
models were developed are identified on the list of
sites within the 10 representative groups (Tables
E.3.2.30 through E.3.2.39).
Two additional types of models were developed for
other sites within the Middle River.The habitat
simulation model developed by ADF&G (1983m,1983n,
1984c),referred to as the RJHAB Model,uses field
data directly in evaluating the available habitat for
juvenile salmon r~aring.A direct input variation of
the IFG Model (DlHAB)which also uses field
hydraulic data directly was developed by.EWT&A
(1985c).Neither of these models simulates hydraulic
habitat conditions between the discharges at which
the data were collected.The habitat conditions at
set intervening flows are interpolated linearly.A
total of 6 sites were modelled using the RJHAB Model
and a total of 12 sites were modelled using the DIHAB
variation of the IFG Model.Sites for which RJHAB
and DlHAB Models were developed are identified in
Tables E.3.2.30 through E.3.2.39.
Each of the IFG models was calibrated using physical
habitat data collected.at the model sites at 3 to 5
different site flows.Outputs of the hydraulic
models include water surface area of the sites,and
distributions of water depths,water velocities and
substrate composition throughout the modelled sites
at each calibration site flow and specified
intervening site flows (ADF&G 1984b;EWT&A
1985c).The physical habitat characteristics versus
site flows were then translated to physical habitat
characteristics versus mainstem flows from
concurrent measurements of site flow and mainstem
discharge at the USGS Gold Creek Gaging Station.
Mainstem versus site flow relationships are presented
in (ADF&G 1983k,1984i).Specific procedures used
for hydraulic model calibrations and verification are
presented in ADF&G (1984b).
(iii)Habitat Response Curves (***)
The evaluation of the response of habitat for
juvenile chinook rearing and chum spawning is
E-3-2-83
851021
accomplished by determining the proportions of the
total water surface of the areas within the 'modeled
sites which have suitable physical habitat
characteristics.The apportionment of the total
surface area which contains suitable habitat is
accomplished by multiplying the wetted surface areas
of individual cells within the model site by the
suitabilities with respect to depth,velocity and
cover as substrate.This apportionment is generally
accomplished for the IFG Model site through the
HABTAT Model developed by the Instream Flow Group
(Boves 1982).The ,surface areas of the cells are
miltiplied by the suitabilities of the depth velocity
and cover or substrate present in the cells.The
output from this model is presented in terms of
Weighted Useable Area (WUA)per 1,000 ft of stream
for a range of flows appropriate to the "analysis.
Also,output from the model includes the gross water
surface area per 1,000 ft of stream.
Usually,the WUA per 1,000 ft is used directly for
the evaluatio11.of ha.bita.t response to flow.However,
because the modelled sites in the Susitna River
represent a variety of habitat types (Le.10
Representative Groups),an index or proportion of the
total surface area which contains suitable
"conditions was estimated.This proportion is
determined by dividing the WUA/1,000 ft by the total
·-wettE!"d~surface-area-!l,OOO "ft-;--These ratios are
multiplied by 1,000 sq.ft.to give a number that is
more easily int~rpreted as the WUA per 1,000 sq.ft.
of water surface area.
Habitat response curves for juvenile chinook rearing
were developed for 14 of the IFG Model sites (ADF&G
1984c,EWT&A 1985c).Six additional sites were
modelledus.ing..the.RJHABMo.deLdeveLopedby-ADE&G
._(l984c)..!..The RJHABModel is a direct in~ut typ~_.....
model in which the surface areas for individual cells
within the model site are multiplied by the suitabi-
lity factors and the cells WUA's summed.As with the
IFG Model,the RJHAB Models provide WUA's and total
surface areas.However,these are presented in terms
of the total length of the model site and must be
standardized to 1,000 ft of length or the proportions
can be calculated directly from'the ouput.One of
the s:i.iliJHABModeHrig sites wasaIsomodefed with
the IFGModel for comparison.Habitat Response
curves for juvenile chinook salmon rearing for 20
sites are presented in tabular form in Table E.3.2.42
E-3-2-84
}
j
and are depicted graphically in Figure E.3.2.52.
Sites for which IFG and RJHAB Models were developed
are identified in Tables E.3.2.30 through E.3.2.39.
Habitat response curves for chum salmon spawning
areas were taken directly from the IFG and DlHAB
model results without standardization to 1,000 ft of
stream length or to WUA per 1,000 sq.ft.of surface
area.Six IFG models and 12 DIHAB models were
developed at sites used by chum salmon for spawning.
Results of these models,in terms of the total WUA
for chum spawning at the sites,are presented in
Table E.3.2.43 and are depicted graphically in Figure
E.3.2.53.
The sites used by chum salmon for spawning are
located throughout the middle river and.each can be
placed in one of the Representative Groups,which are
identified in the table.In addition to the use of
all modelled sites for evaluating chum spawning
habitat response to flow,standardization of the
model results to WUA/1,000 sq.ft.,as described
above for juvenile chinook rearing habitat,was done
for the IFG model and DlHAB sites included in
Representative groups 2,3 and 4.These standardized
results are presented in Table E.3.2.44_and ar.e
depicted in Figures E.3.2.54.
(e)Habitat Response Curves for Non-Modeled Sites (***)
A general characteristic of these curves response for
modeled sites is that the WUA relationship is at its
maximum at discharges above those required to breach the
upstream ends of the sites.At discharges less than
breaching flows,WUA remains relatively constant at all
mainstem flows since flow in the side is relatively
constant.At extremely high mainstem discharges (in excess
of approximately 30,000 cfs)both chinook rearing habitat
and chum spawning habitat decreases rapidly due mostly to
increases in water velocity.Another general characteristic
is that the shapes of the curves are affected by the
particular morphological or structural characteristics of
the sites.Because of generally uniform characteristics of
the curves,it is possible to adjust the habitat response
curves for the modeled sites to represent the response
curves expected in the non-modeled sites (EWT&A and AEIDC
1985,EWT&A 1985a).
Adjustment of the habitat response curves of modeled sites
for representing non-modeled sites in the representative
851021 E-3-2-85
group is accomplished in two steps.First,the response
curve of the modeled site is shifted to higher or lOwer
mainstem discharges according to the breaching discharges
for the modeled and non-modeled site.For example,if the
breaching flow for a modeled site is 12,000 cfs and the
breaching flow for a non-modeled site is 14,000 cfs;2,000
cfs is added to the flow coordinates for the modeled sites
to give the flow coordinates for the non-modeled site.This
shifting of the curve is demonstrated in Figure
E.3.2.55.
Although the general structural and morphological
characteristics are similar for all sites within a
representative group,differences between the sites will
result in some difference between the habitat values of
modeled and non-modeled sites for each mainstem discharge.
The second adjustment to the habitat response curves for
modeled sites to represent non-modeled sites is to multiply
the habitat values of modeled sites by a ratio of an index
of the the structural characteristics for the non-modeled
sites to an index of the structural characteristics of the.
modeled sit::es.Toaccomplish-this~aSttuctutalHabitat
Index (SHI)for each site was developed (EWTA and AEIDC
1985).The SHI is based on channel characteristics such as:
dominant cover-type/percent cover,channel geometry,
substrate sizel substrate embeddednessand s·tr:eamside
vegetation.The development of the SHI for each site is
described inEWTA a.ndAEI~C (l985).The SHI's for all sites
are presentea-in--Taoles-E-.3-:-2 :30-tnr0i1gh~E';-3;2~-39~In some
cases,more than one modeled site is included in a
representative group.Within the group,the range of SHI's
is such that non-modeled arid modeled sites can be accumula-
ted into sub-grOups with silll ilar SHI's •..The ratio of the
SHIs for the non-modeled sites to·the SHI for the modeled
sites are~hen calculated and the habitat coordinates of the
habitat resPQnse curves for the modeled sites are multiplied
·-by-the-ratios-to....produ ce-.the-hab.itat values__foJ."_t_he
-------------------non""mode.lecL_si.t.e._This.-p-r-o_c_ess is depicted in Figure
E.3.2.55.A detailed discussion of the adjustnl;;nts-of--'
modeled site habitat response curves fot non-modeled sites
is presented in EWTA (1985a).
Once habitat response curves (in terms of WUA/1000 sq ft vs
flow)arliadevelopedfor each specific area,the total WUA
fore'achslt::e 18 ob-tained-bYiriijlt:i.pJying~lj:E:~WUA/1000 sq ft
at each flow by the total wetted surface atea at each flow.
This is accomplished by first--di\i1.clTni-the·~WtfA/I000 sq ft by
1000 sCI,ft and then multiplying by the wetted surface areas.
The WUA's at each flow are then added to obtain total WUA's
for each group.
J
j
851021 E-3-2-86
r
851021
The chinook rearing habitat response curves for nine
representati ve groups are presented in Table E.3.2".45 and
Figure E.3.2.56.By adding these curves together a total
habitat response curve for middle river chinook rearing is
generated.The total habitat response curve is presented in
tabular form in Table E.3.2.46 and is depicted in Figure
E.3.2.57.Perusal of the habitat response curves for each
of the representative groups indicates that some of the
groups are more sensitive to discharge than others.The
most sensitive groups appear to be Representative Groups 2,
3 and 4,Sites included in Representatives Group 2 appear
relatively sensitive to discharge,with peak values of WUA
at mainstem discharges greater than 20,000 cfs.This
corresponds to the fact that all of these sites breach at
mainstem discharges between 20,000 cfs and 35,000 cfs (see
Table E.3.2.31).These sites are generally considered to be
side sloughs.Juvenile chinook are generally not found in
these sites when mainstem discharge is less than that
required for breaching (ADF&G 1984 Rpt 2).However,
juveniles are found in the sites when the upper ends are
breached.Sites included in Representative Group 3
generally breach at mainstem flows between 5,000 and 20,000
cfs.These sites have been observed to be utilized by
juvenile chinook for rearing more extensively than any other
group of sites affected by mainstem discharge.Sites
included in Representative Group 4 are generally large side
channels which breach at mainstem discharges less than 5,100
cfs.Juvenile chinook have been observed in these sites to
some extent.It is expected that these sites will provide
significant rearing habitat under project conditions because
peak habitat values are associated with discharges between
8,000 and 12,000 cfs which are approximately in the range of
discharges expected during project operation (see Section
E.3.3 below).Taken as a subset of the total habitat
available for juvenile chinook rearing,Representative
Groups 2,3 and 4 are used in the analysis to depict the
effects of replacement of habitat in one group with habitat
in other groups.The sub total habitat areas in these three
representative groups vs flow are presented in Table
E.3.2.46 and are depicted graphically in Figure E.3.2.58.
A total habitat response curve for chum salmon spawning was
developed simply by adding the WUA's obtained for each of
the IFG and DIHAB models presented in Table E.3.2.43.
Extrapolation to non-modeled sites was not considered
necessary for chum spawning habitat because the modeled
sites include the spawning area for approximately 90 percent
of the chum salmon estimated to spawn in habitat areas
affected by mainstem discharge under existing conditions.A
principal characteristic of chum spawning area is the
E-3-2-87
presence of groundwater upwelling in the site (ADF&G 1983k,
1983n,1984b).Since the presence or areal extent-of
groundwater upwelling is primarily dependent upon
characteristics of the alluvium,upwelling areas are not
expected to change significantly with changes in discharge.
Therefore,changes in mainstem discharge which are
attributable to project operation will directly affect the
habitat availability for chum spawning and any lost area is
not expected to be replaced with suitable habitat at other
locations without mitigation measures.The total habitat
area response curve for chum salmon spawning is presented in
tabular form in Table E.3.2.47 and is depicted graphically
in Figure E.3.2.59.
However,in order to be consistent with the analysis
performed for the response of juvenile chinook rearing
habitat to discharge,the chum spawning habitat area
response to mainstem discharge was also developed for all of
the modeled and non~modeled sites included in Representative
Groups 2,3,and 4.Although the extrapolation of the
modeled sites to non-modeled sites for chum spawning is not
necessary>as explained above,the extrapolation process was
conduc:ted for these three groups of sites since each group
is characterized as having groundwater upwelling present in
the site and demonstrate a r:elatively high degree of
sensitivity to mainstem discharge.
In this analysis,it must be assumed that the groundwater
..._~-upwell ing"-wi thin the-non""modeled ....sLtes~is-proport iona lly
similar to the modeled sites with respect to both the areal
extent and the distribution of the upwelling.Ext'rapolation
of the IFG amd DIHAB modeled sites to the respective
non-modeled sites was performed in the manner described for
the chinook rearing habitat area.The habitat area response
curves for the Representative Groups are presented in Table
E.3.2.48 and are depicted graphically in Figures E.3.2.60
through E.3.2.62.The total habitat are~response curve,
Tnclud:i.ns"arr of··Ehe···IFG""·Il1()deI ed"and·non=mocfeIed"sitei"iti
---.the three groups,fsalso presentea-i"n-TaJ51aE:3"~2~48-and-is
depicted graphically in Figure E.3.2.63.
(f)Habitat Response to Natural Flow Regime ***
As indicated in the habitat area response curves
·presented"in··the previous'section,·the··availabi Ii ty of
chinook rearing ha1>.itat a.nd chum spawning habita.t varies
with 11lai lis tern di scha.tg·es~The·tdtal"h:abi:tat areas tend td
remain relatively high over a relatively broad range of
mainstem discharges.Because the fish are able to select
suitable habitats from the array of habitats in the river,
·1
851021 E-3-2-88
1
I
851021
it is appropriate to evaluate the total habitat availability
through time using the total habitat area response -curves
for chinook rearing (Table E.3.2.46)and chum spawning
(Table E.3.2.47 and E.3.2.49).
The availability of total habitat area through time may be
evaluated by translating the average weekly discharges at
Gold Creek into total average weekly habitat areas.Hence,
for every average weekly discharge in the 34 years of
historic discharge record,equivalent habitat areas are
derived from the habitat area response curves.Based upon
these translations for chinook rearing and chum spawning,
time series and frequency analyses may be performed.Time
series analysis consists of plotting the average weekly
habitat areas sequentially through the 34_years of record.
The frequency analysis consists of determining the habitat
values which are equalled or exceeded 90,50 and 10 percent
of the time using the weekly habitat values derived from the
average weekly flows under the natural flow regime.Results
of these ana1yses~for chinook rearing and chum spawning
habitats are presented in the following sections.
(i)Chinook Salmon Juvenile Rearing Habitats (***)
The evaluation of the response of juvenile chinook
rearing habitats to the natural flow regime consists
of determining the total area available in the
Representative Groups that have suitable depth,
velocity and cover characteristics.The habitat
response curves presented in Section E.3.2.2.3 for
juvenile chinook rearing were developed for the
open~wate~'season.These curves are not valid for
winter conditions,since the juveniles redistribute
themselves into side slough-type habitats that
generally have warmer water derived from groundwater
upwelling sources.Instream hydraulics during winter
months are greatly modified by ice processes.
Therefore,hydraulic models developed for open water
channels are invalidated with the formation of an ice
cover.In addition,the behavior of the fish and
their ability to maintain position is dependent on
the temperature of the water.Thus,the suitability
criteria are not valid for water temperatures less
than approximately 4°c.As a consequence,the time
series and frequency analyses presented below are
conducted for the period June through September.
E-3-2-89
851021
Frequency Analysis and Discussion (*)
Using the 34 years of recorded weekly average dis-
charge at Gold Creek and the habitat area response
curve for juvenile chinook rearing,the median
(50 percent exceedance value)total chinook
rearing habitat area in the nine representative
groups of sites ranges from approximately
5,000,000 to approximately 7,000,000 sq.ft.
through the summer months.Habitat areas
generally decrease near the end of the summer as
discharge in the river decreases.Because
discharge in the river can vary substantially
through the summer period,the total habitat area
also varies considerably.The median (50 percent)
habitat areas for each week through the summer
together with the habitat areas which are equalled
or exceeded 90 percent and 10 percent Df the time
are presented in Table E.3.2.49 and are depicted
-graphically in Figure E.3.2.64.The lower habitat
values,i.e.the 90 percent exceedance values,
are associated with both extremely low mainstem
discharge and with relatively high mainstem
discharge .as shown in Figure E.3.2.64.The 10
percent exceedance value is clos~ly associated
with the optimum flow providing the maximum
habitat values.The 10 percent exceedance values
of habitat area tend to be associated with those
-~--~~ftowso-co-rresp-onding~to-the-'-Peakhabitat va-lues-
presented in Figure E.3.2.64.Hence,the 90 and
10 percent exceedance habitat values do not
correspond to the 90 and 10 percent exceedance
flow values.Because the natural flow regime is
not regulated either at the high or low
discharges,the range of habitat area available
through time tends to be large.Hence,chinook
..reari ng ..habit a t.du;t'iJ:1,g_t_hC:L_SJ~.mm~_;t'_J,md~_~.th~.
..~_.natural_flow regime.is C:haracterized.by high
variation from week to week and from ·year -t-o·----
year.
A similar relationship is observed for the subset
of the total chinook rearing habitat response
curves including only Representative Groups 2,3
and4(TaDleE~3~2.46aridFigtire E.3.2.58).Total
habitat area for juvenile chinook in the three
representa.t:£'vegroups generally ranges from
approximately 2,000,000 sq ft to approximately
5,000,000 sq ft through the summer months.The
range of habitat values in these group through the
E-3-2-90
l
-l
:1
851021
summer weeks represented by the 90,50 and 10
percent exceedance values for the 34 year'of
record are presented in Table E.3.2.50 and are
depicted graphically in Figure E.3.2.65.
Unlike the habitat values using the response curve
for all site~,the median chinook rearing habitat
areas gradually increase through the summer with
the most noticeable increase observed in August
and September (weeks 32-39)which is associated
with the 'gradual decrease in discharge near the
end of the summer.the increase in habitat area
is associated with the replacement of habitat area
in Representative Groups 2 and 3 by the habitat
areas in Representative Group 3 and 4.This is
indicated by habitat response curves for the
respective groups presented in Figure E.3.2.56.
During the middle of the summer,chinook rearing
habitat in Representative Groups 2,3 and 4
remains relatively stable from year to year.
Considerably more variation is apparent in June,
August and September as indicated by the
difference between the 90 and 10 percent
exceedance values in Figu~e E.3.2.65.
(ii)Chum Salmon 'Spawning and Incubation Habitats (*)
The evaluation of the response of chum salmon
spawning and incubation habitats to changes in
discharge in the mainstem consists of three
principal elements:First,flow must be sufficient
for the adult salmon to gain access to the spawning
areas.Second,flow in the spawning habitats must be
sufficient to provide suitable conditions for
spawning activities as described in Section
2.2.3.d.i,that is,the habitats must have suitable
water depth,water velocity,and substrates and
groundwater upwelling must be present.Third,the
sites must retain suitable depth,velocity and
upwelling through the winter so that salmon embryos
can survive and develop to the juvenile stage.
-Access Conditions vs.Flow (*)
The evaluation of conditions necessary for chum
salmon to gain access to spawning areas is a key
step in the overall evaluation of the effects of the
proposed project on existing populations and their
E-3-2-9l
851021
habitats.Approximately 15-25 percent of the chum
salmon (approximately 5,000 to 10,000 fish}which
enter the Devil Canyon to Talkeetna reach of the
Susitna River spawn in side sloughs and side
channels (ADF&G 1984h,1985b).
Side sloughs and side channels are overflow channels
of the mainstem which convey turbid mainstem water
when mainstem discharge and,therefore,stage is
sufficiently great to breach the upstream ends of the
channels.Discharges of sufficient magnitude to
breach the channels generally occur during the
summer,open water months.When mainstem discharge
is lower,the upstream ends of the channels are not
breached and the channels are similar to small
tributaries which convey clear water derived from
local surface runoff,small tributaries and upwelling
groundwater.During periods when mainstem discharge
is not sufficient to breach the channels,side slough
(EWT&A 1984)dischargesranlie from about 1-2 cfs to
more than 10 cfs.The actual slough dischage at any
given time is dependent upon whether or not small
tributaries enter the slough,the amount of local
precipitation,and the amount of groundwater
upwelling.When the 'upstream ends of the sloughs are
overtopped,slough discharges range upward of several
hundred cubic feet per second (ADF&G 1983k,1984i,
R&M 1985b).
The ability of chum salmon to gain access to spawning
areas within specific sites is dependent upon the
depth of water in the channels.In general,the
shallower the·water,the more difficult the passage
conditions ar~for movement of salmon through.the
reach (ADF&G 19851).
ReachesCof"aslough in which the water depths are
-oc"ca"shmally-stfffrci-e"n:tly"slral"low-to'restrict··
·movement-of-fi~sh-a·re-termed-pa"ssage-reaches.".
Generally,passage reaches are located in riffle
areas within the sloughs when slough discharge is
relatively low (i.e.the sloughs are not breached).
For most passage reaches within sloughs,the depth of
water is dependent upon the slough discharge derived
from local surface runoff or groundwater upwelling.
...For passage:reaches "'loca ted near the ··downs·tream ends
of the sloughs,water depth is influenced not only by
slough discharge,but also by mainstem backwater.
The backwater effect on the depth of water in a given
E-3-2-92
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851021
passage reach is evident when the water surface
elevation of the mainstem near the slough mouth is
greater than the water surface elevation in the
passage reach.Hence,suitable access conditions ~n
passage reaches are primarily dependent upon the
local slough discharge.However,at certain
locations,the passage reach can be influenced by
mainstem discharge and associated water surface
elevation.When the sloughs are breached,discharge
in the channel is greatly increased and provides
access.
To compare conditions at a passage reach at various
mainstem discharges,ADF&G established three passage
condition categories representing .degrees of
difficulty for salmon gaining access upstream of the
passage reach.These three conditions are termed:
unsuccessful,successful with difficulty and
successful (ADF&G 19851).These conditions
correspond to the terms acute,restricted and
unrestricted,respectively (ADF&G 1983k,1983n)and:
described in the original License Application (APA
1983b).The three passage conditions are
distinguished by threshold depths in the passage
reach and their corresponding mainstem,local
discharges or combinations of mainst.e1lli and local
discharges.Early analyses of passage depths which
distinguish the passage conditions resulted in the
definition of threshold passage depths which are
greater for longer reaches (Trihey 1982d,ADF&G
1983k,1983n,1984r).However,further refinement of
the analysis and the incorporation of observational
data indicate that chum salmon passage criteria are
most sensitive to depth (ADF&G 19851).The depth
criteria which distinguishes unsuccessful passage
conditions from successful-with-difficulty and
successful-with-difficulty from successful are
presented in Figure E.3.2.66.The threshold depth
criteria derived by ADF&G are similar to those
derived by Thompson (1972).
Detailed analyses of passage reaches in most sloughs
in the middle reach of the Susitna River have been
conducted to determine mainstem and/or local
discharges needed to meet the threshold depths
described in Figure E.3.2.66.Local flow required to
provide successful-with-difficulty and successful
access conditions through the various reaches are
provided in Table E.3.2.5l.Mainstem discharges
required to meet the threshold depths in the passage
E-3-2-93
851021
reaches located near the mouth of the sloughs are
also presented in Table E.3.2.5l.
Perusal of the mainstem discharges required to
provide suitable access conditions at some passage
reaches presented in Table E.3.2.5l indicate that the
required mainstem discharges are considerably greater
than the median discharges observed in the river
during the chum spawning period (August-September)
(Exhibit E Chapter 2).There are two possible
explanations for the apparent high mainstem discharge
needs •
The first consideration is that the results for local
flow and mainstem discharge needs presented in Table
E~3.2.51 were derived independently of each other.
That is,the local discharge which provides suitable
access conditions at passage reaches were derived
without considering the backwater effect of the
mainstem.Similarly,the mainstem discharge which
has sufficient backwater to provide suitable.depths
through the passage'reaches'were derived without
considering the cOlltribution of local flow.
Local flow is derived from both local surface runoff
and from groundwater upw,elling..Local surface runoff
tends to be episodical in nature since it is closely
associated with the precipitation patterns in the
clocal~··area~'(R&Mc@85b}.~c-G~oundwatet'upwe,Uing.,
on the other hand tends to be more constant through
time with some.fluctuation in response to mainstem
stage (Exhibit E,chapter 2 Sections 2.4.4,and 4.1.2
(f)ii).B~cause groundwater upwelling rates can be
directly reLii:edi:o rnainstem'discharge,at least for
some sloughs,it is likely that sufficient discharge
ts available in the sloughs to provide sufficient
,QE!Rt:h.J:h!,().!J,gh .!'1~tl,Y,_QJ,.t:,hE!l'~.I3.I3~gE!.reaches at
discharges considerably less than that necessary to
'breach the u'pstream ends or that ."necessary to proviae-.....-----------.
sufficient depth due to backwater effects only (HE
1984d)•
A second consideration which must be accounted for in
the determination of maitistem discharge necessary to
'providesuitable'access'conditions into thesioughs
is observations of adult chum salmon in sloughs
relative'tothe ..average"daiTy'ai-scharges ill the
river.Average daily discharge in the middle Susitna
River in 1982 ranged between 13,000 cfs and 18,000
cfs from August 1 until September 15 (USGS 1983).
E-3-2-94
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851021
Periodic counts of adult chum salmon in the various
sloughs during this period indicate that chum salmon
did gain access to sloughs when mainstem discharges
were considerably lower than many of the threshold
values presented in Table E.3.2.51 (ADF&G 1983a).
The conclusion drawn from this,then,is that the
threshold discharges presented in Table
E.3.2.51 error in favor of the fish resource.
However,they do provide a worst case for analyses of
impacts resulting from the altered flow regime on
access conditions for chum salmon into slough
spawning habitats.
-Frequency Analysis of Chum Spawning Habitat Area (*)
The second analytical step in the evaluation of chum
spawning habitat is the estimation of the total
amount of spawning habitat area given the range of
mainstem discharges that occur during the spawning
period.As stated in Section 2.2.1.a.iv,chum salmon
spawn in the period August through September each
year.Using the 34 years of record of average weekly
discharges during this period and the chum spawning
habitat area response curve presented in Table
E.3.2.47 and Figure E.3.2.59,the range of habitat
area during each week of the spawning period was
determined.
Given the 34 years of record,the median habitat area
available in the sites used extensively by chum and
included in the modelled sites for each week in the
spawning period ranges from approximately 74,000 sq.
ft.at the beginning of August to approximately
76,000 sq.ft.in the middle of September.The
decline in available habitat area at the end of
September corresponds to the general decline in
mainstem discharge through the period (See Exhibit E,
Chapter 2,Section 2.2).The total habitat area
available in each week ranges from less than 26,000
sq.ft.to more than 86,000 sq.ft.The median (50
percent)habitat area available for each week in the
34 years of discharge record as well as the habitat
areas equalled or exceeded 90 and 10 percent of the
time are presented in Table E.3.2.52 and are depicted
graphically in Figure E.3.2.67.
As shown in the table and figure for chum spawning
habitat areas,the range of habitat area can vary
considerably from week to week and from year to year.
A general characteristic,however,is that the total
E-3-2-95
habitat area available for spawning peaks during the
last week of August and the second week of September
which corresponds to during the peak of the chum
spawning period.
Evaluation of the chum spawning habitat area under
the natural flow regime was also conducted using the
spawning habitat area response curve obtained from
modeled and non~modeled sites in Representative
Groups 2,3 and 4 (Table E.3.2.48 and Figure
E.3.2.63).A frequency analysis using the
Representative Groups total habitat area response
curve was performed.Based on this analysis,the
median total habitat area is relatively constant
through the spawning period at approximately 840,000
sq.ft.of usable area.The results of this analysis
are presented in tabular form in Table E.3.2.53 and
graphic~lly in Figure E.3.2.63.The decline in the
estimated total habitat area corresponds to the
gradual decline in mainstem discharge during this
period under natural conditions.As discussed with
respect to the estimated spawning habitat areas for
the modeled sites,the total habitat areas in
Representative Groups 2,3 and 4 vary considerably
from week to week and from year to year.The large
difference in total habitat are~s between the values
presented in Table E.3.2.52 and those presented in
Table E.3.2.53 is due to the fact that the Repsenta-
------~~~----~--tiveGroups-inc1:ude-many ·more~-si·tes ··and-,-therefore,
much ~ore surface area,than that contained only in
the modeled sites.By indicating the potential
spawning areas in the non-modeled (and presently
non-utilized sites),the peak habitat area
availability,observed for the utilized sites during
the first two weeks of September,is not evident.
-Fl:'~q~~!l~Y A!lI:!.JY·f;if;.Q[.Jil:!.bit:aJ;.....Al:'~I:!.Avl:!.:i.la.1:>l~fQ:r:
......__..._.__Incubation of Chum Embryos (*)
The third analytical step in the evaluation of chum
salmon habitats affected bymainstem discharge is
the determination of suitable conditions for
incubation of the embryos.Incubation begins with
the deposition of the eggs during the spawning
period~Iri tliefevaluation,itcail be assumed that if
suitable conditions for spawning are maintained into
tllefticubaEi()-11 -pel:icld;eiiib·ryos win be able to
survive.This is not completely valid since embryo
development can occur when water depths and
velocities are less than those required for spawning.
1
851021 E-3-2-96
lII
However,analysis of the total area which remains
suitable for spawning,in lieu of ice processes
effects,provides a minimum estimate of the
incubation habitat availability.
Estimates of habitat area available for incubation
(in this case synonymous with spawning habitat area)
were derived for the period October through November,
discounting the effects of ice processes (see below).
Median habitat areas available in the modeled sites
under the natural flow regime for incubation for each
week in the October-November period are presented in
Table E.3.2.54 and are depicted graphically in Figure
E.3.2.68.Also presented in the table and figure are
the 90 percent probability of exceedance and the 10
percent probability of exceedance habitat areas.
As indicated in the table and.figure,h~itat area in
the incubation areas declines as discharge decreases
in the fall period prior to freeze-up the river.The
loss of habitat during this period,combined with the
potential for freezing of substrates (ADF&G 1983m,
1985a)leads to the conclusion that the embryo
populations are subject to high mortality rates due
to freezing and dessication of the spawning/
incubation areas.It is estimated that under the
natural flow regime,mortality of chum embryos is
approximately 80 to 85 percent in the middle river
(ADF&G 1984c,1985c).
A similar trend is observed for sites included in
Representative Groups 2,3 and 4.Results of the
~nlysis using the habitat area response curve for all
sites in the three respresentative groups (Figure
E.3.2.63)are presented in Table E.3.2.55 and Figure
E.3.2.70.
(g)Natural Ice Processes Effects on Fish Populations and Their
Habitats (***)
The analysis of the response of chinook rearing habitat area
and chum spawning/incubation habitat areas presented in
the previous sections are applicable only during the summer,
open-water season.In the Susitna River,habitat for the
fish is influenced by winter conditions for nearly seven
months of the year.During the winter months,the Susitna
River becomes covered with ice which changes many of the
hydraulic and hydrologic relationships present in the river
during the open-water season.In order to evaluate the
effects of the project throughout the entire year,it is
851021 E-3-2-97
then necessary to describe how ice processes affect the
mainstem and mainstem associated habitats under natural
conditions so that the effects of project operation during
winter months may be identified.
Natural ice processes in the middle reach of the Susitna
River consist of ice cover formation,maintenance of the ice
cover through the winter months and deterioration of the ice
cover in the spring.The formation of the ice cover in the
middle reach generally begins between early November to
mid-December and is complete between mid-December and
mid-January each year (R&M 1984,1985a).The ice cover is
maintained through the winter months with open water leads
developing along the margins and in peripheral areas of the
river.The process of ice cover deterioration begins in
mid-to late-March with increasing solar radiation and is
generally completed by mid-May (APA 1984f,HE 1984a,
1985a,1985f,1985i;R&M 1984,1985).A more detailed
description of natural ice processes is presented in Exhibit
E,Chapter 2,Section 2.3.2.
During the winter,resident fish and-juvenile salmon move
into areas of the river that reduce their exposure to the
physical hazards of cold water and freezing.Resident fish,
including rainbow trout and Arctic grayling,move from
tributary habitats into the mainstem of the river and move
to the.mouths of tributaries,side channels and sid"e sloughs
(ADF&G 1983e,1983m,1984c).Burbot maintain their posi-
tions.inthemainstem~anddo_not__mov.e_extensi:velJ~during the __
winter months (ADF&G 1983e,1983m,1984c).Coho salmon,
sockeye salmon and chinook salmon juveniles remain in
freshwater for at least one winter after emerging from the
spawning gravels.The juveniles move into areas protected
from freezing and dessication.Coho salmon generally remain
in deep pools of tributary streams or move into upland
slough habitats (ADF&G 1983m).Sockeye salmon are found
mos~often in side sloughs during the winter months (ADF&G
-19g-.3mr~cfiiiio6ksalmoii..overwiiifeiTiieifhe-r f rioiiEary or
-------=siaesI ougtlhalfna es-(ADF&"G-r9-83c)-:~-"-Uf-eliese-eliree ..spe~ci-es;--
chinook salmon tend to be the most abundant species in main-
stem-affected areas (ADF&G 1983m,1983n,1984c).
Salmon spawn in several habitats during the late summer.
Selection of sites for deposition of eggs by adult females
is based upon specific habitat -conditions--that,over the
C:0t1I::se oJ Elvo1 t1 t:!01la.I::yJ:listory ,have led.to the highest
probabilities of the embryos surviving-through the·winter
incubation period.The majority of salmon (approximately
60,000 fish)spawning in habitats associated with the middle
reach of the Susitna River utilize tributary habitats which
851021 E-3-2-98
are unaffected by the ice processes in the mainstem (ADF&G
1981b,1983a,1984h).Approximately 30 percent (5000 fish)
of the chum salmon spawning in the Middle River utilize side
channels and side sloughs (ADF&G 1983a,1984h).All of the
sockeye salmon (approximately 1500 fish)and less than 5
percent of the pink salmon (approximately 1500 fish)
spawning in the Middle River utilize side channels and side
sloughs (ADF&G 1983a,1984h).Since all three species
utilize similar habitat conditions for spawning (ADF&G
1983k,1983n,1984h),chum salmon are used as the focal
point for evaluating the effects of ice processes on egg
incubation because they are numerically dominant.
(i)Effects of Natural Ice Processes on
Resident Fish (***)
In general,ice processes in the Susitna River
adversely effect the survival of resident species
through the winter months.Rainbow trout,Arctic
grayling and burbot remain relatively inactive during1_'
I I the winter (ADF&G 1983e).
Burbot spawn during the winter (ADF&G 1983m,Morrow
1980).However,they tend to utilize areas with low
water velocities,protected from ice processes (ADF&G
1983e).
II
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851021
(ii)Effects of Natural Ice Processes on
Salmon Juveniles (***)
Juvenile chinook and sockeye salmon utilize areas
that are occasionally affected by mainstem flow and
ice processes.In side channels and side sloughs,
areas over and downstream from groundwater upwelling
have water temperatures which are greater than oDe
and may attain temperatures approaching 4 De (ADF&G
1983e).Mainstem water temperature,by contrast,is
near oDe from prior to ice cover formation until
breakup (R&M 1984,ADF&G 1983e).The behavior of the
fish during the winter indicates that the juveniles
overwinter in or near the substrates and remain
relatively inactive in areas receiving groundwater
upwelling (ADF&G 1983e,1983m,1984c;AEIDe 1984a,
1984b,1984c).
The survival of juvenile salmon in sloughs and side
channels is affected by the formation of border and
anchor ice,overtopping of the side sloughs and side
channels resulting from mainstem staging and
E-3-2-99
increased rates of groundwater upwelling due to
mainstem staging.
When border ice and anchor ice forms where juveniles
are located,they may freeze if they are trapped in
areas that later freeze.The potential for this is
unpredictable and highly dependent upon air tempera-
ture,depth of water in the pools and strength of
upwelling that may occur in the pool.
Overtopping of the upstream end of the sloughs or
side channels can cause water to be diverted through
the channels displacing juvenile salmon into mainstem
areas.At O°C,metabolic processes of the fish may
be sufficiently low to prevent them from maintaining
positions in even low water velocity areas.
Increased rates of upwelling associated with the
increased stage of the mainstem due to ice cover
formation probably contributes to the survival of
juvenile salmon in winter (ADF&G 1983e,1985a;APA
1984g;AEIDC 1984c,1984b).The groundwater
upwelling provides 2-4°C water temperatures in the
sloughs and side channels (ADF&G 1983e,1985a).The
upwelling also inhibits the formation of a complete
ice cover (R&M 1984,ADF&G 1984c).It,is assumed
that increased upwelling increases juvenile survival
by providing warmer water temperature and greater
habitatavailabi-l-i"cy~-"-c---~"-'--"~
(iii)Effects of Natural Ice Processes on Incubation of
Salmon Embryos (***)
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851021
Mortal.itY'of salmon emhryos in sloughs and side
channels of the Susitna River during the winter has
been estimated in both field and laboratory
.c_QJl.ciif:.:i_Qll~(~J:>_F8rGJ9J~l.t~.,_!~§~.~,_.W.al1ga<!il}:::d all<!.~urg~t'..
1983).Survival of chum salmon embryos from egg
deposition tooutmigrationis estimated to be 12-fS--
percent (ADF&G 1984c, 1985a,1985c).This estimate
is based upon the estimated survival of the entire
population including those eggs deposited in
tributaries.By contrast,sockeye survival is
estimated to be approximately 40 percent (ADF&G
1984c,1985c)•.Since sockeye salmon in the middle
rea.ch spawn almost exclusively in side sloughs and
'-sIae'channelS,-itmayb'eiTJife'rrea that surviva.l of
chum salmon embryos in these habitats is considerably
higher (30 to 40 percent)than the survival of the
chum embryos in tributary habitats (ADF&G 1984c).
E-3-2-100
1
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851021
Mortality rates of Susitna River chum and sockeye
were estimated as part of a laboratory study·of the
effects of temperature on embryo developmental rates
(Wangaard and Burger 1983).Chum and sockeye embryos
were incubated in the laboratory under four different
temperature regimes ranging from averages of 2°C to
4°C,similar to the regimes encountered in the
field.Because of the controlled conditions,the
observed mortality rates of 2-5 percent are
attributable either to temperature itself or to some
other biological factor not associated with the
physical environment (i.e.disease,lack of
fertilization,or genetic disorders).It is assumed
that approximately 5 percent mortality of salmon
embryos in the field could be attributable to similar
causes.Because of the nature of environmental
conditions,it is assumed that much of the remaining
mortality of salmon embryos is attrib~table to
physical processes in the habitat.
Two principal physical factors that could account for
a significant portion of the estimated mortality are
associated with mainstem flow influences on the
slough habitats.These in turn are influenced by ice
processes.The two factors are 1)dessication and
freezing .of the embryos due to the reduction of
mairistem flow prior to ice cover formation and 2)
reduced temperature resulting from overtopping of the
upstream end of the slough (ADF&G 1985a).
Dessication of embryos occurs when the areas in which
the eggs were deposited (redd sites)become dewa-
teredo Spawning occurs during a period (August and
September)when mainstem flow averages approximately
15,000 cfs (ADF&G 1984r).Subsequent to the spawning
period,mainstem flow decreases to approximately
8,000 cfs in October and 2,000 cfs in December and
January.With this decrease in mainstem flow,the
wetted surface area in the individual sloughs and
side channels decreases (ADF&G 1983k, 1983n,
1984r;EWT&A 1984).This is due to reduced flow in
the side sloughs (ADF&G 1983m,1984r,R&M 1985b)and
reduced areas of backwater influence at the mouths of
the sloughs and side channels (ADF&G 1983a).It is
likely that,as the water surface recedes,redds
located along the margins of the sloughs become
dewatered causing dessication or freezing of the
embryos.
E-3-2-l01
851021
As the ice front progresses upstream these areas
could become watered again due to staging and
increased groundwater upwelling.For sloughs and
side channels in the downstream portions of the
reach,the ice formation process could be early
enough in the winter (mid-November to early December)
to prevent dessication or freezing of the embryos.
However,in the upper portions of the reach,ice
front progression reaches the sloughs and side
channels much later (December-January).Hence,it is
likely that mortality of embryos due to dessication
increases from the lower end of the Middle River to
Devi 1 's Canyon.
As the ice front progresses upstream,staging of the
mainstem is sometimes sufficient to overtop the
upstream ends of sloughs.A result is that O°C
mainstem wBter is diverted through the sloughs and
may overwhelm groundwater sources by downwelling of
the O°C surface water.Depending upon the
developmental stage of the embryos at the time of the
overtopping event,the O°Cwater may cause death of
the embryos or may cause developmental abnormali-
ties (Wangaard and Burger 1983).
Laboratory studies of salmon developmental rates vs.
temperature indicate that sockeye embryos are
especially sensitive to thermal (cold)stress early
.__.0 __~in.-the.de.v:elopmentaL process..(Jlelson 1980.,-Bams 1967,
combs 1965).The potential for increased mortality
and developmental abnormality rates due to over
topping was corroborated in the middle river by
observation of large numbers of dead chum embryos,
reduced fry size and higher frequency of
abnormalities in Slough 8A (site 126.0R)following an
overtopping event in 1982 (ADF&G 1983e).Embryos in
other sloughs that were not overtopped did noteihIbitEfle··1.argenUrilber or dea·dembi·-yos or abnormal
In contrast to the three factors discussed above,a
fourth factor,the effects of staging on groundwater
upwelling rates,contributes to the survival of sal-
mon embryos.Upwelling groundwater benefits embryo
development-by providing higher temperatures
(2°C-4.3°C),more constant dissolved oxygen concen-
trations;··andremoval'of -fine'sediments .that may have
a detrimental effect on embryo survival.Upwelling
rates are at least partially dependent upon mainstem
water surface elevation (Exhibit E,Chapter 2
E-3-2-102
. 1
(I
j
)
Sections 2.4.4 and 4.1.2(f)ii),and staging caused by
the ice formation processes.Groundwater upwelling
rates increase with greater mainstem stage and may
contribute to the survival of the embryos.
In summary,several factors associated with winter
flow and ice processes in the mainstem of the Susitna
River affect the survival of salmon embryos during
the incubation period.Factors that tend to decrease
survival are:
o Reduced mainstem flow resulting in dessication
or freezing of the salmon embryos;and
o Overtopping of the upstream ends of sloughs and
side channels diverting the O°C water in to the
sloughs and side channels causing thermal
(cold)stress to the embryos.
A factor which tends to increase survival of embryos
is increased groundwater upwelling.
2.2.4 -Streams of Access Road Corridor (**)
(a)Stream Crossings (**)
The access road to the Watana and Devil Canyon damsites will
depart from the Denali Highway and proceed south to Watana
(see Plate F-32,Exhibit F).From there,the road will tra-
verse the north side of the Susitna River to the Devil
Canyon damsite.A railroad spur from Gold Creek will con-
nect to Devil Canyon.The access road corridor,including
that portion of the Denali Highway to be upgraded as part of
the project,contains at least 45 streams and rivers in both
the Nenana and Susitna River drainages (Tables
E.3.2.21 and E.3.2.56).
The portion of the Denali Highway between Cantwell and the
Watana Access Road crosses 10 streams in the Jack River and
Nenana River drainages (Table E.3.2.56).Fish species
present in Jack River or Nenana River include grayling,
northern pike,burbot,whitefish and sculpin.Of these,the
tributary streams probably contain at least grayling and
sculpin.
From the Denali Highway to Watana,the road will cross Lily
Creek,Seattle Creek,Brushkana Creek,and Deadman Creek as
well as numerous unnamed streams.These streams are tribu-
taries of the Nenana River or Susitna River,and contain
Dolly Varden,grayling and sculpin (Table E.3.2.21).
851021 E-3-2-103
851021
Between the Watana and Devil Canyon damsites,the access
road will cross Tsusena and Devil Creeks (Table E.3~2.21).
The streams contain Dolly Varden and slimy sculpin.
The road will cross the Susitna River approximately 2 miles
(3 km)below the Devil Canyon damsite.Salmon and probably
grayling,whitefish,cottids and longnose sucker occur in
the vicinity of the crossing.The habitat in this reach of
the Susitna is considered relatively poor when compared to
reaches farther downstream.
The railroad between Devil Canyon and Gold Creek will cross
Gold Creek,three tributaries of Jack Long Creek and a trib-
utary of Slough 21 that contains chinook and sculpins (Table
E.3.2.21).The lower reaches of Jack Long Creek contain
small numbers of pink,coho,chinook,and chum salmon.Gold
Creek has been documented to contain chinook,coho,and pink
salmon.
(b)Streams Adjacent to Access Corridors (**)
In additiotl to crossing streams,the Watana access road will
parallel some streams,particularly Deadman Creek.The
fisheries resources are described in Section 2.3.1(a)above.
Devil Creek will also be paralleled by the access road while
the railroad between Devil Canyon and Gold Creek will paral-
lel a portion of Jack Long Creek.
Transmission lines will be built from Watana and Devil Canyon to
Gold Creek and from there to Anchorage and Fairbanks.From Wa-
tana to Gold Creek,the transmis.sion line route is within 1 mile
(1.6 km)of the Devil Canyon access road except near the Watana
Dam.At Gold Creek the transmission lines will use the same
right-of-way as the Anchorage-Fairbanks Intertie,which extends
..from-Will ow.·to Healy........_-
Resources of the Intertie are described in Commonwealth et ale
(1982).At least 27 major salmon streams,including Willow
Creek,Kashwitna River,.Talkeetna River,Chulitna River,and
Indian-River will be crossed by the Intertie and,presumably,by
the additional lines to be built in the right-of-way in conjunc-
tion with the Susitna Hydroelectric Project.The streams contain
grayling,rainbow trout,Do11y Varde.n,and .sculpins .in addition
to salmon.
South of Wi 11 ow,the transmi s sion line wi 11 be routed between the
Susitna River and the Parks Highway for much of its length.It
will cross Fish Creek and the Little Susitna River as well as
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many unnamed streams (Table E.3.2.57).The Little Susitna River
contains coho,pink,chinook,chum,and sockeye salmon;as well
as rainbow trout,Dolly Varden,and grayling.Fish Creek is
known to support chinook,sockeye,pink and coho salmon,and
rainbow trout.The unnamed tributaries to the Susitna River may
also provide salmon habitat.
An underwater cable will be used to cross the Knik Arm.The
transmission line will then proceed east and south to the Univer-
sity power substation.Knik Arm serves as a migration corridor
for five species of Pacific salmon as well as other anadromous
species such as Dolly Varden,Bering cisco,eulachon,and lamp-
rey.The transmission line will skirt Otter Lake,which is
stocked with rainbow trout,and will cross Fossil and Ship
Creeks.Fossil Creek is not considered a fish stream.Ship
Creek supports populations of pink,chum,coho,sockeye,and
chinook salmon as well as Dolly Varden and rainbow trout,but
because of the heavy development along its reaches,it is not
considered prime fish habitat.
North of Healy,the transmisson line will cross at least 50
creeks and rivers including the Nenana and Tanana Rivers
(Table E.3.2.58).These are two of Alaska's major rivers and
provide habitat for salmon,grayling,whitefish,suckers,burbot,
sculpins,northern pike,and inconnu.Panguinge Creek
has been documented to contain coho salmon,Dolly Varden and"
grayling (Tarbox et al.1978).The streams in the Lit tIe
Goldstream vicinity are not considered to be important fisheries
habitat because of their steep gradients.While many of the
streams go dry in the summer,some do support grayling
populations near their mouths.
2.3 -Anticipated Impacts To Aquatic Habitat (**)
Construction and operation of the proposed Susitna Hydroelectric
Project would result in both beneficial and detrimental impacts on the
aquatic habitat and associated fishery resources in 'the Susitna
basin.Many of the potential adverse impacts can be avoided or
minimized through design and/or operation of the project,as described
in Exhibit E,Chapter 2,Sections 3 and 6,and Exhibit E,Chapter 3,
Section 2.4.This section examines the anticipated effects of the
project as proposed in Exhibit A and addresses the impacts likely to be
sustained as a result of project construction,reservoir filling,and
operation of Watana and Devil Canyon dams.Since the project will be
constructed in three stages,impacts to the aquatic habitat are
presented by project stage,and river segment.The discussions focus
on the principal evaluation species/habitat combinations.Discussion
of the impacts to other evaluation species is also presented.
851021 E-3-2-lOS
In this section,the term"impact"refers to a change affected on a
fish population or on its capability to utilize aquatic habitats
resulting from project-induced changes in the physical characteristics
of the environment.Impacts refer to changes or effects that are both
beneficial and detrimental to fish populations.The project may alter
physical characteristics of the aqugtic environment that do not affect
fishery resources,and therefore,these changes are not considered to
be impacts to the resources.The basic project-induced changes to the
physical environment considered in this evaluation includes changes to
the flow regime,temperature/iceregime,and suspended sediment.The
effects of changes in other habitat factors,such as sediment
aggradation,degradation,dissolved gas concentrations,heavy metals,
nutrients,etc.are also discussed for each stage of project
development.
The description of impacts presented below is based on all available
data and analyses through spring 1985.The types of impacts that have
occurred'at>similar projects have also been considered when describing
the probable impacts this project will have on the fishery resources.
The discussion presents to the extent possible,quantitative estimates
of the physical processes,habitat relationships,and likely response
of fishery-resources.
The majority of the anticipated impacts resulting from the construction
and operation of the two dam development will occur during the first
stage of the development of the Watana Dam.Additional impacts,but of
a significantly lesser magnitude,would be sustained as a result of the
addition of the Devil.Canyon Dam in Stage II of the development and the
·rai-st'ng~of~Wgtana~Dam··in~Sfage~III·.·~The~Stage····I~Wat·ana~Dam-wi~H;·alter-·.
the character of the aquatic environment downstream from RM 224,the
uppermost extent of the Stage I reservoir.The magnitude of change in
aquatic habitats below the damsites decreases as the distance from the
damsites increases.A1t;eration of the charactlar ofe.2!:isting aquatic
environment would be most notable within the impoundment zones and the
53-mile (88.3 km)reach between the Devil Canyon damsite (RM 152)and
Talkeetna (RM99).Lesser changes are anticipated in the 99-mile
_(165~km)_r.egch_fromTg..I1,{eettta to Cook Inlet(RMO).Mos tof the
_p-otential imp-acts ~.2..~q ua-ti-ch';bit~-tth~t·ari~~--frOOt da-;-cori~·tr~ctIon
wi'li be avoided through careful design and~siting,and by 'eIilploying--~--"-.~_.,-------.-
best construction management practices.
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2.3.1 -Anticipated Impacts to Aquatic Habitat Associated with
Stage I Watana Dam (***)
(a)Construction of Stage I Watana Dam and Related
Facilities (***)
Potential impacts to aquatic habitat associated with the
construction of Stage I Watana Dam ~nd related facilities
can be divided into three categories:
o Effects of permanent or temporary alterations to water
bodies (i.e.,dewatering,alteration of flow regime,
or alteration of channels);
o Effects on wa·ter quality (i.e.,changes in tempera-
ture,turbidity,nutrients,and other water chemistry
parameters);and
o Effects,both direct and indirect,on fish
populations.
(i)Stage I Watana Dam (***)
The period of construction considered for the
proposed Stage I Watana Dam consists of those
activities occurring from initial site preparation to
the start of reservoir filling.The proposed dam will
consist of a fill structure constructed between
RM 184 and RM 185 of the Susitna River.The fill
will be approximately 0.5 mile (520 m)wide,0.6
(950 m)mile long and 700 feet (267 m)high.Over
32.1 million cubic yards (24.5xl0 6m3 )of material
will be used to construct the dam.
Prior to construction of the Stage I structure,
access will be completed;the diversion tunnels and
cofferdams will be completed and the river diverted
through the tunnels;and site-clearing activities
begun.Heavy equipment will be brought to the site,
and construction material will be stockpiled in the
project area.
Two cofferdams will surround the area of the main dam
construction (see Plate F 5 in Exhibit F).The
upstream cofferdam will be approximately 800 feet
(242 m)long and 450 feet (136 m)wide;the
downstream cofferdam will be 400 feet (121 m)long
and 200 feet (60 m)wide.Water blocked by the
upstream cofferdam will be diverted into two 36-foot
(ll.O-m)diameter concrete-lined tunnels .
851021 E-3-2-l07
851021'
approximately 3300 and 4000 feet long.The
cofferdams and cutoff walls will be constructed
during a two-year period and will remain in use until
reservoir filling begins.
construction of the main dam will have a number of
effects on the river and its biota.Some effects
will be the direct result of construction activities,
while other effects will result from alteration of
the river environment during construction.Impacts
will vary in duration and overall extent,some being
temporary or localized while others will be permanent
or more widespread.
-Alteration of Water Bodies (***)
The greatest alteration of aquatic habitat during
construction of S~age I Watana Dam will occur at
the damsite and at the mouth of Tsusena Creek
where Borrow Area E is located.At the
construction site,the Susitna River flows through
a confined valley with a surface wi-dth of
approximately 400 feet (121 m).The river bottom
is sand,gravel and boulders.The tributaries
closest to the damsite are Deadman Creek at RM 187
and Tsusena Creek at RM 182.Burbot,sculpins,
round and humpback whitefish,and longnose sucker
occupy the dams.ite all year and grayling probably
--~--~-overwinter there--(ADF&G-~1983b}-.·,
The first major phase of dam construction involves
placement of the two cofferdams,thereby permanent-
ly dewatering 0.75 mile (1.3 km)of riverbed at the
damsite.It is anticipated that fish normally
using this stretch will move into adjacent habitats
and that the effects on population size will be
minimal.The ..Q,e.wat:e:J;'e<la:J;'ea:w:i,lJ .e.Y~Jlt:\1ally1:1e.
covered by the Stage I Watana dam;thus,the effect
will bea -permanent but relatively minor-loss of
aquatic habitat and a permanent blockage of fish
movements through this reach.
Gravel mining will be an important activity
associated with construction of the dam and related
facilitiesl.A-nrt-ge--por-t-i(YiC6f the material for
the Stage I dam will be excavated from Borrow Site
-E-at'the-confluence of l'Sl.lSeIlaCreek between RM 180
and RM 182.In the construction zone,Tsusena
Creek is considered more sensitive habitat than the
mainstem of the Susitna River.Anticipated impacts
E-3-2-108
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851021
from gravel removal operations include increased
turbidity caused by erosion and minor instream
activities,introduction of small amounts of
hydrocarbons from equipment operating in stream~
and the possibility of accidental hydrocarbon
spills.These impacts will be temporary and are
not expected to last beyond site operation.A
long-term impact to aquatic habitat is expected at
the mouth of Tsusena Creek.The volume of material
to be removed will result in a pit that will become
filled with water.This pit will create lentic
habitat in exchange for lost ri.parian and upland
habitat.Guidelines and techniques detailed in the
BMP annual entitled "Erosion and Sedimentation
Control"(APA 1985a)will be incorporated into
contractual documents prior to construction in
order to minimize impacts to aquatic habitat from
borrow activities.
Completion of the diversion facH ities in the n;
spring of 1994 will allow the closure of the
upstream cofferdam.Flow will be diverted through
both diversion tunnels during the summer,although
the lower tunnel will pass the greater pOItion.
The upper tunnel begins to pass flow at 8000 cfs.
Tunnel velocities for the average summer flow
(approximately 23,000'cfs)will range between 20
and 30 ft/sec.During the mean annual flood
(43,500 cfs),the river stage upstream of the
project will be raised for a distance of about 2
miles.Immediately upstream of the project this
increase will be approximately 20 feet.Some
ponding will also occur during the average summer
flow.
During the winter,flow will be diverted through
the lower diversion tunnel,which has sufficient
capacity to pass normal winter flows without
significant change to the river stage upstream of
the project.Water velocities in the tunnel will
range from 15 to 20 ft/sec.River ice conditions
are expected to be unchanged from natural
conditions upstream and downstream of the project.
Experiments with fish transport indicate that fish
are adversely affected when water velocities exceed
9 ft/sec (Taft et ale 1975).Relatively few
resident fish occupy the mainstem area immediately
upstream of the tunnels during summer;however,
grayling and other resident species utilize the
E-3-2-109
iIla.iristem to overwinter.Fish that become entrained
in the tunnel flow may be injured or kill~d by the
high velocities,by rocks or other material
transported by the river through the tunnels,or by
impacting the tunnel walls.
High discharge velocities at the downstream end of
the tunnels will scour gravels,sands and silts
from the immediate area of the tunnel outlet.The
velocities will also deter fish from using the area
immediately downstream from the tunnel (Bates and
Vanderwalker 1964;Stone and Webster 1976b),and
will act as a barrier to upstream fish passage (see
Section 2.4.3).
-Changes in Water Quality (***)
The primary change in water quality that is
expected as a result of Stage I Watana Dam
construction is increased turbidity-predominately
caused by increased concentrations of very fine
-sized suspended-particulates.Increases in
turbidity will vary with the type and duration of
construction activity and may be~of significant
local consequence,but are not expected to produce
a widesp~ead detrimental effect upon aquatic
habitat in the Susitna River system.Some of the
first construction activities to take place will
~include--G-1ea-:t'-ing~-a-r-eas,--c-ons"t-r-uc-t-ion-----of-'--access
roads,stockpiling of construction materials and
fuel,movement of heavy equipment,and construction
of support facilities.The construction of support
facilities and the access roads are discussed
below.
Removal of cover vegetation may result in a number
of effects.The removal of cover can increase the.-,.-----.....--".---,--,,------"·-··"-I~ocal------~·run:o-f-f-··:-·-·--c-a'u-sin'g--··-er'o-s-i--o-n-~------------increa-s-ed-----~-.-----~.----_.--~-,-..
.-.-~._--.._-~--_.-.--._.---·------··----------------turoial ty-,and-inc reas'ed di s'sol ved so 1 id s --{LikEi"ns ---
et ale 1970;Bormann et ale 1970;Pierce et ale
1970).The removal of bank cover may also increase
the exposure of fish to predators,and lead to a
decrease in fish populations (Joyce et ale 1980b).
Temperatures in local areas may also increase.
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851021
The movement of nUlriateda1s and the actual pro-
cEf~fs-~of coris!:-ructioii"6rthe-fiII dam -·wi 1I co ril:i1 .....
bute to turbidity and siltation.During the trans-
port,storage,and placement of the fill material
used in constructing the dam,a small percentage
E-3-2-110
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851021
will be introduced to adjacent water bodies,
including the mainstem Susitna River through spills
and erosion.Although the impact on the mainstem
may not be severe,the impact on local clear-water
streams could be significant.
Operation of heavy equipment in streams also in-
creases siltation and turbidity.The extent of the
impact of siltation and turbidity is dependent upon
the extent of machinery operation in the stream
beds and the substrate of the streams affected.
Finer substrates tend to be most affected (Burns
1970),but effects are also dependent upon stream-
flows in the local area.If velocities are suffi-
ciently high,deposition of suspended silts stirred
up by the machinery will not occur locally and the
effects would be minor (Shaw and Maga'1943).Since
velocities can be expected to vary seasonally,the
potential for impacts will vary seasonally as well.
Impacts caused by machinery-induced siltation and
turbidity are expected to be temporary in nature.
Increased turbidity generally reduces visibility
and decreases the ability of sight-feeding fish to
obtain food (Hynes 1966).Most fish species will
avoid highly tu~bid areas and many salmonids avoid
spawning in turbid waters.Temporary increases in
turbidity from activities such as clearing and
gravel removal may occur.
Siltation (sedimentation)is also associated with
these activities.There is a considerable amount
of literature dealing with siltation effects on
fish (Iwamoto et al.1978),particularly the effect
on spawning and incubation.A general conclusion
reached by a review of the literature (Dehoney and
Mancini 1982)is that the greatest adverse impact
of siltation is on immobile eggs and relatively
immobile larval fish.In general,siltation can
cause significant losses of incubating eggs and fry
in redds,particularly by interfering with oxygen
exchange.Areas of upwelling ground water are
affected to a lesser extent than other areas
because silt is prevented from settling.Only
resident fish in the vicinity of Watana Dam,
including Dolly Varden and Arctic grayling,may be
affected by siltation.Entrainment of suspended
materials may also affect other water quality
parameters,such as trace metals and pH,but this
ts not expected to have a significant effect upon
E-3-2-1l1
851021
aquatic habitat in theSusitna system.The
measures planned to minimize impacts of
construction on suspended sediment and turbidity
are discussed in Exhibit E Chapter 2 Sections
4.1.l(c)iii.
The production of concrete for tunnel lining,spill
way and powerhouse construction,and grouting will
generate concrete batching wastewater.Peters
(1979)points out that the discharge of this
wastewater,if untreated,can lead to detrimental
effects on fish populations and habitat.A
particular problem with concrete wastewater is the
need to adjust its pH (10+)prior to discharge.
The measures planned to minimize contamination by
waste concrete are discussed in Exhibit E Chapter 2
Section 4.1.l(c)vi.
Waterbodies can be contaminated during construction
activities by petroleum products that enter from a
variety of sources.Fuels can enter streams,lakes
and wetlands from leaks in storage tanks and-pipes
and from vehicle accidents during transportation.
Poor maintenance of vehicles can also allow small
quantities of petroleum products to enter water
bodies.
Diesel fuel will be used and will have to be stored
onsitein lar-ge quantities-.-Newand--used.
lubricating oils will also be in use.There is a
great deal of literature (USEPA 1976b;AFS 1979)
describing deleterious effects caused by oil
spills.Aromatics in diesel fuel and gasoline are
particularly toxic until evaporated.Heavier oi Is
can coat streambeds and aquatic vegetation and
interfere with production of food organisms
consumed by fish (Kolpak et al.1973).In a river
'as-Targe-a-sthe-siisnna-~-sma:lrspnTsareexpected
to arlute quiCkl:y and not causemeasural51eimpacts;
Spills into smaller tributaries,especially while
incubating embryos are present,could have a
significant impact on resident populations.In the
winter,it is difficult to recover petroleum
spills that flow under ice in rivers.Substantial
morta-li-tycould-resultiftoxic substances reach
overWiriferirigfishcirid'oth.Eir organisms.The BMP
--'--'--'--"-manual ent'ttted""0i!-'spillCdntingencyPlanning"
(APA 1985b)identifies the major elements of an oil
spill contingency plan and also details techniques
for minimizing impacts.
E-3-2-112
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Waste oils containing trace metals require handling
as a hazardous waste under 40 CFR 261-265.Sol-
vents,while probably present in much smaller
quantities than petroleum products,are usually
considerably more toxic to aquatic life.Other
chemicals of concern would include antifreeze,
hydraulic oil,grease,and paints.Factors that
will affect the severity of impacts of a spill
are:
o The substance spilled;
o The quantity spilled;
o Frequency of spills in that area;
o The biota present;
o The life stages present;
o The season;and
o Mitigation and cleanup plans and
preparedness.
-Other Effects on Fish Populations (*)
Other effects that instream construction activities
may have on fish populations include avoidance of
the area,injury,and mortality caused by
instream use of heavy equipment.Heavy equipment
crossings can also damage incubating eggs and
preemergent fry if the crossing location passes
through a spawning area.
Water will be needed for production of concrete,
processing of gravel,and dust control during con-
struction.Impac.ts can result from entrainment and
impingement of juvenile fish as water is withdrawn
from local water bodies.The use of low volume
pumps equipped with proper intake screens will
minimize the number of fish affected.Removal of
water from local water bodies is not expected to
have a significant effect on fish habitat.
Current construction plans do not require instream
blasting.Blasting is planned for areas 500 feet
(150m)or more from streams.A review of the
effects of blasting on aquatic life (Joyce et a1.
1980a,Appendix G)indicates that effects from such
blasting would probably not be lethal (at least
with charges of less than 200 kg of TNT).The
transmitted shock waves from the blasting may dis-
turb fish and perhaps temporarily displace them
from areas near blasting activity.This type of
behavior is well-documented for a variety of noise
E-3-2-113
851021
sources (Vanderwalker 1967 and Latvaitis et ale
1977).Secondary effects of blasting include
increased turbidity and siltation caused by
loosened soils and dust (see effects described
above).The extent of such effects would be
dependent upon the location and amount of
blasting.
(ii)Construction and Operation of Stage I Watana Camp,
Village and Airstrips (*)
During peak construction activity for the Stage I
Watana Dam,facilities to house approximately 3,300
people are anticipated (see Exhibit A,Section 1.13).
The facilities must be located adjacent to the
construction site to simplify transportation to and
from the camps.One campsite is proposed:the
construction camp and village will be located near
Deadman Creek about 3 miles from the dam.This
development will occupy approximately 250 acres
(lot ha).The construction camp and vi llage are to
..be two communities withe separate roads and
facilities.The two communities wi 11 be separated by
natural features,lakes,and fences.After the dam
is completed,a permanent townsite will be developed
either at the construction camp or village site or at
a site to be determined later.
The constrl,l~ti91L~~mR.will.cO.l.!l:~ill t'h~J:Il~lll3._g.~.!Jl~nt
offices,hospital,recreation hall,warehouses,com-
munications center,bachelor dormitories,and other
facilities.It is anticipated that the camp will be
dismantled at the end of the Stage I Watana dam
construction.The construction village will be made
up of 310 temporary housing units and an additional
240 lots with utilities furnished.These
temporary housing units will be used primarily for
·······workers·wlfoare:accompan:i·ed·by·familie-s .andwillat·so
.··b-ere-move-d··wh·en--constructron-·of-Watana-i-s·comp];.et;e-.----··-····
The permanent town will be built to house the
families of employees who will form the operation and
maintenance team for Watana.The town will contain a
hospital,a school,gas station,fire station,store,
recreation center,and offices,as well as
residences.·Constructionofthe town will not begin
until the mid~1990s,since it will not be needed
··untllWatana is-operational.·
A 2500-foot (758~m)temporary airfield will be built
approximately 1 mile (1.6 km)from the construction
E-3-2-1l4
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851021
camp/village site at approximately elevation 2500
feet (760-m).The temporary airfield will be
expanded and upgraded to a 6500 foot permanent
airfield.
-Alteration of Waterbodies (**)
Alteration of waterbodies resulting from the
construction of camps and related facilities will
be confined to the immediate area of the
development.Few adverse impacts are anticipated.
Gravel or other material required for facilities
construction will be mined from local sources or
Borrow Sites D or F,following the guidelines found
in the BMP manual entitled "Erosion and
Sedimentation Control"(APA 1985a).Project
facilities will be located away from waterbodies to
minimize the potential of increased sediment input.__
Overburden will be stored in areas where it will
not affect watrerbodies.
Operation of the camps and airstrips is not expec-
ted to result in appreciable alteration of water-
bodies.
Water will be withdrawn from Deadman Creek.
approximately 7 miles (10 km)upstream from its
confluence with the Susitna River for domestic use
in the camp and construction village.
Approximately 0.5 cfs will be needed to meet peak
demands in both the construction camp and
construction village.This represents less than
orie percent reduction in flow during the open-water
season and less than 7 percent during the winter
season.Little impact is expected to result from
decreases of this magnitude.
-Water Quality Changes (**)
Changes resulting from camp construction areexpec-
ted to be similar to those experienced during dam
construction but impacts would be much reduced in
magnitude because of the relatively great distance
of the camp from waterbodies inhabited by fish.
Turbidity and suspended sediment levels will
increase in areas where erosion enters water bodies
from activities such as installation of the water
intake system,but such effects will be temporary.
E-3-2-115
851021
The most significant impacts on water quality
during camp operations will result from discharge
of treated wastewater into Deadman Creek,oily and
silty runoff from the camps,water used for dust
control,and accidental fuel spills.
Current plans call for pumping water from Deadman
Creek or a series of wells to supply the camps and
town during operations.Treated sewage during dam
construction will be discharged into Deadman Creek.
This sewage system will serve both the construction
camp and village and may be used for the permanent
town after the temporary camp and village are
removed.The solid waste landfill shall be
situated adjacent to the village and camp.Fuel
will be stored within the village and the
construction camp.Details of fuel storage and
handling will be in accordance with contractual
documents that include the information contained in
the BMP Manual entitled "Fuel and Hazardous
Material"(APA 1985d).
The sewage treatment plant will provide secondary
treatment (Chapter 2,Section 4.1.1.g).A lagoon
system will be used to store waste during the year
prior to completion of the treatment plant.The
stored waste will be treated before its release to
the receiving stream.Secondary treatment will
a:v:oidc_many~~of~the~p-r~o_b1 ems ~s§9C tEl t~(LJ~'!~h-_p_l:"~mat'Y
treatment,.such as decreased dissolved oxygen and
increased BOD,increased metals,and bacterial
counts (Warren 1971),although it will introduce
increased levels of phosphorus and nitrogen into
Deadman Creek.Also,if the discharge is treated
with chemicals such as chlorine,residual levels
may have detrimental effects upon aquatic
organisms.Rainbow trout in the Sheep River in.--Canada.-were-reporteatoavoidtfte-a:s-where-
-----clilorinat-e-d--s-ewcrge-e-rfluents-were-di-scharged-,----a-nd--
some fish mortality resulted (Osborne et al.1981).
Grayling,the
primary species in Deadman Creek,are considered to
be sensitive to alterations in water quality
(McLeay et al.1983;1984).The effects of
treated-discharge into Deadman Creek and thence
into the_reservoir will depend upon:(1)the water
chemistry of the creek andreservoir;-(2)the
composition of the treated sewage discharge;and
(3)the dilution of the discharge within the
stream.
E-3-2-116
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Storm drainage and oily water runoff are expected
to occur at both the camp and the village,-but will
be more of a concern at the camp,since this is
where the vehicle maintenance areas,shops,and
related facilities will be located.By providing
proper drainage facilities,ponding areas,and if
necessary,pump stations to pump contaminated water
to the treatment facility,oily and silty water
will not reach Deadman Creek.The small ponds
within the town limits will be more susceptible
than the creeks to intrusions of oily water,storm
drainage,and fuel spills.
Adverse effects may also 'result from oily runoff
from dust control on construction roads and
airstrips and from accidents involving vehicles
transporting fuels.The possible frequency and
severity of such occurrenCeS cannot be predicted at
this time.Runoff from the solid waste landfill is
not expected to adversely impact any aquatic
habitat.
-Other Effects on Fish Populations (***)
Disruption of fish populations during camp and vil-
lage constructiQn is expected to be limited due
to the distance between the camp ,and aquatic
habitats.
Operation of the camps will result in increased
access to an area previously exposed to minimal
fishing pressure.The areas.expected to sustain
the heaviest harvest pressure would be those
stretches of Deadman and Tsusena Creeks and the
Susitna River that are easily accessible from the
camps and the damsite.The resident fish popula-
tions are thought to be at their maximum level,
(ADF&G 1981f,1984a).Studies to date have
indicated a relatively high percentage of "older"
age group fish (up to 9 years).Sportfishing will
inflict heaviest impacts upon larger,older fish
and would likely result in a change in the age
distribution of the population (ADF&G 1984a).
(b)Filling Stage I Watana Reservoir (***)
Filling of the Stage I Watana reservoir will impact aquatic
habitats both upstream and downstream from the dam.During
the filling process,fish populations and habitats will be
851021 E-3-2-117
affected by changes in flow,tempera.ture,and suspended
sediment regimes and changes in other physical and-chemical
habitat factors such as dissolved gas concentrations,
nutrients,and other water chemistry parameters and
constituents.The filling period for Stage I Watana
Reservoir,is expected to be approximately 6 months.
Beginning in May 1998,it is expected that the reservoir
will be filled to between el.1,900 and el.1,970 the first
of October depending upon the Susitna River discharge
upstream of Watana damsite during the summer months.
Discharge from the Stage I Watana Reservoir during the
filling process will be constrained by the Case E-VI flow
requirements defined at Gold Creek (See Exhibit E Chapter 2,
Section 3)from May through October.The Case E-VI flow
constraints ate presented here as Table E.3.2.59.Estimated
average monthly flows at Gold Creek during the'filling of
Watana Reservoir are provided in Table E.3.2.60.The
average monthly flows are presented for Susitna flow
conditions cor'responding to years with a<verage,low (dry
years)and high runoff (wet y.ears).It is anticipated that
the first genera:ting unit will become operational in October
of 1998.Although the project will become operational at
that .time,the available volume in the reservoir for
generation and the available capacity for generation will be
relative~y small.Therefore,during the first winter of
operation,flows in the Susitna River will approximate
natural flows,~.e.they will approach the minimum
operational constra ititsofCaseE-VI-.---
During the summer filling process,dqwnstream releases will
be made through the low level outlet works located in one of
the diversiontun9-els.The low-level discharge structure
has limited capacity to control downstream temperatures.
The effects of filling on river temperatures are discussed
in EXhibit E Chapter 2 Section 4.1.3(c)i.
I
....._~Once thefirsi:generating urlit becomes operational or_~he~__
water level exceeds the minimum operating level for the
outlet works (cone valves),all downstream flows will be
released through the powerhouse and outlet works.Water
will be withdrawn from the upper part of the intake
structure.Therefore~it is anticipated that winter
discharge temperatures and ice processes wi 11 be similar to
na.tura.l co"naitions:.':'..
."impact-sto---the--aqua.-tTc-'reso"tirces are descr:i.he;i"below for the
impoundment zone,the Watana Dam to Talkeetna Reach (middle
river)and the Talkeetna to Cook Inlet Reach (lower river).
851021 E-3-2-118
851021
(i)Watana Reservoir Inundation (***)
Filling the Watana reservoir will inundate
approximately 20,000 acres (8,100 ha).The reservoir
will flood 44 miles (71 km)of Susitna River
mainstem habitat and 15 miles (24 km)of tributary
habitats that would be converted from lotic to lentic
systems with accompanying changes in hydraulic
characteristics,substrate,turbidity,temperature,
and nutrient levels.These habitat alterations will
result in changes to all trophic levels of the
aquatic community presently functioning in the area.
Figure E.3.2.71 shows the area to be inundated by the
Watana reservoir.
Reservoir filling will begin in May 1998 with the
spring runoff flows.During May;the water surface
elevation of the reservoir will rise an average of
7 feet (2.1 m)per day reaching a .depth of
approximately 220 feet (67 m)by the end of the month
(to el.1,670 feet,or 510 m).Increases in water
surface elevation of 5 feet (1.5 m)or more-per day
are predicted in June,3 ft/day (0.9m)in July,and 1
ft/day (0.3m)in August and September.It is
expected that the reservoir will be filled to an
operational level of between el.1,900 and el.1,970
by the end of October,1998,depending upon the
magnitude of the river discharge during this period.
The first generating unit in the Watana Powerhouse is
expected to begin generating in October,1998.
Therefore,filling of the Stage I Watana Reservoir
will be completed in 6 months (See Exhibit C).This
is a significant reduction in the estimated filling
time for the Watana Reservoir configuration presented
in the original License Application (APA 1983b)
-Mainstem Habitats (***)
Impoundment filling will affect mainstem habitats
and fish populations in the impoundment zone.
Since filling of the Stage I Watana Reservoir
will occur in approximately 6 months,discussion of
the anticipated effects to fish population in the
mainstem is more appropriately discussed under
reservoir operations (Section 2.3.l.c.i)
-Tributary Habitats (***)
Impoundment filling will affect fish populations
and habitats in tributaries to the mainstem
E-3-2-119
within the impoundment zone.Since filling of the
Stage I Watana Reservoir will be essentially
complete by the end of October 1998 after beginning
in May 1998,the effects on tributary habitats
during the summer will be similar to those which
will occur during reservoir operation.Therefore,
the effects are discussed,more appropriately and
completely in Section 2.3.1.c.i.
-Lake Habitats (**)
The filling of the Stage I Watana Reservoir will
also effect 11 lakes and ponds in the impoundment
zone.Because of the short duration of the
filling process,the effects of the reservoir
filling on these habitats is more approximately and
completely discussed inc Section 2.3.1 .•c.i.
(ii)Watana Dam to.Talkeetna (*)
-Effects of Altered Flow Regime (*)
The filling of the Watana Reservoir during Stage I
will reduce natural flows at Gold Creek for a
period of approximately 6 months beginning in May.
Estimates of the discharge at Gold Creek during the'
6·month filling period are estimated for three flow
conditions:dry,average and wet conditions.
----------.----.----'rhese-were-selected.·to~representthe-rangeof"
possible discharge conditions which could occur
during the filling process.
The simulation of filling of Watana Stage I is
discussed in Exhibit E'Chapter 2 Section 4.1.2(b).
As stated previously,the rate of discharge release
from the Watana Dam during filling will be
constrained by the Case E-VI flow requirements.
Aithough-'theCase 'E=vI"f'low"consEraTnEsclefine
"mi:iiimumdiscnarge at"\;"oI<rCreeK"on a "wee'Klyoasts",---
average monthly minimum flow constraints were
derived for evaluation of Gold Creek discharge
during the filling process based on the E-VI
constraints.The average monthly minimum discharge
constraints,at Gold Creek;monthly average natural
discharges during the dry,.average and wet
conditions;and estilIlates of the average monthly
discharges dtiringthefilling period in dry,
average and wet discharge conditions are presented
in Table E.3.2.60-.The anticipated effects of
.\
(
851021 E-3-2-120
I
)
851021
these representative discharges on fish habitats
and populations are presented below •
•Effects on Principal Evaluation Species/Habitat
Conditions (***)
Juvenile Chinook Rearing Habitats (***)
Closure of the Stage I Watana Dam and initial
filling of the reservoir will result in the
first major alteration of the flow regime..in the
middle river following start of construction.
The changes to chinook rearing habitat
availability during the Stage I filling period
are estimated by translating the estimated
monthly average discharges to estimates of the
total chinook rearing habitat areas·at those
discharges for all Representative Groups and for
the subset of the habitat areas in Repre-
sentative Groups 2,3 and 4.The translation is
based upon the Habitat Area Response Curves
presented in Table E.3.2.46 and Figures E.3.2.57
and E.3.2.58.
Habitat values for May discharges were not cal-
culated since,under natural conditions,May
constitutes a transition month from winter to
summer.During this period,juvenile chinook
generally move from overwintering areas to
summer rearing areas and outmigrate from the
system.Age 0+juveniles are still in natal
tributary habitats and have not begun to
redistribute into mainstem affected areas (ADF&G
1983m,1984c).
Considering the habitat area in all
representative groups combined,the changes in
discharge attributable to filling of the
reservoir will cause a reduction in the habitat
area available for chinook rearing by,at the
most,15 percent from the habitat available
under natural flows during dry average and wet
discharge years.The habitat areas under
natural and filling discharges and the percent
changes expected in each month are presented in
Table E.3.2.6l for dry,average and wet years •
.This loss of habitat area is expected since the
optimum habitat values are present at discharges
greater than 20,000 cfs (Table E.3.2.46 and
Figure E.3.2.57).For the most part,however,
E-3-2-121
851021
the estimated reduction in the total rearing
habitat is expected to be less than 10 percent.
The reduction in habitat area is not expected to
adversely affect the juvenile chinook population
since the reduction will be of a short duration.
Also,it is emphasized that the habitat area
values presented are only indicative of the
equivalent habitat area which is available
throughout the middle river system and does not
indicate whether or not all of the area will be
used by chinook juveniles.Because of these
factors,the apparent reductions in habitat area
will probably not affect the populations
appreciably.
Considering only the habitat area present at
given flows in Representative Groups 2,3 and 4,
discharge at Gold Creek during much of the
summer of filling will result in an increase in
chinook rearing habitat under any of the flow
conditions analyzed.The total habitat areas
under na.turai and fi lling discharge regimes and
the percent change for each month in dry,
average and wet years are presented in Table
E.3.2.62.The apparent loss of habitat area in
August and September is not considered to be
significant since the maximum reduction is
~n1n~r,v,m~tely'10 percent.
The evaluation of habitat loss and gain
presented here are based on monthly average
flows.As a result,habitat gains and losses
-due to daily and weekly variations of flow are
not accounted for in this evaluation.Under
the natural discharge regime,daily,weekly and
monthly flow variation is expected to be
--------considerabl-y--g·reater--thanduring.._the.actual
.---~-.---._."----~·-f-i-l-l-i.ng--pe.t-i.o.d_.~en.c_e_,du ri ng_"._t he .!_ill~ng .."..
period habitat areas are expected to be more
constant through time than under the natural
discharge regime.
The apparent increases in habitat area in
R.epresentative Groups 2,3 and 4 during the
filling period result from the replacement of
lostsuitableha'bitat art3a pt:t313ent under natural
flows in some sites (Representative Groups 2 and
3)with suitable habitat area in other sites
(Representative Group 4).Thus,loss of habitat
E-3-2-122
I
J
"!
,-j
851021
in some sites is replaced by suitable habitat in
other sites with a net gain in total habitat
area suitable for juvenile chinook rearing.
Adult Chum Salmon Spawning Habitat (**)
During the filling of Stage I Watana
Reservoir,discharges from the dam as
estimated at Gold Creek will affect the ability
of chum salmon adults to gain access to spawning
habitats presently used in side channels and
side sloughs.
Based upon the average monthly discharges at
Gold Creek presented in Table E.3.2.59 and
comparison of the threshold mainstem discharges
presented in-Table E.3.2.49,it is apparent that
there will be some reduction in the suit~bility
of access to specific habitat areas.A summary
of the suitability of the flows for access is
presented in Table E.3.2.63.Based upon the
threshold discharges for the twenty four passage
reaches analyzed,eleven of 24 reaches will be
more difficult for adult chum to pass during
filling those under natural flows in August
whereas only 4 reaches will be more difficult in
September in dry years.In average discharge
year,twelve of 24 reaches will be more
difficult during filling than under natural
flows in August whereas nine will be more
difficult in September.In wet years,twelve
reaches will be more difficult for passage in
August and eleven reaches will be more difficult
in September during filling than under natural
flow conditions.This analysis is based on
average monthly flows and access into the
habitats is attained by chum salmon during a
shorter time period.Short,high-flow events
could occur which would allow access to the
habitat.These high-flow events are not
apparent in the average monthly flows.Also,
this analysis does not account for the influence
of local flow on the suitability of access
conditions (see Section 2.2.3.f.ii).
Although the analysis is conservative,there is
an indication that access conditions for
spawning chum salmon will be adversely impacted
and could require mitigative action.However,
since the effects of filling of Stage I Watana
E-3-2-l23
851021
Reservoir on chum access will occur only during
one summer,the need for mitigative action is
most dependent upon discharge conditions during
operation of Stage I and subsequent development
of the.proJect.
Effects of the discharge regime during the
filling period on chum spawning habitat are
evaluated by translating the estimated monthly
average flows for August and September in dry,
average and wet years presented in Table
E.3.2.60 to total habitat areas in the modeled
chum salmon spawning sites.These translations
are based on the modeled habitat area response
curve presented in Table E.3.2.47 and Figure
E.3.2.59.The average available habitat areas
for dry,average and wet years in August and
September during the filling period and under
the natural flow regime are presented in Table
E.3.2.64.Also presented in the table is the
percent difference between the habitat areas for
natural and filling discharges.
If a low discharge year occurs during the
filling period ,chum salmon spawning habitat
area in habitats currently.used for spawning
(modeled sites)will be reduced in both August
and September by 40 to 60 percent.If normal.
--"(-a ver'age'7~di~schaLge-cis~mai nt'ained duri·ng the-
filling period,the lower discharge in August,
due to filling the reservoir,is expected to
increase the available chum spawning area by
about 20 percent.However,the continuation of.
filling in September and the consequent further
reduction in discharge will result in a loss of
approximately 55 percent of the habitat normally
ava iLab lefor spawning...A.::;:i,mi 1..!l.J:..:i.!1C:!'1?_~J'lE;Jil
.availabl~_E.p-awning habitat area in August and
decrease'in September [s expected {f-dl.scharge"
in the Susitna River is higher than normal.
This pattern of expected gain of habitat area ~n
August and expected loss of habitat area in
September is due to the relatively narrow range
,of flows (11,000-17,000 cfs)corresponding to
optimum habit.g.t areas (more than 79,000 sq ft)
d~p~cf:.ed:il1.FigureE.3.2••59.Under natural
dischargereg:lmes,discharges in the range of
11,000 to 17,000 cfs normally occur during the
first two weeks of September (see Exhibit E,
Chapter 2).Although the anticipated loss of
E-3-2-124
:{
I
I
851021
spawning habitat during the filling period is
significant and probably requires mitigative
action,it must be recognized that the filling
will occur in only one year,short-term,and is
not expected to result in a long-term adverse
effect.
Effects of the discharge regime during the
filling period on chum spawning habitat in
Representative Groups 2,3 and 4 are also
evaluated by translating the monthly average
flows for "August and September presented in
Table E.3.2.60 to total habitat areas in the
groups.These translations are based on the
habitat area response curves presented in Table
E.3.2.48 and Figures E.3.2.60 through E.3.2.63.
Based on these curves spawning habitat available
in Representative Group 2 sites will be reduced
from the habitat available udder the natural
discharge regime as a result of the flows
expected during the filling period in dry,wet
and average years.Chum spawning habitat in
Group 2 sites under natural and filling flows,
and the percent changes,are presented in Table
E.3.2.65.The loss of habitat is expected
because maximum habitat in these sites occurs at
mainstem discharges between 25,000 cfs and
35,000 cfs as indicated in Table E.3.2.48 and
Figure E.3.2.60.
Considerable loss of spawning habitat is also
expected in Representative Group 3 sites except
in August if wet conditions prevail.
Comparisons of habitat areas present in Group 3
sites under natural and filling discharge
regimes during August and September and the
percent changes are presented in Table
E.3.2.66.Habitat values for Group 3 sites
reach a maximum in the range of flows between
15,000 cfs and 25,000 cf~(Table 3.2.48 and
Figure 3.2.61).The slight loss in habitat area
anticipated during August,given wet conditions,
is not considered significant.
As indicated for chinook rearing habitat,chum
spawning habitat in Representative Group 4 sites
is expected to increase in August and to
decrease in September during the filling period
as compared with the habitat available under
E-3-2-125
natural flow conditions.Spawning habitat in
Group 4 sites under natural and filling"
discharge regimes and percent changes are
presented in Table E.3.2.67.The gain in
spawning habitat area in these sites is due
primarily to the peak habitat values for chum
spawning in the range of 8,000 cfs to 25,000 cfs
(Table E.3.2.48 and Figure E.3.2.62).
Summation of the total chum spawning habitat
under natural and filling flows in the three
representative groups and percent changes are
presented in Table E.3.2.68.Replacement
habitat from Representative Group 4 sites for
that lost in Representative Groups 2 and 3 is
likely.The expected overall loss of chum
spawning habitat is less than 5 percent in
August and approximately 15 percent in September
and is not considered significant.This
expected reduction may be overestimated since
chum salmon have been observed to gain access to
and spawn in these areas at discharges similar
to those expected during the filling period in
average and wet years (ADF&G 1983b,1984a)•
•Effects on Other Species/Habitat Conditions (**)
During filling of Stage I Watana Reservoir,
~aisCfiarge~iii tliemiddl"'"E:'f riverwilt~affect other
species/habitat conditions in various ways.It
is not likely that upstream migration of adult
salmon will be affected,by the reduced discharges
in~the river.Access cat tributary mouths for
chinook,coho ,chum and pink adults is not likely
to be adversely effected (Trihey 1983a).Adult
sockeye salmon adult access into spawning areas
..--.~---_._-.-----..-·-~in--side-sloughs{RepresentatiYe_G:c:.()_UP 21~w.Ut ..1:?~
~------~~~---~-~ailected_dudng the filling period ina manner
simi lar to that'described for the effects on----~~~----
adult chum access.
Chinook,coho,chum and pink incubation habitats
in tributaries will not be affected by the
filling flow regime •
.EffectsOJlcohoreat::'kIlg habitats in upland
sloughs are not expected during the filling
period because of the relative independence of
these sites to mainstem discharge.
I
"\
..~
f
.1
851021 E-3-2-126
851021
No effects to outmigration of juvenile salmon are
expected during the filling period since"
sufficient discharge will be available in the
mainstem to allow downstream migration.
Rainbow trout,Dolly Varden and Arctic grayling
generally move into tributary habitats during the
summer months.Therefore,these species are not
expected to be influenced by mainstem discharges
during the filling period until late August and
September.
In September all three species generally move out
of tributary habitats in order to find
overwintering habitats.Some rearing occurs in
tributary mouth habitats and at the mouths of
sloughs.Adult and juvenile rainbow·trout move
into these areas to feed on salmon eggs dislodged
from the spawning areas.Habitats at the mouths
of tributaries and sloughs are expected to be
similar to that observed under natural ..
conditions,but possibly displaced to some
extent.
Burbot are not expected to be affected by the
altered discharge durin~the-fi:lling period.
Burbot are expected to occur in large quiescent
mainstem areas which should be more numerous at
the lower discharge expected during the filliqg
period.
-Effects of Altered Temperature/lee Regime (***)
Estimates of changes to the water temperature at
the out let of the Watana Reservoir during filling
have been made using the DYRESM Reservoir
Temperature model described in Exhibit E,Chapter 2
of this Amendment.(APA 1984g).Estimated outflow
temperature is depicted for the first year of
filling and is presented in Figure E.3.2.72.As
described above,the Stage I Watana Reservoir will
begin filling in May 1998 and will become
operational in October 1998.During the filling
period,water temperatures at Watana Dam will be up
to 7°C cooler than normal during June,whereas,
during July and August outflow temperatures will be
similar to the reservoir inflow temperatures.This
is analogous to the temperatures simulated for the
first year of filling of Watana Reservoir described
in the original License Application (APA 1983b).
E-3-2-127
Although the outflow temperatures may be less than
natural in May and June,the smaller volume
released from the reservoir will facilitate warming
of the water through Devil Canyon Reach.
Therefore,water temperatures within the middle
reach (Devil Canyon to Talkeetna)are expected to
be similar to natural conditions with short lags of
about two weeks,being slightly cooler in May and
June and slightly warmer in September.(See
Exhibit E Chapter 2 Section 4.1.2(e)i).
From October 1998 until May 1999,discharge from
Watana Reservoir is expected to approximate natural
flows.This is due to the combination of low
capacity for discharge frott the dam through the
powerhouse (initially only one generating unit will
be operational,with the additional units becoming
operational in approximately three month
intervals).During the first winter of operation,
temperature of the water discharged from the dam '±'
wiU range from 1...3°C depending upon which intake
port is used to wl.thdraw--water from the reservoir
and the air temperatures and will be cooler than
those shown on Figure E.3.2.72 as discussed in
Exhibit E,Chapter 2 Section 4.1.2(e)i).
During this period,instream water temperature is
expected to decrease rapidly fr01ll 2-4°C at the--Watana Dam-tolfo-cinDeviT C-oinyon.The.rapid
decline in temperature is expected principally
because of the small volume of water to be
discharged.Therefore,ice formation processes Ln
the middle river are expected to be similar to
those described for natural ice processes (Exhibit
E,Chapter 2 and Section 2.3.l.c.ii below).The
major difference between the expected ice processes
....-duringthefirstwinter-of--operationand--naturaL
.-.------·-------------------ice-pt'ocesses-i-s---that--ice-.fo-rmatio_n__in__th_e roi dd 1e
reach will occur several weeks later than it would
under natural conditions.River ice thicknesses
and ice-induced staging are expected to be less
than for natural conditions.
.•_PdncipaJ ..:Eyalua don S pecies/Ha bi ta t
Combinations (***)
During the initial filling of Stage I Watana
effects on juvenile chinook rearing habitats
and chum spawning habitats are not expected to be
impacted by altered water temperatures in the
j
851021 E-3-2-128
851021
river.This is due principally to the
expectation that summer river temperatures will
be similar to natural conditions.
Similarly,no project induced effect on juvenile
chinook overwintering habi~ats in the side
sloughs or chum incubating areas is expected
during the initial winter of project operation.
This is due to the expectation that water
temperatures and ice processes will be similar to
natural.
•Effects on Other Evaluation Species/Habitat
Combinations (***)
Because little change from natural water
temperature is expected during the filling of
Stage lWatana and during the first year of
operation,no effects attributable to altered
temperatures are expected to the other evaluation
species/habitat combinations in the middle
river.
-Effects of Altered Suspended Sediment Regime (**)
Due to ponding of the influent river waters and
turbulence reductions in the impoundment a
substantial proportion of the incoming suspended
sediments will precipitate and become permanently
stored within the new impoundment zone.Downstream
water released for power production,environmental,
or other purposes will be constrained within the
E-Vl flow regime,and will be released through the
low level outlet works located in one of the
diversion tunnels on the river's north bank.Since
waters released during the Stage I filling process
will be drawn from deep in the hypolimnion,near
the floor of the reservoir,the quality of the
released water will be less than optimum for the
downstream biotic community.Although a large
proportion of the la.rger suspended sediment
particles influent to the reservoir will be trapped
behind the dam,downstream releases through the
diversion tunnel will still contain relatively high
suspended sediment concentrations (TSS)and
turbidity (NTU's).Stage I filling releases will
continue from spring 1998 to about October 1998.
Mainstem channels and any peripheral habitats
inundated with these turbid flows will contain less
E-3-2-129
TSS and turbidity than that wbich occurs during the
normal open water season.Direct negative"impacts
to rearing juvenile salmonids in the mainstem or
inundated peripheral habitats are expected to be
minimal as a consequence of suspended sediment and
turbidity changes resulting from Stage I filling
flows.
It is expected that habitats inundated by turbid
release waters during summer will experience
slightly increased euphotic zones compared to what
exists during much of the natural open water
season.The turbid release waters,especially the
particulate portion,will contain high concentra-
tions of nutrients capable of supporting dense·
epilithic communities wbere supplied with adequate
light.Stable substrates immersed in less than 1
to 2 ft.of turbid release waters,with relatively
low velocities (less tha.n 3 feet per second),wi 11
be expected to support epilithic colonization
composed of periphyton (Table E.3.2.69),together
with assorted bacterial,fungal and actinomycetes
organisms.
The luxurient growth and large standing crops of
epilithon which naturally occur over much of the
mainstem streambed in September,October and
November may "be reduced in constantly turbid
-tlabiia t s be c~use··olIi g1iE~nmiEaEi on ....cli.iEfEoh i gh
turbidity.The impacts to the biotic community's
secondary and higher trophic levels because of
changes in the naturally cyclic peri phyton growth
and standing crop of epilithic organisms are
uncertain.
All of the formerly mentioned characteristics of
····the·effectsof·Sl;-age·I-f·il-l-ing··flows.on.mainstem
....._._----_····-·__···_···-·-habi-t-at-s-a·1so-apply--to-side_cha.nne.l.s.,~.ide_§.1Ql!gh.§l.
and other peripheral habitats inundated by turbid
release waters during Stage I filling.However,
since Stage I fi~lingreleases will follow the
minimum flow constraints,and will be more stable
than natural flows,the likelihood of breaching
many peripheral habitats for prolonged durations
will be less than under natural flow conditions.
Th erefcfre ,continuous lywetJ:eQ...PertPl:1er~lha bi ta t s
which are not inundated by turbid release waters
wi111ikely remain as productive or more productive
at the lower trophic levels as they were before
flow regulation.Summertime rearing of juvenile
L
I
I
851021 E-3-2-130
851021
chinook and other salmonids in clear peripheral
habitats is not expected to be negatively impacted,
when compared to the natural situation.
Tributary habitats,for the most part,will not be
affected by changes caused by Stage I filling
flows.Impacts which will occur include reductions
in clear hydraulically mediated,backwater zones at
tributary mouths,and also include increased areas
of the mainstem influenced by clearwater tributary
plumes extending downstream.
Stage I filling releases,since they will contain
substantially reduced TSS concentrations,will
result in less particulate deposition at the mouths
of inundated peripheral habitats compared to
natural deposition processes.The net effects of
reduced TSS concentrations,reduced-replacement of
perviously deposited fine sediments,and
scour/removal of fine sediments by periodic high
project discharges will produce a reduction in
accumulated fine sediments and removal of fine
sediments from many surficial mainstem areas and
peripheral habitat mouth areas.The impacts to the
riverine benthic communities will include:larger
and more stable streambed substrate;larger volumes
of and more heterogenous interstia1 voids among the
streambed substrate;more voids for organic
particulates to accumulate and be processed in;
increased intragravel water circulation in
surficial layers of the streambed substrate;and
potentially better habitat for detrital processing
microbes and some types of benthic invertebrate
organisms.
Minimal and/or reduced primary productivity and
perhaps productivty at all trophic levels is an
expected effect of the altered sediment and
turbidity regime in the reservoir and in
riverine habitats downstream which are chronically
inundated by turbid discharges.
-Effects of Changes in Other Water Quality Habitat
Factors (**)
During the filling of Stage I release waters will
likely contain lower dissolved oxygen
concentrations than are normally found in the
middle river reach,because releases through the
di version tunnel will be .from water near the
reservoir bottom.However,the oxygen deficit of
E-3-2-131
851021
the water near the bottom of the reservoir in Stage
I is not expected to be high due to the sm~ll size
of the reservoir,the volume of freshwater inflow,
mixing effects caused by the low level outlet works
and wind and waves and the weaker stratification
during filling than during normal operation.
Additionally reoxygenation of this water,however,
will occur naturally as it passes downstream
through the turbulent upper reaches of Devils
Canyon rapids.
Stage I reservoir filling discharges will contain
substantial quantities of'organic detritus from the
newly inundated impoundment.Some of this organic
detritus may have substantial food value for
macroinvertebrate communities downstream.However,
such an enhancement in downstream drift of
allochthonous detritus from,the upstream reservoir
will be temporary and rather short-lived,perhaps
decreasing within 1-5 years.
Other water quality changes occurring in the open
water or ice covered seasons due to Stage I Watana
Reservoir filling are not expected to produce
biologically important impacts to fisheries
habitats downstream.It is anticipated that highly
turbid conditions will substantially restrict
reservoir and mainstem river euphotic zones thereby
~~iiiitfimizing-i:m.y-<ietrtment-d--effectsdue-to 'project
induced changes in nutrient concentrations.No
biologically important changes in oxygen
concentration are anticipated for surficial depths
of the reservoir(s)or riverine habitats
downstream.Detrimental biological effects are not
expected to occur in the project reservoir(s)or in
riverine habitatsdownstreaIIl due to project induced
-',changes-.indissotvednitrogenor inj:ota]<:li,,§$Qlyed
_gas..conc_entJ::'_a_tions .._.Basic ionic changes in water
quality which will be caused by the project arenot"
expected to be detrimental to the fisheries habitat
in the reservoir or in downstream riverine habitats
(see discussions of water quality in Exhibit E,
Chapter 2).
(iii)Talkeetna to Cook Inlet (*)
-Effects of Altered FiowReglme (*)
Discharge in the lower river (Talkeetna to Cook
Inlet)during the initial filling will be reduced
by approximately 10,000 cfs to 20,000 cfs during
E-3-2-132
-I
851021
May,June,July and August.The largest reduction
in flow will occur in June with a reduction of
approximately 15,000 cfs to 20,000 cfs.
Natural mean discharges in the lower river,as
measured at the USGS Sunshine gaging station during
the six month filling period are as follows:
May -28,000 cfs,June -63,000 cfs,July -
64,000 cfs,August -56,000 cfs,September -
33,000 cfs,and October -14,000 cfs.
During filling the mean discharge during these
months will be as follows:May -19,000 cfs,
June -44,000 cfs,July -52,000 cfs,August -.
47,000 cfs,September ~26,000 cfs,and October -
13,000 cfs.Similar reductions in discharge at the
USGS Susitna Station will also result from the
filling Stage I Watana.However,the percent
reductions will be 1es~since mainstem discharge at
Susitna Station is greater than at Sunshine Station
(see Exhibit E,Chapter 2,Section 2)•
•Effects on Principal Evaluation Species/Habitat
Combinations (**)
Chinook Salmon Rearing Habitats (**)
As discussed for chinook rearing habitats in the
middle reach,the initial filling of the Stage
I Watana Reservoir will be the first major
effect of the project on fish species in the
lower river.Eighteen sites were evaluated
for chinook rearing habitat availability using
either the IFG-PHABSIM or the RJHAB models
described in Section 2.2.3.d (ADF&G 1985c).
These sites are located in side channel-side
slough complexes or at tributary mouths.
Results of these models are presented in ADF&G
(1985c).The results are reprinted here as
Table E.3.2.70 and Figure E.3.2.73.The effects
of the flow reductions due to filling Stage I
Watana Reservoir can be estimated on a
qualitative basis by comparing the habitat
values for natural and filling flows at each
site.A summary of the expected changes induced
by the filling flows is presented in Table
E.3.2.71.As shown in Table E.3.2.71,various
responses of chinook rearing habitats to the
altered flows in the lower river are expected
E-3-2-133
851021
during the filling process.Some habitats will
improve as a result of filling flows ana other
habitats will deteriorate.Overall,it is
expected that the beneficial and adverse
effects will be approximately equal with no net
loss of juvenile chinook rearing habitat through
the filling period.
Tributary mouth habitats,which are heavily used
by juvenile chinook in the lower river (ADF&G
1985c),will likely be more seriously affected
by the reduced discharges during the filling
period.The principle cause for the adverse
effects will be the loss of backwater effects in
the tributary mouths which provide greater
depth.Apparently,juvenile chinook utilize
deep,clearwater areas with undercut banks or
overhanging vegetation more extensively in the
lower river than in the middle river (ADF&G
1985c).WeIghted Usable Area analyses for
t:rlQ1,lI:8,:rY mouths increases markedly between
mainstem discharges of 45,000 cfs and 60,000
cfs.This effect will be partially compensated
for by tributary flows which will not be
affected by the project.Observations and data
from tributary mouths were collected at times
when both mainstem and tributary discharges were
low.Data were not collected under 'situations
-'of -low .maIlls tem--drscharge and'liigncrioutary
discharge.It is probable that under such
conditions the habitat availability for juvenile
chinook would be greater than is indicated from
the habitat vs.flow relationships depicted in
Figure E.3.2.73 for tributary mouth habitats.
Chum Salmon Spawning Habitats (**)
.......--'A·t"e-l·at-ive·ty-f.ew...chum-.salmon ha:v:.e_b_e_ell observed
to spawn in areas associated with the mainstem
in the lower river.In 1984,a total of 12
sites were identified that were used by chum for
spawning (ADF&G 1985b).The most significant of
these sites is located on the west side of the
_river aJ:_BM~4~.2_ilIunediately upstream of the
mouth of Trapper Creek.Anest::imated total of
3,000 to 5,000 fish were oQs~rved to spawn in
mainstem or side channel habitats in the lower
river in 1984.This is less than 1 percent of
the total number of fish estimated to migrate
past the Sunshine Station.
E-3-2-134
I
I J
.J
i
851021
As discussed above for chum spawning areas in
the middle river,changes to the discharge
regime associated with filling the Stage I
Watana Reservoir are not expected to adversely
affect the spawning habitats utilized by chum
salmon •
•Effects on Other Evaluation Species/Habitat
Combinations (**)
All five species of salmon entering the Susitna
River migrate through the lower river on their
way to spawning areas.since salmon are able to
migrate under a wide range of flow conditions,
changes in discharge resulting from filling of
Stage I Watana Reservoir are not expected to
affect migratory behavior of the salmon.
Rearing habitat for juvenile sockeye,coho and
chum salmon in the lower river will be affecte4
by the changes in discharge as des~ribed for
juvenile chinook rearing habitats.The affects
to the habitats,however,are not expected to
significantly affect the respective populations
of juveniles.The majority of juvenile sockeye
rearing in the ·Susitna Basin occurs in lake
habitats which have outlet streams which flow
into tributaries of the Susitna River.Principle
sockeye rearing habitats are located in the
Chulitna,Talkeetna and Yentna River subbasins
which will not be affected by the project.
Juvenile coho generally utilize small clearwater
tributaries that will not be affected by changes
in mainstem discharge.Rearing of juvenile chum
salmon apparently does not occur in the lower
river to a large extent as evidenced by the lack
of increased size between juvenile collected at
the Talkeetna Station and those collected at the
Susitna Station (ADF&G 1985c).
During the filling periog,rainbow trout,Dolly
Varden,and Arctic grayling will be utilizing
tributary habitats and,therefore,will not be
affected.
Burbot inhabiting the lower river are not
expected to be adversely affected by the changes
in discharge resulting from the filling of Stage
I Watana Reservoir.The expected discharges
during the filling period will be within the
range of discharges occurring in the lower river
E-3-2-135
851021
under natural conditions,and sufficient deep,
quiescent areas will be available for the burbot
populations as described for the middle river.
-Effects of Altered Temperature/Ice Regime (***)
Because little to no change in water temperature is
expected during the filling of Stage I Watana and
the initial winter of operation,no effects on the
evaluation species are anticipated.Migration of
adult salmon to spawning areas,incubation of
salmon embryos ,rearing of juvenile salmon in
mainstem affected areas (side channel complexes and
tributary mouths),.overwintering of juvenile
salmon,and out-migration of juvenile salmon are
expected to remain the same as for natur,al
conditions.Similarly,rearing of rainbow trout,
Dolly Varden and burbot,spawning of adult burbot
and incubation of burbot embryos are expected to
remain the same as for natural conditions.
-Effects of Altered Susp~nded Sediment Regime (***)
Below Talkeetna,water from the middle reach of the
Susitna will mix with other tributary flows.
Little difference from natural conditions will be
demonstratable in lower river suspended sediment
concentrations or turbidity during June,July and
··--Augus t-aurtng-Stag-e-r-Fi-lling;.
LateAugust,.Septemberancl October flows,under
natural conditions,would begin to clear
dramatically.Stage I Filling flows will continue
to be relatively turbid cQmpared to natural flows.
High turbidity is expecte<;l to minimize primary
productivity~in constantly turbid aquatic
No biologically important effects to an
suspended sediment regime are expected to occur in
the lower river,during Stage I Filling,with
respect to fish because.of continuing effects from
other tributaries.
-Effects of Changes in Other Habitat Factors (***)
Other itttportant::wal:erquaIfty changes {tithe lower
river during Stage r Filling are not anticipated
because of dilution effects from other tributaries.
Therefore,no effects on aquatic organisms are
E-3:-2-136
.:/
anticipated which could be attributable to such
changes •.
(iv)Estuary at Cook Inlet (***)
-Effects of Changes in Suspended Sediment
Regime (***)
Demonstrable changes in suspended sediment regime
are not expected at the Susitna River estuary due
to Stage I filling until September and/or October.
Beginning during the fall of 1996,slight to
moderate suspended sediment and turbidity increases
may be expected because of continuously turbid
discharges from the low Watana reservoir.These
increases will be minimal because of substantial
dilution by major upstream tributaries.Effects on
.the estuary are expected to be mostly confined to
mild fertilization due to the nutrients associated
with particulates.
-Effects of Altered Water Quality Due to Stage I
Filling (***)
Because of substantial dilution by the Chulitna,
Talkeetna,Kashwitna,Deshka,Yentna and o.ther "."
tributaries,no biologically important water
quality changes are expected in the Susitna River
estuary during Watana Stage I Filling.
(c)Operation of Stage I Watana Dam (**)
Operation of the Stage I Watana Dam will substantially alter
the existing habitat conditions upstream and downstream
from the dam.The changes attributable to Stage I will
result from operation of the reservoir and from releases
from the dam to meet energy demand requirements throughout
the year.The impacts associated with the operation of
Watana Dam are described below by river reach:impoundment
zone,middle river and lower river.
(i)Effects of Stage I Watana Reservoir Operation (**)
When Stage I Watana Reservoir is filled and becomes
operational,the reservoir will have a surface area
of approximately 20,000 acres (8,100 ha)at its
normal maximum water surface elevation of El.2000
ft.At the normal maximum water surface elevation,
the reservoir will inundate approximately 40 miles of
mainstem habitat,approximately 15 miles of tributary
851021 E-3-2-137
851021
habitat and 11 lakes and ponds ranging in size from
less than one acre to approximately 5 acres.
Seasonal variations in the surface area of the
reservoir will occur as a result of project
operation.The reservoir will be filled to the
normal maximum operating water surface elevation of
2000 ft.MSL by the end of the summer (approximately
by September 1).During the winter months (beginning
approximately October 1),the reservoir will be drawn
down because power release flows will be in excess of
inflow to the reservoir.Drawdown will continue
until approximately May 1,when the summer refill
period will begin..The maximum drawdown of the
reservoir by the end of April will be 150 ft.below
el.2000 or to el.1850 ft.At el.1850 ft.,the
reservoir will have a surface area of approximately
12,000 acres.During the winter months,the average
rate of drawdown of the water surface elevation will
be approximately 0.7 ft.per day.Refilling of the
reservoir will begin at the onset of the open water
period,approximately May!.If refilling is
complete by the end of August,the average rate of
rise in water surface elevation will be approximately
1.3 ft.per day.A schematic of the drawdown-refill
cycle for the Stage IWatana Reservoir is..p:resented
as Figure E.3.2.74.
-Effe.~ts.1:0_Mainstem Hap~tat_(**)
Impoundment of the Susitna River by Watana Dam will
alterthe-physica:lcharacteristics of mainstem
habitats and consequently affect the associated
fishery resources.Burbot,longnose sucker,and
whitefish generally occupy mainstem habitats
year-round.Arctic grayling use mainstem habitats
for overwintering (ADF&G 1981f,1983b).
.....___.___.
.-----.---Mainstem-habita-ts--woul-d--be--e-];-iminated--by-·the----_.------
impoundment and replaced by a reservoir
environment.The expected physical characteristics
of the reservoir are presented in Exhibit E,
Chapter 2,section 4.1.1
Water quali.tyconditions expected in the reservoir
are discussed in Exhibit E,Chapter 2,Section
-4.1.3,c and are not-expected to preclude fish
utilization of the reservoir area.
E-3-2-138
.!
851021
At present,mainstem habitats are utilized by bur-
bot during the open-water season.Longnose sucker
and whitefish generally occupy mainstem habitats
only in the vicinity of tributary mouths (ADF&G
1981f,1983b).Burbot,longnose sucker,and
whitefish are found in glacial lake environments Ln
south-central and southwestern Alaska (Bechtel
Civil and Minerals,Inc.1981;Russell 1980).
Since these fish are associated with habitats
similar to those that will be present in the
reservoir,conditions within the reservoir during
filling are not expected to adversely affect these
species.Thus,these species are expected to
utilize the reservoir habitats year-round after the
reservoir is filled.
Burbot are found throughout interior Alaska and
inhabit both rivers and l~kes.They generally
prefer low light conditions and are often
associated with turbid water environments.The
Watana Reservoir should offer suitable habitat for
burbot.However,burbot spawn in relatively
shallow water (1-5 ft)over sand,gravel and stone
substrates.Eggs settle to the bottom where they
develop (Morrow 1980).Since spawning occurs in
January and February,it is likely that some burbot
will spawn in shallow areas of the reservoir at a
time when the reservoir is being drawn down.As
the reservoir is drawn down further,the eggs may
become dewatered and either dessicate or freeze.
This will result in a reduced recruitment rate to
the population.A few burbot may move into the
upper Susitna or Oshetna River to spawn (Morrow
1980);however,mark-recapture studies indicate
that burbot are rather sedentary (ADF&G 1983b,
Morrow 1980).
A burbot population is expected to remain in the
reservoir area,and could expand over existing
populations.However,the densities are expected
to remain low due to reduced recruitment and
reduced food supplies.Because this species is not
highly sought by fishermen,any reduction in
population density is not considered significant
and,therefore,does not warrant mitigative
action.
Burbot spawning areas may be located in mainstem
habitats near tributary mouths.These areas will
be inundated during the first year of filling,
E-3-2-139
-~-_._-_.._---
851021
eliminating their present value as spawning areas.
Since the habitat in the vicinity of tributary
mouths would be changing rapidly,it is unlikely
that stable spawning areas (similar to those
presently existing)would develop during reservoir
filling.The loss of spawning habitat is expected
to adversely affect burbo~production in the
proposed impoundment.
Water depth,water quality,and food availability
are critical factors associated with overwintering
habitat (Bustard and Narver 1975;Tripp and McCart
1974).The reservoir is expected to provide
adequate depth and water quality conditions for
overwintering fish.Species which currently
overwinter in mainstem habitats are Artic grayling
and Dolly Varden.Suspended sediment'
concentrations in the impoundment are expected to
be tolerable for fish,although considerably higher
than existing suspended sediment concentrations in
the mainstem Susitna River during the winter.
Particles less than 5 to 10 microns in diameter are
expected to remain in suspension (Exhibit E,
Chapter 2,Section 4.l.3(c)(iii».Overwintering
fish in lake habitats with suspended glacial flour
levels similar to those expected for the Watana
Reservoir are reported from other areas (Russell
1980;deBrugn and McCart 1974).When filled,the
res ervo i rwi-ll-inc-rease the amounto-f---habitat
having suitable conditions for overwintering fish.
The incr~ase in overwintering habitat may have a
beneficial impact on fish resources of the upper
s~s:i.tlla,J)asin above the Watana Dam,if lack of
available overwintering habitat presently limits
fish populations in the area.
W.i!lt:~l:"_l:"~tl:lf?~l:'y():i.r !I1.a.I:.~r_t:_~IIlP~r~t:t1!'~~IIlc:lY!.!'!c r eo!:!.l;~.
the quality of overwintering habitat in the upper
Susitna basin.Reservoir temperatures in the top
100 feet (30 m)are expected to be in the range of
ooe to 3°e (33.8 to 35.6°F)(Exhibit E,Chapter 2,
Section 4.1.3.c.i.).Present winter water
temperatures in mainstem habitats in the proposed
impoundment area are near O°C (32°F).These warmer
Water temperattiresmay benefit fish by increasing
overwinter survival •.._During the winters of
1981...1982,1982"'1983arid1983~1984,fish·iIlhabitirig
the middle and lower river apparently sought out
water with warmer temperatures (ADF&G 1983e,
1985a).Other investigators have reported that
E-3-2-140
,]
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851021
fish prefer warmer water areas in the winter (Umeda
et al.1981).
-Effects on Tributary Habitats (**)
Stage I Watana Reservoir will inundate portions of
four named tributaries:Deadman,Watana,Kosina,
and Jay Creeks (Figure E.3.2.7l.)At the maximum
surface elevation of 2000 ft.MSL,the reservoir
will extend into the tributaries various distances,
depending upon the location of the tributary
confluence with the river or reservoir and the
gradients of the tributary streambeds.The
locations,lengths and gradients of tributaries
affected by the Stage I Watana Reservoir are
summarized in Table E.3.~.72.Because of the
annual drawdown-refill cycle,certain portions of
the inundated tributary reaches will alternately
exhibit tributary or reservoir characteristics.
Assuming a maximum reservoir drawdown of 150 ft,
the approximate lengths of tributaries within the
drawdown zone are generally less than 2 miles.
These are presented in Table E.3.2.72.Lengths of
tributary reaches which will be permanently
inundated,i.e.not within the drawdown zone,are
also presented in the Table.
All of the four named tributaries are inhabited by
Arctic grayling populations wh~ch will likely be
adversely impacted by the Reservoir.The initial
filling and annual refilling of the reservoir will
begin in May each year.This coincides with
grayling spawning activities in the lower portions
of the clear water tributaries.Arctic grayling
spawn during spring breakup,with embryo incubation
lasting 11 to 21 days (Morrow 1980).Spawning
areas in the lower portions of the tributaries will
be inundated in May and June during the initial
filling of the reservoir.During reservoir
operation,artie grayling will spawn in the
tributaries upstream of the reservoir surface
elevation in May and June.Since the reservoir is
at its minimum level during this time and will
begin to rise as the summer high flows are stored,
some of the spawning sites will be inundated prior
to their hatching.Hence,only those spawning
areas sufficiently far upstream from the reservoir
that the embryos hatch before the area is inundated
will provide a source of recruitment for the
grayling population.
E-3-2-141
Arctic grayling depend·on tributary habitats for
summer rearing areas.Grayling are not expected to
occupy reservoir habitats during the summer as they
are not found in lake habitats with turbidity
levels similar to those projected to occur in the
reservoir (Russell 1980).(See Exh ibit E,Chapter
2,Section 4 .1.3(c)(iv)for projected impoundment
turbidity levels).Under existing conditions,
grayling population densities in tributaries range
from 323-1835 fish per mile (Table E.3.2.24,ADF&G
1981f,1983b).The total number .of Arctic grayling
estimated to occur wi thin the Stage I impoundment
area is approximately 11 ,000 fish.Grayling
occupying tributary habitats inundated by the
reservoir will likely be lost because of lost
rearing habitat.A small percentage of these
grayling are expected to remain in the reservoir
near tributary mouths.
Approximately 2 miles (3.2 km)of Deadman Creek
will be inundated by the reservoir at full pool.
Presently ,a waterfall located about 1 mile
(1.6 km)upstream from the mouth prevents upstream
fish migration.The reservoir will inundate th is
barrier and allow fish passage to the upper Deadman
Creek and Deadman Lake.Since the available
habitats in Deadman Creek are presently occupied by
grayling,the inundation of this barrier is not
.-__expec.te.d~to_imp.roy.e gray lin gp.rQduct_ion.i.t'LUP per
Deadman Creek.
DollyVardeii will beauly slightly affected by the
inundation.Dolly Varden occupy a wide range of
habitat types iii south-central Alaska including
glacial lakes with a wide range of water quality
(Russell 1980).In the project area,Dolly Varden
occupy tributary habitats during the open-water
---------.-.--.-------se-asori--a:n:d~-cffEer--spawning·;returiftothems-instem
.....c-:__._.__..·_·tcr-bverw-hftEn.~-r-t"""rs-anH-cip·ate·d-·-that-Dol·1y ··Varden---·
will occupy reservoir habitat year-round.
Dolly Varden spawn in the fall,the embryos
incubate through the winter,and the alevins emerge
in the late spring.Al though the reservoir will be
drawn down durin.g the spawning and incubation
peri('jd,arty·;sp~wtfingareas available in the fall
·would:~nothe~affected·'sincethe areas ·will be in
tributaries upstream of the reservoir.
•
-,j
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]
851021 E-3-2-142
851021
-Effects on Lake Habitats (***)
Eleven lakes and ponds will be inundated by the
Stage I Watana Reservoir.The only pond known to
be inhabited by fish is located on the floodplain
along the left side of the Susitna River (looking
downstream)near the mouth of Watana Creek.The
pond is inhabited by a population of Dolly Varden.
However,no information .is available pertaining to
the size of the population.The Dolly Varden
present in this pond will probably respond to
inundation similar to the populations inhabiting
the tributaries.
(ii)Watana Dam to Talkeetna (***)
- E ffec ts 0 f Al tered F low Regime (***).
Operation of the stage I Watana Dam is expected to
begin in October of 1998 with the firat commercial
operation of the first generating unit.The
project will become fully operational with the
commissioning of the fourth generating unit in
the summer of 1999.Once the _pro ject becomes
operational,the discharge regime downstream from
the project will be al teredfrom the filling regime
and the natural discharge regime.In general,
operation of the project will result in lower than
natural discharges in ..the river during the pe:riod
Mayth rough September,and,higher than natural
discharges from October through April.
In addition to changing the general discharge
regime through the year,a further change will be
the reduction of peak flood events.As described
in Exhibit E,Chapter 2,flood event peaks are not
expected to be as high but may be of longer
duration due to the storage capacity and operation
guidelines of the reservoir.
Discharge from the Watana Dam is constrained,on
the one hand,by the Case E-VI flow cons traints
defined for discharge requirements at Gold Creek.
On the other hand,discharge and,thereby,energy
production from Watana Dam are constrained by the
storage capacity of the reservoir.Within these
constraints,discharge from the dam and at Gold
Creek will be dependent upon the energy demand in
the system,the capacity of the units to generate
power,and the amount of water available.Although
E-3-2-143
it is expected that as energy demand grows from
early years of Stage I operation,discharge should
alsdincrease,particula~ly during the winter
months,and,consequently,summer discharges ~hould
decrease commensurate with a larger drawdown of the
reservoir.However,because Stage I Watana
Reservoir has a limited storage capacity,the total
energy production capacity of the Stage I project
is limited.As discussed in Exhibit B,energy
demand in the system during Stage I operation is
expected to grow from approximately 4,520 gigawatt
hours (GWH)to approximately 4,760 GWH from 1999 to
2004.Energy production from the project,however,
will grow from approximately 2,280 GWH to
approximately 2,310 (;wH.Therefore,the flow
regimes for Stage I operation may be represented by
th9se associated with an average demand of .
approximately 4,670 GWH and an average energy
production of approximately 2,300 (;wH.The average
weekly discharges at Gold Creek>for the 34 years of
record are presented in Exhibit E,Chapter 2,
Section 4.1.3.The mean,minimum,and maximum
,average monthly flows at Gold Creek for the
observed 34 years of record for the natural and
Stage I flow regimes are presented in Table
E.3 ..2.73.The average monthly and mean average
monthly discharges were·derived from the average
weekly discharges for natural conditions and Stage
.I~oper.ation •..~Habitatanalyses.described __bel ow wer e
conducted using the weekly average discharges for
the 34 years of record.
To determine the effects of the altered flow regime
on aquatic resources,it is necessary to translate
the weekly average discharge values to
corresponding weekly average habitat area values.
This translation is based on the habitat area,....._~---,--------~--"----_.-_.-----··,-~----"---~--:·r-~i-s:iio-iis~e~--c-u'rv-es---'p"res-eiit-e'f---'-iii-"·S"e-c---Ei-on--"'--2--~~2-'~-J--~--e-'-:-
-----~~--_.---_...--------------··-----prCfbaDil-i-ey of,occurrence curves (per-cert-e-----.---.--.---.-.----
exceedence curves)and time series (sequential)
analyses of the resul ting habitat area val ues were
prepared and compared with the percent exceedence
and time series analyses results presented in
Section 2.2.3.f to determine the expected effects
of the altered flow regime.For the purposes of
thispreseritatiori,only the probabilities of
'oc'currence'(percentexceedence}val ues are
presented with some reference to the time series
analysis.
'J
:..j
'1
II
II .
I I
,'j
,Ie:..'
851021 E-3-2-144
j
I
.)
851021
•Effects on Principal Evaluation
Species/Habitat (**)
Juvenile Chinook Rearing Habitats (**)
As described in Section 2.2.1.a,juvenile
chinook salmon inhabit mainstem affected areas
in the middle river throughout the year.
Throughout the summer,open-water months,the
juveniles in the mainstem affected areas occupy
habitats which are commonly characterized as
having turbid water.Densities of juveniles
in turbid water areas are generally more than
twice those in clear water habitats (ADF&G
1984c).During the ice-covered period,juvenile
chinook are found in the greatest concentration
in areas influenced by groundwater upwel-ling.
Because of these differences in habitat
utilization between summer and winter months,
the analysis of the effects of the altered flows
associated with Stage I operation is separated
into the two periods.Focus for the Qpen water
season will be for the period June through
September and focus for the ice-covered season
will be for the period November through April.
The months of May and October .corkeapond to the
transition from winter to summer conditions and
from summer to winter condi tions in both the
natural and Stage I operation flow regimes.
The probability of occurrence and frequency
analysis of the weekly average habitat areas is
based on the translation of weekly average
discharges in the 34 years of record to weekly
average total habitat areas.Total habitat
area values for each weekly average discharge
are derived from the total habitat area response
curve presented in Table E.3.2.46 and Figure
E.3.2.57.In addition,flows were translated to
habitat areas included in Representative Groups
2,3,and 4.The translations using this subset
of the representative groups were made because
these groups represent the types 0 f habitats
which are currently most heavily utilized by
juvenile chinook (particularly Representative
Groups 2 and 3)and those expected to be most
similar,under project conditions,to those
currently utilized.The habitat response curve
for this subset of Representative Groups is
presented in Table E.3.2.46 and Figure E.3.2.58.
E-3-2-145
851021
Translations of the weekly average flows to
Translations of the weekly average flows to
habitat areas in each of the respective
Representative Groups were not made.Therefore,
the differences in habitat areas between natural
and with-project discharges incorporate the
replacement of habitat areas lost in one group
of sites by habitat areas gained in another
group of sites.Thus,the observed differences
presented below represent the net changes in
chinook rearing habitat areas attributable to
Stage I operation for the open water season.
During Stage I operation,the median total
habitat area for chinook rearing in the 34 year
simulation during the summer months is expected
to be nearly the same as the median total
habitat area available under the natural flow
regime.The median habitat area values (i.e.
the 50 percent exceedance values)for the Stage
I flow·regime and the natural flow regime for
each week are pre sented in Table E.3.2.74.Al so
presented in the table are the 90 percent and_
10 percent exceedance values for the Stage I and
the natural flow regimes.These values are
dipicted graphically on Figure E.3~2.75.
Habitat areas expected to be equalled or
~XC e5!<ied.1Qp~et;'g~1'1I:QI _1:1l~t:Lm~._u.l'1d et;'.the.S t"",ge
I flow regime during the first half of the
summer are somewhat less than the areas equalled
orex~eededlO percent of the time under the
natural flow regime.However,by mid-summer,
i.e.by Calendar Week 30,the range of val ues
for available ch inook rearing habitat area under
the Stage I flows is nearly the some as under
natural flows.Two points must be emphasized
····_··_·_-_···,'_·witn-re·ifpeH::·t--tO·tne'ifpp;ifrelit-reduct iOn-ilithe
----··--ava-i-l-a-b-l·e-·ha'b-i1:at'-·areas-f·or~·the---£i:rs't~·part-of-'~--"'".
the summer.First,as indicated in Figure
E.3.2.37,juvenile chinook generally do not
become prevalent in mainstem affected areas
until the first part of July.Thus,reductions
in available habitat area during the earlier
time period wilL not affect the populations.
Secondly,the resul ts of this analys is indicate
,only-the total equivalent surface area which is
suitable for chinook rearing and does not
necessarily mean that juvenile chinook will use
all of the suitable habitat area available.
E-3-2-l46
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851021
The reduction in the habitat area equalled or
exceeded 10 percent of the-time,evident during
the first weeks of the summer,is due primarily
to the fact that Stage I discharges in the early
summer weeks are not sufficiently great to
achieve the peak habitat area values present in
Representative Groups 2,5 and 8 (See Figure
E.3.2.56).With the exception of Representative
Group 2,groups which provide optimum habitat
area at discharges greater than approximately
25,000 cfs (e.g.Representative Groups 5 and 8)
are not known to be heavily utilized by juvenile
chinook for rearing under natural conditions.
Therefore,the apparent reduction of habitat
area in these groups,reflected in a total
habitat reduction,is not expected to affect the
juvenile chinook populations.
In contrast,by considering only the habitat
areas included in Representative Groups 2,3 and
4 (Figure E.3.2.58),it is evident that habitat
currently used extensively by juvenile chinook
will increase as a result of the Stage I flow
regime.Habitat areas representing the 90,50,
and 10 percent exceedance values for the three
representative groups are presented in Table
E.3.2.75 and depicted in Figure E.3.2.76.the
values for the natural flow regime are presented
for comparison.The major cause for the
expected increase in habitat area is that
considerable habitat is present in sites
included in Representative Group 4 at lower
discharges,in the range of project flows,than
is present at higher discharges in the range of
natural flows.Although the habitat areas that
are used by juvenile chinook under natural
conditions (i.e.in Representative Groups 2 and
3)may be lost due to the lower discharges
associated with Stage I operation,habitat areas
in Representative Group 4 sites will be gained.
Hence,lost habitat areas used by chinook
juveniles under natural flows will be replaced
by suitable habitat areas in other sites.
A further characterization of the estimated
habitat areas under the Stage I flow regime is
that the range of variation in habitat area from
week to week and from year to year is relatively
narrow as shown in the figures.Comparison of
the range of habitat areas for natural
E-3-2-147
851021
conditions,also presented in Figure E.3.2.74,
with those expected during Stage I operation,
indicates that under the project flow regime,
even though the total ch inook rearing habitat
areas will be less than under the natural flow
regime,the habitat areas will be more constant
through time •.This is also true for the
Representative Groups 2,3,and 4.The range of
habitat areas included in all sites and included
in Representative Groups 2,3,and 4 under the
natural flow regime are superimposed on the
respective ranges of habitats under the Stage I
flow regime in Figures E.3.2.75 and E.3.2.76 for
comparison.Based on this analysis,it is
evident that the primary goal of the Case E-VI
flow regime to maintain the chinook rearing
habitat is achieved.In fact,the chinook
rearing habitat expected to be available in the
three representative groups during Stage I
operation wi~l be greater than that available
with the natural flow regime.
During the winter,juvenile chinook generally
move into areas influenced by groundwater upwel-
ling as described in Section 2.2.l.a.i.Because
mainstemdischargeduring the winter months will
be greater during Stage I than under natural
conditions,the availability of clearwater area
in",fu~e areas whisll~~~~~llrr~I!1::lJr_ll~~~~J)yJUYla-
nile chinook is expected to be greater during
Stage I.The increase in area used by chinook
for overwintering is expected even though the
mainstem i~expected to be turbid.Turbid water
from the mainstem will not affect these over-
wintering areas (i.e.the side sloughs).Thus,
the clarity of mainstem water is not relevant.
The increase in clearwa ter area is expected both
·as-a--resul-t--of--the increased mains tem-~discharge-
····--ca·us~ing~~increa·sed~-backwa·t:er~are·as--a-t-t:he--mou-ths---
of clearwat!=!r channels,and as a result of
increased rates of groundwater upwelling (APA
1984g).Since clearwater overwintering habitats
aI'!=!expected to be more extensive during Stage I
project operation,juvenile chinook survival is
.also expected to be greater.
However:;a factor which could offset·this
expected increased survival is the effect of ice
.process~s associated with the Stage I discharge
and temperature regime.Given the Stage I
E-3-2-148
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851021
discharge regime,formation of the ice cover is
expected to begin somewhat later than.un~er
natural conditions.The formation of an ice
cover will cause the water surface elevation to
increase significantly.This process is
discussed in more detail in Exhibit E,Chapter
2,Section 4.l.3.c.ii,by HE (1984a),and by R&M
(1984,1985b).Staging of the water surface
would be sufficient to cause diversion of
mainstem discharge into clearwater habitats used
by juvenile chinook during the winter months.
The diversion of O°C mainstem water into these
habitats would increase the mortality of
juvenile chinook because O°C water will reduce
the ability of the juveniles to maintain their
positions and the increased velocities
associated with the diversion of water into the
channels would tend to displace the juveniles
downstream,out of the sites.In addition,it
is expected that mainstem discharge will remain
turbid through the winter months.Hence,
diversion of turbid water into the overwintering
areas could cause reduced survival of the
juvenile chinook due to increased physiological
stress.However,this is not expected to be
significant.
The ice front is expected to progress only part
of the way up the middle river,with some of the
reach remaining ice free.Chinook juveniles 1n
sites within the ice-free reach are expected to
exhibit higher survival rates than those in
sites within the ice covered reach.In the
absence of mitigation efforts designed to
protect peripheral habitats,overtopping of the
overwintering habitat sites in those areas
influenced by an ice cover could result in a
generally adverse effect on juvenile chinook.
However,in general,survival of overwintering
juvenile chinook is expected to increase under
the with-project flow regime.
Chum Spawning Habitats (**)
As described in Section 2.2.La,chum salmon
spawn during August and September each year.
During Stage I operation,discharge at Gold
Creek will increase over the previous months
(June and July)because the Stage I Watana
Reservoir will be filled.Therefore,most of
E-3-2-149
inflow to the reservoir will be discharged
downstream either through the turbines or
through the outlet works.As indicated in Table
E.3.2.73,mean discharge at Gold Creek will be
approximately 18,000 cfs in Augus t and
approximately 14,000 cfs in September as
compared with mean flows of 22,000 cfs and
13,000 cfs,respectively,under the natural flow
regime.Because the Stage I operational
discharges in August and September will be
similar to those under the natural flow regime,
access to traditional spawning areas used by
chum salmon in the mainstem are not expected to
be adversely affected.A summary comparison of
natural and Stage I operation access conditions
at several chum spawning habitats is presented
in Table E.3.2.76.Based on the mean average
month ly discharge at Gold Creek,c access
conditions through six of the 24 passage reaches
evaluated will be adversely affected by the
Stage I flow regime in August whereas only one
passage r.eachwill.be adversely affected in
September.In general,major adverse effects on
access to chum spawning areas,particularly
through those passage reaches directly affected
by mainstem backwater,are not anticipated.
Analysis of the effects to chum spawning
__'-'~_habi.ta t_s_w.ascp.er~fo_rme.d_using_theha bikat ~re09.
response curve developed for the modeled sites
(Table E.3.2.47 and Figure E.3.2.59).Sites
included in this curve provide spawning habitat
for over 70 percent of the adult chum which
spawn in non-tributary,mains tem-affec ted areas
in the middle river.
Translation,of the simulated weekly average
"-drscha-rgesfo~rthe-34-yearsofrecofotoweekly
.....-------.--.-------.---.---~--~.aver;:q~e~h-a-bt·t;:rt-ar·ea-s--us·tn-g-·-tn-i-s--curve-wa's--p'er"".
fonned and a fr.eq uency analysis conducted.The
analysis was conducted for simulated average
weekly discharges during August and September.
The habitat areas available in the modeled sites
expected to occur at least 90 percent,50 per-
..--cent ·andlOpercent of the time are presented in
Table E.3.2.77 for the expec ted flows during
-'--StageI-operati-on-o'Habitat areas in these sites
under natural flows are also presented for
comparison.These.val ues are depic ted
graphically in Figures E.3.2.77.Comparison of
'j
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851021 E-3-2-l50 )
:l
851021
the median spawning habitat values obtained for
the Stage I operational flow regime with the
values obtained for the natural flow regime,
reveals several conclusions regarding the
effects of the Stage I operating regime under
the Case E-VI flow constraints.Throughout
Stage I operations median habitat values will be
equal to or greater than the median values
present under natural flow conditions.This is
most pronounced for the last part of September
when natural discharge declines prior to the
beginning of winter.Discharge in the last part
of September with Stage I operating will be the
same as the optimum flows for chum spawning
habitat (approximately 14,000 cfs,Table
E.3.2.47).
Spawning habitat areas equalled or exceeded 90
percent of the time will also be greater during
Stage I operation due pri~ipally to the
reduction of high weekly average discharge
events which normally occur as a result of
storms.Discharge of the storm-related high
flow events through the reservoir will occur
over a longer period and will not reach the peak
levels observed in the unregulated river •.
Similarly,naturalliY occurring··low flow events
near the end of September,which are associated
with low habitat area values,will be augmented
by the Stage I operation in response to the
minimum Case E-VI flow constraints and the need
to discharge water for power generation.The
overall effect of the Stage I operational flow
regime,then,is that more habitat area is
expected to be available for chum spawning and
the week to week and year to year variation in
the amount of spawning habitat area available
will be reduced.
A similar analysis of chum spawning habitat was
conducted during the aggregate habitat area
response curve for Representative Groups 2,3
and 4 presented in Table E.3.2.48 and Figure
E.3.2.63.Using this habitat response curve,
somewhat different results are obtained.
Total habitat areas during Stage I operation for
chum spawning during August and September are
expected to decline somewhat from those
available under the natural flow regime.Chum
E-3-2-151
851021
spawning habitat areas in the three
Representative Groups,expected to be-available
fifty percent of the time during Stage I
operation,are presented in Table E.3.2.78.
Habitat areas expected to be equalled or
exceeded 90 and 10 percent of the time in under
the Stage I flow regime are also presented in
the Table.Similar values for natural flows are
also presented in the table for comparison.
These values are depicted graphically in Figure
E.3.2.78.Comparison of these values indicates
that the range of variation in the availability
of suitable spawning habitat for chum during
Stage I operation is less than the variability
observed for the natural flow regime.This is
due primarily to the reduction in flow variation
from week to week and from year to year during
the spawning period.Hence,although it is
anticipated that the total habitat area for chum
spawning in mainstem affected areas may be
reduced in the three Representative Groups,
spawning habitat area is expected to remain
relatively constant through the spawning period
and from year to year as was observed in the
analysis usi~g only the modeled spawning sites.
As described in Section 2.2.l.a,chum embryos in
mainstem affected areas are subject to
dessica.tionandfr.eezing.as aresuLto~f reduced
discharge in the river during the October and
November period prior to ice cover-formation.
Under Stage!project operation,discharge in
the middle river would be maintained at a
co-nsiderably greater discharge than under
natural conditions as indicated in Table
:E.3.2.73.As a result,embryos deposited in the
spawning areas are not expected to be as subject
...-·to-dessicatTonan:Cl"free-zTrig .(ADF·&G-I9-85h):--tri-
-----~f ac t-;-wate t-dep ElfS-a nCl----velcH:i:ti es -illtlle---~~---
spawning areas will be maintained at higher than
natural levels.It can be assumed that the
total spawning habitat area,as calculated using
the models and habitat criteria described above
and in Section 2.2.3,is also indicative of the
suitability-of·the area for incubation:If the
area is suitable for spawning,it is also
·--·suitable··forincubation of the embryos.Thus,
calculations of the spawning habitat areas for
discharges in October and November may be used
to evaluate the availability of the areas for
E-3-2-l52
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.•.}
-)
1
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851021
incubating embryos.Using this assumption,
estimates of incubation habitat loss or
reduction will be overestimated and estimates of
habitat gain will be underestimated.However,
this approach is useful as an index of the
effects of the altered flow regime or the
incubating embryos.Also,the use of open water
models to discuss incubation habitat areas under
project conditions can be justified,at least in
October and November,since it is expected that
the formation of an ice cover in the middle
river during project operation will not occur
until late November or December as discussed in
Exhibit E,Chapter 2 and when ice does form,it
will not progress as fa~upstream as under
natural flow conditions.
Total habitat area in the modeled sites
available for incubation in October and November
for the Stage I flow regime is presented in
Table E.3.2.79 and is depicted graphically in
Figure E.3.2.79.Values associated with the
natural flows are also presented for comparison.
Comparison of the Stage I values with the
natural flow regime values indicates that
suitable habitat areas fo~incubation will be
much higher under project operation than under
natural conditions.Hence,it is anticipated
that chum embryo survival will be enhanced .in
mains tern affected areas as a result of project
operation.
Similar results are obtained using the spawning
habitat response curve developed for
Representative Groups 2,3 and 4 (Table
E.3.2.48 and Figure E.3.2.63).Spawning habitat
areas expected to be equalled or exceeded 90
percent,50 percent and 10 percent of the time
in the three Representative Groups during Stage
I operation are presented in Table E.3.2.80 and
Figure E.3.2.80.Results of the analysis of
spawning habitat areas in Representative
Groups 2,3 and 4 for the natural flow regime
are also presented in the table.Again,the
total spawning habitat available for incubation
of chum embryos in these sites will be greater
with the Stage I operating flows than with the
natural flows.
.E-3-2-l53
851021
As discussed in Exhibit E,Chapter 2,Section
4.1.3,ice cover in the middle river is expected
to form later than under comparable natural
conditions.In addition,the ice cover will not
extend as far upstream.Thus,upstream of the
ice front,chum salmon incubation areas are not
expected to be affected by overtopping of the
upstream ends of the habitats as a result of
staging of mainstem water surface elevations
associated with the ice formation process.
However,downstream of the ice cover,staging
and,therefore,the probability that a site will
be overtopped by mains tern water will be greater
than under natural conditions (see Exhibit E,
Chapter 2 Sections 2 and 4.1 for a complete
description of the ice processes).The
,overtopping of a particular chum spawning/
incubation site'would adversely affect chum
embryo development (ADF&G 1983m,Wangaard and
Burger 1983).Hence,al though th ere is some?
gain in the expected survival of .chum embryos
~ueto ,tIle tnai:nt;ena:nce,of higher th,an natural
discharge in the river during the winter months,
the anticipated probability that si tes located
downstream of the ice front will be overtopped
could eliminate th.e ..anticipated gains.Overall,
in the absenc,e of mitigation measures"to protect
the peripheral habitats,survival of chum
embryos in mains tern affected areas would be lesstil-an under"na t1.I.r al-condItIo 05--:----
•Effects on Other Evaluation Species/Habitat
Combinations (**)
Baseline conditions in the reach of the Susitna
River within the Devil Canyon impoundment zone
will be altered as a result of the Watana
facilities-~-:"""Theprincipal'physica1""changes·wiH·
--~---------be--l;he-a-1-l;e·r-a·t-i:ou-o·f~l;he--f_l:ow--l."_eg-:i-meT-l."_educ-t-iau--,····-·
in the total suspended sediment loads during May
through September,moderation of the temperature
regime,and increase in the turbidity and
suspended sediment concentrations during the
winter months.In general,all of these regimes
wilLbechangedfrom exhibiting considerable
extremes in magnitude between summer and winter
..·,--coriditioris--to-relIlairii rig relat ivelycous taut
throughout the year.
E...,3-2-154
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851021
Adult salmon generally do not use this reach of
the Susitna River for spawning;however,a few
chinook salmon are able to negotiate the rapids
within Devil Canyon and up to 20 spawning pairs
have been observed in both Cheechako and Chinook
Creeks (ADF&G 1983e,1984h).In addition,five
to 10 individuals have been observed in Devi1's
Creek and one spawning pair has been observed as
far upstream as Fog Creek (ADF&G 1985b).
The absence of the other salmon species in the
Devil Canyon impoundment zone and upstream is
apparently due to velocity barriers at the rapids
within Devil Canyon.This is supported by radio
telemetry tracking results of chinook and chum
salmon adults and gill net captures of coho,chum
and pink salmon adults in the lower portion of
Devil Canyon.Radio tagged chinook and chum
salmon were tracked into the Devil Canyon reach
(ADF&G 1983m).These individuals subsequently
returned downstream to spawn.Movement of coho,
chum and pink salmon into the Devil Canyon reach
was demonstrated by the capture of adults of each
species at RM 150.2 and 150.4 (ADF&G
1983m).Presumably,these fish would have
returned downstream to spawn,since none has been
observed upstream of the lower rapids area at the
Devil Canyon dam site.It can be inferred from
these results that farther upstream movements of
adult coho,pink,and chum salmon are largely
blocked by the rapids.
Because of the somewhat lower flows in this reach
during Stage I operation,it is expected that the
number of chinook salmon able to negotiate the
rapids in Devil Canyon will increase.In
addition,it is possible that individuals of the
other species may be able to gain access to
spawning habitats in Devil Canyon.Hence,during
Stage I operation an expansion of the use of
habitats upstream of the Devil Canyon Dam site is
expected.
As discussed under the effects of Stage I filling
flows on other evaluation species/habitat
combinations,no adverse effects to the upstream
migration of adult salmon are expected as a
result of the altered flow regime.
E-3-2-155
851021
Chinook,coho,chum and pink salmon adults that
spawn in tributary habitats will not be affected
by project discharges in the middle river.
Sockeye spawning and incubation habitats will be
affected by project flows similar to the effects
to chum spawning and incubation described
previously.
Juvenile coho and sockeye move into upland slough
sites (Representative Group 1)which are not
affected to a large extent by mainstem
discharge.
Outmigration of juveniles of all salmon species
will not be affected by the altered flow regime
since there wiLl be sufficient discharge in the
river to accommodate outmigration.
Rainbow trout,Dolly Varden and Arctic grayling
generally move into tributary habitats during the
·st:illlfiferlllonths a.nd,th t=rt=fore,will not be
affected by the altered summer flow regime.
Since discharge in the river during the winter
months will be greater under projec t condi,t ions
than under natural conditions,it is expected
that more habitat with suitable conditions for
overwintering will be available for these
res i-dent -spe'cie's;-"'Some los s 0 f habitat may occur
in the reaches of the middle river that form an
ice cover.However,since the ice cover will
form later than under natural conditions and will
not extend as far upstream,it is expected that
rainbow trout,Dolly Varden and Arctic grayling
survival will be greater under project conditions
than under natural winter flows.Burbot
-_populatLons.in..the.mi ddleJ;"iyer_C!xe nQ~..E:!JCP-~<:ted
to be adversely affected by project operation
since they commonly inhabit-ieep~owvelocii:y
areas which will bt=maintained and possibly
increased under project flows.
Effects of Altered Temperature Regime (***)
Effects of the c:j.lteredtelllpera.ture!ice regimes
attributable to Stage I Watana operation may be
.,dIvl'dedInEo two·se'ason·s:the summer open water
period and the winter ice covered period.As with
the discussion of effects of the altered flow
regime,each of these seasons is discussed with
E-3-2-l56
)
1
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851021
respect to the average flow and temperature regime
expected during Stage I operation.
Water temperature during the summer months 1S a
function of discharge from the reservoir,
temperature of the water at the dam,climatic
conditions and distance downstream from the dam.
Estimates of water temperature at various locations
downstream were made using results of the
reservoir operations model for determination of
discharge;results o.f the DYRESM model for
temperature at the dam;and results of the SNTEMP
instream temperature model which integrates the
results of the other models with climatic
conditions to predict wa.ter temperatures at various
locations downstream from the reservoir (HE 1985a,
AEIDC 1984a,b,and c).The sensitivity of river
temperatures to extreme hydrological and
meteorological conditions and various project
operations is discussed in Exhibit E,Chapter 2,
Section 4.l.3(c)i:The selection of cases for
simulation is also discussed in that section.
Instream temperatures for the summer months were
estimated using 1981 and 1982 discharge and
climatic conditions.Summaries of the instream
temperatures at various locations for the period
May through October using 1981 and 1982 climatic
and flow conditions for the Stage I energy demand
are presented in Tables E.3.2.8l and E.3.2.82,
respectively.Tables E.3.2.83 and E.3.2.84
present comparable instream temperatures for
natural conditions.These estimates were based
upon the assumption that outflow temperatures were
to match inflow temperatures as nearly as possible
given the constraints for operating the temperature
control ports of the intake structure.The
assumptions for estimating instream temperature are
discussed in detail in Exhibit E,Chapter 2.
During the winter months,discharge from the Watana
Reservoir will be considerably greater under Stage
I of the project than under natural conditions
(Table E.3.2.73).At the dam,temperature of the
water will be between 1°C and 3°C depending upon
the water surface elevation in the reservoir
relative to which port in the intake structure is
being utilized at the time and the preceding
climatic conditions.As the water surface is drawn
down through the winter,discharge temperature will
E-3-2-l57
gradually decrease.However,when the water
surface elevation is low enough to require use of
the next lower intake port,the temperature of the
discharge water will increase by approximately 1°C
followed by another gradual decline.This pattern
is depicted in Figure E.3.2.81 for the period
November through April assuming the inflows and
climate for the 1981-1982 winter.
Once the water is released from the reservoir,
water temperature will decline to O°C at various
rates depending upon the air temperatures.As
depicted in Figure E.3.2.82,the zero-degree
isotherm will occur at various points within the
middle river depending upon the time 0 f year and
the particular climatic conditions.The depicted
location of the zero-degree isotherm assumes
climatic conditions observed during the 1981-1982
winter months and discharges from the reservoir
during Stage I operation.In general,during cold
periods,the zero-degree isotherm is located
further upstream"whereas during relatively warm
periods,the zero degree isotherm is located
further downstream.Once the river instream
temperature becomes DoC,formation of ice occurs as
described i~Chapter 2 of Exhibit E.The ice cover
will begin to form in the middle river in December
and will progress upstream to approximately RM 139
by theend'~o~fJanuary;The icecover-wHI .then
begin to recede through the remainder of the winter
as the amount of solar radiation increases during
the late winter and early spring months.It is
expected that the middle river will be ice free by
the end of April (a.s depicted in Figure E.3.2.82)•
Effects on aquatic habitats will occur during this
p-e_riJ~.c:i~.~H;.~L~e~J!..lJ:_..0 f~wgJ:;e r.~JlJ!.r.fa.~~..eleYEt::i,(>11
...~.._.__.___staging de scribed in Exhibi t E,Chapter 2.The---p--r--~=·nciple changes in the temperatures ~·andice-..~._-_~
regimes associated with operation of Stage I of the
Susitna Hydroelectric Project are:
o Summer river temperatures at the Watana Dam
will be up to 3°C cooler in May than under
,.natUra.l·condi:tions;nearly the same as
natural in June,July and August,and up to······1°c·warmer {Ii'October.
o Summer water temperatures at Portage Creek
(RM 149)will be approximately 2-3°cooler in
1
851021 E-3-2-158
,)
851021
May,approximately the same in June,July and
August and up to 4.5°C warmer 1n October.
o Summer water temperatures at the downstream
end of the middle river;i.e.near RM 99 will
follow the same basic pattern but the
differences from natural conditions will be
reduced (See Tables E.3.2.8l through
E.3.2.84).
o During winter months,from November through
April,water temperature at the Watana Dam
outlet will be I-3°C warmer than under
natural conditions (Figures E.3.2.8l)and
will remain above O°C for some distance
downstream (Figure E.3.2.82).
o An ice cover will begin forming in the middle
river in December,reach its furthest
upstream extencTin January and will likely
recede to somewhere downstream of the middle
river by mid to late April (Figure
E.3.2.82).
o Because water released from Watana Dam
throughout the winter will be between 1°and
3°C,water temperatures upstream of the ice
front will be a-3°C warmer than under natural
conditions •
•Effects on Principal Species/Habitat
Combinations (**)
Juvenile Chinook Rearing/Overwintering
Habitats (**)
As described in Section 2.2.l.a.i,juvenile
chinook begin to move into the mainstem as Age
0+fish sometime in June and July each year.
Age 1+fish,which overwintered in tributary
habitats also move into the mainstem.During
June and July,it is expected that water
temperatures in the mainstem will be nearly the
same as under natural conditions.Therefore,
rearing of juvenile ch inook in side channel
habitats in June and July is not likely to be
affected by project induced temperature changes.
However,because warmer water temperatures are
expected in the mainstem from August through the
end of October,it is expected that the Age 0+
E-3-2-l59
851021
juveniles will remain in side channel habitats
and continue to grow for a longer period than
under natural conditions.Once water
temperatures begin to decline to below 4°C,
juvenile chinook are expected to move into and
slough habitats to overwinter.It is expected
that juvenile chinook in the upper portions of
the middle.reach (RM 130-RM 150)will begin
moving to side sloughs somewhat later in the
fall than chinook juveniles in the reach
between RM 99 and RM 130.The difference in the
timing of the movement to overwintering habitats
is due to the differences in temperature between
the upper and lower portions of the middle reach
shown in Tables E.3.2.8l and E.3.2.82.
As a result of the extended warm water pe~iod in
the fall,it is expected that the juvenile
chinook will begin the winter,ice covered
period at .sizes similar to those attained under
natural conditions.An estimate of the
incremental increase in size cannot be made
given the.information which is available.It is
possible that the sizes of Age 0+fish in the
mainstem.affected areas (i.e.side channels and
side sloughs)may approximate those attained by
juvenile chinook in tributary habi tats (Table
E.3.2.l0).
During late fall,juvenile chinook move into
side channel and side slough areas that are
llorIllallyollly illdirec t1y af fec ted by mains tem
discharge and temperature.In side sloughs,
particularly,certain areas have water
tempera.tures which are greater than O°C and may
attain tempera.tures approaching 4°C (ADF&G
1983e,·1985a)due to the presence of groundwater
...····upwening~MaiiiEftemareas~Dy·c6rttraEft;·nave·
·~~_···-o~o·C~wa·t(;rr-temp·e·ra:ture-·from-p·rtor-:-t·o~·i~c·e~.
formation until breakup (R&M 1984,ADF&G
1983e).Circumstantial evidence pertaining to
the behavior of the fish during winter months
indicates that the juveniles overwinter in or
near the substrates in the upwelling areas
(ADF&G1983e,1983m,1984c;AEIDC 1984a,b ,c).
the s{de·sloughs,overwintering Juvenile
chinook may be affected by water temperature and
ice in the mains tem indirectly through the
E-3-2-160
. J
\ 1
j
851021
groundwater or directly as a result of the
staging of the mainstem water surface.
sufficiently to overtop the upstream end of the
sloughs.Increased water elevation (less than
that sufficient to overtop the upstream end of
the slough)tends to increase the rate of
upwelling in the sloughs and thereby provides
greater amounts of warm water (Exhibit E,
Chapter 2,Section 4.l.2(f)(ii».This,in
turn,increases the likelihood that juvenile
chinook will survive through the winter.
On the other hand,if staging of the mainstem
water surface is sufficient to overtop the
upstream berm,significant amounts of O°C,
mainstem water could be diverted into the
slough.At O°C,metabolic processes of the fish
may be sufficiently low to prevent the fish's
ability to maintain their positions in even
relatively low water velocity areas.Thus,_the
diversion of O°C mainstem water could cause the
juvenile chinook to be flushed out of the side
sloughs and,thus decrease their probability of
survival.Under natural conditions,mainstem
discharge is quite low during the winter
(1500-2500 cfs)and~staging due to ice formation
seldom attains sufficient elevations·;..to overtop"
the upstream ends of the sloughs.However,with
Stage I of the Project,mainstem discharge will
be considerably greater during the winter
(5,000-12,000 cfs between November and March).
Simulation of the ice formation process under
natural and Stage I conditions indicates that
more side slough and side channel sites will be
overtopped downstream of the ice front (Table
3.2.85)and overtopping will be of a greater
magnitude than under natural conditions.
However,upstream of the ice front,staging due
to ice cover formation will be less under Stage
I than under natural conditions because no ice
cover is expected to form under Stage I flow and
temperatures.
Hence,the survival of juvenile chinook in all
side slough habitats in the winter months is
expected to increase as a function of the
increased rates of groundwater upwelling in the
sloughs.However,without mitigative measures,
this gain is countered by potential loss of the
habitats resulting from more likely overtopping
E-3-2-161
851021
of the upstream ends of the sloughs and
diversion of DOC mainstem water into sloughs
downstream of the ice front.
In summary,altered temperature and ice regimes
attributable to operation of Stage I of the
Susitna Hydroelectric Project are expected to
have the following effects on juvenile chinook
salmon:
o Delay in the onset of the summer rearing
in the mainstem due to lower than natural
(.water temperature ~n May.
o Prolongation.of the summer rearing period
in the fall due to the persistence of
warmer water temperatures into the fall.
o Increased overwinter survival due to the
delay in the formation of an .ice cover and
higher mainstem discharge which maintains
higher rates of warm groundwater upwelling
I:nihe snie sloughs.
o The greater likelihood of overtopping of
the upstream ends of side sloughs due to
ice formation and cover will cause'loss of
juvenile chinook salmon from the side
sloughs if no mitigation efforts are taken
t::0 p~ot::e Ctt::he seJ:1 ab it::a ts~~-~
Chum Spawning/Incubation Habitats (**)
As described in Section 2.2.2.a.iv,chum
spawning occurs in August and September of
each year in side channels,side sloughs and to
some extent mainstem·habitats.During this
period,~~mainste:m~~temperature·wil~l··be
---~_.app,~ox-ima.te~l.y--the--s.ame-under-~S.tage-~I~-ofthe--~..~~--
Project as under natural conditions.Thus,the
principle factor governing the availability of
spawning habitat is mainstem discharge as
discussed in the previous section and no affects
due to an altered summer temperature regime are
c~p~e~c:t:~dcl:u,J::itlg S_ta,ge I operation.
Inc ubationof..chum ~embryos in the various
habitats begins with deposition of the eggs and
continues through emergence of the fry from the
gravels in March and April each year.During
E-3-2-l62
'j
1
1
r
851021
this period changes in the winter temperature
and ice regimes will affect the survival rates
of the chum embryos.
Under natural conditions,winter mortality of
chum salmon embryos have been estimated in both
field and laboratory conditions (ADF&G 1984c,
1985c;Wangaard and Burger 1983).Survival of
chum salmon embryos from egg deposition to
outmigration of the juveniles is estimated to be
12 to 14 percent (ADF&G 1984c).This estimated
mortality is based upon the total estimated
number of eggs deposited in tributary,side
channel,side sloughs and mainstem habitats and
the estimated total number of outmigrants from
the middle river.
The causes of chum embryo mortality may be
partitioned to some extent to account for
effects of temperature and ice processes on
survival in side sloughs and side channels.
Mortality rates of Susitna River chum embryos
were estimated as part of a laboratory study of
the effects of temperature on development
(Wangaard and Burger 1983).Chum embroys were
inc1,1bated under four di fferent temperature _
regimes varying from averages of 2°C to 4°C,
similar to regimes encountered in the field.
Because of-the controlled conditions,the
observed mortality rates of 2-5 percent are
attributable either to the temperature or to
some other biological factor not associated with
the physical environment (i.e.disease,lack of
fertilization,genetic disorder,etc.).It is,
therefore,safe to assume that an approximate 5
percent mortality of chum embryos in the field
situation could be attributable to similar
causes.Because of the nature of environmental
conditions,it is safe to assume that much of
the remaining mortality of chum embryos is
attributable to physical processes in the
habitat.
TWo principal physical factors which could
account for a significant portion of the
estimated mortality are associated with mainstem
flow influences on the spawning habitats which
are in turn affected by ice processes in the
river.The two factors are;1)dessication and
freezing of the embryos due to the reduction of
E-3-2-l63
851021
mainstern discharge prior to ice cover formation
(ADF&G 1985a);and,2)reduced temperature in
the spawning areas resulting from staging of the
mains tern water surface and overtopping of the
upstream ends of the sloughs.Mortality due to
dessication and freezing was discussed
previously under the effects of the altered flow
regime.
When the upstream ends of side channels and side
sloughs are overtopped as a result of ice
formation and water surface staging,DoC water
is diverted into the channels and may cause
water temperatures in the substrates to decline
to near DoC.Depending upon the developmental
stage of the embryos at the time of an
overtopping event,the DoC water may cause death
of the embryos or may cause developmental
abnormalities to·occur (Wangaard and Burger
1983).Laboratory studies of salmon
developmental rates vs.temperature indicate
that sockeye embryos are especially sensitive to
thermal (cold)stress early in the developmental
process (Velson 1980,Barns 1967,Combs 1965).
Although not documented for chum embryos,it is
likely that the embryos are also susc.eptable to
low water temperatures during the early
developmental period.The increased mortality
and--deve-lopmenta-l-abnor.mal i ty ra-tesobserved by
Wangaard and Burger (1983),were.corroborated in
the middle SusitnaRiver'by observation of large
numbers of dead embryos,reduced fry size and
higher frequency of abnormal ities in Slough 8A
following an overtopping event in 1982 (ADF&G
1983m).Embryos in other sloughs which were not
overtopped did not exhibit the large number of
_.__._.~d::.e,a d em b z::~o~_()t:'!i1:>.1l:l:>..r tIlli ~.~EY.'
In contrast totne tnree '-facTors ais-c us sea'
above,a fourth factor,the effects of staging
on groundwater upwelling rates,likely
contributes to the survival of chum salmon
embryos.Upwelling groundwater benefits embryo
development by providing higher water
.temperatures -(2°C-4°C)in the spawning gravels,
more constan.t:dissolved oxygen concentrations,
....-.."arid remoValOffi"nesedimertts which may have a
detrimental effect on embryo survival.
Upwelling rates are at least partially dependent
upon mainstem water surface elevation (Exhibit
E-3-2-164
.1
I 1
·"1'-'1
\)
.1
.]
'r
851021
E,Chapter 2,Secitons 2.4.4 and 4.1.2(f)(ii»
and staging of mainstem water caused by the ice
formation processes results in increased
groundwater upwelling rates which in turn
contributes to the survival of the embryos.
In summary,several factors associated with
winter flow and ice processes in the mainstem of
the Susitna River under natural conditions
affect the survivorship of salmon embryos during
the incubation period.Factors which tend to
decrease survival are:
o Reduced mainstem flow resulting in
dessication or freezing of the salmon
embryos;and
o Overtopping of the upstream ends of
sloughs and side channels diverting the
O°C water in to the sloughs and side
channels causing thermal (cold)stress to
the embryos.
A factor which tends to increase survival of
embryos is increased groundwater upwelling and
maintenance of higher water temperatures in the
gravels.
The changes in water temperature during winter
months resulting from operation of Stage I of
the project will have several effects depending
upon the particular location of the
spawning/incubation areas.As discussed
previously under the effects of the altered flow
regime,increased mainstem discharge will
maintain groundwater upwelling rates in the
sloughs at a higher level than under natural
conditions.Therefore,the warm groundwater
temperatures will be maintained in the slough
spawning areas and will increase the survival of
chum embryos through the winter months.
An adverse impac t of the higher discharges
during the winter is that in those areas in
which an ice cover will form,mainstem water
surface staging will likely be sufficient to
overtop the upstream ends of the sloughs,
thereby diverting aoc water into the areas
having incubating chum salmon embryos.As
discussed with respect to juvenile chinook
E-3-2-165
/
851021
overwintering areas,the magnitude of
overtopping will be greater than under natural
conditions and may penetrate into the substrates
sufficiently to.retard developmental rates.
Retardation of chum embryos development rates
due to lower temperatures has been demonstrated
both in the laboratory (Wangaard and Burger
1983)and in the field (ADF&G 1983e).The
influx of O°C water could also increase the
mortality of chum embryos in the side slough
substrates.However,because the progression of
the ice front into the middle river will occur
2-4 weeks later than under natural conditions,
it is likely that chum embryos will have
developed sufficiently such that the influence
of O°C water will not affect development or
mortality of chum embryos significantly.Also,
some portions of the middle river will not have
an ice cover or the duration of the ice cover
will be considerably reduced such that
overtopping events will ei ther not occur or will
be .relatively short in duration (see Figure
E.3.2.82 and Table E.3.2.85).
In summary,the major impacts to chum spawning
incubation due to temperature and ice process
changes associated with Stage I of the Project
are as follows:
o Chumspawlliilg in side channels ana side
sloughs will be unaffected by mafnstem
water temperature.
o Chum embryo survival and development will
be benefitted by the extension of warmer
water conditions into the fall.
·······-··o--Maintenanceof ...g roundwal:er-upwelli·ng·rates···
.-----__-th·r,.ou·gh-:the__wcinte.r-.-wi.l-l--pr-event--fr.eeztng.._...._-
of the chum embryos.
o Potenti~l adverse effects to embryo
development and survival associated with
overtopping of the sloughs may be greater
...tll.a_n...:u1'!g~rll~tural conditions •However,
delay of ice·formation in the middle reach
~y_.~llevia:te.potentia:Ladverse effects of
O°C water on embryo development and
survival.
E-3-2-166.
.•...•..........•.__..•__._----.•......_-.-._-_..__..-.-_._..~'.'...•..
~']
.1
I
't
\
1
)
o The dispersal of the ice cover earlier in
the spring and the influence of.somewhat
warmer mainstem temperatures in April may
enhance the survival of chum fry after
they emerge from the gravels.
Other Evaluation Species/Habitat
Combinations (***)
The impact of the altered temperature and ice
regimes in the middle Susitna River resulting
from Stage I operation on other evaluation
species/habitat combinations are summarized
below.
Since chinook migration occurs during July in the
middle river and the estimated temperatures under
Stage I operation are nearly the same as under
natural conditions,no effects are expected.
Chinook spawning/incubation occurs in tributary
habitats and therefore,will not be affected by
the mainstem temperature and ice regimes under
Stage I conditions.
Sockeye migration
early September.
temperatures will
occurs in late July,August and
The minor change in mainstem .
not affect sockeye migration.
851021
Sockeye spawning and incubation occurs almost
exclusively in side slough·habitats under nearly
identical habitat conditions used by chum salmon
(ADF&G 1983k,1983n,1984b,EWT&A and wee 1985.)
Therefore,the impacts of temperature and ice
regime changes are the same as those described
for chum spawning and incubation.Sockeye
juvenile rearing and overwintering habitats
include side sloughs and upland sloughs.The
impacts on sockeye juveniles rearing and
overwintering in side sloughs are essentially the
same as those described for juvenile chinook in
side sloughs.Upland sloughs are generally
unaffected by water temperatures in the mainstem
during the summer and winter.Therefore,the
anticipated temperature and ice regime changes
under Stage I conditions are not expected to
affect juvenile sockeye in upland sloughs.
Outmigration of juvenile sockeye from the middle
river generally occurs in June and July (ADF&G
1983m,1984c).Since water temperature at this
E-3-2-167
time would be similar to natural conditions,no
effect to outmigration is expected.
Upstream migration of adult coho salmon generally
occurs during August and September in the middle
river.Since water temperatures are expected to
be nearly the same as natural at this time,no
adverse effects are expected.Coho spawning and
incubation occurs in tributary habitats and,
therefore,will not be affected by al tered
temperature and ice processes in the mainstem.
Most juvenile coho rearing occurs in tributary
habitats (ADF&G 1984c).Therefore,no effects
due to mainstem temperature changes are expected.
A few.juvenile coho move out of the tributaries
and in to upland sloughs for rearing and
overwintering.Again,these habitats are not
influenced by mainstem temperature and ice
processes and,therefore,no project-induced
temperature impacts on coho juveniles are
anticipated.
Outmigration
ri ver occurs
tempera tur es
Project will
conditions.
anticipated.
of coho juveniles from the middle
in June and July when water
under Stage I operation of the
be nearly the same as natural
Therefore,no impac ts are
851021
Upstream migration of adult chum and downstream
outmigration of juvenile chum occurs in July and
August;and June and July,respectively,when
mainstem temperatures are expected to be nearly
the same as natural conditions.Therefore no
impacts are expected as a result of Stage I
project-induced changes in water temperature.
Upstream mIgrat::Ion-of pInk salmon occurs in July
~~a-n~d-August at atime When projei:tTnduceClcl:ianges·-
in water temperatures are similar to natural
temperatures.Mos t pink.salmon spawn in
tributary habitats where incubation of the
embryos are not affected by mainstem temperatures
during the winter months.For the few pink
salmon which-do spawn in side sloughs habitats,
··the Impacts on incubating embryos will be the
.-clfam:e'as~-tli(H3-edesc·riDedfor chum embryos.
Outmigration of pink juveniles normally occurs in
May and early June.under Stage I operating
E-3-2-168
I
.)
851021
conditions,mainstem temperatures will be up to
2-3°c less than under natural conditions.This
could result in a delay in the outmigration of
juvenile pink from the middle river.However,
since the outmigration of pinks appears to be
closely associated with breakup of the ice cover
under natural conditions,the cooler temperatures
may not affect the outmigration of the
juvenile s.
Utilization of mainstem and mainstem affected
habitats by rainbow trout,Dolly Varden and
Arctic grayling generally occurs from late summer
through the winter months into early spring.
During these periods,mainstem water temperatures
are expected to be greater than natural
conditions except the reaches of the river
downstream from the O°C isotherm in mid winter.
In this reach,water temperatures will be,the
same as under natural conditions.The
predominance of somewhat ..warmer water
temperatures in the mainstem through the winter
months should enhance winter survival of these
populations and could result in increased winter
growth assuming an adequate food supply.
However,the enhanoement may be offset by higher
than natural turbidity levels 'as discussed in the
following section.
No major effects to burbot populations are
expected as a result of the anticipated changes
in temperature and ice regimes associated with
Stage I operating conditions.
Effects of Changes in Suspended Sediment
Regime (***)
Water released through the turbines at Watana Stage
I will be drawn from five,vertically spaced
intakes placed between elevations 1,800 and 1,980
ft MSL.In general,the uppermost and,therefore,
generally,the least turbid and highest quality
reservoir water will be used for power generation
and consequent discharge to downstream habitats.
Stage I operation flows will be increasingly larger
as power production increases and new generation
units come on line.Because of the relatively
smaller Stage I reservoir storage volume,summer
flows may be approximately 4,000 cfs greater,and
winter flows about 2,000 cfs less than those
E-3-2-169
originally proposed for the two stage project.
Stage I operational flows will be maintained within
the Case E-VI flow constraints.
A major consequence of the al tered suspended
sediment which will have potentially positive
biological effects in all riverine habitats
affected by mainstem flows will be flushing and
removal of the finer sediments in the streambed.
Removal of fine sediments (sand and silt)should
almost always be expected to improve streambed
habitat for aquatic organisms at all trophic -
levels.Because of greatly reduced suspended
sediment loads in all project flows,re-deposition
on and within streambed substrates will be
substantially reduced in most riverine habitats
downstream of the project.Estimated changes of
suspended sediment concentrations and turbidity
values during Stage-I operations have been made
(Table E.3.2.86.)
Few other biologically important effec ts di fferent
from the natural situation are expected to occur in
relatively deep (great~r than 1 to 2 ft.)mainstem
habitats of the middle reach during the open water
seasons of Stage I operations.In peripheral
habitats,two potentiaL beneficial -effects of Stage
I Operations will be less flooding and greater than
n~t:1,1~.51l.flQ~f:lt~l:>il~t:Y.__Th~former two effects.maY
result in greater than naturaibiomass -productivfty
at all trophic levels in predominantly clear water
habitats and in very shallow turbid habitats during
the open wa ter seasons.
Incident illumination.reaching stable streambed
substrates may increase during the open water
season,especially along the edges of the mainstem
arta-it'l-snallowri:verine-habi:tats peripheral to the--
---..-----------~--..---~---.---~-----------------~~-ma_i_nstem.--·--However.,-cont-i-nuous-ly-h-i-gh--~ut'--bi_di_~y-·i-n-
relatively deep (greater than 1 to 2 ft.)mainstem
habitats may eliminate or substantially minimize
the spring and fall periphyton growth periods and
the consequent fall and winter epilithon standing
crops which have been observed under natural
.conditions.•'.--
Inwintet',·~illcidellt light reaching stable mainstem
streambed substrates will be reduced when compared
to natural.An unquantifiable duration and rate of
primary productivity and an unquantified
-1
.!
851021 E-3-2-l70
851021
epilithon standing crop which naturally occurs
during the clear water,winter season in.many
middle river mainstem habitats may be absent or
considerably reduced during the Stage I operational
phase.In fall,winter and spring the invertebrate
processing 0 f epilithon and alloch thonous organic
materials will be affected in unknown ways by fine
inorganic particulates released from the upstream
project.Resultant changes at the detritivore and
primary producer trophic levels will have unknown
effects on rearing invertebrates and the fish
utilizing these food sources.Some habitats may be
affected positively and others negatively with
respect to lower trophic level biomass production.
The net cumulative effects may remain similar to
the natural situation,but may require more than
one annual cycle to stabilize.
Light to moderate "dusting"of stable substrates
with fine glacial flour particulates may have a
fertilization effect,particularly where incident
sunlight will allow photosynthesis.Esp~cially in
relatively warm,low velocity habitats,
sedimentation of rock flour particulates may
stimulate profuse periphyton growth and epilithon
standing crops.Analagous situations ..have been
observed on another south central Alaskan river
which is chronically turbid (Kasilof River).
Turbid mainstem discharges caused to overtop
peripheral habitats containing incubating eggs and
larval fish,if the organisms are not protected by
relatively warm and clear,upwelling ground water,
may cause detrimental effects to the developing
organisms.Effects will depend,at least in part,
on the organism,its life stage and the amount of
rock flour deposition.
Ice related staging of cold,turbid winter dischar-
ges into peripheral habitats or any habitats used
by juvenile or rearing/overwintering fish is not
expected to cause direct,detrimental effects to
the fish.Particulate concentrations of Stage I
Operational discharges may be stressful,but are
not expected to be lethal to juvenile salmonids.
Altered suspended sediment regimes during Stage I
Operations are not expected to detrimentally alter
access to,or use of tributaries.Clear water
upwellings and clear water tributary plume habitats
E-3-2-l7l
851021
will likely become more important to rearing and
overwintering fish in the middle river..
-Effects of Other Water Quality Changes (***)
Except for the changes in suspended sediments and
turbidity,anticipated water quality changes are
not expected to significantly alter habitats
affected by Stage I flows in mainstem riverine
habitats within the middle reach,with respect to
the biotic community.High chronic turbidity will
substantially restrict reservoir and mainstem
riverine habitat euphotic zones thereby minimizing
any detrimental effects due to project induced
changes in nutirent concentrations.No bilogically
detrimental oxygen concentrations are expected for
either the surficial depths of the reservoir or for
riverine habitats downstream.The project is not
expected to cause biologically detrimental
concentrations of dissolved nitrogen in either
reservoir or riverine habitats downstream.Basic
changescinwaterchemistry which are expected to be
caused by the project are not expected to be
detrimental to fisheries in either the reservoir:or
downstream aquatic habitats (see discussions of
water quality in Exhibit ..E,Chapter 2).
(iii)Talkeetna to Cook Inlet (***)
-Effects of Altered Flow.Regime (***)
Discharges in the lower river will be affected in a
manner similar to that described for the middle
river.However,the proportional reduction in
discharge during the summer months will be less due
to the influence of maj or tributary contributions
to the lower river discharge from the Chulitna,Talkeetna "and "'renfna Rivers";"as .welT .ifsotner-
~-sma I Ier tr iout::arie s •Avera"g-er-rifonth-ly""d"i-s"ch"arge
during Stage I operation at Sunshine and Susitna
Stations are presented in Exhibi t E,Chapter 2,
Section 4.L3.a.A summary of the maximum,minimum
and mean average monthly flows for natural and
Stage I operation in 1996 and 2001 is presented in
TableE.3.2 ..87for·theSunshine Station and Table
E.3.2.89 for:the Susitria Station.
E-3-2-172
)
851021
•Effects on Principal Evaluation Species/Habitat
Combinations (***)
Juvenile Chinook Rearing Habitat (***)
The effects of the Stage I operating flow regime
on chinook rearing habitats are evaluated
based on the monthly average discharges at
Sunshine in comparison with the habitat response
curves for side channels complexes,and
tributary mouth habitats presented in Section
2.3.1.b.iii.The curves presented in that
section are aggregated into two curves
representing side channel/side slough habitats
(Figure E.3.2.83)and tributary mouth habitat
(Figure E.3.2.84).The method for aggregating
the individual curves is not the same as
described fo~-the middle river Representative.
Groups,since these curves represent the -
response of habitat quality in the sites and do
not represent total habitat area.However,the
curves may be used in a qualitative manner to
evaluate anticipated changes in lower river
chinook rearing habitat in side channel
complexes and tributary mouths resulting from
Stage I operation.
During the period June through September,
chinook rearing habitat in side channels and
side sloughs is expected to improve slightly
over natural conditions.This is indicated by
comparing the habitat quality values,estimated
from Figures E.3.2.83 and E.3.2.84,at the mean
average monthly flows in June,July,August and
September for Stage I operation demand years
(Table E.3.2.87)with the habitat quality values
at the mean average monthly flows under natural
conditions.The estimated habitat index values
for the mean monthly discharges at the Sunshine
Station are presented in Table E.3.2.89.
Habitat quality in tributary mouth habitats is
expected to decrease to some extent during Stage
I operation.Since considerable numbers of
chinook juveniles inhabit tributary mouth
habitats in the lower river,the expected
reduction could be considered to be significant.
However,a limitation of these curves is that
the habitat qualities are a function of both
mainstem and tributary discharges.Hence no
E-3-2-173
851021
values for the habitats are available when the
tributary discharge is high and mainstem
discharge is low.Hence,the apparent loss is
not expected to be as great as that indicated in
the available data.
Juverti1e chinook are expected to be less
susceptible to overwintering mortality because
of the greater mainstem discharges in the river.
The higher survival rates of overwintering
chinook juveniles is expected for the same
reasons described in Section 2.3.1.c.ii for
middle river habitat effects.
Chum Spawning Habitats (**)
As discussed in Section 2.3.1.b.iii,few chum
salmon spawning areas are known to exist in
lower river,mainstem-affected areas,
specifically in the side channel-side slough
complexes.Therefore,changes attributable to
Stage I operation are not expected to
significantly affect chum spawning activity in
habitats associated with the lower river •
•Effects of Other Evaluations Species/Habitat
Combinations'(**)
O...c-A1-teri-ng-o·f--the-·lowet'rivet'dischat'ge regime as a
result of Stage I operation is not expected to
significantly affect other species/habitat
combinations.
Discharge in the lower river will be sufficient
to accommodate upstream migration of adult salmon
since they are able to migrate under a wide range
conditions.
-"----------------.--------·Since--few---sa Imon -~are '-known-to--s-p-awri-In-----rOwtir~---
river mainstem associated habitats,incubation of
embryos will not be affected significantly.As
discussed for the middle river,increased
discharg~in the lower river during the winter
months is expected to increase the survival of
those embryos which do incubate in lower river
habitats.°
Rearing of juvenile salmon in lower river
habitats is not extensive (ADF&G 1985c and
Section 2.2.1.a).Hence,rearing habitats in the
E-3-2-174
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851021
lower river are not expected to be significantly
affected by the altered flow regime.
As discussed in Section 2.3.l.b.iii,rainbow
trout,Dolly Varden,Arctic grayling and burbot
populations using lower river habitats are not
expected to be adversely affected by the altered
flow regime during Stage I operation.
-Effects of Altered Temperature/Ice Regimes (***)
As discussed in Section 2.3.l.c.ii,water
temperature at.Talkeetna is expected to be
approximately the same under Stage I operating
conditions as under natural conditions.The only
difference anticipated is that progression of the
ice front upstream during the winter·months may be
somewhat slower and reach Talkeetna 2-4 we_eks later
than under natural conditions.Therefore,no
impacts,either beneficial or adverse,on salmon,
other anadromous species or resident species using
mainstem or mainstem associated habitats are
anticipated as a result of project induced changes
to the temperature and ice regimes in the lower
river.
-Effects'of Altered Suspended Sediment (***)
The e.f fec t 0 f chronically turbid flows from Stage I
Watana Reservoir operations on lower river habi-
tats are expected to be similar to those effects
occurring in the middle river reach.In the lower
river reaches,however,dilution by additional
tributary influents is expected to lessen most
project induced effects (refer to previous
discussions of water quality changes in Exhibit E,
Chapter 2).
Below Talkeetna,waters from the middle river reach
will mix with other tributary flows from the
Chulitna,Talkeetna,Kashwitna,Yentna and other
tributaries.Because of these dilution effects,
project discharges will not demonstrably alter
suspended sediment concentrations,turbidities,or
riverine biology during the May through September
period of open water flows in lower river
habi ta ts.
During the naturally clear water season,October
through April,turbid waters flowing beyond the
E-3-2-175
middle river reach will mix with clear,non-turbid
water from major tributaries.The dilution from
clear tributary influents will help maintain
chronic winter suspended sediment concentrations
within levels which may be stressful,but which are
not expected to be lethal,to overwintering fish.
The effects of chronically high suspended sediment
concentrations on lower trophic level biological
activities in mainstem and peripheral habitats in
the lower river will be similar to those described
for the middle river reach (See Section
2.3.l(b)(ii).Tributaries to the lower river reach
will not be impacted by Stage I operational flows.
-Effects of Other Water Quality Changes (**)
Other water quality changes resulting from Stage I
operations are not expected to cause biologically
important effects on mainstem,peripheral or
tributary habitats in the Talkeetna to Cook Inlet
reach (see previous discussions for Stage I
construction and operation and discussions of water
quality in Exhibit E,Chapter 2).
(iv)Cook Inlet Estuary (***)
Low suspended sediment concentrations and low
...turc.bi-di.ty~are-expec.ted.~to.center .the·Cook.Lnl.et
estuary on a continuous basis due to Watana Stage I
operation.No important biological effects other
.than mild fertilization are anticipated.Because of
strong currents and high ion concentrations in the'
inlet,riverine borne particulates will be relatively
rapidly dispersed,diluted and precipitated.
(d).Sunnnary of Impacts Associated with Watana Dam (**)
The primary long-term aquatic impact related to
construction of Stage I Watana Dam will be the
increase in harvest pressure resulting from the
increased access afforded by the project roads.In
the absence of stric ter harvest regulations,the
increase.in access near the impoundment could cause
substantia I al teratidnlf itfreS ident fish popul a tion
structure,with the present population of large,
older grayling being replaced by younger
individuals.
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851021 E-3-2-176
851021
There will be an alteration of aquatic habitat at
stream crossings but with proper construction
practices as discussed in Section 2.4.3,this impact
is not expected to noticeably affect fish
populations.Construction activities and reservoir
clearing activities will cause temporary increases in
siltation and turbidity in some of the project area's
clear-water streams.These impacts are not expected
to extend beyond the construction period.Similarly,
alterations in water quality and disturbance to fish
populations are expected to impact fish only during
the construction period.There will be a continuous
possibility of fuel spills during the construction
period when numerous construction vehicles are
present in the project area.The possibility of
acute spills will be reduced under operation,but the
potential for spills will continue for the life of
the project.Acute spills could cause locally
significant impacts to fish populations,while
chronic spills wi 11 affect habi.t:at quality.,
particularly along roadways.
Borrow Site E,at the mouth of Tsusena Creek,will
convert riparian and upland habitat into aquatic
habitat.The newly-formed lake will have potential
as a productive feeding and overwintering area for
resident fish,but rehabilitation measures for this
borrow site will not be undert~ken until Stage III is
completed.
(ii)Filling Impacts (**)
The primary long-term impact associated with the
filling of the Watana reservoir is the loss of
clear water tributary habitat.The tributary habitat
that will be inundated by Stage I development
currently supports a substantial population of
grayling,estimated to be at least 9,140 (Table
E.3.2.24).Aquatic habitats within the reservoir are
not expected to support a significant grayling
population (Section 2.3.l.b.i).
Between Watana Dam and Talkeetna,the primary impacts
associated with filling will be a reduction in spring
and summer flows,reduction in sediments,and an
altered temperature regime.Mainstem and
side-channel habitats will contain less turbid water
and be subjected to less extreme fluctuation in water
levels and flow during the summer.These changes are
expected to provide more favorable fish habitat than
E-3-2-l77
now exists in these areas.During filling,effects
on juvenile chinook rearing habitats and chum
spawning habitats are not expected to be impacted by
altered water temperatures,primarily because it is
expected that summer river temperatures will be
nearly the same as natural conditions.Similarly,no
project induced effects on juvenile chinook
overwintering habitats in the side sloughs or chum
incubating areas is expected during the first winter.
This is due to the expectation that water temperature
and ice processes will be similar to natural
conditions.
Slough habitats between Watana Dam and Talkeetna are
expected to be·the habitat type most significantly
affected by filling flows.In the absence of
mitigation features,filling flows are expected to
cause access problems for returning adult chum and
sockeye salmon.For salmon that do gain access,the
spawning area within tqe sloughs may be reduced in
area because of the lower mainstem flows (see Section
2.3.l.b.ii).If un-mitigated,these impacts would
reduce the number of spawning chum and sockeye salmon
in the sloughs above Talkeetna.However,with
proposed mitigation measures (see Section 2.4),it is
expected that these populations will be maintained.
Tributary habitats below Watana Dam and all habitats
below 'I'alke~tna.are notex1>ect~d tobe significantly
i~p~cted d~ring the fi(lin:~fthe Watana reservoir
(Section 2.3.1.b.ii and iii).
(iii)Operation Impacts (**)
operation impacts,as with filling,are divided into
impacts due to the impoundment and downstream
,impacts.
_..-----------------------.-.----------.--_·----.--The--habi-ta·t-w±th-in--'the-W·at-ana-reser-vo·i-r-is--noe---------
expected to support substantial fish populations
(Section 2.3.1 c.i).The annual drawdown cycle will
limit spawning habitat of grayling,lake trout,
burbot,white fish and longnose sucker.Littoral
rearing habitat is also not expected to be productive
because.ofthedrawdowncycle and summer turbidity
levels and suspended sediment concentrations.
--Gray--iing -are,-expecEedtoreside--at t:hemouths-of the
tributaries.Lake trout and Dolly Varden are
expected to develop small resident reproducing
populations within the reservoir.However,the
1
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851021 E-3-2-178
851021
population is not expected to increase sufficiently
to form a significant sport fishery.Other species
are expected to migrate into the reservoir from
upstream habitats,primarily to overwinter,and may
establish small resident populations.
Between Watana Dam and Talkeetna,the primary
operational impacts will be similar to those
discussed for filling:decreased summer flows,
decreased flow variability and decreased sediment
load.During winter,however,flows will increase
over pre-project conditions and will be accompanied
by increased temperature,turbidity,and suspended
sediment concentrations.
More stable summer flows and decreased sediment loads
and turbidity are expected to improve summer rearing
habitat in mainstem and side-channel habitats.
Eventually,-mainstem and side-channel spawning
habitats are expected to become available as the
project flows remove accumulated sand and sil~
deposits and maintain the upper level of the
substrate in clean condition (Section 2.3.1(c)(ii).
Case E-V1 flow constraints,implemented during Watana
Stage I fi lling,will be followed.These cons traints
plus the mitigation measures already implemented
during Watana -Stage I construction are expected to
maintain the number of chum and sockeye salmon
spawning in the sloughs ups tream from Talkeetna.The
worst case scenario would be total loss of slough
spawning habitat in this reach,with a reduction in
the total run size.
The increase in winter flow is expected to increase
overwintering habitat and will benefit resident and
rearing anadromous species.The reduction of flow
variability,peak flows,turbidity,and sediment load
in the mainstem during summer combined with increased
winter flow may lead to increases in the populations
of some resident species such as rainbow trout and
Dolly Varden;and rearing anadromous species such as
chinook and coho salmon.The amount of increase,if
any,will depend on the extent to which these physi-
cal factors presently limit the populations.
The increased winter temperatures may increase embryo
development in mainstem and side-channel spawning
habitats and lead to early emergence of alevins.
These early emerging fry may experience increased
E-3-2-179
mortality if they move downstream and encounter O°C
(32°F)water below Talkeetna.This impact will likely
affect relatively few fish,primarily pink salmon,
since only a small portion of the salmon spawning
upstream from Talkeetna utilize mainstem and
side-channel spawning habitats.Other salmon species
using these habitats exhibit behavior patterns that
reduce their vulnerability to these impacts (Section
2.3.1.c.ii).Impacts are not expected in tributary
habitats upstream from Talkeetna.
Downstream from Talkeetna the main impact will be an
increase in overwintering habitat in the mainstem and
side channels because of the increased winter flows
(Section 2.3.1.c.iii).No significant adverse
impac ts are expec ted.
2.3.2 -Anticipated Impacts to Aquatic Habitat Associated with
Stage II Watana/Devil Canyon Dam (***)
Stage II of the Susitna Hydroelectric Project conSi.ists of .the
cons truction of·the Devil Canyon Dam to supplement the power
generation capacity of the Stage I Watana Dam.In general,the
construction and operation of the Devil Canyon Dam will be as
de scribed in the original License Application (APA 1983b).The
principal differences between the Stage II configuration and the
original configuration will be that the Watana Reservoir will
have a maximum normal operational water surface elevation of
----2~,000-~feet -MSL -r-ather.-thalL_2,185_fee.t__MSL.,,the ,,1Lv:.e_s_toxage_wiU__
be reduced from 3.7to 2.4 million acre-feet,and the flow regime
during construction and operation of Stage II will operate under
the Case E-VI flow constraints rather than the Case C scenario
described in the original License Application.This section
addresses additional impacts on the aquatic resources
attributable to the development of the Devil Canyon Dam,assuming
the Stage I Watana Dam is operating.
--{aT"-c-onsEruc iron'of DevilCariyoii15am (Stage--Il)arid ReHrte-d
--_._-~,_._------~..Fac i lif ies (~)
(i)Devil Canyon Dam (Stage II)(*)
Devil Canyon Dam will be located at RM 152 of the
Susitna River,approximately 32 miles (53 km)down-
streamfrom-the--Watanadamsi-te.A thin arch concrete
dam wi 11 be buil t near the downs tr eam end 0 f Devi I
Canyon andan'earth/rockfillcsaddle dam will be
constructed at the south end of the arch dam to
provide closure of a low area on the south abutment.
The reservoir behind Devil Canyon will cover 7,800
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851021 E-3-2-180 I,J
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851021
acres (3,120 ha)and will be about 26 miles (42 km)
long (32 miles along the river before impounding)and
not more than 0.5 mile (0.8 km)wide.
The concrete dam and foundation will be 646 feet
(195 m)high and will have a crest length of 1,650
feet (503 m).An estimated 1.7 million cubic yards
(1,300,000 m3 )of concrete will be needed to
construct the arch dam.The saddle dam will be 950
feet (287 m)across and 245 feet (75.m)high and will
require about 2 million cubic yards of material.
As with Watana,Devil Canyon Dam will have an under-
ground powerhouse,intake structure,outlet works,
and main spillway.A 38-foot (11.7-m)diameter
tailrace tunnel will convey the turbine discharge
approximately 1.3 miles (2.2 km)downstream from the
arch dam.
During construction of the dam,the river will be
blocked above and below the construction site by
cofferdams.The flow will be diverted into a
35.5-foot (10.8 m)diameter horseshoe tunnel,1,490
feet (451 m)long,and discharged back into the river
channel.The upstream and downstream cofferdams will
be about 400 feet (120 m)long and 200 to.400 feet
(60 to 120 m)wide.
The adverse impacts upon aquatic habitat at the Devil
Canyon damsite are expected to be similar to those at
the Watana site but of lesser magnitude.
At the Devil Canyon damsite,the Susitna River is
confined to a canyon approximately 600 feet (180 m)
deep and 200 to 400 feet (60 to 120 m)wide at river
level.The river bottom is primarily composed of
cobbles,boulders,and blocks of rock;the water is
extremely turbulent.Few fish live in the area of
the damsite (ADF&G 1981f).Some chinook salmon
migrate upstream past the Devil Canyon damsite(ADF&G
1983a,1984h,1985b)
-Alteration of Waterbodies (*)
Impacts from Devil Canyon Dam construction will be
primarily restricted to the vicinity of the
damsite.A 1,100-foot (333-m)section of the
Susitna River between the cofferdams will be
dewatered for 7 years during construction.
Although a small population of Dolly Varden,
E-3-2-18l
sculpin,and other resident species inhabit that
stretch of river,it is not expected that
dewatering will have more than a minor impact upon
availability of suitable aquatic habitat.The dam
foundation will cover about 90 feet (27 m)of river
bottom.This is considered to be a minor impact.
During construe tion,wa ter velocities with in the
diversion tunnels will be sufficintly high to
prevent the upstream migration of chinook salmon.
The Devil Canyon Dam will be a permanent,total
migration barrier upon its completion.
The greatest impacts during construction of the dam
are likely to be associated with gravel mining and
processing in Borrow Site G.Gravel for filter
material and for concrete aggregate will be removed
from the Susitna River and from Cheechako Creek
alluvial areas upstream from the damsite (Borrow
Site G).The effects of gravel mining on aquatic
systems have been discussed under Section 2.3.l.a.
Since themateI'ialremoval.sites will be inundated,
impacts at the sites will be transitory.
-Changes in Water Quality (0)
Potential impacts to water quality would primarily
be caused by increases of turbidity due to erosion
.a.nd ..throughcdisc harge-o,Leffluen tfrom the .
concrete batching process.To minimize water
quality impacts,all processing waters will be
treated before being discharged to the S~sitna
River.Turbidity increases in the Susitna River
are expected to be:negligible.See Section 2.3.1.a
for discussion.
-Disturbance of Fish Populations (0)
I
851021
-·--rnstreamac t-ivi-t:ies-durifig ml:fteri"c~ftejrtra-c-ti-orftfe-a:r
Cheechako Creek could disrupt fish movements,
spawning,and rearing in the creek,depending
upon location,type and duration of activities.It
is unlikely that the damsite itself is located in a
stretch of the Susitna regularly inhabited by fish;
therefore;the excavation and blasting required at
the damsite would.not be disruptive to fish
····_poputa:t-ioni;".
E-3-2-l82
1
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851021
(ii)Construction and Operation of Devil Canyon Camp and
Village (*)
During construction of Devil Canyon Dam,housing will
be constructed for approximately 1,900 persons
(Exhibit A,Section 6.13).The construction camp and
construction village will be located between 1.7 and
3.4 miles (2.8 and 5.6 Ion)southwest of the damsite.
The camp will include bachelor dormitories,
cafe teria,warehouses,0 ffices,hospital,and
recreational buildings.The village will contain
housing for 160 families and will include a school,
stores,and a recreation area.
The camp will be approximately 0.5 mile (0.8 Ion)from
the village.Both developments will be more than 700
feet (210 m)above the Susitna River and more than
4000 feet (1,200 m)from the edge of the canyon.
Water,sewage,and solid waste disposal facilities
will be shared by both developments.Water will be
withdrawn from the Susitna River and effluent from a
secondary treatment system discharged into the river
below the water intake.The upper reaches of Jack
Long Creek border the camp and the village to the
south,coming to within 200 feet (60 m)of the camp.
A small unnamed creek drains a series of lakes 3,000
feet (900 m)to the east of the camp and enters the
Susitna at RM 150.The creek is paralleled by the
sewage outfall line for 1,000 feet (300 m)or about
20 percent of its length.
Both the camps and the village are temporary develop-
ments to be removed when Devil Canyon construction is
completed.Permanent personnel responsible for
operations of the Devil Canyon dam will live at the
Watana permanent town.No airstrip will be built;
air access will be via the permanent runway at
Watana.
The unnamed creek and lakes may support grayling,
Dolly Varden,or sculpin,while Jack Long Creek
contains pink,chinook,chum,and coho salmon.
Portage Creek contains chum,pink,chinook,and coho
salmon,rainbow trout,round whitefish,and humpback
whitefish.Chinook salmon,grayling,and Dolly
Varden are found in the lower reaches of Cheechako
Creek (ADF&G 1983a,1983b,1984a,1984b,1985a).
Temporary impacts resulting from camp/village
operations are expected to be limited to the area
within a few miles of the damsite.
E-3-2-183
851021
Alteration of Waterbodies (*)
No water bodies are expected to be altered as a
result of Devil Canyon camp construction other than
those resulting from gravel mining within the
Susitna River floodplain at Borrow Site G.Since
this borrow site will eventually be inundated,no
permanent effects from gravel mining will occur.
Camp construction is not anticipated to affect Jack
Long Creek or the unnamed stream.
-Changes in Water Quality (*)
Erosio~into the Susitna River from 'gravel mining
at the mouth of Cheechako Creek is not expected to
resul t in ad ver se impacts to fish.Because 0 f
its proximity to the developments,Jack Long Creek
could receive uncontrolled runoff from the camp
area;however,required drainage facilities and
retention ponds should prevent this impac t and no
increase in sediment levels in Jack Long Creek are
expected ..
Water for camp use will be withdrawn from the
Sus itna River,and treated effluent will be
returned to the river.The treated effluent will
not affect the waste assimilative capacity of the
Susitna and is expected to have no significant
effect on the·aqua·t-iG envcironment {Exhibit ..E,.
Chapter 2,Section 4.2.l(g)(i)).Storm drainage
and oily water runoff from the construction camp
~itl be collectecf and treated as noted above.
The fuel storage area fs loca.ted on the south side
of the construction camp about 200 feet (60 m)
above Jack Longereek.A.ccidental fuel spills are
notexpec ted to l:"each the creek since st()rage
fac iIi tIes ··wi:I.Tbe desIgneir--to-conta 1.n moi:ethan
...-the maximums toraoTevol ume ~---rt-is-not-expec tecr-
that runoff from the solid waste disposal site and
the construction village will adversely affect any
waterbodies since both will be collected and
treated the same as the runoff from the camp area •
...Direct Construction Activity (*)
-Tne camp -a.nd CviTlage-a-t the-Devil Canyons i te will
hous e ap prox imate ly 1,900 wor ker s fo r sever al year s
(EXhibit A,Section 6.13).As a result,streams
E-3-2-184
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and lakes in the vicinity may be subjected to
increased fishing pressure.This area has -not been
heavily utilized for sport fishing in the past.
The waterbodies most likefy to be affected include
Cheechako Creek,unnamed creeks and lakes in the
vicinity,Jack Long Creek,and to a lesser extent,
the Susitna River and Portage Creek.With the
exception of Portage Creek,these waterbodies are
within walking distance of the camp/village and the
damsite.Portage Creek enters the Susitna River
from the north about 2.5 miles (4.1 km)downstream
from the dam location.
(b)Filling Devil Canyon Reservoir (*)
Filling Devil Canyon reservoir would inundate approximately
32 miles (52 Ian)of Susitna River mainstem habitat and 6.2
miles (10 Ian)of tributary habitats.These habitats would
be converted from lotic to lenti&systems with accompanying
changes in hydraulic~characteristics,substrate,turbidity,
suspende&·sediment concentrations,temperature,and nutrient
levels (Exhibit E,Chapter 2,Section 4.2.2).
The filling of the Devil Canyon reservoir will be done in
two stages.Upon completion of the dam toa height
sufficient to allow ponding above the low level outlet
facilities,the water level will be raised to an elevation
above 1,050 feet (315 m)but not exceeding.1,l35 feet.(343
m).This filling will be accomplished in approximately 4
weeks.As soon as the power facilities and main spillway
are completed (approximately two years),the reservoir will
be raised to 1,455 feet (440 m),the normal operation
elevation as explained in Exhibit E,Chapter 2,Section
4.2.2.(b).During filling of Devil Canyon,discharge from
the project will be maintained within the Case E-VI flow
constraints defined in Table E.3.2.59.
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851021
(i)Effects in Impoundment Area (*)
Closure of the Devil Canyon Dam and filling of the
reservoir will result in the inundation of
approximately 32 miles of the Susitna River and a
total of approximately six miles of the lower reaches
of the five named tributaries (Figure E.3.2.85).
The lower reaches of several unnamed tributaries will
also be inundated,but the lengths of these
tributaries have not been determined.The only
presently existing lake to be affected by the Project
will be a shallow,five-acre pond at the damsite,
E-3-2-185
851021
which wi 11 be fi 11ed by the saddle dam associated
with the main,concrete arch Devil Canyon Dam.The
reach of the Susitna River within the Devil Canyon
Reservoir presently supports small populations of
Arctic grayling,burbot,longnose sucker,whitefish
and Dolly Varden (ADF&G 1981f,1983b).In addition,
a small population (25-75)of chinook salmon spawn in
tributaries within the impoundment zone.Impacts on
mainstem,tributary and lake habitats will be similar
to those described for Stage I Watana Reservoir.Due
to the short period of time necessary to fi 11 Devil
Canyon Reservoir,the effects of the reservoir are
more appropriately and completely described in
Section 2.3.2.c.i.
(ii)Devil Canyon to Talkeenta Reach (***)
Effects of Altered Flow Regime (***)
During the filling of Devil Canyon Reservoir,
discharge from the dam to the middle Susitna
River will'be maintained within the Case E-VI flow
constraints.The effects of the altered
flow regime during filling are discussed as part of
the initial Stage II operation.The effects on
middle river aquatic habitats,therefore,are
discusse,d in Section 2.3.2.c.ii.During the period
the water level is being held constant at el.1,135
--~,the--effec'ts~wiH~be--the'-same-~as··fot"-Watana ··S tage I
oper ad on (di scus sed in Sec tion 2.3.1)since
discharge wi 11 be regulated only at Watana.
-Effects of Altered Temperature/Ice Regimes-(***)
As with the discussion of the effects of the
altered flow regime during filling of Devil
C.a:g,Y_9nR~§l~~YQi~L~ijl3c:uSf:).!o_l1o_Ll:h~....~.~Jec ts f the ...............
anticipated altered temperature and ice regimes
--during filling of'-the--n,evil'.Canyon Reser"vo-fr-are --------------------.---..
more appropriately discussed under Stage II
operation effects.Changes in temperature regimes
during filling will occur for 4-6 weeks in October
and November of the year 2004 and,hence,any
changes associated only with Devil Canyon filling
win-becif 'a short duration and'will occur at a
time when fish utilization of mainstem and mainstem
"-S;ssocfiEedna.bifiEs istloE likely to be extensively
affected.Also,since filling of Devil Canyon
Reservoir will occur prior to the onset of winter
conditions,filling of Devil Canyon will not affect
E-3-2-186
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851021
ice processes ~n the river.Ice processes,
however,will be affected by operation of Stage II
as discussed in Section 2.3.2(c)(ii).During the
period when the water level is being held constant
at el.1,135,the river temperature and Ice
conditions are expected to be similar to those
discussed for Watana Stage I in Section 2.3.1,
since the storage volume in Devil Canyon will be
very small (see Section 4.2.2(d)).
-Effects of Altered Sediment Regime (**)
Effects of filling will be relatively short lived
in relation to the projects life time and most
effects are more appropriately discussed under the
topic of Stage II Operations (Section 2.3.2.c.ii).
In general,downstream water discharges during
Devil Canyon filling will have a higher 1'8S and
turbidity loads than that expected during Stage I
operations.The al tered sediment regime associa.ted
with filling Devil Canyon Reservoir will be
detectable within the middle river reach,but the
lev~ls of TSS and turbidity will likely be less
than or well within the ranges of values.,for these
same parameters which have been observed under
natural conditions.Effects at the aquatic
biological community level are expected tro be
minimal.During the period when the water level is
being held cons tantat el.1,135,the suspended
sediment and turbidity are expected to be similar
to Watana Stage I operation,as discussed in
Sec tion 2.3.1.
-Effects of Other Water Quality Changes (**)
Effects of any additional water quality changes
resulting from filling will be relatively short
lived in relation to the project's life time,and
are more appropriately discussed under the topic of
Stage II Operations (Section 2.3.2.c.ii).
Dissolved and particulate organic materials of
allochthonous origin are expected to increase in
concentration during the short filling period,but
the long term effects associated with these
increased organics are expected to be minimal at
the level of the aquatic biological community.
E-3-2-187
851021
(iii)Talkeetna to Cook Inlet (***)
-Effects of Altered Flow Regime (***)
As discussed in Section 2.302.b .ii,discharge from
the Devil Canyon Dam during filling of the
reservoir will be maintained within the Case E-VI
flow constraints and will be similar to operation
of the project given the energy demands at the time
filling occurs.Therefore,the effects of the
al tered flow regime during fill ing of Devil Canyon
Reservoir on habitat in the lower river are more
appropriately discussed tmder project operation
(Section 2.3.2.c.iii).During the periods the
water level is being held constant at el.1,135,
the effects on streamflow would be similar to Stage
I Watana oper~tion discussed in Section 2.3.1.
-Effects of Altered Temperature/Ice Regimes (***)
As with the discussion of the ..impac ts of the
altered flow regime during fill ing of Devi 1
Canyon Reservoir on aquatic habitats in the lower
river,the effects of altered temperature and ice
regimes are more appropriately discussed in Sec tion
2.3.2.c.iii.During the period the water level is
being held constant at el.1,135~the effect on
temperature and ice would be similar to Stage I
.~-Watana~operation~cdiscussed..in-Section..2.3.L.
-Effects of Altered Suspended Sediment Regime (***)
Effects'of filling will be short lived and are more
appropriately discussed tmder the topic of Stage II
Operations (Section 2.3.2oc.ii).During the
period the water level is being held constant at
el.1,135 the effects·on suspended sediment wouldbesImilarto·SEage·::CWatana·op(ira tionci i s Cuss·ed iil.-
In general,open water season levels of suspended
sediment and turbidity may be higher t9an those
expected during Stage I or Stage II Operations.
However,during the open water season,the
influence of Stage II filling on the suspended
se<iime!1tl::~gim.ejnt:heJ9werriveris expected to
be negligableduetodilution by other tributaries
with high and naturally variable sediment regimes.
Effects at the aquatic biological community level
are expected to be negligible.
E-3-2-188
851021
-Effects of Changes in Other Water Quality
Factors (**)
Effects of any additional water quality changes
resulting from Stage II filling are expected to
be both.short lived,with respect to the project's
lifetime,and relatively negligible with regard to
the aquatic biological community.
Dissolved and particulate organic materials of
allochthonous origin are expected to increase
substantially in concentration during the short
filling period,both within and downstream of the
reservoir.Long term effects to the aquatic
biological community due to these increases in
dissolved and particulate organic materials are
expected to be negligible.
(iv)Estuary at Cook Inlet (***)
Effects of filling on the estuary are expected to be
temporary and are more appropriately discussed under
project operation (Section 2.3.2.c.iv).
(c)Effects of Operation of Stage II Watana/Devil Canyon
Dam (**)
As stated previously,the Devil Canyon Reservoir will
inundate approximately 35 miles of mainstem habitat and
approximately 6 miles of the lower reaches of·five named
tributaries.
The Devil Canyon Reservoir water surface elevation will
remain stable at near maximum operating levels most of the
time.No drawdown of the Devil Canyon Reservoir is
anticipated during wet years.A drawdown of approximately
20 feet may occur in median flow years during July,with
refilling occurring in August (Figure E.3.2.86).A drawdown
of approximately 50 ft is anticipated for dry years.During
Stage II operation,Watana Reservoir will be drawn down in a
manner similar to that described for Stage I operation.The
expected drawdown cycle for Watana Reservoir during the
operation of Stage II is depicted in Figure E.3.2.87.The
lengths of tributaries to the Devil Canyon Reservoir within
the drawdown zone are provided in Table E.3.2.90.
Suspended sediments transported to the Devil Canyon
Reservoir generally consist of particles less than 5 to 10
microns in diameter (Exhibit E,Chapter 2,Section
4.2.3(c)(iii».Larger particles will be trapped in the
E-3-2-189
851021
Watana Reservoir.Sediments will also be introduced into
the flow from the tributaries dtiringfloods and erosion 0 f
reservoir shorelines.Some of the particles will settle in
the Devil Canyon Reservoir,but the majority will pass
through,contributing to turbid.ity in the reservoir and in
waters released downstream.Small deltas will likely form
at the mouths of the tributaries.However,these are not
expected to significantly alter fish habitats.
Temperature regimes in Devil Canyon Reservoir will be highly
dependent upon the temperature of the water released from
Wat~na Reservoir.The Devil Canyon Reservoir will stratify
during June and July each year as warmer water from Watana
enters the reservoir and remains at the surface.Maximum
outflow temperatures will range between 8 and 10°C (Exhibit
E,Chapter 2,Section 4.2.3(c)(i»).In July and August in
most years,the outlet works in Devil Canyon Dam will be
operated to release water in excess of .that required for
generation.This excess water will result because the
Watana and Devil Canyon Reservoirs will have reached full
storage capacity.Once the outlet works are operating,the
cold,turbid,deeperwater(4~C)wilLbe evacuated from the
reservoir and replaced by warmer Watana water (Exhibit E,
Chapter 2,Section 4.2.3(c)(i)).In some years the
reservoir will become uniformly mixed at about 8-10°C by
mid-August and will remain relatively warm through
September.The reservoir will then cool unt{l it becomes·
isothermal at 4'!C in October.After that time,the·surface
___~at~t"~~il..L~QQ.LJ::oOoGan(L~!Lice~Qver~ttLfotill_.II1
general,the seasonal temperature regime in.Devil Canyon
Reservoir wi 11 closely follow that of Watana.
(i)Effects of Operating Devil Canyon Reservoir (**)
Effects on Mainstem Habitats (**)
The mainstem habitats within the Devil Canyon
Reservoir presently .supp<:rrt ...small-po-pul-ationso·f··
--burbo·t-and-louglios·e····-su·cker·s-throughout-·the--year.--
Arctic grayling,Whitefish and Dolly Varden
populations use the mainstem for overwintering
(ADF&G 1981f,1983b).
The stable water level in Devil Canyon for most of
the year wilLhelpcreate.more.favorable spawning
conditions for most fish species.Arctic grayling,
lake trout,·burbot,whitefish and·"longiiose sucker
spawning is expected to be unaffected by the
drawdowncycle.Dolly Varden eggs that are
deposited in the draw down zone of reservoir
E"-3-2-190
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851021
tributaries during September and October may
experience a higher mortality than those ,deposited
above the draw down zone.The impact to Dolly
Varden populations in the reservoir is expected to
be minor.
Productivity in the 'Devil Canyon reservoir is ex-
pected to be low because of the turbidity levels--
the expected turbidity in Devil Canyon is described
in Exhibit E,Chapter 2,Section 4.2.3(c)(iii)--but
should be greater than the productivity in the
Watana reservoir because of the less extreme
draw-down cycle.It is expected that the Devil
Canyon reservoir will develop limited resident
populations of Dolly Varden,burbot,whitefish and
other species.Arctic grayling will occur in and
at the mouths of clear-water tributaries.
-Effects on Tributary Habitats (**)
As with the.tributaries that flow into the Watana
impoundment,the lengths of the tributaries to be
affected by the Devil Canyon impoundment will
vary according to their gradients and location
within the impoundment.The locations of the
tributaries,the stream gradients and lengths of
affected reaches are summarized in Table E.3.2.91.
Effects on tributaries and associated fish are also
expected to be similar to those presented for the
Watana Reservoir.Most of the tributaries in the
Devil Canyon impoundment area are characterized by
steep slopes with occasional barriers,such as
waterfalls.Cheechako,Devil and Tsusena Creeks,
three tributaries entering the Devil Canyon
impoundment,all contain waterfalls.These falls
will not be inundated by the impoundment and would
still function as barriers to fish passage.
Species presently using tributary habitats include
Dolly Varden,Arctic grayling and whitefish.
The loss of clear-water tributary habitat in
Tsusena and Fog Creeks will eliminate habitat
utilized by approximately 1200 grayling longer than
8 inches (20 cm)(Table E.3.2.24).However,
because the water surface elevation in Devil Canyon
Reservoir will remain relatively constant during
the Arctic grayling spawning and incubation period,
the effects of reservoir filling and operation on
E-3-2-191
Arctic grayling are expected to be less severe than
those anticipated in the Watana Reservoi~.
As discussed in Section 2.3.l.c.ii,a small
population (25-75)of chinook salmon presently use
habitats near the mouths of four tributaries for
spawning.This utilization is expected to increase
to some extent during the period between initial
operation of Stage I and closure of the Devil
Canyon Dam.Diversion of the Susitna River for
construction of the Devil Canyon Dam will eliminate
salmon population use of the areas within the Devil
Canyon Impoun:dmentZone.
(ii)Devil Canyon to Talkeetna (**)
Effecfsof Altered Flow Regime (**)
operation of Stage II will begin after completion
of the Devi I Canyon Dam and filling of the
reservoir.The completion of the Devil Canyon Dam
is scheduled for the year 2005 with initial
operation beginning in late 20050 Discharge from
the Devil Canyon Dam will be influenced by the
discharge from Watana Dam.The annual discharge
regime and changes to the discharge regime between
Stage I and Stage IF are,therefore,limited by "the
storage capacity in the Stage I -Watana
Reser_v:oir.
During the Stage II operation period,the system
demand for energy is expec ted to grow from
approximately 4,800 GWH annually to approximately
5,500GWH annually.Growth with corresponding
average annual energy production from the Stage II
project is expected to be from approximately 4,200
GWH annually to 4,560 GWH annually.To repre sent
-----------------------tne-StageTt -fl-ow-ri'fgime-;---dis"charg es a t-"Gold"Creek
'''-'----a.-s-so-c"i-a."tea-whh~s:Y"s.t-eln-en-e-rgy-dema.nd-o-f---"---,---~--
approximately 5,270 GWH and an average annual
energy production of approximately 4,440 GWH were
used for the habitat analysis.Average weekly
discharges at Gold Creek for the 34 years of record
to meet this energy demands and average energy
production are presented in Exhibit E,Chapter 2
Section4.2.3~a~'MaxiIIJ.um,minimum and mean monthly
average-di-scharges~~a1:G()];-d-Creek associated with
this production are summarized in Table E.3.2.9l
along with the same values for natural conditions.
Comparison of the mean monthly average flows at
1
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851021 E-3-2-l92
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851021
Gold Creek during Stage I operation (Table
E.3.2.73)with those during Stage II operation
(Table E.3.2.91)indicates that little difference
in the discharge regime is expected between the two
stages •
•Effects on Principal Evaluation Species/Habitat
Combinations (**)
Chinook Rearing Habitats (**)
Chinook rearing habitat areas associated with
Stage II operation flows were analyzed in the
manner described for the Stage I flow regimes.
Total chinook rearing habitat areas were derived
for the average weekly flows under Stage II
project operation and from the total chinook
rearing habitat area response curve presented in
Figure E.3.2.64 and Table E.3.2.46.
Probabilities of exceedance values were
calculated for the 90,50,and 10 percent
exceedance levels and are presented in Table
E.3.2.93 and in Figure E.3.2.88.Also
presented are the habitat values for the natural
flow regime.Comparisons of these values with
the probability of exceedance values for Stage I
(Figure E.3.2.75),which indicate that little
change in the rearing habitat area associated
with the Stage II discharge regime is expected.
Total chinook rearing habitat areas during the
early summer weeks under the Stage II flow
regime are expected to be slightly less than
under the natural flow regime (Table E.3.2.43).
By mid-summer (after Calendar Week 27),the
ranges of habitat areas available in each week
will be nearly the same as under the natural
flow regime as depicted in Figure E.3.2.88.
Under natural conditions,juvenile chinook
become prevalent in mainstem affected areas
after the early part of July,beginning in
Calendar Week 26,(See Figure E.3.2.37).The
apparent reduction in total suitable habitat
area available in June under the Stage II flows
occurs when few chinook juveniles are expected
to be present in the mainstem affected areas
and,the apparent loss of available habitat is
not expected to affect the juvenile populations.
As observed for the Stage I flows,variation in
the amount of habitat available from week to
E-3-2-193
--_.--.---_.-
851021
week and year to year would be less during Stage
II operation than under the natural flow
regime.
The median chinook rearing habitat in
Representative Groups 2,3,and 4,however,is
expected to be greater under the Stage II
operational flow regime than under the natural
regime.Median (50 percent),90 and 10 percent
exceedance values of habitat area in the three
groups under Stage II flow conditions are
presented in Table E.3.2.93,together with the
habitat areas estimated for the natural flow
regime.These are depicted graphically in
Figure E.3.2.89.The range of available habitat
areas is somewhat less during the early part of
the summer,corresponding to the filling period
for Watana Reservoir.Later in the summer,once
the Watana Reservoir is filled,the median and
range of habitat area is nearly the same as
under natural conditions._
During the winter months,the probability that
juvenile chinook survive through the winter is
expected to increase from the Stage I flow
regime.Al-though discharges during the winter
months in Stage II will be simelar to those in
Stage I,the ice front is not expected to
--""'-~~progress-as--farupset-ream (s eed-i-scuss-ion-o f
Effects of Altered Temperature/Ice Regime
presented below).Thus,some additional habitat
sites which.may be used by juvenile chinook for
overwintering wilJ not be subjected to
overtopping due to staging of the water surface.
Hence,juveniles inhabiting the sites will not
be subjected to O°C,high velocity water.Also,
.....!J~~g!_Ilg~1.l__~h~J~_~=£gy~:re d ....._:r.~c:l Cl:l_..!S .~:lCJ)E!C~E!<i ..._..~()._
be less than during Stage I operation with the
---.-----result that srEes In the -lce covered reach wiTt-----
not be as likely to overtop or if they do
overtop,the volume of water diverted through
the site will be less.A more complete
discussion of the ice processes during Stage II
is presented in Exhibit E,Chapter 2,Section
4~2~3~.The effects of ice processes on juvenile
chinook are_discussed in more detail in Section
2.3.Le.ir~Effeets6fAlteredTemperature/Ice
Regime.
E-3-2-194
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851021
Chum Spawning Habitats (**)
Additional changes from those expected during
Stage I operation in factors affecting chum
spawning habitats are not expected to occur as a
result of the transition from Stage I to Stage
II operating flow regimes.As discussed
previously,little change in the discharge
regime is expected in the transition from Stage
I to Stage II (Table E.3.2.91).Hence,
conditions for chum access into spawning
habitats will be similar to that described for
Stage I.A summary of access conditions at
passage reaches affected by mainstem discharge
during Stage II operation is presented in Table
E.3.2.94.Access conditions at natural
discharges during August and September are also
presented in the table for comparison.
Total chum spawning habitat areas for average
weekly discharges in August and September were
calculated using the 34 years of average weekly
discharges anticipated under Stage II operation.
Translation to total spawning habitat areas were
based on the habitat area response curve for the
modeled chum spawning si tes presented in Table"
E.3.2.47 and Figure E.3.2.59.Probable habitat
areas exceeded 90,50 and 10 percent of the time
were calculated for each week in August and
September.These values are presented for the
Stage II flow regime in Table E.3.2.95 and are
depicted graphically in Figures E.3.2.90.
Comparison of these habitat areas with those
presented for total chum spawning habitat areas
during Stage I (Figure E.3.2.77)demonstrates
that the total habitat areas available during
the spawning period in those sites traditionally
used by chum under the natural flow regime will
be somewhat less during Stage II than during
Stage I operation.The available spawning
habitat will be nearly the same as that observed
under natural flow conditions (presented in
Table E.3.2.95).In addition,the week to week
and year to year variation in chum spawning
habitat during Stage II will be nearly identical
to that observed for the natural flow regime.
This is due to the fact that the Watana
Reservoir is expected to be refilled by the
first part of August each year with subsequent
E-3-2-195
average weekly discharges approaching natural
flows.
Analysis of the chum spawning habitat
availability in Representative Groups 2,3 and 4
during Stage II operation yields similar
results.Spawning habitat areas derived using
the aggregate Representative Group habitat
response curve presented in Table E.3.2.48 and
Figure E.3.2.63 are presented in Table
E.3.2.96 arid are depicted in Figure E.3.2.91.
The median habitat areas expected to be
available in Representative Groups 2,3 and 4
during Stage II operation are nearly the same as
those expected during Stage I operation.As
wi th the previous'analysis'of chum spawning
habitat in modeled sites,the week to week and
year to year variation in the availability of
spawning habitat will be greater during Stage II
than during Stage I operation and will approach
that variation observed under the natural flow
regime.
Survival of chum salmon embryos during the
incubation period is expected to be similar to
that expected under Stage I.'!his is i.ndicated
by the habitat area values for suitable spawning
habitat in the modeled chum spawning sites
during.t.he .•Q(:t.ob"e,"t'.andNo..Y_emh"er.p.e,"t'i.Qd,p"t'es.ented
in Table E.3 ..Z.97 in comparison with the values
fo r Stage I operation presented in Table
E.3.2.79.Habitata:reas in the modeled sites
for the natural flow regime are'also presented
in Table E.3;;2.97 "for comparison.Habitat areas
for the Stage II flow regime,presented in Table
E.3.2.97,are depicted graphically in Figure
E.3.2.92.During Stage II operation,.
'-e-ssent:ially"n<f"vafi"at'ion is'evident ..in'thechUfil
......,,---''.---".,,,.---,----.,,.--------'s'p'awn-ing-h'a'bitat-a-re'a-avai-l"a'b,te'-fo'r-inc'ub'arion'
of the embryos during October and November.
This is due principally to the ability of the
Stage II operation to consistently meet the
energy needs of the system.
;(
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851021
Similar.results are obtained using the habitat
area response curve for chum spawning habitat
"'area.~·in:Representa.1::FveGroups 2,3 and 4 (Table
E.3.2.48).The 90,50 and 10 percent equalled
or exceeded habitat areas included in the three
representative groups for the Stage II flow
E-3-2-196
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851021
regime are presented in Table E.3.2.98 and are
depicted graphically in Figure E.3.2.93.
Some increase in the survival of chum embryos in
some sites is expected as a result of changes in
the ice processes associated with Stage II
operation compared with Stage I operation
(Exhibit E,Chapter 2 Section 4.2.3).Since the
ice cover is not expected to extend as far
upstream during Stage II as expected during
Stage I,some spawning areas that were subject
to overtopping as a result of staging,will be
less likely to overtop under Stage II.Also,
sites located in the reach expected to become
ice covered will be less likely to over top
because staging is expected to be less than
during Stage I •
•Effects on Other Evaluation Species/Habitat
Combinations (***)
Because the discharge regime during Stage II is
expected to be nearly the same as that
described for Stage I,no additional effec ts due
to altered flow regime to other evaluation
species/habitat combinations are expected.
Hence,the changes to habitats described for
Stage I will be maintained through Stage II.The
prolongation of habitat conditions associated
with Stage I is expected to benefit the various
species/habitat combinations by providing long
term habitat stability.
-Effects of Altered Temperature/Ice Regimes (***)
Differences between water temperatures under
natural conditions and under project operation
conditions are more pronounced during Stage II
operation than under Stage I operation at all
locations within the middle Susitna River.These
differences are depicted in Figures
E.3.2.94,E.3.2.95 and E.3.2.96 for RM ISO,130 and
100,respectively.
The regimes depicted in these figures represent the
expected temperatures assuming discharges expected
During Stage II operation.The estimated
temperatures also assume climate and flow
conditions recorded during 1981 and 1982.The
expected temperatures at other locations in the
E-3-2-197
middle river through the summer using the same
climate,flow and demand assumptions are .presented
in Tables E.3.2.99 and E.3.2.l00 for 1981 and 1982
respectively.Because river temperatures expected
under Stage I operations are nearly the same as
natural conditions,the temperature changes induced
by Stage II operation represent the major project
induced changes in summer temperatures which could
affect the utilization of aquatic habitats by
various fish species.At RM 150,near the mouth of
Portage Creek,summer.water temperatures are
expected to be 2°to 6°cooler than under natural
or ,Stage I operating conditions from May through
July.In August,with-project temperatures are
similar to natural.From September through mid-
November,water temperatures will decline but at a
much slower rate than under natural qr Stage I
conditions.Thus,temperatures are expected to be
2°~6°C warmer.During the period November through
March,water temperatures are expected to be
between 1°and 2°C with no ice forming in the upper
end of the middle.river.
AtRM 130,cool water temperatures are maintained
from May through July •Differences between natural
and Stage II operation range from 2-4°C cooler.
After October,water temperatures are 2°to 4°
warmer.Through the winter,water temperatures are
expected to be less than 1°C mos t of the time withoccasToiiaIperlodsof=-O~oc water in~the mafnstem:
During Stage II operation,an ice cover may
occasionally format RM 130 as depicted in the ice
simulation presented in Figure E.3.2.97.
At RM 100,near the confluence of the Chulitna
River with the Susitna River,water temperatures
are expected to be 2-3°c cooler during Stage II
...~-----~------·---------than--naturaI-tempera tures--fo rthe .May-July-o-After
-__..~--m-id""'Sep.tember-,-,-wa-ter-temp e-rca-turce.-i-s-ex-pected-to-be~---..
2-5°C warmer until mid-to late November (See
Figure E.3.2.96).Ice.cover is expected to form in
the lower portions of the .middle river in late
December and will remain in the area until late
March,at which time the ice cover will melt out
(SeeFigure~.3.2.9Z).From the end of March until
the beginning of May"water temperatures are likely
tobel~2~C'tYarlIler.~~than_undernatural conditions.
As with the other locations in the middle reach and
as under Stage I conditions,the seasonal
temperature pattern is expected to be shifted about
1r
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851021 E-3-2-198
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851021
one month later in the season than under natural
conditions.This is due principally to the large
time required for Watana reservoir to gain and lose
heat relative to the natural stream,which is
shallower and better mixed than the large
reservoir •
•Effects on Principal Evaluation Species/Habitat
Combinations (***)
Juvenile Chinook Rearing Habitats (***)
During operation of Stage II of the Susitna
Hydroelectric Project,water temperatures
during May to July are expected to be 2-6°C
cooler than under natural conditions.These
cooler temperatures could affect j.uvenile
chinook rearing by retarding the growth rates of
those fish occupying mainstem associated
habitats such as side channels.However,based
upon size data collected in tributary habitats,
juvenile chinook which remain in the tributaries
generally grow to somewhat larger sizes than
those occupying side channel and mainstem
habitats (See Table E.3.2.10).Water
temperatures in tributary habitats are generally
2-4°C cooler than mainstem temperatures between
May and July,similar or slightly cooler than
mainstem temperatures in August,and slightly
warmer than mainstem tempertures in September
and October (Exhibit E,Chapter 2,Section
2.3.l{c).Brett (1952)suggested that although
most rapid growth 0 f juvenile sockeye fed to
satiation occurs at approximately 15°C,juvenile
growth efficiency (i.e.conversion of food
biomass to fish biomass)is probably greater at
some lower temperature.The observed difference
in growth between juveniles in tributary and
juveniles in mainstem habitats could be
accounted for through higher growth efficiency
or more food available.Water temperatures in
side channel rearing habitats are expected to be
more similar to tributary water temperatures
and,therefore,juvenile chinook incremental
growth could approach that observed for
juveniles in the tributaries.Specific growth
rate for a population is highly dependant upon
ration (food available),the temperature regime
to which they are exposed and inherent
physiological adaptations.Hence,statements
E-3-2-199
851021
regarding the effects·of temperature on juvenile
chinook cannot be conclusive.Based on
temperature tolerance curves developed by AEIDC
(l984b),water temperatures are expected to be
within tolerance ranges through the summer
(Figure E.3.2.98).
During winter months,juvenile chinook generally
move into side slough habitats to overwinter.
In the upper reaches of the middle Susitna
mainstem and side channel habitats will remain
at I-3°C throughout the winter,similar to water
temperatures in unbreached side sloughs under
natural conditions.Therefore,the warmer water
released from the Devil Canyon Dam is expected
to increase the total habitat area with water
temperatures in a.more amenable range for
survival through the winter months.Downstream
from the action of the ice front,side slough
ha.bitats will be the only areas likely retaining
water temperatures greater than O°C.However,
···becauseo,fthe staging associated with ice cover
formation,many of the sloughs may be breached
as depicted in Table E.3.2.101.Survival of
juvenile chinook could be reduced in side
sloughs which are breached and convey O°C
mainstem water.
Outmigration~o.£j.u~eniLe_chinook.from
tributaries intomainstem areas and ultimately
out of the middle river would not be to
significantly impacted by the cooler
temperature.Some delay in outmigration from
the middle river due to the lower mainstem
temperature may occur (AEIDC 1984a).However,
the delay is not expected to be sufficient to
lead to excessive mortality of juvenile chinook
Tn Elie'lower-ii"ver·or Til"Ene riia rine·
Effects on Chum Spawning/Incubation
Habitats (***)
Upstream migration of adult chum salmon into the
middle·,river·gener·ally occurs be tween late
JlilyartdlateAliglist.During this period,water
'temperatures "are-generally expected to be within
the natural range of temperatures.During the
early part of the migration season,however,
somewhat cooler temperature may re tard the rate
E-3-2-200
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851021
of upstream migration to some extent.Because
chum salmon tend to remain in mainstem areas for
sometime prior to moving into spawning habitats,
this retardation is not expected to adversely
affect spawning activity.Once chum salmon move
into side slough habitats to spawn (i.e.
Representative Groups 2 and 3),water
temperatures are expected to be similar to
temperatures encountered prior to construction
and operation of the reservoirs.It is likely
that a key factor in chum salmon selection of
spawning sites is the temperature difference
between the surface water temperature and the
temperature of the water in upwelling areas.
Since groundwater upwelling temperatures average
from 2°C to 4°C,temperature differences will
still be detectable and,therefore,spawning
activities are not expected to be adversely
af fec ted.
Incubation of chum embryos in side sloughs is
not expected .to be adversely affec ted by
mainstem temperatures unless the spawning area
is breached as a result of staging associated
with the ice cover.Breaching of spawning areas
due to ice cover formation is expected at most
sites downstream from the location of the"ice
front.The maximum upstream location of the ice
front is at approximately RM 133 in an average
winter and may be a few miles downstream or
upstream in a warm or cold winter,
respec tively.
Breaching of a site between RM 100 and RM130,
if it occurs,will occur beginning in late
December and subside in mid-March at the lower
reaches in an average winter.The duration of
overtopping may be a few weeks more or less in a
warm or cold winter,respectively.Further
upstream,the breaching will occur somewhat
later and will subside somewhat earlier as de-
pictedin Figure E.3.2.96 and Table E.3.2.l01.
In the upper reach affected by ice cover forma-
tion,a particular site may be breached two or
more times in a single winter,e.g.Slough 8A,
located at RM 126.0,may be overtopped twice
given the ice progression and recession depicted
in Figure E.3.2.96.If the chum embryos are
sufficiently developed prior to a breaching
event,no significant effects on development of
E-3-2-20l
the embryos or mortality is anticipated due to
altered temperatures as discussed in Section
2.3.l.c.ii.
If ice formation and subsequent breaching of the
site occurs early in the season,some excess
mortality and possible developmental
abnormalities may occur.However,the mortality
and abnormal development associated with such
events is not expec ted to be greater,overall,
than under natural conditions.This is due
principally to the fact that sites upstream of
RM 133 are not expected to be breached with zero
degree mainstem water and,hence,no mortality
due to zero degree water intrusion,freezing of
the substrates or dessication is expected under
pro j ec t cond i tions •
•Effects On Other Evaluation Species/Habitat
Combinations (***)
Upstream migration of adult chinook salmon into
the ,middle reach occurs in late June and July.
During this period,temperatures due to Stage II
operation are expected to be the most different
from natural water temperatures.Some delay in
the rate of ups tream migrat ion is expec ted.
However,the range of temperatures expected is
wi thin ..thetoler.ance~-range for~adultchinook
migration (Figure E.3.2.98)and,therefore,the
adults are expected to reach the tributary
spawning habitats within the normal time period.
Upstream migratl.on of adult spawning sockeye
salmon may be delayed slightly as a result of the
altered temperature regime due to Stage II
__'.....____,_.9per_a~i0.!l._~.!~_ver...L the mains tem temperaturesexpected'cfurl.ng .S ta geII"op-eratIon-arewrthlnthe--
'~'------tolerance range ror migration of"SocKeye --(Figure
E.3.2.99).
Spawning and incubation of sockeye adults and
embryos occurs exclusively in side slough and
side channel habitats (Representative Groups 2
and'3).Since <spawning and incubation habitats
for sockeyeare'coincident wi th chum spawning and
",'TilcubatiOu'hab'itats",the effects of the''altered
temperature and ice regimes on sockeye are
expected to be the same as those described for
chum.
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851021 E-3-2-20 2
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851021
Juvenile sockeye remain in side sloughs,move to
upland sloughs or outmigrate to the lower river
after emerging from the natal areas.For those
juveniles which move out of the natal areas into
upland sloughs,water temperatures in the
mainstem may retard or inhibit the movement.
However,once into upland sloughs,water
temperatures are independent of mainstem
temperatures (ADF&G 1983k,1984u)and,therefore,
no effects on rearing or overwintering are
expected.Effects on juvenile sockeye which move
out of the middle river are discussed in Section
2.3.2.c.iii.Mainstem temperatures throughout
the summer months are expected to be within the
tolerance range for juvenile sockeye (Figure
E.3.2.99).However,some delay in the
outmigration of Age 1+sockeye.could result~from
the lower temperatures (AEIDC 1984b).However,
the delay is not expected to result in increased
mortality of juveniles in the salt water
environment.
The rate of upstream migration of coho adults may
be retarded to some extent as a result of the
reduced water temperatures attributable to Stage
II operation.However,spawning of \:he .."adult
coho in tributary habitats is expected to occur
within the time frame spawning occurs under
natural conditions.
Redistrihution of juvenile coho fro~the
tributaries into upland sloughs may be delayed to
some extent because of the cooler mainstem water.
However,because mainstem temperatures are
expected to be approximately the same or slightly
warmer than tributary water temperature,no
adverse effects on the redistribution is
expected.The range of mainstem temperatures is
expected to be within the tolerance range of coho
juveniles (AEIDC 1984a;Figure E.3.2.100).Since
water temperature in the upland sloughs is
independent of mainstem water temperature (ADF&G
1983k,1984u)changes to mainstem water
temperature due to Stage II operation are not
expected to affect coho rearing and
overwintering.
Outmigration of juvenile chum salmon generally
occurs over a two month period in June and July.
Juvenile chum generally outmigrate relatively
E-3-2-203
slowly and grow to some extent prior to leaving
the middle river (ADF&G 1983m,1984c,1985c).
The lower water temperatures resulting from
operation of Stage II may slow the rate of
outmigration to some extent and may reduce any
growth which may occur in the middle reach.
Expected temperatures in the middle river are
within the tolerance range for juvenile chum
(AEIDC 1984b)(Figure E.3.2.l0l).Because
juvenile chum do outmigrate relatively slowly
under natural conditions,a delay in outmigration
from the middle river of 1-2 weeks is not
expected to have significant ad verse effec ts.
Also,since outmigrating chum salmon range in
size from newly emergent fry approximately 49 rom)
to approximately 65 rom total length,a reduction
in the growth rates in'the middle reach is not.
expected to adversely affect the population.If
additional growth is necessary to promote
survival of the juveniles in saltwater,
additional growth is likely in habitats
associated with the lower river (ADF&G 1985c).
As with the other salmon species,upstream
migration of pink salmon is expected to be
delayed somewhat as a result of~the lower
mainstem temperatures associated with-Stage II
operation.During operation of Stage II,water
temperaturesthrough~thesummermonths~are~.
expected to be within the tolerance range for
.pink salmon migrat ion.(AEIDC 1984b)(Figure
E.3.2.102),henceany'de1ay in the upstream
migration due to temperature effects is not
expehted to cause significant changes in the
spawning period of pink salmon.The majority
(more than 95 percent)of the pink salmon
spawning and incubation occurs in tributary
"'habrta-tsWh-ich'-wHTno'thearfectec!'hy'maTiisfeIli"'
--_.__.__..._~-_.------,---,--.---,------------.temp'er at,ures.OU tmigrat-ion of-p~nk-juveniles-------
occurs in late May and early June immediately
after breakup of the ice cover under natural
conditions.Since the river is expected to be
ice free as early as late March,outmigration of
pink juveniles is not expected to be adversely
affected.Even though mainstem temperatures in
May and June are expected to be 2-6°c lower than
natural,it is expected that the mainstem
temperatures will still be higher than the
tributary temperatures.Hence,outmigration of
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851021 E-3-2-204
851021
juvenile pink is not expected to be adversely
impacted during Stage II operation.
Rainbow trout,Dolly Varden and Arctic grayling
generally move into tributary habitats to spawn
and rear during the summer months.Therefore,
the expected lower mainstem temperature will not
affect these species.During the winter months,
adults and juveniles of all these species move
into mainstem and mainstem associated habitats.
Since water temperature in much of the middle
river will be higher than under natural
conditions,temperature induced changes in
survival rates of rainbow trout,Dolly Varden and
Arctic grayling are not expected to be
detrimental when compared to natural conditions.
Project induced thermal changes may even enhance
survival of these fishes.
Little is known of the effects of temperature on
burbot growth,spawning and incubation.Lower
summer temperatures could retard growth of
burbot.However,since burbot are found in large
lakes within the area,where they would
e~perience lower water temperatures,the lower
temperatures are not expected to adversely affect
the population.Similarly,warmer temperatures
in the late fall and winter,particularly
upstream of approximately RM 130,are not
expected to adversely impact the population.
-Effects of Altered Suspended Sediment Regime (***)
The effects of an altered suspended sediment regime
during Stage II Operation conditions will be
similar to that described in Stage I Operations
(Section 2.3.1.c.ii).Estimated suspended sediment
concentrations and turbidity values expected in the
discharge from the Devil Canyon Reservoir during
Stage II operation are presented in Table
E.3.2.102.The major change is that Devil Canyon
Reservoir will trap additional portions of the
suspended sediment discharged frm the Watana
Reservoir.Average annual turbidities downstream
will be slightly less than during Stage I
Operations (Table E.3.2.86).
Also,concentrations of suspended sediment will be
slightly less during Stage II (Table E.3.2.102)
than during Stage I operations (Table E.3.2.86).
E-3-2-20 5
The direct effects of the suspended sediment
concentrations on fish in mainstem and peripheral
habitats will still be stressful,but are not
expected to be lethal.Vertical illumination will
slightly increase due to slightly lower turbidity.
The reduction in suspended sediment concentration
and turbidity will allow more extensive periphyton
and epilithon colonization along shallow riffles
and margins of the mainstem channel and in shallow
peripheral habitats chronically inundated with
turbid water.
In general,detrital,primary and secondary trophic
levels will be slightly enhanced in middle river
habi~ats over the produc tion expected during Stage
I operation.Peripheral habitats not chronically
affected by turbid release waters are expected to .
be as productive or more productive at most trophic
levels during Stage II operation compared to
productivity during Stage I operation.The major
reason for this is the net removal of increasing
_a,IIlQ~nl::~_gtf:i.tl~paJ::l:::i.culates from the surficial
streambed substrates.
As previously described,tributary habitats will
not be affected by Stage II or any other
operational flows from the project.
-Effects of Other Water Quality Changes (***)
No additional water quality changes due to Stage II
operations are anticipated to cause biologically
important habitat changes within the middle river
reach.
Dissolved and particulate organic materials of
allochthonous origin are expected to increase in
concentration during-the-fil-lingand-theearly
-------.-..------.------oper.,.at-iona-I---year.-s-o-f-De:v-i-I-Canyon--Resel:-voi-r-.----These
concentrations of organic materials will gradually
decline in waters released from Devil Canyon as
their rate of erosion and leaching from the newly
inundated impoundment zone decreases.Long term
effects associated with these increased organics
areexpec:tecL_to_be n.egligi.ble wi.th respect to
aquaticbiologicalconnnunities located downstream.
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851021 E-3-2-206
..------_..._._.._-_.-._-....._--_......."......-._-------
851021
(iii)Talkeetna to Cook Inlet (***)
-Effects of Altered Flow Regime Stage II (***)
As discussed in Section 2.3.2.c.ii,little change
in the discharge regime in the lower river is
expected between Stage I and Stage II operation.
The lack of difference in the discharge regime is
due primarily to the limited storage capacity in
Watana Reservoir.The discharge regime during
Stage II operation will,however,be different from
the natural discharge regime.Monthly average
discharges at the Sunshine and Susitna Station
gages during Stage II operation are presented in
Chapter 2 Section 4.2.3.a.Maximum,minimum and
mean averaga monthly discharges are summarized here
in Table E.3.2.103 for the Sunshine S.tation and in
Table E.3.2.104 for the Susitna Station.The same
values for the natural flow regime are presented in
the tables for comparative purposes •
•Effects on Principle Evaluation Species/Habitat
Combinations (***)
Because the discharge regime in the lower river
during Stage II'operation will be nearly the
same as during the Stage I operation,no·
additional effects,attributable to the altered
flow regime are expected.Changes to chinook
rearing habitats (Table E.3.2.89)and chum
spawning habitats in the lower river between
natural and Stage I flow regimes will be
maintained through Stage II operation •
•Effects on Other Evaluation Species/Habitat
Combinations (***)
As discussed above,no additional changes to the
other evaluation species/habitat combinations
are expected as a result of Stage II operational
flow regimes.Habitat conditions influenced by
ma ins tem discharge for other anadromous species
life stages and resident species are expected to
remain the same as during Stage I operation (See
Section 2.3.1.c.iii).
-Effects of Altered Temperature/Ice Regime (***)
Water temperature differences between Stage II
and Stage I operation downstream from the
E-3-2-20 7
851021
Chulitna River confluence are expected to be ,
considerably reduced due to the influence of the
colder water in the Chul itna and Talkeetna Rivers.
Differences of up to 2°C during the summer are
expected and are within the natural variation
occurring in the reach (see Tables E.3.2.81 and
E.3.2.82 and E.3.2.99 and E.3.2.100).During the
fall,warmer than natural temperatures will prevail
until late October or early November.After that
time,water temperatures are expected to remain at
O°C through the winter with an ice cover forming
throughout the lower reach.Initial formation of
the ice bridges in the lower river is expected to
occur at approximately the same time as under
natural conditions.Progression of the ice front
upstream from the Yentna River to Talkeetna will
progress somewhat slower.The ice front is
expected to reach Talkeetna in late December.
Because temperature differences between Stage I and
Stage II operation are not expected to be
significant,no impacts to salmon,other anadromous
fish or resident fish resulting from temperature
changes are expected.Principal habitats used by
various life stages of salmon are more likely to be
influenced by other factors such as tributary
temperature and slough temperatures which are
independent of mainstem water temperatures (ADF&G
1985d,1985g).
-Effects of Altered Suspended Sediment Regime (***)
Conditions in the lower river during Stage II
Operations are essentially like those described
for Stage I Operations (Section 2.3.1.c.iii)except
that the.suspended sediment concentrations and
turbidity values are expected to be lower.
Dtrecfeffec t-Son-'iTsh'wln.st i 11 be st:res s £ur~buE
··----notletlia~Lower 'troplficlevels are expectea--to'
be more productive than natural conditions during
June through August,but less productive than
during natural conditions from September through
May.The indirect effects of changes in the
temporal regimes of the lower trophic level
activities'on·the 'fisheries populations is
unknown.The rnost d~tri,lI1enta1 effec ts envisioned
.....are"p<j'teH:ft'ial-r'educt'ii:>nff'in .annual prima ry and
secondary biomass production in relatively deep and
chronically turbid mainstem and large side channel
habitats.
E-3-2-208
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-Effects of Other Water Quality Changes (***)
No additional water quality changes (other than
those previously mentioned)due to Stage II
Operations are anticipated which would cause
biologically important habitat changes in the lower
river reach.
(iv)Cook Inlet Estuary (***)
Lower suspended sediment concentrations and lower
turbidities will enter the Cook Inlet estuary on a
continuous basis due to Stage II Operations than for Stage
I.No important biological effects are presently
anticipated.-Because of strong water currents and high ion
concentrations in the inlet,riverine borne particulates
will be relatively rapidly dispersed,diluted and
precipitated.
Cd)Summary of Impacts Associated with Devilt>:.Canyon Stage II
Dam (**)
(i)Construction Impacts (***)
·As with Stage I Watana Dam,the m9st significant
long-term impact associated with Devil Canyon Dam
will be the increase in fi~hing pressure.Other
impacts resulting from construction activities will
be transitory and are not expected to significantly
affect fish populations.
(ii)Reservoir Filling (**)
Filling the Devil Canyon reservoir will inundate
portions of clear-water tributaries,two of which
(Tsusena and Fog Creeks)presently provide summer
I habitat within the reaches to be inundated for,i approximately 1100 gray ling longer than 8 inches
(20 cm)Table E.3.2.24).Aquatic habitats in the
reservoir are expected to support more productive
resident fish populations than those in the Watana
reservoir because of the timing arid magnitude of the
annual draw-down cycle.The reservoir will be filled
while maintaining Case E-VI flow constraints
downstream.Downstream impacts are not expected
during this period.
851021 E-3-2-209
(iii)Operation Impacts (**)
No significant impacts (other than those imposed by
filling)are expected upstream from Devil Canyon
Dam.The reservoir is expected to support very
limited populations of lake trout,Dolly Varden,
Arctic grayling,burbot,whitefish,and longnose
sucker.
The most significant downstream impact resulting from
the addition of Devil Canyon Dam will be the change
in winter water temperature,which will result in the
maximum ice front extent to be near RM 133 in an
average year as compared to RM 139 in Stage I.The
maximum upstream extent of the ice .cover may be a few
miles downstream or upstream of this in a warmer or
colder winter,respectively (Exhibit E"Chapter 2,
Section 4.2.3(c)(ii).The river stage in the
open-water reach will be lower than the stage present
under an ice cover.This ,.change will reduce
available habitat in areas that previously formed an
ice cover,as was discussed for impacts associated
with Watana Stage I Dam (Section 2.3.1.c).
With the addition of impacts of Devil Canyon Dam,
.habitats between Talkeetna and Cook Inlet are not
expected to increase over conditions for Watana Stage
1.
2.3.3 -Anticipated Impacts on Aquatic Habitat Associated With
Stage III -Watana/Devil Canyon Dams (***)
Stage III of the development of the Sus itna Hydroelectric Projec t
will consist of raising Watana Dam such that the normal minimum
operating water surface elevation is at el.2,185.The Watana
reservoir is expected to begin filling in year 2011 and the Stage
III will become operational in 2012.Once the reservoir is full
··~·~----atfd--(Yp'era·tional-;-the'proje'c-t···-wi'U;--be--nearty-~the~'s-ame--~as-the'-~---"'"
.-.....---_.--.'--~--~·-comple·ted-proJec·t-de·scribed----in-the-ori-gi-n-a'l----r..icense-App-l--ica·t-ion·..._-
(APA 1983b).
Impacts on aquatic habitats as a result of construction of the
Stage III WatanaDam will be of lesser magnitude than those
occurring during the construction and operation of Stage I or
Stage ..II •.LittLe.ornoinstream workwilLberequired and the
support facilities will already be in place.Filling of the
reservoir to e1.2,185 will req uireapproximately three to seven
years and will increase the effects of the Watana Reservoir
further upstream in the mainstem and tributaries.
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(a)Construction Impacts Stage III (***)
(i)Watana Stage III Construction Effects (***)
The period of construction considered for the
proposed Stage III Watana Dam consists of those
activities related to the initial lowering of the
reservoir to allow for the raising of the dam,the
spillway and the intake structures and the raising of
the reservoir to el.2,185 feet.An additional 27.5
million cubic yards (21.1 x 10 6 m3 )of material will
be required to construct the Watana Dam to its
ultimate height of el.2,205 feet.During the
construction of Stage III,river diversion will not
be required.Operation of the power facilities would
continue during construction of Stage III.
-Alteration of Water Bodies (***)
The greatest alteration of aquatic habitat during
construction of Stage III Watana Dam would again be
the borrow activities at Borrow Site E at the
mouth of Tsusena Creek.The degree of change will
depend on the mining procedure used to remove the-.
material needed to comple te th is stage of the.
project.Removal of riparian and~upland material
will increase the surface area of the lake created;c
by Stage I mining activities;a dredging operation
will result in a deepening of the lake •.Both
operations will result in temporary increases in
turbidity and sedimentation in the lake,the
introduction of small amounts of hydrocarbons from
equipment,and a permanent change in the
geomorpholo'gy 0 f the lake.BMP manual guidelines
and techniques (APA 1985a)will be incorporated
into contractual documents to ensure that the
environmental goals of the Applicant are met.
-Water Quality Changes (***)
The movement of fill materials and the process of
constructing the Stage III dam will contribute to
an increase in turbidity and sedimentation.
Introduction of material into the mainstem Susitna
River will be less severe than during Stage I due
to the smaller total volume of material deposited
for dam construction.Some material will settle
out in the Watana Reservoir,further reducing the
influx of material into the mainstem Susitna River.
Some material will pass downstream during
851021 E-3-2-2l1
851021
construction but most of this will become trapped
in the Devil Canyon Reservoir preventing .any
increase in siltation or sedimentation rates in
anadromousfish habitats downstream.
The production of concrete for raising of the
spillway and power intake,and for grouting will
generate.concrete-batching waste water.Adjustment
of the pH of this waste water will be necessary to
prevent detrimental effects.on fish populations and
habitat.The measures that will be taken to
minimize concrete contamination of the water during
Stage II construction are discussed in Exhibit E,
Chapter 2,Section 4.3.1Cc)(vii).
The possibility of contamination of waterbodies by
petroleum products is similar to that.during Stage
I construction.Fuel leaks,vehicle accidents,and
handling of hazardous materials (sol vents,
antifr~eze,hydraulic oil,paints,waste oil,and,
grease).are possible sources of petroleum
c:ont:.l3.mJtlat:i.()Il~,.B~.!n§.tlu.l3.:.t techniques and
guidelines (APA 1985b)incorporated into
contractual .documents will reduce or elminate the
possibility of impacts from these sources.
-Other Effects on.Fish Populations (**)
______.,~c"(Vithd-Eawa~.2.L~~J:e::s_H_0!!1=~~~a.~_s()tl'J:'~~~~()y.:_...
production of concrete,processing of gravel,and
dust control could result in entrainment and
impingement of j:uvenile fish.Use of low volume
pumps equipped with proper intake screens will
minimize the numberq f,£ish affected.Dewatering
fish habitat in either the summer or winter low
flow period could occur,but will be minimized by
pumping from streams .with relatively high flows.
·-Nocc-ins·E-l"eam-bl·as·t-i-ng-,-i-s-e.u'l:-l"ent-ly····pl·anned.•................---....,......
Blasting for areas 500 feet or more from streams
may occur.Such blasting may disrupt normal fish
behavior temporarily,but no mortalities are
anticipated.Secondary e~fects of blasting may
include increased tUJ:'bidity and siltation of
str.eamsby loosened.dirt and dust.The extent of
such effects wquldciep~ndupon the location and
amount Of·bl a.stirig~.:....~_c •••••
E-3-2-2l2
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(ii)Operation of Stage III Watana Camp,Village and
Airfield (**)
During peak construction activities for the Stage III
Watana Dam,facilities to house approximately 2,000
people are anticipated.The same facilities used
during Stage I will be reopened for Stage III.
A 6,500 foot permanent airfield will be available for
use during Stage III construction.
Impacts associated with reopening the camp will be
significantly less than during its construction.
-Alteration of Water Bodies (***)
Operation of the camp and airfie~d is.not expected
to result ~n the alteration of waterbodies.
Water for camp use will again be withdrawn from
Deadman Creek,with little or no impact on fish
habitat (see Section 2.3.1.ii)•
.-Water Quality Changes (***)
During camp operations,the most significant
impacts on water quality will result from discharge
of treated wastewater into Deadman Creek,oily
and silty runoff from the camps,water used for
dust control,and accidental fuel spills.Section
2.3.1 (ii)describes these impacts in details.
(b)Anticipated Impacts on Aquatic Habitats of Filling Stage III
Watana/Devil Canyon (***)
Filling of Watana Reservoir from el.2,000 to el.2,185 will
require approximately three to seven summers to complete.
During this period of time,discharge from the reservoir
will be maintained within the E-VI constraints.During the
filling period,effects of the reservoir will be extended
upstream in the mainstem and tributary habitats.Downstream
of the project,the effects will be similar to those
encountered during operation under Stage II.Therefore,
detailed discussions of the habitat conditions in the
reservoir and downstream from the project are presented in
Section 2.3.3.c,Effects of Operation of Stage III
Watana/Devil Canyon Dams.A brief description of the
filling of Stage III Watana Reservoir is presented here.
851021 E-3-2-213
851021
(i)Watana Reservoir Filling (***)
During the operation.of Stages I and II,the annual
refilling of the Watana Reservoir was complete when
the reservoir water surface elevation reached
el.2,000 ft.After the reservoir was filled excess
inflow was released downstream.Once the Watana Dam
is completed to its full height,the inflow,
previously released,will be stored and the water
surface will be allowed to rise to el.2,185 ft.
Because the storage volume in the upper 185 ft.of
the reservoir is quite large,it will require three
to seven summer filling cycles to raise the water
surface to the maximum level.As the reservoir is
filled above el.2,000,additional mainstem tributary
and lake habitats will be inundated.Since the
reservoir and dams will be operated to generate power
during this period,the effects of the impoundment
are appropriately discussed in Section 2.3.3.c.i.A
comparison of the area td be inundated once the
reservoirach ieves el.2,185 with the reservoir area
at eL'2,000 is presented in Figure E.3.2.103.
(ii)Devil Canyon to Talkeetna (***)
-Effects of Altered Flow Regime (***)
Discharge from Watana and Devil Canyon Dams will
-------rema-:i:n~~wi-th-in~t;he Gacse-E-V-I--f10wc0nst.'Eai-n,ts
throughout the filling of the Stage III Watana
Reservoir.However,flows wi 11 generally be near
the Case E-VI minimum constraints during the
summers'of fi 11 ingas water normally released
through the outle t works will be.used to raise the
water level in Watana.Because the project will
remain operational during filling discussion of the
...:i,!!1P.li_c:::ts.~:i,U_J;>,~_!:h ~_,~.!i~_....a s ,_t;h.!i.~__()_~~_~E:~.,~E~_l:.a~_~_<:)E.a_l
effec ts.Therefore,the effects of the al tered
flow regime on the principle evaluation----~----~--
species/habitat combinations and the other
evaluation species/habitat combinations in the
middle river are discussed under the effects of
operation of Stage III in Section 2.3.3.c.ii.
"-"'Effectsof Altered Temperaturellce Regime (***)
"'fiiiii'ng EheiTiTli ng'o£'St-a-ge-tITWa tifi:i8 Res e tva it ;
the capacity to selec t the water temperature to
be discharged will be maintained and the outlet
works releases will be minimal.This,in
E-3"';'2-214
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.851021
combination with the flows which are redcued from
operation of Stage II will result in warmer
downstream temperatures in the summer than in Stage
II (see Exhibit E,Chapter 2,Section 4.3.2(d)(i».
Because the project will be operational during the
filling of Stage III,discussions of the
temperature differences and the effects on
evaluation species/habitat combinations are
appropriately presented as part of the effects of
Stage III operation in Section 2.3.3(c)(ii).
-Effects of Altered Suspended Sediment Regime (***)
The Stage IiI filling process involves raising
maximum reservoir surface stage from el.2,000
MSL to el.2,185 MSL.During the three to seven
year filling period for Watana Stage III,the
project will still be generating power.During the
Stage III filling process the maximum Watana
Reservoir water surface elevaeions may increase by
between 75 and 25 feet per year each year the rate
decreasing with each year as filling approaches the
range between el.2,000 and el 2,185.Erosion of
particulates from the fluctuating reservoir
shorelines is expected to contribute an additional
unquantifiable amount of suspended sediment and
turbidity to the reservoir water.At present this
addition of suspended particulate material is
expected to be minimal when compared to that
derived from riverine influents.
As a consequence of the previously mentioned
ercosive actions,slightly increased levels of
suspended sediment and turbidity will be
measureable in waters released from the Watana and
Devil Canyon Reservoirs during Stage III filling.
However,the effects on the downstream aquatic
biological community are expected to be negligible
and relatively shortlived.In general effects will
be similar to those discussed under the Stage I
filling and operations sections.
-Effects of Other Altered Water Quality
Factors (***)
No additional water quality changes,other than
those previously discussed in Exhibit E,
Chapter 2 and previous sections of Chapter 3,are
expected during Stage III-Filling.Effects on
E-3-2-215
851021
aquatic biological communities downstream from the
Devil Canyon Dam are expected to be negligible.
Increased concentrations of particulate organic
carbon (POC)and dissolved organic carbon (DOC)are
expected to occur in downstream releases due to
inundation,erosion,and leaching of a110chthanous
organic matter from newly inundated shorelines.
Increased organic matter concentrations in project
releases will likely serve as an additional
nutritional base for detritus processing microbial
and macroinvertebrate populations in downstream
riverine habitats.The effects of the increased
organic nutritional base,however,are not expected
to be long-lived in relation to the project's
operational lifetime.,nor are the effects expected
to be quantifiable with respect to the riverine
fish community.
_(iii)Talkeetna to Cook Inlet (***)
-Effects ·o·f Altered Flow Regime (***)
Effects of changes to the flow regime in the lower
river during filling of Stage III Watana
Reservoir will be essentially the same as the
effects of operation of Stage III.The effects of
the altered flow regime during filling of Stage III
Watana-Rese,y;voir--in'-cthe~10wer-riv-erare,-therefore,
appropriately discussed in Section 2.3.3.c.iii.
-Effects of Altered Temperature/Ice Regimes (***)
As discussed previously in Section 2.3.3.b.ii,
water temperatures in the middle river and,
therefore,the lower river are expected to be
somewhat warmer during filling and operation of
'-"'SEageIII-tiian-<fu ring"'op eratIon-'o'fSta-ge--fI .
Because the projec t wl.Il continue-operation-Enrougn
the filling of Stage III Watana Reservoir,the
effects of altered temperature/ice regimes on
aquatic habitats in the lower river are
appropriately discussed in Section 2.3.3.c.iii of
Stage III of the project.
-Effects of Altered-Suspended Sediment Regime (***)
During the months of May through September the
suspended sediment concentrations of the middle
river reach will be less than the normal amount of
E-3-2-216
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851021
suspended sediments occurring under natural
conditions.With-project flows from the ~iddle
ri ver reach may dilute TSS concentrations
downstream of RM 96 during the summer.Changes in
the suspended sediment regimes in habitats in the
lower river during May through September,however,
are not expected to be biologically significant
because of the influence of the Chulitna,Talkeetna
and other glacical tributaries.
During the winter the suspended sediment
concentrations and turbidities of the middle river
reach will be greater than the natural levels.
With-project flows from the middle river reach will
increase TSS concentrations and turbidity values
downstream of RM 96.However,the biological
effects of the TSS concentrations during the winter
are expected to decrease with increasing distance
downstream from the mouth of the middle reach
(RM 98.5)because of the dilution by the relatively
clear water from the lower river tributaries.
Biological effects are expected to be limited
primarily to riverine habitats directly affected by
mainstem flows and ice processes.
Direct effects on resident and rearing juvenile
fish are expected to be stressful,but not lethal.
Indirect effects to fish because of changes at
lower trophic levels are both unpredictable and
unquantificable.
Tributary habitats,as previously noted,will not
be affected by Stage III-Filling.
-Effects of Other Altered Water Quality Factors (***)
Additional water quality changes due to Stage
III-Filling that have not already been disc~ssed,
which will cause biologically significant habitat
changes within the lower river reach.
As previously discussed,concentrations of POC and
DOC are expected to increase in lower river
habitats inundated by riverine flows which are
influence by Stage III-Filling releases.The
anticipated increased organic matter concentrations
in lower river aquatic habitat will likely serve as
an additional organic nutritional base for
microbial and macroinvertebrate detritus
processors.As discussed previously (see middle
E-3-2-217
river discussion sections),these effec ts are
expected to be short-lived in relation to he.
project's operational lifetime and their effects
are expec ted to be negligible wi th respect to the
lower river fish community.
(iv)Estuary at Cook Inlet (***)
StageTII-Fillng effects on the Cook Inlet estuary
area at the Susitna River mouth are expected to be
1 imited to mildly increased fertilization of
biological production during the winter.The mild
fertilizationeffec t is expec ted to be due to
nutrients associated with the suspended particulates
carried to the estuary by constantly turbid riverine
flows.
As discussed previously,high marine environment ion
concentrations and relatively strong inlet currents
will rapidly disp.erse,dilute and precipitate the
suspended particulates.Ecological effec ts on the
inlet are expected to be minimal.
(c)Anticipated Impacts on Aquatic Habitats of Operation of
Stage III Watana/Devil Canyon Dams (***)
The impacts on aquatic habitats during operation of Stage
III of the Susitna Project are continuations of the impacts
associated with Stage II.Some changes to the reservoir
operatlons·wInbeimpIem.~nEedas'de-scrrbedTii Sect fon'---
2.3.3.c.i,below.Changes to the flow regime will result
from the increased capacity to generate power as a result of
StageIII.The flow regime,however,will remain limited by
the Case E-VI constraints.
(i)Impacts of Stage III Watana Reservoir
Operation (***)
------···-Gomple--t-ion-o·f-t-he··Scta·ge-;-I-I-I-Wa·t-ana··nam··w-i·l·l---ra-i·se··the--········_··
reservoir to a normal maximum water surface el.of
2,185 ft MSL,the same elevation proposed in the
original License Application (APA 1983b).The Stage
III Watana Reservoir will-increase the total
inundated reacllesof theSusitna River to 48 miles
(54 miles along the river ·befo re impou nding)•The
lengths of reaches of,the four named tributaries
af:fectedby=th e"Sfage:r:reservoi rwi l.lbe.increa sed
and the lower portions of two additional tributaries,
Goose Creek and Oshetna River,will be affected
(total of 11 mi additional).TWenty-four additional
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851021 E-3-2-218
./-
851021
lakes and ponds will be inundated by the higher
Watana Reservoir including Sally Lake,a 55 acre lake
located near the confluence of Watana Creek with the
Susitna River.The maximum surface area of the
Watana Reservoir will be increased by 17,000 acres to
a total surface area of 38,000 acres.The Stage III
reservoir area is depicted on Figure E.3.2.103.
The drawdown-refill cycle of the Stage III reservoir
will be similar to the cycle described for the Stage
I reservoir.A major difference is that the maximum
drawdown under Stage III will be 120 ft.rather than
150 ft.This difference is due p.rimarily to the
larger volume of water per foot of depth with higher
water surface elevations in the reservoir.The
average rate of drawdown in the reservoir will be
decreased to 0.5 ft.per day and the average rate of
rise in the surface elevation during refill will
decrease to 1.0 ft.per day.A schematic of the
drawdown-refill cycle in Watana Reservoir during the
early years of Stage III operation and _when the
project is operated at full ..capacity in later years
of project operation is presented as Figure
E.3.2.104.
Devil Canyon Reservoir will also be drawdown
periodically in a manner similar to that de,scribed
for Stage II operation.A schematic of the expected
drawdown of the Devil Canyon Reservoir in early Stage
III operational years and late Stage III operational
years and is presented as Figure E.3.2.l05.
With the increased length of the reservoir due to
construction of the Stage III Watana Dam,the
deposition of sediments will occur primarily the
newly inundated reaches of the Susitna River.
Deposition and redistribution of the sediments will
be similar to those described for the Stage I Watana
Dam and Reservoir.Turbidity in the larger reservoir
will approximate that described for the Stage I
reservoir.Turbidity in the downstream portion of
the reservoir may be somewhat less than with the
Stage I due to the increased storage capacity and the
consequent increase in the residence time of the
water.
The water temperature regime in the larger Stage III
reservoir will be similar to that described for the
Stage 1.
E-3-2-2l9
-Effects on Mainstem Habitats (***)
With the raising of the Watana Reservoir,mainstem
habitats,upstream to approximately RM ,will
be inundated.Additional burbot,and longnose
sucker habitats will be inundated with end results
similar to those described for the Stage I
reservoir.Also,additional overwintering habitats
for Arctic grayling and Dolly Varden will be lost
as a result of the impoundment.
-Effects on Tributary Habitats (***)
At the maximum water surface elevation of the Stage
III Watana Reservoir at el.2,185 ft.MSL,the
reservoir will be extended further into the
tributaries previously affected by the Stage I
Reservoir.Also,the Stage III Reservoir will
affect two additional named tributaries.The
locations,lengths and gradients of the tributaries
affected by the Stage III Reservoir are summarized
in Table E.3.2.l05..The,increases from the Stage I
and Stage II reservoir in the lengths of the
tributaries affected by Stage III are also
presented.
Although the total lengths of tributaries inundated
by the reservoir will increase after Stage III is
complete.d:,~the ..lEmgtb_sQ:L the .tJ"i.butal:'i.~lLwithJn
the drawdown zone will be less.This is because
the reservoir will not be drawn down as far.
Summaries of the tributary lengths in the drawdown
zone that are permanently inundated are presented
in Table E.3.2 .105.
Based upon the estimated populations of the Arctic
grayling in the tributaries under natural
·con.ditions-an···addiEiona14;-OOO-fislf·win-be
.~_-~--_-..--.-----.~-----_..-.-a-ffc:fc-te-d-by-rars-ing-Wae-ana-Res-ervoi-r-to--el':'.·-2,1~85~;-~----
Most of the additional fish affected by the higher
reservoir inhabit the Oshetna River and Goose
Creek.The actual populations affected by the
Stage III reservoir will be dependent,in part,on
how well grayling populations succeed in the Stage
I Reservoir.
1
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851021 E-3-2-220 I)
851021
-Effects on Lake Habitats (***)
As stated previously,24 additional lakes and ponds
will be affected by the St~ge III Reservoir.The
only lake known to support fish populations is
Sally Lake.This lake has populations of lake
trout and grayling that appear to be stunted (ADF&G
1981f,1983b).Since grayling populations are not
usually associated with glacial lakes or turbid
water,they will likely be lost.Lake trout will
be able to survive in the reservoir if an adequate
food base exists.Lake trout are found in glacial
lakes,incl uding Chakachamna and Kontrashibuna
Lakes (Bechtel Civil and Minerals,Inc.1981,
Russell 1980),with physical characteristics
similar to those expected in the Watana reservoir.
(ii)Devil Canyon to Talkeetna (***)
-Effects of Altered Flow Regime (***)
When Watana Dam is raised to its full height,the
Watana Reservoir maximum water surface elevation
will be raised to el.2,185.Since this additional
height will greatly increase the storage capacity
of the reservoir,the capacity of the project to
regulate discharge in the river will also be
increased.During the early years of operations of
Stage III Watana Dam (i.e.once the reservoir is
filled),the discharge regime is expected to be
quite similar to that experienced during Stages I
and II.This flow regime is characterized by some
annual variation in discharge wi th somewhat higher
discharges occurring in the summer months than in
winter months.As the demand for energy increases,
discharge from the Watana/Devil Canyon Dams will
gradually assume a more constant discharge through
the year.In other words,discharge during the
winter months will gradually increase as demand for
power increases.Additionally,demand for power
during the summer months will also increase.As a
result,more of the inflow to the Watana Reservoir
will be required for generation of electric power.
Hence,the time required for refilling the
reservoir during the summer months will be extended
and the mean discharge during the summer months
will gradually decline toward the minimum flows
allowed by Case E-VI.When the demand for power
reaches the total capacity of the project,
discharge from the dams will be nearly constant
E-3-2-221
851021
through the year as indicated by the discharge
presented in Table E.3.2.106 for the late years of
Stage III operations.
The flow regime associated with initial years of
operation of the Stage III project is represented
by simulation of project operation given a
forecasted energy demand expected to occur early in
the Stage III operational period.For this
purpose,an annual energy demand 0 f 6,100 GWH and
an average annual energy production from the
project of approximately 5,540 GWH was used in
deriving the expected from regime of Gold Creek.
Average monthly discharges from the project for the
34 years of record are presented in Exhibit E,
Chapter 2,Section 4.3.3.a.The possible maximum,
minimum and mean average monthly discharges at Gold
Creek for this demand level are summakized in Table
Eo3.2.106.
It is expected that the demand for power will reach
maximum capacity of the project sometime between
the years 2030 and 2040.In order to evaluate the
discharge regime when the project reaches its
maximum production capacity,an annual energy
demand of approximately 8,300 GWH were and a
maximum average annual energy production for the
system of approximately 6,850 GWH were selected for
._--.e-val-ua-t~i0n-·0·f-·the·f.1-0w-1'-eg·imeass0ciated-·wi-th··the-
maximum energy production possible from project
operation.possible average monthly discharges at
Gold Creek for this demand level are presented in
Exhibit E,Chapter 2,Section 4.3.3.a.
Maximum,minimum and mean average monthly flows at
Gold Creek for late Stage III operation are
summarized in Table E.3.2.l06.-.---'.'--_...---.--_....__..•..,...._--_.-_.-
.·-:-·E-HectsonPrIncipa1~riiatioo·specIeS7HaDiE~it-
Combinations (***)
Chinook Rearing Habitats (***)
Total chinook habitat areas for the summer
·-months were·derivedby translating the weekly
average discharges at Gold Creek for early Stage
........······III-lind·Tate .Stage·III··demand·levels·into
habitat areas,using the chinook rearing habitat
area response curve presented in Table Eo 3.2.46
and Figure E.3.2.64.As discussed previously,
E-3-2-222
-1
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851021
total habitat areas are calculated only for the
summer period,June through September.
During the early years of operation of Stage
III,the total chinook r.earing habitat area will
be similar to that available during Stage I and
Stage II operation.Total habitat areas which
are 90 percent likely,50 percent likely,and 10
percent likely to be equalled or exceeded given
the forecasted energy demand during early Stage
III operation are presented in Table E.3.2.107
and are depicted graphically in Figure
E.3.2.106.Habitat areas estimated for the
natural flow regime are also presented for
comparison.
Comparison of these values with those presented
in Table E.3.2.74 and Table E.3.2.92 indicates
that no immediate change in the total chinook
o
rearing habitat area during the summer months is
expected with initial operation of the Project.
As discussed previously,for Stage I and II,the
total chinook rearing habitat area in the middle
river during initial Stage III operation is
expected to be slightly less than what is
available under natural conditions during the
first half-of the summer.Again,by mid-summer,
when juvenile chinook become prevalent in
mainstem affected areas,the range of habitat
areas available in these areas will be nearly
the same as under the natural flow regime (See
Figure E.3.2.106).However;the week to week
and year to year variation in total habitat area
is expected to be somewhat less under the early
Stage III flow regime than under the natural
flow regime.
As the demand for power increases through time,
summer discharge in the middle river is expected
to decline to an average of approximately 10,000
cfs through the summer (Table E.3.2.106).Even
with the gradual decrease in the summer flow
regime,ototal chinook rearing habitat area is
expected to remain relatively the same through
the summer.Total chinook rearing habitat areas
that are 90 percent,50 percent and 10 percent
likely to be equaled or exceeded,given the
forecasted Stage III flow regime when the
project is operating at maximum capacity,are
presented in Table E.3.2.108 and are depicted
E-3-2-223
graphically in Figure E.3.2.107.Comparison of
the habitat area values for the late Stage III
flow regime with those for the early Stage III
flowiregime indicates a very slight reduction in
the median habitat areas available through the
summer period.The major difference between the
habitat area values for early and later Stage
III operation is the reduction in the year to
year variation in the amount of habitat
available.This is evident particularly during
the months of July and August (Weeks 28-34).It
is important to recognize here that the apparent
reduction in the h.abitat area available from
early Stage III to late Stage III will occur
gradually over 15~20 years.Hence,it is likely
that the juvenile chinook population will adjust
to the change with no appreciable adverse
effect.Again,it is emphasized that the
equivalent habitat area values resulting from
this analysis only indicate the amount of
habitat area.available for use by juvenile
chinook and does not make any prediction as to
whether or not all of the area will be
utilized.
A somewhat di fferent trend emerges if only the
habitat areas included Representative Groups 2,
3,and 4 are considered.Translation of the
...·early··S·~age I-FE·flow regime intohabi-tatareas
were made using the habitat response curve for
the three r'epresentative groups presented in
Table E.3.2.46.Median,90 percent and 10
percent exceedance values of habitat area in the
three representa.tive groups resulting from the
translaHons are presented in Table E.3.2.l09
and are depicted graphically on Figure
E.3.~!JQ~•..gQ1!1p~:cJ..~()tLQtthE!l;E!Yc:JJllE!$w.ith .
similar values for the natural flow regime,also
.....~~..__..--'~---"-'---"--~~~presented in TableE.3.2.l09,8ndforthe S~tage-·
I and Stage II flow regimes indicates that
habitat for juvenile chinook rearing will be
greater under Stage III project operation than
under the natural flow regime.A notable
feature of the rearing habitat areas is that
..·there'isessentially-no week to week and year to
year variation<expected during the first part of
....-...the ··summe-i'-Cthiougo",.'rulY)dtiiirig·£herefiI fing
period.Considerably more variation is expected
during the later part of the summer.
.\
,I
851021 E-3-2-224
851021
Similar results are obtained for the flow regime
expected late in Stage III operation,·once the
energy production from the project reaches
capacity.Median,90 percent and 10 percent
exceedance values of habitat area in
Representative Groups 2,3,and 4 are presented
for late Stage III operation in Table E.3.2.1l0
and are depicted graphically in Figure
E.3.2.l09.Again,total rearing habitat areas
available in the three representative sites will
be greater than under the natural flow regime.
The reduction in week to week and year to year
variation,observed for the first part of the
summer in the early Stage III operation,is
extended through the entire.season.Hence,it
is expected that not only will the available
rearing habitat be greater under project
operation,but the availability will be more
reliable t-han under natural conditions.
During the winter months,Stage III discharge in
the initial years of operation will be similar
to that described for Stages I and II.A
difference that will be observed during the
first years of Stage III operation is that the
ice front wi 11 form somewhat :later and wi 11 not
progress as far upstream than during-·Stage II.1:1
As a result it-is expected that overwintering
habi tats used by juvenile ch inook in the ice
free reach of the Middle Susitna River will
increase because more of the habitat will not be
affected by ice.Consequently,survival of the
juveniles could increase.
In the reach of the river with an ice cover,
staging of the water surface elevation
associated with the ice cover will not be as
great as during Stage I or Stage II and,
therefore,the likelihood that overwintering
habitat areas will be overtopped and influenced
by O°C water will be less.As discharges
increase during the winter months with the long
term increase in the energy demand,the
progression of the ice front is expected to
decrease both in rate and in upstream extent.
Hence,the duration of the open water period in
the reach will gradually increase and the
effects of staging will decrease.In addition,
particularly in the upper portion of the middle
river upstream of RM 130,backwater areas at the
E-3-2-225
851021
mouths of overwintering habitats will increase
due to the higher mainstem discharges-during the
winter.Also,in areas adjacent to ice covered
reaches of the mains tern,rates of groundwater
upwelling will be greater (APA 1984d).
Consequently,it is expected that overwintering
habitat areas will be greater than during Stages
I,II and the initial years of Stage III once
the energy production from the project reaches
capacity.These habitat areas are also expected
to be greater than those available under natural
conditions.The overall result is that
overwinter survival of chinook juveniles is
expected to increase.
Chum Spawning/Incubation Habitats (***)
During the initial operating years of Stage III
of the project,chum access conditions,and
spawning and incubation habitats will be nearly~
the same as that described for Stages I and II
of the p.roj ect.
Access at the mouths of sites traditionally used
by chum for spawning are expected to be nearly
the same as conditions,~during Stages I and II.
The status of.access at selected sites in the
middle river during initial Stage III operation,
~".r~e.p_re~~ent_ed.Qy~t..-l:l.e rangg ..QfgiJi~hJ:!.J::gSLa~.p~c teg
during early Stage III operation (Table
E.3.2.106),are summarized in Table E.3.2.111.
The status of access for maximum,mean and
minimum ayerage monthly discharges in August and
September which occur naturally are also
provided in the table for comparison.Based
upon the evaluation of passage conditions
presented in Table .E.3.2.111,6 passage reaches
...······wil1·.·····present·m6re·~di"fficurt-c·ondi~tionif···than
·-.-n.a.tural-----fo·r~a-·me·an-di:scharge-ye-ar-±n-·Augus·t-;~._ _-..
Only one reach will be more di ffi cul t during
Stage III operation than during natural mean
flows in September.
As the demand for energy increases,average
monthly "discharges..during Augus t and September,
represented by the discharges for late Stage
III,areexpected·to decrease.Consequently,
access conditions at many of the mainstem
affected passage reaches in the selec ted
spawning habitats will deteriorate.The status
E-3-2-226
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851021
of access conditions at the selected passage
reaches given the possible maximum,mean and
minimum average monthly discharges in August and
September expected during late Stage III
operation are summarized in Table E.3.2.111.
Based on these analyses,over half (14)of the
24 passage reaches will present more difficult
conditions than natural under mean discharge
conditions in August.six reaches will present
more difficult conditions in September.When
maximum discharge conditions prevail,seven and
four passages reaches in August and September,
respectively,will present more difficult
conditions.Under minimum flow conditions,no
difference in access conditions between late
Stage III and natural are expected.
The availability of chum spawning habitat area
during the initial Stage III operation,
represented by the probable discharges
associated early Stage III operation,is
expected to be approximately the same as uuring
Stage II operations.Weekly average spawning
habitat area for the early Stage III flow regime
in August and September were calculated from the
average weekly discharges and the total habitat
response curve for sftes traditionally 'used by -
chum salmon for spawning and were included in
the modeled sites (Table-E.3.2.47 and Figure
E.3.2.59).The weekly average habitat areas
that are 90 percent,50 percent and 10 percent
likely to be equalled or exceeded given the
energy demand and average energy production in
early Stage III are presented in Table E.3.2.112
and are depicted graphically in Figure
E.3.2.110.Comparison of these values with
those presented for Stage II operation (Table
E.3.2.95 and Figure E.3.2.90)indicates that,
initially,little change in the available
spawning habitat area from Stage II is expected
during the initial operation of Stage III.The
spawning habitat area available in the
traditional spawning sites during the initial
Stage III operation will be nearly the same as
that available under the natural flow regime.
These are also presented on Table E.3.2.112 and
Figure E.3.2.116 for comparison.Also,the
range of week to week and year to year variation
during the initial Stage III operation will be
E-3-2-227
nearly the same as that which occurs naturally
and under Stage II operation.
As the energy production from the project
reaches capacity,represented by the energy
demand and average energy production expected
during later Stage III operation,average dis-
charge from the project in August and September
will be less (Table E.3.2.l06).The total chum
spawning habitat area in the modeled sites will
also decline.The total·spawning habitat area
in the modeled sites expected to be equalled or
exceeded 90 percent,50 percent,and 10 percent
of the time are presented in Table E.3.2.ll2 and
depicted on Figure E.3.2.lll.Once the energy
production from the project reaches capacity
during late Stage III operation,the spawning
habitat area in the modeled sites will,on the
average,be less in August and will gradually
increase through September.A major difference
in the availability of spawning habitat area is
.that more habitat will be available 90 percent
of the time,represented by the bottom line in
Figure E.3.2.l06.This is due principally to
the fact that peak flows,greater than the
optimum flow,will be reduced in frequency
because the filling of the reservoir will be
achieved later in the year.Hence,high flows
__~.~.in Augus t ~wil Lbestored.in the rese't'voi~r·rat:heI;'
than released downstream as was done during
Stages I and II.The result is that the week to
week and year to year variation in the spawning
habitat area will be less than that expected
duririgStages I and II and during the initial
years of Stage III operation.
A similar analysis was conducted using the..."'--cntilnsp'awrii ng·liabTt-.iErespon·securvefor ···sItes····
..~._-_._~_---"'-'''--'''---incluaea-~inRepresentative 'Groups Z;~-3ancCq:--
presented in Table E.3.2.48 and Figure E.3.2.63.
The total habitat areas in August and September
likely to be equalled or exceeded 90 percent,50
percent,and 10 percent of the time early and
late in Stage III operation are presented in
Tabl.e E.3.2.H3 and are depicted graphically in
FigtJresE.3.2.1l2 arid E.3.2.1l3,respectively.
As'discus sed for the spawning habitat in the
modeled sites,the total habitat area available
in the three Representative Groups is expected
to decline slightly as the flows change from
l
1
851021 E-3-2-228
I
851021
early Stage III to late Stage III ope~ation.
Also,the range of week to week and year to year
variation,particularly during August,is
expected to decrease from early to later Stage
III operation as more time is needed to refill
the Watana Reservoir.
The effects of the Stage III flow regime on the
incubation of chum embryos are similar to those
described for Stage I and II.As described for
the other Stages of development,the total area
that will be maintained through the early winter
months for incubating chum embryos during the
first years of Stage III operation will be
similar to that maintained in Stages I and II.
Again using the assumption that spawning area is
a good estimate of incubation area for chum
embryos,the total habitat areas that are 90
percent,50 percent and 10 percent likely to be
equalled or exceeded in the modeled chum salmon
spawning sites (Table E.3.2.46 and Figure
E.3.2.59)under the early Stage III discharge
regime were calculated.The results are
presented in Table E.3.2.1l4 for the months of
October and November and are depicted
graphically in Figure E.3.2.1l4.
With the increase in the demand for energy,the
winter discharge regime will gradually increase.
As a result,the availability of area in the
modeled sites having suitable conditions for
incubation will also iricrease.This is
indicated by comparing the habitat areas 90,50
and 10 percent likely to occur given the late
Stage III flows with same values for early Stage
III discharges in October and November.The
habitat values for the late Stage III flow
regime are presented in Table E.3.2.1l4 and are
depicted graphically in Figure E.3.2.115.
Another facet of the spawning/incubation habitat
area,given the discharge regime expected during
late Stage III operation,is that habitat
available for spawning in August and September,
even though it is less than that available
earlier in Stage III or under natural conditions,
will be maintained at a constant level into the
incubation period.Hence,habitat sites where
embryos are deposited will not be as likely to
dewater or freeze as under natural or earlier
E-3-2-229
project operational regimes.This is because
under th~other regimes,discharge declines from
the August-September period to the
October-November period.Under the late Stage
III flow regime,habitat area available for
spawning in August and September will be
retained in October and November.Hence,the
survival of chum embryos is expected to
increase.
Another factor leading to the conclusion that
the survival o~the embryos is expected to
increase is that the ice front is expected to
move into the middle river later and not extend
as far upstream during Stage III as under the
natural Stage I or Stage II flow regime.~Hence,
the ice-free habitat area upstream of the ice
front is expected to be greater than under the
other flow regimes.Consequently embryos
present in the sites are not as likely to be
subjected to the diversion of O°C water into the
sites.
Downstream of the ice front,staging effects are
expected to be less during the late Stage III
flow regime than the early Stage III flow regime
or other flow regimes and,hence,the embryos
depo~ited in sites within the ice covered reach
...'are·less-Hke·ly-c-to-be affected-by overtopped
conditions.
Ana~ysis of the incubation areas using the
agg~~g~te sp~w~ing habitat response curve for
Representative Groups 2,3 and 4 (Table E.3.2.48
and Figure E.3.2.63)leads to conclusions
similar.to those observed for the modeled sites •
...._.........._..'_'_._..____1'oh!itl.rrabi.t.g..t_jH·.~g.~_il:l_th~th!:~~._R~R~8.~§nl:g..l:tv.8..
__.__._.~__._.______Groups expected to be equalled or exceeded 90
.-----·-percent·;-50 percent .andlOpercent·Ofthelu-
early and late during Stage III operation are
presented in Table E.3.2.1l5 and are depicted in
Figures .E.3.2.116 and E.3.2.117 respectively •
•Effects on Other Evaluation Species/Habitat
.•CQlIlbitja t iO Ill3 ••.(***)
·:1
851021
····fhellabi"t.aEcoiiditions for other evaluation
species/habitat combinations are not expected
to be changed from Stage II as a result of the
initial operation of Stage III of the projec t.
E"'3-2-230
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851021
Hence,the habitat conditions described for
Stages I and II will be maintained into Stage III
operation.
The gradual decline of summer mainstem discharges
and the gradual increase in winter discharges
(Table E.3.2.106)are not expected to affect
overwintering juvenile salmon,salmon embryos or
resident fish species.Hence,the additional
changes to these species/habitat combinations
associated with the flow regime when the project
is operated at maximum capacity are not expected
to be significant.
-Effects of Altered Temperature/Ice Regime (***)
With Watana Reservoir at el.2,185,and as project
energy demands increase and late summer outle t
works releases are reduced,the capacity 0 f the
Project to regulate theLtemperature of the water
released from Watana Reservoir will be increased.
The temperature of water released from Devil Canyon
Dam during early Stage III will be slightly lower
than for Stage II during the July to October period
and slightly higher than for Stage II during the
December to April period.During late Stage III
the Devil Canyon1release temperature will be
slightly warmer than Stage II in June and July,
slightly cooler than Stage II in August and
September,and warmer than for Stage II in December
through April.Release temperatures in late Stage
III will be closer to natural than in Stage II or
early Stage III.
Expected water temperatures at several locations in
the middle river through the summer months are
presented in Table E.3.2.116 and E.3.2.117 for the
natural flow and climate years 1981 and 1982,
respectively.The temperatures presented in these
tables are estimated assuming the flow regime
expected late in Stage III operation.Comparison
of these tables with the similar tables for natural
(Tables E.3.2.83 and E.3.2.84),Stage I (Tables
E.3.2.81 and E.3.2.82),and Stage II (Tables
E.3.2.99 and E.3.2.100)conditions illustrates
that,in general,temperatures are expected\to be
2-3 °c higher than under Stage II operation July
and slightly cooler in the August to October
period.Stage III temperatures are slightly cooler
than Stage I temperatures during the'May through
E-3-2-231
851021
August period and slightly warmer the rest of the
year.During Stage III higher temperatures are
expected to persist somewhat longer in the
September through November time frame than during
Stage I operation.Winter temperatures are
expected to be higher than for either Stage I or II
by about 1 0 c.
The prolongation of warmer water releases in the
fall will,in turn,delay the formation of ice
cover in the winter.Initial ice cover formation
in the middle river is expected to occur 4-6 weeks
later than under natural conditions and 2-3 weeks
later than under Stage II conditions.Simulation
of ice cover formation,progression and recession,
assuming the 1981-1982 winter climate,is presented
in Figure E.3.2.1l8.This simulation is for late
Stage III operation and an average winter.The ice
front was simulated to extend upstream to RM 114.
Depending on cl~matic conditions,the ice front's
maximum upstream extent would be a few miles
upstream or downstream in a cold or warm winter,
respectively (Exhibit E,Chapter 2,Section
4.3.3(c)(ii)).
In conclusion,water temperatures in the mainstem
during operation of late Stage III are expected to
b~higher than Stage II mainstem temperatures in
~June-atid·-Ju-1y--and·cooler-than·Stagerr-inSeptember-
and October.Higher temperatures are expected to
persist longer in the fall during Stage III
operation than during Stage I.Ice cover is
expected to form later in the fall and recede
earlier in the spring under Stage III operation
than under Stage II.Finally,the maximum upstream
progression of the ice front during late Stage III
.()p~:t"~l:.i ()11 ..:i.~..~P~.fJ;~c:LJ;o _Q~..!!Qlllih.ZO_Jlli.1eJL
downstream of the limit expected during__[l:.§l_g_~.II __.
operation •
•Effects on Principal Evaluation Species/Habitat
Combinations (***)
Effects on Juvenile Chinook Rearing
Habitats (***)
--The--expecfea·Iiicreasesin maitist:em water
temperatures from Stage II operation to Stage
III operation are expected to benefit juvenile
chinook salmon inhabiting side channel habitats
E-3-2-232
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851021
(Representative Groups 3 and 4).The warmer
temperatures may promote growth proce&ses of the
juveniles to some extent.However,as discussed
in Section 2.3.1.c.ii,specific conclusions
regarding the effects of altered temperature on
chinook growth cannot be made.
Overall,impacts of the changes in water
temperatures associated with Stage III are
expected to be less severe than those expected
under Stage II and the response of juvenile
chinook rearing is expected to be similar to
that described for Stage I operation.
Similarly,effects on juvenile chinook
overwintering habitats in side sloughs and side
channels (Representative Groups 2 -and 3)are
expected to be similar to those described under
Stage I and Stage II operation.A-major
difference is that overwintering habitats
located downstream from the ice front are not as
likely to be overtopped as under Stage I or
Stage II operation.Estimates of sites in the
middle river expected to be breached during
Stage III operation given the 1981-1982 winter
climate conditions are presented in Table
E.3.2.118.These are compared with the sites
expected to be breached during operation of
Stage II under similar climatic conditions.
Upstream of the ice front,survival of juvenile
chinook during the winter is expected to be
greater than under natural conditions as
described in Section 2.3.I.c.ii.
Effects on Chum Spawning and Incubation
Habitats (***)
The effects of the altered temperature/ice
regime during Stage III of the Susitna
Hydroelectric Project operation are expected to
be similar to those described for Stage I arid
Stage II of project operation.The major
di fference is that chum salmon embryos deposited
in sloughs and side channels upstream of the
expected ice front progression under Stage III
but within the potentially affected reach during
Stage II will be more likely to survive than
under Stages I or II conditions.
E-3-2-233
•Effects on Other Evaluation Species/Habitats
Combination (***)
The changes in water temperature/ice regimes
associated with Stage III of project operation
are expected to affect the other species/habitats
combinations in a manner similar to those
described in Sections 2.3.1.c.ii and 2.3.2.c.ii.
Th.e prolongation of higher water temperatures in
the fall and the reduced progression of the ice
front upstream in the winter will further enhance
the effects described previously for the other
salmon species and resident fish.No additional
effects to upstream migration,spawning and
incubation,rearing and overwintering or
outmigration are expected.
-Effects of Altered Suspended Sediment Regimes (***)
Downstream water releases during Stage III
operations are expected to be less turbid and to
contain less inorganic suspended sediments than
water releases during other project operational
conditions.Total suspended sediment
concentrations and estimated turbidity levels under
Stage III operations are presented in Table
E.3.2.119.,.During the ,open water season of May
through September the middle river mainstem flows
_______________shoulLbe somewhat~ess~turbid_,_andthe_sus_pended
sediment concentrations are expected to be
substantially reduced relative to natural
conditions.During the October through April
season,.however,the project water releases are
expected.to contain greater than natural
concentrations of suspended sediments and turbidity
values.
Thed iieEE ef fecfa-of-p roje-cf-induceda:rter~i"tio-ris--
------of-tlie TS-S-ana---turoi<i-tey----regimes--t-o---j uv-enit-e-"rn-a----
adult fish in the middle river reach are expected
to be stressful,but not lethal during any seasonal
period.Juvenile and adult fish which are
chronically exposed'to turbid mains tem flows are
expected to survive.The indirect effects to the
-fish -communi-ty'of--disturbances of detrital,primary
p:t'gdtlcerand sec:ondaryproducer trophic levels by
.-the----alteredsedimentregime are'presently'uncertain
and unquantifiable.
'j
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851021 E-3-2-234
1
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II
851021
It is anticipated that most salmonid spawning and
incubation subjected to chronically turbid
conditions will be substantially curtailed.
Mainstem and peripheral habitat spawning and
incubation sites not protected by clear upwelling
flows and subjected to chronically turbid mainstem
waters fall into this category.
-Effects of Other Altered Water Quality
Changes (***)
No additional water quality changes attributed to
Stage III operations are anticipated to cause
biologically significant habitat changes within the
middle river reach.
(iii)Talkeetna to Cook Inlet (***)
-Effects of Altered Flow Regime (***)
In general,the flow regime in the lower river
during Stage III Operation is not expected to be
significantly different from the flow regimes
described for Stages I and II.The gradual
increase in winter discharge and decrease in summer
discharge described for the early and late Stage
III flow regimes in the middle river will be
reflected in the respective flows regimes in the
lower river.Summaries of the maximum,mean and
minimum average monthly discharges expected at the
Sunshine Station during early and late Stage III
operation are presented in Table E.3.2.l20.
Summaries for the Susitna Station in the lower
river are presented in Table E.3.2.12l •
•Effects on Principal Evaluation Species/Habitat
Combination (***)
Chinook Rearing Habitats (***)
During Stage III-Operation in the lower river,
chinook rearing habitats will be approximately
the same as that described for Stages I and II.
Habitat areas in side channel and side slough
habitats are expected to be slightly greater
than under natural conditions.Habitat areas in
tributary mouths are expected to be less than
under natural conditions.This is evident from
the comparison of the average discharges at
Sunshine presented in Table E.3.2.120 with the
E-3-2-235
851021
aggregate habitat quality relationships provided
for lower river modeled sites in Figures
E.3.2.83 and E.3.2.84.A summary of the
estimated rearing habitat indices for side
channel side slough complexes under the natural
flow regime and the Stage III flow regimes is
presented in Table E.3.2.l22.Estimated rearing
habitat indices for tributary mouths are also
presented for the natural and Stage III flow
regimes in Table E.3.2.122.
The slightly greater discharges during the
winter months for the late Stage III flow regime
are expected to increase the survival of
juvenile chinook in overwintering areas for the
reasons discussed for the middle river habitats
in Section 2.3.3.c.ii.Hence,no significant
changes to chinook rearing habitats are expected
to occur in the lower river between the Stage II
and Stage III flow regimes.
Chum Spawning/Incubation Habitats (***)
As discussed previously,little chum spawning
activity occurs in habitats influenced by the
lower river mains.tem discharge.Hence,the
changes in habitat conditions associated with
the Stage III operational flow regime are not
-expected to affect chum-spawning popuLations L
•Effects on Other Evaluation Species/Habitat
Combinations (***)
Because the differences in flow regime between
Stage II and Stage III in the lower river are
not great,effects of the Stage III flow regime
to other evaluation/species/habitat combinations
are····not·_·expecTecl-Fo--oe-significant:
-Effects of Altered Temperature/Ice Regime (***)
During operation of Stage III of the project
changes in the temperature and ice regimes from
those expected during Stage II operation are
expected-tobeminimab,-Therefore,the e·ffects on
Evalitation species!hal>itat combination in the lower
-~riverar-enot expected-to··differ from those
expected during Stage II operation.Summer
temperatures are expected to be within the ranges
present under natural conditions principally
E-3-2-236
j.
[)
I ,
[1
I
because of the influence of the Chulitna and
Talkeetna Rivers.Winter ice processes will,
likewise,be similar to those experience during
Stage II.
Overall no additional effects beyond those
described in Sections 2.3.l.c.iii and 2.3.2.c.iii
are expected which are attributable to changes in
water temperature.
-Effects of Altered Suspended Sediment
Regime (***)
Conditions in the lower river during Stage III -
Operations are essentially like those described
for Stage II -Operations (Section 2.3.2.c.iii)
except that the suspended sediment conce~trations
and turbidity values are expected to be lower.
Direct effects on juvenile and adult fish will be
stressful,but not lethal.Lower trophic level
biological activities are expected to be more
productive than during natural conditions during
May through September,but less productive than
during natural conditions from October through
April.The indirect effects of changes in the
temporal regime of biological activities of the
lower troph ic level organisms on the fisheries
popul at ions is unknown..
-Effects of Other Altered Water Quality'
Factors (***)
Stage III -Operational conditions are not expected
to cause major water quality changes other than
those previously discussed which would be of
biological significance to riverine habitats within
the lower river reach.
(iv)Estuary at Cook Inlet (***)
As previously discussed,all project filling and
operational conditions are expected to cause
continuous (i.e.during all seasons)riverine
transport of suspended sediments to the river estuary
at Cook Inlet.Ecological effects on the estuary are
expected to be minimal,as previously discussed in
sections regarding Stage I and II.
851021 E-3-2-237
851021
(d)Summary of Impacts Associated with Stage III
Watana Dam (***)
(i)Construction Impacts (***)
The effects of construction of the Stage III Watana
Dam will be significantly less than those during
Stage I and Stage II,since project roads and the
camps will be constructed prior to the beginning of
this stage.Some transitory impacts,such as
increase in turbidity and sedimentation of local
waterbodies,will occur during the excavation and
movement of the dam fill material.These are not
expected,to have a significant effect on fish
populations.
Increased fishing pressure without specific harvest
regulations will continue to affect local fish
population.
Borrow Site E will create a lake at the expense of
ripariananduplandhabita.t...Rehabilitation measures
will be undertaken to convert this lake into
productive aquatic habitat.
(ii)F.illing (***)
The primary impact associated wi th filling of the
.-.Watanac c~S_tag.e_iILrce_sj~.rxo_Lr:.Lw.il1_Qe__the~ddi.hiQl:l~J
loss of clear water tributory habitat.The
incremental loss of gray ling is ~stimated to be at
least 8,800.The reservoir is not expected to
provide any replacement habitat.
Flows downstream of Devil Canyon Dam will remain
within the CaseE-VI flow .constraints throughout the
fi llingprocess.Wi th increased storage,the
.'capab i Iity-oftliiiFP-foTec~ttoregura:te-d(YwnErEre-am
_..---ftows--wil-1-be--gre-at-ty-in1':r-e-a-sed-;--~-A-s-pro-j-e-ct--energy----·------
production'increasesandoutlet works releases are
reduced water temperatures can be regulated to be
more closely aligned with the natural temperature in
the summernionths.Warmer releases are expected to
persist longer into the fall (September to November)
wicthicecover -··formation occur-ring later and receding
earlier irlthe spring.These conditions are expected
------to--benefit---d-owns tream fisheri-e-s'resourc es.-
E...3-2-238
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]
(iii)Operation (***)
Potential impacts are expected to be similar to those
for operation of the Devil Canyon Dam (see Section
2.3.2.c)and those for filling of Watana reservoir
(see previous Section 2.3.3.b.i).Case E-VI flow
constraints will be followed throughout operation.
Measures implemented in Watana -Stage I will
continue to mitigate for impacts.
2.3.4 -Impacts Associated with Access Roads,Site Roads,and
Railroads (**)
(a)Construction (**)
(i)Construction of Watana Access Road and Auxiliary
Roads (**)
The main access to the Watana damsite will be from
the Denali Highway (APA 1982a).The Watana access_
road will depart the Denali Highway at Milepost 114
and will run 41.6 miles (69.3 km)south to the dam
and campsites (Figures E.3.2.14 and E.3.2.lS).The
northern portion of the route traverses high,
rolling,tundra-covered hills.The road will cross
numerous small streams such as Lily Creek,Seattle
Creek,and Brushkana Creek (Table E.3.2.21).The
northern streams,which are part of the Nenana River
drainage,contain grayling and other resident
species.The southern part of the road will cross
and para~lel Deadman Creek,which also contains
grayling and other resident species.
The gravel road will have a crown width of 24 feet
(7.3 m).Before road construction is begun,a
corridor at least 10 feet (3 m)wide on either side
of the road itself will be cleared.
Short access roads will be needed to reach material
sites and disposal sites.The locations and
alignments of these auxiliary access roads will be
determined when material sites and disposal sites are
identified during final road design.
Prior to access construction,ADOT/PF plans to
upgrade the Denali Highway from Cantwell to Paxson.
Upgrading will include straightening road curves,
improving bridges,and topping the road with more
gravel.
851021 E-3-2-239
851021
Within the project area,the Denali Highway crosses
several small drainages,side channels of the Nenana
River,Edmonds Greek,and Jack River.Jack River
contains grayling and the Nenana River in this region
supports several species of resident fish (Table
E.3.2.56)•
Arty bridge work or straightening associated with road
upgrading will have the potential to cause impacts
similar to those resulting from new construction.
Extension of culverts in pI aces where the road is
widened could affect fish passage.
-Alteration of Water Bodies (**)
Stream crossings can be a cause of adverse impacts.
Bridges and culverts used to cross streams
containing primarily grayling on the main access
road need to be properly sized and bedded to ensure
fish passage.This subjec t is discussed further in
Section 2.4.3.Other causes of adverse road con-
sfructiorii1ll.pactsc8.n result··from the following:
•Clearing (**)
Areas of dense or tall vegetation will have to be
cleared before road building begins.In some
upland areas with tundra vegetation,clearing
-~--w~:ttl-b-e--TIf1n~:tttfa-I-.--Cb:arrng-causes degradation of
habitat when:
o Cleared areas near streams and lakes are not
stabilized alld erode into the water body;
o cleared material is pushed into water bodies
causing blockage of fish movements,deposi-
.tionof .organics on substrates,and
o clearing along streams affects cover,
availability of food organisms,and
temperatures in the stream•
•In-Stream Activity (**)
Q.t!_~JI!g_!c<:>_~d_C:~I!.~_f:E~c:_~:i:.<:>_I!.'_c_it is often necessary
for heavy equipment to enter water bodies.
This can alter the substrate and can cause local
and turbidity sedimentation problems.
E-3-2-240
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851021
•Eros ion (**)
Erosion can result from in-stream use of heavy
equipment,placement of fill with high organic
and/or fines content,lack of stabilization or
revegetation on fills and cuts,and incorrectly
placed or sized cuI verts.The increased
sedimentation that may result can degrade
downstream habitats.
•Fill Placement (**)
Fills that are placed within floodplains and
streams can remove habitat previously used by
fish.The severity of the impact depends upon
the type and amount of habitat covered.
Roads can block sheet flow to or across wetlands.
When a road with insufficient drainage bisects a
wetland,one side becomes ponded while the other
side dries.The change in water quantity affects
the vegetation and the nature of the wetland.
Some wetlands that are contiguous with streams
provide rearing habitat for juvenile fish.If
the w~tlands are dewatered,that habitat can be
reduced or lost.
-Changes in Water Quality (**)
As with dam construction,impacts on water quality
during road cons truct.ion wi 11 resul t mai nly from
erosion and petroleum product spills.Erosion
may occur as the result of excavation for placement
of drainage structures in streams,runoff from
borrow sites,or unstabilized fills,placement of
material within water bodies,and heavy equipment
operating within streams.
Since many of the systems to be crossed by the road
are clear-water grayling streams,they will be
among the habitats more sensitive to increases in
turbidity,sedimentation,and petroleum products.
When equipment is operated in streams or if
refueling of equipment takes place within a
floodplain,petroleum products may enter a
waterbody.Chronic or large spills into these
streams during construction could have severe
effects upon the biota,either ca~sing mortalities
or avoidance of contaminated areas (Maynard and
Weber 1981;Weber et ale 1981).
E-3-2-241
-Disruptions of Fish Populations (**)
Fish.will tend to avoid areas where in-stream work
is being conducted,areas contaminated by petroleum
products or,depending on the circumstance,areas
experiencing excessive turbidity or sedimentation.
Temporary barriers to fish movements and migrations
can be created when streams are diverted,flumed,
or blocked during installation of drainage
structures.Fish can also be prevented from moving
ups tream if drainage structures are incorrec tly
installed.Pumping of water from streams can
adversely affect local populations by entraining
juvenile fish or by reducing localized flows.
During road construction,the area between the
Denali Highway and the Watana damsite·will be
occupied by hundreds of workers.Al though th is
area has been recreationally utilized in past
years,it:~as never experienced such a large influx
of people.This influx could increase fishing
pressure on the streams·and lakes in the area.
(ii)Cons.truction 0 f Devil Canyon Access Road and
Auxiliary Roads (**)
Access to the Devil Canyon damsite will be by road
north of the Susitna River from Watana and by rail
"from··Gold Creek along-the .south-side.of-theSusitna
River.The road will depart from the Watana road
north of the Watana townsite at mile 38.5,and will
parallel Tsusena Creek for approximately 1.5 miles
(2.5 km).The route then roughly follows the
2900-foot (878-m)contour west to Devil Creek.The
road turns south along Devil Creek for about 2 miles
(3 km)and proceeds southwesterly to intersect the
Susitna River at approximately RM 150.The road-crossesthe--ifusTfna..and ·p·ar;illeTs-a:n---unnamecr-creek·
.------.-~.~-~------~~-_.~_.__.~------.----------'---£0 r ----a-sn 0 rt --a-i s tance-;---en,ri ng ---at~flie cons tru c fion--camp-----
and village si teo The road between Watana and Devil
Canyon will be constructed in the same manner as the
segment from the Denali Highway (see Section
2.3.4.a.i)•
.The Devil-Canyon access-road traverses high tundra
th~oughout most of its length.Dense shrub
-veget-ationandtrees areen'counteredwhen the road
nears the Susitna River crossing downstream from
Devil Canyon.The road crosses numerous small
streams between Tsusena and Devil Creeks.A
,J
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l
J
)
1
851021 E-3-2-242
851021
waterfall 3 miles upstream of the confluence of
Tsusena Creek and the Susitna River divide&Tsusena
Creek into an upper and lower watershed.The lower
watershed contains grayling and sculpin,while the
upper watershed contains stunted Dolly Varden and
sculpins.The road crosses Tsusena Creek
approximately 3 miles upstream of the waterfall
(ADF&G 1984a).A waterfall on Devil Creek 1.5 miles
above its mouth presents a barrier to fish
migrations.Grayling are present below this barrier,
while only sculpin were found upstream,in the area
of the road crossing (ADF&G 1984a).Between Devil
Creek and the Susitna River,there appear to be few
areas that provide habitat for fish.The road
between Watanaand Devil Canyon will be constructed
in the same manner as the Denali to Watana segment.
The railroad access will depart from the existing
railroad at Gold Creek and proceed north and east to
the construction campsite (Figure E.3.2.17).It will
remain on the south side of the Susitna River.The
railroad will cross Gold Creek,known to contain
chinook and pink salmon (ADF&G 1983a,1984h,1985b);
Waterfall Creek,known to contain grayling,chinook
salmon,and sculpin in its lower reaches;an unnamed
tributary of Slough 21 that contains chinook fry and
sculpin in its lower reaches;and three tributaries
of Jack Long Creek,which is known to contain
chinook,pink,chum,and coho salmon,rainbow trout,
Arctic grayling,and sculpin (ADF&G 1984h).The
rai lroad parallels Jack Long Creek fo.r approximately
3 miles (5 km)to the railroad terminus and
turnaround at Devil Canyon,adjacent to the upper
reaches of Jack Long Creek.
-Alterations of Water Bodies (**)
Impacts to aquatic habitat can result from stream
crossings and other instream activities.Flood-
plain and side-channel habitat in Devil Creek,
Tsusena Creek,and Jack Long Creek could be
affected by road and railroad aligrnnent.Stream
crossings and drainage structures are discussed in
Section 2.4.l.c.Impacts identified for the Denali
Highway to Watana segment are also applicable to
the Devil Canyon access.
Railroad construction between Devil Canyon and Gold
Creek would have impacts similar to road construc-
E-3-2-243
tion:aquatic habitat could be affected by fills,
clearing,and stream crossings.
-Changes in Water QUality (**)
It is expected that water quality could be affected
by turbidity and petroleum product spills as was
discussed for Watana access.
-Disruptions.of Fish Populations (**)
Fish populations in areas affected by the Devil
Canyon road,auxiliary roads,or the railroad
could experience disruptions similar to those
previously described for Watana access.
(b)Use and Maintenance of Roads (**)
(i)Use and Maintenance of Watana Access Road and
Auxil iary Roads (**)
-Alteration oLWater ,Bodies (**)
Impac ts on water bodies during road operation could
occur as a result of continued maintenance
ac tivi ties .,.Maintenance involves road grading and
replacement of ma·terial.Improper maintenance
techniques can resul t in gravel being pushed 0 ff
the=r9,a"clw'~.y:·illt9 streamJL and~,WE:Lt::lancl,~~t!Q!I1
increased erosion.Road maintenance can have a
greater impact on the smaller streams,such as
Deadman creek,than on the Susitna River.
TIl is section considers only the road section from
the Denali Highway to Watana Dam;therefore,
impacts resulting from road construction will be
confined to streams along this road alignment •
."."'"~",.",,,~-~~,.",,-,,--....,.,.."'''C'~',~",....,'"'''''C'''''''''."..,''•._,,'',,,,,,_'',.__......"__,,,,
During continued road use,changes in water quality
can occur as a result of fuel spills and erosion
from poorly stabilized road surfaces and fill
areas.Large fuel spills would have the greatest
impact on the ,aquatic habitat.
TheWatana"access road will cross numerouss treams ,
some of which contain grayling.In areas where the
roadcrossesorencr.oaches on a waterbody,an
accident involving transport vehicles,including
..)
')
)
,1
I J
)
'.'I
851021 E-3-2-244
1
851021
those carrying petroleum products,could occur.
The impacts associated with spills will depend upon
the season,the type and amount of substance
spilled,the size of the waterbody into Which the
spill occurs,and the fish species present.
Erosion from unstable road cuts could be locally
chronic;however,these activities are not expected
to cause major impacts.The measures planned to
minimize these impacts are discussed in Exhibit E,
Chapter 2,Section 4.4 and 6.11.
-Disturbance of Fish Populations (**)
Fish have been known to avoid areas co~taminated
with petroleum products (Maynard &Weber 1981;
Weber et al.1981)and areas of excessive
sedimentation or turbidity (Iwamoto et al.
1978).Chronic seepage of oil into streams or
lakes could render some areas unusable.
Obstruction of fish passage caused by either
physical or velocity barriers have been discussed
under Section 2.3.4.a.i).
The adverse impacts upon fish populations from the
increased accessibility of fish streams and lakes
to fishing pressure via the network of access
roads could be a greater impact than that resulting
from construction and maintenance of the road
system.As stated in Section 2.3.4.a.i,the Watana
access road will cross Brushkana,Lily,Seattle,.
and Deadman Creeks as well as other small,unnamed
streams.The se creeks are clear-water streams and
many are inhabited by grayling.Deadman Creek,in
particular,is known for its abundant population of
large grayling.The reach of Deadman Creek between
the falls and Deadman Lake is considered prime
grayling habitat.By subjecting this stream to
increased fishing pressure,many of the larger,
older fish will be removed from the population,
altering the age structure and possibly reducing
reproductive potential.A similar impact may occur
to other grayling streams in the area.
(ii)Use and Maintenance of Devil Canyon Access Road,Site
Roads and Railroad (**)
Aquatic habitat and fish populations will be influ-
enced by the existence of roads and railroads
E-3-2-245
through activities such as road traffic and road
maintenance.
-Alteration of Water Bodies (**)
The majority of adverse impacts will have occurred
during road construction.Activities such as
road grading and replacement of drainage structures
could continue to affect stream systems.
-Changes in Water Quality (**)
The impac ts on water qua lity that may occur during
operation of the Watana access road,are also
applicable to the Devil Canyon access road and site
roads.
-Disruptions of Fish Populations (**)
Disruptions of fish populations that could
result from operation of the Devil Canyon access
road-,auxiliary roads,-and railroad are:avoidance
of areas of unacceptable turbidity,sedimentation,
and contamination;blockages of fish passage;and
increased angling pressure.
2.3.5 -Transmission Lines Impacts (**)
(i)Stage I Watana Dam (**)
A detailed description of the Stage I transmission
facilities is presented in Exhibit A,Section 5.
-Alteration of Water Bodies (**)
Adverse-impacts-to water-bodIe-sdurlng con;itrucEIon
--._-~-_.._-of the Stage I transmission II~nes-coul-d-··--result-----··_----_··-
primarily from clearing stream crossings,road
construction,and instream activities associated
with installation of the towers and conductors.
Permanent roads may be built to provide all-season
access.The effects of clearing a right-of-way,
and-heavy-equipmenttrafficonan 'aquatic
environIIlenthave been previouslyd.iscussed in
Secfion-2:3.4.
The transmission system can be divided into four
segments:central (Watana to Gold Creek),Intertie
')
(
r
851021 E-3-2-246
851021
(Willow to Healy),northern (Healy to Ester),and
southern (Willow to Anchorage).In the central
section,,the lines will closely parallel the
Watana-Devil Canyon access road and railroad spur
for much of their length.They will cross Tsusena
Creek,Jack Long Creek and several small tributar-
ies of the Susitna River.The impact of
constructing transmission line through this area
will be similar to,but less than,that of the
access road.See Section 2.3.4 for a description
of river and streams to be crossed in the central
segment.
In the Intertie segment,the lines cross the
Nenana,Talkeetna,Susitna,and Kashwitna Rivers,
Chunila Creek and other smaller streams.The
waterbodies crossed and their fish resources are
described in the Environmental Assessment Report
prepared for the construction of the
Anchorage-Fairbanks Intertie (Commonwea1~h et al.
1982).
In the southern segment,the lines will cross
several Susitna River tributaries,Knik Arm and
Ship Creek.Table E.3.2.57 lists the major streams
to be crossed·and the species that inhabit them.
The streams and fish ~pecies fornthe northern leg
are listed in Table E.3.2.58.
During the transmission line construction,it will
be necessary for heavy equipment such as hydroaxes
and drill rigs to cross streams.Several factors
will influence the severity of impact on the
aquatic habitat.
o Season in which construction takes place;
o Size of the stream;
o Type of habitat in the crossing area;
o Species present;
o Frequency of crossing;
o TYpe of crossing (i.e.temporary bridge,
temporary culvert,low water crossing);
o Streambank configuration;and
o Streambed composition.
It is expected that small,confined streams will be
more susceptible to adverse impacts from transmis-
sion line construction than will larger streams.
E-3-2-247
851021
If "all-weather"access is maintained for the
transmission line,a gravel road would be built
along their entire length and permanent stream
crossings installed,with attendant,long-lasting
impacts.The road and stream crossings would have
to be monitored to ensure that fish passage is
maintained and aquatic habitat is not degraded.
Although the transmission corridor would be many
times longer tha~the access road previously
described,the range of possible impacts is
similar.
The access points for construction of the transmis-
sion lines will be decided during the detailed
design.The Willow to Healy section will probably
use access established during construction of the
Intertie.It is likely that access will require
crossing streams and wetlands.
Details of the installation o,f the cable under
Knik Arm are to be developed during final design.
Knik Arm is primarily a migration rou te for anadro-
mous species that utilize the Knik and Matanuska
River drainages,including five species of Pacific
salmon,Dolly Varden,eulachon,and Bering cisco.
Benthic organisms and other resident species are
sparse because of the excessive amounts of glacial
material on the sea floor.It is unlikely that
instalLation ofth~u_nder_w.~tgJ:'__cablg irt"j;hJ..s ~:rga
will have any effect upon resident or anadromous
species.
-Changes in Water Quality (**)
It is expected that temporary increases in
turbidity and sedimentation will occur in streams
subjected to instream activities during
.--co1:isEruction.'of'Er-ansmiss'i'oiCliuefs:'"'Sman;c Leat"
...,,.·waTer-sy-s-tenn;;-wi-l-l-tn'o's·t--Uke-ly-be---a·ffected-to--a--'·
greater extent than will large systems.The
effects are not expected to be long-term.
In addition,streams that are crossed will be
exposed to possible contamination by petroleum
products due primarily by vehicle accidents.The
measures planned to tninimize the impacts on water
,quality are 'discus'sedin-Exhibit E,Chapter 2,
Sections 4.5 and 6.11.
E-3-2-248
-\
(
.1
I 1
I
l
Disturbance of Fish Populations (**)
Avoidance reactions associated with increased
turbidity and sedimentation may occur.Fish may
also avoid areas where instream activities occur
and,depending upon the timing,migrations could be
affected.Where transmission lines cross a stream,
clearing may remove overhanging vegetation that
provides cover for fish.
Construction of the lines could result in increased
fishing pressure.During construction,this will
most likely be confined to workers.The effects
will be greater in the northern and central seg-
ments where access has previously been limited.
(ii)Stage II Devil Canyon Dam (**)
A detailed description.of the Stage II and Stage III
transmission facilities is presented in Exhibit A,
Sections 10 and 15,respectively.Significant new
impacts are not expected with these additions~since
the majority of the system will be completed during
Stage I (see Exhibit A,Section 5.2.1).
(b)Operation of the Transmission Line (**)
(i)Stage I Watana Dam (**)
Once the transmission lines have been built,there
will be few activities associated with routine
maintenance of towers and lines that could adversely
I
.affect aquatic habitat.However,maintenance of
I all-weather roads would entail efforts similar to
I
i )that for the access road.
-Alteration of Water Bodies (**)
Some localized habitat disruption could occur when
maintenance vehicles need to cross wetlands and
streams to repair damaged lines or towers.Where
roads are not built in conjunction with transmis-
sion lines,some revegetation is allowed to proceed
around the towers.This is usually limited to
grasses,shrubs,and small trees by selective
clearing so that vehicles are able to follow the
cleared area associated with the lines.Streams
may need to be forded in order to effect repairs.
Depending on the season,crossing location,type
and frequency of vehicle traffic,aquatic habitat
851021 E-3-2-249
851021
in the immediate vicinity of the crossing could be
affected.,In addition,downstream reaches may be
affected by increased sedimentation caused by
erosion.
-Changes in Water Quality (**)
Changes in water quality during maintenance of the
transmission lines may result from increased
turbidity and sedimentation,instream activities
and fuel contamination.
-Disturbance of Fish Populations (**)
Instream activities associated with line repair and
maintenance could cause disruptions of fish popu-
lations in limited areas.The greatest disruption
would result from the increased accessibility to
some fishing areas via the cleared transmission
corridor.Because the vegetation would be kept
relatively low ,h ikers and all terrain veh icles
could use the corridorsastrai Is.In winter,snow
machiries would also be able to traverse these
cleared areas.This would result in greater
numbers of fishermen being able to reach areas
previously experiencing little or no fishing
pressure.This effect would be more acute in areas
where the new transmission route diverges from
existing-roads ,',and-e.ransmission-,line s,~---such--as,
south of Willow and north of Healy.The area
between Healy and Willow has been subjected to
disturbance and increased fishing pressure during
construction of the Anchorage/Fairbanks Intertie.
Any increased fishing pressure along the Intertie
as a result of the Susitna lines being added to the
corridor would probably be minor.The presence of
,_"'~__t~aJ:l:.~lll:i l;_1?:iQ1'!~a'\)t~__tJ..!l_ci~_~_l,{tl:i ~AI'1Il sh o_tJ._!ci"cause no
ts to fish ations.
(ii)Stage II Devil Canyon Dam and Stage III
Watana Dam (**)
The addition of lines following construction of
Stage II Devil Canyon Dam and Stage III Watana Dam
is t'iot'expected to result in significant incremental
maintenance impacts over those for S tageI theWliEan:a Dam.-_·_-"_,..0._",--_••_••••
E-3-2-250
,)
"-,'..\
1
I
1
j
2.4 -Mitigation Issues and Mitigating Measures (**)
2.4.1 -Approach to Mitigation (**)
The objective of fisheries mitigation planning for the Susitna
Hydroelectric Project is to provide habitat of sufficient
quality and quantity to maintain natural reproducing populations
where compatible with project objectives.This is consistent
with the mitigation goals of the USFWS and the ADF&G (Table
E.3.!.!).
The priorities for aquatic mitigation,as discussed in Section
1.3 (Figure 3.1.1),were determined by employing the hierarchical
approach to mitigation contained in the Applicant's,USFWS and
ADF&G mitigation policies.The five basic mitigative actions,in
order of priority,are:
o Avoid impacts through design features or schedule
activities to prevent loss of resources.
o Minimize impacts by carefully scheduling and locating
operations,timing and controlling flow releases,and
control impacts through best management practices.
o Rectify impacts by repairing disturbed areas to provide
optional fish habitat and reestablishing fish in repaired
areas.
o Reduce or eliminate impacts over time through monitoring,
maintenance,and proper training of project personnel.
o Compensate for impacts by conducting habitat construction
activities that rehabilitate altered habitat or by managing
resources on project or nearby public lands to increase
habitat values.
Avoidance of impacts to the aquatic environment has been
considered throughout projec t studies.During the initial si te
selection screening process (Exhibit E,Chapter 10),the proposed
project was selected from 91 potential sites as the most
favorable for meeting the future energy requirements for
Southcentral Alaska.One of the key criteria amongst other
environmental,engineering and economic criteria was whether or
not significant anadromous runs existed upstream of the site.
The proposed site scored high because no anadromous fish pass
upstream of the Watana site and only a few (less than 100)p~ss
upstream of the Devil Canyon site.Therefore,the selection
process showed that the location of the proposed site would avoid
many of the potential impacts that would be found at other sites
851021 E-3-2-251
where large numbers of anadromous fish migrate upstream of the
si teo
Avoidance or minimization of impacts were also heavily considered
in the initial design of the dams.The two most prominent
mitigation features incorporated into the dams are fixed cone
valves used to avoid downstream dissolved gas supersaturation and
multi-level intakes which are used to minimize any potential
impacts from an altered water temperature regime.These features
will be incorporated into both dams.Details about them are
provided in Exhibit E,Chapter 2.
Once site selection and initial design features were considered,
the main priority for aquatic mitigation was through flow
regulation.Habitat improvement measures that increase the
productivity of the habitat or provide additional habitat within
the Susitna Basin were the next priority.These measures will be
used for impacts that cannot be mitigated by flow regulation.
Fish propagation facilities would be proposed as compensation,
the least preferred mitigation option.£~
Eachof··the following impactissues·is addressed·in terms of
the five mitigation actions.Table E.3.2.l23 summarizes
mitigation features for major imp~ct issues associated with
operation of the project.
2.4.2 -Selection of Project Evaluation Species (**)
_--c...~~-~~Se'lec·t·ionc'of-·evaluat-ion·spec-iescis-a.cnecessar¥-,--s.tep,in assessing
impacts and in developing mitigation plans.Various species and
life stages have different critical life requirements and
respond differently to habitat alterations.A change in habitat
conditions that benefits one species or life stage may adversely
affect another,and mitigation plans fororie species may conflict
with those proposed for another.Selection of evaluation species
can provide a mechanism to resolve potential conflicts and
.·..Rl:'OYi~t(;!,Q.it:~~t;!9tl..~C?r.a.Il.a.JY~!,~,a.J:l~p!a.t.J:.J:l~J:l~."_.,,"'__..
.···-·--.--~~e eval uation'species were'selec tea---aner 'iniTial---oas'eli-n'e-s'tu-;;;
die sand impact assessments had identified the dominant species
and potential impacts on available habitats throughout the year.
Mitigation plans designed to reduce impacts on habitat parameters
that control populations were then developed.
¥ish~ryres-oul:'cesof'the Susitna River--and -activities-associated
_".!1_i_~~the PE?J~()~_:~_project were reviewed.EV.'lluatiorispecies were
'1
(·1
851021 E-3-2-252 .1
selected on the basis of the following criteria:
o High human use value;
o Dominance in the ecosystem;and
o Sensitivity to project impacts.
Species with high regional visibility and commercial,sport,sub-
sistence,or aesthetic value were given priority.Within this
category,species sensitive to project effects were rated at a
high level of importance.Since the evaluation species playa
dominant role in the ecosystem,they may serve as indicator
species.By maintaining critical habitats for evaluation
species,many of the potential impacts on less sensitive species
or species with a lower evaluation priority will be mitigated.
Five species of Pacific salmon (chum,chinook,coho,sockeye and
pink)were designated as evaluation species for the,S'usitna River
downstream from Devil Canyon.In addition,rainbow trout,burbot
and Dolly Varden were included as evaluation spe~ies.Arctic
grayling was selected as the evaluation species for the
impoundment zone.
Since the greatest changes in downstream habitats are expected in
the reach from Devil Canyon to Talkeetna,fish using that portion
of the river were considered to be the most sensitive to project
effects.Because of the differences in their seasonal habitat
requirements,not all fish species nor life stages would be
equally affected by the proposed project.In the middle river,
chum and sockeye salmon spawning,incubation,and early rearing
in sloughs and juvenile chinook salmon rearing in the mainstem
appear to be most vulnerable because of their dependence on these
habitats.Between chum and sockeye,the former is the most
dominant species in the middle river.
Spawning and incubation life stages for chinook and coho salmon
occur in tributaries.This habitat type will not be affected by
the project.Much of the chinook rearing occurs in tributaries
(again,not affected by the project)and in turbid mainstem side
channels.Coho rearing occurs in tributaries and upland sloughs,
both of which should not be affected.Chum spawning and
incubation occurs in both tributaries and side sloughs.It is
only those that spawn in the sloughs that will be potentially
affected.Sockeye salmon in the middle river only spawn in
sloughs.Spawning in these areas is considered atypical because
this species generally spawns in streams that have nearby access
to a lake for rearing.No such lakes exist in the middle Susitna
River,however,the few sockeye that do spawn in the middle river
are able to utilize upland sloughs for rearing.While some pink
salmon spawn in slough habitats in the middle river,most of
these fish utilize tributary habitats.
851021 E-3-2-253
Mitigationtneasures proposed to maintain chum salmon productivity
will allow sockeye and pink salmon to be maintained as well.
Maintenance of chinook rearing habitat will provide sufficient
habitat for less numerous resident species with similar life
stage req uirements •
The greatest change to resident fish will occur in the impound-
ment zone.In the impoundment zone,Arctic grayling was selected
as the evaluation species because of their abundance in the area,
their sensitivity to impacts during all seasons and life stages,
and their desirability as a sport fish.
Based on the habitat utilization by various li fe stages,certain
evaluation species were given more emphasis in the analysis
because some of these life stages would be directly affected by
the project and this could be critical to their survival.As a
consequence,the evaluation species and life stages,selected for
the Susitna Hydroelectric Project are:
(a)Devil Canyon to Cook Inlet Reach (**)
PRIMARY
Chum Salmon
Spawning adults
-Embryos and pre-emergent fry
Chinook Salmon
-Rearing juveniles
SECONDARY
Chum Salmon
Chinook Salmon
-Returning adults
-Out-migrant juveniles
Sockeye Salmon
-Returning adults
-Spawning adults
}
I,I
J
'\
851021 E-3-2-254
-Embryos and pre-emergent fry
-Rearing juveniles
-Out-migrant juveniles
Coho Salmon
-Returning adults
Rearing juveniles
-Out-migrant juveniles
Pink Salmon
-Returning adults
-Spawning adults
-Embryos and pre-emergent fry
-Out-migrant juveniles
Arc tic Grayling
-Adults
-Juveniles
Rainbow Trout
-Adults
-Juveniles
Dolly Varden
-Adults
Burbot
-Adults
-Juveniles
(b)Impoundment Area (**)
PRIMARY
Arctic Grayling
-Adults
-Juveniles
851021 E-3-2-255
2.4.3 -Mitigation of Cori13ttt:lctibrt Impacts Upon Fish and
Aquatic Habitats (*)
Mitigation of construction impacts is achieved primarily by in-
corporating environmental criteria into pre..,C:onstruction planning
and design,and by good construction practices.Best
Management Practices (BMP)manuals (APA 1985a through 1985e)
and a report on bridge and culvert design (HEl985b)have been
prepared through a coordinated effort involving federal,state
and local government agencies and special interest groups.These
manuals contain environmental guidelines and techniques to be
incorporated into contractual documents prepared for the
construction of the Susitna Hydroelect:dc Project.
The aquatic studies program will continue to make major
contributions to pre-construction planning artd design.Studies
will be used in siting,design and scheduling of project
facilities and activities.For example,the final alignment of
the Watana access road will take into consideration the fish
streams along its route.The route will be sited to avoid
encroachment on streams and to minimize cut banks.
Biological information has been incorporated into the BMP
manuals.A high degree of communication and cooperation will be
maintained between environmental staffs and design and
construction personnel in order to facilitate continued
integration of biological criteria into designs,specifications,
and construction practices.
Monitoring of the construction facilities and activities (as
described in Section 2.6.1)will ensure that impacts to the
aquatic environment are avoided or minimized~Monitoring can
identify areas that may need rehabilitation or maintenance and
areas where previous mitigation measures are proved inadequa te
and remedial action is needed.Costs associated with
construction monitoring are outlined in Table E.3.2.124.
PotentIB::C··Im·piic ts ···are·IdentifIed···In ···sec-':fon2::L ········rhefoTlowitig
.i-sacH seils s ionortlfeimpac t-·iSsue·s-·~fnd-·fne mn:igafion·measures··
that will be applied during and after construction.Those issues
considered to have the greatest potential for adverse impact to
the aquatic environment are discussed first.Avoidance,
minimization,rectification and reduction of impacts are
discussed.There are no direct costs associated with these
mitigations because they will be implemented as part of
construction activities.
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851021 E-3"'2-256 ,1
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851021
(a)Stream Crossings and Encroachments (*)
(i)Impact Issue(*)
Improperly constructed stream crossings can block
fish movements and/or increase siltation in the
stream.Roads with inadequate drainage structure can
alter run-off patterns of nearby wetlands and
streams.Encroachments on stream courses can alter
hydraulic characteristics and increase siltation of
streams,thereby affecting fish habitat.
(ii)Mitigation(*)
The objective of constructing stream crossings is to
maintain the natural stream configuration and flow
(Lauman 1976)so that passage of fish is assured.
Maintenance of fish passage is required under
AS-16 .05.840.-Procedures and guidelines prepared by
the Applicant (APA 1985a)and HE (1985b)will be
utilized to design and construct stream crossings.
Appropriate control measures will be undertaken as
part of routine maintenance to insure that beaver
dams and accumulated debris do not interfere with
fish passage needs.For the project area,the
evaluation species used in developi~g criteria for
stream crossings is Arctic-grayling.
-Presence or Absence of Fish/Fish Habitats (*)
Streams having documented fish or fish habitat at
or upstream from the road crossing will be designed
to pass fish.Only those streams without fish or
fish habitat at,or upstream from,the road
crossing will be designed solely on the basis of
hydrologic and hydraulic criteria.
-Location of Crossing (*)
Project roads will be aligned and located to
minimize the number of stream crossings.When
crossings are unavoidable,they will be located,
whenever possible,at a right angle across the
stream in a straight stretch with narrow,stable
banks that do not require cutting or excessive
stabilization.The crossings will be located so as
to avoid,to the greatest extent prac ticable,
important habitats,such as spawning beds and
overwintering areas.
E-3-2-257
Type of Crossing Structure (*)
Bridges will be utilized wherever streamflows are
large.Open-bottom arch culverts,which maintain
the natural substrates,will be installed
wherever possible (Figure E.3.2.119).Multip1ate
elliptical and oversized circular culverts can also
be used to maintain the natural streambed (Joyce et
a1.1980a;Lauman 1976)and will be used when
open-arch culverts are not feasible.Standard-size
circular culverts will only be used in drainages
that are not considered fish habitat.
During winter transmission line construction,snow
and ice bridges will be used to cross streams.
These will be removed before breakup to avoid
blocking stream flows.
Flow Regime (*)
Culverts will be designed to allow grayling passage
at critical times using the velocity criteria
detailed in the "Drainage Structure and Waterway
Design Guidelines Report"(HE 1985b).Multiplate
elliptical and oversized circular culvert inverts
will be set below the streambed elevation to avoid
perching and will be armored,-when necessary,to
minimize erosion at the outlet.Natural stream
~~~---"--~·~-subst-t'ate-w·i~l-l~be~placed~onthebottomof-the,
culverts over their entire length.
-Methods of Installation (*)
When culverts other than open-bottom arches are
used,streams will be diverted around the work area
until the crossing is completed.On small
systems,thestreammay be flumed.Diversion or
£1 W1i:Fo.g will-reduce ~theamouii-t·o·f sfIEiiEion
downs treamrrom---Ehec ons t ruc tionar ea .-·DTver sian
wi 11 be accompl ished using the procedures detailed
in the BMP Manual entitled "Erosion and
Sedimentation Control "(APA 1985a)and ''D rai nage
Structure and Waterway Design Guidelines"(HE
1985b)and will adhere to ADF&G permit
-..requirementsC
;
-In--sonla-areas·',rOads-ana.'tratismissiotilines must
p'arallel a stream or river.The al ignment will be
away from the floodplain to the greatest extent
feasible.Where this is not possible,the road
-\
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851021 E-3-2-258
)I
(b)
will be aligned to preclude channelization of the
stream.Culverts and drainage structures will be
installed under the fill to maintain the integrity
of the road and the existing water drainage
patterns.
The transmission towers will be spaced and aligned
so that structures are out of streams and flood-
plains to the best extent practicable.Instream
activities will be confined to installation of
drainage structures on access routes using guide-
lines to minimize impacts (APA 1985a,and HE
1985b).Where practicable,construction will be
scheduled for winter months when heavy equipment
can cross frozen creeks without elaborate
constructed crossings.Stream crossings at major
fish streams will be avoided by utilizing secondary
trails from existing roads and railroad corridors.
Increased Fishing Pressure (*)
(i)Impact Issue (*)
The sport fishing pressure on the local streams and
lakes will substantially increase.The access road
and transmission line will allow fishermen to reach
areas that previously received limited use.
(ii)Mitigation (*)
)J
During the construction phase,access to the streams
will be limited by closing roads to unauthorized
project personnel and the general public.Some
watersheds,such as the Deadman Creek/Deadman Lake
system,may req uire modification 0 f current
regulations if stocks are to be maintained.These
changes may take the form of reduced seasons or catch
limits,imposition of maximum size limits,or control
of fishing methods.Since public health regulations
will not allow sport-caught fish to be stored or
prepared at public food service facilities,the
project policy will be that all fishing by project
personnel be restricted to catch-and-release.
(c)Erosion Control (*)
(i)Impac tIssue (*)
Sustained high levels of sediment in a system can
change the species composition and productivity of
851021 E-3-2-259
the system (Bell 1973,Alyeska Pipeline Service
Company 1974).Siltation can affect development of
fish eggs and benthic food organisms.
(ii)Mitigation (*)
The primary mitigation measures that will be used to
minimize construction erosion are detailed in the
BMP Manual entitled "Erosion and Sedimentation
Control"(APA 1985a).
The natural vegetation is a major factor in
preventing erosion (Alyeska Pipeline Service Company
1974).Clearing for roads,transmission lines,and
other facilities will be confined to the minimum area
and level necessary.For transmission lines,only
taller trees and shrubs will be removed;the lower
vegetation will not be disturbed.Adjacent to
streams,especially small.systems,clearing will be
done by hand.Cleared material will be removed from
the floodplain to approved disposal sites,salvaged
or burned ons i te •
Disposal sites that contain cleared slash,sub-
standard materials,and overburden will be located
and configured so that neither run-off during breakup
nor rainfall Mill wash silty material into streams.
This may entail run-off control structures,
sur.rounding.the...dis.posalc.s.ite-w.ith~berms.,.or
channeling run-off through containment ponds.
To preclude run-off from carrying silt to water
bodies near construction sites,drainage control will
direct silty water into settling basins.Clarified
water will be discharged into receiving waters in
accordance with the Alaska Department of
Environmental Conservation (ADEC)permit req':l.!l:'ements-...----(.AS=4'6--:--<fj"":-f"(}(j'·'j-:--------.·..--.--,'.'".---,-,,-'.---,--.','.'---..'-,----._,-------.-----.'.,---,,'.'---.---..--.,.-,.
Prompt grading,mulching,and revegetation of cut-
and-fill areas will also be used to minimize
erosion.
(d)Material Removal (*)
(i)Impact Issue (*)
Removal of floodplain gravel can cause erosion,sil-
tation,increased turbidity,increased ice buildup
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851021 E-3-2-260·1
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851021
caused by ground water overflow,fish entrapment,and
alteration of fish habitat.
(ii)Mitigation (**)
Adverse impacts on aquatic habitats will be avoided
or minimized by application of guidelines contained
in the BMP Manual entitled "Erosion and Sedimentation
Control"(APA 1985a).
Buffer zones will be retained at stream margins.
Instream activities will be restricted to the
installation of stream crossings;material removal
from active channels will not be necessary if the
material quantity and quality at other sites is as
expec ted.
Surface runoff and water used in material washing
will be circulated through sediment settling ponds
and reused in material washing.Runoff control
structures will be installed at borrow sites.
Discharged water will conform to the water quality
standards of the ADEC (18 AAC 70)and the USEPA.
Material will be stuckpiled outside the floodplain or
armored to avoid erosion.Overburden will be stock-
piled for use in borrow site rehabilitation.
Material stored in areas which will be inundated will
be stabilized and covered with riprap prior to
inundation.
The Tsusena Creek material site (Borrow Site E)will
be rehabiliated following the cessation of excavation
activities at the completion of Stage III.Man-made
objects will be removed;exposed slopes will be
contoured and revegetated.The site will be shaped
to enhance fish habitat (Figure E.3.2.l20).This
area will be monitored to ensure that grading,
revegetation and other mitigation measures are
effective.
The Cheechako Creek borrow site (Borrow Site G)will
be inundated by the Devil Canyon reservoir and will
not require rehabilitation beyond that needed to
control erosion.
E-3-2-26l
(e)Oil and Hazardous Material Spills (*)
(i)Impact Issue (*)
Spills of oil and other hazardous substances into
streams can be toxic to fish and their food
organisms.
(ii)Mitigation (*)
A Spill 1?r'evention Contairunent and Countermeasure
Plan (SPCC)will be developed as required by USEPA
(40 CFR 112.7),using the information contained in
the BMP manual entitled "Oil Spill Contingency
Planning"(APA 1985b).
Equipment refueling or repair will not be allowed in
or .near floodplains without adequate provisions to
prevent the escape of petroleum products.Waste oil
will be removed from the site and be disposed of
using ADEC/USEPA-approved procedures.The guideline
and techniques for handling fuel and hazardous wastes
are described in a BMP manual (APA 1985d).Fuel
storage tanks will be located away from waterbodies
and within lined and bermed areas capable of
containing the tank vol ume pI us freeboard fo r precip-
itation.Fuel tanks will be metered and all outflow
of fu~l accounted for.All fuel lines will be loca-
---:--ted-in-abo:v:eground_or~gro.und~surface..ut ilidors to
facilitate location of ruptured or sheared fuel
lines.
Vehicle accidents,although difficult to fully
protect'against,can be minimized by constructing the
roads with properly designed curves to accommodate
winter driving conditions.The roads will be
adequat~ly signed,and during the winter,difficult.......--------.-----.-sEreEches-wiIr~beregurarl.y-cTeared ··ana-sanaed ~-.:ti:i
.'sUIIimer;-aus feo nfr 0 1 wi:n--be-accompl-isned-witli.
water.
State law requires that all spills,no matter how
small,be reported to the ADEC (18AAC70.080).
Personnel.will be assigned to monitor the storage and
transfer of oil and fuel,and to identify and clean
up spilled oil .9.11c1 ()t:h~r_I:t.9.:;::.9.I'c10US material.
All personnel employed on the project,especially
field personnel,will be trained to respond to fuel
spills in accordance with an approved oil spill
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851021 E-3-2-262
contingency plan.The plan will describe:
o Actions to take as a first response in the event
of a fuel spill.
o Persons to contact in the construction
organization and in state agencies.
o Locations of sensitive habitats.
o Location of all oil spill control and cleanup
eq uipment,the type s 0 f eq uipment at each
location and appropriate procedures.
o Records to keep during an oil spill and cleanup
operation.
Oil spill equipment will beprepositioned and ade-
quate to handle the largest spill expected.
Personnel will be trained in the operation of the
equipment,and the equipment will be inventoried and
tested regularly to make sure it is in proper working
order in the event of an emergency.
Impacts from any major oil spill will be assessed in
conjunction with monitoring activities .(see•.S,ection
2.6).Appropriate mitigation measures will be
negotiated in consultation with the involved resource
management agencies.
(f)Water Removal (*)
(i)Impact Issue (*)
Fish fry and juveniles can be impinged on intake
screens or entrained into hoses and pumps when
water is withdrawn from water bodies for
miscellaneous uses during construction.
(ii)Mitigation (*)
Measures to be employed during water removal are
detailed in the BMP manual entitled "Water Supply"
(APA 1985e).
If possible,surface water withdrawal will be from
streams or lakes that do not contain fish.If water
must be withdrawn from a fish-bearing water body,the
Alaska Department of Fish and Game intake design
851021 E-3-2-263
criteria will be incorporate<1into contractual
documents.
The ADF&G criteria are that:(1)all intakes should
be screened;(2)openings in the screen should not
exceed 0.04 sq in;and (3)water velocity at the
screen should not exceed 0.1 ft/sec (0.03 m/sec).No.
more than 20 percent of the instantaneous flow will
be removed at any time.
(g)Blasting (*)
(i)Impact Issue (*)
Blasting in or near fish streams can rupture swim
bladders and damage incubating embryos.
(ii)Mitigation (*)
The ADF&G has standard·blasting guidelines that
establish the distance from water bodies at which
charges can be detonated without harming fish"
Blasting wi 11 be accomplished using these guidelines
(Table E.3.2.l25).
(h)Susitna River Diversions (*)
(i)Impact Issue (*)
The high diversion tunnel velocities and the heavy
bedload of the river make screenirtg of the
diversion tunnels infeasible.Fish passing
downstream through the diversion tunnels are expected
to be lost due to injuries caused by the high
velocities encoctntered in the tunnel.During summer,
relatively few fish are present in the vicinity of
-...-..-.....----...the_t_unne_l_e:gJ:_rJ/'~:Lce_.___Dt,J:~_:i,,!,1gW_:i,I!l;el:',_l:'~1:l~cle~fi.sJ:!_
are expected to be entrained into the diversion._._-~~.intake and~-passed-~downstr·eam.~---'------~.-_._~-~-----------.--.---.---
The Devil Canyon diversion tunnels will act as
barriers to the upstream migration of the few chinook
salmon (less than 100)that spawn in tributary
habitats upstream of this site.
(~:iJ Mi t i gat ion (*)
The segment of the fish population lost in the diver-
sHort turtrtel would be lost -subsequen t to reservoir
filling,because of lost tributary habitat and the
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851021 E-3-2-264
expected low habitat value in the reservoir (see
Section 2.3.1.b).Mitigation for these losses will
be achieved by additional impoundment mitigation
efforts,as discussed under Mitigation for Inundation
Impacts in Section 2.4.4{c).
The loss of chinook habitats above Devil Canyon will
be offset by the increased survival of juvenile
chinook due to the improvement of mainstem and
mains tem-associated habitats downs tream 0 f the dam.
(i)Water Quality Changes (*)
(i)Impact Issue (*)
Discharge of camp effluents result in increased
levels of metals and nutrient loading.Concrete
batching plants release high alkaline effluents.
(ii)Mitigation (*)
Effluents will comply with ADEC/USEPA effluent
standards (AS 46.03.100;18 AAC 70.020;18 AAC
72.010).
The concrete batching effluent will be neutralized
and treated prior to discharge to avoid impacts
r~lated to pH and toxic substances (see Exhibit E,
Chapter 2,Sections 4.1.1{g),4.2.1(g)and 4.3.1{g).
(j)Clearing the Impoundment Area (*)
(i)·Statement of Issue (*)
The major adverse impact associated with removing
vegetation from the impoundment areas is
accelerated erosion into the streams.
(ii)Migitation (*)
Clearing will be scheduled annually as close to
reservoir filling as is feasible.Vegetation will be
cleared to the elevation of the high water level
anticipated for each year of filling.Disturbance to
the vegetated mat will be avoided.Erosion control
me thods described in the BMP manual "Erosion and
Sedimentation Control"(APA 1985a)will be employed
to minimize potential impacts to the aquatic
habitats.
851021 E-3-2-265
2.4.4 -Mitigation of Filling and Operation Impacts (***)
(a)Mitigation of Downstream Impacts Associated with Flow
Regime (***)
(i)Impact Issue (***)
As described in the Exhibit A,the proposed project
would be constructed in three stages.Stage I would
be a dam constructed at the Watana site to an
elevation of 2,025 feet resulting in a full pool
elevation of 2,000 ft.Stage II will add the Devil
Canyon facility.Stage III would raise the full pool
elevation of Stage I at Watana to 2,185 ft.
Even though Case E-VI flow constraints will be in
effect,the actual flow release schedule for initial
filling and opera~ion will vary between each stage.
The reasons for this are the differences in runoff
patterns,storage capabilities~;and energy
requirements.Accordingly,impacts would differ in
magnitude as well as time of occurrence.
One criterion that influences the establishment of
the flow constraints is the choice of the key fish
species and/or life stages to be protected.In the
reach between Talkeetnatzand Devil Canyon,chum salmon
spawning and juvenile chinook salmon rearing were
.giv:enprimar-y_co.ns_ider_ad.o_n_(Sj~cd.Qn 2."4 .21.
As discussed in Section 2.3,a major fishery concern
is the provision of flows between Devil Canyon and
Talkeetna that:
o Allow adult salmon passage into and within
slough and side channel spawning habitat;
···o-·~·.Ma~itifi.fin""·-~a""-·sii-i-fa:Dl-e··---wtft-er----dep'-th-·-""Otf-'-fh-e----"sl)awfiirrg-~-'
···b~eaff ...·th-roll-gh-out-·th-e-·-s·p-awning:per·iod-;----~-~--··-
o Maintain flow through the spawning gravels
during the incu~ation and preemergence period;
o Provide flow of sufficient quantity to allow
the out-mig17ation·of fry;and
o Maintain overwi.nterIng"and summer rearing
habitat for juvenile chinook.
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851021 E-3-2-266
851021
(ii)
Additional fisheries concerns related to instream
flow needs of resident and other juvenile anadromous
fishes include the need to:
o Maintain overwintering and summer rearing
habitat;and
o Maintain access to tributary spawning and
rearing habitat.
The aquisition of additional information on the
relationships between physical processes and habitat
utilization of these two species in the middle river
subsequent to submittal of the original License
Application has permitted addressing these concerns
and has resulted in refinement of the original Case C
flow regime.Eight environmental flow cases were
developed,each designed to achieve specific environ-
mental goals (APA 1984b).These environmental flow
cases can 'be grouped into three broad categories of
which Case C,Case E-V,and Case E-VI are represen-
tative.These three flow regimes were evaluated and
compared in the Fish Mitigation Plan (WCC 1984a).
Case C emphasized providing flows that allowed chum
salmon access into sloughs for spawning.Case E-V
was designed to minimize impacts to both chum salmon
spawning and chinook salmon rearing.Case E-VI,the
Applicant's preferred regime,was designed primarily
to minimize impacts to chinook rearing.
Although the flows under Case E-V minimize impacts to
chum spawning,some habitat modification measures
would still be necessary to rectify the residual
impacts.Furthermore,the effort expended on habitat
modification measures necessary to offset the resi-
dual impacts to spawning habitat under the Case E-VI
regime would not be substantially greater than those
for Case E-V.The primary difference between the two
regimes,therefore,would be the degree to which
impacts to chinook juvenile habitat are minimized or
avoided.The hierarchical approach to mitigation
option analysis that follows considers flow release
schedules for each stage of development with Case
E-VI constraints in effect.
Measures to Avoid Impacts (***)
Adverse impacts to fishery resources resulting from
flow alteration will be avoided or minimized through
selection of an appropriate flow regime.While
E-3-2-267
hydroelectric developments with storage facilities
al ter the na tural flow regime in the river,.changes
in streamflow patterns do not necessarily result in
adverse impacts to fish populations.For example,if
low flows ara limiting fish populations,then supple-
menting low flow may result in enhancement to that
population.However,under the proposed flow regimes
for filling and each stage of development,passage
into sloughs by adult salmon may be impaired and
mitigation measures in addition to flow regulation
are needed to reduce these impacts.
(iii)Measures to Minimize Impacts (***)
The Case E-VI flow constraints are designed to
ml.nl.ml.ze impacts to Juvenile chinook rearing.Loss
of spawning habitat for chum salmon,however,would
not be minimized by Case E-VI flows.The minimum
discharge constraint for Case E-VI is greater than
natural flows in the winter months and less than ICo
natural discharges in the summer months.
-Winter Flow Regime (October-April)(***)
Stage I -Filling (1998)(***)
851021
Filling of Watana reservoir is scheduled to occur
in the first spring-summer runoff period.
---c--During-the--first~winter-foHowingHH-ing,.
November 1998 to March 1999,the reservoir level
would be held constant or reduced as energy is
produced so that releases would equal or exceed
inflow.Since no impacts are anticipated,
mitigation measures are not proposed •
•Stage I ~.Operation (1999)(***)
--._---,.~..._~-_._-..-.-....••..•.'.".-._-.....,._.".._..".__.._-.'_..~"._._..__._-"",,,'._--.'.,.--.-.'.'._.-",.-.',,_....-.'.,-_....-._-.
Winter flows during the first year of operation
-would range from approxlmatefy-7 ,OOO-toI0~(ro-O-------
cfs.As the winter ice cover forms,the staging
associated wi th the higher than natural flows
would resul t in increased upwelling benefitting
incubation but might also result in near -a°c
mainstem water overtopping some sloughs and
possibly retarding·the growth and delaying the
emergence of.embryos tha tordinarily incubate at
2"';3°C~This ups-fream prOgressioti of the ice
front and potential for overtopping would extend
to RM 139 in anaverge year and would be a few
miles upstream or downstream of this in a cold or
E-3-2-268
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851021
average year,respectively.Mitigation measures
would be necessary for those sloughs with a high
likelihood of overtopping •
•Stage II and III -Filling and Operation (***)
Case E-VI flow constraints will continue to be
followed.Since measures to mitigate impacts
are based on these constraints and were in place
during Stage I,no additional measures would be
necessary.
-Spring Flow Regime (May-June)(***)
With-project,the ice cover is expected to
substantially melt in place rather than break-up as
under natural conditions.During the May-June
period flows would be reduced under project flow
regimes.Project flows of sufficient quantity
would be provided to allow sa1mo~.fry to outmigrate
from natal sloughs and,side channels.
-Summer Flow Regime (Ju1y~September)(***)
•Stage I -Filling (1998)(***)
Summer flow release levels during July and August
would depend on the ~ydro1ogic conditions of that
year.September flows.would be within Case
E-VI flow constraints.Under dry conditions,
flow releases in July and August would be at the
Case E-VI dry year minimum of 8,000 cfs.In an
average year,July and August flows would be
about 12,000 cfs and 13,000 cfs,respectively,
somewhat higher than E-VI minimum (9,000 cfs)yet
reduced from average natural flows of 24,000 cfs
and 22,000 cfs.In a wet year,flow releases
would increase to 15,000 cfs and 20,000 cfs,
closer to the average natural condition.
Chum salmon enter spawning areas during the
summer.Most of the spawning in the Devil Canyon
to Talkeetna reach is confined to sloughs and
tributaries.Access to slough spawning areas is
apparently provided by a combination of high
summer flows in the Susitna River mains tern and
local surface inflow.Flow into the sloughs is
at least partly controlled by water levels
in the mains tern.Upwelling ground water in the
sloughs attracts adults,maintains the
E-3-2-269
permeability of spawning gravels,and provides a
stable winter flow and temperature during the
embryo'incubatidn per iod.
Detailed analyses of mainstem flows required for
successful passage into the major chum salmon
spawning sloughs have been conducted by ADF&G
(1984r).However,a quantitative assessment of
the availability of successful passage
conditions during reservoir filling using this
information is not possible for average and wet
years since the available flow data,mean monthly
:flows,mask the monthly variability caused by
short-term rainstorm events that often provide
passage.It can be assumed,however,
that since the mean monthly flows for fi lling are
less than those for natural years in August and
September for average and wet years that the
frequency 0 f success ful .passage'condi tions may be
reduced.In a dry year,with Case E-VI minimum
flows during the spawning period,and assuming no
local runoff (no variability around the minimum
:E:\.owvalue).,passage would be possible at only
two passage reaches of the seven sites evaluated
-one in Slough 8A and one in Side Channel 21.
Additional mitigation measures would be necessary
to offset these·impacts.
Stage I summer flows would be less than natural,
although the flows are substantially greater than
E-VI minimum constraints during the chum salmon
spawning seasOn (August 12 -September 12).A
reduction in the frequency of occurren~e of
successful passage conditions and availability of
suitable habitat would occur.The extent of.--.__._.._--_._-------._...-.,..•_~..---....'""..--_...-.'.---_._-------_._-,,_.....--~_.,._._--"._---,---.'-..-"-'.'.'--_•..._--_.-_._........,-.-_._..
these reductions for the major chum producing
"'sloughs and side 'channels-rS[o-ughs 8A~9~"9A;IT~
21 and Upper Side Channel 11 and Side Channel 21)
were analyzed'.The results are found in the
mitigation plan (WCC 1984a).Mitigation measures
in addition to flow regulation would be necessary
to reduce the impa.cts •
•Stages I and II -Filling and Operation (**)
Case E-VI flow constraints will continue to be
followed.Since measures to mitigate for
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851021 E':'3-2-270
r)
851021
impacts are based on these constraints and were
in place during Stage I,no additional measures
would be necessary.
(iv)Rectification of Impacts (**)
-Winter Flows (**)
Impacts to chum salmon embryos resulting from
overtopping of sloughs and side channels during
the winter will be rectified by construction of
berms at the head of the slough.
The ice staging with Stage I flow will require
construction of berms such as those described in
the Fish Mitigation Plan (WCC 1984a).Details of
the length,height,location and cost"of berming
that may be necessary for passage are being
discussed through consultation with the respective
resource agencies.Habitat modification measures
proposed for spawning (summer flows)are also being
discussed.Cost estimates for berms only at the
head of sloughs range from $24,000 to $161,000.
-Spring Flows (**)
If it is shown through monitoring (Section 2.6)
that salmon fry require a high flow at breakup in
order to stimulate out-migration,a properly timed
pulse of sufficient magnitude may be provided.
-Summer Flows (**)
Impacts to salmon spawning areas will occur if
mitigation measures are not employed in coordina-
tion with the proposed project flows (or the
alternative regime of short-term augmented flows).
The rectification methods selected are (1)to
maintain access to the sloughs;and (2)to ensure
suitable spawning and incubation habitat by physi-
cally modifying the sloughs,to maximize use of
reduced filling and operational summer flows.The
following habitat enhancement measures will be
applied either singly or in combination on sloughs,
depending on the type of impacts that limits salmon
production.These methods will maintain salmon
productivity in the sloughs.
E-3-2-271
851021
•Slough Excavation (**)
Mechanical excavation of certain reaches of
sloughs will be used to improve fish passage and
fish habitat within the sloughs.At slough
mouths,excavation will provide fish access when
backwater levels are negligible during low
mainstem discharges.Mechanical excavation will
be used to facilitate passage within sloughs by
channelizing the flow or deepening the thalweg
profile at the passage reach.
On a larger scale,mechanical excavation to lower
the profile of the entire slough is expected to
increase the amount of upwelling.Increasing the
difference in water level between ithe mainstem
and the habitat area would result in additional
local flow in the slough.
An additional benefit of the excavation process
would be the opportunity to improve the substrate
in the slough.Replacement of exis ting substrate
with suitable spawning gravels would provide
additional spawning habitat.Sorting of the
existing substrate will be undertaken to remove
unsuitable particle sizes.The excavation
process would be designed to develop additional
spawning and rearing habitat.
An estimate of the cost to excavate a typical
slough mouth in the middle portion of the Susitna
River is $26,000.An estimate of the cost to
lower a typical slough profi Ie by 2 feet fo r a
length of 2,000 feet in the middle section of the
Susitna River is $34,000.
FISh ac-cess~l:hroughpass~ige-reacheswiTI·be·
improved by creating a series of pools.Barriers
will be placed to break the flow on long,steep
passage reachs and create pools between
obstacles.Fish passage over the obstacles is
accomplished if sufficient steps of decreased
barrier heights .g.reprovided to permit
surmounting the~original barrier (Bell 1973).
Channel barriers will be used on long slopes to
create fish resting pools,as shown in Figure
E.3.2.l21).'lhese barriers,with heights of 10
E-3-2-272
1
I,1
,J
to 14 inches,act as weirs.They have a section
of decreased height to improve fish passage
between pools.The barriers are constructed of
various materials.Concrete,cobbles,or
boulders placed to create a sill may be used.
Logs or gabions may also be attached to the banks
and anchored securely to the bed to prevent
movement at high discharges (Lister et ale
1980).
Channels will be constrained in width to form
effective pools.For a wide channel,channel
widths will be modified where a pool and weir
structure is desired.
Estimates of costs per barrier on the basis of a
two barrier sys tem are lis ted below.Each slope
will require more than one barrier to create a
series of pools.As more barriers are built on a
site,the cost per barrier will decrease because
of the economics of scale;the major cost
involved in the construction of the barrier is
the cost of transporting equipment.
11
\ J
Barrier
Concre te sill
Rock sill
Gabions
Anchored logs available on site
Anchored logs not available on site
•Channel Width Modifications (**)
Cost/Barrier
$12,000
16,000
12,000
11 ,000
12,000
851021
Channeling slough flow will improve fish access
through passage reaches by constricting the width
and increasing the depth of the channel.This
is especially useful in modifying short,wide
passage reaches (Figure E.3.2.l22.Wing
deflectors extending out from the channel bank or
rock gabions restructuring the cross section of
the natural channel may be used to constrict the
flow width (Bell 1973).
In determining the modified width for the
channel,a maximum velocity criteria of 8 fps
will be used to permit fish access through the
reach (Bell 1973).
E-3-2-273
•Wing Deflectors (**)
Wing deflectors will be used to divert the flow
in a channel.TWo wing deflectors placed on
opposite banks will funnel the flow from a
wider to a narrower cross section as shown in
Figure E.3.2.l22.The narrowed channel is
designed to provide fish passage at a minimum
flow.At higher flows,the wing deflectors are
inundated;fill between the banks and the wing
deflector walls is sized to prevent scouring at
higher discharges.Fill will typically be
composed of large cobbles available at the
sloughs.
Wing deflector walls will be constructed either
of rock or gabions formed of wire mesh and filled
with cobbles.Another alternative is the use of
l2-inch-diameter timbers,anchored to the banks
and channel bed."~A wing deflector cos ts $31,000
when constructed of rock,approximately $24,000
when constructed with gabions,arid $22,000 if
timber logs available on site are used.For
sites where timber is not available,a log wing
deflector would cost $23,000.Estimates are
based on a typical passage reach of approximately
200 feet for a slough on the Middle Susitna River
(Figur~E.3.2.l22)•
•Rock Gabion Channel (**)
Reshaping the original cross section of the
channeLwi,thrpck.gabions is an alternative
method of channelizing the slough flow.The
channel is excavated and gabions are used to
establish the new configuration.The new channel
-.sha pe.-isdesigned.to.maximi zedepth a tm inimum
.......f.Lo.-W..s..;_a_t...higber discharges ,.the_gabionSRreVetlt _
scouring of the channel banks.Figure E.3.2.122
i llus trates a typical cross sec tion for a
reshaped passage reach.For long passage
reaches,resting areas are created by widening
the channel between the rock gab ions forming the
minimum discharge channel.The gabions are
proviciecithroughout the length of the passage
'reac:h~aIld.protec:ted upstream byripra.p or ~ing
wall gabions.The gabion banks extend higher
than the height of the maximum slough discharge
to prevent collapse from erosion.
1
,J
851021 E-3-2-274
r
!I
851021
The gabions composing the channel banks prevent
scouring of the banks;the channel wilt be more
stable than a similar channel modified by wing
deflectors.For passage reaches with greatly
varying discharges,the added stability of the
rock gabion channel is an advantage.The cost of
constructing the gabion channel is approximately
$60,000 for a typical passage reach 200 feet in
length •
•Prevention of Slough Overtopping (**)
Project flows are higher than natural discharges
in the winter.Ice staging at these discharges
can result in an increase in mainstem stage and
increase the probability of overtopping of
sloughs downstream of the ice cover'front.
An influx of cold mainstem water into the habitat
used for incubation in the Slough 8A in 1982
caused adverse impacts (ADF&G 1983e).To prevent
overtopping,the height of the slough berms will
be increased as shown in Figure E.3.2.l23.
Cost estimates per berm range from $24,000 to
$161,000 or higher depending on the slough head
configurations and the anticipated mainstem
stage •
•Gated Water Supply System (**)
In the absence of large flows in sloughs and side
channels,debris buildup,siltation,and algae
growth may create passage restrictions and
decrease available spawning habitat.Side
sloughs and side channels are breached under
natural conditions with a recurrence frequency
from 1 to 4 years.The large breaching flows
remove obstacles and scour the channel bed.
Flows of 50 cfs or greater may be required for
the removal of debris and channel scouring.
Under project conditions,breaching of the
sloughs and side channels will occur less
frequently in spring and summer months and may
not provide sufficient flushing of the channel.
A gated pipeline extending under the berm at the
head of a slough or side channel could provide
large quantities of flow during unbreached
cond i tions.
E-3-2-275
851021
The gated water supply system consists of a
corrugated pipe with a gate valve structure.The
pipe intake is protected by a riprap cover to
prevent the entrainment of fish and debris.The
riprap will stabilize the bank of the berm at the
intake by preventing scour.Large riprap at the
outlet will create turbulent conditions for
improved air entrainment and the dissipation of
energy to prevent excessive channel bed erosion.
The gate valve structure will enable the manual
opening of'the pipe to.allow large flows into the
channel.In order to provide the required flow,
the pipe system will be operated at a high
mainstem discharge.To prevent the influx of
turbid water during chum spawning or
near-freezing water during incubation,the pipe
gate valve will remain closed during the fall and
winter months.
The water supply system will be designed to',
provide as much flow as necessary to maintain the
substrate in Clea.ricoriditio11 a.nd to prevent scour
of spawning gravels.The pipe diameter and
length will depend on the hydraulic~~onditions in
the ma.instem and slough.The estimated cost of a
system with 3-foot ~iameter pipe and a 2,500 foot
length is $100,000.
Asecofcrtteriahasbeendevetoped to establish
a means.of ranking sloughs for modification on a
benefit-cost basis.The criteria applied to each
slough include the relat ive utilization,the
frequency of overtopping,the extent of berming
required to prevent overtopping,and the location
and extent of passage reach modifications.The
use of these criteria in a decision making flow
....chartis.presented.in Figure.E .J.2.12.4.A~....
______..inl:tic_aJ:~_d3n_the_char.!;.,..5!..slough with higher
relative utilization,low probabilit-yof wInter··
overtoppin.g,and minor passage reach modification
requirements will receive the highest ranking.
As information on the extent of berming necessary
for each site is acquired,this set of criteria
will be applied to each of the major chum salmon
pr odtl.cing sloughs •
..",..,-,,,......•_-,,,..,..,..,.,.,,,.,,.,..•-,',
If the cost of modifying one or more of these
sloughs is excessive,alternative sites will be
evaluated for modification as replacement
habitat.A sufficient number of sites will be
E-3-2-276
,..1
851021
modified to insure there is no net loss of
habitat value.
(v)Reduction of Impacts Over Time (0)
A monitoring program will be conducted to evaluate
the effectiveness of mitigation measures (see
Section 2.6).
(vi)Compensation for Impacts (**)
It is anticipated that flow-related impacts will be
adequately reduced with the preceeding mitigation
measures.However,if for some reason they do not
work,the Applicant will compensate for the lost
fishery resources.The goal of this compensation
will be to produce the number of fry expected to be
lost from the impacted area.
A technique for incubating-chum salmon eggs current ly
in use in British Columbia referred to as an incuba-
tion chamber is proposed.The subsurface incubation
chamber consists of a wooden box 10 x 20 x 5 ft deep
set to a depth of '3 feet below the lowest water table
elevation.A slotted wood floor installed in the
bottom of the box approximately 6 inches above the
base intercepts the groundwater flow.
The incubation chamber can accommodate a monolayer of
500,000 eggs and requires a flow rate of approxi-
mately 50 gpm.The advantages of the incubation
chamber over the traditional egg incubation box
include:1)a wide range of potential sites for
installation,2)direct installation in a slough
eliminating the need to construct rearing ponds,3)a
constant reliable water source somewhat independent
of weather conditions,and 4)access to the same
source of upwelling groundwater that surrounds
naturally incubating embryos.
It is estimated that one or two of these incubation
chambers would replace all of the chum salmon that
might be impacted by the proposed project.The total
cost for these chambers would be from $50,000 to
$70,000.Al though th is is the leas t preferred
mitigation option,it is the least costly.The
reason that this option is not proposed is that it
includes artificial propagation which is the
Applicant's third priority mitigation option.
E-3-2-277
(b)Mitigation of Downstream Impacts Associated with Altered
Water Temperature Regime (*)
(i)Impact Issue (*)
The creation of Watana and Devil Canyon Reservoirs
will change the downstream temperature regime of
the Susitna River.Reservoirs act as heat sinks,
reducing the annual variability and the rate of
change in water temperatures by moderating summer and
winter temperatures and introducing a time lag.The
magnitude of change in the thermal regime downstream
depends on the thermal stratification of the
reservoir and the design of the power intake and
release structures.
Some seasonal stratification is expected to occur in
Watana Reservoir.(See Exhibit E,Chapter 2,Section
4.1.3(c)(i)).The water temperatures downstream from
the dam are set in part by the elevation of the
intake structures,which in turn determine the
temperature 0 f the water drawn from the reservoir.
Since growth rate of many aquatic organisms is
temperature-dependent,changes in the thermal regime
can affect aquatic communities.Potential adverse
effects of higher winter temperatures include
acceleration of incubation and early emergence of
salmonid embryos and benthic invertebrates.The
------imp ac-f:Of-,-tbwer~summer~temper-a:tures~i:n-ctt:n:le-s.slow er
growth of invertebrates,juvenile anadromous,and
resident fish.Changes in the thermal character and
its effects will decrease downstream as tributaries
contribute to the flow and as the temperature regime
approaches an equilibrium state.The impacts related
to the thermal changes are expected to be confined to
the Talkeetna to Devil Canyon reach.
u~(iil.__Measures to Avoid ImRacts~(~L__
The only mitigative alternative that would completely
avoid temperature changes downstream from the
project is the no project alternative.Hydroelectric
projects involving reservoir storage dams will alter
the natural temperature regimes.
-(iii)Measures c to·Minimize.Impac ts (*)
The impacts associated with alteration of the temper-
ature regime during reservoir operation will be
851021 E-3-2-278
minimized by incorporating multiple-level gates in
the power intake.Multiple level intakes nave
successfully regulated temperature of downstream
releases (Nelson et ale 1978).
The success of temperature regulation depends on the
thermal structure of the reservoir and the location
of the intake ports.A reservoir operation model was
used in the design of the multi-level intake
structure.Results of the modelling show that the
multi-level intake will maintain downstream water
tempera tures wi th in acceptable limits.Detai Is 0 f
the modelling are provided in Exhibit E,Chapter 2.
The cost of providing multi-level intake structure
for temperature control is provided in Table
E.3.2.126.
(c)Mitigation of Inundation Impacts on Mainstem and Tributary
Habitats (**)
[j
851021
(i)
(ii)
Impact Issue (**)
The Arctic grayling population in the impoundment
area of both reservoirs was estimated to be ,~
approximately 20,000 grayling greater than 8 inches
(20 cm)(Tables E.3.2-.127"artd E.3.2.l28).This
population uses the clearwater tributaries as
spawning and rearing habitat and the tributaries and
Susitna River mainstem as overwintering habitat.A
major project impact will be the loss of grayling
spawning .and rearing habitat in the inundated portion
of the tributaries.Some grayling that will be
displaced from inundated tributary habitats are
expected to utilize habitats in tributaries above the
impoundment water levels or in the impoundment near
tributary mouths.Although fishery resources are
expected to exist at some level of productivity,for
planning purposes,the Applicant is assuming that
all existing grayling habitat in the reaches of
clearwater tributaries to be inundated will be lost.
Although the Stage I Watana impoundment will affect
somewhat less area,the Stage III Watana impoundment
will ultimately inundate the same area described in
the original License Application.
Measures to Avoid Impacts (0)
The only mitigation alternative that will avoid im-
poundment impacts for the proposed project is the
no project alternative.
E-3-2-279
(iii)Measures to Minimize Impac ts (*)
Mitigation measures that would substantially m~n~m~ze
impoundment impacts to fish populations would be to
substantially lower the surface elevation of the
reservoir or to maintain water levels during the
grayling spawning and incubation period (May through
June).Neither measure is economically feasible.
(iv)Measures to Rectify Impacts (*)
Since the impoundment is essentially a permanent
impact,rectification measures are not feasible.
Rec tifying measures,such as providing replacement
grayling spawning habitat within the impoundment are
not considered feasible because of the timing and
magnitude of the drawdown cycle.
(v)Reduction of Impacts (0)
Impacts cannot be reduced over time since no effec-
tive mitigation measures have been identified.
(vi)Compensation for Impacts (***)
Measures to compensate for the loss of grayling
habitat are the only feasible options proposed for
impoundment mitigation planning.Compensation
---------------------~meastires --havebeen-"re-f-ined---to re-fl-e-c-t---Ehe Alaska
Department of Fish and Game's preferred measures of
compensation.In a letter to the Applicant dated 31
December 1984,the Department indicated that
acquisi tion of public access to the Susitna River and
its eastside tributaries below Talkeetna and the
enhancement of spawning habitat for salmon are
preferred mitigation measures.Compensation by
.-.----propagacingand stocking rainbow trout-is not
..pr-efer.red..-Therefore.,..impoundment.mitigat.ion-options.....
to compensate for lost grayling habitat include:
o acquisition of public access to the lower
Susitna River and its eastside tributaries;
and
o improvement of habitat for selected salmon and
resident fish stocks:in the middle and lower
river reaches.
851021 E-3-2-280
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851021
Acquisition of public access to the lower Susitna
River or its eastside tributaries would provide
additional recreational opportunities in the basin as
public access to the Susitna River below the Parks
Highway bridge (RM 84)is presently limited to a
private boat launch at Kashwitna (RM 61)and some
eastside tributaries along the George Parks Highway.
The Alaska Department of Fish and Game has proposed
the acquisition process as a mitigation measure to
offset impoundment area impacts.The Applicant
considers the acquisition of public access a feasible
option and will evaluate site selections in coordina-
tion with resource agencies.A recreational plan
prepared in late 1984 by the State of Alaska
recommends the acquisition of several land parcels in
the Susitna Basin t.o insure public access to present
and future fishing areas (Alaska Department of
Natural Resources 1985).This recreational plan and
any subsequent planning documents on public access in
the Susitna Basin will be used in the site selection
process.
Habitat improvements for selected salmon and resident
fish in the middle and lower reaches of the Susitna
River have the potential to compensate for lost
habitat in the impoundment area.Such enhancement - -
could include opening presentlyunutilized areas to
access by fish or modifying sloughs in the middle
river to improve rearing or overwintering conditions
for juvenile salmon and resident fish.The Applicant
plans to evaluate potential habitat improvement sites
in further detail.
The propagation and stocking of Arctic grayling is
not a proposed measure to compensate for lost habitat
in the impoundments at this time.The agencies have
noted that hatchery production of grayling finger-
lings is presently in the developmental stage and
cannot be fully relied on to provide compensation.
Reasons for this position have been:(1)the lack of
reliable egg sources;(2)low survival from the green
egg to fry stage;(3)unsuccessful attempts to rear
grayling fry to fingerling in hatcheries;and (4)the
inability to evaluate survival of stocked fry because
of their small size.However,the Applicant has .
continued to evaluate this option because of the
desireability of in-kind compensation.Moreover,
recent studies at Clear Hatchery,Alaska,suggest
that large scale fingerling production 0 f grayling is
feasible.Fingerling production at Clear Hatchery
E-3-2-281
apparently hinges on the rearing of fry to.the
fingerling stage with acceptable survival rates,as
egg sources and incubation technology are adequate
and appear to be somewhat secure in the future (Parks
et aL 1985).In 1984,over 100,000 two-gram
fingerling were produced at Clear Hatchery with an
average fry-to-fingerling survival rate of 22 percent
(Parks et al.1985).However,in feeding
experiments that tested various kinds of commercial
feeds,the.survival ra te exceeded 70 percent'for fish
fed a diet of krill.This success would appear to
make artificial propagation and stocking of Arctic
grayling a viable option for compensation.
Since compensation for lost grayling habitat is the
primary concern in impoundment mitigation planning,
the cos ts developed in the original License
Application for propagating and stocking grayling can
be used as a bas is to budge t for the acq ui sit ion 0 f
public access and habitat improvements.The costs
associated with public access acquisitions and
habitat improvements are presented in Table
E.3.2.126.
(d)Mitigation of Downstream Impacts Associated with Nitrogen
Supersaturation (0)
(i)Impact Issue (0)
I J
,\
·1
'1
Nitrogen supersaturation in outflow waters has caused 'J
significant fish mortalities from gas bubble disease.'
Water passing over a high spillway into a deep
plunge pool entrains air.Nitrogen passes into
solution at depth and 'a state of supersaturation
exists when the water returns to the,surface.The
degree to which this occurs depends on the depth of
..................-,.......----.the ··plunge-pool .,heightof the-spiHway.,amount'of·
.......~.__~-__water beirtg-s.pU..led.,.-and downs.trc-eam.··tu·r'bulence·.·····,.,~--.
Supersaturated water is unstable and eventually will
return to equil ibrium levels if exposed to the air.i l
However,travel time downstream during high flow I,I
periods can be fairly short,causing supersaturation
to extend considerable distances downstream.
~._....
(ii)Measures to Avoid Impacts (0)
Gas supersaturation will be avoided by including
fixed-cone valves in the outlet facilities.These
valves,in combination with flood storage pools at
851021 E-3-2-282
)
1
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(iii)
Watana and Devil Canyon Dams and the powerhouse
flows,will discharge all flood flows up to·the
1:50-year flood without causing supersaturation to
exceed naturally occurring levels.A discussion of
the effectiveness of the cone valves is in Exhibit E,
Chapter 2,Se~tion 6.4.4.Costs associated with
providing the gas supersaturation control structures
are provided in Table E.3.2.126.
Measures to Minimize Impacts (0)
The likelihood of creating gas supersaturation down-
stream from the dam will be further minimized·
through reservoir management.Releases occur when
the reservoir is full and inflow exceeds releases
required for power and instream flow requirements.
The reservoir must reach maximum storage level by
September 30 to meet winter power demands.Storms do
occur in the Susitna drainage that may require
release of water;however,the structures and
operation criteria have been designed to minimize
releases and spills.
2.4.5 -Cumulative Effectiveness of Mitigations (0)
(a)Construction Mitigation (0)
Through siting and design of project facilities,appropriate
construction practices,and careful scheduling of
activities as discussed in Section 2.4.3,adverse impacts to
aquatic habitats resulting from project construction will be
avoided or minimized.The indirect impacts caused by
increased access to harvestable fish populations will be
reduced during construction by instituting a catch-
and-release policy for project workers,and by supporting
such harvest regulations as the Alaska Board of Fisheries
imposes.It is expected that impacts will not be totally
avoided and that increased access will have long-term
impacts on fish populations caused by the increased harvest
pressure.
Aquatic habitat will be altered by removing gravel from the
floodplain.These impacts will be rectified by rehabilita-
tion practices discussed in Section 2.4.3.
Fuel spills and road runoff may decrease water quality in
streams downhill from project roads.These impacts will be
reduced by having a properly trained and equipped spill
response team at the construction site.
851021 E-3-2-283
Monitoring during construciton (see Section 2.6.1)will
verify that environmentally acceptable construction
practices,as defined by the bid specifications,required
permits and the BMPmanua1~are being followed.Monitoring
will be conducted during project construction to recommend
changes in construction practices or mitigation features·to
further avoid,minimize,or reduce impacts.
(b)Operation Mitigation (**)
(i)Mitigations of Access and Impoundment Impacts (**)
Road access to the project area will result in in-
crease resource use.Angling pressure will be
controlled by the Board of Fisheries through"
fisheries management techniques,perhaps including
catch limits,restrictive capture techniques (e.g.,
fly fishing only and single hook),and adjustments in
the open season.
The loss of clearwater tributary habitats in the
impoundment zones'wiTl becolIlpensated by the
following mitigation measures:(1)acquisition of
pul:>l ic access to the lower Sus'rtna River and its
eastside tributaries;and (2)enhancement of habitat
for selected ~a1mon and resident species in the
middle and lower Susitna River reaches.Mitigation
measures offsetting the expected losses for the Stage
.--~..c"='~'==--r~'n--aiiCf=ttt~deveropments=wiTt=De"=impremenfed,'dtlring
the Stage I measures because the greatest impacts in
the project area are expected with the initial
development.
The acquisition of public access to the lower Susitna
River and its eastisde tributaries will provide
additional fishing opportunities in the basin and
wi-ll help even out resource utilization.Habitat
_.impxo:v:ements __that...enhance":':impor.tant._s.p,or.t_species_o£,,_
salmon (chinook and coho)or important resident
species (rainbow trout and Arctic grayling)would
offset expected habitat losses in the impoundment
zones.Sites will be selected after field
evaluations of potential sites are done.
(ii)Mitigation of Downstream Impacts (*)
The goal of the downstream mitigation program is to
provide adequate habitat downstream from Devil Canyon
Dam that will minimize adverse impaCts on fish
,l
:I
,I
'I
\\)
1
851021 E-3-2-284
resources.It is anticipated that the mitigation
program will fully maintain,and probably enhance,
salmon productivity in the Devil Canyon to Talkeetna
reach.Essentially all proposed mitigation measures
for downstream impacts will be implemented with Stage
I Watana,primarily because the mitigation measures
needed for this stage will be sufficient for Stages
II and III.To assure that the measures meet their
intended purpose,a monitoring plan will be
implemented (see Section 2.6).
Several project features have been incorporated into
the design of the project to avoid or reduce impacts.
Fixed-cone valves will be installed in the outlet
facilities to minimize the potential for gas
supersaturation to exceed naturally occurring levels.
The multiple-level power intake gates will allow
water to be withdrawn from the upper levels of the =-
water column over the full drawdown range.This
ability to withdr~w water from the upper levels will
allow control over downstream temperatures to remain
within acceptable levels.
The Case E--VI flow constraints will alter the
hydraulic characteristics of the sloughs,thereby
reducing ease 0 f access and available spawning area
for adult salmon and increasing embryo mortality if
the sloughs dewater or freeze after spawning is
completed.
The project operational flows will allow downstream
impacts to be minimized when used in conjunction with
proposed rectifying and compensating measures (wee
1984a).The primary rectifying measure is to use
stream enhancement techniques to modify natural
slough habitats to maintain natural salmon spawning
and fry production.The slough enhancement process
is composed of a series of steps to rectify the loss
of natural slough habitat.These steps may be used
singly or in combination in any particular area,
depending on the controlling factors in an affected
slough.These steps are (wee 1984a):
o Provide an upstream berm that will prevent the
river from entering the enhanced slough
during winter staging.This control maintains
the integrity of the spawning gravels and
reduces thermal impacts.
851021 E-3-2-285
o Select a slough that retains ground water flow
with suitable thermal characteristics'under
operational flow levels.The selection process
is evaluating a number 0 f criteria to assess
the potential for the slough to maintain
sufficient ground water flow under operational
flows to maintain salmon embryos through the
winter and allow properly timed development.
Emphasis will be on sloughs that are currently
most productive.
o Provide adult salmon with access into the
slough by enhancing the backwater effect at the
slough mouth and lowering the slough profile.
o If ground water flow cannot be naturally
maintained by lowering the slough'profile,
areas where the ground water flow can be
artificially maintained will be considered.
The extent and type of habitat enhancement depends on~
natural site cha.racteristics ,"such as ground water
flow rates,size of natural features,and factors
that appear to limit salmon productivity in each
slough.The number of sloughs modified will depend
on the desired level of production.It is the
Applicant's intent to maintain production at
historical levels.
2.5 -Aquatic Studies Program (**)
Aquatic studies are an integral part of the continuing planning and
design for the Susitna Hydroelectric Project.The information
presented in this document is based primarily on results of the 1981
through 1984 studies.The mitigation plan (wee 1984a)has been refined
based on these studies and analyses.
__TJJft-_em~hasis for~he .C!quatic studies prog~am~as shi~~~~~oward
developing design criteria needed to implement the mitigatfon fea-tures-
and to baseline monitoring (see Section 2.6).These studies,described
in the following sec tion,can be divided into precons truction,
construction,filling,and operational phases of the project.
2.5.1 -preconstuction Phase (**)
..During the preconstruction.phase,..the aquatic studies program
will:
o Provide supplemental information required for pre-project
baseline monitoring;
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851021 E-3-2-286
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o Refine the proposed mitigation measures.
The need for specific tasks will be translated into study
programs.
2.5.2 -Construction Phase (*)
During the planning for construction,information will be needed
to properly design site facilities and schedule construction
activites to avoid impacts to aquatic habitats.Incorporating
environmental design criteria into design,siting,and scheduling
activities is a major feature of the construction mitigation
plan.Review of proposed actions and facilities will generate
the need for some additional data and information.These needs
will be incorporated into the study program.Environmental
design criteria will be incorporatad during the planning stage in
order to avoid or minimize impacts.
2.5.3 -Filling and Operation Phases (0)
During filling and operation,monitoring studies,as discussed
below,will permit refinement of mitigation features to improve
performance.
2.6 -Monitoring Studies (**)
As discussed in Sec tion 1.3,monitoring studies are recognized as an
essential project mitigation feature that provides for a reduction of
impacts over time.Monitoring will be conducted during project
construction and operation:
o To insure that good construction practices are being employed on
the project;
o To evaluate the effectiveness of the operation and maintenance of
mitigation features;and
o To recommend changes in construction practices or mitigation
features to further avoid,minimize,or reduce impacts.
Aquatic monitoring for this project is divided into two broad
ca te gorie s:
o Construction monitoring and regulatory compliance
o Long-term monitoring
Construction monitoring will be extensively involved in assuring that
the licensing and permitting stipulations for construction activities
are carried out.Long-term monitoring will be conducted primarily to:
851021 E-3-2-287
o Evaluate impact projections
o Assess levels of resource production to ensure that these levels
are maintained
o Evaluate the effectiveness of project mitigation measures for
area$downstream of the project and within the impoundment zones
o Provide input needed to refine operation and mitigation measures
o Provide supplemental baseline information
During the development of the dams,there will be considerable overlap
of pre-project,construction,and operational periods..Due to this
overlap,some construction monitoring and long-term monitoring will
occur concurrently.(F.or example,fish monitoring will be needed for
both categories of monitoring but because it is believed that such
monitoring will be needed for a period of time after construction is
comple te,fish monitoring is grouped into long-term monitoring.)Even
though this overlap will exist,construction monitoring and long-term
monitoring will be considered separate categories for monitoring.
2.6.1 -Construction Monitoring (***)
Construction monitoring activities will co.verall project
facilities,including access road construction and maintenance,
transmission line construction,camp and village construction,
material removal,material washing operations,reservoir-nearing";-~ana rel"ia1fiTn:ai:icfif-neeaecrauefo··cons t rucfTorC-~
activities.Monitoring will be done to ensure that proper
construction practices are being followed and that project
facilities are being properly maintained.
The Applicant has prepared five Best Management Practices (BMP)
manuals (APA 1985a,1985 b,1985c,1985d,1985e)to be used in the
design,construction and maintenance of the Applicant's
o Oil Spill Contingency Planning
o Erosion and Sedimentation Control
o Liquid and Solid Waste
o Fuel and Hazardous Materials
o Water Supply
These manuals are the result of a coordinated effort involving
:Fl:'cl e:r.al,st:.ate.al1clloc.aLgoYl:':r11llll:'Ilt:.agl:'l1ciel:l:,.al1cl-ot:l1er group£;~
The manuals are compendiums of typical practices that can be used
to avoid or minimize environmental impacts from construction,
operation,and maintenance of the Applicant's energy projects.
In addition,a report entitled ''Drainage Structure and Waterway
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851021 E-3-2-288
Design Guidelines"(HE 1985b)has been prepared for the specific
purpose of assuring that culverts and bridges are designed to
meet the Alaska Department of Fish and Game's proposed
regulations for these structures.
The BMP manuals will be provided to the design engineer,who will
utilize them in the preparation of both design and construction
documents.The Applicant intends that guidelines contained in
these Best Management Practice manuals be incorporated where
appropriate into the contractual documents of the project.In
this way,they become an integral part of the contract
requirements for construction activities.
construction monitoring will be implemented to ensure that proper
construction practices,as detailed in the BMP manuals and
Drainage Structure and.Waterway Design Guidelines,are being
followed and that project facilities are being properly
maintained.
It is anticipated that environmental concerns and regulations
during construction will be addressed through a continuing
process of consultation between the Applicant and the resource
agencies.This process has been ongoing since the Applicant
initiated project-related studies.Agencies have already been
involved in the review of the BMP manuals and Drainage Structure
Guidelines,initial design of project features (as presented in
feasibility reports and the original License Application),and
other project documents.It is anticipated that this process
will continue through the design,construction,and operation
periods.
The Applicant will continue its practice of regular consultation
with individual agencies and.other project participants.The
Applicant envisions that these meetings will be held at least
once every two months and will be the forum in which participants
will be apprised of the current status of the work.These
meetings will also provide for interactive discussions with the
Applicant and its design contractors.
During the design process,specific features will be described in
detail.For each major project feature (e.g.dam,spillway,
camp,etc),design memoranda will be developed based on the
criteria and plans presented in this License Application
Amendment.In areas where environm~ntal concerns may be
involved,these memoranda will be distributed to resource
agencies for review and comment.Prior to construction,the
agencies will also review the final design and means of
construction with regard to permits,permit stipulations,and
design and construction criteria.This will ensure conformance
to approved practices.
851021 E-3-2-289
construction of the main access road will begin in April 1990.
From that time until all stages of the project are complete,
construction monitoring will occur.To build the project,the
Applicant will hire a firm that will manage construction.This
firm will hire contractors needed to build the project.To
provide overall onsite responsibility for the Applicant,~here
will be a resident manager,at the site;for the construction
manager there will be a resident engineer.One of the main
responsibilities of the resident manager will be to assure
adherence to requirements of the FERC license and other agency
permits and regulations.This will be implemented through the
resident manager.
Mitigation measures for construction will be part of contractual
documents and will be adhered to just the same as any other
contrac tual requirement (e .g.,safety>procedures required by
OSHA).By incorporating the environmental concerns'in the
contract documents,the Federal,state,and local ageneies can be
assured that these concerns will be enforced in the field.In
order that environmental and regulatory concerns receive the same
level'of attention as is being devoted to other phases of project
---development;theApplicanthajf fOrmed thepositiot'FOf-Director of
Environment and Licensing (DEL).The DEL has the same stature as
the Dire-ctor of Engineering,Director of Construction,and the
Director of Administration.All of the aforementioned directors,
as well as the Susitna Project Manager,are responsible to the
Associate Executive Director of Projects.
CC-CCC-~Ks~the~ons-tteYepnrsent-ative--of~th-e~-DEL~;--th-e-.Appcticaireintends to
have at least one member of its staff designated as an
Environmental Field Officer (EFO).The EFO will be required to
be thoroughly familiar with plans and specincations ,as well as
the special regulatory permit stipulations and general
environmental statutes and regulations.It will be the EFO's
responsibility to enforce those portions of the'construction
contract documents that incorporate the environmental
....stipulati onss p ecified in_the permit s.and __license_._
The EFO will directly interface with the Applicant's resident
engineer and the cons truction manager.The onsi te
construction manager will be thoroughly familiar with the
regulatory requirements and plans and specifications.These
quality control assurance personnel will give equal weight to
technical and environmental concerns in carrying out their field
itispec tiollres ponsibi liiies :The-EFO -through tJieDEL--wi 11 be the
-Applicant'sJie!cl'!ic':ii~,?_n .w~th .:r~sourcelreg':l!at'?ry agencies.
The Applicant is committed to working with an interagency review
team and will support its effort by providing data,analysis and
technical support.The resource agencies may,at their own
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851021 E--3-2-290
discretion and funding,have an observer onsite to assure
themselves that agency interests are maintained.The Applicant
will provide this observer with field support as needed.It will
be the responsibility of the resource agencies to select this
observer.If the observer sees a problem,he can relate this
directly to the EFO,the agency concerned,or the FERC.Whether
or not the resource agencies desire an onsite observer,the DEL
will contact the appropriate agencies prior to the contractor
beginning a major work item,in order that the agency may have
the opportunity to request a site inspection.
The EFO will have a staff that assists him in assuring that
environmental requirements of the contracts are carried out.If
a violation of the contract occurs (such as principles of the BMP
Manuals are not being followed),the EFO will take action by
notifying the appropriate person in the constru~tion manager's
organization.If no response occurs,the EFO will notify the DEL
and the resident manager.The resident manager,in turn,will
notify the construction manager to take corrective action.It is
envisioned that this entire procedure will require only a short
period of time (minutes).Depending on the incident,the
appropriate resource agency will also be notified.
Once construction has begun,onsite changes in permit
stipulations may be required because of changes in construction
techniques or unforeseen problems that are not included in
contracts.If a variance is required,the agency observer onsite
should have the authority to authorize field actions that were
not specified in the permits.It is strongly suggested that the
observer have this authority because offsite decisions would
require time and potential costly delays.After facilities or
portions of facilities have been constructed,the EFO will review
the designs and ver{fy that the facility is in compliance with
contracts,permits,and license stipulations.
If a facility or activity is found not to be in compliance with
existing stipulations and if a variance was not requested prior
to implementing the activity,a certificate of non-compliance
will be issued and all responsible parties will be notified.
The construction schedule and proximity of activities will
dictate the size of the EFO's staff.During Stage I Watana
construction the staff will be large since activities will
include construction of the access road and,soon after,the
Watana dam.
This level will be high through Stage II Devil Canyon completion.
During the Stage III Watana Dam construction,EFO staff and the
extent of their coverage will be reduced since most activities
will be limited to the damsite.As indicated by the current
851021 E-3-2-291
schedule,construction activities,including the construction
monitoring program,will end in 2012.
The Applicant believes that the above procedures are a prudent
approach since both the Applicant and the resource agencies will
need flexibility to resolve the day-to-day implementation of
monitoring plans in an expeditious and cost effective manner.
Regardless of.how many contingency plans are developed,some of
the field problems that occur during implementation are typically
resolved as they occur.Therefore,some procedural flexibility
is necessary in order to develop workable solutions.
2.6.2 -Long-term Monitoring (***)
Long-term monitoring will focus on areas downstream of the
project and in the impoundment zones.The purposes of this
plan will be to:
o Evaluate the effectiveness of mitigation measures
o Provide input to refine operation and mitigation measures
o Provide supplemental baseline information
The.general approach to long-term monitoring will be to monitor
selected na·tura1'eonditions for a number of years (in some cases,
monitoring for natural conditions is complete).The length of
time needed and the data requirements will depend on the
-pat:'ame·ter-oE--s·ituat-ion-tobe -monit oE-ed.~.Cond·it-ions·-w-i~1-1···then be
monitored after Stage I Watana Dam construction begins and will
continue through project completion.The natural and
with-project information wi 11 then be compared to determine if
significant impacts have occurred and to determine the
effectiveness of mitigation measures.The parameters that will
be monitored will only be tho se that are considered good
indicators of change (for the sy stem)and are readily measured
....................__..and anal ts associated with 1 term monitoritlg~re
Tab1eE..2.29.
Project planning is separated into the following time periods:
o Existing conditions
o Stage I Watana Dam
a.Construction of Stage I Watana Dam
.b.Operation
o Stage II Devil Canyon Dam
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851021 E-3-2-292
851021
a.Construction of Devil Canyon Dam and operation of Stage
I Watana Dam
b.Operation of Devil Canyon and Stage I Watana Dams
o Stage III Watana Dam
a.Construction of Stage III Watana Dam and operation of
Devil Canyon Dam
b.Operation of Stage III Watana and Devil Canyon Dams
Long term monitoring of the aquatic environment in each of these
periods is necessary.Prior to initiation of project
construction,existing conditions will be monitored to establish
baseline conditions.For the Susitna Project,a major portion of
this baseline monitoring has already been accomplished,primarily
since.1980,when field studies were initiated by the Applicant.
Once construction begins,monitoring of the other periods will be
necessary to de termine if pre-project projections are correc.t and
to assure that mitigation measures are successful in achieving
their intended goals O'!r.
During project development,there will be considerable overlap of
pre-projec t,cons truction,and operat ional periods.Due to this
overlap,some ,construction monitoring (Section 2.5)and long-term
monitoring will occur concurrently.For example,fish monitoring
will be needed for both categories of monitoring but because it
is believed t~at such monitoring will be needed for a period of
time after construction is complete,fish monitoring is grouped
into long-term monitoring.
The plan outlined in this section will begin with the 1985 field
season (Table E.3.2.l30).This will not preclude the possible·
analysis and use of previously collected data.The plan will
continue through project construction with some of the studies
continuing into project operation.
The with-project monitoring schedule will depend on the specific
parameters to be monitored and the degree of preC1S10n necessary
to determine if project-induced changes have been detected at an
acceptable level.
The long-term monitoring plan encompasses the entire project
period and not anyone stage.The reason for this is that once
construction begins,the environment of the project area will be
altered.This will then continue through all construction phases
and into operation.This plan should not be considered
unchangeable however,because studies will be refined through
consultation with resource agencies,both individually and in the
interagency group forum.Likewise,the effectiveness of
mitigation measures will be determined through monitoring.
E-3-2-293
Should mitigation measures require modification,the resource
agencies as a group,or individually,will be consul ted·and
agreement will be reached on specific modifications.
During construction and initial project operation,the Applicant
will,on an annual basis,submit a report on aquatic monitoring
to the FERC and resource agencies for review and comment.This
repo~t will describe the results of monitoring for the year and
provide an analysis of whether or not mitigation measures are
achieving their purposes.The need for continued monitoring will
be reviewed periodically.It is envisioned that as the project
matures,any significant impacts will be fully mitigated and the
need for field studies/monitoring will decrease,i.e.,portions
of the aquatic monitoring program will be terminated when the
need for further mitigation is considered unnecessa~.
Consequently,the need for reports on an annuaL.basis may also
decrease.
2.6.3 -Long-term Monitoring Elements (***)
Af3ar~sul~ofstudJ~sL analyses,alld .ggellcyconsultation,
specific elements of project development and operation that
will need long-term monitoring were identified.These monitoring
elements include:
o Water qua lity upstream and dowtfstream of the project
incl uding:
1.Dissolved Gas Supersaturat
2.Temperature/Ice
3.Turbidity
4.Mercury/Heavy Metals
o Critical fish Ii fe history stages including:
1.Adult salmon
·······2;-Eggincubation,·juvenile·-rearing',-and·outmigration
·3.-Res·ident-·f-ish··----._--.--.---.----.---..--------.
o Fluvial geomorphology
o Structural alteration of habitat,suchas slough
modifications
---The plans proposed for long term monitoring are primarily
·co-riceinea W:i-:-thareas~downsfreamo f thepro)'e·ctarea ~···A
monitoring plan will.be developed to evaluate the efficacy of the
proposed,impoundm~p.tarea mitigation program.This will be done
following finalization of mitigation plans for this area.
)
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851021 E-3-2-294
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The following sections provide additional details on the scope
and activities associated with the various monitoring elements.
(a)Dissolved Gas Supersaturation (***)
Dissolved gas supersaturation from dams primarily occurs
when water is released over a spillway and plunges into a
pool.This entrains air and carries it to depth where the
hydrostatic head forces it into solution.If the
hydrostatic head at depth is sufficient,the air will stay
in solution.At shallower depths,however,supersaturated
gas comes out of solution as the gases equilibrate with the
atmosphere,thus causing bubbles to form.If the gas comes
out of solution within a fish,it may cause mortality,or
sublethal stress.
To avoid potential impacts from supersaturation (and
minimize the need to spill water over the spillway),the
Project will provided means for storing and releasing all
floods with recurrence intervals of 50 yeats or less without
the need for using spillway discharges.One of the means
will be to provide fixed cone valves for both dams (all
project stages).Releases from these valves would be
dispersed as a spray and,therefore would not plunge to
depth nor be expected to cause gas saturations in excess of
110 percent downstream.
Six cone valves are planned for Watana Dam (same valves for
both Stages).These valves will "have a 24,000 cubic feet
per second (cfs)discharge capacity (maximum).Devil Canyon
will have seven cone valves with a 38,500 cfs discharge
capacity.
Natural turbulence in Devil Canyon causes supersaturation,
with higher discharges resulting in higher dissolved gas
concentrations (Figure E.3.2.125).These concentrations can
exceed the State of Alaska maximum allowable standard of 110
percent total gas saturation when flows in the river are
greater than about 15,000 to 20,000 cfs.Naturally
occurring gas supersaturation levels decrease by
approximately 50 percent in the first 20 miles downstream of
Devil Canyon.Fish collected in the area of highest:gas
concentrations have not exhibited any of the signs
associated with bubble disease (ADF&G 1983n).
The data collected thus far is sufficient to provide a
general understanding of the relationships concerning
dissolved gas concentrations in the Devils Canyon reach.
Additional pre-project data will be needed to provide a more
complete record of baseline conditions.
851021 E-3-2-295
The primary purpose of this portion of the monitoring plan
will be to evaluate cone valve operation in order to assure
that significant impacts due to gas supersaturation do not
occur.
The main objectives of the dissolved gas saturation monitor-
ing wi 11 be to:
o Document the relationship between flows and natural
dissolved gas concentrations
o
o
Monitor fixed-cone valve operation to de termine if
with-project dissolved gas concentrations agree with
projections
Evaluate the effects of~spillway discharges on I 1
dissolved gas concentrations.
To comple te the evaluation of the fixed-cone valve
operation,the following sourc:esof information wi 11 be
utilized:
o Baseline data on dissolved gas concentrations
previously collected on the Susitna River by the
ADF&G
o Additional pre-project monitoring of dissolved gas
concentrations
o Data from monitoring of dissolved gas concentrations
during testing of the cone valves and spillways at
both Watana and Devil Canyon Dams
Monitoring to complete baseline data collection will occur
during the 1985 field sampling season (Table E.3.2.l30).
With-project monitoring will occur when each stage of the
project i-s·complete (i..•.------_-_..-_.---
(b)Tempera.ture/lce (***)
The Watana (Stages I and III)and Devil Canyon Reservoirs
will cause temperatures in the river downstream from the
dams to differ from natural conditions (see Exhibit E,
Chapter 2,Section 4.0).Water temperatures in the spring
are expec·fed to be below naturalbyafe,w degrees Celsius
<cJ..Inmid...summer,.theyw.i11benear.naturaL In the
fall,water temperatures will be above natural by a few
degrees C.In the winter,due to releases of water ranging
from 0 to 4°C from the reservoir,a large portion of the
river downstream of the dams will remain free of ice.When
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851021 E-3-2-296
851021
the three stages are complete,the open water is estimated
to be about 15 to 35 miles downstream from the dam.In this
ice-free area,temperatures may remain above natural (O°C)
by up to 3°C throughout the winter.The variation from
natural will be greatest near the dam,and will decrease
with distance downstream.Under the ice cover,temperatures
will be O°C,the same as for natural conditions
(AEIDC 1984c).
During the winter,warmer releases will cause the ice front
progression up the middle reach to be delayed by 2'to 6
weeks.Higher than natural winte~discharges will result in
elevated water levels downstream of the ice front.Upstream
of the with-project ice front,water levels will be lower
than natural because natural staging due to the ice cover
will be eliminated.
Changes from natural conditions will result in the more
frequent overtoppings of slough berms wherever an ice cover
forms.This overtopping will introduce cold (O°C)~ater and
ice into the sloughs.Plans to prevent this overtopping
include increasing the height of the berms at the upper ends
of the sloughs (wec 1984a).The Applicant has included
mul ti-level intakes in the designs for both ·,the Watana (both
low and high phases)and Devil Canyon developments to
mitigate for these potential temperature impac ts.These
intakes will be operated to provide as near natural
t~mperatures as possible.
The purposes for monitoring water temperature and ice will
be to:
o Determine the range of temperatures experienced in the
Susitna under natural conditions
o Monitor with-project temperatures
o If necessary,refine multi-level intake and cone valve
operation after actual with-project conditions have
been observed
o Monitor with-project ice conditions
o Monitor occurrences of ice-induced slough overtopping
with-project conditions
The main objective will be to determine if the water
temperatures and ice conditions downstream of the projects
agree with pre-project projections.
E-3-2-297
The primary sources of data will be:
o Temperature c!tnd ice data already collected by the
Applicant at various locations throughout the Susitna
Basin
o Additional pre-project data
o Data collected when the dams begin filling and
operating
(c)Turbidity/Sediment (***)
During the ice-covered season,the natural turbidity and
suspended sediment concentrations of the Susitna River are
near zero.During much of the open water season,the river
is highly turbid and carries large volumes of suspended
sedimerits.Open water suspended sediments average
approximately 700 mg/l (HE 1984c).Peak turbidity values
may be as high as several thousand nephelometric turbidity
unit's (NTU's)•
Most sediments tha t presently depend on the river's tractive
force fOT downstream transport are expected to be trapped
upstream of the dams.Particles passing downstream through
the dams will be fewer and smaller,and the average mineral
composition and three-dimensional shapes will be altered.
The present suspended sediment and turbidity regimes should
oec6memore seaso~ra.rty cotl.titl.uousand-l·esTvariaDle~
Enhancement of biological productivity is possible if
sufficiently clearer water can be combined with river
temperatures and a flow regime which protects critical
aquatic habitats during appropriate seasons.
Biological changes are expected to occur at all trophic
levels iri aquatic habitats directly affected by
pt"oject-induced.changesinsuspended--sediment-andturbidity...
--------.---.__.__..____r_eginies_.Bec_aus.e chang~ts.__in_th.e_s.e_lta r ame_t.er s can .e i ther
positively or negatively affect fishery resources,it is
important to understand how much change will occur.
The purpose for monitoring turbidity and suspended sediment
concentrations under existing and wi th-projec t conditions
will be to determine whether or not<changes in these
parame ters sIgni.fi.c::antIy affect Hshery resource s d.ownstream
():ft:.hep'~()ject~S~gtlif~ca.tlt:.C!l1Il()unts of~tlf()rmati()t1 have
already been recorded concerning baseline turbidity and
suspended sediment levels (HE 1984c).
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851021 E-3-2-298
'T
The main objectives of these studies will be to:
o Determine if with-project conditions agree with
pre-project predictions
o Determine the seasonal changes in turbidity and
suspended sediments that occur due to the project
o To the extent possible,determine how these changes
have affected the fishery resources downstream of the
project
One year of pre-project monitoring will be needed to
establish a better record and understanding of natural
conditions.Most efforts will be applied to the open water
season.Another year will be necessary when Watana (Stage
I)begins operation and at least one additional year when
Devil Canyon and Watana (Stage III)begin operation.
Monitoring of turbidity and suspended sediments will likely
be required as part of the construction monitoring program .)0
and during reservoir filling.Therefore,it is expected
that this program will be almost continuous from the start
of construction through early operation of both dams.
(d)Heavy Metal Concentrations in Fish (***)
A number of metals naturally exist in the·Susitna River at
detectable levels.The most biologically significant of
these metals are mercury,copper,cadmium,and zinc.
Post-impoundment water quality studies in existing
reservoirs have shown that only one of these metals,mercury
(Hg),systematically bioaccumulates to relatively high
concentrations in fish tissue as a direct result of
impoundment (Bodaly et ale 1984,Meister et ale 1979).
These concentrations in fish tissue might exceed (greater
than 0.5 mg-mercury/mg of fi~h tissue)those that are
considered safe for human consumption.After impoundment,
microbial methylation of mercury associated with the organic
matter in soils and newly inundated detritus of the project
reservoirs may result in higher than natural mercury
concentrations in reservoir fish.Several environmental
factors in the project reservoirs will tend to minimize
mercury biomethylation and subsequent concentration in the
tissues of fish and higher trophic level organisms such as
man and vertebrate predators:
o Low year-round water temperature
o Low rates of benthic microbiological activity
851021 E-3-2-299
o Blanketing of inundated organic matter with a layer of
inorganic sediments
o Relatively limited fish populations
Although information exists on mercury concentrations in
fish in impoundment areas,no comparable information exists
on mercury concentrations in fish downstream of dams,at
least not directly related to a dam.If concentration of
mercury potentially occurs in fish downstream of the
project,resident fish,in contrast to anadromous species,
might be more affected by freshwater mercury concentration
because anadromous species (such as salmon)will acquire
most of their mercury tissue burden from the marine
environment and will therefore be relatively less affected
by the project.
Cadmium,in contrast to mercury,is not present in high
concentrations in the Susitna River.Thus,it is not likely
that appreciable concentratigns will be leached from the
soils inundated by the impoundment.Therefore,although
cadmium is know.nto bioaccumula te (principa 11y in non-muscle
tissues:liver,kidney,etc.),the element is not likely to
have adverse effects on the fish or fish predators in the
Susitna River.Zinc and copper are quite toxic but not
consistently known to bioaccumulate in fish tissue in newly
impounded reservoirs..
~Le_ac_b_iJ).g_o_f.b~'y)T me tat s is neither 'Rredictabl~~<:>'J:.
quantifiable.Leaching will be exacerbated by the presence
of humic substances,.which are abundant in the watershea,
but the toxicity o.f me tals bound to humics is usually much
lower than that of free metal ions (Jackson,et al.1978,
Moore and Ramamoorthy 1984).
The purpose for monitoring mercury and other metals will be
to identify whether or not uptake andbioaccumulation occur
-as··aresultoft:heproj-ect;_··
The main objective will be to analyze sufficient numbers of
preproject and with-project fish tissue samples to determine
if mercury and/or other metal bioaccumulation has occurred
and the extent of the occurrence.
Preproject data will ..be.developed from.two.sources:
o A review of scientific literature with application o·f·
this information to the Susitna Project
851021 E-3-2-300
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o Laboratory analyses to determine the present status of
mercury (and possibly other metals)in resident sport
fish in the Susitna River and adjacent lakes
With-project data will be used for comparison to natural
conditions.Fish muscle tissue burdens of toxic metals will
be developed from laboratory analyses of metal
concentrations in resident sport fish in the Susitna basin,
both in the Watana Reservoir and downstream.
Preproject sampling will begin with the 1990 field season
(see Table E.3.2.l30).It is expected that sufficient
samples will be collected within one season to provide
basel ine data.
Samples will be taken following filling of Watana (Stage I)
reservoir and then again after Devil Canyon and Watana
(Stage III)Reservoirs are filled.It is expected that
these samplings will be completed within one year.Plans
will be made to collect samples approximately five years
af ter Watana (S tage III)begins operation and periodically
thereafter,if necessary.This set of data will be used for
long-term comparisons.
(e)Dissolved Oxygen,pH,Organic Nitrogen (Total,
Particulate -Organic and Inorganic,and Dissolved),
and Phosphorus (Total,Particulate -Organic and
Inorganic,and Dissolved)(***)
Collection of data on these parameters is useful to
understanding changes that may occur in fish resources as
a result of the project.Sampling of both natural and
with-project conditions will take place coincidentally with
turbidity sampling.Winter sampling will be needed for
natural conditions to define baseline levels that in general
will otherwise be excluded for turbidity s~mpling.
(f)Water Quantity (***)
As part of normal project operation,mains tern discharges
will be continuously monitored at several locations,
including:
o Upstream of the Watana impoundment zone
o Watana Dam
o Devil Canyon Dam
o Gold Creek
851021 E-3-2-301
o Sunshine Station
TIl is information is needed to as sure that minimum and
maximum flow constraints are met.
(g)Fish Resources (***)
(i)Impoundment Area (***)
It is assumed that all existing habitat and fish
populations wi thin the impoundment zone will be
altered as the river changes from a flowing water
system to two reservoirs.It is also assumed that
although fish will inhabit the reservoir,the
productivity of the impoundments will-be low.
Furthermore,it was assumed that the potential for
effective mitigation measures in the impoundment
zones is low.,primarily because the reservoirs will
not be highly productive.Therefore,offsite
mitigation isuproposed.The need,scope,and extent
of monitoring for offsite mitigation will largely
depend on the mitigation option that will be
pursued.
(ii)Areas Downstream of the Project (***)
Based on aquatic baseline studies,impact
assessments,and harvest contributions,five
species·of Pacific salmon (-chum,sockeye,chinook,
coho,and pink),and Arctic grayling,rainbow trout,
Dolly Varden char,and burbot have been identified as
evaluation species for this project (see Section
2.4.2).
Not all species will be equally affected by the
proposed project.Mitigation measures have been
ci~~ign~ci ..1::9 t:l.Y9ici9;J;J!:Li,g.i.T!1i.2;~.imp..t:I.C:t~tQtl:1~~?._.
species with special emphasis given to juvenile
chinook and adult ch-i.tm salmon because oftheir----------------
dependence during certain life stages on habitats
directly influenced by mainstem flows.Once initia I
site selection was made and preliminary designs
completed,the priorities for developing mitigation
..measures have been:
o Flow regulation-to maintain habitat
o Structural habitat modifications,such as
slough modifications,to assure continued
production from natural systems
.[
851021 E-3-2-302
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851021
o Artificial propagation
Studies have shown that flow regulation accompanied
by habitat modification will have a high likelihood
of success in achieving the goal of no net loss in
habitat value.The Applicant would implement
artificial propagation as a last resort if the other
means of mitigation did not meet the Applicant's goal
of no net loss.To assure that this goal is met,
monitoring of both salmon and resident fish will be
implemented.
The primary study area for the fish monitoring
program is the middle reach of the Susitna River
(from Devil Canyon downstream to the confluence with
the Talkeetna and Chulitna Rivers).Of the
downstream areas,the fish populations in this reach
are the most likely to be affected by the project.
Therefore,concentrating monitoring efforts on this
reach will provide the best opportunity to determine
if mitigation measures are achieving their goal.
Chances of detecting changes in the lower river (Cook
Inlet to Talkeetna)due to operation of the project
are greatly reduced because the lower river is
influenced to a much greater extent by non-project
related instream and tributary conditions.
The primary emphasis of the Applicant's mitigation
plan has been to achieve no net loss in habitat value
due to the project.Therefore,it is felt that the
best indicator for this will be to monitor the number
of juvenile salmon produced from a given escapement.
In addition to the monitoring of salmon'populations,
key resident species will also be monitored.
The Alaska Department of Fish and Game (ADF&G)ha~
performed adult salmon spawner escapement studies on
the Susitna River dating back to 1974.Escapement
estimates were derived from survey data for the years
1974, 1975,1977,and 1981-1984.The escapement
estimates were determined from tag recovery data and
spawning ground surveys conducted by helicopter,
fixed-wing aircraft,and ground surveys.Survey
techniques and sampling designs were refined
periodically over the years,taking advantage of
increased understanding gained with each year of
study.Emphasis has gradually changed from a general
coverage of the entire system to more concentrated
coverage of the middle reach.
E-3-2-303
A study program has been conducted over the past
several years to provide information on the·habitat
and seasonal distribution and abundance of juvenile
salmon in the middle Susitna River.In 1983,the
SuHydro Study Team-(part of ADF&G)initiated a
program to provide estimates of fry-smolt production.
The program entailed marking outmigrant salmonids
(primarily chinook,chum and sockeye)in tributary
creeks and sloughs,and then recovering them
downstream at the Talkeetna Station (River Mile 103).
Methodology and statistical considerations have been
developed to the point where reasonably good
estimates can be obtained from a nominal survey
effort.
Abundance and distribution 0 f resident fish have been
extensively examined in the middle reach since 1982
(ADF&G 1984c).These studies have primarily involved
sampling at fixed sites between river miles (RM)98.6
-and 132.0.Three major macrohabitats (ma ins tem,
slough,and tributary mouths0 have been examined
usingmul tiplege'ar-types---(electroshocking ,seining,
hOdk-and-line,traps,fishwheels,outmigrant traps,
and trotlines).Although sampLing has been
intensive,only limited success has occurred in
developing esti-mates 0 f population numbers,primarily
because recapture numbers have b~en low.However,
extensive information has been developed on
-----------~-~-cat_ch-per -uni-tef-f0-l:'-t~,----s-i-ze-,~age-,distribut ion and
relative abundance of fish species.
Objectives:
Resident Fish.The objective of the resident fish
monitoring program is to provide an index of
pre-project and with-projec t populations of rainbow
trout and Arct~c grayling.__Totheextentpos~ible,____.._____bt"hers-pe-~{es-wiT:cbeexamrne(I:---F or-·example,-------
although Dolly Varden are -alsoevaruafion species-;---
estimates of population numbers are difficult if not
impossible because so few have been captured over
four years of intensive sampling at mul tiple
locations using a wide variety of sampling methods.
For burbot,a similar situation exists in that few
fish have heencapturedandto capture those few has
generally required use o:f!!!81I1P1i Ilg techniques that
sa-criffee -thefish~-----Therefo'tEf,--because --low numbers
of burbot are present,it is not justified to use
methods that could significantly impact the
resource.
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851021 E-3-2-304
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The monitoring period will extend over a period of
years encompassing natural and with-project"
conditions.Trends in population numbers will
be related to the index.The se trends will then be
used to determine if projec t effec ts have occurred.
To the extent possible,it will also be necessary to
follow patterns in the sport fishery harvest which is
anticipated to increase whether or not the Susitna
Project proceeds.
Salmon
-Adul ts
The objective of the adul t salmon monitoring
program is to provide spawning population
estimates (escapement estimates)of five salmon
species over a period of years encompassing natural
and with-project conditions.The estimates will be
used to assess the effect of the project on the
populations.The extended number of years is
necessary to de tect "real"trends in escapement
patterns that naturally vary considerably.It will
also be necessary to follow patterns in commercial
and sport fishery harvest that with time vary in
their effect on escapement.Determining what
factor or factors are affecting or controlling
population levels will be difficult.The level of
de tec tabi lity will depend 0 f the "na tural"
variability in the population,the degree of change
induced by the various factors controlling the
population,the variability induced by the sampling
program,and the number of years of study.
Sub-objectives include the following:
o Monitor the long-term trend in catch at fixed
fishwheel stations
o Monitor the long-term trend in spawning ground
counts
o Monitor the long-term trend in age and sex
composition of spawners
o Relate trends to physical,chemical and
biological changes in the system,including
changes induced by the project
851021 E-3-2-305
851021
-Juveniles
The objective of the juvenile salmon monitoring
program is to provide estimates of fry and smolt
production in the middle river-over a period of
years encompassing natural and with-project
conditions.Production estimates and changes in
production patterns over the years can be compared
directly with changes in physical conditions due to
project operation.In addition to production
estimates,survival rates obtained from the ratio
of egg production to fry-smolt production can be
monitored over the pre-and with-project period.
Sub-objectives include the following:
o Monitor long-term trends in the t,iming 0 f
emergence and outmigration of juvenile salmon
o Monitor long~term trends in the development,
growth,and relative condition of young salmon
Monitoring Locations:
Resident Fish.Resident fish sampling stations will
be located at the twelve sites between~RM 98.6 and
132.0 that have been examined since 1982.In
addition to continuing sampling at these index sites,
.i t-ha's-beenp'ropo sed~t-o--samp·letht'ee-addi·t-iona·l-
sites,beginning with the 1985 field season.This
will provide a total of 15 fixed sites.Furthermore,
any resident fish sampled during the salmon studies
(such as those captured in',the fishwheels and
outmigrant traps)will be incorporated into the
analysis.
_S a,ltn().l1.!.~p;:t.J1:l:l,j.l1g P.<l]?'1,l.!.;:t.t:i.<ll:l,§.J.tl:tl1~!1l~<!ci!~r i veE ....
will be studied from just upstream of the confluence
of the three main tributar-iesneai-the-town -0£------
Talkeetna to the Watana Dam site,including tributary
creeks and sloughs.Sampling by fishwheels will be
conducted at Curry Station and Sunshine Station.
Spc1iwning ground counts will be concentrated on
sloughs,,side channels,mainstem areas,and
tributaries of the middle river.Additional counts
wilL be .made ,as needed,.inperipheral areas such as
the Chulitiia arid Talkeetna subb,isiris:
The study area for the juvenile salmon monitoring
program includes the middle river and many of its
E-3-2-306
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851021
tributary creeks and sloughs.Young salmon will be
collected and marked in selected creeks and sloughs.
Recovery samples will be obtained at Talkeetna
Station.
Techniques:
Resident Fish.The type of sampling gear will depend
on the site to be sampled.Sampling methods will
include electrofishing,seining,fishwheels,
outmigrant traps,and hook-and-line.The type of
gear will be the same from year to year to maintain
consistency for analysis.The data analysis will be
focused on providing information on relative
abundance,distribution,and densities.This
information will be developed through a
mark-recapture program.Migrational patterns will be
analyzed by tag-and-recapture of tagged adult
resident fish.
Salmon.Fishwheels will be used"to capture adult
migrant salmon on their way upstream.Fish will be
counted by species and sex,and tagged with
individually numbered tags.Length;:of each fish will
be recorded.Weights and scale samples (for
determining the a:ge'of fish)will be obtained from a'
subsample 0 f each fish species collec ted.
If found to be feasible,sonar counters will be used
near the fishwheels to provide an independent
estimate of escapement.These counters may
eventually be used to replace some of the fishwheel
operations •
Spawning ground surveys will be primarily conducted
in the middle river.Air and ground visual surveys
will be the main survey method.Counts by species
will be obtained.Tag data (type,color,and
identification number)will also be recorded when
possible.
Emergence and outmigration studies in spawning areas
will be conducted.Salmon fry will be captured using
seines,minnow traps,and/or electrofishing gear.
Fry will be marked using tags (e~g.,coded-wire tags,
cold-branding,dye).
Salmon fry and smolts will be recovered in juvenile
traps located at Talkeetna Station.Total fry
production for each species will be estimated.
E-3-2-307
Timing will be determined from catch-per-effort data
compiled from spawning area samples and from the
downstream traps.
Schedule:
The preproject monitoring schedule for both salmon
and resident programs will begin during the 1985
field sampling season and continue each year into the
construction phase of the project (see Table
E.3.2 .130).With-project monitoring will commence in
the year immediately following the last preprojec t
year.
Data Analysis/Interpretation:
Preproject data will be compared to with-project data
to determine if significant changes are occurring as
a result of the project.In addition,the data
collected from the above studies,data from the
commercial fish harvest,sportfish harvest surveys,
and subsIstencE{fishing will be considered in the
overall evaluation of the salmon resources.
(h)Monitoring of Structural Habitat Modifications (***)
The Applicant has proposed plans for specific structural
habitat modifications to protect middle river fish resources
---~-(WCC-T981'-ar~-'One-of-~tn(FnigJjer prtoritymiTigationoptious
will be to structurally modify slough habitats so that they
continue to provide fish habitat at existing or higher
levels.If this option is implemented,the following
monitoring plan for slou~h modifications is proposed.
The various features incorporated for slough habitat
enhancement will be monitored to de termine whe ther they are
..---------meeting -their-intended ...func.tion.ancLar-eoperatingpr_oper_ly.
.._Mit.igatLo.n._fea.tu.r_es__de_s_ig:ne_d__t.~La_U.9~_adu 1 tJ;la 1mon _~c ce ~..._....
into the sloughs will be inspected annually after breakup to
identify and.implement any needed repairs prior to the
adults'return.Annual monitoring of returning adults will
identify access problems or passage delays and appropriate
corrective actions will -be taken.
Slough moc1i fIca !::ion designed to Illain:t.iin spawning areas will
1>eilJ,§J peC l:ec1cllJ,lJ,1.1ally·priortothe=·13P.a~ing .sea s orlto ver iJy
that the area contains suitable spawning conditions such as
adequate flow (oepth and ve10city)and suitable substrate.
If flows oiminish so that spawning is no longer possible,
appropric9.te corrective action will be taken so that adequate
-j
851021 E-3-2-308
flow and substrate are restored.The annual slough
monitoring program will include an evaluation of general
slough conditions including beaver occupation and general
condition of the spawning and rearing areas.Appropriate
corrective actions will be performed to maintain slough
productivity.For example,if productivity is decreased due
to increased silt deposition,gravel cleaning in the slough
will be undertaken.
The number of spawning adults returning to the modified
sloughs will be monitored annually to determine if the
combination of minimum flow and slough modifications is
maintaining natural levels of production.This monitoring
will also serve to determine whether the capacity of the
modified areas is being exceeded.Fry production will be
monitored annually to verify incubation success.Fry
monitoring will include an assessment of out-migration
timing and success.
Following initiation of river flow regulation by Stage I
Watana Dam,representative sloughs will be instrumented with
temperature and flow recording instruments to monitor
physical characteristics of the sloughs throughout the year.
Monitoring of the physical processes will be continued until
slough conditions stabilize under the regulated flow regime.
TIl is physical process monitoring will be used in par.:.t to
determine whe ther further modifications to .the physical
habitat can be made to assist in maintaining slough
productivity.
(i)Fluvial Geomorphology (***)
The Susitna River is a dynamic system that is undergoing
continual morphological changes due to physical processes
such as ice and floods.These changes will be altered by
with-project flow regulation.Therefore,it is important to
document these changes on a periodic basis.
The primary means of providing this documentation will be
through detailed air photography of the river from the upper
end of the Watana Reservoir to Cook Inlet.Numerous photo
series of the basin are already available.
Existing photos of the middle and lower river will be used
as a baseline.For comparison,additional photos will be
taken periodically.This will be performed in conjunction
with air photography for wildl He studies.
851021 E-3-2-309
(j)Special Monitoring Studies (***)
It is anticipated that there may be a need for other
additional monitoring studies or modifications to this
proposed draft.During the annual review process wi th the
resource agencies,proposals for these studies will be
considered.If approved,these proposals will be
implemented during following years.
(k)Contingency Planning (***)
Although long-term monitoring results will be reviewed on
an annual basis,there maybe some unforeseen instances in
which additional monitoring may need to be initiated on a
shor.t-term notice.In those cases,the Director of
Environment and Licensing (DEL)(see Section 2.6.1)will
notify the'appropriate agency or agencies and,the situation
will be discussed and agreed upon action taken.If the
unforeseen instance is first observed by the resource agency
(e.g.,by ADF&G fishwheelcrews),the agencies should notify
the DEL and request a meeting to address the situation.It
is ,the.intent of the Applicant to resol.ve.these situations
on a case-by-case basis wi th the appropriate agencies.For
cases that cannot be resolved in this manner,the FERC will
be consul ted.
2.7 -Cost of Mitigation (***)
.T~:L d~velop~~~ti"!!l1;ll:;~§QJ"!!litig1;ltj._QJL~Q~Ll:;,.l985co$.b es tiIIl~l:;'g§"W~..!:gpr.g
pared for each activity (Tables E.3.2.l24,E.3.2.l26,E.3.2.l29).
These cost estimates were based upon unit cost information derived
from recent experience in Alaska or~'upori experience eljH~where and/or
earlier,and.escalated to arrive atl985 cost estimates for South-
central Alaska.Costs for the mitigation program were separated into
construction cost and average annual operating cost.For the major
mitigation activities,these costs are:
Downstream Mitigation (Table E.3.2.126)
Impoundment Mi,tigation (Table E.3.2.l26)
Dam Structure-Multi-level intakes and
fixed cone valves (Table E.3.2.l26)
Water &Fisherit;s Quality Monitoring
.(-'rable E.-3.:2 •.124)
.Total Cons.truction-Cost--
$1,088,000
940,000
80,100,000
.11,600,000
$93,728,000 1
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851021 E-3-2-3l0
Average Annual Operating Costs
Longterm Fisheries Monitoring
(Table E.3.2.129)
Operation and Maintenance of Facilities
(Table E.3.2.l26)
Total Average Annual Operating Cost
$1,2~O,000
50,000
$1,270,000
These costs do not include any contingency costs or owner's administra-
tive costs.
The costs for downstream mitigation (Table E.3.2.126)are based on
modifications to Sloughs 8A,9,9A,11,21 and side channels 11 and 21.
Details of these costs are provided in Table E.3.2.131.
The schedule for implementing the aquatic monitoring program is
described in Table E.3.2.132.
2.8 -Agency Consultation on Fisheries Mitigation Measures (**)
Four agencies,USFWS,ADF&G,Alaska Department of Natural Resources
(ADNR)and National Marine Fisheries Service (NMFS)have provided
comments on fisheries mitigation measures.The following sections
contain comments by the agencies and responses by the Applicant
concerning ~quatic mitigation.These are the major comments made prior
to submission of this license ·amendment.Additional comments and
consultation are described in Chapter 11.
2.8.1.-U.S.Fish and Wildlife Service (**)
The USFWS provided formal comments on fisheries mitigation mea-
sures on October 5,1982,January 14,1983 and December 18,1984.
The USFWS comments are divided into construction-related
mitigations and operation-related mitigations.
(a)Construction Mitigations (0)
Construction mitigations primarily concern siting,design,
and scheduling.The comments are:
o Siting and Design (0)
The access road and transmission line between Watana
and Devil Canyon should use the same corridor.
The diversion tunnel should be screened to avoid
entraining fish.The siting of construction and
permanent villages and other facilities should be
reviewed with the goal of minimizing impacts.
851021 E-3-2-311
o Scheduling (***)
construction activities and reservoir clearing should
occur in the winter to minimize impacts.Work in
aquatic systems should be scheduled to avoid conflicts
with sensitive life history stages.
These comments are addressed in Section 2.4.3.The
BMP manuals,prepared by the Applicant in coordination
wi ththe resource agencies,specify environmentally
acceptable construction practices to be used
throughout project construction.During the detailed
design phase of the project,a.criteria manual will be
prepared to present the siting and design criteria.
This manual wi 11 include the timingandschedul ing of
construction activities based on the identified
sensitive periods and the needs of the cons truction
contractor.
(b)Operation Mitigations (**)
Comments on·operation·mitiga tions·were di vided into those
concerning reservoir mitigations and downstream
mi tigations.
(i)Rese.;cvoir Mitigations (**)
Recommendation:The viabi~ity of a reservoir fishery
needs to be evaluated •.
Response:The Watana arid Devil Canyon reservoirs
were evaluated in terms of their suitability as
fish habitat.It was concluded that the drawdown
cycle and turbidity levels in the reservoirs will
limit fish populations and·will probably not support
a quality reservoir fishery.A grayling fishery,
however,would develop in,and at the mouths of,····trIbuEarIes·cU:sc-hargT;ig··lnto·-the·re ser voIr :--....
(ii)Downstream Mitigations (**)
Recommendation:Mitigation options for the dewatered
area between the Devil canyondam and its
powerhquse need to be considered.
Respotls~:The habitat lost between Devil Canyon dam
artdthepowerhouseis .typified by'velCfcities between
9 and 16 ft/sec (2.7 and 4.8 m/sec),the substrate is
bedrock.The area is not expec ted to provide
significant fish habitat,thus the dewatering of the '\
851021 E-3-2-312
.1
851021
section is not expected to result in substantial
impacts.The few chinook that migrate through the
canyon will be blocked by the dam.Milling areas
will still be available at the powerhouse outlet.
Because of these factors,mitigation measures are not
proposed.
Recommendation:The potential to establish/expand
the salmon fishery between the Devil Canyon and
Watana damsites,in the absence of a Devil Canyon
dam,needs to be addressed.
Response:The flows downstream from Watana Dam are
expected to permit chinook salmon to ascend to
Tsusena Creek,at the base of the dam.If the Devil
Canyon dam is eventually eliminated from the planned
development,it would be possible to establish a
fishery in this reach.Since Devil Canyon dam is a
part of the present plan,developing these chinook
stocks for the period between Watana development and
Devil Canyon development is not considered cost-
effective mitigation.
Recommendation:Adjustments to the Watana reservoir
filling schedule to minimize impacts to fish resour-
ces should be considered •.Addition of a low-level
intake po rt sh~uld be eval ua ted.
Response:initial filling of the Watana-Stage I
reservoir is expected to take one season,whereas
Stage III is expected to slowly fill over several
years.With these filling schedules,Case E-VI flow
constraints will be followed,thereby maintaining
downstream aquatic habitat.Any additional
lengthening of the filling period would only delay
but would not reduce impacts to grayling.
Lengthening the filling period would potentially
increase downstream impacts to salmon,if Case E-VI
constraints could not be met.A low-level intake
port is not considered necessary due to the revised
filling schedule of the three stage project which
eliminates the cold tempertures due to the second
year 0 f f illi ng.
Recommendation:An expanded discussion of the salmon
hatchery mitigation option should be provided.
Response:The salmon hatchery mitigation option is a
low priority compensation alternative.It is
anticipated that the proposed mitigation will
E-3-2-313
851021
maintain salmon populations in the historical
locations and that a hatchery will not be n~eded.
Nevertheless,an independent hatchery siting study
has been completed for the Fishery Rehabilitation and
Enhancement Division (FRED)of ADF&G.(Kramer,Chin
and Mayo,Inc.1983).
Recommendation:Slough modifications to increase
fish habitat need to be demonstrated.It has been
suggested that a demonstration project be developed
in the middle reach of the Susitna River.
Response:At an appropriate time,the Applicant
intends to test slough modification measures with a
demonstration project.
Recommendation:Impac ts to species lis.ted in the
F&WS Categories 3 and 4 should be discussed.
Response:~otential impacts for all secondary
evaluation species/life stages are addressed ..in the
draft Middle River Fish Mitigation Plan (APA
1985g).
2.8.2 -Alaska Department of Fish and Game (**)
'!he Alaska Department 0 f Fish and Game (ADF&G)pt'ovided comments
on mitigation measures on July 27,1982,January 13,1983 and
.~..----December.~31.,-1.9,8.4_.__.The.AD.F.&G_comment.s_.r_el_a t edto_mLtig_at itm .0 f
lost grayling habitat and mitigation for alterations to
downstream salmon habitat.
Recommendation:.Increasing access and public facilities for
recreational.fishing in the Susitna Basin,along with habitat
improvements to enhance salmon spawning habitat,are the
preferred compensation measures to offset losses in the
impoundment zones..ADF&G does not support stocking the
'--impoundmen"Es]iuc,f"-d'oes'-iio""""t"favor-a:"rairi:l)o\:;r-Eroiit-'sEockirig 'flrograrif
....----'--asami"t"tga eion-olftt-011.-;--·..:.....---:-------·-··-·-··----··--.----.-
Response:The approach to impoundment mitigation has been
modified to reflect the ADF&G'.s preferred measures of
compensation.The option of stocking rainbow trout has been
dropped.
Recommendation:I.tls t:-r:earn flowsandt~lIlP~-r:atures required to
maintain present populations should be carefully evaluated to
provide a basis for further mitigation measures.
E~3-2-314
!
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Response:Extensive studies and analyses on instream flow and
temperatures have been made (see Section 2.3).These have been
used to formulate the Fish Mitigation Plan (wee 1984a).
Recommendation:If onsite mitigation of fisheries impacts cannot
be accomplished,hatcheries should be considered.
Response:The salmon hatchery option is a low priority
compensation alternative.It is anticipated that mitigation in
the form of instream flow releases and habitat modifications will
be effective at maintaining production of slough and mainstem
spawning salmon.These mitigation measures are presented in the
Fish Mitigation plan (wee 1984a).
Recommendation:The ADF&G supports the selection of chum
spawning and chinook rearing as the species/life stages of
primary importance.Impacts to other anadromous and resident
species/life stages need to be evaluated.
Response:Potential impacts for all secondary~valuation
species/life stages are addressed in.the draft Middle River Fish
Mitigation Plan (APA 1985g).
Recommendation:The ADF&G's preferred mitigation options to
avoid or minimize downstream impacts are to provide sufficient
instream flows to maintain habitat requirements of species/life
stages and implement structural habitat :modications ..'
Response:The Applicant is pleased that the Department agrees
that instream flows combined with habitat modifications is a
feasible approach to achieving the goal of no net loss 0 f habitat
value.
Recommendation:The mitigation plan should contain a detailed
monitoring and contingency plan.
Response:A monitoring plan has been prepared and outlines the
evaluation process for determining the success of mitigation
measures.If mitigation measures are not effective in achieving
their intended goal,contingency plans will be in place to either
improve the measures or implement other mitigation options.
Recommendation:A pilot program to test the effectiveness and
feasibility of mitigation measures should be undertaken.
Response:At an appropriate time,the Applicant intends to test
slough modification measures with a demonstration project.
851021 E-3-2-315
Recommendation:During habitat modifications riparian vegetation
must be rehabilitated if disturbed,and stipulations for the
disposal of gravel and spoils should be developed.
Response:The Applicant has prepared a BMP manual on Erosion and
Sedimentation Control which de tails me thods to dispose 0 f gravels
and spoils and rehabilitate disturbed sites.These practices
will be a required stipulation of all projects undertaken by the
Applicant.
2.8.3 -Alaska Department ofN'atural Resources (**)
The Alaska Department of Natural Resources'comments of
January 13,1983,requested that downstream mitigation,other
than slough modifications,be included.The discussion of
downstream mitigation has'b~en substantially revised to indicate
more clearly that a series of habitat enhancement techniques will
be undertaken,rathe~than construction of an artificial spawning
channel.Also,replacement habitats will provide new habitat in
previouslyunutilized areas.
2.8.4 -National Marine Fisheries Service (***)
The National Marine Fisheries Service (NMFS)provided formal
comments of fisheries mitigation planning on December 31,1984.
The NMFS comments related to downstream mitigation planning.
Recommendation:Clarification should be provided on primary and
seconda·r-y evaluat-ion-s'pec-ies···and·howt-he·se-·s·pec-ie·s--wer-e
selected.
Response:The rationale for selecting evaluation species has
been presented in the Fish Mitigation Plan (WCC 1984a)•
.Mitigatiorimeasures will be developed for se(:ondary species if
impacts are identified •
.___.._Recommendation:._J.I:!.~~.¥.~_~~p;:~~~~4c~c:>~~.E!.!:"!1__.~~~'!~_..4.E!.~~~E!t:~!1g
incubating embryos during winter with minimum project flows •
......._---_._.....------:::--..Refinement of project flow releases are needed.
Response:Project release schedules'have the objective of
establishing minimum flows such that survival of.embryos
deposited at spawning flows will not be compromised at.reduced
incubation flows.Under natural conditions,redd dewatering is
known to occur.It is anticipated that witl1.-project flows willafter'thIs"natural ..condl.t:i.()nancr-·pi-ovlde positIve'benefi ts by
'mairi"ta"iniiig'flowcsf Or ..redasTtes"~~"""'"...c'cc~.•L..c,....c.
Recommendation:The mitigation plan should address rearing
habitats in greater detail and discuss mitigation measures
.J
.j
,j
851021 E-3-2-3l6
r
J
designed to maintain rearing conditions in known important
rearing areas.
Response:At this time,it is anticipated that mitigation for
rearing can be achieved by flow releases.Should flow releases
prove to be inadequate in maintaining or replacing rearing
habitats,additional mitigation measures will be developed and
incorporated into the fish mitigation plan.
Recommendation:Support the inclusion of additional sloughs and
side channels for habitat modifications.
Response:It is anticipated that the habitat modifications
proposed at selected sloughs and side channels will improve the
habitat value substantially beyond that which is presently
avai ~able.
Recommendation:The periodic removal of fines and organic
material should be discussed further.
Response:Removal of fines and organic material from sloughs
that would not be overtopped under project flows can be
accomplished by:(1)the spawning action of fish themselves;(2)
the use 0 f gated berms to provide fl ushing flows;and (3)the use.
of a mechanical gravel cleaning machine as proposed in the
original License Application.,.
Recommendation:An evaluation of project impacts from an altered
temperature regime should be discussed in the Fish Mitigation
Plan.
Response:Control over downstream temperatures through
multi-level intake structures is an important mitigation feature
and has been extensively analyzed by the Applicant.Discussion
of the results of these analyses are presented in Chapter 2 of
Exhibit E.
Recommendation:Impacts associated with filling flows of the
Watana Reservoir and load following should be addressed in The
Fish Mitigation Plan.
Response:Impacts and mitigation measures associated with
filling the Watana Reservoir and load following will be
incorporated into an updated Fish Mitigation Plan.
Recommendation:NMFS supports a demonstration project to test·
the effectiveness of the mitigations options.
851021 E-3-2-317
Response:The Applicant intends to test the effectiveness and
feasibility 0 f mitigation measures proposed for slough
modifications at an appropriate .time 0
:-1
851021 E-3-2-318
TABLES
TABLE E.3.2.1:CO~ION AND SCIENTIFIC NAMES OF FISH
SPECIES RECORDED FROM THE SUSITNA BASIN
II.....J
I i
i I
Scientifi:c Name
12
Petramyzontidae
Lampetra japonica
Salmonidae
Coregonus laurettae
Coregonus pidschian
Oncorhynchus gorbuscha
Oncorhynchus keta
Oncorhynchus kisutch
Oncorhynchus nerka
Oncorhynchus tshawytscha
Prosopium cylindraceum
Salmo gairdneri
Salvelinus malma
"8alvelinus namaycush
Thymallus arcticus
osmeridae
Thaleichthys pacificus
Esocidae
Esox lucius
Catostomidae
Catostomis catostomus
Gadidae
Lota Iota
Gasterosteidae
Gasterosteus aculeatus
Pungitius pungitius
Cottidae
Cottus sp.
Source:Morrow 1980
Common Name
Arctic Lamprey
Bering cisco
Humpback Whitefish
Pink Salmon
Chum Salmon
Coho Salmon
Sockeye Salmon
Chinook Salmon
Round Whitefish
Rainbow Trout
Dolly Varden
Lake Trout
Arctic Grayling
Eulachon
Northern Pike
Longnose Sucker
Burbot
Threespine Stickleback
Ninespine Stickleback
Sculpin
TABLE E.3.2.2:COMMERCIAL CATCH OF UPPER COOK INLET SALMON IN NUMBERS OF FISH BY SPECIES,
1954 -1984.
1954 63,780 1,207,046 321,525-2,189,307 510,068 4,291,726
1955 45,926 1,027,528 170,777 101,680 248,343 1,594,254
1956 64,977 1,258,789 198,189 1,595,375 782,051 3,899,381
1957 -42,158 643,712 125,434 21,228 1,001,470 1,834,022
1958 22,727 477,392 239,765 1,648,548 471,697 2,860,129
1959 32,651 612,676 106,312 12,527 300,319 :J'1,064,485
1960 27,512 923,314 311,461 1,411,605 .;~.659,997 3,333,889
1961 19,210 1,162,303 117,778 34,017 349,628 1,683,463
1962 20,210 1,147,573 350,324 2,711,689 970,582 5,200,378
1963 17,536 942,980 197,140 30,436 387,027 1,575,119
1964 4,531 970,055 '452,654 3,231,961 1,079,084 5,738,285
1965 9,741 1,412,350 153,619 ~23,963 316,444 1,916,117
1966 9,541 1,851,990 289,690 2,006,580 531,825 4,689,626
1967 7,859 1,380,062 177,729 32,229 296,037 1,894,716
'1'96S 4,53-6 1~r04;904 470,450 2,278,197-1,119,ll4 4,977,201
1969 12,398 692,254 100,952 33,422 269,855 1,108,881
1970 8,348 731,214 275,296 813,895 775,167 2,603,920
1971 19,765 636,303 100,636 35,624 327,029 1,119,357
1972 16,086 879,824 80,933 628,580 630,148 2,235,571
1973 5,194 670,025 104,420 326,184 667,573 1,773,396
1974 6,596 497,185 200,125 483,730 396,840 1,584,476
1975 4,780 684,818 227,372 336,359 951,796 2,205,135
1916 10,861---1-,664,150 --·-208 ,710 ---1,256,744---.,--469,807 3,610,278
-~-~-_._---~-----------1.91"1..,14-,-7-92,.--~-2-,054,,-020---192i,9'5 -544.,,184.-1,233.,.'233 '1 ,_049_,_70.4
1978 17,303 2,622,487 219,234 1,687,092 571,925 5,118,041
1979 13,738 924,415 265,166 72,982 650,357 1,926,658
1980 12,497 1,584,392 283,623 1,871,058 387,078 4,138,648
1981 11,548 1,443,294 494,073 127,857 842,849 2,919,621
1982 20,636 3,237,376 777,132 788,972 1,428,621 6,252,737
1983 20,396 5,003,070 520,831 73,555 1,124,421 6,742,273
1984 (1)8,800 2,103,000 443,000 623,000 684,000 3,861,800
1
:1
-,I
I
]
)
~
-j
~
j
,1
1
1
)
'j
'j
I
1
1
Total
3,059,170659,190
Pink
....
263,785 even-1,576,646
cx::3d-120,4161,340,339
(1)ADF&G Preliminary Data.
SCA.1rCe:ADF&G 1984p
Average 19,247
Year
'~:_-'--"
~
TABLE E.3.12.3:SUMMARY OF COMMERCIAL AND SPORT HARVESTS ON SUSITNA RIVER BASIN ADULT SALMON RETURNS
Commercial Harvest Sport Harvest
Upper Estimated Estimated Estimated Estimated Susitna
Cook Inlet Percent Susitna Susitna Susitna Total Basin Sport Percent of
Species Harvest l Contribution2 Harvest Escapement Run Harvest4 Escapement
Sockeye ~Range
287,0003811,443,000 20 (l0-30)288,600 575,600 1,283 0.4
82 3,237,000 20 (10-30)647,400 279,0003 926,400 2,205 0.8
83 5,003,000 10 (10-30)500,300 185,0003 685,300 5,537 3.0
84 2,103,000 20 (10-30)420,600 605,8005 1,026,400
Pink
127,000381128,000 85 108,800 235,800 8,660 6.8
82 789,000 85 670,650 1,318,0003 1,988,650 16,822 1.3
83 74,000 85 62,900 150,0003 212,900 4,656 3.1
84 623,000 85 529,550 3,629,9005 4,159,450
Chum
297,000381843,000 85 716,550 1,013,550 4,207 1.4
82 1,429,000 85 1,214,650 481,00Q3 1,695,650 6,843 1.4
83 1,124,000 85 955,400 290,OoeP 1,245,400 5,233 1.8
84 684,000 85 581,400 812,7005 1,394,100
Coho
68,0003 j15,00081494,000 50 247,000 9,391 13.8
82 777,000 50 388,500 148,0003 536,500 16,664 11.3
83 521,000 50 260,500 45,0003 305,500 8,425 18.7
84 443,000 50 221,500 190,1005 411,600
Chinook
81 11,500 10 1,150 ------7,576
82 20,600 10 2,060 ------10,521
83 20,400 10 2,040 ------12,420
84 8,800 10 880 250,0006 251,000
1 Source:ADF&G Commercial Fisheries Division
2 B.Barr tt,ADF&G Su Hydro,February 15,1984 Workshop Presentation
3 Yentna tation +Sunshine Station estimated escapement +5%for sockeye,+48%for pink,+5%for chum
+85%f r coho (Source:B.Barrett,ADF&G Su Hydro,February 15,1984 Workshop Presentation).
4 Mills 1 82,1983,1984
5 Flathor Station (RM 22)Escapements (ADF&G 1985b)6 Source:ADF&G 1985b
~,::,"#:"•.;
I
TABLE E.3.2.4:ANNUAL SUSITNA BASIN SPORT ~ISI1 HARVEST AND EffORT BY fiSHERY AND SPECIES -1978 TO 1983.
!.
Locations
Days
Fished
j ;
Chin'oole
Sallnon
I '
Coho
Salmon
Sockeye
Salmon;
Pinle
Salmon
Chum
Salmon
Rainbow
Trout
Dolly
Varden
Lalee Arctic
Trout Grayling Burbot
905 56 18,901 2.458 913 280 0 208 9
2,451 85 15,619 4,429 1,193 633 O'958 9
2.~00 28 2,074 1.912 1.501 1.811 0 859 27
418 14 6,981 1,697 470 108 0 461 18
151 28 3,142 1,015 334 63 0 334 0
'.798 0 697 0 3.634 0 0 579 0
2.212 254 2.833 1.015 2,721 154 36 2,115 45
2,401 183 1,146 215 2,640 136 0 1,871 0
88 141 31·234 0 235 0 99 0
i 4;r
1408!
12
;256
o
1850 *
1326 *
1769*
12*
22,682
25,762
5,040
11.869
5,687
9,111
8,767
6,914
732
13,161 .0 0 0 0 0 0 0 2.522 2,278 2,947
~Cl70 ij63 2.188 56 3.994 2.692 1.519 2.739 871~3.770 208
1978
WI llowCreek
Caswell Creele
Montana Creele
Sunshine Creek
Clear (Chunilna)Creek
Sheep Creek
little Willow Creek
Oeshka River
lake Creek
Alexander Creek
Talachulitna River
Lake Louise.Lake Susitna
Tyone River .
Others
1978 Total 124,695 2)843 15,012 845 55.418 15,661 14,925 6.165 3.435 13,532 3,263
;
I
lli2.
WHlow Creek 18.911 1 459 462 94 3,445 582 1.500 618 0 1.654 18CaswellCreek3,710 i 156 624 0 100 9 282 91 0 354 0MontanaCreek22,621 1312 1,.135 346 2.412 745 1.536 521 0 791 9SunshineCreek3,317 I 10*174 151 700 55 382 264 0 0 45Clear(Chunllna)Creek .5.125 j312 1,248 31 645 355 1,373 827 0 1,045 9SheepCreek6.728 i 10 462 31 2,418 682 513 127 0 645 64LittleWillowCreek5,171 0 262 141 745 118 345 336 0 1.091 0DeshkaRiver13.236 2l81~973 0 109 0 3.182 0 0 1,463 82LakeCreek13,881 1~796 2,671 440 882 136 4.527 164 9 1,963 109AlexanderCreek8,284 i 71~1,560 19 236 45 1,182 ·182 0 745 145TalachulitnaRiver2,185 i 293 125 47 100 55 0 155 0 664 45LakeLOUise.Lake Suaitna,i '
Tyone River .12,199 I ,0 0 0 0 0 0 0 2,618 2,936 2,363,Others 1 I 12.639 i 39 1.997 '220 664 1.245 3.412 909 412 4.918 282
1919 Totlll '128,001 6].91 10 12,893 1,586 12,516 4,072 18,354 4.200 3.099 13,342 3,171
I
:*Chinook less than 20 'inches
"j
---,-'~~"---'---"~---"-
."------_.-....~--------
-__,__r
_._-~~-'-"'-'''-;'~.-...-'~>---~---
\I,
,
TAB E E.3.2.4 (Page 2 of 3 )
I
,.;----------
Days Chinook Coho Sockeye Pink Chum Rainbow Dolly Lake Arctic
Locations Fished Salmon Salmon Salmon Salmon Salmon Trout Varden Trout Grayling lIurbot
!2ID!
WI llow Cree 29,011 289 1.201 83 23,638 989 1,168 636 0 1.868 0
Caswell Cre k 4,963 215 1,124 11 1.663 19 154 83 0 353 26
Montana Crelk .19,287 559 2,684 257 8,230 571 854 161 0 655 13
Sunsh I ne Crl ek 5,208 132 1,534 116 2,408 225 193 39 0 0 39
Clear (Chun lna)Creek 4,388 172 661 6 622 385 950 751 0 1,348 32
Sheep Creek 8,041 45*430 9 6,362 648 385 83 0 725 45LittleWUIIwCreek8.190 32*494 77 6,420 270 353 122 0 1,156 0DeshkaRive19,364 3.685 2,290 0 689 0 4,305 0 0 1.811 224LakeCreek8,325 115 2,351 267 2.101 69 2,144 121 9 1,912 0AlexanderCIeek6.812 1.438 999 52 809 121 1,945 353 0 1,145 0TalachulitO!River 2,542 121 491 112 276 17 379 982 0 1,713 0LakeLouise,Lake Susftna,
Tyone Rivl r 10.539 0 0 0 0 0 0 0 2,609 4,477 6,:gOthers1221645*2 234 251 3 403 1 445 2 658 790 261 4 854
1980 Total ·138,886 7,389 16,499 1,304 56,621 4,759 15,488 4,127 2.816 22,083 7,203
Days Chinook Chinook .Coho Sockeye Pink Chum Rainbow Dolly Lake Arctic
Locations Fished .Salmon·Salmon Salmon Salmon Selmon Salmon Trout Varden Trout Grayling Burbot
1981
Willow Creel 14,060 144 441 747 11 2,797 1,533 .1,475 249 0 1,188 4f
Caswell Cre4 k 3,860 77 172 901 38 335 "0 326 38 0 144 (
Montana Cre4k 16.651 239 422 2.261 182 1,782 805 1,111 240 0 891 (
Sunshine Cr4 ek 3.062 57 0 968 220 958 125 249 10 0 57 11!
Clear (Chun lna)Creek 3.584 86 287 422 29 19 57 1,226 1,418 0 996 (
Sheep Creek 6,936 0 0 326 105 1,236 987 201 57 0 872 (
Little WUll w Creek 3,845 0 0 29 67 604 192 374 48 0 623 (
Deshke Rive 13,248 738 2,031 632 0 ;'9 o \
3,631 10 0 1,255 9lLakeCreek6,411 163 632 1,035 211 412 48 2,874 .\67 19 1,600 2'
Alexander CI eek 6,892 218 843 891 67 57 10 2,290 287 0 1,130 2'Talachul itnl River 1,318 57 0 240 172 29 0 0 0 0 479 I
Lake Louise,Lake Susitna,
Tyone Rlvtr 14,391 0 0 0 0 0 0 0 0 4,093 4.892 5.29:Others 7 850 277 0 939 115 412 450 3 851 814 287 1 OA9 l§
1981 Total 102,240 2,748 4.828 9,391 1.283 8,660 4,207 13,757 3,238 4,399 21,216 5,66·
•Chinook lt 55 than 20 inches.
TABLE E.3.2.4 (Page 3 of3)
..
--I
Days Chinook!Chinook Coho Sockeye Pink Chum Rainbow Dolly Lake Arctic
Lo'cations Fished salmoni Salmon Salmon Salmon Salmon Salmon Trout Varden Trout Grayling Bus-bot
i
!ill I,I"Hlow Creek 19,104 220
1
409 1,069 94 4,189 2,086 891 262 0 1,520 63
Ca 1sweU Creek 5;101 118 293 116 52 1,092 0 189 13 0 252 0
Montana Creek 23,645 126 115 3,060 514 3,595 1,708 2,243 356 0 849 ,0
Sunshine Creek'3,187 52 0 1,719 189 1,132 231 545 42 0 42 13
Cll'ar (Chunilna)Creek 3,856 52 398 996 115 220 31 608 1,069 0 943 0
Sh~ep Creek 9,093 0 0 361 88 2,599 1,750 325 409 0 123 0
LI~tle WllloNCreek 5,579 0 0 '398 1Q5 1,520 199 335 189 0 371 '0
Deshka River 18,391 1,142 3,165 2,463 0 311 0 3,804 0 0 1,457 252
Lake Creek 8,649 356 1,289 1,603 252 398 199 3,134 482 0 1,955 0
Al~xander Creek 10,148 681!1,825 1,901 335 482 0 2,505 42 0 1,582 84
Talachulitna River 1,911 Oi 0 '524 63 220 0 0 31 0 587 0
Lake Louise,Lake Susitna,
14,024 01lyoneRiver 0 0 0 0 0 0 0 4,056 3,532 5,565
Others,9.980 220i 0 1.782 398 398 639 2.400 1.666 335 5.041 63
I
19.82 Total 1.34,468 3,021!1,494,16,664 2,205 16,822 6,843 16,979 4,621 4,391 18,860 6,100
i
1983 i
I-".;
"Iillow Creek 136113,405 398 576 425 1,647 1,490 1,689 336 0 1,794 21
Caswell Creek 5,048 101 262 408 151 126 0 231 157 0 315 31
Montana Creek 17,109 199i 305 1,402 534 902 1,311 1,332 325 0 336 C
Su.nsh i ne Creek 3,429 1051 0 722 685 241 42 178 84 0 31 367
Cl~ar (Chunilna)Creek 1,564 2521 682 836 534 73 650 .1,836 1,962 0 1,553 8~
Sheep Creek 6,231
93il
0 596 310 682 902 409 52 0 839 1C
Li~tle~illoN Creek 2,791 0 52 110 157 147 514 73 0 84 (
Deshka River 23,114 3,955 1,036 0 21 0 2,434 0 0 1,280 12t
lake Creek 14,749 535'1,888 1,392 726 430 52 2,287 262 0 2,224 28:
Aliexander Creek 9,425 6721 1,039 408 69 126 0 608 136 0 483 (
T&lachulitna River 4,556 63i 213 84 41 0 0 0 105 0 3,118 (
K~shwltna River 1,344 2311 0 52 0 0 0 357 3~4 0 514 (
l~ke Louise,Lake Susltans
01iTyoneRiver12,948 0 0 0 0 0 0 0 3,210 4,217 4,071
Others 12.367 3031 118 861 1,892 251 639 4.625 1,061 281 3.387 53·
I
19.83 Total 134,156 3,4401 8,980 '8,425 5,537 4,656 5,233 16,500 4,863 3,497 20,235 5,52..1
...!Chinook less than 20 inches
Sc)urce:MILLS 1979,1980,1981,]'982,1983,1984
,\
Table E.3.2.5iSp'rt fish harvest for Southcentral Alaska and Susltna Basin In numbers of fish by species,1978-1983.
Arct Rainbow Trout Pink Salmon Coho Salmon Chinook Salmon Chum Salmon SockeYt Salmn
South South-Susitna South-Susitna South-Susitna South-Susitna South-Susltne South'Sualtr
Vear centra central Basin central Basin central Basin central Basin central Basin central Basir
1978 47.866 13,532 101,243 14,925 143,483 55,418 81,990 15,072 26,415 2,843 23,155 15,661 118,299 84!
1979 70,31j 13,342 129,815 18,354 63,366 12,516 93,234 12,893 34,009 6,910 8,126 4,012 17,655 1,581
69.46 22,083 126,686 15,488 153,194 56,621 'F;8,660 4,159 105,914 1,301980127,958 16,499 24,155 (/7,389
1981 63.6951 21,216 149,460 13,757 64,163 8,660 95,316 9,391 35,822 1,576 1,810 4,201 16,533 1,28
1982 60.972 18,860 142,519 16,919 105,961 16,822 136,153 16,664 46,266 10,521 13,491 6,843 128,015 2,20
1983 56.89il 20,235 141,663 16,500 41,264 4,656 81,935 8,425 51,094 12,420 11,043
5,233 170,799 5,53
Average 61,53 18,211 132,908 16,000 even-134,413 even-42,954 103,774 13,157 37,294 7,943 12,149 6,797 112,869 2,1;
odd-58,264 odd-8,611
Source:MILLS 979,1980,1981,1982,1983,1984
Source:ADF&G 1985b
TABLE E.3.2.6:ESCAPEMENTS BY SPECIES AND
SAMPLING LOCATIONS FOR 1981-84
1/Escapement estimates were derived from tag/recapture population estimates
except Yentna Station escapements which were obtained using sidescan sonar.
Z/second run sockeye salmon escapements only.
~/Chinook salmon were not monitored for escapement.
!±/Yentna Station side scan sonar equipment was not operational on the dates
required to estimate the totai Yentna River chinook salmon escapements for
1981-84.
1981 1/
1982 52,900
1983 90,100
1984'121,700
1
J
1
1
J
I
[
.j
---1
I
1
}
\
1
1
I
I
I
1
31,200
141,200
80,900
325,800
18,000
103,200
39;000-
190,000
212,300
623,000
184,800
56J,400
TOTAL
465,700
1,123,700
483,100
2,128,500
5,238,500
Coho
3,300
5,100
2,400
11,800
17,000
34,.100
8,900
18,200
19,800
45,700
15,200
94,700
190,100
1,100-'--2,400
-800--
2,220
Chum
19,800
27,800
10,800
26,500
20,800
49,100
50,400
98,200
13,100
29;400
21;100
49,300
812,700
262,900
430,400
265,800
765,000
pink
Escapement 1.1
2,300
73,000
9,500
177,900
36,100
447,300
60,700
369,300
49,500
443,200
40,500
1,017,000
3,629,900
2,800 1,000
C30·0 ·-S8,80a
1;900-----S;500
3,600 116,900
4,800
3,100
4,200
13,100
133,500
151,500
71 ,500
130,100
139,400
113,800
104,400
149,400
sockeyel/
605,800
!±/
1/
1/
10,900
14,400
24,800
1/
IT,30b
-9-;700-
18,000
Chinook
1981
1982
1983
1984
1981
1982
1983
1984
1981
1982
1983
1984
Year
1984
Sunshine
Station
Curry
-'Station
Talkeetna
Station
Yentna
Station
Flathorn
Station
Sampling
Location
I I
I J
j
TABLE E.3.2.7:ANALYSIS OF CHINOOK SAlM)N AGE DATA BY PERCENT FRCM ESCAPEMENr
SAMPIES COLlEClED lJ.SEVERAL SUSITNA RIVER STATIONS
1981
Sample
Age Class lJ
Collection Site Size 31 32 41 42 51 52 61 62 72
Susitna Station 33 3.3 36.1 -39.4 -12.1 -9.1 -Yentna Station 37 -18.9 -40.5 -13.5 -27.1 -Sunshine Station 414 2.0 25.6 1.4 30.5 1.2 21~8 0.3 16.6 0.5
Talkeetna Station 70 3.1 12.6 2.6 27.1 -21.4 5.6 24.4 2.9
Curry Station 227 3.7 14.8 4.5 29.8 2.1 25.7 1.4 18.0 -
1982
Age Class lJ
,
SBf!lPle
Collection Site Size 31 32 41 '+2 51 52 62 72
Susitna Station 10 -40.0 -40.0 -10.0 10.0 -Yentna Station 67 -43.3 -29.9 -14.9 11.9 -Sunshine Station 1351 0.2 14.8 0.2 27.2 0.4 20.5 36.1 0.4
Talkeetna Station 358 0.6 20.1 0.6 35.2 1.1 19.5 22.3 0.6
Curry Station 441 1.1 15.9 0.8 28.5 2.5 20.0 30.8 0.5
1983
SBf!lPle
Age Class lJ
Collection Site Size 31 32 41 42 51 52 62 72
Yentna Statwn 15 -33.3 -13.3 -13.3 26.7 13.3
Sunshine Station 1307 -1.5 -3.9 0.1 38.9 45.0 10.6
Talkeetna Station 664 1.4 21.1 0.2 9.2 1.1 32.9 27.9 6.2
Curry Station 712 0.3 9.1 -3.9 -24.4 43.5 18.8
1984
Sample
Age Class lJ
Collection Site Size 31 32 41 42 43 51 52 61 62 71 72
F1athom Station 30 -56.7 -16.7 --16.7 -10.0 --
Yentna Station 13 -7.7 -38.5 --7.7 -46.2 --Sunshine Station 1245 0.5 6.6 0.2 4.9 0.1 0.2 18.0 0.5 44.3 0.1 24.7
Talkeetna Station 652 0.2 0.9 0.6 4.3 -0.3 17.5 0.6 47.1 -28.5
Curry Station 468 0.9 9.8 -6.0 --13.3 -40.6 0.2 29.3
Y Gilbert-Rich Notation.
Source:ADF&G 1981a,1983a,1984h,1985b
TABLE E.3.2.8:CHINOOK SALMON PEAK SURVEY ESCAPEMENT COUNTS
OF SUSITNA RIVER BASIN STREAMS FROM 1976 TO 1984 .
Year
]
1
I
"I
I
I
I
I
4,191
!?/
!?/
·39
!?/
51.!!!
Y
Y
6,138E!
!?/
!?/
__1lJ'
1984
lUE!
1,028
258
2,309
22
1,456
2,341
9,000
·1,520E!
4,620
16,892
2,789
b
1983
297
945
477
1,641
12
1,193
3,140
3,200!¥
806
3,846
!?/
BI---w-
!?/
523
2,272
7,057
10,014
575
!?/
...!?L
1982
U9.!!!
156.!!!
527.!!!
140.!!!
887.!!!
47
1,053
1,253
3,844
·982
2,546 3,755
16,000!!1 19,237
592.!!!777
316.!!!1,042
1981
y 644.!!!
!/100!!!
a/27.!!!
~N--·--7!!!-....
Y 36!!!
!/198
Y !l!/3,577
2,129 3,101
84 !?/
8 !?/
.......7¥l.....-BI
!/y
y !/
!/1,357
!/459
!/557
!/1,013
!/262
!/814
!?/40
!/422
!/659
a/1,900
!/!/
1980
y
!/
af
.-"!/-
y
!/-
y
!/
!/
!?/
!?/.-w
1979
457
778
BI
1,094E!
BI
285
190
il
8649-
6,215
27,385
1,086
324E!
59
1978
362
1,209
283
881
BI
114
140
5,154
997
900 Y
62 !/
13 37
-!/-28-
Y y
!/58
1,335 !/
8,931 4,196
1,375 1,648
BI BI
!?/!?/
.~8~L ..·....··....El.
5,854
24,639
1,661
436
168
1977
336·
630
133
1,443
BI
393
374
5,790
769···
9,246
39,642
1,065
598
112
1976
203
455
160
1,445
BI
537
702
6,513
1,237
5,412
21,693
1,660
883
Stream
Alexander Creek
Deshka River
Willow Creek
Little Willow Creek
Kashwitna Ri ver
(North Fork)
Sheep Creek
Goose Creek
Montana Creek
Lane Creek
Indian River
Portage Creek
Prairie Creek
Clear Creek
Chulitna River
(East Fork)
Chulitna River
(t-F)1,870 1,782
Chulitna Ri ver 124 229
Honolulu Creek 24 36
CBylfl"-S-CrceeM ·------53---~69-
Troublesome Creek 92 95
Bunco Creek U2 136
Petters Creek 2,280 4,102
Lake Creek 3,735 7,391
Talachulitna River 1,319 1,856
Canyon Creek 44 135
Quartz Creek BI 8
---RedCreek___!?/_l,5.U
TOTAL 50,615 77,937 54,790
y No tot~l count due to high turbid water
!?/Not counted
E!Poor counting condit~ons
.!!!Counts conducted after peak spawning
!¥EstimatedpeEikspawning count
Source:ADF&G 1981a, 1983a,1984h,1985b
I
1
I
1
I
I
1
J
TABLE E.3.2.10:NUMBER OF FISH,MEAN LENGTH,
AND RANGE OF LENGTHS FOR AGE·0+
CHINOOK SALMON BY SAMPLING PERIOD
ON THE SUSITNA RIVER BETWEEN
TALKEETNA AND DEVIL CANYON
1
I
\
.!/Includes all mainstem,slough,and side channel sites sampled during
.thecoded.wire tagging.andcoldbranding ..s.tudi~sintbeJllidc::lle.:J:"eo!l(,::llC>J:t:lle
...Susitna River.
Source:ADF&G 1983m,1985c
e/Not Sampled.
May 0 60 40.8 35-45
June 1-15 1 40 40 b/
June 16-30 19 49 34-70 'E./
July 1-15 67 55 36-74 100 47.8 38..;..67
July 16-31 139 154 36-77 50 52.2 42-69
August 1-15 84 161 39-88 50 52.4 .".40-77
August 16-31 65 64 42-94 100 56.1 43-72
September 1-15 100 69 41-95 100 57.6 47-88
September 15 -October 15 42 69 47-100 200 61.0 45-90 50-89
]
\
Range
(mm)I
I
1
47-90
49-80 1
1
I
!
I
I
I
j
j
I.,
42-64
47-67.:-)
47-90
Mean
(mm)
Mainstem
Indian River
~/
~/
~/
50 48.9
50 54.9
100 58.8
100 61.1
100 63.8
No.
300 65.5
Range
(mm)
Mean
(mm)
1984
Mainstem
Susitna River.!/
No.Rang.e
(mm)
1982
Mean
(mm)
Mainstem
Susitna River
No.Sampling
Period
TABlE E.3.2.11:ANALYSIS OF SOCKEYE SAI.MJN
PnE Il!\TA BY PERCENI FROM.ESCAPOONI'
SAMPlES <XJIJ..F.GIED AT.SEVERAL SUSTINA.
RIVER STATIONS
1981
Sai!Jple
Age Class JJ
Collection Site Size 31 32 41 42 43 51 52 53 62 63
Susitna Station 1709 0.0 0.6 0.0
8.4 0.0 0.0 83.9 2.7 0.1 4.3
Yentna Station 1193 0.1 0.7 0.7 7.5 0.4 1.9 80.0 3.5 2.4 2.0
Sunshine Station 976 0.0 1.1 0.6 21,,0 0.6 0.0 70.2 2.6 0.2 3.7
Talkeetna Station 110 0.0 0.0 1.8 22.8 0.0 0.0 70.2 1.8 1.8 1.8
Curry Station 270 0.0 0.7 1.1 27.4 0.0 0.0 65.9 3.4 0.0 1.5.
1982
.Age Class Jj
Collection Site SaI!lPle
31 32 41 42 51 52 -;,61 62 7I hSize43
Susitna Station 996 0.1 0.4 0.1 22.4 0.2 '0.1 65.8 2.1 -8.8 -Yentna Station 708 0.4 3.5 0.4 27.7 0.4 -52.7 4.0 0.6 10.3 -Sunshine Station -- --- - -
--- -
First Run 314 ---6.4 --89.5 --4.1 -Second Run 648 0.3 2.8 1.2 22.1 0.5 _;,1 69.8 0.9 0.3 2.0 0.2
Talkeetna Station 373 -4.3 -21.2 2.1 -70.8 0.8 -0.8 -
Curry Station 105 1.0 21.9 .-:-;t.30.5 9.5 -32.4 4.8 -- -
1983
Sai!Jple
Age Class JJ
Collection Site Size 31 32 41 42 43 51 52 53 62 63
Yentna Station 1024 0.4 4.7 0.4 66.8 0.9 0.5 22.6 1.8 0.2 1.7
Sunshine Station .
First Run 290 - -
-26.9 --71.4 0.7 1.0 -
Second Run 994 0.1 -0.1 63.4 0.5 0.1 33.7 1.7 -0.4
Talkeetna Station 344 0.3 4.1 -50.9 4.9 -38.1 1.7 --
Curry Station
1984
SaI!lPle
Age Class JJ
Collecticn Site Size 31 32 41 42 43 51 52 61 62 7I 72
Flathom Station 1780 1.0 5.8 -1.5 43.3 1.1 1.0 40.3 4.4 0.1 1.4
Yentoa.Station 2253 0.2 1.3 -1.6 23.7 0.3 -59.7 6.5 0.1 6.7
Sunshine Station
First Run 365 -- -
0.3 3.0 -0.3 96.2 -0.3 -
Second Run 970 0.8 3.3 0.1 2.2 59.3 1.0 -29.3 3.3 -0.7
Talkeetna Station 452 0.7 0.4 4.4 79.0 0.4 0.4 12.6 1.5 -0.4-
Curry Station 212 1.9 1.9 -3.8 65.1 3.8 0.5 16.5 5.7 0.5 0.5
11 Gi]bert-Rich Notation.
Source:ADF&G 1981a, 1983a,19841:1,1985b
TABLE E.3.2.12:ESTIMATED SOCKEYE SALMON ESCAPEMENTS TO SLOUGHS ABOVE RIVERMILE 98.6
1981 1982
%Curry %Curry %Curry %Curry
Slough River Slough Station Slough Station Slough Station Slough Station
Mile Escapement Escapement Escapement Escapement Escapement Escapement Escapement Escapement
1 99.6 0 0 0 0 0 0 26 0.8
2 .100.2 0 0 0 0 0 0 18 0.6
3B 101.4 0 0 0 0 10 0.5 36 1.1
3A 101.9 13 0.5 0 0 0 0 29 0.9
5 107.6 0 0 0 0 0 0 3 0.1
8 113.7 0 0 0 0 0 0 5 0.2
8C 121.9 0 0 5 0.4 0 0 0 0
8B 122.2 0 0 13 ~.1.0 0 0 0 0
Moose 123.5 0 0 20 1.5 31 106 0 0
8A 125.1 195 7.0 131 10.1 130 6.8 532 16.6
B 126.3 !J -20 1.5 10 0.5 23 0.7
9 128.3 18 0.6 13 1.0 0 0 16 0:"5
9B 129.2 212 7.6 0 0 0 0 18 0.6
9A 133.8 4 0.1 0 0 0 0 0 0
11 135.3 1,620 57.9 1,199 92.2 564 .29.7 1,280 40.0
15 137.2 0 0 0 0 0 0 3 0.1
17 138.9 11 0.4 0 0 11 0.6 26 0.8
19 139.7 42 1.5 0 0 10 0.5 29 0.9
21 .·141-~1 &3 2~3 87~-6.7 294 15S 154 4~8
22 144.5 Y -Y -0 0 5 0.2
Y Not Survyed
Source:ADF&G1984h,1985b
1
I
I
I
.!
]
TABLE E.3.2.13 :SUMMARY OF LENGTHS OF AGE S 0+AND 1+JUVENILE
SOCKEYE SALMON BY SAMPLING PERIOD DURING 1984
Lengths of Age 0+Sockeye
May 213 32.0 26-41
June 1-15 305 36.5 28-60
June 16-30 509 41.9 25-71
July 1-15 570 48.8 30-75
July 16-31 748 53.4 35-87
August 1-15 547 51.8 33-88
August 16-31 90 58.6 42-79
September 1...:15 95 59.8 40-91
September 16 thru
October 15 15 60.4 48-90
Sampling Period n
At Talkeetna
Mean Range
(mm)(mm)
At Flathorn
n Mean Range
(mm)(mm)
134 32.8 27-45
284 40.4 29'"':'.60
343 42.7 25-70
313 49.2 25-80
337 52.2 30-85
239 53.0 29-85
185 52.8 30-93
41 55.6 42-75
37 57.2 38-81
Length of Age 1+Sockeye
Devil Canyon to Cook Inlet
n Mean Range
(mm)(mm)
May
June 1-15
June 16-30
July
32 71.3
40 71.3
15 77.8
3 91.7
56-99
61-100
71-91
81-102
II
Source:ADF&G 1985c
TABLE E.3.2.14:ANALYSIS OF COHO SALMON
AGE DATA BY PERCENT FROM ESCAPEMENT
SAMPLES COLLECTED AT SEVERAL SUSITNA
RIVER STATIONS
1981
Age Class l/
Sample
Collection Site Size 31 32 33 42 43 44 52 54
Susitna Station 224 0.0 22.0 0.4 0.9 68.8 1.3 0.0 6.6
Yentna station 323 0.0 16.1 0.0 0.0 82.9 0.0 0.0 1.0
Sunshine Station 424 0.0 31.8 0.0 0.0 65.1 0.0 0.0 3.1
Talkeetna Station 164 0.0 11.6 0.6 0.0 84.8 0.0 1.2 1.8
Curry Station 77 1.3 27.3 0.0 0.0 68.8 0.0 0.0 2.6
1982
Age Class l/
Sample
Collection Site Size 32 33 .42 43 44 54
Yentna Station 311 14.5 1.6 0.3 79.1 1.0 3.5
Sunshine Station 516 35.9 -0.2 63.1 -0.8
Talkeetna Station 231 39.4 -0.4 60.2 --Curry Station ;
1983
Age Class l/
Sample
Collection Site Size 32 43 44 54
--SusJ:fila .--299-,'33-;;-8---_..-~_..........._,_..-64-.-o--~-'I~-'-1;7 1---Yentna Station 422 31.8 66.8 -1.4
Sunshine Station 342 49.3 50.1 0.3 0.3
Talkeetna Station 212 59.0 41.0 --
C.urry Station 98 54.0 46.0 --
,1984
Age Class l/
Sample
Collection Site Size 31 32 33 42 43 44 52 54
S.usitna~S.tation~______8A2._~__O_.lL.___.31_.A.___.___~.2.---__.Q...i_~_61.9 2.4 1.1 0.4
377 27.9 --69.5 -----0.5----_.--z.-r------,~....-----,--1-Yentna Station ---Sunshine Station 562 -34.2 -0.2 64.2 -1.4 -Talkeetna Station 309 -31.7 --67.3 -1.0 -
Curry Station 166 -46.4 --51.8 0.6 1.2 -
11 Gilbert-Rich Notation.
Source:AFD&G 1981a,19838,1984h,1985b
'j
'.!
I
!.
Sampling Number of Mean Range of
Period Fish Length Lengths
May 5 133.2 120-1fjO
June 1 -15 7 135.6 114""'157
June 16 -30 1 136.0 136
July 1 -15 2 130.0 130
July 16 -31 0
August 1 -15 1 126.0 126
August 16 -31 13 138.0 125-176
September 1 -15 2 134.0 134
Sep.16 -Oct.15 13 141.0 135-150
*From Cook Inlet to Devil Canyon
Source:ADF&G 1985c
1
I
I
1
1
I
,1
I
j
I
!
I
!
I
I
]
!
1
1
I
I j
TABLE E.3.2.17:ANALYSIS OF CHUM SALMON AGE DATA BY PERCENT FROM ESCAPEMENT
SAMPLES COLLECTED AT SEVERAL SUSITNA RIVER STATIONS
1981
Age classl/
Collection Site Sample Size 31 41 51
Susitna Station 158 3.2 88.6 8.2
Yentna Station 754 6.6 84.1 9.3
Sunshine Station 1088 4.1 88.7 7.2
Talkeetna Station 438 4.1 85.2 10.7
Curry Station 632 1.9 84.0 14.1
1982
Age classl/
Collection Site Sample Size 31 41 51 61
Yentna Station 553 2.2 88.6 51.3 0.4
Sunshine Station 1043 0.3 40.1 58.4 1.2
Talkeetna Station 620 0.8 30.3 68.7 0.2 -Curry Station -,456 0.8 30.3 72.1 ---
1983
Age classl/
Collection Site Sample Size 31 41 51
Susitna Station 333 4.5 84.4 11.1
Yentna Station 629 3.3 90.3 6.3
Sunshine Station 906 5.5 91.1 3.4
Talkeetna Station 526 4.9 87.1 8.0
Curry Station 480 2.1 85.8 12.1
1984
Age classl/
Collection Site Sample Size 21 31 41 51 61
Flathorn Station 1363 -----15.5 73.9 10.2 0.4---
Yentna Station 702 0.1 19.7 69.2 10.2 0.7
Sunshine Station 711 ---6.5 69.2 22.9 1.4
Curry Station 576 ---10.4 7.11 16.7 1.9
1/Gilbert-Rich Notation
Source:ADF&G 1981a,1983a,1984h,1985b.
TABLE E.3.2.18:CHUM SALMON PEAK ESCAPEMENT
COUNTS FOR TRIBUTARY STREAMS
ABOVE RIVER MILE 98.6
Source:ADF&G 1981a,1983a,1984h,1985b
Peak Count
Stream
Whiskers Creek
Chase Creek
Lane Creek
Little McKenzie Creek
Little Portage Creek
5th of July Creek
Skull Creek
Sherman Creek
4th of July Creek
Indian River
Jack -liongCreek
Portage Creek
River
Mile
101.4
106.9
113.6
116.2
117.7
123.7
124.7
130.8
131.1
138.6
144 ..5 -
148.9
1981
1
1
76
14
o
o
10
9
90
40
o
o
1982
o
o
11
o
31
1
1
o
191
1,346
153
1983
o
o
6
1
6
o
o
148
811
526
1984
o
1
31
23
18
2
4
6
193
2,447
-4
1,285
]
I
1
-)
"]
]
ill
J
J
I
I
I
I
l
I
;.1
1
]
1
II
t ,
11
11
TABLE E.3.2.19:ESTIMATED CHUM SALMON ESCAPEMENTS TO SLOUGHS ABOVE RIVER MILE 98.6
1982
%Curry %Curry %Curry %Curry
Slough River Slough Station Slough Station Slough Station Slough S~ation
Mile Escapement Escapement Escapement Escapement Escapement Escapement Escapement Escapement
1 99.6 10 0.1 0 0 0 0 46 0.1
2 100.2 43 0.3 0 0 96 0.5 188 0.4
3B 101.4 0 0 0 0 0 0 109 0.2
6A 112.3 19 0.2 5 <0.1 0 0 0 0
8 113.7 695 5.3 0 0 0 0 217 0.4
Bushrod 117.8 Y Y Y Y Y ]!/161 0.3
8D 121.8 0 0 53 0.2 0 0 60 0.1
8C 121.9 0 0 108 0.4 8 0.1 207 0.4
8B 122.2 0 0 99 0.3 261 ;1.2 860 1.7
Moose 123.5 222 1.7 59 0.2 86 0.4 284 0.6
Al 124.6 200 1.5 0 0 155 0.7 217 0.4
A 124.7 81 0.6 0 0 4 <0.1 8 0.1
8A 125.1 480 3.7 1,062 3.6 112 0.5 2,383 4.8
8B 126.3 Y Y 104 0.4 14 0.1 168 0.3
9 128.3 368 2.8 :;603 2.1 430 2.0 304 0.6
9B 129.2 277 2.1 12 0.1 0 0 132 0.3
9A 133.8 140 1.1 86 0.3 231 1.1 528 1.1
10 133.8 0 0 0 0 0 0 90 0.2
11 135.3 1,119 8.5 1,078 3.7 674 3.2 3,418 6.9
13 135.9 7 0.1 0 0 8 0.1 16 0.1
14 135.9 0 0 0 0 0 0 4 0.1
15 137.2 0 0 0 0 4 <0.1 67 0.1
16 137.3 5 <0.1 0 0 0 0 20 0.1
17 138.9 135 1.0 23 0.1 166 0.8 204 0.4
18 139.1 0 0 0 0 0 0 42 0.1
19 139.7 5 <0.1 0 0 6 <0.1 102 0.2
20 140.0 24 0.2 28 0.1 103 0.5 329 0.7
21 141.1 657 5.0 1,737 5.9 481 2.3 4,245 8.6
22 144.5 Y Y Y Y 105 0.5 187 0.4
21A 145.3 14 0.1 0 0 0 0 38 0.1
!I Not Surveyed
Source:ADf&G 1984h,1985b
TABLE E.3.2.20:PINK SALMON PEAK ESCAPEMENT
COUNTS FOR TRIBUTARY STREAMS
ABOVE RIVER MILE 98.6
Peak Count
River
Whiskers Creek 101.4
Chase Creek 106.9
Slash Creek 111.2
Gash Creek 111.6
Lane Creek 113.6
Clyde Creek 113.8
Maggot Creek 115.6
Little McKenzie Creek 116.2
McKenzie Creek 116.7
Little Portage Creek 117.7
Fr~~I!~~Q:t'ee~.119.3
Downunda Creek 119.4
Dead Horse Creek 120.8
Tulip Creek 120.9
5th of July Creek 123.7
Skull Creek 124.7
·········ShermancCreek ··130·0·8·
4th of-July Creek-·-·-·-T31 :T·----.
Gold Creek 136.7
Indian River 138.6
Jack Long Creek 144.5
Portage Creek 148~9
Stream Mile 1981 1982
1 138
38 107
1/0
0 640
291 0
1/1/
1/1
0 23
0 17
1/140
1/1/
1/ 1/
0 1/
1/ 1/
2 113
8 12
············6 ·······24
····~f9·--..-·--··-70-2--
0 11
2 738
1 21
0 169
1983
o
6
o
o
28
17
o
7
9
1
··0
·----·78-
7
886
5
285
1/Not Surveyed
Source:ADF&G 1981a,1983a,1984h,1985b
TABLE E.3.2.21:FISH SPECIES INHABITING STREAMS WITHIN (Page 1 of 3)
THE ACCESS AND TRANSMISSION LINE CORRIDORS
Stream Number
and/or Name Date
Species
Observed
Number
Captured
Range
(mm)
Denali High to Watana
1 1/830817
2 -Lily Creek 830817
3 -Seattle Creek 830817
4 830817
Dolly Varden 9
Sculpin 1
Dolly Varden 10
Sculpin 2
Dolly Varden 50
Arctic grayling 9
Sculpin 3
Dolly Varden 3
85 -150
70
105 -190
60 -85
70 -195
100 -310
70 -95
80 -125
I
IJ
5
6
7
8 -Brushkana
Creek
9
10
11
12 -Deadman
creek
13
830817
830818 .
830818
830818
830818
830818
830818
830818
830813
NONE
NONE
a
Arctic grayling 3
Sculpin 2
Arctic grayling 9
Sculpin 10
Dolly Varden 30
Arctic grayling 20
Sculpin 10
a
Arctic grayling 3
Sculpin
a
350 -385
80 -95
60 -380
60 -95
90 -205
95 -285
80 -95
240 -365
50 -95
a -did not sample
1/Location of numbered streams identified in Figures E.3.2.14 thru 17.
TABLE E.3.2.21 (Page 3 of 3)
Length
Stream Number Species Number Range
and/or Name Date Observed Captured (mm)
Watana to Devil Canyon
28 831815 Dolly Varden 1 105
Sculpin 1 65
29 830815 Dolly Varden 1 80 -100
Sculpin 1 65
11
30 830815 a
31 830815 Dolly Varden 20 90 -190
Sculpin 6 50 -90
']I ,32 830815 Dolly Varden 15 150 -375
Sculpin 2 60 -80
33 830815 Sculpin 1 65
34 -Devil Creek 830815 Sculpin 2 75 -80
35 830815 Dolly Varden 1 155
Sculpin 1 65
36 830815 Dolly Varden 1 140
Devil Canyon to Gold Creek
37 830813 Sculpin 1 60
38 830816 a
39 830816 a
40 830816 Chinook salmon 20 40 -60
Sculpin 3 50 -95
41 -Waterfall
Creek 831816 Arctic grayling 1 140
Chinook salmon 30 40 -60
Sculpin 8 40 -85
42 -Gold Creek 830816 a
a -did not sample
TABLE E.3.2.22:FISH SPECIES INHABITING LAKES WITHIN THE
ACCESS AND TRANSMISSION LINE CORRIDORS
Length
Species Number Range
Lake Geographic Code Date Observed Capj:ured (mm)
Ridge Lake F 22S 05W 25 DCA 830917 a
Beaver Lake S 33N 05W 34 DDC 830917 Burbot 1 275
Arctic grayling 3 260 -335
Sculpin 3 65 -90
Long Lake S 32N 05W 15 CAC 830915 Sculpin 1 85
Round Lake S 32N 05W 15 CCC 830915 NONE
Swimming Bear
Lake S 32N 07W 04 BAa 830916 Dolly Varden 13 125 -380
Sculpin 7 65 -95
High Lake S 32N 02E 20 DBB 830918 Rainbow Trout 15 160 - 430
Sculpin 2 60 -85
Little High
Lake S 32N 02E 19 MC 830918 Rainbow Trout 7 160 -285
Sculpin I 65
IslandL-ake-.S :32NOIE -25 ABD--8309-18--Do By Varden .-20 300-445
Sculpin 2 65 -95
Highest Lake S 32N OlE 14 ADD 830920 Dolly Varden 7 115 -245
Sculpin 1 75
Source:ADF&G
-1
,]
-\
]
1
)
~1
1
1
]
1
I
1
]
I
I
1
I
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TABLE E.3.2.23:ARCTIC GRAYLING HOOK AND LINE
CATCH IN TRIBUTARIES WITHIN
THE IMPOUNDMENT ZONE BY
LOCATION AND MONTH
1981 CATCH
Tributary May June July August September Total
Oshetna River 19 92 155 73 167 506
Goose Creek 121 136 82 37 6 382
Jay Creek 3 178 70 16 50 317
Kosina Creek 136 246 143 67 i87 779
Watana Creek 1 49 16 172 28 266
Deadman Creek 53 86 42 6 3 190
j Tsusena Creek 23 19 74 18 1 135
Fog Creek 22 17 23 5 5 72
TOTAL CATCH 378 823 605 394 447 2,647
1982 CATCH
Tributary
May June July August September Total
Oshetna River 10 288 243 172 713
Goose Creek 38 91 76 2 207
Jay Creek 3 79 130 108 4 324
Kosina Crek 37 232 491 604 320 1,684
Watana Creek 128 175 208 36 547
Deadman Creek 40 51 110 1 203
IJ Tsusena Creek 7 10 29 26 7 79
Fog Creek 1 5 17 2 25
TOTAL CATCH 58 528 1,260 1,392 544 3,782
Source:·ADF&G 1981£,1983b
TABLE E.3.2.24:ARCTIC GRAYLING POPULATION ESTIMATES FOR THE
REACH OF MAJOR TRIBUTARIES IN THE WATANA AND
DEVIL CANYON IMPOUNDMENT AREAS
Petersen
Population Estimatell
1982
1982l/Number
Stream Reservoir 1981.U Number per mile
Oshetna River Watana 2,017 2,426 1,103
Goose Creek Watana 1,327 949 791
Jay Creek Watana 1,089 1,592 455
Kosina Creek Watana 2,787 5,544 1,232
Watana Creek Watana 3,925 323
Deadman Creek Watana 979 734 1,835
Tsusena Creek Devil Canyon 1,000 ..440
Fog Creek Devil Canyon 176 664
II Estimates for·tributary reaches below El.2135 ft.MSL in Watana
Reservoir a.rea and below El.1455 MSL in Devil Canyon Reservoir.
2..1 1981 Estimate based "on Arctic grayling greater than 8 inches
(200 mm)long.
JJ 1982 Estimate based on all ages,but underestimates ages 1 and 2.
Source:ADF&G 1983b
't
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1
j
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I
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j
-j
)
J
.J
TABLE E.3.2.25:PETERSEN POPULATION ESTIMATE FOR
ARCTIC GRAYLING BY AGE GROUP IN THE
WATANA IMPOUNDMENT AREA,SUMMER 1982
Number Number Number Estimated Number
Age Marked Recaptured Caught in Age Group
1 & 2 91 3 84 1,955
3 226 10 222 4,602
4 263 23 263 2,904
5 321 44 342 2,454
6 204 48 270 1,134
7 81 16 107 521
7 and
above 27 7 41 180
Totals 1,281 153 1,337 13,750
Source:ADF&G 1983b
TABLE E.3.2.26:SUSITNA HYDROELECTRIC PROJECT INFLUENCE
OF MAIN STEM FLOW AND WATER QUALITY ON .
CHARACTERISTICS OF AQUATIC HABITAT TYPES
Physical Characteristics
Habitat Type .Hydraulicll Hydrologic Temp.Turbidity Ice Total
Mainstem (MS)4 4 4 4 4 20
Side Channel (SC)3 4 4 3 4 18
Tributary Mouth (TM)3 3 2 2 3 13
Side Slough (SS)2 2 2 2 2 10
Upland Slough (US)1 1 0 0 0 2
Tributary (T)0 0 0 0 0 0
Lake (L)0 0 0 0 0 0
o -no influence
1 -small,limited influence
2 -moderate,occasional influence
3 -moderate,frequent influence
4 direct,extensive influence
II Depth,velocity,wetted area,etc.
Source:HE 1985a
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TABLE E.3.2.27:SUSITNA HYDROELECTRIC PROJECT LOCATIONS
OF NAMED TRIBUTARIES OF THE SUSITNA RIVER
IN THE RESERVOIR AREA
Tributary Susitna River
11
Confluence
(River Mile)
Oshetna River 233.4
Goose Creek 231.3
Jay Creek 208.5
Kosina Creek 206.8
Watana Creek 194.1
Deadman Creek 186.7
Tsusena Creek 181.3
Fog Creek 176.7
Devil Creek 161.4
Chinook Creek 157.0
Cheechako Greek 152.4
Source:ADF&G 1983d
TABLE E.3.2.29:TOTAL SURFACE AREAS BY HABITAT TYPE WITHIN-THE
TALKEETNA-DEVIL CANYON REACH OF THE SUSITNA RIVER
Surface Area (acres)by Discharge
5,100 7,400 10,600 12,500 16,000 18,000 23,000
Habitat Type cfs cfs cfs cfs cfs cfs cfs
Mainstem 2,458.1 2,599.6 2,805.9 2,850.4 3,158.5 Data 3,737.2
Side Channel 729.7 768.7 968.7 1,095.5 1,222.2 not 1,240.7
Side Slough 121.4 144.0 134.2 118.1 85.8 Avail-52.5
Upland Slough 15.3 22.9 19.6 23.6 22.6.able at 24.4
Tributary Mouth 15.9 15.1 18.6 26.2 25.3 Time of 12.1
Gravel Bar 2,518.5 2,301.2 1,848.4 1,727.7 1,419.2 Publi-815.8
Vegetated Bar 1,945.4 2,130.5 2,080.2 1,919.1 2,011.4 cation 1,718.4
Source:EWT&A 1985b
TABLE E.3.2.30:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP I
Description:Habitat character is dominated by high breaching flow
(40,000 cfs).This group includes all upland sloughs and Slough 11
(RM 135.6R).Specific area hydraulics are characterized by pooled
clear water wi th veloci ties frequently near zero and depths greater
than 1 ft.Pooled areas are commonly connected by short riffles where
velocities are less than 1 fps and depths are less than 0.5 feet.
Source:EWT&A and AEIDC 1985
RJHAB =ADF&G Habitat Model
~':':"':':":::D.ata.not.ayailahl.e
I
~
1
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J
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I
1
1
I
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I
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)
r
Model
RJHAB
RJHAB
U.I:);)
0.64
0.44
0.70
0.68
0.45
0.50
0.83
0.45
0.67
0.58
~;0.44
0.67
0.99
0.~2
0.54
0.69
0.45
0.74 .
Structural
Habitat
Index
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000
>35,000-
>35,000
>35,000
>35,000
>35,000
Breaching
Flow
(cfs)
Slough 10
Slough 12
Slough 11
Slough 6A
Slough 5
Known As
102.2L
105.2R
107.6L
108.3L
112.5L
119.4L
120.0R
121.9R
123.1R
123.3R
127.2M
129.4R
133.9L
134.0L
135.5
135.6R
136.9R
139.0L
139.9R
Specific
Area
TABLE E.3.2.31:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP II
Description:Habitat character is dominated by relatively high breach-
ing flows (20,000 -40,000 cfs)and the presence of upwelling ground water
sources that persist throughout winter.This group includes the specific
areas that are commonly called sloughs.These specific areas typically
have relatively large channel length to width ratios.
Specific
Area
100.6R
101.4L
101.8L
113.1R
113.7R
115.6R
117.9L
118.0L
121.8R
122.4R
122.5R
123.6R
125.1R
125.9R
126.0R
126.3R
131.8L
133.9R
135.3L
137.5R
137.5L
137.8L
137.9L
140.2R
142.1R
142.2R
143.4L
144.4L
Known As
Slough 3B
Slough 8
Slough 8D
Slough 8B
Moose Slough
Slough 8A
Slough B
Slough 22
Breaching
Flow
(cfs)
33,000
22,000
22,000
26,000
24,000
23,000
22,000
22,000
22,000
26,000
20,000
25,500
20,000
26,000
33,000
27,000
26,900
30,000
23,000
22,000
29,000
20,000
21,000
26,500
23,000
32,000
30,000
21,000
Structural
Habitat
Index
0.60
0.54
0.60
0.43
0.51
0.54
0.62
0.39
0.27
0.29
0.51
0.43
0.48
0.56
0.51
0.59
0.45
0.50
0.30
0.44
0.60
0.64
0.50
0.50
0.65
0.52
0.55
0.60
Model
RJHAB
RJHAB
IFG
DIHAB
RJHAB
IJ
DIHAB =EWT&A Direct Input Model
IFG =Instream Flow Group Habitat Model
RJHAB =ADF&G Habitat Model
--=Data not available
Source:EWT&A and AEIDC 1985
TABLE E.3.2.32:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP III .
]
j
Description:Habitat character is dominated by intermediate breaching flows
(5,100 cfs -20000 cfs)and relatively broad channel sections.This group
includes side channels which become nonbreached at intermediate lIiainstem discharge
levels and transform into slough habitat at lower discharges.Breaching flows are
typically lower than for Group II,upwelling is present and the length to width:]
ratios of the channels are genera lly less than ratios for Group II.
Specific
Area Known As
Breaching
Flow
(cfs)
Structural
Habitat
Index Model
Source:EWT&A and AEIDC 1985
DlHAB =Direct Input Model Developed by EWT&A
lEG:::Ins tream.Flow-..Group..Ha b itat..ModeL.._.
..RJHAR.=.AIlF..&.G....Hg..Ql..tat Model...............~_...._.._...
--=Data Not Available
Slough 9
Side Channel 21
I
I
J
IFG
IFG
DIHAB
IFG
DIHAB
DlHAB
~-lFG,RJHAB
DIHAB
0.51
0.48
'0.56
0.61
0.46
0.67
0.55
0.48
0.56
0.48
0.49
0.34
0.64
0.60
0~49
0.44
0.49
0.56
12,500
9,200
9,200
14,000
9,600
12,000
12,000
8,000
16,000
10,400
15,000
16,000
8,200
12,000
10;-500
11,500
10,400
11,500
Whisker's Creek Side Channel
Lower Whisker's Creek Side Channel
Upper Whisker's Creek Side Channel
Oxbow V
Mainstem II
Curry Side Channel 21
Oxbow II Side Channel
Side Channel 9
lOO.4R
100.6L
lO1.2R
101.6L
101.7L
110.4L
U5.0R
117.8L
119.3L
128.5R
128.7R
128.8R
130.2L
130.2R
'132";'6L'Si:aeCnant1et"10A~
133.7R
137.2R
141.4R
TABLE E.3.2.33:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP IV
Description:Habitat character is dominated by low breaching flows
(<.5100 cfs)and intermediate mean reach velocities.This group includes
the specific areas that are commonly called side channels.These
specific areas possess mean reach velocities ranging from 2-5 fps at a
mainstem discharge of approximately 10000 cfs.
Breaching Structural
Specific Flow Habitat
Area Known As (cfs)Index Model
I 100.7R <5,000 0.49
108.7L <5,000 0.53
I 1l0.8M <5,000 0.48
111.5R <5,000 0.48
112.6L Side Channel 6A <5,000 0.60 IFG
114.0R <5,000 0.43
116.8R <5,000 0.48
119.5L 5,000 0.54
119.6L <5,000 0.53
121.7R <5,000 0.48
124.1L <5,000 0.46 .,'--
l25.2R Side Channel 8A <5,000 0.61 DIHAB
127.0L <.5,000 0.65 --
127.4L <5,000 0.46
129.5R <5,000 0.56
131.7L 4th of July Creek Side Channel <5,000 0.47 IFG
l34.9R Lower Side Channel <5,000 0.56 IFG
136.0L Doug's Delight Side Channel <5,000 0.55 IFG
l39.4L <5,000 0.61 DIHAB
l39.6L <5,000 0.51
140.4R <5,000 0.48
145.3R <5,000 0.53
IFG =Instream Flow Group Habitat Model
DIHAB =Direct Input Model Developed by EWT&A
--=Data Not Available
Source:EWT&A and AEIDC 1985
IJ
TABLE E.3.2.34:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP V
Description:Habitat character is dominated by channel morphology.This
group includes shoal areas at higher flows··which transform to slough or
clearwater habitats at lower flows as mainstem discharge decreases.
]
.]
Breaching Structural
Specific Flow Habitat
Area Known As (cfs)Index Model
101.7lL 10,000 0.86 DIHAB
117.0M 15,500 0.55
118.9L Lower Little Rock Spawning Site <5,000 0.86 DIHAB
124.0M 23,000 0.91
132.8R 19,500 1.02
139.0L <5,000 0.77 DIHAB
139.7R 22,000 0.91
141.6R Slough 21 21,000 1.00 IFG
143.0L 7,000 0.55 .j
IFG =Instream Flow Group Habitat Model
DIHAB =Direct Input Model Developed by EWT&A
=Data Not Available
Source:EWT&A and AEIDC 1985
TABLE E.3.2.35:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP VI
Description:Habitat character is dominated by channel morphology.
This group includes overvlow channels that parallel the adjacent
mainstem,usually separated by a sparsely vegetated gravel bar.These
specific areas mayor may not possess an upwelling of groundwater
source.
Breaching Structural
Specific Flow Habitat
Area Known As (cfs)Index Model
102.6L 6,500 0.69
106.3R 4,800 0.53
107.1L 9,600 0.69
117.9R 7,300 0.49
119.7L 23,000 0.51
l33.8L Slough 10 Side Channel 17,500 0.49 IFG
135.7R 27,500 0.32
136.3R 13 ,000 0.54 IFG
138.0L 8,000 0.53
138.8R 6,000 0.31
139.5R 8,900 0.31
140.6R 12,000 0.61
142.0R 10,500 0.53
IFG =Instream Flow Group Habitat Model
--=Data Not Available
Source:EWT&A and AEIDC 1985
TABLE E.3.2.36:MIDDLE RIVER HABITAT SITES IN REPRESENTATIvE GROUP VII
Habitat character is dominated by a characteristic
sequence.The Little Rock IFG modeling site (RM 119.2R)is
a riffle just downstream of the side channel head that flows
backwater pool near the mouth.
Description:
riffle/pools
typical with
into a large
Specific
Area Known As
114.1R Lane Creek Spawning Site
119.2R Little Rock Side Channel
121.1L
123.0L
125.6L
127.5M
131.3L
Breaching
Flow
(cfs)
<5,100
10,000
7,400
<5,100
<5,100
<5,100
8,000
Structural
Habitat
Index
0.31
0.41
0.43
'0.39
0.52
0.31
0.31
Model
DIHAB
IFG
DIHAB
1
\
.j
"'l-i~
IFG =Instream Flow Group Habitat Model
DIHAB =Direct Input Model developed by EWT&A
.-No Data Available
Source:EWT&A and AEIDC 1985
••j.'
I
r
I
TABLE E.3.2.37:MIDDLE RIVER HABITAT SITES
IN REPRESENTATIVE GROUP VIII
Description:Habitat character is dominated by the tendency of
these channels to tidewater at a relatively high mainstem
discharge.Channels in this group are frequently oriented with a
30°+angle to the mainstem flowline at their heads.
Specific
Area
101.3M
102.0L
'104.3M
109.5M
112.4L
117.1M
117.2M
118.6M
119.8L
l20.0L
121.5R
121.6R
123.2R
124.8R
125.6R
128.4R
l32.5L
135.0R
l35.1R
140.0M
l45.6R
146.6L
Known As
Breaching
Flow
(cfs)
9,200
10,000
21,000
16,000
22,000
15,500
23,000
14,000
15,500
12,500
19,500
15,500
23,000
19,500
26,000
9,500
14,500
23,000
20,000
22,000
22,000
26,500
Structural
Habitat
Index Model
0.57
0.43
0.48
0.49
0.27
0.32
0.32
0.26
0.51
0.32
0.32
0.60
0.26
0.46
0.54
0.56
0.57
0'.44
0.44
0.31
0.62
0.48
--=No Data Available
Source:EWT&A and AEIDC 1985
Description:Habitat character is dominated by low breaching flows -and rela-
tively swift velocities.This group includes specific areas that were catego-
rized as mainstem at 5100 cfs,as well as side channe1s (Category 5)and
indistinct side channels (Category 6)with mean velocities greater than 5 fps at
10,000 cfs mainstem.
TABLE E.3.2.38:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP IX
Specific
Area Known As
101.5L Whisker's Creek West Side Channel
104.0R
105.7R
108.9L
109.4R
11 I.OR
113.8R
117.7L
127.1M
128.3R
129.3L
129.8R
13I.2R
135.0L
139.2R
141.2R
-141.3R:
142.8R
144.0R
144.2L
147.1L Fat Canoe Island
·IFG =Tnstream Flow Group Habitat Model ..
..-""-=No--Data-Ava-i-lable-.--_-~~--_...-----.
Source:EWT&A and AEIDC 1985
Breaching
Flow
(cfs)
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5,000
<5~bo····.
<5,000·
<5,000
<5,000
<5,000
Structural
Habitat
Index
0.45
0.48
0.53
0.58
0.45
0.35
0.53
0.41
0.53
0.63
0.62
0.56
0.59
0.48
0.61
0.69
0:69
0.56
0.96
0.53
0.57
Model
IFG
IFG I
I
I
J
\
1
J
]
TABLE E.3.2.39:MIDDLE RIVER HABITAT SITES IN REPRESENTATIVE GROUP X
Description:Habitat character is dominated by channel morphology.
This group includes large mainstem shoals,and mainstem margin areas
that had open leads in the March 1983 photography.
Specific
Area Known As
Breaching
Flow
(cfs)
Structural
Habitat
Index Model
105.8lL
109.3M
1l1.6R
113.6R
113.9R
119.11L
l21.1R
133.81R
138.71L
139.3L
l39.41L
l42.8L
l48.2R
MSS
MSS
11,500
10,500
7,000
MSS
MSS
MSS
MSS
MSS
MSS
MSS
MSS
0.57
0.48
0.49
0.55
0.48
0.41
0.47
0.48
0.57
0.56
0.41
0.36
0.48
HAB
HAB
HAB
HAB
HAB
MSS =Mainstem Shoal
HAB =Direct Input Model developed by EWT&A
--=No Data Available
Source:EWT&A and AEIDC 1985
TABLE E.3.2.40:SUSITNA HYDROELECTRIC PROJECT
PRIMARY UTILIZATION OF SENSITIVE HABITAT TYPES
BY EVALUATION SPECIES
s"";spaWiiing/incubati6tl
R -rearing
Habitat Types
Evaluation
Species
Chinook Salmon
Chum Salmon
Coho Salmon
Sockeye Salmon
Pink Salmon ",
Arctic Grayling
Rainbow Trout
Do lly Varden
Burbot
Source:HE 1985a
Mainstem
R
R
R
R
S,R
Side
Channel
R
S
Side
Slough
R
S,R
S,R
Tributary
Mouth
R
R
l
I
j
I
I
·1
!
~\
!
\
I
I
I
i
j
I
1
j
.~--
~ABLE E.3.2.41:COVER ~UITABILITY CRITERIA RECOMMENDED FOR USE IN JUVENILE CHINOOK
HABITAT UNDER CLEAR AND TURBID WATER CONDITIONS
Percent
Cover
No
Cover
Emergent Aquatic Debris &
Veg.Veg.Deadfall
Over Hanging
Riparian
Undercut
Banks
Large
Gravel
Rubble
3"-5
Cobble or
Boulders <5"
Clear Water
0-5%0.01 0.01 0.07 0.11 0.06 0.10 0.07 0.09 0.09
6-25%0.01 0.04 0.22 0.33 0.20 0.32 0.21 0.27 0.29
26-50%0.01 0.07 0.39 0.56 0.34 0.54 0.35 0.45 0.49
51-75%0.01 0.09 0.53 0.78 0.47 0.75 0.49 0.63 0.69
76-100%0.01 0.12 0.68 1.00 0.61 0.97 0.63 0.81 0.89
Turbid Water
0-5%0.31 0.31 0.31 0.48 0.26 0.44 0.31 0.39 0.39
6-25%0.31 0.31 0.39 0.58 0.35 0.56 0.37 0.47 0.51
26-50%0.31 0.31 0.46 0.67 0.41 0.65 0.42 0.54 0.59
51-75%0.31 0.31 0.52 0.77 0.46 0.14 0.48 0.62 0.68
76-100%0.31 0.31 0.58 0.85 0.52 0.82 0.54 0.69 0.76
Sources:ADF&G 1984c,EWT&A and WCC 1985
Table E.3.2 42:JUVENILE CIHNOm~REARING HABITAT AVAILABILITY
AT IFG AND RJI1AB 1'10DELED SITES
Mainstem
Dl scharge
-----------~~----------------r-~----------~-------~---------~-------------------------------------------------
Si~elLocations By Riveri Mile Designation (Representative Group)
I I',
-----------1-------------------~----------------------.------------------------------------
101.2R ~01.4L 101.5L 107.6L 112.5L 112.6L 113.7R 119.2R 126.0R 128.8R
mG 3)Ims 2)(RS 9)(RG 1)(RG 1)ms 4)(RS 2)(RB 7)(RB 2)(RG 3)
-----------~-----------------~-~-----------------~----------------------------------------------------------(cfs)(WUA/1000(WUA11000(WUA/1000 (WLJA/r1000 (WUA/1000(WUA/1000 (WUA/1000(WUA/1000(WUA/1000(WUA/1000
sq.ft.)sb.ft.)sq.f~.)sq.ft.)sq.ft.)sq.ft.)sq.ft.)sq.ft.)sq.ft.) sq.ft.))i ;
4000
5000
6000
7000
8000
90IDID
10ID00
l1QUliID
12IDIlI0
131211l1ID
14IDID0
15IDIDI2I
160ID0
17000
181lJ00
190fl10
20fl100
211210121
22000
23000
2401110
25000
26ID00
27000
28000
29000
3f2112l1210
3101210
32000
33000
3401210
351211210
36012l1ll
37000
38lf.l0121
:3''712l0121
4001210
41000
42000
43000
441210121
45000
0.1210
0.00
0.00
31.66
95.00
158.34
313.71
326.44
271.48
218.77
177.51
147.::)5
121.45
112.39
104.35
97.17
90.73
84.92
79.65
74.85
70.47
66.45
62.75
59.34
56.19
53.26
50.55
48.02
45.66
43.45
41.39
39.45
37.40
35.40
33.30
31.30
29.30
27.20
25.20
23.20
21.10
19.10
'145.25
114$.25
'145.251'~45.25
145.25
i145.25
i145.25
145.25
145.25
145.25
114$.25
:145.25
1
149.25
145.25
1
14.9...25145.25
145.25
1145.25
1
145.25
158.20
1185.'71
1253.70I ,
'322.79134~.47
347.54133~.02
298.34
I '126~.23
246.60II122~.15
215.96II!206.38
QI1I1.20
i181.00
1
161.60
14~.90
130.90
1
'11'1 060
108.70
1101.30
94.2121
87.40
39.00
39.00
41.81l1
43.90
42.80
52.70
49.60
46.60
40.70
41.60
41.50
39.50
37.70
34.10
34.50
36.10
36.10
42.00
43.70
44.7121:
44.80
'45.70
50.60
51.80
52.50
51.70
49.30
47.30
46.60.
44.90
43.20
41.70
40.20
38.50
36.80
35.10
33.40,
31.70
30.00
28.30
26.60
24.90
119.10
118.75
118.49
11:r.86
116.85
115.48
113.76
111.69
109.30
109.60
11l13.61
100.38
96.93
9::;).29
89.48
8S.53
81.34
76.79
72.02
68.17
65.48
58.88
54.00
51.77
56.32
5t·42
57.64
58.01
57,.94
57.88
I57.9 III
5'7..35
57.35
57.35
57.35
56.70
56.70
56.70
56.70
56.1.0
56.10
56.10
41.70
41.70
41.7121
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.7121
41.70
41.70
41.7121
41.70
41.70
41.70
41.70
41.70
41.7121
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41.70
41 •.70
41.70
41.70
41.70
41.70
41.70
317.50
317.50
258.70
227.80
185.9121
144.40
109.00
73.55
55.30
48.80
45.1lI0
50.7121
53.30
53.90
47.50
40.80
35.2121
31.00
27.10
24.70
22.20
20.60
19.10
17.60
16.20
14.80
13.70
12.80
11.90
11.1210
10.90
10.70
10.50
10.3ID
10.10
9.90
9.70
9.50
9.30
9.1121
8.90
8.70
133.40
132.45
131.58
131.36
133.07
136.61
141.60
146.81
152.29
158.46
165.87
176.37
185.92
195.63
204.121121
213.84
224.56
235.08
244.04
251.67
257.72
259.44
267.58
283.56
312.19
360.16
403.44
425.53
424.34
41217.45
387.73
369.38
351.03
332.68
314.33
295.98
277.63
259.28
240.93
222.58
204.23
185.88
.~
185.99
185.99
185.99
185.99
226.21
306.64
387.10
394.50
344.70
353.50
301.80
250.50
199.10
159.20
137.00
111.70
85.60
73.32
63.23
54.72
47.51
43.23
41.17
39.26
37.48
35.82
34.27
32.81
31.45
30.16
28.95
27.80
26.70
25.60
24.50
23.40
22.30
21.20
~~0.10
19.00
17.9121
16.80
.~
176.40
176.40
176.40
176.40
176.4121
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
176.40
242.60
232.60
225.10
217.60
210.10
202.60
195.10
187.60
180.10
172.60
165.10
157.60
15vl.10
20.60
20.60
20.60
20.60
20.60
20.60
20.60
20.60
20.60
20.60
20.60
20.60
20.60
43.90
101.66
263.90
278.80
262.60
242.2121
214.90
169.30
139.90
111.60
83.90
61.40
60.90
60.90
67.90
68.7121
80.70
78.10 '
76.30
74.50
72.70
70.90
69.10
67.30
65.5121
63.70
61.90
60.10
58.30
TABLE E.3.2.42:
I'-----
(CONTINUED)
l'1ainstem
ischarge
(cfs)
Site Locations By River Mile Designation (Representative Group)I
--------------------------~----------------------------------------------------------------1
131.7L 132.6L 133.8L 134.9R '136.0L 136.3R 141.4R 141.6R 144.4L 147.1L I
(RG 4)(RG 3)(RG 6)(RG 4)(RG 4)(RG 6)(RG 3)(RG 5)(RG 2)(RG 9)I
(WUA/1000(WUA/1000(WUA/1000(WUA/1000(WUA/1000(WUA/1000(WUA/1000(WUA/1000(WUA/1000(WUA/1000
sq.ft.)sq.ft.)sq.ft.)sq.ft.)sq.ft.)sq.ft.)sq.ft.)sq.ft.) sq.ft.)sq.ft.)
411I11I11I
511I11I0
611I011I
711I11I11I
80011I
911I11I11I
1011I0121
1111I12111I
1200121
1311I121121
140121121
150121121
1600121
171211210
18000
19011I11I
200121121
210011I
22011I121
2311I11I121
2401210
2511I12111I
2611I00
2711I11I121
280011I
2911I0121
30000
3112100
32000
3312100
3412l012l
35000
3601210
3712100
3812100
391211210
4121000
4112l0fl1
42000
4311I12111I
44000
450011I
278.20
278.2121
298.20
.313.311I
332.6121
328.511I
296.2121
256.8121
2511I.80
2::'~7.611I
215.5121
211I2.4121
187.9121
179.6121
167.3121
158.10
152.11I121
147.92
141.1219
134.611I
128.45
122.59
116.91
111.63
111I6.64
11211.89
97.38
92.19
88.31
84.95
81.73
78.64
76.711I
74.8121
72.911I
71.11I121
69.1121
67.211I
65.3121
63 411I
61 5121
59 6121
0.011I
121.12111I
0.00
37.25
74.5121
111.75
149.00
283.311I
270.9121
262.0121
251.70
243.10
219.60
211I5.8121
18121.8121
151.711I
134.2121
132.90
114.11I121
105.811I
11216.6121
99.1121
91.80
91.2121
92.4121
88.7121
82.70
78.47
75.85
73.37
71.1214
68.84
62.3121
57.7121
54.2121
511I.8121
47.40
45.111I
42.90
4121.7121
38.80
37.121121
111I6.6121
111I6.611I
111I6.611I
11216.6121
11216.6121
111I6.6121
11216.611I
106.6121
111I6.6121
111I6.611I
106.6121
11216.6121
If7.16.6121
11216.6121
192.38
218.2f7.1
213.3121
229.5121
2f7.13.6121
185.6121
150.4121
14121.111I
15121.30
146.121121
132.8121
113.611I
15121.7121
143.1210
126.90
118.1210
11213.5f7.1
95.8f7.1
88.1121
80.40
72.7121
65.1210
57.30
49.60
41.9121
34.20
26.50
18.8121
171.5121
149.121121
126.5121
1011I.2121
11213.8121
81.411I
61.6121
59.4121
45.80
39.7121
32.6121
28.10
26.3121
24.9121
23.7121
21.90
17.5121
17.2121
17.90
18.60
19.2121
19.90
20.5121
211I.70
21.20
21.4121
21.5121
22.7121
23.511I
23.90
24.20
24.30
24.3121
24.4121
24.3121
24.20
24.1121
23.9121
23.8121
23.90
24.00
24.00
287.1121
253.3121
219.5121
184.70
154.111I
131.7121
'110.80
87.11I11I
111.211I
11218.111I
11210.9121
83.80
79.6121
72.40
64.311I
63.811I
71.5121
70.9121
69.70
67.611I
66.2121
64.1121
59.7121
59.1121
58.4121
57.011I
55.70
56.1121
55.211I
54.3121
53.60
53.03
52.4121
51.80
51.::'~121
50.80
50.30
49.711I
49.3121
48.70
48.?121
47.70
106.3121
11216.3121
11216.3121
111I6.30
106.3121
106.3121
106.3121
106.3121
106.30
11216.3121
18121.39
238.47
285.2121
250.5121
256.10
225.1121
21218.8121
196.1121
185.8121
174.30
185.1121
177.90
17121.9121
156.90
154.5121
178.4121
179.7121
179.5121
178.6121
185.11I121
189.3121
J95.20
19121.121121
185.0121
18121.0121
175.00
17121.121121
165.00
160.1210
155.121121
150.121121
145.121121
189.121121
189.00
189.121121
189.0121
189.121121
189.00
184.16
179.75
175.7121
14121.5121
134.20
135.9121
122.50
110.2121
11214.70
88.811I
96.2121
90.5121
81.60
76.311I
76.80
71.50
6121.70
58.911I
56.30
57.70
5~.1II121
55.50
55.411I
55.70
54.6121
54.9121
53.5121
53.11I0
52.121121
51.12111I
50.011I
49.11I11I
48.00
47.11I11I
46.1210
45.00
134.11I11I
134.11I0
134.00
134.11I0
134.11I11I
134.011I
134.12111I
134.11I11I
134.11I11I
134.11I11I
134.011I
134.00
134.11I11I
134.11I11I
134.11I11I
134.11I11I
134.011I
134.11I11I
21211.411I
257.42
304.90
297.711I
280.711I
251.811I
:?1II2.00
166.311I
137.811I
111I6.911I
86.11I0
70.611I
61.1121
57.40
.53.90
50.411I
46.90
43.4121
36.9121
33.411I
29.90
26.411I
22.911I
19.40
35.62
35.62
35.611I
35.54
35.46
35.35
35.21
35.11I3
34.82
34.57
34.29
33.97
33.62
33.23
32.82
32.44
32.75
41.14
90.1217
178.44
241.78
277.11I5
297.4121
287.83
247.84
189.13
14121.18
105.13
77.11I1
58.19
45.53
36.57
27.711I
18.811I
9.90
9.00
8.111I
7.211I
6.311I
5.411I
4.50
3.611I
31.911I
29.411I
26.9121
24.311I
23.80
26.311I
25.40
25.111I
23.30
24.811I
27.60
24.411I
28.011I
24.911I
28.80
3121.5121
29.511I
28.711I
31.30
32.811I
36.11I11I
36.2121
35.7121
35.411I
34.8121
32.211I
32.20
35.411I
34.6121
32.ll11
311I.1121
28.::;11I
26.5121
24.711I
22.9121
21.111I
19.30
17.511I
15.70
13.911I
12.10
10.3121
TABLE E.3.2.431 RESPONSE OF Cl-IUM Sf'At'ININ8 HABITAT AREA IN IF8 AND DIHAB MODELLED SITES
4121121121
512100
600121
7121121121
801210
9000
1001210
11000
12000
1317.100
1417.100
150121121
1601110
1700111
1800121
1912100
2000121
2101210
22000
2300111
24000
2500121
26000
2712100
2812100
29000
31iJ12I0121
311iJ01l1
3201iJ0
33000
341211210
35000
'------'
I .. '.,'I-------------------------T-~-----------------------------------------------------------------------
Whiskers I
I i IMairistemWestSCItIS I I SC Slough 9 4 Jul y SC
~::~~~~~:~~~:~:l_J~~~:~:~~~:~~__L~~~:~~~~~:~:~__~~~:~:~:~::~~:~:~~~~~:~=__
!I ;Gp 3!:Gp 1111 Gp 7 i Gp 3 .'Gp 5 Gp 1121 Gp 4 Gp 3 Gp 7. I !
--------~----------------l-l-----------------~--------------~--------------------------------------
<Cfs)(sq.ft+!(sq.ft.(sq.ft.:(sq.ft.(sq.ft.(sq.ft.(sq.ft.(eq.ft. (eq.ft.
WUAi '.WUA)WUA)I WUA)WUA)WUA)WUA)t'JUA)WUA)
III 121 21216 926 363.,121 121 2367 4~121 .21216 926 444 '121 121 2367 4
~59 21216 926 525 211 667121 2367 4
~117 21216 926 61216 445 14121B2 2367 4
III 2BB 359 112171 677 723 IB622 2367 4o513B3B152472B11219617121612123674
8187 737 1316 1976 778 1469 15497 2367 4
28655 961 1795 2429 9B3 1738 13935 2367 51
3611213 1218 1768 2882 1253 1961 12372 2367 21219
34B7f 1488 1741 2953 1524 21B5 112181121 2367 366
33631 1759 1714 3024 17~5 241219 9571 2367 524
3241217 21213121 16B7 3161 212166 2633 BB17 2367 682
312112182 212147 1387 3366 19~5 2694 8064 2367 839
27288 1955 112158 3571 1885 2737 731121 2978 1073
24495 1863 .756 3776 1781 2780 6557 3588 1315
22599 1897 71218 3981 1724 2823 5803 4199 1557
2161212 2058 659 4186 16'67 2866 4567 5466 1749I.,. .
212161215 2218 61121 439121 16'10 2909 3277 6493 1485
1961218 2379 562 4595 1552 2952 1987 710B 1221
18610 2539 513 48121121 1495 2995 697 7508 957I.
17613 2700 464 5005 1444 312138 0 8014 693
1661b 2861 416 521121 1393 312181 121 8219 429
15618 312121 367 5414 1341 3124 121 8954 165
14621 3182 318 5619 129121 3167 0 912105 121
13624 3342 27121 5824 1239 j21121 0 8559 121
1262'1 .3,503 221 6029 11 88 3253 0 7436 121
11629 3663 173 6234 1136 3296 121 5852 121
1121632 3824 124 6439 112185 3339 121 4541 121
9635 3984 75 6643 1034 3382 121 3229 0
8638 4145 27 6848 983 3425 121 1918 0
7640 431215 121 7053 931 3468 0 61216 121
6643 4466 0 7258 880 3511 0 121 0
! '-------------------.._-----j------------------------------------------------------------_._-------';""'"---
Source.ADFl!d3 1984b J EWntl~11985c
TABLE E.3.2.43 (CONTI NUED)
----------------------------------------------------------------------------------------------------
Mainstem SC 10 LSC 11 USC 11 SC 21 Slough 21
Discharge 133.7R 133.8L 133.8R 134.9R 136.3R 137.5R 138.7L 139.0L 141.4R 141.6R
---------------------------------------------------------------------------------------------------
Gp 3 Gp 6 Gp 10 Gp 4 Gp 6 Gp 2 Gp 10 Gp 1 Gp 3 Gp 5
---------------------------------------------------------------------------------------------------
(cfs)(sq.ft.(sq.ft.(sq.ft.(sq.ft.(sq.{t.(sq.ft.(sq.ft.(sq.ft.(sq.ft.(sq.ft.
WUA)WUA)WUA>WUA)WUA)WUA)WUA)WUA>WUA>toIUA)
401210 96 0 168 6248 1644 121 21212 25lZl 1260 5231
5000 96 121 183 7811 2055 0 407 250 1575 5231
6000 106 0 197 8934 2465 1 611 25lZl 1890·5231
7000 117 0 211 9640 2876 3 816 2512)221215 5231
B01Zl0 126 0 221 9921 3284 4 1021 250 2520 5231
912100 134 0 231 10137 4028 5 1226 250 2835 5231
112100121 litl 0 26121 112114121 4769 7 1431 250 3159 52~H
1101210 133 0 29121 9816 5334 8 1758 266 3465 5231
12000 116 0 291 9462 5899 9 2167 293 385121 5231
1312100 98 0 272 9087 6434 11 2576 320 3708 5231
1401210 81 0 253 8569 6968 12 2985 347 3665 5231
15000 63 0 234 8300 7567 14 2965 366 3464 5231
16000 46 0 216 7929 8165 15 2516 378 3252 52.3 I
17000 41 0 197 7588 9876 20 2068 389 2845 5231
1801210 37 0 167 7248 11323 25 1630 ,400 2482 5231
19000 33 162 137 6907 12470 3121 1290 4f2l121 2132 5231
20000 30 722 11216 6566 1328121 45 1196 372 1828 5231
21000 26 958 77 6226 13671 60 1103 344 1632 5231
2212100 23 2056 69 5885 14127 75 1009 316 1480 6261
230121f2l 19 3408 61 5545 14311 90 915 289 1337 7292
240121f2l 15 496121 53 5204 13516 105 822 261 1203 8207
25000 12 6228 44 4863 12437 120 728 233 1186 10134
2612100 8 7310 36 4523 11242 135 634 205 1253 11205
270f2l0 5 9392 28 4182 10048 150 541 177 1366 13902
28000 1 9474 20 3842 8853 165 447 149 1650 16083
29000 0 10556 11 3501 7659 18Ql 353 121 2366 161~4
312112100 0 11638 3 3160 6464 195 260 93 3118 14572
31000 0 12720 0 2820 5269 210 166 66 3884 12444
32000 0 13472 III 2479 4075 225 72 38 4653 If2lf2l97
3312112112l 0 14884 0 2139 2880 24121 121 10 5421 7666
::'~400f2l 0 15966 121 1798 1686 255 0 0 6190 5237
3500f2l f2l 17048 0 1457 491 270 f2l III 6958 28f2l8
-------------------------------------------------------------------------------_._----.._-------------
Source:ADFll,13 1984b;EWn,A 1985c
r
I
TAF.ll.E 'E.3.2.44s R~S~'C1NSE OF CHUM SF'AW~ING HABITAT (WUA PER 10121111 sa.FT.)
Air IFG AND DIHAB NODE~ED SITES INCLUIlED IN
REP~ESENTATIVE GROUPS I (RG)2,3,AND 4.I ,
------o----------·----;;;~;~--r;;;~;~---;;;~;~---;;~~;~---;;;~;~---;;;~;~---;;;~;~---;;;~;~---;;;~;~-
Mainstem I Whisker's Ms II Slough Slough Lower SC
Discharge I West SC 'sc BA 9 SC 11 21
(cfs)I (RG 3)(RG 3)(RG 4)(RG 2)(RG 3)(RG 3)(RG 4)(RG 2)(RG 3),
----_._------:------------------'j""--:"'-----------------~--------------------------------------------------
401ll11l
512100
611100
71210121
B01210
9121flJlll
100111111
11121f21121
121llf21111
13f210f21
141210121
150f21121
161llf210
17f21111f21
IBI1I1210
1911lf21121
2017.11ll121
21f21f21121
22f211l1f21
231l1f211i'l
24f211l11i'l
25f2101ll
261l1f211l1
27f21f211ll
2BIlIlZIf2I
291Z11ll1ll
31Z11i!l11l1Zl
3112l1ll121
321l1f21121
331Zl1ll1ll
340121111
351ll1Zli21
36flllZllll
371l1f210
3BIlIf2If2I
390111f21
401l11l11i!l
411Z1i211i!l
421l1ft11l1
431lJf2IIi!l
44121f211i!l
451i!l12lf21
f21.f21
0.III
f21.1i!l
Ill.III
0.III
0.III
50.8
125.2
136.4
124.B
114.3
11114.9
92.2
79.1
67.4
59.2
53.9
49.2
44.B
41l1.B
}37.1
33.7
30.5
27.6
24.B
22.3
19.9
17.6
15.5
13.5
11.6
9.B
8.0
6.2
4.4
2.6
f21.9
121.0
121.121
0.0
0.121
121.121
11.2
11.2
11.2
11.2
12.9
IB.l
23.3
4
33.3
2
21.B
19.2
17.6
16.5
15.5
14.B
14.2
13.7
13.2
12.9
12.5
12.2
12.121
11.B
\11.6
:11.4
'11.2
11.1
110 •9
;1121.B
,lfll.7
i10.6
'lfll.5
:10.4
11111.3
:10.2
11f21.1I.;10.0
9.9
9.B
9.7
9.6
0.111
0.0
33.2
46.4
49.6
44.5
39.6
34.9
30.4
26.1
22.6
20.3
18.1
16.(1)
14.!2I
12.1
9.3
6.5
3.9
1.3
111.0
0.0
0.!2I
0.0
1ZI.121
fll.0
0.III
fll.12I
0.111
121.0
l2I.fll
0.III
111.111
121.0
fll.fll
0.0
fll.1lI
0.0
fll.12I
0.0
0.III
0.0
35.7
35.7
35.7
35.7
35.7
35.7
35.7
35.7
35.7
35.7
35.7
35,.7
35.7
35.7
35.7
35.7
35.7
38.7
41.B
44.8
47.8
62.9
6fll.fll
65.2
4
75.4
81?J.3
184.9
'89.4
,94.0
9B.6
.1lI2.8
11216.III
~09.0
11219.4
~09.2
1III 8.8
1III 6.121
100.4
91.121
82.121
7121.121
36.7
36.7
36.7
36.7
36.7
38.'4
4121.1
42.6
45.fll
47.3
49.6
51.B
54.1
56.3
58.4
66.121
73.5
7B.4
B3.3
82.B
B2.2
82.3
B2.4
77.3
72.2
58.5
44.9
34.fll
23.1
2fll.11I
18.III
17.5
17.III
16.5
16.III
15.5
15.III
14.5
14.III
13.5
13.121
12.5
8.8
9.5
10.2
1121.B
11.3
11.2
11.1
10.9
1111.5
9.B
9.1
B.4
7.B
7.1
6.III
4.9
3.8
2.7
2.5
2.2
1.9
1.6
1.3
1.III
0.7
fll.4
0.1
Ill.III
111.111
0.111
fll.1lI
0.111
13.!2I
0.0
121.111
0.111
0.0
0.0
121.III
fll.0
fll.1ll
0.0
45.0
44.8
44.7
42.2
39.7
38.5
037.4
34.9
32.3
30.8
29.2
27.7
26.2
24.9
23.6
22.3
21.1
19.9
IB.6
17.5
16.3
15.1
13.9
12.7
11.6
10.6
9.5
8.4
7.3
6.2
5.1
4.fll
2.9
1.8
Ill.7
0.fll
121.0
111.0
Ill.0
12I.1i'J
Ill.III
0.121
3121.B
31l1.B
30.B
31l1.B
33.4
36.1
3B.7
41.2
54.3
51.8
56.3
6111.7
65.1
69.3
73.2
77.1
B1.1
B5.1
BB.7
91.5
94.0
94.4
94.2
93.9
91.5
B6.6
7B.5
7111.7
61l1.4
51l1.1
39.B
29.5
19.2
B.~
Ill.III
0.III
0.III
Ill.III
0.III
0.0
Ill.III
121.III
19.3
19.3
19.3
19.3
19.3
19.3
19.3
24.1
2B.B
27.0
25.1
23.0
21l1.9
17.6
14.4
12.0
9.5
8.3
7.2
6.4
5.7
5.7
5.7
6.4
7.1
9.9
12.B
15.6
IB.4
15.7
14.5
13.3
12.1
9.9
B.7
7.5
6.3
5.1
3.9
2.7
1.6
1.1-------------..:.-------o-------t---------------------·--------------------------------------------------
Source:ADF&G 1984b;EWH,A 1985c
~
l--
TABLE E.3.2.45:RESPONSE OF CHINOOK REARING HABITAT AREA
TO DISCHARGE IN EACH OF THE REPRESENTATIVE GROUPS
Weighted Usable Area
Mclinstem
Dilscharge
(cfs)
5Q1 l21 !il
6l21l210
7l21l21l21
8l21l21l21
9l21l210
1012100
11l210l21
1212100
1312100
1401210
15l21l21121
161211210
1701210
18Q10l21
191210121
21Zl01210
2100121
22000
23000
2401Zlfll
2501210
2600121
27000
28000
29000
312101210
31000
32000
33000
3412100
35000
RGI
(sq ft)
58382
61249
63491
65213
66487
67361
69512
69891
71233
72256
72907
73164
73486.
73193
72625
71702
7121338
68667
67931
67708
·64491
62257
64045
66273
67891
68818
69848
70504
71144
71836
7211134
RG2
(sq ft)
211176
218344
225752
238554
257475
270380
287565
31111749
339377
373909
395242
417797
444568
473671
513739
554029
6l211.492
662735
754585
866243
1008703
1169711
1314448
1406222
1444974
1462318
1458037
1438566
1451848
1397423
1313099
RG3
(sq ft)
153979
163299
188181
229113 .
294676
402029
658174
856488
1173219
1294098
1359539-
1353576
1329916
1295405
1296231
1268329
1237917
1179275
111118650
1062812
111119704
972946
925935
905280
901735
887624
889489
879814
867872
846441
85711161
RG4
(sq ft)
3677949
3863286
41211217191
4258077
4175694
3797023
336331217
3347555
3239630
301114490
2871869
2744514
2672308
252141216
241531112
2351648·
2316387
2245428
2177461
2111344
2047623
1977679
1917723
1861423
18121311163 •
1746746
1689974
1645426
1604911
1567743
153111289
RG5
(sq ft>
2112119
36522
52449
66314
76593
86794
120917
15111913
177206
177463
173343
1'65896
160448
168233
168962
164835
167174
192991
216495
262627
296116
319718
317828
299814
279143
242398
214603
191810
167887
151771
141533
RG6
(sqft)
95987
111160
142146
186170
217614
251758
292143
36111336
426912
486412
543176
564189
61211939
655729
67481114
687275
70319111
744392
755478
76151117
798554
864035
894882
949701
991364
1065805
1095351
1123087
1138026
1138884
1126165
RG7
(sq ft)
28111801
319996
319897
367372
377098
387789
381298
350522
333379
292832
249206
21911142
188665
163502
144490
127988
118041
10911188
103862
99894
96847
94536
92256
90014
87814
85655
83542
81475
79457
77481
75551
Rr:l8
(sq ft>
111
o
111
121
111
24873
37412
5188111
63942
69686
11511199
196152
21115595
212097
219207
238956
274356
347437
429862
517133
596966
648188
658:388
642629
61217215
539873
47111130
416385
369505
322716
282871
Rr:l9
(sq ft)
36121966
373281
378925
384095
463673
453914
447278
410868
436612
468255
436154
464664
422027
46530111
49581117
491800
525173
565358
591065
627531
640311
671899
681802
685405
659181
647658
67121398
661724
628836
60121512
575164
SIt!URCE:EWT8,A 1985a
TOTAL CHINOOK REARING HABITAT AREA
RESPONSE TO DISCHARGE IN
ALL REPRESENTATIVE GROUPS AND IN
REPRESENTATIVE GROUPS 2,3 AND 4
Total Weighted Usable Area
TABLE E.3.2.46:
Mainstem'
Discharge
(cfs)
All
Representative
Groups
(sq ft)
Representative
Groups
2,3,and 4
(sq ft)
5000 4860259
6000 5147138
7000 5378032
8000 5794908
9000 5929310
10~00 5741921
11000 5657606
12000 5909202
13(zlgll?l 6~615~0
14000 6239400
15000 6216535
16000 6198995
17000 6098952
18000 6028537
19000 6001167
_____._____~(2)00g>__~2~65~2_
21000 6014068
22000 6115371
23000 6205389
24000 6376799
25000 6569315
26000 6780969
27000 6867308
28000 6906761
.....---------.-.--.--...-..·-29000---·--·-·-,·-------6842379
--.------....-....-···--·--------·-·---50000-~------6_746895-
31000 6642272
32000 6508791
33000 6379487
34000 6174806
35000 5973767
36000 5770350
37000 5566933
38000 53635~6
39000 5160099
40000 4956682
41000 4753265
42000 4549848
43000 4346431
44000 4143014
45000 3939597
4043104
4244929
4421124
4725744
4727845
4469432
4309046
4514792
4752226
4672497
4626649
4515888
4446792
4290482
4225272
4174006
4155796
4087438
4040696
4040400
4076030
4120336
4158107
4172926
--4-149772 ...
.----4096688--
4037500
3963806
3924631
3811607
3700449
3588400
3476351
3364302
3252253
3140204
3028155
2916106
2804057
2692008
2579959
.1
~)
j
-1
:J
.1
'j
J
'I
TABLE E.3.2.47:RESPONSE OF MIDDLE RIVER
CHUM SPAWNING AREA REPRESENTED
IN IFG AND DIHAB MODELED SITES
Mainstem
Discharge
Total WUA
in Modelled
Sites
IJ
------------------------------------------------------
(cfs)(sq.ft)
4000 18965
5000 21554
6000 30653
7000 40102
8000 46690
9000 48205 •It.
10000 57720
11000 79214
12000 87451
13000 86041
14000 84911
15000 ""~f 84052
16000 80588
17000 78110
.18000 75454·
19000 74083
20000 74195
21000 72925
22000 73265
·23000 73381
24000 73316
25000 74209
26000 74557
27000 76993
28000 76752
29000 75168
30000 71487
31000 67562
32000 63094
33000 59223
34000 55137
35000 51791
TABLEE.3.2.48:RESRONSE OF CHUM SPAWNING HABITAT IN
R~PRESENTATIVE GROUpSi2,3,AND 4
~!.r
,I :'_-..:_~.:.-_-.:.·w .....:.~_
(cfs)
I WEIGHTED USEABLE AREAS IN REPRESENTATIVE GROUPS Total HabitatI.NAINSTEM I 'Area in
DISCHARGE I G~O~P 2 GROUP 3 GROUP 4 Groups
Ii'-------------------F;~-ft)-------·----"(;~--ft)-----------"(;q-ft)------------"(;q-ft)---------
,,
4000
5000
6000
7000
8000
9000
10011.10
11000
1212100
13000
14000
15000
16000
17000
18000
19011.10
201210121
211211210
22000
231210121
2400121
25000
2611.100
270121121
2811.100
2900121
3000121
31121121121
32000
3300121
3411.11210
35000
3611.10121
3700121
38000
39000
400121121
41011.10
42000
43000
44000
45000
5612135 :26538 398699 481271
57530 29778 434326 521634
59030 33402 596691 689123
60548 37889 658767 757205
64581
,
44927 675473 784981,
71346 55924 667328 794598,
77846 94752 655907 828505
85560 157839 622324 865723
1~0418 186273 583403 870095
112454 189401 556573 858428
i 13121125 193207 529487 85282121
145288 198148 50711121 850546
15860121 197312 483362 839275
1?5686 193239 461484 830409
200945 188456 438668 828068
220704 190576 415029 826309
24581212 I 387124196412 829338
I277165201763 358172 837100
I31262520978121 327165 849570
314436 21121301 299101 853837
37275121 Z1l019 275098 858866,
409889 215585 257668 883141
I ,
425942 220196 239687 885825
4~5208 218058 221189 884455
461654 215509 203963 881125
470803 199854 188083 858740
471975 182797 170040 824811
467095 196205 151612 784911
457526 149012 132819 739358
4~1734 139506 113679 694919
420823 13395121 94207 648981
393133 1*0802 74419 598353
3~8573 1:p937 54328 536838
3.21432 123226 33947 478605
279346 li8950 13287 411583
248864 114936 0 363799
220502 110381 0 330883
193579 I1f16762 (i]300341
i 167421 106045 0 273466
,138447 1~1538 0 239985
I110969 98809 0 209778
91822 97402 0 189223
-'--
~---
TABLE E.3.2.49:TOTAL CHINOOK REARING HABITAT
IN ALL REPRESENTATIVE GROUPS
DURING SUMMER WEEKS
UNDER NATURAL FLOW REGIME
-------------------------------------~--------------------------
Natural Flow Regime I
1-----------------------------------~---t
Total Habitat Area Exceeded
Calendar I 901.501.101.
Week I Percent of Time
------~--------------------------------------------------------
(sq ft)(sq ft)(sq ft)
22 5887756 6131097 6843402
23 5476820 6222510 6893240
24 3494928 6151734 6780969
25 5218277 6187294 6840933
26 5958463 6372627 6892074
27 5960915 6245443 6836489
28 5963999 6108808 6790478
29 5954151 6240076 6873055
30 5971538 6137691 6847559
31 5517503 6294162 6815705
32 5954772 6171091 6823350
33 4956682 606~~121 6376799
34 5561034 6096961 6376799
35 5517503 6138112 6292156
36 5685606 6000258 6316496
37 5690184 6008042 6228691
38 5292193 5960600 6259540
39 4987661 5809273 6216278
------_.._-
I
Calendar Week 22 =Week Beginning.May 27
.'
TABLE 1 E'.,..'?~nl.I i---'•..:...\:1"'.TOTf'\LCHINOOI<REARING HABITAT
IN REPRESENTATIVE GROUPS 2,3,AND 4
DU~ING SUMMER WEEKS
UND~R NATURALRLOW REGIME
I
~~-~-------~-~~-~------------~-~---------~---~---~--~----------1";,.!--.
,
Calenpar
WeeJ(,
I
I
1---
I
I
I
Natural Flow Regime I
--~-----------~---------------------I
Tot~l Habitat Area Exceeded I
:90%50%10%I
Percent of Time
i~~------------i~-------------~---------------------------------
I (s;q ft)(sq ft)(sq ft)
I
2:2 ""8~"':!'1""""4125226 4543200"_'i:J "_,"_,"_,
2:3 ""41'"'671""-4124438 4449608....'I"::'--'
2'4 '?~-~0'?0 4071885 4488465L.31"::'~..:..
2:5 32i84299 4076823 4581977
2'6 3~28240 4113942 4220266
217 40,25392 4119204 4230208
r 2:8 39t76770 4125798 4258885
2;9 "'=*"i~-;r '?'4091048 4245477".)~iJ...,1 ...,7
30 3~66421 4137456 424046::~
1 31 34149123 4101473 4181791
'13:2 412P9301 41::~8079 4230401
3;3 31140204 4171382 4496151
34 4040200 4176297 4629213
3:5 4O,37705 4332384 4712545
36 4121 96 153 4398222 4734924
3,7 41151235 4528447 4721533
38 41145776 4450270 4718252
39 41'16902 4504139 4720054
:;-----:-0004--
i I ICalen~ar Week 22 =Week Beginning May 27
TABLE SUMMARY OF LOCAL AND MAINSTEM DiSCHARGES AT SUCCESSFUL AND UNSUCCESSFUL
THRESHOLDS FOR CHUM SALMON ACCESS TO SPAWNING HABITATS
I I I Mai nstem Di !Icharge
I I I Local Discharge Thresholds (c)I Backwater Thresholds(d)
Bite Name I River Mile IRepresentativel Passage I ----------------------------------------------------------
Designations (a)I Group I Reach (b)I Successful I Unsuccessful I Successful I Unsuccessful
--------------------------------------------------------~-----------------------------------------------------------
Whi!lkerl's Creek
sloubh
101.4L 2 I
II
(cfs)
14
5
(cfs)
6
1
(cfs)
e
e
(cf!l)
e
e
Mainste/n II 115.0R 3 I 1 0.5 9200 S600
II :5 1 12500 I1SI1I0
III 13 4 e e
IVL 4 1 e e
2 IVR 11 3 1970111 18800
VR 4 2 e e
VIR 2 I1I.S e e
VIIR 7 3 e e
VIIIR 2 0.7 e e
Slough A 126.IllR 2 I 2 Ill.8 771110 721110
II 5 2 1601110 14600
III 4 1 19001ll 17600
IVL f 2500111 2360111
IVR 6 2 e e
VR 6 2 e e
VIR 3 0.6 e e
VIIR 7 3 e °e
VIIIR 11 3 e e
IXR 4 0.8 e e
XR 2 0.8 e e
Blough 128.8R ::5 I
II
III
IV
V
5
6
5
3
0.9
4
3
2
1
111.9
e
e
e
e
11600
e
e
e
e
11119111111
Slough ~A 133.9R 1 I 9 4 11500 11118QlIII
II 3 2 e e
III 4 2 e e
IV 4 2 e e
V 4 3 e e
VI 6 3 e e
VII 4 1 e e
VIII 9 3 e e
IX 3 0.8 e e
X 2 111.6 e e
XI 9 3 e e
TABLE E.3.2.518 (CONTINUED)
___________________~-------------~---~--~-------------J _
Site Name
Ii I
I i I
River Mile l~eprmBentl
Designati ons (a)I!Group I
I Mainstem Discharge
Local Discharge Thresholds(c)I Backwater Thresholds(d)
Passage ----------------------------------------------------------Reach (b)Successful I Unsuccessful I Successful I Unsuccessful
-------------------~-----------------t--------------------~-----------------------------------------------------------i i (cfs)(cflll)(cfs)(cft!l)
Side Channel 1111 133.8L 6 I f f 183111111 177111111
II f f e e
III f f e e
IV f f e e
V f f e e
VI f f e e
--~-----------------~----------------+--------------------~-----------------------------------------------------------Slough 11 1:53.6R i 1 I 4 1 163111111 134111111
II 1.4 9 194111111 183111111
1.11 9 3 334111111 32111121121
IV :5 1 41113121111 388111111
V 3 1 e e
VI 2 111.6 e e
VII 111.3 111.4 tit e
-------------------------------------+--'------------------~-----------------------------------------------------------Upper Side Channel 11 136.3R 6 I
II
8
9
2
9
e
e
tit
e
I 9 9 e e
II 9 9 e e
III g g e e
IV 9 9 e e
V g 9 e e
VI 2 111.6 13121111111 13111111111
VII 2 111.7 153111111 1450121
VIII 2 111.9 191211210 181111111
IX 4 1 256111111 2480111
1139.9R
-------------------~-----------------+--------------------~~------------------------~---------------------------------Slough 19 139.7R·3
-------------------~~----------------+--~-----------------~~~---------~-----------------------------------------------
710121
97121121
123111111
211100111
e
e
e
e
e
e
e
78121111
1031110
e
e
e
e
e
e
e
2
3
3
1
1
4
5
2
2
5
7
7
4
4
17
2111
7
5
I
II
III
IV
V
VI
VII
VIII
IX
5
2
3
141.6R
14111.2R
141.4RSideChannel21
Slough 2111 I 2 111.6 130121111
II 2 111.5 2111110
III 3 1 e e
IV 9 gee
V 9 gee
VI 1111 4 e e
-------------------------------------~--------------------~-----------------------------------------------------------I·•
I
'-----
TABLE E.3.2.511 (CONTINUED)
----------------------~-----------------------------------------------------------------------------------------------
Site Name
I
I I
River Mile I Represent I Passage
DesignationB(a)I Broup I Reach (b)
I
Local Discharge Threshold.(c)I
Successful I Unsuccessful
Mainstem Discharge
Backw.ter Thresholda(d)
Succes.ful I Unaucce.aful
(cfs)(cf.)(cfs)(efa)
Sloughl21 142.1R 2 I 4 1 at e
II 2 121.4 e e
IIIL 3 121.8 e e
IIIR g g e e
Slollghl22 144.4L 2 I
II
III
3
2
4
1
121.7
2-e
178121121
227121121
e
16121121121
219121121
a/SoU'
b/SOli
rea
c/SOli
d/Sou
e/Inf
at
f/Val
g/No
EWT~A and AEIDC 1985
ADF~B 19851 Design.tions of "L"and "R"refer to p ••••ge
in left .nd right ch.nnels,looking upstream.
ADF~B 19851
eel ADF~B 19851
uenee of backwater w.s not evalu.ted .ince bre.ching flow occurs
ischarges lower than those required for providing b.ckwater influence.
ee not available
ross section data available.
1
1
)
.l
\
I
I.
I
j
)
1
1
1
.j
I
(sq ft)(sq ft)(sq ft)
32 72935 74117 76821
33 35061 73755 78712
34 45002 74129 84101
35 44286 76030 85363
36 47448 75257 86202
37 47448 76554 85219
38 36322 74376 86928
39'·26285··'62440·86438···
TABLE E.3.2.52:
Calendar Week 32 =Week Beginning August 5
Calendar
Week
TOTAL CHUM SPAWNING HABITAT .j
IN IFG AND DIHAB MODELED SITES
DURING SUMMER MONTHS
UNDER NATURAL FLOW REGIME
------------------------------------------------------------------------1
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10%:•.{1
Percent of Time I
I
I 1
!I TABLE E.3.2.53:TOTAL CHUM SPAWNING HABITAT
IN REPRESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS
UNDER NATURAL FLOW REGIME
Calendar-
Week
Natur-al Ffow
Modelled Habitat
90%50%
Per-cent of
Regime
Ar-ea E>:ceeded
10%
Time
(sq ft)(sq ft)(sq ft)
32 826654 849978 883525
33 330883 832670 858434
34 689191 836728·862500
35 620955 852626 868158
~6 789790 840645 866908
37 789790 840943 864098
38 729972 844361 867598
39 608728 825264 865603
Calendar-Week 32 =Week Beginning August 5
TABLE E.3.2.54:TOTAL CHUM SPAWNING HABITAT
AVAILABLE FOR INCUBATION OF EMBRYOS
IN IFG AND DIHAB MODEL SITES
UNDER NATURAL FLOW REGIME
Natural Flow Regime
Modelled Habitat Area Exceeded
Calendar 90%50%10%___________~==~~=~==~~_~~_~~~:~~_~~ll
(sq ft)(sq ft)(sq ft).
42731
80392
4915738552
21348
20021 29479
16393 21148
13242 19511
12294 16391
11547 15172
108:Z2~.~14053 .
44783
5552
21116
19923
15404
11066
8127
7586
7112
6230
40
41
42
43
44
45
46
47
·48
TABLE E.3.2.55:TOTAL CHUM SPAWNING HABITAT
IN REPRESENTATIVE GROUPS 2,3,AND 4
AVAILABLE FOR INCUBATION OF EMBRYOS
DURING EARLY WINTER WEEKS
UNDER NATURAL FLOW REGIME
<sq ft)(sq ft)(sq ft)
40 514813 776940 855079
41 496205 746040 797989
42 390912 518425 768288
.43 280822 497739 667517
44 206225 415999 515297
45 192508 336047 489788
46 180477 311984 415938
47 158098 293034 385017
48 140892 275889 356622
il
I]
I IlJ
Calendar
Week
Natural Flow
Modelled Habitat
90%50%·
Percent of
Regime
Area E)·(ceeded
10%
Time
lJ
11
Calendar Week 40 =Week Beginning October 1
TABLE E.3.2.56:STREAMS CROSSED BY DENALI HIGHWAY
(CANTWELL TO WATANA ACCESS JUNCTION)
Miles from
Stream Richardson Highway
Trib.to Jack R.132.5
Trib.to Jack R.132
Unnamed Creek (Jack R.System)128
Edmonds Creek 121
Nenana R.Oxbow 119.75
Nenana R.Oxbow 119.5
Trib.to Nenana R.118
Trib.to Nenana R.117.8
Trib.to Nenana R.116.8
Unnamed Creek (Nenana System)114.5
Species Present
grayling
grayling
not sampled
Various species from thE
Nenana River,including
grayling,northern pike,
burbot,whitefish,and !
sculpin.r
"
j
1
I
TABLE E.3.2.57:WATER BODIES TO BE CROSSED BY THE SUSITNA
TRANSMISSION LINE (ANCHORAGE TO WILLOW)
Stream Fish Species Present
Ship Creek pink,chinook,coho,chum,and sockeye
salmon;Dolly Varden;rainbow trout.
Fossil Creek none
Otter Creek rainbow trout
Knik Arm pink,chinook,coho,chum,and sockeye
salmon;Dolly Varden;Bering cisco;
enlachon;lamprey
Unnamed Creek
(T,R4W,Sec.18)unknown
Little Susitna River coho,pink,chinook,chum,and sockeye
salmon;rainbow trout;Dolly Varden;
grayling
lJ
Tributary to Fish Creek
(Tl7N,R5W,Sec.18,19)
Fish Creek
Unnamed Creek
(T18N,R5W,Sec.8)
Unnamed Creek
(T18N R5W,Sec.5)
Unnamed Creek
(T19N,R5W,Sec.)
Willow Creek
unknown
chinook,sockeye,pink,and coho salmon;
rainbow trout
unknown
unknown
unknown
coho,chum,pink,and chinook salmon;
grayling;rainbow trout;Dolly Varden;
whitefish
TABLE E.3.2.58:WATER BODIES TO BE CROSSED BY THE
SUSITNA TRANSMISSION LINE (HEALY TO FAIRBANKS)
Page 1 of 3 .]
Stream
Nenana Rive r 1F!
Dry Creek
Panguinge Creek
Little Panguinge Creek
Slate Creek
Tributary to Slate Creek
Rock Creek
Unnamed Creek
T98,R9W,836,FM
June Creek
Bear Creek
Nenana River 112
-Unnamed creek·'"
T88;R8W.,.811,FM----
Windy Creek
Tributary to Windy Creek
Unnamed Creek
T82,R9W,81,FM
Unnamed Creek
T78,R8W,818,FM
Unnamed Creek
T72,R7W,88,FM
Unnamed Creek
T78,R7W,85,FM
Fish Species Present
coho salmon,grayling,round whitefish,
longnose sucker,slimy sculpin,burbot,
Dolly Varden
unknown
coho salmon,longnose sucker,round
whitefish,Dolly Varden,grayling,
slimy sculpin
coho salmon,grayling,round whitefish,
slimy sculpin,Dolly Varden,longnose
sucker
unknown
unknown
unknown
unknown
unknown
unknown
grayling;northern pike;slimy sculpin;
chum,chinook and coho salmon;inconnu;
whitefish;burbot
-·unknown-
unknown
unknown
unknown
unknown
unknown
unknown
-,
-(
r
TABLE E.3.2.58 (Page 2 of 3)
8tream Fish 8pecies Present
lJ
Unnamed Creek
T68,R7W,832,FM
Tributary to Fish Creek
T68,R7W,821,FM
Tributary to Fish Creek
T68,R7W,822,FM
Fish Creek
Unnamed Creek (2 crossings)
T68,R7W,810,FM
Unnamed Creek (2 crossings)
T68,R7W,83,FM
Unnamed Creek
T48,R7W,834,FM
Unnamed Creek
T48,R7W,828,FM
Tanana River complex
Tanana Tributary complex
Little Goldstream Creek
Little Goldstream Tributary
T38,R6W,84,FM
Little Goldstream Tributary
R38,R6W,83 FM
Little Goldstream Tributary
T38,R6W,82,FM
Little Goldstream Tributary
T38,R6W,81,FM
unknown
unknown
unknown
grayling,round whitefish,slimy
sculpin,Dolly Varden,longnose sucker
unknown
unknown
unknown
unknown
chum,coho and chinook salmon;
inconnu;northern pike;grayling;
whitefish;burbot
unknown
grayling,round whitefish,blackfish,
longnose sucker,slimy sculpin
unknown
unknown
unknown
unknown
Little Goldstream Tributary
T28,R5W,832,FM (2 crossings)unknown
Bonanza Creek Tributary
T28,R5W,833,34,36,FM
(3 crossings)unknown
TABLE E.3.2.58 (Page 3 of 3)
Stream Fish Species Present
Ohio Creek Tributary
T2S,R5W,S7,FM
Ohio Creek Tributary
T2S,R4W,S5,FM (2 crossings)
Ohio Creek Tributary
TIS,R4W,S33,FM
Ohio Creek Tributary
TIS,R4W,S27,FM
Ohio Creek Complex
Ohio Creek Complex
Alder Creek Complex
Emma Creek
Alder Creek Tributary
.__rl~LR3W,813,FM
Sources:ADF&G 1982g
Tarbox et ale 1978
unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
!
j
j
-I
J
j
1
I IIJ
TABLE E.3.2.59:SUSITNA HYDROELECTRIC PROJECT
FLOW CONSTRAINTS FOR ENVIRONMENTAL
FLOW REQUIREMENT CASE E-VI
Gold Creek Flow
(cfs)
Calendar Water
Week Week Period Minimum Maximum
1 14 31 Dec -06 Jan 2,000 16,000
2 15 07 Jan -13 Jan 2,000 16,000
3 16 14 Jan -20 Jan 2,000 16,000
4 17 21 Jan -27 Jan 2,000 16,000
5 18 28 Jan -03 Feb 2,000 16,000
6 19 04 Feb -10 Feb 2,000 16,000
7 20 11 Feb -17 Feb 2,000 16,000
8 21 18 Feb -24 Feb 2,000 16,000
9 22 25 Feb -03 Mar 2,000 16,000
10 23 04 Mar -10 Mar 2,000 16,000
11 24 11 Mar -17 Mar 2,000 16,000
12 25 18 Mar -24 Mar 2,000 16,000
13 26 25 Mar -31 Mar 2,000 16,000
14 27 01 Apr -07 Apr 2,000 16,000
15 28 08 Apr -14 Apr 2,000 16,000
16 29 15 Apr -21 Apr 2,000 16,000
17 30 22 Apr -28 Apr 2,000 16,000
18 31 29 Apr -05 May 2,000 16,000
19 32 06 May -12 May 4,000 16,000
20 33 13 May -19 May 6,000 16,000
21 34 20 May -26 May 6,000 16,000
22 35 27 May -02 Jun 6,000 16,000
23 36 03 Jun -09 Jun 9,000*35,000
24 37 10 Jun -16 Jun 9,000*35,000
25 38 17 Jun -23 Jun 9,000*35,000
26 39 24 Jun -30 Jun 9,000*35,000
27 40 01 Jul -07 Jul 9,000*35,000
28 41 08 Ju1 -14 Ju1 9,000*35,000
29 42 15 Ju1 -21 Ju1 9,000*35,000
30 43 22 Ju1 -28 Ju1 9,000*35,000
31 44 29 Ju1 -04 Aug 9,000*35,000
32 45 05 Aug -11 Aug 9,000*35,000
33 46 12 Aug -18 Aug 9,000*35,000
34 47 19 Aug -25 Aug 9,000*35,000
35 48 26 Aug -01 Sep 9,000*35,000
36 49 02 Sep -08 Sep 8,000 35,000
37 50 09 Sep -15 Sep 7,000 35,000
38 51 16 Sep -22 Sep 6,000 35,000
39 52 23 Sep -30 Sep 6,000 35,000
40 1 01 Oct -07 Oct 6,000 18,000
41 2 08 Oct -14 Oct 6,000 17,000
42 3 15 Oct -21 Oct .5,000 16,000
43 4 22 Oct -28 Oct 4,000 16,000
44 5 29 Oct -04 Nov 3,000 16,000
45 6 05 Nov -11 Nov 3,000 16,000
46 7 12 Nov -18 Nov 3,000 16,000
47 8 19 Nov -25 Nov 3,000 16,000
48 9 26 Nov -02 Dec 3,000 16,000
49 10 03 Dec -09 Dec 2,000 16,000
50 11 10 Dec -16 Dec 2,000 16,000
51 12 17 Dec -23 Dec 2,000 16,000
52 13 24 Dec -30 Dec 2,000 16,000
Note:Minimum summer flows are 9,000 cfs except in dry years when the
minimum will be 8,000 cfs.A dry year is defined by the one in ten
year low flow.
Source:HE 1985a
Low Discharge Year (Dry)
May 13 ,051 4,903 3,90311
June 21,763 8,800 7,800
July 19,126 9,000 8,000
August 17,392 9,000 8,000
September 10,422 6,800 5,800
October 4,515 5,032 4,032
Average Discharge Year
May 13,240 4,903 4,903
June 27,815 8,800 8,800
July 24,445 9,000 12,740
August 22,228 9,000 12,415
September 13,221 6,800 6,800
October 5 771 5,032 5,032--_..•.__...~._.._..-..,-_.._---_._-
High Discharge Year (Wet)
May 15-,032 4,903 4,900
June 31,580 8,800 10,752
July 27,753 9,000 20,547
August 25,236 9,000 15,505
','--,--_..._-,--.-.,-,--.._--,--,----,.September -15,124 -6,800-----_.-----6,800
----_._.__._~_..__..-0ct-obe-l"~----6-,-5-52-----5-,032---~-5-,-O32-
Corresponds to E-VI constraints in dry years presented in
Table E.3.2.59.
TABLE E.3.2.60:ESTIMATED MONTHLY MEAN DISCHARGE
AT GOLD CREEK DURING FILLING
OF STAGE I -WATANA RESERVOIR
II
Month
Gold Creek
Natural Flow
(cfs)
Gold Creek
Constraint
(cfs)
Gold Creek
Filling Flow
(cfs)
.l
1
l
)
j
I
·1
j
1
!
I
1
I
I
t
1
1
r
IJ
IJ
1/Percent change calculated as (HA filling -1)x 100,where HA is
the spawning habitat area.HA natural
TABLE E.3.2.62:·ESTIMATED CHANGES IN CHINOOK REARING HABITAT AREA
IN REPRESENTATIVE GROUP 2,3,AND 4 DUE TO FILLING
UNDER DRY,AVERAGE AND WET CONDITIONS
+12.4
+12.1
+8.0
-4.6
-10.7
+13.4
+16.8
+14.9
-7.4
-3.5
+9.0
0.0
+12.6
-5.0
-6.8
4,641,503
4,725,744
4,725,744
4,203,558
3,260,358
4,730,676
4,735,806
4,685,654
4,387,290
4,049,400
4,351,079
4,170,911
4,600,640
4,387,290
4,049,400
Rearing Habitat Area
4,130,942
4,216,389
4,376,438
4,405,591
3,650,922
4,170,847
4,055,560
4,077,757
4,739,112
4,197,559
3,991,031
4,170,150
4,084.,473
4,620,411
4,345,335
Natural Filling Changell
(sq.ft.)(sq.ft.)(%)
ling -1)x 100,where HA is the'-';;;'';''';;;';;~..l::.
HA natural
7,800
8,000
8,000
5,800
4,032
8,800
12,740
12,415
6,800
5,032
10,752
20,547
15,505
6,800
5,032
Discharge
Natural Filling
(cfs)(cfs)
21,763
19,126
17,392
10,422
4,515
27,815
24,445
22,228
13,221
5,771
31,580
27,753
25,236
15,124
6,552
Percent change calculated as
spawning habitat area.
Month
Average Year
Wet Year
Dry Year
June
July
August
September
October
June
July
August
September
October
June
July
August
September
October
.11
~----.._--~-----------~--_.,----~-~---
---.~---------_.".~-
TABLE E.3.2.63:COMPARISON OF PASSAGE CONDITIONS OF PASSAGE REACHES AFFECTED BY MAINSTREAM (Page 1 of 4)
MAINSTEM DISCHARGE UNDER NATURAL AND FILLING WET CONDITIONS FOR DRY,AVERAGE,
AND wET YEARS
.
Dry Year Average Year We Year
River Mile Passa§e Na ura 1 Fill'ng Na ural FiU'ng Na ural FiU'ng
Site Name Des igna t io n~1 Reach-I Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.
Whis~er's Creek lO1.4L I ---------------- --------
SIc ugh II --------------------- ----
cl
Maine tem II l1S.0R I S S SiD U S S S U S S S U
II S S U U S S SiD U S S S U
III ---- ---------------- -- --
IVL ------ ------------------
IVR U U U U U U U U S U U
U
VR ------------ ------------
VIR -- --------------- --
----
VIlR ------ -------------- ----
VIIIR ---- -- ------------------
Slou~h BA l26.0R I S S S U S S S U S S S U
II S U U U S U U U S SiD SiD U
III U U U U S U U U S U U U
IVL U U U U U U U U S U U U
IVR ------.------------------
VR ---- ---- ------ ----------
VIR -----------_.------------
VIlR ------------------------
VIIIR ------------ ------------
IXR ---------------------- --
XR ---------------- --------
TABLE E.3.2.63 (Page 2 of 4)
,
;,Dry Year Average Year Wet Year
River Mile ~a~saBe Natural Filling Natural Filling Natural Filling
8ite Name Designations.!/Re~ch-/Aug.8ep.Aug.8ep.Aug.8ep.Aug.8ep.Aug.8ep.Aug.8ep.
i
I '
!,
1'8lou gh 9
128.8R I 8 U U U .8 8 8 U 8 8 8 U
I II --------i -------- -- ------
II III --i-------------------- --
I IV --1----------------------II ,V --1·---------------------
I'iI
,18lough 9A 133.9R I 8 IU U U ,8 8 8 U 8 8 8 U
'II --1--------------------
ii iIll --1----------------------
,IV --1_---------------------II V --j,----------------------
I VI i--1----------------------
'VII --i·------:----------------
\!'III i·------.'--------.--------Ii :IXIi --1"';'-------------;--------
I X --1------ --
--------------I
i Xl ------------------------.
Ii I
118ide Channel 10 133.8L I U IU U U 8 U U U 8 U U U
II -------- ----------------
III -- -- ------------ --
------
IV ---- ---- ---------- ------
V --i------------------ ----
VI ------------------------
I
"
i--"---'
-~._..-
----
TABLE E.3 2.63 (Page 3 of 4)
Dry Year Average Year We Year
River Mile Passage Natural Fill'ng Na ural Fill'ng Na ural Fill'ng
Site Nam Designation~/Reach-/Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.
Slough 1 135.6R I S U U U S U U U S U SiD U
II U U U U S U U U S U U U
III U U U U U U U U U U U U
IV U U U U U U U U U U U U
V -------------- -- --------
VI -------- ---------- ------
VII -------------- -------- --
Upper Si e Channel 11 l36.3R I ------ ---------- -- -- ----
II ----....-------------------,
Slough 1 139.7R I -------------- -------- --
II -- ------------ ----------
III ---- --------------------
IV ---------------- --------
V ------------------------
139.9R VI S U U U S S U U S S S U
VII S U U U S U U U S SiD S U
VIII U U U U S U U U S U U U
IX U U U U U U U U SiD U U U
Slough 211 140.2R I S U U U S S SID U S S S U
II U U U U S U U U S U U U
III -------------------- ----
IV ---------- --------------
V ----------.--------------
I VI ------------------------
TABLE E.3.2.63 (Page 4 of 4)
[Dry Year Aver ge Year We Year
River Mile p;as~age Natulra 1 Filling Na ural Filling Na ural Filling
Site Name Designations!!1 R!each-I Aug.S!ep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.
!,
I
I •141.4R I S is S U S
S S U S S S US1deChannel21
i ,II S IS U U
S S S U S S S UII
I
III --;----------------------
,IV --f----------------------
I V --i------------- --------,
I VI ----------------------I VII ----I -------- ------------
i 141.6R VIII ----------------------
I IX ------------------------i
i
Slough 21 142.1R I --i--------------------I
I II ------------------------
I nIL ------------------------
I IIIR ------------------------
I SiD~lough 22 144.4L I IU U U S ·U U U S U
U u
I II U IU U U SiD U U U S U U
U
I !III --'-------------- --------I
!al
bl
~I
---I
Source:EWT&A and AEIDC 1985
Source:ADF&G 19851
S =Successful Conditions
SiD =Successful with Difficulty
U =Unsuccessful Conditions
._--'
TABLE E.3.2.64:ESTIMATED CHANGES IN CHUM SPAWNING HABITAT
AREA IN MODELLED SITES DUE TO FILLING
OF THE WATANA -STAGE I RESERVOIR
Chum Spawning Area
Natural Filling Changes~/
(sq.ft.)(sq.ft.)(%)
Discharge
Natural Filling
(cfs)(cfs)Month
Dry Year
August
September
17,392
10,422
8,000
5,800
77,069
66,790
46,690
28,833
-39.4
-56.8
Average Year
August
September
22,228
13,221
12,415
6,800
73,291
85,791
86,866
38,212
+18.5
-55.4
Wet Year
August
September
25,236
15,124
15,505
6,800
74,209
83,622
82,220
38,212
+10.8
-54.3
~/Percent change calculated as (HA filling -1)x 100,where HA ~s the
spawning habitat area.HA natural
TABLE E.3.2.65:ESTIMATED CHANGES IN CHUM SPAWNING HABITAT
AREA IN REPRESENTATIVE GROUP 2 DUE TO FILLING
UNDER DRY,AVERAGE AND WET CONDITIONS
Discharge Chum Spawning Area
Natural Filling Natural Filling Changesl/
Month.(cfs)(cfs)(sq.ft)(sq.ft.)(%)
Dry Year
August 17,392 8,000 185,588 64,581 -65.2
September 10 ,422 5,800 81,101 58,730 -27.6
Average Year
August 22,228 12,415 312,625 104,413 -66 •.3
September 13,221 6,800 116,359 60,244 -48.2
Wet Year
August 25,236 15,505 413,678 152,010 -63.2
September 15,124 6,800 146,939 60,244 -59.0
--11 Percentcnall.ge calcul~:i"t:ed as (HA filling";'1),x 100;wnere-HA-:ls the
spawning habitat area.HA natural
J
]
I
1
J
I
]
.j
._'J
1
)
I.)
]
j
I
J
Ii
I
1
TABLE E.3.2.66:ESTIMATED CHANGES IN CHUM SPAWNING HABITAT
AREA IN REPRESENTATIVE GROUP 3 DUE TO FILLING
UNDER DRY,AVERAGE AND WET CONDITIONS
Discharge Chum Spawning Area
Natural Filling Natural Filling Changesll
Month (cfs)(cfs)(sq.ft)(sq.ft.)(%)
Dry Year
August 17,392 8,000 191,364 44,927 -76.511
September 10,422 5,800 121,375 32,677 -73.1
Average Year
August 22,228 12,415 209,899 187,571 -10.6
September 13,221 6,800 190,242 36,992 -80.6
Wet Year
August 25,236 15,505 216,673 197,726 -8.7
September 15,124 6,800 198,044 36,992 -81.3
11 Percent change calculated as (HA filling -1)x 100,where HA is
the spawning habitat area.HA natural
TABLE E.3.2.67:ESTIMATED CHANGES IN CHUM SPAWNING HABITAT
AREA IN REPRESENTATIVE GROUP 4 DUE TO FILLING
UNDER DRY,AVERAGE AND WET CONDITIONS
Discharge
Natural Filling
(cfs)(cfs)
i
1
J
I
I
)
J
!
+78.4
+17.4
+49.3
-12.1
572,268
646,352
675,473
564,218
Chum Spawning Area
320,766
550,587
452,540
641,735
Natural Filling Changesl1
(sq.ft.)(sq.ft.)(%)
8,000
5,800
12,415
6,800
17,392
10,422
22,228
13,221
Month
August
September
Average Year
August
September
Dry Year
Wet Year
II Percent change calculated as (RA filling -1)x 100,where HA 1S the
---s pawrfing-JjaoitaE atea~~·~~---ID\~~t~r~l--------
August
September
25,236
15,124
15,505
6,800
253,424
504,165
495,117
646,352
+95.4
+28.2
,I
1
i
)
!
)
j
)
\
TABLE E.3.2.68:ESTIMATED CHANGES IN CHUM SPAWNING HABITAT AREA
IN AGGREGATE AREA OF REPRESENTATIVE GROUPS DUE TO
FILLING UNDER DRY,AVERAGE AND WET CONDITIONS
Chum Spawning Area
Natural Filling change sl1
(sq.ft.)(sq.ft.)(%)
Discharge
Natural Filling
(cfs) (cfs)Month
Dry Year
August
September
17,392
10,422
8,000
5,800
829,491
835,133
784,981
655,625
-5.4
-21.5
Average Year
August
September
22,228
13,221
12,415
6,800
850,543
857,189
865,253
743,589
+1.7
-13.2
Wet Year
August
September
25,236
15,124
15,505
6,800
883,744
849,148
844,854
743,589
-4.4
-12.4
II Percent change calculated as (HA filling -1)x 100,where HA is the
spawning habitat area.HA natural
TABLE E.3.2.69:PERIPHYTON GENERA EXPECTED TO COMPOSE THE
MAJORITY OF AUFWUCHS COMMUNITIES IN MAINSTEM AND
PERIPHERAL HABITATS WITH SOLID SUBSTRATES OF THE
SUSITNA RIVER,ALASKA l
Algal Classifications
Cyanophyta
Chlorophyta
Bad llario phyta
Genera
Nostoc sp.,Ca lothrix sp.,
Phomidium sp.,Lynghya sp.,
Nodularia sp.,Anabaena sp.,
Arthrospina sp.,Rivularia sp.
Spirogyra sp.,Zygnema sp.,
Ulothriz sp.,Hydrurus sp.,
Stigeoclonium sp.,Cladophora sp.,
Microspora sp.,Chaetophora sp.
Cymp§l1a sp.,Coconeis sp.,
Gomphonema sp.,Achnanthes sp.,
Meridian sp.,Navicula sp.,
Fragillaria sp.,Nitzschia sp.,
Diatoma sp.,other pennate diatoms
I )
I
,)'
I'~-
I
)
TABLE E.3.2.70 WEIGHTED USABLE AREAS AND HABITAT INDICES FOR JUVENILE CHINOOK
SALMON IN LOWER SUSITNA RIVER MODEL SITES.
RlI.L YCREEl /lOUrH CASIIEU.CREEk /IOUIH BEAVER Dllll SLOUGH
IlIllllSrEIl SHE .cHINOOK CHINOOk IlAIHSrEll SUE CHIHOOk CHIHOOK llAlHSrEIl SIlE CHIIlCOK 'ill NiJOk
DISCHARGE AREA"ll\lA H.I.DISCHAIl6E AREA IIIlA H.I.DISCiiAR6E AREA NUll H.I.
12000 B4901>3900 1).05 12000 111200 BOO 0.05 12000 11601i 1300 1).11
15000 B4900 3900 0.05 15000 16200 BOO 0.05 15000 111100 1300 0.11
18000 84900 3900 0.05 IBOOO 16200 800 0.05 18000 11600 1300 0.11
21000 B4900 3900 t.05 21000 111200 800 0.05 21000 11100 1300 0.11
24000 es3CO 3900 0.05 24000 111200 800 0.05 24000 11900 1300 0.11
27000 I830i 39M ....27.16300 lOG 0.05 27000 12200 1300 0.11
30000 moo 3tOO 0.04 30000 16700 1100 0.07 30000 12500 1300 0.10
33000 99800 4100 0.04 33000 moo 11100 0.09 UOOO 13000 1300 0.10
36000 108900 4200 0.04 36000 18000 2200 0.12 36000 13400 1300 0.10
39000 121000 4SOO 0.04 39000 18900 2700 0.14 39000 13900 1400 0.10
42000 13S000 4400 0.03 42000 19800 3200 0.16 42000 14400 1500 0.10
4SOOO 152600 4500 0.03 45000 21000 3700 0.18 4SOOO 15000 1800 0.12
41000 17BSOO 7300 0.04 48000 21800 4200 0.19 4SOOO 15700 2100 0.13
51000 198800 14101 0.07 51000 22701 4700 0.21 51000 16300 2600 0.16
54000 213000 20100 0.09 54000 23700 5200 0.22 54000 16800 3000 0.18
57000 223200 23400 0.10 57000 24600 5700 0.23 57000 17600 3700 0.21
60000 229800 25800 0.11 60000 moo 6200 0.24 60000 IIl500 4200 0.23
63000 235000 21000 0.12 63000 26300 6700 0.25 63000 19700 4600 0.23
66000 231700 30000 0.13 66000 27200 7200 0.26 06000 2ot1OO 4800 0.23
69000 2411100 31500 0.13 6mo 27900 7600 0.27 69000 21600 5000 0.23
72000 243200 32800 0.13 72000 .2BnO IJOOO 0.28 72000 22100 5100 0.23
75001 2436eO moe '.14 750tt 2me ....••21 75000 22600 5'200 0.23
IIOIIl.lliM SIll CIIMIIEL kllOlO SLOUIiIt IlEAl 8EARlA1 I SI~CIlAlIIlEl.
ItAllSrat SITE CHINOOI D111llll11 1IAIllS fEJI SITE D111ll1l1K CHIIIQOK IIAIIlSTEIl SITE.CHIHQQt.tHlHOllk
DlSC1lA1t6E AREA IIUA IL.I.OISCHAll&E MEA llUA It.I.DISCHARGE tlIiEA lIUA H.I.
12000 63400 500 0.01 12000 41200 100 .00 120tl0 310(1 20 0.01
15000 63400 500 0.01 15000 411200 100 .00 15000 31tlli 2,)u.iJ!
18000 63400 500 MI 1BOOO 48200 100 .00 1B1.'W 31f)i/Z('.)••)1
21000 63400 500 0.01 211100 48::00 "lfI .00 21VOV 31IJQ 20 0.01
24000 79800 7600 0.10 24000 48200 100 .00 241i00 3HJ(J 21i IMII
27000 86900 noo O.OB 2701)0 48200 100 .01;27000 310&2\:iI.1l1
30000 90800 6700 0.07 30000 48200 100 .00 30000 3100 20 iI.ill
33000 96S00 6100 0.011 33000 48:100 100 .00 33000 3100 20 0.01
36000 104800 510 0.05 36000 51'100 2700 0.05 36000 5700 200 0.04
39000 113700 490t 0.04 39000 61'100 4800 0.07 39000 10&00 350 0.03
42000 122900 4200 0.03 42000 77500 11200 0.01 42000 14600 530 0.04
eooo 131SOO 3600 1.03 4900 IU:IOO 7300.0.01 4SOOO 17900 6SO 0.04
48000 141200 2900 0.02 41000 95100 8100 0.09 4BOOO 21100 720 0.03
51000 152000 2200 e.Gl 51000 102200 7900 0.011 51000 moo 790 0.03
54000 163000 2000 0.01 54000 106700 6900 0.06 54000 26400 BOO 0.03
57000 174100 2000 e.ol 57000 110200 l1OOO 0.05 57000 29000 150 0.03
60000 186llOO 1901)0.01 I10OOO 113500 5100 0.04 60000 31500 700 0.02
63000 200800 1800 0.01 113000 lll1iOO 4300 0.04 63000 33900 6SO 0.02
6l1OOO 213300 1800 0.01 66000 119000 3400 0.03 6/1000 36300 610 0.02
69000 22IIOGO 1800 0.01 119000 120100 2'100 0.02 119000 31300 590 0.02
"nooo 231000 lllOO 0.01 72000 121000 2500 0.02 72000 40000 570 0.01
7SOOO .2S09OO 1BOO O.Gl 75000 121400 2200 G.02 15000 41500 5110 0.01
SOURCE:ADF & G 1985c
TABLE E.3.2.70 (Page 2 of 3)
I LAST CIlAlICE S.t.RUSJ1t IIILDERNESS S.t.ISI.AIID SIIl€tllANII£l.
.1
·MIIISTEII SITE tHlllOlIK tHlNllOl MIII5TEII SItE tlIll100K tlIllll1l11C MIIISTEII SITE tHlNlD tHllIOOl
8IStHAR6E A\l£A lIIIA H.I.IIStlIAIIliE AR£A !lUA H.I.DISCIWl6£MEA lIllA H.I.
12000 17500 110 t).t)1 12000 4809 30 0.01 12000 31500 400 0.01
'I15000175001100.\11 lSOOO 4900 30 0.01 1'000 31500 400 0.01
IBOOt)17500 '110 0.01 18000 4900 30 0.01 18000 moo 400 0.01
21000 17500 110 0.01 21000 31'100 4800 0.15 21000 31500 400 0.01
24000 moo 110 0.01 24000 49300 5100 0.10 24000 moo 400 0.01
27000 S1700 200 0.01 27000 60700 4300 0.07 27000 SI500 400 0.01
30000 50600 370 0.01 30000 69700 3700 0.05 30000 31500 400 1),01
33000 113900 540 0.01 33000 76800 3000 0.04 33000 SISOO SOO 0.02
36000 moo 700 0.01 36000 83300 2400 0.03 36000 44600 3500 0.01
39000 BOOOO 900 0.01 39000 B9900 1900 0.02 39000 411100 4800 .0.10
42000 11590I 1030 0.01 42000 97000 1500 0.02,42000 53200 4100 0.01'
45000 V0600 1220 0.01 45000 104000 1200 0.01 4SOOO SItOO 3400 0.011
48000 94000 1520 0.02 48000 109000 900 0.01 48000 6SSOO 2900 0.04
51000 96300 1990 0.02 51000 114000 700 0.01 51000 72000 2400 0.03
54000 98500 2560 O.OS 54000 117400 500 .00 54000 79400 2100 O.OS
57000 100200 2620 0.03 57000 119200 500 .00 57000 16700 1100 0.02
...6OCOO ··'101800 .·2540 0.02 60000 120700 600 .00 ·60000·93100 1700 0.02
1130OO 103200 2460 0.02 113000 121700 600 .00 63000 99800 1100 0.02
66000 104400 2350 0.02 66000 122200 600 .00 66000 106200 2100 0.02
69000 105SOO 2240 0.02 69000 122700 700 0.01 69000 lU900 2400 0.02
72000 186300 2100 0.02 12000 123000 700 0.01 72000 118200 260e 0.02
1SOO8 107.1900 G.t2 75000 I2350G 800 0.81 7soee 123308 2700 o.e2
..11II111I lIUT IlIlIII ..2 1111 CIMIL ~llIQlLAIl Sill ClIME.
lIA'dB !lITE tltl....DlJ....MIII5TE11 SIIE ptlllOlll(CItIIlllOl MIIISTEli SITE tlIlrm DlUlIlIIIC !:HAR8E IlEA lIIIA II.'J.IlstIWlGE AIIEA lIIIA No I.IISCIIAR&E AIlE,lIIIA H.I.
.2000-61603 1012 0.02 12000 0 0 0.00 12000 594114 747 0.01
5000 61603 1012 0.02 lsooe 0 0 0.00 15000 59464 747 0.01 .)........·,8000 61603 .1082 0.02 ..--18000..0.._L.,_0.00 ............J8000_594ol._...741 ,0·9.1
!IOOO 73426 10041 0.14 21000 0 0 0.00 21000 5941a4 74'~fli..,.__._--~_._--------,"'---!4000'80904-'832:5'---0~1O '24000'r''0'"'0;00 ·...··24000--5fl404--747 -O;OJ'
t7000 933S'S 5224 0.06 27000 0 0
0.00 27000 59464 747 0.01
30000 108613 4045 0.04 30000 9600 1500 0.16 30000 59464 747 0.01
S3000 U4738 3959 0.03 :s3OOO 215M 2900 0.13 33000 59464 747 0.01
36000 117696 3161 0.03 36000 34300 4000 0.12 36000 71590 1717 0.12
moo 120505 S775 0.03 39000 47800 5100 0.11 ·39000 76534 &404 0.11
42000 123S97 J85S 0.03 42000 61400 6100 0.10 42000 eoss7 BOIS 0.10
45000 129211 4113 0.03 4SOOO 72000 6'100 0.10 45000 15140 7472 '.09
41000 13364'4630 '.03 4lIOOt 81400'~"7000 '.09 4lIOOO 92944 7077 0.01
51000 13l181S 5011O 0.04 51000 moo 6700 0.08 51000 102S30 6998 0.07
$4000 140161 5554 0.04 "-_....--54000 93200 ..6000.0.06 54000...113m ....69911 0.06
57000 144269 6217 0.04 57000 97100 4600 0.05 57000 12S753 61134 0.05
60000 147m '728 0.05 60000 99900 3100 0.03 60000 1342111 6516 0.05
1130OO 151842 7092 0.05 113000 102000 2700 0.03 63000 143575 6906 0.05
66000 154205 75911 0.05 66000 103200 2400 0.02 66000 IS0869 7926 0.05
6'1000 156425 7913 0.05 69000 104200 2100 0.02 69000 134657 11561 0••'72000 IS8S22 8078 0.05 72000 104800 1110O 0.02 72000 157074 11I4O 0.011
7SOOO 160818 843B 0.05 75000 105loe 1600 0.02 7SOOO 159211 lIlIS4 0.06
\
\
\
.1
TABLE E.3.2.70 (Page 30f3)
SAUIM SIDE CllAIIIlEL SlICl£R SIDE CIIAIIEL -:.,8€AV£Il IlAII SIDE CHANliEL
MIIiSIEII SITE CHINOII*:CHIIlIllll IlAIIISIEII SITE C11111OO1 CHIIllIlIIl IlAIIlSI~SITE CKIIIOOK CHIHOOr..
DISCHAR&E AREA IIlJA K.I.DISCIIAR6E MEJ;IIlJA H.I.DISCHllR6E AREA HIlA H.1.
12000 42093 165 .00 12000 0 0 0.00 I~18900 ~"IlO
15000 42093 165 .00 15000 0 0 0.00 15000 18,00 50 .00
18000 42093 165 .00 18000 0 0 0.00 lllOOO 18900 50 .00
21000 42093 165 .00 21000 0 0 0.00 21000 IB900 SO .00
24COO 47093 115 .00 240c0 .0 0 0.00 24000 18900 SO .00
2700u 42093 165 .00 27llOi 1600 0 0.00 27000 18900 50 .00
30000 42093 165 .00 30000 IISOO 1060 0.12 30000 IB900 50 .00
33000 47611 5470 0.11 33000 14900 1600 0.11 33000 lam 50 .00
36000 48790 S7l3 0.12 36000 111900 1570 ••09 36000 18900 50 .00
3..49127 sm 0.12 moo .,.1510 '.01 39000 11900 ~.00
42000 4mI 5740 0.12 42000 23600 1450 0.06 42000 18900 50 .00
45000 ~289 5303 0.11 4900 29600 I~O 0.05 45000 19900 50 .00
41000 50889 4980 0.10 41000 37100 2070 0.06 ,48000 22400 820 0.04
:51000 51451 4470 0.09 51000 4WO 2940 0.06 51000 21000 2370 0.08
54000 52011 ~0.08 54000 moo 4230 0.07 54000 32600 3560 0.11
57000 52678 ~5 0.07 57000 66900 4680 0.07 57000 35700 3840 O.ll
60000 53294 3365 0.06 60000 moo 4490 0.06 110000 38000 3570 0.09
1130OO 54275 311.0.0'63000 milO 4230 0.06 Ii3000 39600 30110 0.09
11IIOOO 55184 2947 0.05 66000 moo 3940 0.05 66000 40800 2510 0.011
119000 56053 2757 0.05 119000 'moo 31110 0.05 119000 41500 2260 0.05
72000 57142 2671 0.05 72000 71100 3270 0.04 72000 41900 2100 0.05
75000 IIItll 2714 1.04 75000-mot 3010 0.04 75000 42100 2000 0.05
;~'.:;J?""
.-0 SIDE QIIIIlIIEI,..lSI:SIDE ciMEL ......;....l'W'O CJUl S.C•
IIAIIlSIEII SITE CHIIIIOK CltINOOK'IlAINSIEII SITE CltIIlOOl CHIIlllOK IlAlllSTEII SIlE C11INOOt.CHllIOOl
DISCIIAII6E AIlEA IIIlA H.I.DI!iClIM6E AIIEA WII H.1.'DISCIIAIIS£AREA HUll H.I.
12000 495112 561 0.01 12000 0 0 0.00 12000 73300 1100 0.02
15000 49562 568 0.01 15000 0 0 O.~O 15001)moo 1100 0.02
18000 49562 568 0.01 18000 0 0 0.00 lBOi/O moo 1101)O.O~
21000 4"112 561 0.01 21uOO 0 0 O.Oti 2111Oi/i3301i llW Ii.02
24000 49562 5'8 0.01 24000 0 0 0.00 24000 moo 1100 0.112
27000 MU8 3928 0.06 27000 0 0 0.00 2JOW mOil ll11ti 0.02
:soooo 69129 4091 0.011 30000 I)0 0.00 JOOOO 73300 1100 001>2
3JOOO 71488 4311 0.011 33000 •0 0.00 33000 73300 1100 0.02
3lIOOO &9472 4420 0.05 3110OO 19000 1110 0.03 36GOO 75600 2000 0.03
39000 mu 41130 0.05 3900.moo 3250 0.06 39000 1l51UO 9100 0.11
42OGO 106320 4984 M5 42000 7COO 51160 0.07 42000 97100 8300 0.09
«10M lm3I 5436 0.04 '45000 97100 '6090 0.06 45000 101700 7100 0.07
4MOO 1354711 ~0.04 48000 115400 4270 0.04 48000 119100 5700 0.05
51000 149241 5IhI 0.04 51000 I~Uoo 3820 0.03 51000 128900 4000 0.03
54tOO 165990 5768 0.03 S4000 146900 3540 0.02 54000 137400 2700 0.02
57000 173483 5417 o.o~57001.l6060t 3250 0.02 57000 14J300 IBOO 0.01
IIGOOO 111m 5931 0.03 60000 175600 3180 0.02 60000 148800 1300 0.01
lI3000 194419 6000 0.03 6Joeo 192000 34110 0.02 63000 154800 1300 0.01
6'000 203000 6231 0.03 611000 207300 3760 0.02 6110OO 160700 1300 0.01
69000 2011972 UII3 0.03 119000 221400 4080 0.02 119000 111II100 1300 0.01
72000 210728 11157 0.03 12000 229000 4l'IO 0.02 72000 169800 1300 0.01
15000 215861 5&48 0.03 75000 233300 4210 0.Q2 75000 172bOO \300 0.01
TABLE E.3.2.71:SUMMARY OF EFFECTS OF STAGE I FILLING FLOWS
ON JUVENILE CHINOOK REARING HABITATS
IN THE LOWER SUSITNA RIVER FROM TALKEETNA TO COOK INLET
I
Site Name May June July August September October
Rolly Creek Mouth 0 0 0
Caswell Creek Mouth 0 0
Beaver Dam Slough 0 0 0
Hoologan Side Channel +++++++0
Kroto Slough Head 0 +++0 0 0
Bearbait Side Channel 0 0 +0 0
Laet Chance Side Channel 0 +0
.1RueticWildernessSideChannel+0 ++++0
Island Side Channel 0 ++0 ++0 0
Mai nstem··West Bank ++0
Goose 2 Side Channel 0 +++++++0
Circular Side Channel 0 0 +0 0
Sauna Side Channel 0 +++++0
Sucker Side Channel 0 ++0
Beaver Dam Side Channel 0 ++0 0
Sunset Side Channel 0
Sunrise Side Channel 0 ++++0 0
Trapper Creek Side Channel 0 ++++++++0 0
-----------------------------------------------------------------------------------------------
.!
I
TABLE E.3.2.72:SUSITNA HYDROELECTRIC PROJECT
FEATURES OF NAMED TRIBUTARIES
IN THE STAGE I WATANA RESERVOIR AREA1/
Tributary
Susitna
River
Confluence
(River Mile)
Total
Length
Affected
(mi)
Stream
Gradient
(ft/mi)
Approximate
Length in
Drawdown
Zone
(mi)
Approximate
Length
Permanently
Inundated
(mi)
Deadman Creek 186.7 2.0 253 .6 1.4
Watana Creek 194.1 7.5 60 2".5 5.0
Kosina Creek 206.8 2.8 118 1.3 1.5
Jay Creek 208.5 2.1 143 1.0 1.1
1/Stage I Watana River Surface Elevation:2000 ft.MSL
Source:Adapted from ADF&G 1983b
TABLE E.3.2.73:MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS
AT GOLD CREEK (CFS)DURING STAGE I OPERATION
Natura 1 Conditions Stage I Flows
Month Max Min Mean Max Mean Min
Oct 8,212 3,124 5,825 9,958 5,124 7,903
Nov 4,192 ·1,215 ·2,578 9,519 4,686 7,800
Dec 3,264 866 1,828 11 ,420 5,922 9,120
Jan 2,452 724 1,524 9,529 5,181 8,135
Feb 2,028 723 1,309 8,490 5,175 7,591
Mar 1,900 713 1,173 6,677 4,050 5,732
Apr 2,650 745 1,441 5,292 2,830 4,108
May 21,890 3,745 13,483 10,186 5,012 6,380
Jun 50,580 15,500 27,795 16,736 8,470 13,324
Jul 34,400 16,100 24,390 23,575 8,045 14,492
Aug 37,870 8,879 21,911 35,192 8,251 18,276
Sep 21,240 5,093 13,493 20,028 7,027 14,230
Annual 11,961 5,596 9,781 12,004 6,594 9,774..
\
J
I
1
I
I
'1
I
I
I
I
.1
l
I
I
I
)
.-j
TABLE E.3.2.74:TOTAL CHINOOK R~ARING HABITAT AREA
IN ALL REPRESENTATIVE GROUPS
DURING SUMMER WEEKS UNDER
STAGE I FLOW REGIME
Stage I Flows Natural Flows
---------------------------------------------------------------;
Calendar
Week
Total Habitat Area Exceeded
90%50%10%
Percent of Time
Total Habitat Area Exceeded:
90%50%10%
Percent of Time
(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
22 5171857 5771260 6055777 5887756 6131097 6843402
23 5668626 5929310 6250932 5476820 6222510 6893240
24 5725980 6161086 6258065 3494928 6151734 6780969
25 5767946 6195761 6251396 5218277 6187294 6840933
26 5850003 6206316 6256064 595846::-6372627 6892074
27 5795649 6187609 6260385 5960915 624544::-6836489
28 5795575 6186~578 6259993 6963999 6108808 6790478
29 5706604 6209704 6261246 5954151 6240076 6873055
30 5712567 6077043 6321585 59715~58 6137691 6847559
~;1 5769172 6212813 6799170 5517503 6294162 6815705
:::',2 5738414 6177955 6593384 5954772 6171091 682::-350
33 5306173 6078478 6246680 4956682 6063121 6376799
34 5722170 5994016 6260493 5561034 6096961 6376799
35 5727~?22 6064021 6259540 5517503 6138112 6292156
36 5707805 6012659 6316796 5685606 6000258 6316496
37 5715499 6015482 6255674 5690184 6008042 6228691
38 5700721 5993625 6255846 5292193 5960600 6259540
39 5707155 6033980 6248407 4987661 5809273 6216278
---------
Calendar Week 22 =Week Beginning May 27
i
TABLi
I
I
,
!E.3.2.75:
1
TOWAL CHINOOK REARING HABITAT AREA
IN!REPRESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS UNDER
STAGE I FLOW REGIME
4721533
4718252
4720054
4543200
4449608
4488465
4581977
4220266
4230208
4258885
4245477
4240463
4181791
423040l
4496151
4629213
4712545
4734924
4528447
4450270
4504139
4332384
4398222
4125226
4124438
4071885
4076823
4113942
4119204
4125798
4091048
4137456
4101473
4138079
4171382
4176297
2335020
385313:::'~
4145T16
4116902
3976770
3966421
3449123
4039301
3140204
4040200
40~':;7705
4096153
3284299
3828240
3853137
3426713
4025392
4151235
4740480
L~717551
4728496
4735962
4 1734032
41727844
4j738400
41719153
~732680
4174~$006
4744736
4j741::;95
4j746239
~7412l669
4738638
41735541
4703242
4712545
4476442
4662600
4613678
4634967
4661693
4658602
4660950
4461505
4546587
4224526
4279622
23
33
35
24
26
27
25
39
36
37
38
34
22
32
29
312l
31
iI !
----------------------I-~----·_---------------------------------------------------I Stage I Flows 1 Natural Flows
----r-r-------------~------------------------------------------1
Totai kabitat Area E~ceeded 1 Total Habitat Area Exceeded 1
Calendar I 9~~50%10%I 90%50%10%
Week 1 I'Percent of Time 1 Percent of Time
--------~~~-----------r-r~------------:-------------------------------------------
(sql f [t ) (sq f t)Osq f t )(sq f t ) (sq f t )(sq f t )
I '
424~9145
1 i
432r-1,814:71:~42 ~~
4~?~06?455~~8'441 11 ~65 ko_0-
443b3:64
424181194
1 ,
407f39f57
4(l)317~94
404i7213
4 12l4!0 cJ95~~~1""7!j 6•.:.....:.....:...1..::.!.
40~0~00 4322421
403i77i05 439610441~57t89 4420596
416~a06 4540606
417j2012 4552071
42~4~32 4597813
Calendar Week 22 =We~k iBeginning May 27
~,--'-~'--
1__--.i..
.---~._.------~--_..._~---~-
._~---~~._-----~---"-----_.---'-...-._---'~._~-_..~~~
TABLE E.3.2.76:SUMMARY OF ACCESS CONDITIONS FOR THE CHUM SPAWNING SITES (Page 1 of 4)
DURING STAGE I OPERATION BASED ON MEAN AVERAGE MONTHLY
FLOW,MAXIMUM AND MINIMUM AVERAGE MONTHLY FLOWS
River Mile Represen-Nat ral Discharge Stage I Flow Re ime
Designa-tative Passage Maximum M an Min'mum Maximum M an Minimum
Site Name tions~/Groups Reach.!:/Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep
Whisl er's Creek 101.4L 2 I _c/- - ------- -
-
Sl<ugh II --- ---- -
-- -
-
Main tem II 115.0R 3 I siY S S S SiD U S S S S U U
II S S S S U U S S S S U U
III - -
- - - -- -
----
IVL -- - - - -
- -----
2 IVR S S S U U U S S U U U U
VR - - -
-- -
- - -- -
-
VIR --- ---- - --- -
VIIR ---- -
- -- -- - -
VIIIR -- ---- - -- - -
-
Slou h SA 126.0R 2 I S S S S S U S S S S S U
II S S S U U U S S S U U U
III S S S U U U S S SiD U U U
IVL S U U U U U S U U U U U
IVR ----- -- - -
---
VR -- -
---- -
- - --
VIR - - -- ---- -
-- -
VIIR ---- --------
VIlIR - --- --- - - ---
IXR -- -- -
- -
- -- - -
XR -------- - ---
TABLE E.3.2.76 (Page 2 of 4)
River Mile RePf e 4en-Natural Discharge Stage I Flow Re ime
Designa-tative Passage Maximum.M an Minimum Maximum M an Minimum
Site Name.tions~1 Grbups Reach~/Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.i '
Slough 9 128.8R 3 I S S S S U U S S S S U U
II ---- -
- - --- --
III -----------,
IV T - - ----- -
---
V I --- -
----- - -
I·
Slough 9A 133.8R 1 I S S S S U U S S S S U U,
II I ---- -------
III I ----- - -----
-IV I ---- - - -- -
--
V r ------- ----
VI T ----- ------
VII r -- --- -
-----
VIII I -----------
Xl - -
- - -
------
X T"-----------
Xl i"- -
- -
-------
Side Channel 10 133.8L !SID6IS S S U U U S S U U U
II !-- - - -
------rIIIr --- -
- ------
IV r --- --------
V i"--- -
--- ----
VI T ------- -
- --
i
r··.__'_.S-.---.
'--_..-.--
TABLE E.3.2.76 (Page 3 of 4)
River Mile Represen-Natural Discharge Stage I Flow Re ime
.Designa-tative Passage Max "mum Mean Min"mum Maximum M an Minimum
Site Name tions~.1 Groups Reach~1 Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.Aug.Sep.
Slou/h 11 135.6R 1 I S S S U U U S S S U U U
II S S S U U U
S S SiD U U U
III S U U U U U S U U U U U
IV U U U U U U U U U U U U
V - -- ------- -
-
VI --- -- ---- -
--
VII - -
---- -
-- -
--
Uppel Side l36.3R 6 I -- - -
---- - -
--
Cl annel 11 II -- - -- - -
- -- - -
Slou~h 19 139.7R 5 I - - - ---- -
- - - -
.II - - - -- - --- ---
III -- -- -- - --- - -
IV ----- - -
- ----
V -- - -
- - - - - -- -
139.9R 1 VI S S S S U U S S S U U U
VII S S S U U U S S S U U U
VIII S S S U U U S S SiD U U U
Xl S U U U U U S U U U U U
Slou~h 20 l40.2R 2 I S S S S U U S S S S U U
II S S S U U U S SiD U U U U
III --- ---- -
----
IV ----- -
- - ----
V - -----------
VI -- --- - -- - - --
TABLE E.3.2.76 Page 4 of 4)
Side Channel 21 141.4R
Site Name
Slough 21
Slough 22
River Mile
Designa-
tions~/
141.6R
142.1R
144.4L
Rep~eJen-
I !ta~ive
GroupsI,
3
5
2
2
Stag I Flow R pme
Passage Maximum Mean Minimum
Reach.~/Aug.Sep.Aug.Sep.Aug.Sep.
,
I S S S
S S U S S S S S UI
II ~S S S
U U S S S
S U U
III T --- - --- -
-- -
IV T - - - -
-- - -
---
V I -- ------ ---TVIT -- -- --- - ---
VII T -.-- - -
----- -
VIII i'"- - - -
-- -
- -
--
!IX T ---- - - - -
-.-.-
I I - - - -
---- -
--rIII --- - -
-- -
---TIIlLr --- - - - -----
IIIR r --- - - - - -
-- -
I
I I~I ;/DI ~I~I~I;I~I~I~I~I ~I SIIIS
III ~
dl U =Unsuccessful condition,SVD =Successful W1
was no ~valuated since b
backwa er influence.
al
'01cl
Source:EWT&A and AEIDC
Source:ADF&G 1985
Influence of backwater
required for providing
1985
1
ching flow occurs at discharges lower than those
Difficulty and S =Successful.
TABLE E.3.2.77:TOTAL CHUM SPAWNING HABITAT
IN IFG AND DIHAB MODEL SITES
DURING SUMMER MONTHS
UNDER STAGE I FLOW REGIME
Caletndar
vJaek
Stage I Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Pet-cent of Ti me
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Pet-cent of Ti me
(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
32 71996 74257 86129 72935 74117 76821
33 40810 74173 86365 35061 73755 78712
34 46690 74944 85791 45002 74129 84101
35 46690 76725 85363 44286 76030 85363
36 56390 80021 86493 47448 75257 86202
37 51134 83756 87201 47448 76554 85219
38 52687 84683 87218 36322 74376 86928
39 47070 84763 87136 26285 62440 86438
Caldndar Week 32 =Week Beginning August 5
i i
i I
i jTABLEE.!3.!2.78:TOTAL!CHUM SPAWNING HABITAT AREA
IN RE~RESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS UNDER
STAGE!I FLOW REGIMES
,,i.
iii
------------~----------~~~~~-~-;~~:-~~~~~+-------~---------~~~:~~~-;~~:-~~~~~:------------
Modelled Habitat Area Exceeded I Modelled Habitat Area Exceeded
Calendar 90%1 '50%10*I 90%50%10%
Week P~rcent of Time'I I Percent of Time____________~------------J-~-------------~------------~_
(sq ft)!(sq ft)
,
(sq oft)(sq ft)(sq ft)(sq ft)
'-~-
i
i32826534 855238 879186 826654 849978 883525
33 398113 ,847968 866300 330883 832670 858434
iii3478498~.836728 869498 689191 836728 862500,i
35 78498~851962 868158 620955 852626 868158I'
36 823765 !856520 868428 789790 840645 866908
37 805035 I 851897 868813 789790 840943 864098
i 'I38810568!855986 868130 729972 844361 867598
39 787395 !859769,8687
1
5",8 608728 825264 865603
..i I-------------------------1-1-------------1------------------------------------------------
Calendar Week 32 =Week Beginning August 5,I 'I ','1
"1
~
,_i__
TABLE E.3.2.79:TOTAL CHUM SPAWNING HABITAT
AVAILABLE FOR INCUBATION OF EMBRYOS
IN IFG ANDDIHAB MODEL SITES
UNDER STAGE I FLOW REGIME
..--------------------------------------------------------------------------------------
Cal~ndar
W~ek
Stage I Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Percent of Time
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Percent of Time
(sq ft)(sq ft)(sq H:)(sq f"U (sq ft)(sq ft)
40 36757 81940 86899 21116 4478:::'~80392
41 30653 44796 52392 19923 38552 49157
42 21554 39025 47219 15404 21348 42731
43 20326 40891 47516 11066 20021 29479
44 21266 4:::::849 48178 8127 16393 21148
45 25117 47100 48187 7586 13242 19511
46 29616 44569 51107 7112 12294 16391
47 34075 46971 56224 6230 11547 15172
48 38842 47841 49004 5552 10872 14053
Cal~ndar Week 40 =Week Beginning October 1
---------------------_._---~-~~-~----------~-----------------------------------------------
,
•I.TABLE E.=f.2.8Q.):
1
ITOTALCHUM SPAWNING HABITAT
IINREPRESENTATIVE GROUPS 2,3,AND 4
AVAILA~LE FOR INCUBATION OF EMBRYOS
DURINGI EARLY WINTER WEEKS UNDER
STAGE [FLOW REGIMES
Calendar
Week
Stage:I Flow Regimel
ModelledlH~bitat Area Ex~eeded
9Q.)%i I 50%10%1
Percemt of Ti me
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Percent of Time
838855
866409
877949
9338Q.)Q.)
807872
754469
762341
788863
812041
857300
739687
676018
723848
761343
797933
821592
850131
819360
684023
605669
457804
414471
446820
513934
585116
649601
71078Q.)
44
45
40
41
46
47
48
42
43
--------------------------t-,----·--~------I-----------------------------------------------
(sq ft)I 1(sq f t )(sq f ft )(sq f t )(sq f t )(sq f t )
I ,
1 i I7331Q.)41 :863614 8693~7
6891231 776995 8Q.)9517
5216341'i 749444 7889V.'2
502494 .:760530 7902:26
5171461 I 773Q.)01 7944129
5872231 '787586 794~86
67Q.)0291 I 776037 8049140
713782 i 7j867658231175
7481231 i 792285 7974146
i ,
, I t
------------~~------------~~---------~~--~------------------------------------------------
Calendar Week 4Q.)=Week Bepi1nnin g October 11
---'
TABLE E.3•2•81 :SUSITNA HYDROELECTRIC PROJECT
SIMULATED STREAM TEMPERATURES
STAGE I
WEATHER PERIOD:SUMMER 1981
CASE E-VI
FLOW REQUIREMENTS
STAGED CONSTRUCTION
RIVER MAY JUNE JULY
MILE 31 32 33 34 35 36 37 38 39 40 41 42 43 44
18411 2.2 2.8 3.8 4.8 6.6 8.1 8.8 10.3 9.5 8.4 8.4 10.2 10.5 10.5
173 2.5 2.8 3.5 4.7 6.4 7.7 8.8 10.3 9.4 8.4 8.4 9.9 10.4 10.4
162 2.8 3.6 4.2 5.3 7.0 7.9 9.1 10.6 9.6 8.7 8.6 10.1 10.6 10.5
150 3.1 3.7 4.2 5.4 7.1 7.9 9.3 10.8 9.7 8.9 8.7 10.1 10.7 10.7
140 3.3 3.9 4.3 5.5 7.2 7.9 9.4 10.9 9.8 9.0 8.8 10.1 10.7 10.7
130 3.6 4.3 4.6 5.8 7.3 7.8 9.4 10.9 9.6 9.0 8.6 9.8 10.4 10.5
120 4.0 4.9 5.3 6.4 7.9 8.1 9.8 11.3 9.9 9.3 8.9 10.1 10.7 10.7
110 4.3 5.5 5.8 6.9 8.4 8.3 10.2 11.6 10.1 9.5 9.1 10.3 11.0
10.9
992:.1 4.7 6.0 6.4 7.4 8.8 8.6 10.5 11.9 10.4 9.7 9.3 10.6 11.2 11.2
9all 4.4 5.7 6.2 6.7 7.7 7.0 8.5 9.4 8.5 8.5
8.2 8.6 9.0 9.3
84!±1 4.8 6.4 7.1 7.4 8.5 7.5 9.2 10.1 9.0 9.0 8.7 9.1 9.5 9.8
RIVER AUGUST SEPTEMBER OCTOBER
MILE 45 46 47 48 49 50 51 52 1 2 3 4 5
18411 9.7 9.1 8.3 9.2 8.8 7.9 8.0 7.1 6.1 5.1 4.8 4.3 3.7
173 9.8 9.1 8.4 9.2 8.8 7.8 7.9 6.9 5.7 4.7 4.1 3.6 3.0
162 9.9 9.1 8.5 9.4 8.9 7.9 7.9 6.7 5.4 4.5 3.8 3.3 2.5
150 10.1 9.3 8.7 9.5 9.0 8.0 8.0 6.7 5.3 4.4 3.6 3.1 2.2
140 10.2 9.3 8.8 9.6 9.1 8.0 8.0 6.5 5.1 4.2 3.4 2.9 1.8
130 10.2 9.2 8.8 9.6 9.0 7.9 7.9 6.3 4.9 4.0 3.2 2.6 1.4
120 10.4 9.3 8.9 9.8 9.2 8.0 7.9 6.2 4.7 3.9 3.1 2.5 .9
110 10.5 9.3 9.0 10.0 9.3 8.1 8.0 6.1 4.7 3.8 3.0 2.4 .5
992:.1 10.7 9.4 9.2 10.2 9.5 8.2 8.0 5.9 4.4 3.7 2.9 2.3 .1
9all 9.3 8.2 8.3 8.7 7.9 7.2 6.7 4.7 3.6 3.2 2.7 2.1 .1
84!±1 9.7 8.2 8.6 9.3 8.2 7.3 6.8 4.3 3.4 3.1 2.6 2.0 0.0
11 Downstream of Watana Damsite
2:.1 Upstream of Chulitna-Susitna confluence
j
11 Downstream of Chulitna-Susitna confluence
!il At Sunshine stream gaging station
TABLE E.3.2.82:SUSITNA HYDROELECTRIC PROJECT
SIMULATED STREAM TEMPERATURES
WEATHER PERIOD:SUMMER 1982
2001 ENERGY DEMANDS
CASE E-VI FLOW REQUIREMENTS
STAGED CONSTRUCTION
STAGE I
RIVER MAY JUNE JULY
MILE 31 32 33 34 35 36 37 38 39 40 41 42 43 44
18411 2.6 2.7 2.9 3.2 3.7 5.2 6.3 6.6 8.7 10.9 10.6 9.9 9.9 9.4
173 2.9 2.5 2.6 2.9 3.7 5.1 6.2 6.7 8.7 10.8 10.6 10.1 9.8 9.6
162 3.4 2.9 3.3 3.4 4.3 5.5 6.4 7.1 9.1 11.0 10.8 10.4 10.0 9.9
150 3.6 3.0 3.4 3.5 4.5 5.6 6.5 7.3 9.3 11.0 10.9 10.6 10.2 10.1
140 3.8 3.0 3.5 3.6 4.7 5.7 6.6 7.4 9.4 11.1 11.0 10.8 10.2 10.3
130 4.2 3.3 3.7 3.8 4.9 5.8 6.6 7.5 9.4 10.9 10.8 10.7 9.9 10.1
120 4.7 3.7 4.3 4.3 5.4 6.2 6.9 7.9 9.8 11.2 1l.2 11.1 10.1 10.5
110 5.2 4.0 4.8 4.8 5.9 6.5 7.1 8.2 10.2 11.5 11.4 11.4 10.4 10.8
992)5.7 4.4 5.3 5.2 6.4 6.8 7.3 8.5 10.6 11.8 11.7 11.7 10.6 11.2
981/5.2 4.3 5.2 5.3 6.2 6.7 6.5 7.2 9.1 9.2 9.0 9.3 8.3 9.0
841.1 5.6 4.7 5.9 6.0 7.2 7.7 7.0 8.0 10.1 9.7 9.6 10.0 9.0 9.8
RIVER AUGUST SEPTEMBER
MILE 45 46 47 48 49 50 51 52
.__.....•.-.-_.__...._.•.__-.
18411 9.8 9.4 9.9 9.2 9.3 9.6 8.4 7.3
173 10.0 9.6 10.0 9.3 9.1 9.2 7.9 6.9
162 10.2 9.8 10.2 9.4 9.2 9.2 7.9 6.8
150 10.5 10.0 10.4 9.6 9.2 9.2 7.8 6.8
140 10.7 10.2 10.6 9.7 9.2 9.1 7.8 6.7
130 10.6 10.2 10.6 9.6 9.1 8.9 7~5 6.5
120 11.0 10.5 10.9 ·9.9 9.2 9.0 7.6 6;4
......-.--.--.··--·_-110--·.--11.-3-1 0.-7-H.-L-10;1-··9.-3-··9 .-0··7.-6-·-6.4---.
..-..-----..------·9-92:.1.-1-1-.-7-11-.·0-1-1-.-4·....,.10-•.,3--9-0'4--9-.-1-.·7-.-7--6-.,4-_·_.
9811 9.2 8.7 9.2 7.9 7.8 7.2 5.7 5.3
84£t/9.8 9•3 9•8 8.5 8.0 7•2 5.9 5 .1
11 Downstream of Watana Damsite
2:.1 Upstream of Chulitna-Susitna confluence
11 DowIlstream ...o.fChulitIla....Stil3itnaconUtience
~I At Sunshine stream gaging station
1
)
.1
j
1
1
1
I
-1
1
1
(
-I
.1
I
1
l
1
TABLE E.3.2.83
STREAM TEMPERATURES
WEATHER PERIOD:SUMMER 1981
NATURAL CONDITIONS
WATER ·.WEEK NO.
River May June July
Mile 31 32 33 34 35 36 37 38 39 40 41 42 43 44
1841/4~8 7.6 8.6 8.2 9.2 8.9 11.6 12.2 8.5 8.4 9.2 9.5 9.8 9.4
173 4.8 7.4 8.2 7.9 9.1 8.7 11.4 12.1 8.6 8.5 9.2 9.5 9.9 9.5
162 4.9 7.5 8.4 8.1 9.3 8.8 11.6 12.3 8.7 8.7 9.3 9.6 10.0 9.6
150JJ 5.0 7.6 8.3 8.1 9.3 8.9 11.6 12.4 9.0 8.9 9.5 9.9 10.2 9.9
140 5.1 7.6 8.3 8.1 9.4 8.9 11.6 12.5 9.1 9.0 9.5 9.9 10.3 ]0.0
130 5.1 7.5 8.2 8.1 9.4 8.8 11.512.3 9.1 9.0 9.4 9.9 10.3 10.0
120 5.3 7.7 8.4 8.4 9.7 9.0 11.7 12.6 9.3 9.3 9.6 10.1 10.5 10.2
110 5.5 7.9 8.6 8.6 9.9 9.1 11.9 12.8 9.6 9.5 9.7 10.2 10.7 10.4
99 1/5.7 8.0 8.8 8.9 10.1 9.3 12.1 13.1 9.8 9.7 9.9 10.4 10.9 10.6
98 !/5.0 7.2 7.9 7.8 8.8 7.7 9.5 10.2 8.5 8.6 8.8 9.1 9.5 9.3
84 lj 5.2 7.5 8.3 8.2 9.4 8.0 10.0 10.7 9.0 9.1 9.1
9.5'9.9 9.8
WATER WEEK NO.
River August September October
Mile 45 46 47 48 49 50 51 52 1 2 3 4 5
1841/9.4 6.8 7.5 9.9 7.2 7.0 6.2 1.6 0.3 0.3 1.2 0.5 0.0
173 9.5 7.0 7.6 9.9 7.3 7.0 6.2 1.8 0.5 0.4 1.2 0.4 0.0
162 9.6 7.1 7.7 10.0 7.5 7.1 6.2 1.7 0.5 0.4 1.2 0.4 0.0
1501./9.9 7.5 8.0 10.1 7.7 7.2 6.4 2.0 0.7 0.6 1.3 0.5 0.0
140 10.0 7.6 8.1 10.2 7.8 7.3 6.5 2.1 0.8 0.7 1.3 0.5 0.0
130 10.0 7.6 8.1 10.1 7.9 7.3 6.5 2.2 1.a 0.9 1.4 0.5 0.0
120 10.1 7.7 8.3 10.3 8.1 7.4 6.6 2.2 1.0 0.9 1.4 0.5 0.0
110 10.3 7.8 8.5 10.5 8.2 7.5 6.7 2.2 1.0 1.0 1.4 0.5 0.0
99 1/10.5 8.0 8.6 10.7 8.4 7.6 6.8 2.2 1.0 1.0 1.4 0.5 0.0
98 !/9.2 7.4 7.9 8.9 7.4 6.9 5.9 2.3 1.5 1.6 1.7 1.0 0.0
84 if 9.6 7.7 8.3 9.4 7.8 7.1 6.1 2.3 1.7 1.8 1.9 1.1 0.0!]
II 1/Downstream of Watana Dam Site
1/Downstream of Devil Canyon Dam Site.'2/---------~A~---4U~p~st~r~e~am of Susitna -Chulitna conflueace
!/Downstream of Susitna -Chu1itan confluence (full mixing assumed)~/At Sunshine stream gaging station at Parks Highway Bridge
SOURCE:APA 1984e
420723
840817
TABLE E.3.2.84
STREAM TEMPERATURES
WEATHER PERIOD:SUMMER 1982
NATURAL CONDITIONS
WATER WEEK NO.
River May June July
Mile 31 32 33 34 35 36 37 38 39 40 41 42 43 44
18411 5.5 4.9 7.2 7.1 8.8 9.2 8.0 9.6 11.9 10.2 10.6 10.6 9.7 10.5
173 5.2 4.6 6.8 6.7 8.5 8.9 7.9 9.5 11.7 10.2 10.7 10.7 9.7 10.6
162 5.5 4.7 6.9 6.9 8.6 9.0 8.0 9.6 11.8 10.4 10.8 10.9 9.8 10.7
1501:./5.4 4.7 6.8 6.8 8.6 9.0 8.1 9.7 11.9 10.5 11.0 11.1 10.1 10.9
140 5.4 4.7 6.8 6.7 8.5 9.0 8.1 9.7 11.9 10.6 11.1 11.2 10.1 11.0
130 5.5 4.7 6.7 6.6 8.4 8.9 8.0 9.6 11.8 10.6 11.1 11.2 10.0 11.0
120 5.9 4.9 6.9 6.8 8.6 9.1 8.2 9.9 12.0 10.9 11.3 11.5 10.2.11.2
110 6.2 5.1 7.1 7.0 8.8 9.2 8.3 10.0 12.2 11.111.5 11.7 10.4 11.4
99 J.I 6.6 5.3 7.3 7.2 9.0 9.3 8.5 10.2 12.5 11.4 11.7 12.0 10.6 11.7
98 ft.1 5.8 4.9 6.7 6.6 8.1 8.3 7.4 8.6 10.5 9.3 9.6 10.0 8.8 9.7
84 .2./6.1 5.2 7.0 6.9 8.4 8.6 7.6 9.0 11.0 9.8 10.1 10.5 9.3 10.2
WATER WEEK NO.
River August September October
Mile.45 46 ..47 48 49 50 51 52..1 2 3 4 .5
1841/10.5 10.5 10.5 9.0 7.6 6.1 6.4 4.1 2.0 0.0 0.0 0.0 0.0
173 10.6 10.6 10.6 9.1 7.6 6.2 6.3 4.1 2.1 0.0 0.0 0.0 0.0
162 10.8 10.8 10.7 ~..~.7.7 6.3 6.4 4.1 2.1 0.0 0.0 0.0 0.0
-.-.--.---.-~.-.-.--.-...----..~-.---...--.---,.......-•........._...._•...-•......_..,.__..---_........_._..._..~_._.._----.-._..._.._..._..._.-
15J)lL ._.11.•.1..11.•0._.10.9 9_.~..7 •.9 .6.5 ...6.•6.._~.3 ..2.2_.0.•2 _O.•Jl O.OJ)~.
140 11.2 11.1 11.0 9.5 8.0 6.6 6.6 4.4 2.3 0.2 0.0 0.0 0.0
130 11.2 11.0 11.0 9.5 8.0 6.7 6.6 4.4 2.3 0.3 0.0 0.0 0.0
120 11.5 11.2 11.3 9.7 8.1 6.8 6.7 4.5 2.3 0.2 0.0 0.0 0.0
110 11.7 11.4 11.5 9.9 8.3 6.9 6.7 4.5 2.3 0.2 0.0 0.0 0.0
.99.U.12.0 11.6 11.8 10.1 8.4 7.1 .6.8.4.6 2.3 0.1 0.0 0.0.0.0
98 ft./9.6 9.1 9.4 8.0 7.3 6.3 5.6 4.4 2.5 0.8 0.2 0.0 Q.O
g4 .2.1 10.1 9.7 9.9 8.5 7.6 6.6 5.8 4.5 2.6 0.8 0.0 0.0 0.0
1/Downstream of Watana Dam Site
1/Downstream of Devil Canyon Dam Site
11 Upstream of Susitna -Chulitna confluence
il Downstream of Susitna -Chulitna confluence (full mixing assumed)
II At Sunshine stream gaging station at Parks Highway Bridge
SOURCE:APA 1984e
420123
840817
l
j
j
1
I
.!
I
.~
j
I
\
I
I
I
j
\
1
.r
TABLE E.3.2.85:MAXIMUM SIMULATED RIVER STAGES
FOR CASE E-VI FLOW CONSTRAINTS,INFLOW
TEMPERATURE-MATCHING,STAGE I FLOW,
AND WINTER 1981-82 CLIMATE DATA
STAGE I
Slough or
Side Channel
Whiskers
Gash Creek
6A
8
MSII West
MSll East
Curry
Moose
8A West
8A East
9
9 u/s
4th July
9A
10 u/s
11 d/s
11
17
20
21 (A6)
21
22
River Mile
101.5
112.0
112.3
114.1
115.5
115.9
120.0
123.5
126.1
127.1
129.3
130.6
131.8
133.7
134.3
135.3
136.5
139.3
140.5
141.8
142.2
144.8
Threshold
Elevation
367
453
(Upland)
476
482
487
(Upland)
548
573
582
604
617
626
651
657
667
687
(Upland)
730
747
755
788
Simulated
Natural
Conditions
~I~
457
Simulated
Sta~e I
Conditions
[3701
@!J
459
475
f4871
EB9l
526
729
747
753
787
2.AI L river stages in feet.
Notes:
lee Front Starting Date
Maximum Ice Front Extent (River Mile)Melt':"out Date
IJ
11
L o
12-10
139
4-28
Indicates locations where maximum river stage equals or exceeds a known
slough threshold elevation.
Source:Exhibit E,Chapter 2
'l
TABLE E.3.2.86:NATURAL AND ESTIMATED MEAN MONTHLY SUSPENDED SEDIMENT }
CONCENTRATIONS AND TURBIDITY VALUES EXPECTED TO EXIT
_______________W_A_TA_N_A_RE_S_E_RV'_O-'-I_R_D_U_R_IN__G_S_T_A_G_E_I_O_P_E_RA_T_I_O_N_S l
STAGE 1 OPERATION
Month
Observed Suspended
Sediment Concentratiops~/Estimated Mean Suspended Estimated Meal
Sediment Concentrations~/Turbidity
1
j
J
1
I
]
I
t
.j
i
]
'\
(mg/1)NTU.f./
65 130
55 110
45 90
30 60
35 70
85 170
130 260
110 220
90 180
100 200
95 190
85 170N.A.
N.A.
158-1,040
N.A.
7-140
1-6
100-2,790
151-1,860
N.A.
<.1-8
23-812
65-1,110
(mg/1)
April
October
May
November
August
September
December
March
June
February
January
July
~/Data derived from Table E.2.4.23;from Exhibit E,Chapter 2 data
"""---"--"~-"
.--~/-...Turbidi:ty-estimated-byusingfactol.of +2x-)--times T:SS-concenl:;-ral;-ions
(See discussions in Exhibit E,Chapter 2).
j
j
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",'.
TABLEE.3.2.88 MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT 'SUNSHINE (CFS)
STAGE I -
WATANA (LOW)OPERATION
-;.{...•'-.":'"'--..,,-.':-;-'"':':'..!,---..
MONTH NATURAL CONDITIONS STAGE"I i7hows
'.
-fio.",.:-._..,_.•~'-:-.,;._._."F~
MAX MIN MEAN MAX MIN MEAN
OCT 20837 8176 13799 22367 11039 15942
NOV 8775 4020 6185 14272 7491 11438
DEC 6547 2675 4426 14730 7916 11705
JAN 5216 2228 3674 12066 6973 10267
FEB 4664 2095 3115 10992 6867 9386
MAR 3920 1972 2786 8548 5668 7344
APR 5528 2233 3585 7875 4905 6148
MAY 43121 10799 27674 36142 12001 20611
JUN 116152 40702 63268 81098 33618 48797
JUL 85600 45226 64143 71496 37340 54227
AUG 84940 25092 56148 82750 24281 52562
SEP 54110 14320 32867 54096 16243 33546
ANNUAL 28262 14431 23607 28439 15426 23597
.~:
j !
TABLEE.3.2.B9 ~N',l'HLY MAXIMUM,MINIMyM AND MEAN FLOWS AT SUSITNA STATION (CFS)
:STAGE I -WATANA (LOW)OPERATIONI'
MONTH NATURAL cONDITIONS
.,.
STAGE I FLOWS
OCT
NOV
DEC
JAN
FEB
HAR
APR
HAY
JUN
JUL
AUG
SEP
ANNUAL
MAX
58640
31590
14690
10120
9413
8906
13029
.88470
165900
181400
159600
109700
63159
"INI
! .
13476
8251
5"53
6365
5614
5271
4613
28~13
73838
:~~~f
37~92
38930i
MAN
32777
15063
9267
8112
7383
6412
7684
56770
112256
126590
109084
67721
46871
i
IMAX
!
I
59759
36073
23150
17556
16058
13917
15764
79365
141399
162487
155696
107286
i
63066
!
H~N
16273
13057
10806
11059
11096
9378
7259
19442
58483
86221
80080
39515
~8377
MEAN
34847
20345
16563
14707
13654
10972
10383
49672
97743
116638
105490
68491
46868
I
~I
TABLE E.3.2.89:JUVENILE CHINOOK REARING HABITAT INDEX
VALUE FOR MEAN MONTHLY DISCHARGE AT THE
SUNSHINE STATIONlI UNDER THE NATURAL
AND STAGE I OPERATING FLOW REGIMES
AGGREGATE HABITAT INDEX VALUES11
Month
Natural Flows
Side Tributary
Channels Mouths
.Stage I Flows
Side Tributary
Channels Mouths
[ I
June
July
August
0.028
0.027
0.035
0.140
0.142
0.120
0.045
0.037
0.038
0.064
0.108
0.095
September 0.040
II From Table E.3.2.88
0.055 0.04 0.055
LJ
11 Estimated from Figures E.3.2.87 and E.3.2.88
.'
TABLE E.3.2.90:SUSITNA HYDROELECTRIC PROJECT
TOPOGRAPHICAL FEATURES OF SELECTED
TRIBUTARIES OF THE PROPOSED
DEVIL CANYON IMPOUNDMENT1/,1982
Approximate Approximate
Total Length in Length
Susitna River Length Stream Drawdown Permanently
Confluence Affected Gradient Zone Inundated
Tributary (River Mile)(mO (ft/mO (mO (mO
Cheechako Creek 152.4,1.7 321 0.4 1.3
Chinook Creek 157.0 1.3 308 0.4 0.9
Devil Creek 161.4 1.5 176 0.7 0.8
Fog Creek 176.7 1.3 72 1.3 0.0
Tsusena Creek 181.3 0.4 82 0.4 0.0
1/Proposed Impoundment Elevation:1455 Ft.MSL.
Source:ADF&G 1983b
I
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,I
TABLE E.3.2.91 MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT DEVIL CANYON (CFS)
STAGE II -WATANA (LOW)-DEVIL CANYON OPERATIONS
MONTH NATURAL FLOWS
STAGE II FLOWS
MAX MIN.MEAN MAX MIN MEAN
OCT 7518 2867 5363 8638 4777 7167NOV395511462402800929317686DEC29058101703887629738424JAN22126871429824150377931FEB185868212168211.5055 7387MAR17796641086747846066245APR24056971340685839835831MAY19777342812462734843056106JUN4781414710260431095662917582JUL32388156512307524991625213542AUG3525684842065435114742319164SEP.19799 4796 12555 19799 6458 12583
ANNUAL 11254 5352 9159 11254 5613 9160
TABL'E iE ..,.......9 .....·-I !•0_)•.it..•L.
j j
!
TdTAL CHINOOK REARING HABITAT AREA[IN ALL REPRESENTATIVE GROUPS
D~RING SUMMER WEEKS UNDER
S~AGE II FLOW REGIME
______________________L~~_
i ;.I
Stage II Flows Natural Flows
----t---t-----oo ----..-------.---------------------------..----------..----I
Calendar
Week
Total iHabi tat Area ENceeded
I '~0~50%10%
"Percent of Ti me
Total Habitat Area ENceededl
90%50%10%
Percent of Time
-----------------------~---------------------------------------------------------(s~f,t)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
i !
22 5147~38 5743374 5908472 5887756 6131097 6843402!I
23 57~4908 5929310 5929310 ~,)476820 6222510 6893240
24 57557.97 5929310 5929310 3494928 6151734 6780969I!
25 5751478 5929310 5929310 5218277 6187294 6840933I [
26 57CJl4~08 5929310 5929310 5958463 6372627 6892074
27 579 4 '1°8 5929310 5929310 5960915 6245443 6836489
28 57CJl4'1 08 5929310 8634608 6963999 6108808 6790478
[
29 57~4't08 5929310 6569315 5954151 6240076 6873055
!30 5794908 6002177 e,750031 5971538 61:;':;7691 6847559
t :31 57~41'08 6085761 6784760 5517503 6294162 6815705
32 57~4908 6006532 6780969 5954772 6171091 6823350
3:2.,504-8 749 6044573 6376799 4956682 6063121 6376799
34 5080832 6091090 6219749 ~i5610::::;4 6096961 6376799! [
6474147-:rC'56Jr805:3 6186194 5517503 6138112 6292156._"\oJ
t :
36 5704::::;46 5998999 ~316496 5685t.,17.l6 61lH210258 6316496
! "37 5690164 6008042 6228691 5690184 6008042 6228691
!![38 5292~93 5960600 625954121 529219::::;596121600 6259540
39 5180~62 5839273 6216278 4987661 581119273 6216278
---------
Calendar Week 22 ==VJe~k I Beginning May 27
--'-'---~-~~::::;;...
x.
--ii....~--'~---J:..,...;
TABLE E.3.2.93:TOTAL CHINOOK REARING HABITAT AREA
IN REPRESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS UNDER
STAGE II FLOW REGIME
---------------------------------------------------------------------------------
Stage II Flows Natural Flows
-------~--------------------------------------------------------l
Calendar
Week
Total Habitat Area Exceeded
90%50%10%
Percent of Time
Total Habitat Area Exceededl
90%50%10%
Percent o·f Ti me
(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
22 4244929 4543461 4729671 3853133 4125226 4543200
23 4482101 4727844 4727544 3426713 4·124438 4449608
24 4493376 4727844 4727544 2:-$35020 4071885 4488465
25 4485923 4727844 4727544 3284299 4076823 4581977
26 4488544 4727844 4727544 3828240 4113942 4220266
27 4161529 4727844 4727544 4025392 4119204 4230208
28 4069175 4727844 4727544 3976770 4125798 4258885
29 3963805 4726794 4727544 3853137 4091048 4245477
30 ~,966421 458963~.5 4727544 3966421 41.37456 4240463
~'1 3923086 4143477 4727544 3449123 410147::::;4181791
32 4039:301 4158415 4727544 4039301 4138079 4230401
33 3190918 417~,285 4685963 3140204 4171382 4496151
:34 3197573 4176297 4634:::::42 4040200 4176297 4629213
::::;5 4037705 4348078 4725744 40~,7705 4·3~'2384 4712545
..".,4047992 4430849 4734924 -4096153 4·:,98222 4734924·_'0
:37 4165806 4528447 4728666 41512~,5 4528447 472153~.5
38 4172012 4450270 4718252 4145776 4450270 4718252
39 424492'-j 4504139 4720054 41:1.6902 4504:1.39 4720054
---------
Calendar Week 22 =Week Beginning May 27
TABLE E.3.2.94:SUMMARY O~A~CESS CONDITIONS IFOR CHUM SPAWNING SITES DURING
STAGE II qPE!RATION BASED ON ~AN,MAXIMUM AND MINIMUM AVERAGE
MO NTHLY FIlo WS
(Page 1 of 4)
I
I !I Natu"al Disc arge Stag II Dis harge
River Mille~/PassaGe IMaximum Mean Minimum Maximum Mean MinimumIi
Site Name!Des igna ~ioins Reach...)IAUG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP
I I -
Whisker's Creek 101.4~1 E:./----------
Slough ,II ---- --- ----
II
i ~Mainstem II 115.0R 1 S S S SiD U S S S S U
:11 S S S S U U S S S
S U U
I 111 --- --------!-
i IVL ----- - -- - - --
i IVR S S S U U U S S S U U U
I VR - - ---- - -----
I VIR ---- -- ---- - -I
!V11R -------- ----
i VIIIR ---- -
- -- - -- -
I
Slough 8A 126.0R I s S S S S U S S S S S U
i II S S S U U U
S S S U U U
III S S
S U U U S S S
U U U
IVL S U U U
U U S U U U U U
I IVR ---- -- ------
I VR ------- -
- ---
!VIR ------.--- -
- -
VnR ---------.:..--
I Vl11R ------------
IXR - --- ---....----
XR ---------- -
-
I
",--~-pt
TA BLE E.3•2•94 :(Page 2 of 4)
Ri ve r Mile~1
Natural Discharge Stage II Discharge
Passage Max'mum Me n Min'mum Max'mum Me,n Min'mum
Site Name Designations Reach-I·AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP
Slough 9 l28.8R I S S S S U U S S S S U U
II -- - ------ ---
III -- - -
- - - --- - -
IV ---- --- -----
V - ------- ----
Slough 9A 133.9R I S S S S U U S S S S U U
II ------------
III ------------
IV -------- ----
V ---- -
- ------
VI -- -------- - -
VII ------------
IX ------------
X ------------
Xl - -
------- ---
.Side Channel 10 133.8L I S S S U U U S S S U U U
II --- ------ ---
III ---------- - -
IV ---------- - -
V - -
- ---------
VI --- ---- ---- -
TABLE E.3.2~94:(Page 13 4)
,Natural Discharge Stage II Discharge
River iMiil~1 PassaGe Max'mum Me n Minimum Maximum Mean Min'mum
Site Name Desigriat:ions Reach-I •AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP
Slough 11 135.6R I I S S S U U U S S S U U U
II S S S U U U S S S U U U
III S U U
U U U S U U U U U
IV U U U U
U U U U.U U U U
V -- ----- - - -
--
VI - - - - -
-- -
- ---
VII ---- - -- -
--- -
Upper Side 136 I ----- ---- -
--
Channel 11 II --- - -
-- -
- ---
Slough 1 139.7R I ---- - -
-- ----
II - - - -
----_.---
III --- - - - - -
-- - -
IV ---- -
--- -
---
V -- - -
- ----- - -
139 9&VI S S S S U U S S S S U U
VII S S S U U U S S S U
U U
VIII S S
S U U U S S S U U U
IX S U
U U U U S U U U U U
i
./.-:-,.....;--
.....,.,.,
--~..~
TABLE E.3.2 •94 :(Page 4 of 4)
River Mile.!/
Natu al Disc arge Stage II Disci arge
Passa§e Maximum Mean Minimum Maximum Mean Minimum
Site Name Designations Reach-/AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP
Slough 20 l40.2R I S S S S U U S S S S S S
II S S S U U U S SiD SiD U U SiD
III --- -- -
-- --- -
IV -- - -
- --- - -
- -
V ---- - --- -
- - -
VI -- - -
- --- -
---
Side Channel 21 141.4R I S S S S S U S S S S S U
II S S S S U U S S S S U U
III -- - - - - - - ----
IV ----- --- --- -
V ----- - -
- ----
VI -- --------- -
VII ---- ---- ----
141.6R VIII --- ------ ---
IX -- -
--- -- - -
--
Slough 21 142.1R I ---- - -
------
II -- ----------
IIIL --- -
----- ---
IIIR - ----- - -
--- -
Slough 22 144.4L I S S S U U U S S S U U U
II S U SiD U U U S U U U U U
III ------- -----
a/
~/
5:./
~/
Source:EWT&A and AEIDC 1985
Source:ADF&G 19851,L=Left and R=Right,looking upstream
Influence of backwater was not evaluated since breaching flow occurs at discharge lower than those required
for providing backwater influence.
U=Unsuccessful,S/D=Successful with Difficulty,and S=Successful
TABLE E.::"'.2.95:
i
!
TOTAL CHUM SPA~NING HABITAT
IN IFG AND:DIH~B MODEL SITES
DURING SUMMER ~ONTHS
UNDER STAGE II !FLOW REGIME
------------~------------~-~-------------~------------------------------------------------,
Calendar
Week
St~g~II Flow Regime
Modelled Habitat Area Exceeded
I
90%50%10%
Pefrcent of Time
Natural Flow Regime
Modell ed Habi tat Ar-ea E>(ceeded
90%50%1121%
Percent of Time
------------~-~----------~-~-------------~-------------------------------------------------
(sq f '{:)!(sq ft)(sq ft)(sq ft)(sqft)(sq ft)
32 4669121 73342 75~31 72935 74117 76821
I
3:::;36575 73592 84506 35061 73755 78712
34 36774 73909 83557 45002 74129 84101
35 46690 75444 85:-$63 44286 76121:30 85363
36 46690 74642 86202 47448 75257 86202
37 4702Jr 76554 85~19 47448 76554 85219
38 3632:-d 74376 86928 36322 74:-'::;76 86928
39 31919 62440 86438 26285 62440 86438
-----~------~-~----------~---------------~-------~----------------------------------------
Calendar Week 32 =Week B~ginning August ~
I
----;---'--"---,--.---....--~-"---~.-~-'',~,,---'---'
TABLE E.3.2.96:TOTAL CHUM SPAWNING HABITAT AREA
IN REPRESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS UNDER
STAGE II FLOW REGIMES
-------------------------------------------------------------i-------------------------
Stage II Flow Regime Natu~91 Flow Regime
Modelled Habitat Area Exceeded Modelled,~bitat Area Exceeded
caltndar 90%50%10%90%50%10%
W.ek Percent of Time Percent of Time
(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
32 784981 835011 883332 826654 849978 883525
33 345781 837107 859996 330883 832670 858434
34 347736 8~lA605 854194 689191 836728 862500
35 784981 852626 868158 620955 852626 868158
36 78498j.838007 866908 789790 840645 866908
37 787121 840943 864098 789790 840943 864098
38 729972 844361 867598 729972 844361 867598
39 698246 825264 86560~::'608728 825264 86560~5
Cal.ndar Week 32 =Week Beginning August 5
I
i
I !!
TABLE E.3.2~97:TOTAL CHUM SPAWNING HABITAT
1 I AVAILABLE !FOR INCUBATION OF EMBRYOS
i IN IFG AND DIHAB MODEL SITES
.UNDER STAGE II FLOW REGIME__________________________J __~J _
Stade iII Flow Regime I Natural Flow Regime
ModelledlH~bitat Area Exceeded Modelled Habitat Ar~a Exceeded
Calendar 90~I 50~10~90~50~10~
Week Pe~ce,nt of Time I Percent of Time
";......Ii.I·.-,.-,
----------~---~-----------~-~----------------~--------------------------------------------
(sq ft)(tsq ft)(sqft)(sq ft)(sq ft)(sq ft).
40 34169 !44783 80392 21116 44783 80392
41 36561 I 41813 49157 19923 38552 49157
42 38974 i 41503 45591 15404 21348 42731
43 40441 !42502 44374 11066 20021 29479
44 41885 !43572 45466 8127 16393 21148
45 43967 i 45240 46727 7586 13242 19511
46 44015 i 46768 47122 7112 12294 16391
47 46005 f 47016 47473 6230 11547 1517.2
48 46984 !47383 47838 5552 10872 14053
----------~~--------------+------------------~--------------------------------------------
Calendar Week 40 =Week Beginning October 1
---<,..__._<~'---
\..:-----
TABLE E.3.2.98:TOTAL CHUM SPAWNING HABITAT
IN REPRESENTATIVE GROUPS 2~3,AND 4
AVAILABLE FOR INCUBATION OF EMBRYOS
DURING EARLY WINTER WEEKS UNDER
STAGE II FLOW REGIMES
Calefndar
Wd-ek
Stage II Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Percent of Time
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Percent of Time
(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
40 714456 776940 855079 743236 790083 887478
41 731688 764420 797989 761361 790087 830175
42 749076 763112 780348 726475 794180 813151
43 758633 767324 775218 709737 801152 813434
44 764721 771836 779820 731494 776597 819621
45 773498 778866 785214 752897 775962 829240
46 773704 785478 787726 774723 791514 841854
47 782092 787049 789953 7928:::',0 804263 85:::',051
48 786847 789381 792271 805815 816042 -829623
Cal.ndar Week 40 =Week Beginning October 1
TABLE E.3.2.99:SIMULATED STREAM TEMPERATURES
WEATHER PERIOD:SUMMER 1981
CASE E-VI FLOW CONSTRAINTS
STAGE II FLOW REGIME
RIVER MAY JUNE JULY
MILE 31 32 33 34 35 36 37 38 39 40 41 42 43 44
150 2.4 3.0 3.9 4.4 4.9 6.0 5.6 4.8 6.5 8.4 7.7 5.9 5.1 9.1
140 2.7 3.4 4.3 4.8 5.4 6.3 6.1 5.4 6.9 8.7 8.1 6.3 5.4 9.3
130 3.0 3.9 4.7 5.3 6.0 6.4 6.6 6.1 7.2 8.6 7.7 6.6 5.7 9.3
120 3.3 4.5 5.3 5.9 6.7 6.8 7.2 6.8 7.7 9.0 8.2 7.0 6.0 9.6
110 3.6 5.0 5.9 6.4 7.4 7.2 7.8 7.5 8.1 9.4 8.7 7.4 6.3 9.8
99 3.9 5.5 6.4 7.0 8.1 7.5 8.4 8.2 8.6 9.7 9.1 7.8 6.7 10.0
98 4.0 5.5 6.2 6.5 7.3 6.6 7.7 8.0 7.7 8.2 7.8.7.7 6.2 8.9
84 4.4 6.3 7.1 7.3 8.3 7.2 8.6 9.0 8.5 8.8 8.4 8.5 8.2 9.5
RIVER AUGUST SEPTEMBER
MILE 45 46 47 48 49 50 51 52 1 2 3 4 5
150 9.9 9.5 8.7 9.0 9.7 9.7 9.6 9.0 8.3 7.8 7.3 6.7 5.9
140 10.0 9.5 8.8 9.2 9.7 9.7 9.6 8.8 7.9 7.5 7.0 6.4 5.3
130 10.0 9.4 8.8 9.2 9.7 9.5 9.4 8.3 7.3 7.0 6.5 5.9 4.6
120 10.2 9.5 9.0 9.4 9.8 9.5 9.3 8.0 6.9 6.7 6.2 5.5 4.0
110 10.4 9.5 9.1 9.6 9.9 9.5 9.3 7.8 6.6 6.5 5.9 5.3 3.4
99 10.6 9.6 9.3 9.8 10.0 9.5 9.3 7.5 6.2 6.1 5.6 4.9 2.7
-98--9-.2---8.Z 8.-3-8-.6---8.2 -7·.9~-7 •..s-.5 .3--4·"Si·4-.6-4.3-:3.6 1.9·
84 9.6 8.3 8.6 9.1 8.4 7.9 7.2 4.7 4.0 4.1 3.8 3.1 1.1
'}
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1
)
1
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J
1
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T
TABLE E.3.2.100:SIMULATED STREAM TEMPERATURES
WEATHER PERIOD:SUMMER 1982
CASE E-VI FLOW CONSTRAINTS
STAGE II FLOW REGIME
RIVER MAY JUNE JULY
MILE 31 32 33 34 35 36 37 38 39 40 41 42 43 44
150 3.1 3.2 3.5 3.9 4.1 4.3 4.9 6.4 7.9 5.7 5.1 7.3 8.3 6.9
140 3.3 3.4 3.8 4.1 4.5 4.7 5.2 6.7 8.4 6.3 5.6 7.8 8.5 7.1
130 3.7 3.6 4.1"4.4 4.9 5.0 5.4 7.0 8.6 6.8 6.2 8.1 8.5 7.4
120 4.1 3.9 4.6 4.9 5.5 5.5 5.8 7.5 9.2 7.4 6.8 8.7 8.9 7.8
110 4.4 4.2 5.0 5.3 6.0 5.9 6.2 8.0 9.8 7.9 7.4 9.2 9.2 8.1
99 4.8 4.5 5.4 5.7 6.5 6.4 6.5 8.5 10.4 8.6 8.1 9.8 9.6 8.5
I 98 4.7 4.4 5.3 5.5 6.3 6.5 6.1 6.8 8.7 7.8 7.6 8.4 7.9 8.2
84 5.2 4.8 6.0 6.1 7.2 7.6 6.7 7.8 9.8 8.7 8.6 9.4 8.7 9.1
>'
RIVER AUGUST SEPTEMBER
MILE 45 46 47 48 49 50 51 52
150 8.2 8.8 9.7 9.1 9.8 9.5 9.9 9.9
140 8.5 9.0 9.9 9.2 9.8 9.5 9.8 9.7
130 8.7 9.1 10.0 9.3 9.6 9.3 9.6 9.3
120 9.1 9.4 10.3 9.5 9.7 9.4 9.6 9.2
110 9.5 9.7 10.6 9.7 9.8 9.4 9.6 9.1
99 9.9 10.0 10.9 9.9 9.8 9.5 9.5 8.9
98 8.6 8.4 9.0 7.8 8.0 7.5 6.8 6.5
84 9.4 9.1 9.6 8.4 8.1 7.5 6.7 6.0
2.All river stages in feet.
Source:Exhibit E Chapter 2
}
,-J'
II
\
,I
l
I
I
1
1
1
)
j
1
}
)
)
-J
12-29
1333....26
746
752
785
1981-1982
Winter
f3701
f459l
461
476
487
490
521
Simulated
Stage 11
Conditions
Simulated
Natural
Conditions
1981-1982
Winter
1:::1
457
472
1484 1
486
523
1549 1
571
583
606
620
Threshold
ElevationRiverMile
Indicates locations where maximum river stage equals or
exceeds a known slough threshold elevation.
TABLE E.3.2.101:SUSITNA HYDROELECTRIC PROJECT
MAXIMUM SIMULATED RIVER STAGES
FLOW CASE E-VI,INFLOW-MATCHING
STAGE 11 FLOW REGIME
Slough or
Side Channel
tR.'X-3 Ice Front:Starting Date
Maximum Ice Front Extent (River Mile)
Melt-out Date
NOTES:
1.0
Whiskers 101.5 367
Gash Creek 112.0 453
6A 112.3 (Upland)
8 114.1 476
MS11 West 115.5 482
MS11 East 115.9 487
Curry 120.0 (Upland)
Moose 123.5 548
8A West 126.1 573
8A East 127.1 582
9 129.3 604
.9_ul s .J~Q.{)...617
4th July 131.8 626
9A 133.7 651
10 u/s 134.3 657
11 dl s 135.3 667
11 136.5 687
..__..•_----,._._•..__._---,.._--_.......,._..~--..._-T7···-139;3····(Uptand-)
20 140.5
21 (A6)141.8 747
21 142.2 755
22 144.8 788
TABLE E.3.2.102:NATURAL AND ESTIMATED MEAN MONTHLY
SUSPENDED SEDIMENT CONCENTRATIONS
AND TURBIDITY VALUES EXPECTED TO
EXIT DEVIL CANYON RESERVOIR DURING
STAGE II OPERATION
Month
January
February
.March
April
May
June
July
August
September
October
November
December
Stage II Operation
Suspended Estimated Mean
Sediment Suspended Estimated
Concentra-Sediment Mean
tionsl1 Concentrationsll Turbidity
(TJ,lg/1)(mg/1 )NTU.~/
(1-8 60 120
N.A.45 90
1-6 40 80
N.A.30 60
65-1,110 30 60
151-1,860 55 110
100-2,790 110 220
158-1,040 110 220
23-812 90 180
7-140 80 160
N.A.80 160
N.A.75 150
N.A.=Not Available
II Data derived Table E.2.4.49 (in Exhibit E,Chapter 2)
Zl Turbidity estimated by using factor of (2x)times TSS
concentrations (see discussions in Exhibit E,Chapter 2).
'J
(CFS)
STAGE II DISCHARGE
MA~MIN(.MEANMEANMAXMIN
TABLE E.3.2.103j MQNTHLY MAXIMUM,MINlMUM AND MEAN FLOWS AT SUNSHINE
I :
i 1SrA~E II -WATANA (LQW)-DEVIL CANYON OPERATIONS
I .
NATURAL OISFHARGEMONTH
OCT
NOV
DEC
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
20837
8775
6547
5216
4664
3920
5528
43121
116152
85600
84940
54110
8176
4020
2675
2228
2095
1972
2233
10799
40702
45226
25092
143~0
13799
6185
4426
3674
3115
2786
3585
27674
63268
64143
56148 .
32867
21708
13641
125~8
113~2
109ti8
9593
10018
37836
78540
74011
830~0
54110
11320
5805
5025
6697
6606
6278
6161
12811
33014
37295
24031
1598.3
15636
11533
11156
10173
9285
7946
6062
21360
44676
'54654
54607
32676
ANNUAL 28262 144~1 23607 28396 15886 23609
'-----
ANNUAL 63159 38030 46871 63155 38030 46879
J
TABLE E.3.2.105:FEATURES OF SELECTED TRIBUTARIES WITHIN
THE STAGE III WATANA IMPOUNDMENT1/)
Approximate Approximate
Susitna Additional Total Length in Length
JRiverLengthLengthStreamDrawdownPermanently
Tributary Confluence Affected Affected Gradient Zone Inundated
(River Mile)(mi)(mO (ft/mO (mO (mi)
I
Deadman Creek 186.7 0.7 2.7 253 .5 2.2
Watana Creek 194.1 1.0 8.51:./601:./0.0 8.5 IEastForkN/A 1.2 1.21/1131/1.1 0.1
West Fork N/A 2.1 2.111 671/L8 0.3
JKosinaCre~k 206.8 1.7 4.5 118 1.0 3.5
Jay Creek 208.5 1.4 3.5 143 .8 2.7
Goose Creek 231.3 1.2 1.2 114 1.1 0.1
Oshetna River 233.4 2.2 2.2 41 2.2 0.0
1/Stage III Watana.Water Surface Elevation:2,185 ft.MSL
Z/Watana Creek below forks
---J,:F .Wal:an-aCree1<.above :r.~=t=-~--~-~·~··_-~~
Source:Adapted from ADF&G 1983b
I
j
I
\
·1
)
]
I
r
TABLE E.3.2.106:Monthly Maximum,Minimum and Mean Flows at Gold Creek (CFS)
Stage III -Watana (High)-Devil Canyon Operations
Month Natural Flows
With-Project Conditions
Early Stage III Flows Late Stage III Flows
Max Min Mean Max Min Mean Max Min Mean
Octob r 8,212 3,124 5,825 9,488 5,032 7,720 11,090 5,032 8,609
Novem er 4,192 1,215 2,578 8,724 5,235 8,244 11 ,466 3,000 9,530
Decem er 3,264 866 1,828 9,401 8,074 9,011 12,857 5,466 10,987
Janua y 2,452 724 1,524 8,471 7,456 8,256 11,752 6,547 10,268
Febru ry 2,028 723 1,309 8,284 7,358 8,112 11,611 6,459 10,139
March 1,900 713 1,173 7,462 6,575 7,280 10,533 5,772 9,076
April 2,650 745 1,441 7,187 5,610 6,623 9,874 4,923 8,064
May 21,890 3,745 13 ,483 10,524 6,080 7,643 12,857 5,912 9,027
June 50,580 15,500 27,795 10,394 7,867 9,223 12,388 7,907 10,355
July 34,400 16,100 24,390 26,016 8,000 13,156 11,748 8,000 9,414
Augus 37,870 8,879 21,911 36,698 8,000 18,489 22,316 8,000 10,710
Septe ber 21,240 5,093 13 ,493 20,605 6,767 13,406 18,391 6,767 10,761
ANNUAl 11,961 5,596 9,781 11,961 6,942 9,781 11,961 6,333 9,742
1 'TABUE E.3.2.107:,
,
ITQTAL CHINOOK REARING HABITAT AREA
I~ALL REPRESENTATIVE GROUPS
DWRING SUMMER WEEKS UNDER
EARLY STAGE III FLOW REGIME
--------~-~----------~-+---~---------+------~------------------------------------
¢arly stage III Flows Natural Flows
---~-~-------------+-------------------------------------------;illTotaliHabitatAreaExceeded I Total Habitat Area Exceeded I
Calendar I 90%501.i 101.I 901.501.101.
Week I 1 I Percent oflTime I Percent of Time
--------~~~L~------~~4-~-----~-----~~+---------~-~------~------------------------
?,:,>!.....L'
23i
241
251
26:
27
28
291
30'
31
32
:33
34
::~5i
361
37'
38
39i
(sq ft)
,I
I I
I !5346615
5738188
I I
5711 1 964
5729148
5782783
I !5865743
5794908I I5794908I I5767194, I
5794908
I I5794908, i
57947'°8
551-2 +°1
5725102
I I5704346,I
5378032
51471.38
!i51t7~38
(SA ft)
5805357
5929310
5929310
5929310
5929310
5929310
5929310
5929~:;10
5929310
5985561
6006532
5996771
6006819
6078320
6000258
6008042
5960600
5799111
<sq ft)
5928598
5929310
5929310
5929310
:D929310
5929310
6089966
'6506449
6750031
6784760
!
6595469
I
~376799
6216433
6291106
I{:>307107
6228691
6259540
6216278
(sq ft)
5887756
5476820
3494928
5218277
5958463
5960915
6963999
5954151
5971538
5517503
5954772
4956682
5561vn4
5517503
5685606
5690184
5292193
4987661
(sq ft)
6131097
6222510
6151734
6187294
6372627
6245443
611218808
6240076
6137691
6294162
6171091
6063121
6096961
6138112
6000258
6008042
5960600
5809273
(sq ft)
684341212
6893240
6780969
68409~:;3
6892074
6836489
6790478
6873055
6847559
6815705
6823350
6376799
6376799
6292156
6316496
6228691
6259540
6216278
~-:
Calendar,Week 22 =We~kIBe~inn~ng Mayl27
~--'---------'
TABLE E.3.2.108:TOTAL CHINOOK REARING HABITAT AREA
IN ALL REPRESENTATIVE GROUPS
DURING SUMMER WEEKS UNDER
LATE STAGE III FLOW REGIME
Late Stage III Flows Natural Flows
I,------------------------------------------------------------------1
Calendar
Week
Total Habitat Area Exceeded
90%501.10%
Percent of Time
Total Habitat Area Exceeded:
901.501.101.
Percent of Time
(sq ft)(sq ft)(sq ft)(sq ·ft)(sq ft)(sq ft)
22 5586825 5735399 6194400 5887756 6131097 6843402
23 5666345 5807735 5929310 5476820 6222510 6893240
24 5673545 5808222 6190181 3494928 6151734 6780969
25 5671184 5847999 6152700 5218277 6187294 6840933
26 5663766 5794908 5929310 5958463 6372627 6892074
27 5716871 5909072 5929310 5960915 6245"-143 6836489
28 5726084 5902044 5929310 6963999 6108808 6790478
29 5694015 5929:::510 5929310 5954151 6240076 6873055
30 5704532 5926367 5929:::::10 5971538 6137691 6847559
31 5664157 5893721 5929310 5517503 6294162 6815705
32 ~)693549 5842494 5929:::',10 5954772 6171091 t1823350
::~3 5710287 5929310 6146531 4956682 6063121 6376799
34 5757441 5929310 6126918 55610:::::4 6096961 6376799
35 5739023 5929310 6197795 5517503 6138112 6292156
36 5681436 5794908 621643:::;5685£')06 6000258 6316496
37 5378032 5735891 6206042 5690184 6008042 6228691
38 5 j.LJ.7 1 ::::;s 5754687 6163950 5292193 5961(~61Zl0 6259540
39 5147138 5796548 5983301 4'-=jl87661 5809273 6216278
---------
Calendar Week 22 =Week Beginning May 27
I
I,
I I
Iij
TABLE E.3.2.109:
I i
I I
: I
I
WOTAL CHINOOK REARING HABITAT AREA
IN REPRESENTATIVE GROUPS 2,3,AND 4
pURING SUMMER WEEKS UNDER
EARLY STAGE III FLOW REGIMES
--------------------l-r-------------~--------------------------------------.------
i I Early Stage IiII Flows I Natural Flows I
-~r-~------~------~--------------------·------------------------1
Toltall Habi tat Areal E>:ceeded I Total Habitat Area Exceeded I
Cal endC}r I!9;0%50%,10%I 90%50%10%
l.tJeek i I I I Percent 9f Ti me I Percent of Time
------..,;.---~--------~-~-I---'-----------I--.;..--------------------------------------.--.----,I(isq:f t ) (sq f t ) (sq f t )(sq f t ) (sq f t ) (sq f t )
I
+2 4~..,..18476 160121147 4730723 3853133 4125226 4543200.....:-~_..
':)7 414~8344 4727844 4727844 3426713 4124438 4449608L-.:J
24 414113518 4727844 4727844 2335QJ~20 4071885 4488465
25 ~451764 4727844 4727844 3284299 4076823 4581977
26 I i 4727844 4727844 3828240 4113942 42202664;629940
27 4:725744 4727844 4727844 4025392 4:L 19204 4230208
28 ~145386 4727844 4727844 3976770 4125798 4258885
29 410~8774 4727844 4727844 3853137 4091048 4245477
30 4i0~8592 4725744 4727844 3966421 4137456 4240463
31 4;O02079 4171971 4727844 ~~~449123 4101473 4181791
32 41040695 4179058 4727844 4039301 4138079 4230401
::J3 4040399 4186821 4727844 3140204 4171382 4496151
34-"'!46'"'8""8 4252662 4727844 4040200 4176297 4629213...:...::.._..
I I
3'5 48 1'9665 4433162 4727844 4037705 4332384 4712545
36 4i0:::~7663 4430849 47:::'~4924 409615:::'~4398222 47:::'~4924
37 4195806 4448220 472153~5 4151235 4528447 4721533
38 4172012 4357829 4718252 4145776 4450270 4718252II39424492944924904720054411690245041394720054
---------!I
Calendar Week 22 =We$k Beginning M.y 27
!
I
----..:'~-',-L --.'---'
TABLE E.3.2.11121:TOTAL CHINOOK REARING HABITAT AREA
IN REPRESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS UNDER
LATE STAGE III FLOW REGIMES
Late Stage III Flows Natural Flows
Calendar
Week
:------------------------------------------------------------------1
Total Habitat Area Exceeded I Total Habitat Area Exceeded I
90%50%10%I 90%50%10%
Percent of Time I Percent of Time
(sq oft)(sq ft)(sq ft)(sq ft)(sq f°t)(sq ft)
22 4321512 4427439 471215611 3853133 4125226 454320121
23 4331791 4518613 4729067 3426713 4124438 4449608
24 4347859 4603977 4727844 2335020 4071885 4488465
25 4335317 4655812 4727844 3284299 412176823 4581977
26 432121770 4464864 4727844 3828240 4113942 4220266
27 4432822 4725744 4727844 4025392 4119204 423121208
28 4446286 4725744 4727844 ~597677l?l 4125798 4258885
29 4399419 4727844 4727844 :::'~853137 409112148 4245477
30 4~~:;8121656 4727316 4727844 :::'~966421 4137456 4240463
:::'\1 432612196 4712075 4727844 3449123 4101473 4181791
32 4398738 4711701 4727844 4039:::::01 413812179 423121401
33 4120335 4691978 4727844 3:1.40204 4171382 4496:1.51
34 412181098 4675669 4727844 4040200 4176297 4629213
":'"c"4168675 4675177 4727844 4037705 4332384 4712545"_'w
7"./4145789 4623713 4727844-4096153 439822:;~4734924"_'0
37 428711211 4421124 4657908 4151235 4528447 4721533
38 4244929 ·4463560 473147:::;4145776 4450270 47:L8252
39 4244929 456:1.480 4728717 4116902 4504139 4720054
---------
Calendar Week 22 =Week Beginning May 27
TABLE E.3.2 •111 :SUMMARY OF,ACCESS CONDITIO~S FOR CHUM SPAWNING SITES DURING (Page 1 of 4)
STAGE I OPERATION BASED ON MEAN,MAXIMUM AND MINIMUM AVERAGE
MONTHLY FLOWS
-
!I,
-.-I !I Early Flows FlowsIINau:ral Fl ws tage II Late tage II
River Mile~1 PassagE Max "mum Jiteari Min"mum Maximum Me n Min"mum Max"mum Mean Minimum
:Site Name Designations II I AUG SEP AWG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEP AUG SEPR~ach -
i !
Whisker's Creek 101.41 !I 5::.1 I-T ----- --- - - - - ---
Slough in ----- - - ------- -
--I 'T!~I IMainstemII115.0R !I ,S S S siD U S S
S S S U U S S S S U
[II IS S S
S U U S S S S S U U S S U U U
III --I --- - -
-- --------
IVL - -
T - - ---------- -
--TIVRSSS U U U S S U U U ·U U S U U U U
IVR --1 - - - ----- --- ----
VIR --1 -- -
- - -
-- -------
i 1VIIR- - -
--- -
;..----- - ---
VrtIR --I - -
----- --------T
Slough 8A 126.0R I S S S S S U S S S S S U S S S S S U
:II S S S U U U S S S U U U S S U U U U
ill I SiD siD USSSU U
U S S U U U S U U U
t VL S U U U U U S U U U U U U
U U U U U
!IVR -------- ---- -----
VR - -
1 ----- ----- -----
VIR - -
1.--- ------------
I .,
VIIR --,---------- -----
niIR --I ---- --- -
-------
IXR - -T ---- -------- -
--
iXR --T -------------- -
:
,--------------'------..J '-------''-;---'~L~:'------'
- ----_.-._-.~_.----.~-
--..~---~--------"--"--'------'-_..---_.-----.--~..._-
TABLE E.3.2.111:(Page 2 of 4)
Nat ral Flow Early Stage II Flows Late tage III Flows
River Mil~1 Passage M x Mean MOn Max Me,n Min M x
Me,n MOn
Site Name Designations Reach-I Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep
Slough 9 128.8R I S S S S U U S S S S U U S S U U U U
II ------- -----------
III -- - ----- ------- - -
-
IV -- - ------- - -- -
- - --
V - -
-- - - - - -
----- - ---
Slough 9.ll 133.9R I S S S S U U S S S S U U S S U U U U
II - ----- -- - - - - -
--- --
III -- -
--------- ------
IV -- -
--- -- -
--- ----- -
V --- - - - - -
- - - -
--- - -
-
VI -- -
--- - - - - - - -
-----
VII - -
------- - ----- ---
VIII -- --- --- -- -
-- - -
---
IX - - ---- -
----- ---- -
-
X - -
------ - -
-- - -
- ---
XI ---- - -
-- -
----- --- -
Side Chat nel 10 133.8L I S S S S U U S S S U U
U S SiD U U
U U
II -- - -- -- -
- ----- ----
III - - -
-------- - - -
--- -
IV --- ---------------
V ------------------
VI -- -
-------------- -
TABLE E.3•2 .111 :(Page 3 of 4)
1
Natural Flo,w Early tage III Flows Late tage III Flows
River Mile~1 Passa§e Max Mean!Min Max Mean Min Max Mean Min
Site Name Designations Reach~1 Aug Sep Aug S~p Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep
Slough 11 135.6R I!S S S U U U S S S U U U S S U U U U
II!S S S di U U S S SiD U U U S SID U U U U
III!S U U l1r U U S U U U U U U U U U U UII'IV;U U U U U U U U U U U U U U U U U U
V;I --- -
-i --- ---- - ---- -I
VIi - -
--,----- - - -
------
VIIi -- -
-!--- - - -
---- - ---
:II
Upper Side 136.3R I!----!- - -
---- -- --- --
Channel 11 i II:--I -- - - - - - - -
--- -
-- -
Slough 19 139.7R Ii ----I --------------
II --'--'-- -
-- ------ - - -
III - ---;-- - ----- -
-- - - -
I~- --_!--------------
Vi - --_!--- - ---- - - - -
--
139.9R VIr S S S 81 U U S S S S U U S S U U U U
VIIi S S S ~U U S S S U U U S S U U U U
VIII!s s S U!U U S S SID U U U S SID U U U U
IX!S U U U!U U S U U U U U U U U U U U
Slough 20 140.2R I S S S si U U S S S S U U S S U U U'U
II!S S S Uj U U S SiD U U U U S U U U U U
III!- ---I ----- - ---- -
---,
IV;----'--- -
--- - - -
-- -
-
Vi -- -
-j -- -
..;.- - - -- -
- - - -
VI!- --i ---------- -----
r.,!
~~,'-----..',I!":,i','...."---~
~---~--'----~------_._~~-----_.-
,-~--~---~...----,'-~,-~,-',--,--
TABLE E.3.2.111 :(Page 4 of 4)
Na ural Flo s Early tage III Flows Late tage III Flows
River Mi1e~/Passage Max Mean Min Max Mean Min Max Mean Min
Site Name Designations Reach-/Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep Aug Sep
Side ChaI1 nel 21 141.4R I S S S S S U S S S S S U S S S S S U
II S S S S U U S S S S U U S S S S U U
III ------------ - -
- ---
IV -- --- --- -
--- ----- -
V ----- ---- ---------
VI ------ - --- - - -
--- - -
VII ----- - -
- -- -
-- -
--- -
141.6R VIII ----------- -
------
IX ------- -
- -- -
--- -
--
Slough 21 142.1R I - -
--- -
- --- -
--- - ---
II - -
----- -
------- -- -
llIL - -
- -- -
---- --------
IIIR ------- - -
--- -
-----
Slough 22 144.4L I S S S U U U S S S U U U S S U U U U
II S U SiD U U U S U U U U U SiD U U
U U U
III ---------- -
- ------
~/Sourc e:EWT&A and AEIDC 1985
E./Sourc e:ADF&G 19851,L=Left and R=Right looking upstream
E./Influe nce of backwater was not evaluated since breaching/flow occurs
!!/
at dis charg~lower than those required for providing backwater influence.
U=Uns ccessfu1 conditions
S/D=Su ccessful with difficulty
S=Succ essful conditions
I
TABLEE.3.2~112:TPT~L CHUM SPAWNING H~BITAT
IN IFG AND DIHAB MODEll SITES
D~RING SUMMER MONTHS [
UNDER STAGE III FLOW REGIME
-------------------------------------~-~-----------------+------------------------------------------------------_._-------------
Natural Flow Regime
Modelled Habitat Area E>:ceeded
9111%5111%1 0'l.
Percent of Time
Calendar
Week
Early Stage III Flo~Regime I La~e St.age III Flow Regime
Modelled Habitat ArearE>:ceeded I Modelled Habitat Area E>lceeded
9111%50%'1111%I 9111%5111%1111%
Percent of Time i I !Percent of Time!;:;!:;1
-------------------------------------~--------------~----~---------------------------------~-------------_.------~_._---~-------
(sq ft)(sq ft)ft.)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)
32 46690 73195 75531 47387 48725 67764 72935 74117 76821
33 4669111 7331112 83706 4669111 4941113 73881 3511161 73755 78712
34 44695 73369 83557 46690 48963 73269 451111112 74129 8411211
35 4669111 75444 85363 .';1-669111 50633 74183 44286 7611130 85363
36 46690 74642 85831 46690 5441115 83557 47448 75257 8621112
37 411111112 76554 85219 411111112 59032 84199 47448 76554 85219
38 3111653 74376 86928 30653 5911147 86787 36322 74376 86928
39 30653 55189 86150 ::;:;111653 53196 84911 26285 6244111 86438
-------------------------------------~-------------------t--------------------------------------------------------------------
Calendar Week 32 =Week Beginning Aug~st 5
:'~'---'.~,-------,
TABLE E.3.2.113J TOTAL CHUM SPAWNING HABITAT AREA
IN REPRESENTATIVE GROUPS 2,3,AND 4
DURING SUMMER WEEKS UNDER
STAGE III FLOW REGIMES
Calendar-
Week
Early stage III Flow Regime
Modelled Habitat Area EHceeded
90%50%10%
Percent of Time
Late Stage III Fl~w Regime
Modelled Habitat Ar-ea Exceeded
90%50%10%
Percent of Time
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10%
Percent of Time
32
33
34
35
36
37
38
39
(sqft>(sq ft>(sq ft)(sq ft)(sq ft)(sq ft)(sq ft>(sq ft)(sq ft)
784981 832073 883256 789403 796449 845897 826654 849978 883525
784981 829384 863293 784981 798869 853837 330883 832670 858434
470522 833106 854194 784981 797299 847750 689191 836728 862500
676094 843238 867223 784981 803249 851937 620955 852626 868158
784981 840645 866908 784981 816694 866252 789790 840645 866908
757205 834550 864098 757205 825269 864435 789790 840943 864098
689123 844361 867598 689123 827055 867598 729972 844361 867598
689123 819486 865277 689123 812382 865277 61218728 825264 86561213
Calendar We~k 32 =Week Beginning August 5
TABLE E.3.2.114;TOTAL CHUM SPAWNING HABITAT
A~AI~ABLE FOR INCUBATION OF EMBRYOS
IN IFG AND DIHAB MODELl SITES
UNDER STAGE III FLOW R~GIME'
--------------------~-----------------.;---:------------------~-----------------------------~-------------------------_._-.---------
Calendar
Week
.,.
Ea~ly Stage III Flow Regime
Modell ed Habi tat Are!a E>lceeded
90/.50/.'10/.
Percent of Time
Late Stage III Flow Regime
Modelled Habitat Area Exceeded
90/.50/.10/.
Percent of Time
Natural Flow Regime
Modelled Habitat Area Exceeded
90/.50/.10/.
Percent of Time
---------------------~--~------------~--~-----------------~-------------------------------------------------------------------
(sq ft)(sq ft)~sq ft)(sqi ft)(sq ft)(sq ft)
40 .30653 44783 80392 30653 49998 57390 21116 44783 80392
41 !30653 43183 49157 3~653.49470 66367 19923 38552 49157
42 !25428 43379 46716 21554 48306 64789 15404 21348 42731
43 142049 44413 46587 18965 49023 66165 11066 20021 29479
44 143406 45358 4~879 14224 51492 57035 8127 16393 21148
45 1 45404 46736 47170 16455 55403 63008 7586 13242 19511
46 146833 47134 i 47512 4b704 61729 71412 7112 12294 16391
47 i 47280 47543 i 47891 417222 71218 86277 6230 11547 15172
48 147708 47949 I 48556 4 17714 79618 87196 5552 10872 14053
~~~:~~~;-~::~-~;-:-~::~-;:;~~~~~;-~;;9i~:~-~---------------~-------------------------------------------------------------------
.,I
.~'---''~'---
TABLE E.3.2.115:TOTAL CHUM SPAWNING HABITAT
IN REPRESENTATIVE GROUPS 2,3,AND 4
AVAILABLE FOR INCUBATION OF EMBRYOS
DURING EARLY WINTER WEEKS UNDER
STAGE III FLOW REGIMES
Calendar
Week
Early Stage III Flow Regime
Modelled Habitat Area Exceeded
90/.50%10%
Percent of Time
Late Stage III Flow Regime
Modelled Habjtat Area Exceeded
90%50/.10%
Percent of Time
Natural Flow Regime
Modelled Habitat Area Exceeded
90%50%10r.
Percent of Time
40
41
42
43
44
45
46
47
48
(sq ·ft)(sq ft>(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft)(sq ft>
689123 776940 855079 689123 800986 827328 743236 790083 887478
689123 770193 797989 689123 799108 843478 761361 790087 830175
592951 771022 785145 521634 793526 840746 726475 794180 813151
765413 77538121 784545 481271 797514 843128 709737 801152 813434
771135 779363 786182 360953 806313 826064 731494 776597 819621
779559 785275 788026 417575 820249 837661 752897 775962 82924111
785889 787798 790199 785068 835446 852213 774723 791::;14 841854
788729 790399 792607 788357 851878 869312 792830 804263 853051
791446 792973 795849 791484 865771 867986 805815 816042 829623
Calendar Wkek 40 =Week Beginning October 1
}
TABLE E.3.2.116:SUSlTNA HYDROELECTRIC PROJECT 1
SIMULATED STREAM TEMPERATURES
STAGE III
(WEATHER PERIOD:SUMMER 1981
CASE E-VI FLOW REQUIREMENTS
STAGED CONSTRUCTION
50 FT DRAWDOWN AT DEVIL CANYON
2 LEVELS OF PORTS
RIVER MAY JUNE JULY I
MILE 31 32 33 34 35 36 37 38 39 40 41 42 43 44
15ol.1 j
2.7 3.2 4.0 4.5 5.2 6.2 7.3 8.5 8.2 7.3 7.0 8.5 9.8 10.4
140 2.9 3.5 4.3 4.8 5.6 6.4 7.6 8.8 8.5 7.6 7.4 8.8 10.0 10.6 I1303.1 3.9 4.7 5.2 6.1 6.6 7.9 9.1 8.5 7.8 7.4 8.6 9.7 10.1
120 3.4 4.4 5.2 5.7 6.7 7.0 8.5 9.7 8.9 8.2 7.8 9.0 10.1 10.5
110 3.6 4.8 5.7 6.2 7.3 7.3 9.0 10.2 9.3 8.6 8.2 9.3 10.5 10.8
992:.1 3.9 5.3 6.1 6.7 7.8 7.6 9.5 10.7 9.6 9.0 8.6 9.7 10.8 11.1 .j9adl4.0 5.4 6.1 6.4 7.3 6.7 8.0 8.7 8.0 8.0 7.8 8.1 8.6 8.6
84!±1 4.4 6.2 7.0 7.2 8.3 7.2 8~8 9.5 8.7 8.7 8.4 8.8 9.2 9.3
-"1
RIVER AUGUST SEPTEMBER !MILE 45 46 47 48 49 50 51 52 1 2 3 4 5
15011 9.9 5.3 5.0 6.6 7.3 7.3 7.6 8.1 7.5 7.0 6.6 6.1 5.4 ]140 10.1 5.6 5.2 6.8 7.4 7.4 7.6 7.9 7.3 6.9 6.4 5.9 5.0
130 9.8 5.7 5.4 7.0 7.5 7.4 7.6 7.5 6.9 6.6 6.1 5.5 4.5
120 10.1 5.9 5.7 7.3 7.7 7.5 7.6 7.3 6.6 6.4 5.9.5.2 3.9
J11010.4 6.1 5.9 7.6 7.9 7.6 7.7 7.1 6.4 6.2 5.7 5.0 3.4
992:.1 .10.7 6.4 6.1 7.9 8.1 7.7 7.7 6.8 7.1 6.0 5.5 4.7 2.9
9s11 8.5 6.7 6.4 7.5 7.2 6.9 6.4 4.9 4.7 4.8 4.4 3.7 2.1 i---84!±/--9.1-··7.1--7.1 8.3---7.-6--7.-1---6.6---4-.4--4.2---4.3 --4-.0-3.2 1.3
II Downstream of Devil Canyon Dam Site
2:.1 Upstream of Chulitna -Susitna confluence
1.1 Downstream of Chulitna -Susitna confluence
!f./At Sunshine Stream gagillg station 1
1
1
(
I
TABLE E.3.2.117:SUSITNA HYDROELECTRIC PROJECT
SIMULATED STREAM TEMPERATURES
STAGE III
WEATHER PERIOD:SUMMER 1982
CASE E-VI FLOW REQUIREMENTS
STAGED CONSTRUCTION
I 50 FT DRAWDOWN AT DEVIL CANYON
2 LEVELS OF PORTS
RIVER MAY JUNE JULY
MILE 31 32 33 34 35 36 37 38 39 40 41 42 43 44
15011 3.6 3.8 4.0 4.3 4.6 4.9 5.4 6.1 6.6 7.3 8.6 9.6 9.8 9.9
140 3.8 3.9 4.2 4.5 4.9 5.1 5.6 6.4 7.1 7.8 8.9 9.9 10.0 10.2
130 4.1 4.1 4.5 4.8 5.2 5.4 5.8 6.7 7.5 8.0 9.0 9.9 9.6 10 .0
120 4.4 4.3 4.8 5.1 5.7 5.8 6.1 7.2 8.2 8.6 9.5 10.4 9.9 10.5
110 4.7 4.5 5.2 5.4 6.1 6.2 6.4 7.7 8.7 9.1 9.9 10.8 10.3 10.9
992:.1 5.0 4.7 5.5 5.8 6.5 6.5 6.8 8.2 9.4 9.6 10.3 11.3 10.6 11.4
98]/4.9 4.5 5.4 5.5 6.3 6.6 6.2 6.8 8.5 8.1 8.3 8.8 8.0 8.7
84!i1 5.3 4.9 6.0 6.1 7.2 7.7 6.8 7.8 9.7 8.9 9.0 9.7 8.8 9.6
RIVER AUGUST SEPTEMBER·
MILE 45 46 47 48 49 50 51 52
1501/9.9 9;7 9.9 8.5 7.3 7.6 7.8 8.0
140 10.2 9.'9 10.1 8.7 7.5 7.6 7.7 7.8
130 10 .2 9.9 10.1 8.7 7.5 7.4 7.2 7.4
120 10.7 10.2 10.5 9.1 7.7 7.6 7.3 7.3
110 11.1 10.6 10.9 9.3 7.8 7.7 7.3 7.2
992:./11.6 10.9 11.2 9.6 8.1 7.8 7.4 7.1
98]/8.8 8.4 8.8 7.3 6.8 6.2 5.1 5.3
84!±1 9.5 9.1 9.5 8.1 7.3 6.5 5.5 5.1
1/Downstream of Devil Canyon Dam Site
11 Upstream of Chulitna -Susitna confluence
1/Downstream of Chulitna -Susitna confluence
!il At Sunshine Stream gaging station
TABLE E.3.2.118:MAXIMUM SIMULATED RIVER STAGES
FOR CASE E-VI FLOW CONSTRAINTS,
INFLOW TEMPERATURE-MATCHING,
AND WINTER 1981-82 CLIMATE DATA
NOTES:
1.[]~~~~~~;e:~~~~i~l~u~~e~~r:~h~idei~~:~i~~~ge equals or
2.All river stages in feet •.
Source:Exhibit E,Chapter 2.
1
J
,
1
1
j
~l
j
-1
1
1
j
!
I
1
I
1
(
1
787
I::~I
459
474
485
487
518
545
569
581
603
617
628
650
·656·
1668 1
684
715
729
Simulated
Stage III
Conditions
1-2
114
3-5
~~
457
472
1484 1
486
523
549
571
583
606
620
Simulated
Natural
Conditions
367
453
(Upland)
476
482
487
(Upland)
548
573
582
604
617
626
651
657
667
687
(Upland)
730
747
Threshold
Elevation
101.5
112.0
112.3
114.1
115.5
115.9
120.0
123.5
126.1
127.1
129.3
130.6
131.8
133.7
134.3
135.3
136.5
139.3
140.5
...J!+1.8 ...
River Mile
MSII West
MSII East
Curry
Moose
22 144.8 788
Whiskers
Gash Creek
6A
8
LRX-3 Ice Front Starting Date
Maximum Ice Front Extent (River Mile)
Melt-out Date
Slough or
Side Channel
8A West
8AEast·
9
9 u/s
4th July
9A
10 u/s
11 d/s
11
17
20
.21 (A6)
TABLE E.3.2.119:NATURAL AND ESTIMATED MEAN MONTHLY
SUSPENDED SEDIMENT CONCENTRATIONS
AND TURBIDITY VALUES EXPECTED TO
EXIT DEVIL CANYON RESERVOIR DURING
STAGE III OPERATION
Month
January
February
March
April
May
June
July
August
September
October
November
December
Observed Stage III Operation
Suspended Estimated Mean
Sediment Suspended Estimated
Concentra-Sediment Mean
tions.!!Concentrati onsl1 Turbidity
(mgl 1)(mg/l)NTu~1
<1-8 55 110
N.A.50 100
1-6 25 50
N.A.25 50
65-1,110 15 30
151-1,860 35 70
100-2,790 75 150
158-1,040 75 150
23-812 55 110
6-140 50 100
N.A.70 140
N.A.70 140
N.A.=Not Available
II Data derived Table E.2.4.73 (in Exhibit E,Chapter 2)
%1 Turbidity estimated by using factor of (2x)times TSS
concentrations (see discussions in Exhibit E,Chapter 2).
TABLE E.3.2.120:IMONTHLY MAXIMUM,!MINIMUM AND MEAN FLOWS AT SUNSHINE (CFS)
iSTAGE III -WATANA (HIGH)-DEVIL CANYON OPERATIONS
i !,
Month Natural Conditidns Early Stage III Flows Late Stage III Flows
l:1ax Min Mean Max Min Mean Max Min Mean
October 20,837 8,176 13,799 2q881 11,129 15,759 22,402 9,604 16,648
November 8,775 4,020 6,185 13 ~944 8,040 11 ,882 16,124 5,805 13,168
December 6,547 2,675 4,426 12 ~710 10,069 11,595 16,167 7,560 13,572
January 5,216 2,228 3,674 llP36 9,249 10,388 14,289 8,340 12,400
February 4,664 2,095 3,115 10~836 9,051 9,908 13,575 8,151 11,935
March 3,920 1,972 2,786 9~375 8,194 8,892 12,437 7,391 10,688
April 5,528 2,233 3,585 9~969 7,736 8,662 12,457 7,048 10,104
May 43:,121 10,799 27,674 37~862 13 ,481 21,874 40,342 13 ,000 23,258
June 116,152 40,702 63,268 77 ~405 33,066 44,695 77,926 33,055 45,827
July 85,600 45,226 64,143 73~890 37,295 52,891 65,761 37,295 49,148
August 84,940 25,092 56,148 82 999 24,031 52,775 68,817 24,031 44,996
September 54,110 14,320 32,867 54 110 15,983 32,722 47,235 15,983 30,077
ANNUAL 28,262 14,431 23,607 28 396 16,473 23,605 28,396 17,052 23,566
.~-'--c _
.-e.--J
TABLE E.3.2.121:MONTHLY MAXIMUM,MINIMUM AND MEAN FLOWS AT SUSITNA STATION (CFS)
STAGE III -WATANA (HIGH)-DEVIL CANYON OPERATIONS
Month Natural Conditions Early Stage III Flows Late Stage III Flows
Max Min Mean Max Min Mean Max Min Mean
58,640 13 ,476 32,777 59,829 16,807 34,664 60,590 18,428 35,553
31,590 8,251 15,063 35,538 13,605 20,789 37,990 11,370 22,075
14,690 5,753 9,267 21,261 12,959 16,453 24,723 10,351 18,430
Janua 10,120 6,365 8,112 16,688 13,217 14,828 19,885 12,426 16,840
Febru 9,413 5,614 7,383 15,877 12,785 14,176 19,204 13,280 16,203
March 8,906 5,271 6,412 14,756 11,526 12,520 17,847 11,105 14,316
April 13,029 4,613 7,684 17,672 10,113 12,897 20,021 10,960 14,338
May 88,470 28,713 56,770 80,229 20,902 50,935 81,866 22,479 52,318
June 165,900 73,838 112,256 136,737 52,305 93,641 138,236 54,878 94,773
July 181,400 92,511 126,590 167,898 82,662 115,302 156,910 82,662 111,560
Augus 159,600 80,891 109,084 157,203 79,830 105,704 143,603 73,221 97,925
Septe ber 109,700 37,592 67,721 109,195 39,255 67,667 100,258 36,183 65,022
ANNUAL 63,159 38,030 46,871 63,155 38,038 46,875 63,011 38,778 46,836
TABLE E.3.2.l22:JUVENILE CHINOOK REARING HABITAT
INDEX VALUES FOR MEAN MONTHLY DISCHARGE
AT THE SUNSHINE STAT IoNlI UNDER THE
NATURAL AND STAGE III OPERATING FLOW REGIMES
AGGREGATE HABITAT INDEX VALUE~I
Natural Flows Early Stage III Flows Late Stage III.Flows
Side Tributary Side Tributary Side Tributary
Month Channels Mouths Channels Mouths Channels Mouths
June 0.028 0.140 0.050 0.055 0.050 0.055
July 0.027 0.142 0.036
0.110 0.040 0.070
August 0.035 0.120 0.036 0.110 0.05 0.055
September 0.040 0.055 0.040 0.055 0.035 0.051
II From Table E.3.2.ll7
J
'\
1
\
I
J
l
\
]
1
I
I
·1
~~---------
TA LE [.3.2.123:IMPACT ISSUES AND PROPOSED MITIGATION FEATURES FOR ANTICIPATED FILLING AND
OPERATIONAL IMPACTS TO AQUATIC HABITATS,SUSITNA HYDROELECTRIC PROJECT
OCCURRENCE MITIGATION FEATURE
Watana Watana
IMPACT Development Devil Canyon Development .Devil Canyon
ISSUE (Both Stages)Development (Both Stages)Development
Filling Operation Filling ,Operation Filling Operation Filling Operation
Pass ge of Adult X X X X -Minimum flow -Minimum flow -Minimum flow -Minimum flow
Salm n requirement requirement requirement requirement
Impa bts to X X X X -Minimum flow -Minimum flow -Minimum flow -Minimum flow
Slou bh Habitat requirement requirement requirement requirement
-Slough modi--Slough modi--Slough modi-
fication fication fication
Loss of Side-Channel X X X -Modification -Modification -Modification
and Mainstem Salmon of side of side of side
Spawhing Areas channels channels channels
AlteIred Thermal X X -Multiple le--Multiple le-
Regi me vel outlet vel outlet
Gas ~uperaturation X X X -Fixed cone Fixed cone -Fixed cone
valves valves valves
Inur dation of X X -Improved -Improved
Trit utary Habitat access to access to
fishing area fishing area
-Habitat -Habitat
improvement improvement
Out migration of X X X -Minimum flow -Minimum flow -Minimum flow
Jun'enile Anadromous requirement requirement requirement
Fist
TABLE E.3.2.124:ESTIMATED COST FOR WATER QUALITY AND FISHERIES MONITORING
(IN 1985 DOLLARS)DURING CONSTRUCTION (1986 to 2012)
II :lnclude.sSt,age I on1)1
2:.1 Includes Stages I and II
11 Includes Stage III
Field
Field Labor Equipment
I
1
1
!
1
)
.J
]
]
J
\
.]
1
l
I
'j
!
1
I
I
Total
(xlOOO)Travel
10,000 287.5
12,500 290
5,000 170
5,000 170
26,000 480
15,000 615
15,000 615
10,000 450
5,000 305
10,000 1,060
10,000 890
10,000 890
5,000 665
2,500 297.~
2,500 297.5
2,500 297.5
..l,.5Q..Q 297.5
2,500 297.5
2,500 297.5
2,500 297.5
2,500 297.5
2,500 297.5
2,500 296.5
2,500··-····2·97.·5
·-2,500·--.-....2·97.5
2,500 257.5
TOTAL $11,605.0
AVERAGE ANNUAL 429.8
7,500
7,500
30,000
20,000
20,000
5,000
10,000
10,000
10,000
10,000
10,000
5,000
5,000
5,000 .
..2,Q.OO.
5,000
5,000
5,000
5,000
5,000
5,000
-·--·5,000··.
·5,-000-
5,000
150,000
150,000
75,000
75,000
255,000
340,000
340,000
255,000
170,000
680,000
510,000
510,000
410,000
170,000
170,000
170,000
...17!LQOO .
170,000
170,000
170,000
170,000
170,000
170,000
..··-170,000
·'170.,000
130,000
120,000
120,000
90,000
96,000
180,000
240,000
240,000
180,000
120,000
360,000
360,000
360,000
240,000
120,000
120,000
120,000
12Q,QQQ~.
120,000
120,000
120,000
120,000
120,000
120,000
·····120·,000··
'120,·000 .
120,000
ManagementYear
198611
198711
198811
198911
199011
199111
199211
199311
199411
19952:.1
19962:.1
19972:./
19992:.1
20002:.1
20012:.1
20022:.1
20o~1
20042:.1
200sl1
200611
200711
200all
200911
._--....······2010~/
.........·zo·n:2.1
201211
TABLE E.3.2.l25:ALASKA DEPARTMENT OF FISH AND GAME
STANDARDS FOR BLASTING NEAR AN ANADROMOUS
FISH STREAM MEASURED IN FEETll
Explosive Charge Weight in Pounds
Substrate 1 2 5 10 25 100 500 1,000
Rock 50 80 120 170 270 530 1,180 1,670
Frozen Material 50 70 110 160 250 500 1,120 1,580
Stiff Clay,Gravel,Ice 40 60 100 140 220 440 990 1,400
Clayey Silt,Dense Sand ~40 50 80 120 180 370 820 1,160
Medium to Dense Sand 30 50 70 100 160 320 720 1,020
Medium Organic Clay 20 30 50 70 100 210 460 660
Soft Organic Clay 20 30 40 60 100 190 440 620
II Required distances for charge weights not set forth in this table must
be computed by linear intropolation between the charge weights bracketing
the desired charge if the charge weight is between one and 1000 pounds;
example:for 15 pounds of explosive in rock substrate -required
distance =170 feet +15 lbs-10 lbs (270 feet-170 feet)=203 feet;
25 lbs-10 lbs
for charge weights greater than 1,000 pounds,the required distance may be
determined by linear extropolation.
Source:Edfelt 1981
TABLE E.3.2.l26:PROPOSED FISHERIES MITIGATIONS WITH ESTIMATED
CAPITAL AND ANNUAL OPERATING AND MAINTENANCE COSTS
Mitigation Feature
Capital Costs
Total
Annual Operating and
Maintenance Costs
Downstream Mitigationl/
Protective Slough Berms
Restructured Slough Mouth
Lowered and Restructured
Slough Profile
Wing Deflectors
Bank Stabilization
Rock Weirs
Log Barriers
Total
Impoundment MitigationZ/
Public Access Acquisition
Habitat Improvement
Total
Dam Structuresl/
,_Mu_LtipLe~LeJl..ELLlntakes .'_'._
Cone Valves -Watana (6 valves)
Cone Valves -Devil Canyon (7 valves)
347,000
52,000
224,000
288,000
25,000
98,000
54,000
$1,088,000
650,000
290,000
940,000
000
47,100,000
14,600,000
----
Total $30,000
N/A
20,000
Total 20,000
N/A
NTA
N/A
!
,'J
.,..-;
Total $80,100,000
Total for Fisheries Mitigation $82,128,000
--iICOsting"'detaiTsate itiWCC--1-984aan-dTableE;3;2;128--
--1:/Co-st-sare-based'onprima-ry-mi:-ti:-gation opt-ions------
l/Costing details are in Exhibit D
Annual 0 &M $50,000
1
l
1
.J
'J
TABLE E.3.2.127:ARCTIC GRAYLING POPULATION ESTIMATES
IN SELECTED TRIBUTARIES OF THE WATANA
IMPOUNDMENT ZONE
Tributary
River
Mile
Estimated Estimated Tributary Estimated Number of
Grayling Miles Inundatect21 Grayling in Inundated Reach
per Mil~Stage 1 Stage 3 Total Stage 1 Stage 3 Total
Deadman Creek 186.7 1,83~2.0 0.7 2.7 3,670.1,285 4,955
Watana Creek 194.1 324 7.5 4.3 11.8 2,430 1,393 3,823
Kosina Creek 206.8 1,232 2.8 1.7 4.5 3,450 2,094 5,544
Jay Creek 208.5 455 2.1 1.4 3.5 955 637 1,592
Goose Creek 231.3 791 0.0 1.2 1.2 0 949 949
Oshetna River 233.4 1,103 0.0 2.2 2.2 0 2,427 2,427
Total 14.4 11.5 25.9 10,505 8,785 19,290
J/Modified from ADF&G 1983b Beyer-9.
l!Assumes reservoir levels at probable maximum flood stage:Stage 1 Watana =el.2020.
Stage 3 Watana =el.2,200.5.
11 Estimated grayling per mile in Deadman Creek was calculated by ADF&G (1983b)for the
reach of stream blow the falls (0.3mi).Extrapolation of grayling per mile to total
length of stream inundated is likely an overestimation of grayling population size.
Source:ADF&G 1983b.
1/Assumes reservoir level at probable maximum flood stage =el.
1,466.
TABLE E.3.2.128:ARCTIC GRAYLING POPULATION ESTIMATES
IN SELECTED TRIBUTARIES OF THE
DEVIL CANYON IMPOUNDMENT ZONE
Tributary
Fog Creek
Tsusena Creek
Total
River
Mile
176.7
.181.3
Estimated Tributary.
Miles Inundatedl1
1.3
0.4
1.7
Estimated Number of
Grayling in Inundated Reach
176
1,000
1,176
l
1
1
I
J
,J
1
J
.1
J
l
I
I j
J
,j
J
J
·r
TABLE E.3.2.129:ANNUAL OPERATING COSTS OF LONG-TERM
MONITORING PROGRAM IN 1985 DOLLARS1/
I ]
11
IJ
Task
Management and Analysis
Adult and Smo1tl/Enumeration
Slough Modification
Resident Fish
Water Quality
Contractual Services
Materials
Repair and Maintenance of Equipment
Administration and Support Costs
Average Annual Fisheries
Monitoring Costs
Total Project Cost
Costs
$200,000
500,000
90,000
50,000
50,000
75,000
50,000
30,000
175,000
$1,220,000
$49,250,000
I
,
J
!/Costs are based on the estimated level of effort required to perform
the monitoring studies.These costs are exclusive of those for
construction related monitoring.
~/Assumes fishwhee1s at Sunshine and Curry and a smolt trap at Curry.
Assumes that Annual Cost will drop to $750,000 after 25 years due to
increased efficiency and lack of impact on certain species.
TABLE E.3.2.l30:SUSITNA ~YDROELECTRIC PROJE~T SCHEDULE FOR LONG-TERM AQUATIC MONITORINGPLANl/
Study Element
Prior !
Dat~Il~85 11986 119188 I 1989
Ava1l.~S S F W S S F W ~S F W S S
Stage I
1990 I Watana
FIW S S F Complete
Stage II
Devil Canyon
Complete
Stage III
Watana
Complete
Complete
Project
+5 years
yes I -~---.
yes I --------
yes
no I
yes I --------
Water Quality
1.Dissolved Gas
Supersaturation
2.Temperature/Ice
Turbidity/Sediment
3.Mercury/Heavy
Metals
4.Dissolved Oxygen,
pH,Organic Nitro-
gen,and Phosphorus
Water Quantity yes
----------_.-------)
I.I I I ..)I !I I I I I _i--~---------------~--------------------------------
Fish Resources
Structural Habitat
Mod1f1cat1ons
Fluvial Geomorphology
Spetial Monitoring
Studies
yes
yes
---
(I~.incrrporate4 a.par
I I I I
(p~rfo~ed on an a~-nee
!I I·:
of mitrationl
ed basis)
-------)
------)
'------)
Project Schedule (milestones)
License Granted
Stage One
Watana Main Access Begins
**
*
I
W S S F -~inter,Spring,Summer,Fall
,l/Based on the project schedule presen edi in this license application amendment
J!fL,~
L-,---.i _
~
TABLE E.3.2.131;r SUMMARY OF ESTIMATED COSTS FOR HABITAT MODIFICATION MEASURES IN SELECTED SLOUGHS AND SIDE CHANNELS •
......-.'.....
Slough 8A .Slough 9 Slough 9A Slough 11 USC 11 Slough 21 Side Channel 21 Total
Capital Capital Capital Capital Capital Capital Capital Capital
Costs O&M Costs O&M Costs O&M Costs O&M Costs O&M Costs O&M Costs O&M Costs O&M
I
Slough Mouth
Exe ...tion j 26,000 26,000 ,.'52,000
Wi ng Defl ecto 24,000 24,000 240,000 288,000
Passage Reach
Excavations 10,000 7,000 17,000
Protective
Berm 61,000 59,000 42,000 24,000 161,000 347,000
Log Barriers 30,000 24,000 54,000
Bank
Stabil hatton 25,000 25,000
Rock Weir 37,000 61,000 98,000
Total Slough
Excavations I 76,000 26,000 26,000 34,000 45,000 207,000
~
Total I 121,000 4,000 159,000 4,000 118,000 4,000 184,000 4,000 187,000 4,000 34,000 5,000 285,000 5,000 1,088,000 30,000
TABLE E.3.2.l32:SCHEDULE FOR IMPLEMENTING AQUATIC MITIGATION PROGRAM ·1
Mitigation Measure
Construction Mitigation
Project Phase for
Implementation
Year of Implementation
Final
Planning Construction
1
Preconstruction Design
and Planning
Construction Monitoring
Operational Mitigation
Downstream Mitigation
Protective Slough Berms
Slough Mouth Excavation
Lowered and Restructured
Sloughs
Final Design
Watana Stage 1 Construction
Watana Stage 1 Construction
Watana Stage 1 Construction
Watana Stage 1 Construction
1986
1986
1986
1986
1986
1989
1989
1989
1989
Impoundment Mitigation
Public Access
Acquisition
Habitat Improvement
Multiple Level Intakes
Cone Va lves
Operational Monitoring
Final Design 1986
Fina 1 Design 1986 1989
l--Watana Stage 1 Fi lling 1986 1996 --
Devil _G~l1YQn F'~lUllg 1991 1995
Watana Stage 1 Filling 1986 1996 ]
Devil Canyon Filling 1991 1995
Watana Stage 1 Fi lling 1986 1996
.J
I
FIGURES·
·1
)
FIGURE E.3.2.1
~o
()'.d"O •
~
Em:e,.
Creek
",
\
\
\
\
\MIDDLE DRAINAGE,
~°f~/"~--------',",,/,",'",--....",...........,,'",----"",
I
I
I
,/
/
/
//
",,,'",
SUSITNA ....."\~6
lRM 26.0)".....~
"""""/
I
I
I
LOWER DRAINAGE BASIN
20
LOWER DRAINAGE BASIN--...."."
,//"
,/"
,,'/""",
"\
\
\
,/
/
I
I
I
I
I
I
.SUSITNA RIVER .......//
DRAINAGE BASIN /
,,"/
,,"/
,,,,,,,,,,,,
~,",,""-~",....
","
,/",
//
I
I
I
I
I
UPPEIR.MIDDLE.AND LOWER DRAINAGE OF THE SUSITNA PROJECT AREA.
/
I
/
I
/
o
SUSITNA RIVER AND MAJOR TRIBUTARIES
FROM MOUTH TO LITTLE WILLOW CREEK
,)
]
,I
f
,I
.J
:.1
I)
'i
J
l
,\
.j
("1
"
FIGURE E.3.2.2
/,./ANCHORAGE
,...,r-'----t...-t-_..J
COOK INLET
FlATHORN
STATION
0
(RM 22)
10 Miles
0 5 10 15 Kilometers
0 ...5-----;,10 Miles..)
I
J
o 5 10 15 Kilometers
SUSITNA RIVER AND MAJOR TRIBUTARIES FROM
MONTANA CREEK TO DEVIL CANYON FIGUREE.3.2.3
Rive,.
~
o 5"10 Miles
~J~-.
o 5 10 15 Kilo"meters
(U7(/
StlJSITNA RIVER AND MAJOR TRIBUTARIES
FROM DEVIL CAN'l'iON TO DENALI HIGHWAY1:FIGURE E.3.2.4
"."----""---:
...
1981 1982
CHINOOK ._--49,800
SOCKEYE 133,000 151,000
COHO 19.800 45,700
CHUM 263.000 430.000
PINK 49.500 443,000
1983 1984
CHINOOK 90.100 121,700
SOCKEYE 71,500 130.100
COHO 15,200 94,700
CHUM 265,800 765,000
PINK 40,500 1,017,000
1984
605.800
190.100
812,700
3,629.900
CHINOOK
SOCKEYE
COHO
CHUM
PINK
1981 1982 1981 1982
10,900 DEVil CANYON CHINOOK ---11,300
4,800 3,100 SOCKEYE 2,800 1,300
3,300 5,100 COHO 1,100 2,400
20,800 49,100 CHUM 13,100 29,400
2,300 73,000 PINK 1,000 159,000
1983 1984 1983 1984
--------
CHINOOK 9,700 18,000
SOCKEYE 1,900 3,600
COHO .800 2,200
CHUM 21,100 49300
PINK 5,500 116:900
149,400
18,200
26.500
369,300
1981 1982
04.400
8.900
10,800
60.700
39,000
17,000
19,800
136,100
,1983 1984
CHINOOK
SOCKEYE
COHO
CHUM
PINK
CHINOOK
SOCKEYE
COHO
CHUM
PINK
8OURCE:AOF&G t198Sb
POPULATION ESTIMATES OF ADULT SALMON IN SUSITNA RIVER FIGURE E.3.2.5
BELUGA R.
I.'S~SlrNA R.LITTLE FISH CRE.~~.~'MAllINUSKA R.
I
'."'.!I:II SUSITNA R.~-KNIK .--:.;,,......,-".,"V..,...,,;,t'
I I '.J"::'J !",,-..,
[i CHIJITNA R.i .>.,..j ,...J'...1/---
I
'....V·-....
CHAKACHAT I •'y-'I /J r:;.'-.NA~.I .[NORTHERN V',ANCHORAGE
McARTHUR R "_.,"r.J0"'-"·0lSrR1CT .........'\TURNAGAIN "''\...
KUSTATAN R
1
.Vi''/'-''-ARM --•• 1 '~---,. .\'..'.....
BIG R ~~:/.,-...../...........'\..."'-
..1\I ""'
ORIFT R.\~\•••--1'"--"::';'"
"'"~"'i.i '.,;J .'''\,,'.rdE I .,..EAST I "
)/,NjI'RAL •FOREjLANO
(
'"[DISTRICT \I •:f1i ~I
CRESCENT R ,,.S jJ I I ,f-......
TUXEONI '\../I 'A KENAI R.BAY::::-···~.·~..~-',.,:I!):'..\
".i"I I"\~i ,';'\1.1
'>..i./..-KASIL\>F R.
:'..I/i CEFAL DISTRICT I [i
""'"'TNA ....-/••,'!
BAY-:-..VJ}i l
:;l.,NCHOR PT.
i·.:
UPPER COdK INLETCOMME~CIAL SALMON MANAGEMENT AREAI'FIGURE E.3.2.6
4.;''---
ACTIVITY
JAN FEB MAR APR MAY
MONTH
JUNE JUL AUG SEP OCT NOV DEC
CHINOOK
ADULT PAstGE
SPAWNING
INCUBATION EMERGENCE
REARING
SMOLTING
I I I I..•.........
II.•I I .....
~....I "'11I'I I I aI
.....1-eM It....
PINK
ADULT PASSAGE
SPAWNING
INCUBATION ~EMERGENCE
OUTMIGRATlON
~I • I I .d •••••••••••
••~...I •••
...........
•..1 ..-.......
...+0-I I I I
CHUM
ADULT PAS GE
SPAWNING
EMERGENCE
REARING
I I I I .....•.....
•••I I •••••••••
.u I +rll ...
~....-..
....+OM I I I I
LEGEND:
__III INTE~SE ACTIVITY
.........MODaRATE ACTIVITY
...." • I ....
TI MING OF LIFE STAGES OF SALMON IN THE SUSITNA RIVER
FROM TALKEETNA TO DEVIL CANYON
SHEET I OF 2
SOURCEl AOFllG ISqlo.I58ld.19830.IS83m.IS84c.1984h.
ISaillb.191111CI MORROW 1980 FIGURE E.3.2.7
ACTIVITY MONTH
•
JAN FEB MAR APR MAY JUNE JUl AUG SEP OCT NOV DEC
!;
COHO i
'ADULT PASSAGE i .......j
'SPAWNING
i ....
i INCUBATION/EMERGENCE
j
....10.................
I
:REARING
I',c
SMOlTING .n...01..
SOCKEYE I
i i
•ADULT PASSAGE i .......i
.SPAWNING i .........
,INCUBATION/EMERGENCE i .,.....111 ....1 ......I
REARING ......II .IOB
I
:OUTMIGRATION it •un......
i i
;!
*1 JUVENilE SOCKEYE APPEAR TO BE ABSENT FROM ITHis REACH
lEGEND:tI!
INTENSE ACTIVITY
..0 ......MODERATE ACTIVITY I !
i I
i ,!
!i I
I
I '
i i !
TIMING OFI LIFE STAGES Off SALMON IN THE SUSITNA RIVER
I F.ROM TALKEEtNA TO DEVIL CANYON
!I I
i I SHq:ET 20F 2
FIGURE E.3.2.7
84
129
2
6 0
81 82
Slough 2
Slough 1
27 0 49
o 0 0
81 82 8"S
--'1...-_Slough 1
Slough 3A
81 82 83 84
Sockeye 7 0 0
1 1
Pink 1 0 0 56
Chum 0 0 0
17
'.
84
A MATCHllNE
~o
Slough 38
1 0 5
o 0 0
o 0 3
Slough 3B
81 82 83
Whiskers Creek -,
81 82 83
1 0 0
1 138 0
70 176
o 0
Whiskers Creek
a River Mile
Sockeye
Pink
Chum
Chum
Pink
Coho
Chinook
SLOUGH AND TRI BUTARY INDEX AREA
PEAK SPAWNING COUNTS
!iOUflU:ADF a G 19810,19830,1984h,1985b
FIGURE E.3.2.8
.(
1
1
J
1
]
j
Slough 6o
1
4
1
o
o
2
o
o
Chum 0
Sockeye 0
Pink 0
Cha.e Creek
81 82 83 84
Chinook 0 15 15 3
Chum 79 0 0 1
Pink 38 107 6 438'
Coho 80 36 12 239 A MATCHLINE
]
Slough 8
81 82 83 84
Chum 302 0 0 65 1Pink250 0
1
Sockeye 0 0 0 2
1
Lane Creek
81 82 83 84
\Slough 8 Chinook 40 47 12 22
Chur,n .76.1 1 6 31
Pink 291 640 287 1184 ICoho3 5 2 24
IGashCreek
81 82 83 84
0 Coho 141 74 0 234
1Slough6A00196
Cl R,,'!!r .\1';,'.1
Slough 6A
81 82 83 84
Chum 11 2 6 0
Sockeye 1 0 0 0
Pink 0 35 0 0
Coho 0 35 0 0
SLOUGH AND TRIBUTARY INDEX AREA
-SOURCE:-ADFaG l~~~h,'r:i~~PEAK SPAWNING COUNTS FIGURE E.3.2.9
o~C MATCHLJN_E__-=~~-=-=~_Slough 88
81 82 83 84
84
121
o
1
84.
23
585
24
4
o
o
83 .
83
1
28
18
o 48
o 2
o 0
81 82
81 82
14 0
1 23
58 133
81 82 83 84
Lower McKenzie Creek
McKenzie Creek
Slough 8C
81 82 83 84
Chum
Sockeye
Pink
Chum
Pink
Coho
Little Portage Creek
Chum 0 31 0 18
Pink 0 140 7 1 82
Coho 0 8 .0 0
Pink 0 17 0 11
Slough BC
Lower Me KenzIe Creek
-lillIe Portage Creek
\<1._-Slough aD
o 23 1
81 82,83
RM 115 IRKm jH.'i)
Slough 80
Chum
o
SLOUGH AND TRIBUTARY INDEX AREA
PEAK SPAWNING COUNTS
SOlJRC£:ADF8G 1~~~,'983o,1984h,FIGURE E.3.2,IO
SLOUGH AND TRIBUTARY INDEX AREA
PEAK-SPAWN ING-COUNTS--SOURCE:ADF8G 19810,19830,1984h,1985b
]
J
I
I
I
I
J
1
]
r
1
1
1
'j
!
I
'l
l
FIGURE E.3.2.11
140 0 77 111
o 0 0 24
.Chun'l
Pink
0 MATCHLINE
ShEtrman Creek
81 82 83 84
Chinook 0 3.0 0
Chum 9 0 0 6
PInk 6 24 0 48
Slough 9B
81 82 83 84
90 5 0 73
81 1·0 7
Slough 9
81 82 83 84
Chum 260 300 169 350
SOckeye 10 5 2 6
PInk .0 12 0 1
SloUgh B
81 82 83 84
Chum 0 0 7 108
SOckeye 0 0 2
9
Slough 8A
81 82 83 84
620 336 37 917
177 ·68 66 128
O·28 0 134
---0~---4-.-0-.-0--
8A
Slough A
8t 82 83 84
Chum 34 O·2 2
PInk 2 0 0 0
- -Slough A
-Skull Creek
~r-A_'----S-I-O-U-9-h--A-~t----...,
81 82 83 84
o
76
8
25
84
84
17
2
411
84
92
193
1842
8
1 0
12 1
82 83
Creek
83
6
148
78
3
Creek
81
10
8
Fourth of July Creek - " -
Skull
82
56
191
702
"4
RM 130 (RKm
July
o 3 0
o 1 6
2 113 9
81 82 83
of July Creek
81 82 83
o 1 0
167 23 68o8.22o a 0
Chum
Pink
81
4th of
·····5·th:of July Greek ----'l..:~1
Moose Slough
5th
Chinook
Cht,Jm
Pink
Chinook
Chum·.
SOCkeye
Pink
Chinook
Chum 90
Pink 29
Coho 1
Slough 9A
81 82 83 84
Chum 182 118 105 303
Sockeye 2 1 1 0
MATCHt.'INE
Slough 10
81 82 83 84
Chum 0 21 36
Sockeye 1 0
Slough 20 SlOugh 19
81 82 83 84 81 82 83 84
Chum 14 30 63 280 Chum 3 0 3 45
Sockeye 2 0 0
0 Sockeye 23 0 5 11
Pink 0 64 0 85 Pink 0 1 0 0
-Slough 20
Slough 17
81 82 83 84
Chum 38 21 90 66
Sockeye 6 0 6 16
Pink 0 0 0 1
Indian River
81 82 83 84
Slough 16
Chinook 422 1053 1193 1456.81 82 83 84
Chum 40 1346 722 2247 3 0 0 15
Pink 2 738 886 9066
Coho 85 101 53 465
Sockeye 0 0 1 1
Gold Creek
Slough 16 81 82 .83 84
21 23 23
SLQugh 15 -0 11 7 82
0 1 0 0
Slough 15
81 82 83 .-Gold Creek
Chum 1 1 2
Pink 1 132 0
Coho 0 14 GOLD CREEK STATION
Sockeye O·0
-Slough 11
Slough 13 Slough 11
81 82 83 84 81 82 83 84
Chum 4 0 4 22 Chum 411 .459 238 1586
Sockeye 893 456 248 564
Pink o 131 0 121
SLOUGH AND TRISlJ.1ARY INDEX AREA
SOORCE:AOFaG 19810,198'3o,I984h,l98l5b PEAK SPAWNING COUNTS FIGURE E.3.2.12
Portage Creek I
1
I
.'!
1
l
I
1
'I
.J
'1
J
(
7
4
14
6
84
84
2341
1285
12
2707
128
FIGURE E.3.2.13
..2 6
o 3 2
t 21 5
o 1 1
81 82 83
81 82 83
659 1253 3140
o 153 526
o 4 0
o 169 285
22 88 15
deck Long Creek
Chinook
Chum
S.ockeye
Fink
Coho
Portage Creek --
83 84
319 2354t5 ·
197--1-2-2-.
o 8
81 82
"274 "736
38-53o64
Slough 21
84
10
Chum-
Sockeye-
Pink
83 84
o 2
114151
SLOUGH AND TRIBUTARY INDEX AREA
PEAK SPAWNING COUNTS
8 0 0
81 82 83
81 82
Slough 22
E MATCHLlN,E
.Slough 21 A
Chum
o ":"'t"\11i..
o
-.Slough.22 -.---::
Sockey.,O.0
Chum 0 0
S9'Jf1ce:.A[)F ~GI98IQ.J9~Q.1.9.'!4h.•..1.98Db
a I
l---J.....
"'""O~1!I0·.U HYORO ACeas.,CORRIOOR STREA"N..,.aER
e..CORRIOQR "I~a:
!1a CllmN8 ~""u
...·.PItOPOSID WATAIU ACCUS C"UtiOON
Stream crossing sites aiong the northern portion of the
proposed Watana Access corridor.
SOURCE:ADF & G 19840
FIGURE E.3.2.14
,,
'f ........
i--r--··--
;/_....._...
111"'11
o I
'----JMILt:
-<i.-~:~&;~U~i:.'H'ifJ:iR--·
CM CORRIDOR NILE
~EXISTING LARES
_PROPOSE~OIVlL CAH'I'OII ACCCS CORRIOOlI
-PROPOSED .....TANA ACCESS CORRIDOR
AD'."SU tf'(OlllO-3/2"1'"
-1
Stream.crossing sites along the southern portion of the
proposed watal'la access corridor,il'lcH.ldi ri9threestlJdyreathes
of Deadman Creek.,1
SOURCE~ADFB.G 19840 FIGURE E.3.2.15
j
o I
I I
...L[
!t!J a8Gtft8o\U Jt~~~?.1'bAM~lffiSSION
®~g~:I~OS~rJ~:f,l~3~tiR
CM CORRIDOR NILE1mEXISTlllGLAKEa
- -PROPOSED TRANSNISSION CORRIDOR
PROPOSEO DEVIL CANYON ACCESS CORRIDOR
.•-PROPOSED WATANA ACCESS CORRIDOR
AOf 0 a/su HYDRO -~12~/B4
(p
,p
oC7(]
FIGURE E.3.2.16
Stream crossing sites along the eastern portion of the proposed Devil Canyon access
and transnrission corri~ors.
SOURCE:ADF a G 19840
o~.-J
t
++OOLD CRUll RAILROAD CORRIOOR
""ADf 6 G-au HYDRO TRANSMISSION
UIJ CORRIDOR STREAIII HUIllDEH
@ M:RIMR-1MX~R~u.i'Bi~ElS
eM CORRIDOR IlILEmEXISTINGLAKES
___PROPOSED TRANSMISSION CORRIOOR5
--PROPOSED DEVIL CANYOfl ACCESS CORRIDOR
_0 _ANCHORAOE I fAIRBANKS I"TERTIE
AOfAe/lu HYDAO ·111418.
Stream cros~il~g sites along the western portion of the proposed Devil Canyon access and
transmissiop ~orridors,and the proposed Gold Creek rail access corridor.
i i
SOURCE:ADF f 119840 FIGURE E.3.2.17
---'~'-------,---'---------'
I 1I]
1\L_
FIGURE E.3.2.18
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
A T 23,000 C F S (T 0 P)AND.1 2,500 C FS (BOT TOM)
LEGEND:
+=RIVER MILE
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUTARY MOUTH SOURCE:EWT&A 1984 RIVER MILE 101 TO 102
J,~
:1
!.j
Il
I.]
\1
!!
:j
)
j
]
j
'I
I
]
J
rI
[I
LEGEND:FIGURE E.3.2.19
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (T 0 P)AND.1 2,500 C FS (80 T TOM)
+=
MS =
SC =
SS =
US =
TM·=
RIVER MILE
MAIN STEM
SIDE CHANNEL
SIDE SLOUGH
UPLAND SLOUGH
TRIBUTARY MOUTH SOURCE:EWT&A 1984
RIVER MILE 102 TO 104-
. I
i
!.!
I
I.
f
I
(
ii,
t
I
I
\
"r~...,.
I
f:
I
r
!,
,j
,
]
,J
"1
I )
,.J
,1
.1
I
'.J
.J
j
I
I
]
j
-j
]
1f
J..
lJ
DELINEATION OF H.A.BITAT AREAS IN THE MIDDLE SUSITNA RIVER
1,
..1
LEGEND:
I +=RIVER MILEl'
MS =MAINSTEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
SOURCE:EWT&A 19$4
FIGURE E.3.2.20
AT 23,000 CFS (TOP)AND.12,500 CFS (BOTTOM)
RIVER MILE 105 TO 107
L
---~-----~-~~-----------------~--------------------------------
j
{
i
I
(
xc
I
I
I
I
LEGEND:
MS =
SC =
SS =
US =
TM =
MAINSTEM
SIDE CHANNEL
SIDE SLOUGH
UPLAND SLOUGH
TRIBUTARY MOUTH
SOURCE:EWT&A 1984
LINEATION OF HABITAT ABEAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND.12,500 CFS (BOTTOM)
.RIVER MILE 108 TO 110
J
t
-1
J
'i:J:'
Ii
• f I'(
)i (,.
I
,1
I J
1l
,1f
\
J
t JL
;\
&
\
JI
I
(II
II
1 lI
!
I
1
I
J
J
J
[
FIGURE E.3.2.22
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND.12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
=MAINSTEM
SC =SIDE.CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUTARY MOUTH
SO URGE:EWT &A 19-84 RIVER MILE 110 TO 112
"1
';
...:::1
"
J
I 11
I\i
1
i
1~,
1~;
!,
t
"-t
Ii
"
';,~!
I 7~
(,
/i
!
J ('(..'
I!
,
)
I:,1I'I
I
f f
1 J
if
\!
j
).I[
!
/
II
I:)
)'1r
}
r
LEGEND:
+=RIVER MILE
MS =MAIN STEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH SOURCE:EWT &A 1984
FIGURE E.3.2.23
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND 12,500 CFS (BOTTOM)
RIVER MILE 113 TO ..115
)
)
FIGURE E.3.2.24
I
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
I
AT 23,000 CFS (TOP)AND.12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
MS =MAINSTEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
SOURCE:EWT&A 1984
RIVER MILE 116 TO 118
!
I
I
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r
\
I
!
I
I
1
]
1
]
I
)
1
OJ
1
J
1
J
]
j
j
1
}
1
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
FIGURE E.3.2.25
AT 23,000 CFS (TOP)AND 12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
MS -MAINSTEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
SOURCE:EWT&A 1984 RIVER MILE 119 TO 121
I
It
I
!
I
)
,}
,)
,J
1
J
1
,l=====~=========t=====------------}
"I
.,,
'r.":~":J
}
"J
il
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
FIGURE E.3.2.26
AT 23,000 CFS (TOP)AND.12,500 CFS (BOTTOM)
LEGEND:
I +=RIVER MILE
I.
MS)=MAINSTEM
SC =SIDE CHA.NNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
SOURCE:EWT&A 1984 RIVER MILE 122 TO 124
1
J
I
)
]
.1
J
]
J
1
l
..f
1
-J
J
}
1
1-=-====-=====;..~._--1
FIGURE E.3.2.27
AREAS IN THE MIDDLE SUSITNA R R
CFS (TOP)AND,12,500 CFS (BOTTOM)
LEGEND:
+=RIVER 'MILE
MS =MAINSTEM
SC =SIDE CHANNEL
SS =SIDE S'LOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH SOURCE:EWT&A 1984 RIVER MILE 124 TO 126
·)
1
)
,J
I
il
:}
j
I
,J
1
J
l
.J
--_.........._----
J
)
]
,1
J
r
FIGURE E.3.2.28
AREAS IN THE MIDDLE SUSITNA RIVER
CFS (TOP)AND 12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
MS =MAINSTEM DELINEA TION OF HABITAT
SC =SIDE CHANNEL AT 23,000
SS =SIDE SLOUGH
US =UPLAND SLOUGH SOURCE:EWT&A 1984
TM =TRIBUTARY MOUTH
RIVER MILE 127.TO 129
)
.J
J
1
1
j
l
J
'l
j
1
.J
]
J===========f--=-~----1
J
]
1
J
.J
t·
(,
t
Ir
I
\
I,
FIGURE E.3.2.29
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND.12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
MS MAIN STEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUTARY MOUTH
SOURCE:EWT&A 1984 RIVER MILE 130 TO 132
II
t
!
,I
(
\
i,
,1
1
]
J
1
1
)
]
]
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
FIGURE E:3.2.3.0
AT 2 3 ,000 CF S (T 0 P)AND.1 2,500 C FS (BOT TOM)
LEGEND:
+=RIVER MILE
MS =MAIN STEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
SOURCE:EWT&A 1984 RIVER MILE 133 TO 136
I
I
1g
I
J~,
r
[
,,
~
:]
;J
J
J
:1
, J
I
,\
!1
:J
, J
,']
j
'J
J
']
;l
I J
i 1
FIGURE E.3.2.31
RIVER
(BOTTOM)
136 TO 138RIVERMILE
MIDDLE SUSITNA
AND 12,500 CFS
AREAS IN THE
CFS (TOP)
OF HABITAT
AT 23,000
DELINEATION
SOURCE:EWT&A 1984
LEGEND:
+=RIVER MILE
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
J
f
'J
J
]
1
!
I
J
]
1
1
~~~-----~-~~------~------------~---J
r
J
.]
]
,1
r
I~
I
1
r
'(
i
1
I
1-j
~-------------------I
1
I
FIGURE E.3.2.32
139 TO 141RIVERMILE
MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND 12,500 CFS (BOTTOM)
SOURCE:EWT&A 1984
LEGEND:
I +=RIVER MILE
j MS =
SC =SIDE·CHANNELI
\SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUT ARY MOUTH
)
•I
,]
,J
]
}
]
I 1
~
I
:}
,]
·J
:1
._,;~--~--___.._~---~._---_.•.
1
: J
i]
l
':J
i I
FIGURE E.3.2.33
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND 12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
MS =MAINSTEM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM =TRIBUTARY MOUTH
SOURCE:EWT&A 1984 RIVER MILE 1,42 TO 144
tIr
1
l
/.
,I
I/.
I,
!
1
I
Ii
\'
I
]
}
J
]
}
1
;~
I
)
]
1
J
J
1
(J
FIGURE E.3.2.34
DELINEATION OF HABITAT AREAS IN THE MIDDLE SUSITNA RIVER
AT 23,000 CFS (TOP)AND 12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
MS -MAINSI EM
SC =SIDE CHANNEL
SS =SIDE SLOUGH
US =UPLAND SLOUGH
TM .-TRIBUT ARY MOUTH
SOURCE:EWT &A 1984 RIVER MILE 144 TO 146
tJ
'J
--J
)
)
1
r·l
I
.J
]
']
1
]--==========--j==-~~-...}
;I
)
l
I]
11
FIGURE E.3.2.35
AREAS IN THE MIDDLE SUSITNA RIVER
CFS (TOP)AND 12,500 CFS (BOTTOM)
LEGEND:
+=RIVER MILE
=MAINSTEM DELINEA TION OF HABITAT
SC =SIDE CHANNEL AT 23,000
SS =SIDE SLOUGH
US =UPLAND SLOUGH SOURCE:EWT &A 1984
TM =TRIBUTARY MOUTH
RIVER MILE 147.TO 149
Slough 9
Oxbow One
10.7%.
~Side Channel
10 oJ /7.9%
Twelve S iles
CO/Tl bined
SIDE
CHANNELS
Slough 22
Mainstem II ,
.9.3%,OibowOne
Eight Sites \'/8.2%
Combined 4.0.'%
Whiskers Creek
S 10 ugh
6'~UPLAND SLOUGHS
COMBINED'MACROHABITAT.
""TYPES
,Side Channel 10
.,SiDE S LOUGHS ~.
'F i ~~Tr:lbu.l.arle,«<"'".•
comblnedIO.4%-'·~
DENSITY DISTRlScUoTIQN "AND 'JUVENILE CHINOOK SALMON BY
MACROHABITATTYPE ON THE SUSITNA RIVER BETWEEN THE
CHULITNA RIVER CONFLUENCE AND DEVIL CANYON,MAY THROUGH
VEMBER 1983.PERCENTAGES ARE BASED ON MEAN CATCH PER CELL.
E:ADF &G 1984c FIGURE E.3.2.36
30.
JUVENILE CHINOOK SALMON MEAN CATCH PER
CELL AT TRIBUTARIES AND UPLAND SLOUGHS BY
SAMPLING PERIOD,MAY THROUGH NOVEMBER 1983
J
1
\
a'!!IZ
l3 TRIBUTARIES
!Za UPLAND SLOUGHS*NO EfFO~
n =CHINOOK CATCH
AUGUSTJUNE
I •IS
MAY
o.o+..;.r::=f-';';';
20.0
..J
..J
UI
c.J
a:
UI 10.0Q,.ftl ~.
:z::
c.J
I-<
c.J ---....-
2.0
Z
<U1.
~
"'11
1.0
S.O
....··......~·......·-I·._6.01_.-li@Ji~s~'~;~~~~D'T,oNs--~~~Ds~Tc:,.A~~~kITlONS*NO EFFORT
n •CHI.NOOK CATC H.
4.0
..J
..J.....
c.J
a:-~--3-.0,...-..--.......'-""'"....
··..·..--..··....----1-..:1:....-..
~
c.J
Z<.....2.0
~
1.0
...
1-
J
I
I
'j
I
JUVENILE CHINOOK SALMON MEAN CATCH PER
CELL AT SIDE SLOUGHS AND SIDE CHANNELS BY
SAMPLING PERIOD,MAY THROUGH NOVEMBER 1983
SOURCE~ADF &G 1984c FIGURE E.3.2.37
I
r
Mainatom II
Slough 20
Seven Mainstem
Situ Combined
Nina Sloughs
Combined
SI DE SLOUGH~
",
TRIBUTARI ES
MAl NSTEM SI DE
CHANNELS
Slough 5
,-
UPLAND SLOUGHS
'GOMBINED M~CROHA8IT~T
"TYPES
DENSITY DISTRIBUtiON OF JUVENILE SOCKEYE SALMON BY
MACRO HABITAT TYPE O,N THE SUSITNA RIVER BETWEEN THE
HULITNA RIVER CONFLUENCE'AND DEVIL CANYON,MAY THROUGH
OCTOBER 1983.PERCENTAGES ARE BASED ON MEAN CATCH PER CELL.
SO~RCE:ADF &G 1984c FIGURE E.3.2.38
Slough 19
4%
Mainsllm NO.2
9.8°/.
fourteen Mainstlm Side
Channe"Combined
O.~%Whiskers
Creek ~
Slough
I
,I
,/Eleven ~Ioughs
---Y Comblnmd
1.2%i
Ii c~a ..Icri uk ~TRIBUTARIESI~'<
!
WhiskersCrjek
Slough \
Whisker.
Creek
I
COMBINED MACROHABITAT
TYPES
FIGURE:E.3.2.39
SOURCE;ADF.&G 1984c
DENSITY DISTRIBUTldN OF JUVENILE COHO SALMON BY MACROHABIT AT
TYPE ON THE SUSITNABETWEEN THE CHULITNA RIVER CONFLUENCE AND
DEVIL CANYON,~4 Y TH,ROUGIji NOVEMBER 1983.PERCENTAGES
AREI ,ASED ON MEAN CATCH PER CELL.
I
--'~'-----...''~
SlouOh BA
Slvln SlouOhli .
Combined 2.5 %
5 louOh B 6.5%
SlouOh 9 7.B%
SlouOh II
MAINSTEM SIDE CHANNEL
UPLAND SLOUGHS
Eleven
Moinstem
Sites Combined
9.5%
100%
S louO h 6A
Whiskers Creek
S louQ h
Slough 22
34.l oio
COMBINED
MACROHAB'ITAT
TYPES.
TR 1aUTAR IES
SIDE SLOUGHS
Chau Creek
Four Tributaries
Combined 2.0%
FIGURE E.3.2.40ADF&G 1984c
NSITYDISTRIBUTION OF JUVENILE CHUM SALMON BY MACROHABIT AT
ON THE SUSITNA RIVER BETWEEN THE CHULITNA RIVER CONFLUENCE
DEVIL CANYON,MAY THROUGH OCTOBER 1983.PERCENTAGES ARE
BASED ON,MEAN CATCH PER CELL.
OCT.
FIGURE E.3.2.41
SEPT.
n=1,010
,.Tr.~rmTr.aTe a °
Ilnlx'II'r'
AUGUST SEPT.OCT.
.~··SidrSt·ouQhs .
~0-Upland Sloughs
~m-Side Channels
•-No Effort
o -No Catch
/.T r.-Trace
n",1,010
.•I···
-
AUGUST
-
JULY
I II
JUNEMAY
IIl lI I II III I I III
MAY .JUNE JULY
6.0-
5.0
1.0-
25
:I:
<..>.....«20
<..>
...J«.....
0 15.....
lL.
0
.....10
Zw
<..>a::w
0-S
JUVENILE SOCKEYE SALMON MEAN CATCH PER CELL AT THREE
MACROHABITATS BY SAMPLING PERIOD
MAY THROUGH OCTOBER 1983
PERCENTAGES OF THE TOTAL JUVENILE SOCKEYE
SALMON CATCH BY SAMPLING PERIOD,MAY THROUGH
OCTOBER 1983
SOURCE:ADF&G 1984c
"'5'.
'.,~U II TRllIUTARIES
IS.O ~UPLAND SLOUGHS
*NO EFI"ORT--------"--
10.0
••COHO CATCH
!j.0
,,'UI
...J
...J
lIJ S.Ou
a:7.0
lIJ
0..S.O
J:S.OU
I-4.0q:
U
Zq:
lIJ
:E 2.0
JUVENILE COHO SALMON MEAN CATCH PER CELL
AT TRIBUTARIES AND UPLAND SLOUGHS BY SAMPLING
PERIOD,MAY THROUGH NOVEMBER 1983.
'S.O
4.0
...J
...J
lIJ
(.)
a:3.0
lIJ
0..
'J:
(.)
I-q:
(.)2.0
z""
q:
lIJ::s
1.0
.'IIS
,';..
."J
!lei SIDE SLOUG H"
W HABITAT CONDITIONS
WZI SIDE CHANNEL
~HABITAT CONDITIONS'*NO EFFORT
il-COHO CATCH
JUVENILE COHO SALMON MEAN CATCH PER CELL
AT SIDE SLOUGHS AND SIDE CHANNELS BY SAMPLING
PERIOD,MAY THROUGH NOVEMBER 1983
SOURCE:ADF&G 1984c FIGURE'E.3.2.42
'l
1
1
j
,]
1
J
J
J
1
j
1
1
.1
j
1
"l
I
FIGURE E.3.2 .43
°-No Cotch
,E)-Side SlouQh.
~-Upland SlouQhs
II-Side Channel.
~-Tributori8S
•-No Effort
n =1,174
i a.sa.
~'.
-
,
.i ~v,,~
~reV;~-'"
,,9~..0:-.~.J..,j;ij';,EIt;;;:;U,VII-f-J'~I.,.:"-=.:",..,L.....L.rJ....:!I!'~....c::Ir-+...,...J.."::-:.Tr:Jo:...:1..'rLl'l-O...JlIIll::uY'il/+-'.;.;.:Tr.:.:::..O.:::..O,..,~.:::..O 0::..0:...;0::..,.....,..-.:0:.....,
r···.II rLn l I II'II III ,Ln'.!I:r.tc
MAY JUNE JULY AUGUST SEPT.
OCT.
50
~40
l-et
U
...J
~30o
l-
l.I.o
l-20
z
I.LJuex:
~I
O-'-f--.r.....r..;;.;,+-+---J....I-'"'"+--+-o...L...i~--r-=---...=;..,...-~---:-~-;-O"--....;0"-r
I I II I
OCT.
5.0
Zet
I.LJ
::\E 1.0
...J 4.0
...J
I.LJ
U
SOURCE:ADF&G 1984c
JUVENILE CHUM SALMON MEAN CATCH PER CELL
AT THE FOUR MACROHABIT A TS BY SAMPLING PERIOD,
MAY THROUGH OCTOBER 1983.
PERCENTAGES OF THE TOTAL JUVENILE CHUM
SALMON CATCH BY SAMPLINGPE:RIOD,MAY THROUGH
OCTOBER 1983 ..
M a ins t e m 0 i s e h a r 9 eat G ol'd.ere,e k
1,000
-en
Q)
I-
(J
CO-
CO
Q)
l-
e:(
Q)
0
CO-100''-
:::::len
50
5 10 15
MAINSTEM
20
(X10'!"'"3 efs)
SURFACE AREA RESPONSES TO MAINSTEM O'ISCHARGE
IN THE TALKEETNA-TO-DEVIL CANYON REACH OF THE
SUSITNA RIVER (RM 101 TO 149).
SOURCE:EWT &A 1985b FIGURE E.3.2.44
!
WETT~D ~REA OF SITE
@ I~ligher Flow
!,i
I !I
I ,i I
CLEAR WATER'i TURBID WATER
@ Higher Fl,ow @ Higher Flow
.',.
I
I I I
, I Indistinct Channel (Shoals)Side ,Sloughs !DIStinct Channel[I
lrlbutiIY Mouths Upland Sloughs i@ ,Higher Flow @ HIgher Flow
G 1 I
I .
Dewalered!
I
@)Lower Flo.w
i
Clear Waler I Tturbid Water Dewatered Clear WaleroLowerFlowi0,Lower Flow @ Lower Flow o Lower Flow
i I
I !I I I
I I I I I I I I I
With,Apparent .Without.Apparent Side Channel Malnstem Become Dlstlncl Remain Indlsllnct Wilh Apparent Without Apparent
Upwelling Upwelling (ltSllhan!10%Side Channels 4»Lower Flow Upwelling Upwelling
01 Flow!)I •Lower Flow
2 3 4 i I 10 5 6 1 8;,
!
I
i i
iii
FLOW CHART FOR CLASSIFYING THE TRANSFORMATION OF AQUATIC HABITAT!I '..
TYPES BETWEEN TWO FLOWS (CATEGORIES 0-10).
SOURCE:ADAPTED FROM EWT&A I ANI D WCC 1985;
EWT&AAND AEIDC 198~.
i
'l·i····
'-----'
FIGURE E.3.2.45
.4
1.0
.9
.8
x
W .7oz
.6
>-
I-
..J .5
CD
<!
I-
::::>.3
(J)
.2
.1
JUVENILE CHINOOK
SUITABILITY CRITERIA CURVE DEPTH
SUITABILITY CRITERIA
SUITABILITY
DEPTH INDEX
0.00 0.0
·0.14 0.0
0.15 1.0
10.00 1.0
o.
o 1.0 2.0
DEPT H (FT)
3.0 10.0
SOURCE:1984c
JUVENILE CHINOOK SALMON SUITABILITY CRITERIA FOR
·DEPTH APPLICABLE TO CLEAR AND TURBID WATER HABITATS
FIGURE E.3.2.46
SUITABILITY INDEX
Clear water less than 5 NTU
Turbid water 50 to 200NTL
Turbid
0.42
1.0
1.0
1.0
0.80
0.60
0.38
0.25
0.15
0.07
0.02
0.01
0.0
0.42
1.0
1.0
1.0
1.0
1.0
0.68
0.44
0.25
0.18
0.12
0.06
0.0
Clear
LEGEND
---TURBID
CLEAR
Velocity
0.0
0.05
0.20
0.35
0.50
0.65
0.80
1.10
1.40
1.70
2.00
2.30
2.60
\
\
\
\
\
\
\
\
\
\
\,,
,1,,'II,!,,
'......'............,
1.0
0.8
x
W 0.6
0
Z-
>-
I--
:::!0.4m
?=(
I--:0en:
0.2
3.02.51.0 1.5 2.0
VELOCITY f'.p.s.
0.5
00 I I --:>., I I I I I·I
o
~UVENILE CHINOOK SALMON SUITABILITY CRITERIA FOR
VELOCITIY ·APPLICABL~TO CLEAR AND TURBID WATER HABITATS.
!.
SOURCE:ADF&G 19840;EWTfA!and WCC 1985
FIGURE E.3.2.47
-'--'------'
LEGEND
-CLEAR
_-TURBID
Percent Cover
·0.1 0 - 5
0.2 6 -25
0.3 26 -50
0.4 51-75
0.5 76-100
,.....
I r
s
L-
III
M
r--
,.....J
I-1J111111111~
U IIIII1
~
Jl
'-
----1.....0.50.1 ..050.1 p 0.5 0.1 ...0.50.1 ...0.50.1 "---.050.1 ·0.5
No Cover
2
Emel1lent
Velletation
3
Aquatic
Velletation
4
Oebris and
Oeddfall
5
OvertJallllinll
Riparian
6
Undercut
Bonka
7
Larlle
Gravel
8
Rubble
311
-5 11
9
Cobble or
Boulders
over 5"
PERCENT ·COVER by COVER TYPE
COVER SUITABILITY CRITERIA RECOMMENDED FOR USE IN MODELING JUVENILE
CHINOOK HABITAT UNDER CLEAR AND TURBID WATER CONDITION.
FIGURE E.3.2.48
....lJlIJHLE:EWT&A and WCC 1985;EWT&A and AEIDC 1985
'--~
·1
o if!e I :.I .I .'I I I I I 1o!1.0 I '2.0 3.0:4.0 5.0 6.0 7.0 8.0
DE PTH (FT)
I
.I .D,EPTH SUITABILITY CURVE FOR CHUM SALMON SPAWNING.
I
FIGURE E.3.2.49
SOURCE:ADF&G 1984b .
~::::::-----
1.0
1.0
0.2
0.0
VELOCITY
0.0
1.3
2.8
4.5
SUITABILITY CRITERIA
SUITABILITY
INDEX
1.0 2.0 3.0'4.0 5.0
VELOCITY (FT/SEC)
VELOCITY SUITABILITY CURVE FOR CHUM SALMON SPAWNING.
SOURCE ADF&G 1984b FIGURE E.3.2.S0
SUITABILITY CRITERIA
SUITABILITY
CODE INDEX
1.0 0.00
1.1 0.00
2.0 0.00
2.1 0.00
3.0 0.00
3.1 0.025
4.0 0.00
4.1 0.05
5.0 0.00
5.1 0.20
6.0 0.00
6.1 0.60
7.0 0.00
7.1 1.00
8.0 0.00
8.1 1.00
9.0 0.00
9.1 1.00
10.0 0.00
10.1 0.85
11.0 0.00
11.1 0.70
12.0 0.00
12.1 0.25
13.0 0.00
13.1 0.00
I
!
: t .COM~UNED SUBSTRAtTE;/UPWELlING SU,TABILITY CURVE FOR CHUM SALMON SPAWNING.
1.0
.9
.8
X
w .7
0z
.6
>-
I-.5--J-CO .4«
I--.3:::>
C/)
.2
.1
0
SOURCE:ADF &G 1984b fIGURE E.3.2.S1
REPRESENT ATIVE GROUP I
SITE ·107.6L SITE 112.5L
1 """500
(SLOUGH 5)500 (SLOUGH 6A)
...:"""---e-e-en 400 400en
0 00
0 0
0....300 ....300......
(J)(J)c.c.
...:200 ...:200--
0'e-
en 100
en 100'-''-'
<<
::>::>
~0 ~0
0 10 20 30 40 0 10 20 30 40
(THOUSANDS)(THOUSANDS)
MAINSTEM DISCHARGE (01s)MAINSTEM DISCHARGE (01s)
REPRESENTATIVE GROUP II
SITE 101.4L .SITE 113.7R
"""500 (SLOUGH 38)500
(SLOUGH 8)
...:'"""l---e-e-
en 400 en 400
0 0
0 0
0 0....300 ....300......
(J)(J)
c.c.
...:200 ...:200--e-O'.
en 100 en 100'-''-':.',1
<<
::>::>
~0 ~0
0 10 20 30 40 0 10 .20 30 40
(THOUSANDS)(THOUSANDS)
MAINSTEM DISCHARGE (01s)MAINSTEM PISCHARGE (01s)
SITE 126.0R SITE 144.4L
(SLOUGH 8A).500 (SLOUGH 22)
"""500 """-....:--
d-d-400en400en
0 0
0 0
0 0 300....300
....
......
(J)(J)
c..~.c:l.
...:200 ...:200--
d-e-
en en 100'-'100 '-'
<<
::>::>
~~00
0 10 20 30 40 0 10 20 30 40
(THaIIS A.NDS)(THOUSANDS)
MAINSTEM DISCHARGE (01s)MAINSTEM DISCHARGE (01s)
JUVENILE CHINOOK HABIT AT QUALITY RESPONSES
TO MAINSTEM DISCHARGE FOR MODELLED SITES
IN THE MIDDLE SUSITNA RIVER PAGE 1 OF 4
FIGURE E.3.2.52
]
1
l
J'1
)
1
,i;-:i
I
:'J
l
1
!J
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
o -!----...----.---.__.-..-.._-._...._.;.,._.;.,..._.""T__-••.;.,._.-_.r-~-.__--.._.""'-"""'-"'""""'=_=_,.1...__'·'--0---·
""1 500...-
C"rn 400
0
0
0,...
300...
Q)
Co
...:200-
C"rn 100.....
<:::)
3:0
0
SITE 128.8R
(SLOUGH 9)
...
Q)
Co
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
200--
SITE 141.4R
(SIDE CHANNEL 21)......5 00 -r------=-:;..~:.....::...:..:.....~-:.-:......:::....;..:...-____....-
e-
~100
<:::)
3:
~400
···-0··----
oo,...300
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (0.1.s)
o +----.,..I.--.....---.,.----.--.....--r----r~
o
SITE 132.6L
(SIDE CHAN.NEL 10A)
PAGE 2 OF 4
FIGURE E.3.2.52
REPRESENT ATIVE GROUP III
JUVENILE CHINOOK HABITATQUALITY RESPONSES
.TO'MAINSTEM OI$CHARGE .FOR MODEi.LED SITES
IN THE MIDDLE SUSITNA RIVER
~400
ooo,...300...
Q)
Co
...200-
SITE 101.2R
(WHISKER'S CREEK EAST SIDE CHANNEL)......500...-
<:::)
-3:--·-·0-+----,.-I---.--'"T--....---.---r--.....--r--~
····~-··o-···~··ro···---·ZO-:-·····30-··-~-40··-.
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
500.........-e-400rn
_....+._~"~_.._._.__._..-
0
0
0 300,......
Q)
Co...200-e-rn 100.....
REPRESENTATIVE GROUP IV
SITE 112.6L
~1 500 ...--.:...:(S~I.=.D.=.E_C::..:H...:.;A...:.;N...:.;N..:..:E::.:L:::-..:6..:..:A;.;.J ---.
l+l,!
,....,500--
SITE 131.7L
(4th OF JULY CREEK SIDE CHANNEL)
cr
UJ,·-\,400o
"Ic)
....··300...
Q)'l
C,i
.:1200'to._.J
cr
-;rr 100
j,
...J"'-
3:
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
g 400
ooo,...300...
Q)
c-
..:200-
cr
~100
<:::>
3:
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
300
400
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
. 0 +---,r---,...-.....,--....--..,.--r---r-----.r--~o
100
200
SITE 136.0L
500 ..,-...:.:(D=-.=...:::OU..:::G:....·.:::.S-.:D::..:E:::.:L:::.:I..:::G:..:.H.:...:T~S..:.:I D::..:E:::.....;C:::,H..:.:A..:.:N.:.:N..:.:E=.,:L::.::J----..
SITE 134.9R
(LOWER SIDE CHANNEL II),....,500 -r---=~::":";"~=-==--="':"~':';":':::"::;"":":':"'---,.,'-,\.~I
I I
2?'400
o
Cl'\Sa 300
,LJ
Q)
c-
.{!200
~I
6·J
~100
<.'§J
JUVENILE CHINOOK HABITAT QUALITY RESPONSES
TO MAINSTEM DISCHARGE FOR MODELLED SITES
IN THE MIDDLE SUSITNA RIVER
PAGE 3 OF 4
FIGURE E.3.2.52
REPRESENTATIVE GROUP V REPRESENTATIVE GROUP VI
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
SITE 133.8L
(SI.,OUGH 10 SIDE CHANNEL)
'""500--c-400III
0
0
0....300...
Q)
a.
...:200-
0'
III 100.....
~:::>
~0
010203040
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
O+----,--r--.,...----,---r--.,...---r--r---f
o
200
...
Q)a.
SITE 141.6R
500,...-...::.(.::.S.::.L.::.O-=U-=G:..:..H:.....=.2...:.;O:....-----,
c-400
III
oo
~300
--
.~,I
l,1
,j
J
.J
Il
[
,j
,'J
,,\
II
I
40
PAGE 4 OF 4,
FIGURE E.3.2.52
10
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
O+----,--r--.,...---r--r--.,...---r---r-~
o
g 400
ooo....300
REPRESENT A TIVE GROUP VII f.~~.
SITE 119.2R \"]
(LITTLE ROCK SIDE CHANNEL)'""500 -r---=----=-..::-....:..::....:....:...:.-=...:-=-=--=.::..:..:...:..~.::..::.::...---..--
go 400
oo
~300
...
Q)a.
_200-
0'
~100
~
:::>
~
O'..c.,..
~100
~
:::>
~
...
Q)
a.
~..:;:·200-
40
JUVENilE CHINOOK HABITAT QUALITY RESPONSES
TO MAIN STEM DisCHARGE.FOR MODEllED SITES
IN THE MIDDLE SUSITNA RIVER
10 20 30
(THOUSANDS).
MAINSTEM DISCHARGE (01s)
10 20 30 40
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
O+----,--r--.,...----,---r--.,...---r--r---f
o
REPRESENTATIVE GROUP VI
SITE 136.3R
200
c-400III
0
0
0....300...
Q)
a.
...:200-c-
III 100'-'
~
:::>
~0
0
...
Q)
a.
go 400
oo
~300
--
'""500.,.----------------,--
0'
...~_100
~:::>
~
20 30
(THOUSANDS)
MAINSTEM DISCHARGE (01s)
REPRESENTATIVE GROUP IX
SITE 101.5L SITE 147.1L
(WHISKER'S CREEK WEST SIDE CHANNEL)(FAT CANOE ISLAND)~..':500---··~-·--···-..--~--.-..---.,--...500
~--·=---I---··---_··__·_···_~·_····-I--.~·---I-----·_·-··---··------··~---I
......--
SITE 101.7L
(UPPER WHISKER'S CREEK SIDE CHANNEL)50'"",--~,;",;;,;,;",;;,;;,;,;,;;,=,;,;;",;~=,;~;,,-,---=~-,
SITE 105.8L=50-r-------------------.
3612162024 28 32
(THOUSANDS)
MAINSTEM DISCHARGE (ets)
8
C'
CIl.....
36121620242832
(THOUSANDS)
MAINSTEM DISCHARGE (ets)
8
10
.0 +..,......,....'-r-..,....-r-...,.......,.....,...__-...-......,....,....,.~
4
C'
CIl.....
,....--
tT
CIl.....
SITE 114.1R
(LONE CREEK SPAWNING SITE)
50-.------------------.,....--
SITE 115.0R
(MAINSTEM II )30..,.------..:.:.:=;.:.;...=..;.;..:.-------,
40
10-
36812 16 20 24 28 32
(THOUSANDS)
MAINSTEM DISCHARGE (ets)
<,....Wooa:o<z 30
w<...Joo
1Il::::>
<0 20
00 I::::>1-.....o
W
l-
I,52
W::36812162024'28 32
(THOUSANDS)
MAINSTEM DISCHARGE (cts)
4
-.::-SITE 118.9L
(LOWER LITTLE ROCK SPAWNING SITE)50 .,.---.::.,;;;;;.;.;..;:.;,;;..::.:..;..;.:::..=...;;;.,:;.;;.;.;.;:;.;.;;;.;.=.;.;;..;;;.:.:.;;:.:.-----,,....--SITE 119.1L50,.....--------------_---.
40-
8 12 16 20 24 28 32 sa
(THOUSANDS)
MAINSTEM DISCHARGE (e1s)
4
10
tT
fIl.....
<w,....a:00<~30
w<...Joo
1Il::::>
<0 20
00 I
::::>1-.....o
W
'l-
I
"W::e 12 16 20 24 2.8 32 36
(THOUSANDS)
MAINSTEM DISCHARGE (ets)
tT
CIl.....
TOTAL HABITAT AREA RESPONSE CURVES
IN CHUM SPAWNING SITES USING
IFG AND DIHAB MO D ELS FIGURE E.3.2.53
PAGE 1 OF 4
-.50--
C'
'"......40<w .....a:C/)
<0 30 _Z
w<...JC/)
m:::::>
<0 20
C/)J:
:::::>t-
0 .10Wt-
J:
"0w 4 8s:
SITE 125.2R
(SIDE CHANNEL 8A
12 16 20 24 28 32
(THOUSANDS)
MAINSTEM DISCHARGE (efs)
SITE 128.81:'
,...,
50--
C"en....
<40
w,...a:C/)
<0 30Z
w<...JC/)
m:::::>
<0 20C/)J:
:::::>t-....
0 10Wt-
J:
"W 0
36 s:4 8 12 16 20 24 28 32
(THOUSANDS)
MAINSTEM DISCHARGE (efs)
36 ,I
I
FIGURE E.3.2.53
PAGE 2 OF 4
TOTAL HABITAT AREA RESPONSE CURVES
IN CHUM SPAWNING SITES USING
IFG AND DIHAB MODELS
SITE 133.8L
~(SIDECHANNEL.l0)'=50-50 --~_..---~t:r-_."..._-~._--,--------
tTen
----"-"~-~-en....
<40 40-
W,....<,...
a:C/)WC/)
<0 a:o
w Z 30 <z 30
...J<w<
mC/)...JC/)
m:::::><:::;,20 <0 20C/)O
:::;,J:C/)J:
t-:::::>t-
0 ........
0W10W 10t-t-J:J:""w 0 w 0s:4 8 12 16 20 24 28 32 36 s:4 8
(THOUSANDS)
MAINSTEM DISCHARGE (efs)
,...
50--
t:ren....
~40 -
w,....a:C/)
<0 30 •Zw<...JC/)
m:::::>
<0 20
C/)J:
:::::>t-
0 ....
10 -Wt-
J:
-~-f:2-o --~
ws:4 8
SITE 131.3L
'14th Of JULY SIDE CHANNELl
'=50-
tTen....
40 -<,...WC/)
a:O
<z 30
W<...JC/)
m:::::>
<0 20-C/)J:
:::::>t-....
0 10 -Wt-J:
..~------CL
W 0
12 16 20 24 28 32 36 s:4 8
(THOUSANDS)
MAINSTEM DISCHARGE (efs)
SITE 133.7R
.
12 16 20 24 28 32
,.(THOUSANDS)
MAINSTEM DISCHARGE (efs)
SITE 133.8R
12 16 20 24 28 32
(THOUSANDS)
MAINSTEM DISCHARGE (efs)
~
}
36 )
,I
,}
1
I
i
3.6
)
1
I
'"'50
C'en
'-'40<w'"'a:.U)<~30
w<...JU)
Qj::J
<0 20U)J:
::JI-
'-'
0 10W
I-
J:
Cl
w 8:::
SITE 134.9R
LOWER SIDE CHANNEL 11)
12 16 20 24 28 32
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
SITE 136.3R
'"'UPPER SlOE CHANNEL 11-50-
C-
eil...,
<40
w,....
erU)
<0 30Z
w<...JC/)
m::J
<0 20C/)J:
::JI-...,
0 10wI-
J:
Cl
w 0
36 ::4 !3 12 16 20 24 28 32 36
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
,....-50-0'
(,I)...,
<40-
w,....
erC/)
<0z 30-
W<...JU)
m::J
<0 20-U)J:
::JI-
0""
W 10-
I-
J:
Cl
w 0:::4 8
SITE 137.5R
,.....50--
0'
(,I)...,
AO-<,....Wc/)
ero
<z 30_
w<...JU)
m::J
<0 20 -.C/)J:
:::>1-...,
0 10wI-
J:
Cl
w 0
12 16 20 24 28 32 36 ::4 8
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
SITE 138.7L
---
12 16 20 24 28 32 36
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
SITE 139.0L SITE 141.4R'=50 '=50--0'0'(,I)(,I)'-'...,
<40 <AO
w,....w,.....a:.c/)erU)
<0 <0 30wz30-Z
...J<W<
mC/)...Jc/)
<::J m::J
c/)O 20-<0 20C/)J:::JJ:::JI-I-
0""...,
0w10-W.10l-I-J:J:Cl Cl
W 0 W 0:::4 8 12 16 20 24 28 32 36 ::4 8 12 16 20 24 28 32 SO
(THOUSANDS)(THOUSANDS)
MAINSTEM DISCHARGE (cfs)MAINSTEM DISCHARGE (cfs)
TOT AL HABITAT AREA RESPONSE CURVES
IN CHUM SPAWNING SITES USING
IFG AND DIHAB MODELS
FIGURE E.3.2.53
PAGE 3 OF 4
.]
.,
I .J
I )
J
I
l
>1
'I
I
1
1
1
36~~4·c~=_·B,_.1216,-2.0 =240..2832
(THOUSANDS)
MAINSTEM DISCHARGE (cfs)
40
2 so -r-----~~~'-I------
C"
(I)....
TOTAL HABITAT AREA RESPONSE CURVES
IN CHUM SPAWNING SITES USING
IFGAND DIHAB MODELS
OURCE:ADE'&G 1984b EWT&A 1985c
FIGURE E.3.2.53
PAGE 4 OF 4
J
.j
, j
I I
1
)
SITE 101.7L SITE 115.0R
150 (WHISICIlI's WIST SC)(MAlIlSTl!MII SC)
150
'"140 140..130 '":i ..lao
120 i0110
110
~~liD
:l 100 100..90 I 90
i 10 c 10
70 III
III
II:70
oJ 10 c
"III 10
50 iii!40 ;50..40=30 ..
:II:zo Ii:!aD
!!:II:20
~10 ;10
0
0 10 ~1IlS)aD 40 0
0 10 (~0USAHD8~30
40
1ilA11IITl!M DISCHARllI:(CI'!I)IIWN5T1M DISCIWIG (CI'S)
SITE 125.2R SITE 126.0R
ISO 1110
(SLOUGH SA)
t:140 t:140
i ISO Z ISO
§110 0 110
110 ~.liD
:i 100 !100..10 90
S 80 =80
c 70 II:
~c 70
"80 Of 80oJ..50 ..50
::;)c..40 !40III
!C SO a so
'"10 !Ciii zo
ilII 10 !!
III 10
0 !!l
0
O·10 20 so 40 10 20 aD 40
(THOUSAHllS)(nIouSAHOS)
NAIHSTl!M DISCHARGe:(CI'S)IIAIfI5T1M DISCHARGe:(CPS)
HABITAT QUAUTY (WUA/1000 SQ.FT.)RESPONSE
OF CH.UM SPAWNING AREAS (MODELLED SITES)
FIGURE E.3.2.54 Page 1 of 2
,-1
SITE 133.7R SITE 134.9R j
ISO ISO (LOWERSCII)
~140 140..130 ~
i ..110
120 Ii..litO..110 §110g
:I 100 100..90·I eo
i 80.c eo
:r70...
II:70IIIC
oJ 60 ...80,...!lO I SO::;)40co 40r:30 ..10 ]:I:~!!20 :I:20
I 10 !l!---;I 10
0 0010~1lDS)30 40 0 10 (~OUSAHDlI~10
40
J
IillAIHlITI!IiI DISCH_(CPlJ)IlIAINSTI!IiI DISCIlAIlG (CI'S)
I.1
,I
SITE 137.5L SITE 141.4R
-1ISOISO(SC21)
t 140 t 140
0 110 i 110
j..litO8 ..180
110 ..110!2 2
II:100 ~100...·...-80-ItO-
t SO ~80 l70II:
~
c 70
eo III 80!!oJ
SO •OJ c 1IO
::;)..co 40 ::;)40 '1..lIO aIe 10
!!!20 Ie 20..!!!ill 10 ...10
0
ill
0
0 10 20 10 40 20 lIO 40
(THOIIlIAHDS)(THOUSANDS)
.._.,-~-~-._.--.,--,-----...-.•.---·-MAINSTl!lil-DISCNARGE,(CPS)-------·-·'MAllftITl!IIl-DISCHARGE-(CPS)'
HABITAT QUALITY (WUA/1000 SQg FTg)RESPONSE
OF CHUM SPAWNING AREAS (MODELLED SITES)
FIGURE E.3.2.54 Page 2 of 2
I
j
)
)
]
-'"l--
Li-.......
BREACHING FLOW
SHIFT
~---~:>t
I I
I I
I I
I I
I I
I ,
I I
WEIGHTED USABLE AREAl _...._--~"::\
I
c l <\<~I :=ll<,
....I:::!I \=.5 ..._..._J~
~':!~I=\
"".:'"•CISl~S 1~"L::il~/::l~21=g I~
:::,/~I'""
I il
I I
I I
MAINSTEM Q (CFS)
Lateral shift of weighted usable area (WUA)curve of a modeled
specific area to synthesize the mJA curve of a nonmodeled specific
area that has a different breaching flow,
----MODELED SPECIFIC AREA
~~~NOH-MODELED SPECIFIC AREA
'..........
STRUCTURAL HABITAT
QUALITY ADJUSTMENT
___~r--__"
\
\...----------...,\
"-",\
'\\
\\
\\
\~,\
"~',~
,,~
SOURCE:EWT&A and AEIDC 1985 MAINSTEM Q (CFS)
Ad]ustment Of the we1g11t""ed""usabl-e at ea -('HUA)Cttrve--e£a meaeled.
specific area being used to synthesize the WUA curve of a non-
modeled specific area to account for'differences in structural
habitat quality between the two specific areas.FIGURE E.3.2.55
j
1
1
j
_0
1
j
I
1
}
I
j
I
l
1
l
1
1
36
36
32
32121620 24 28
o (THOUSANDS)
MAINSTEM DISCHARGE(cfs)
8
REPRESENTATIVE GROUP 6
REPRESENTATIVE GROUP 4
REPRESENTATIVE GROUP 2
O+-~,......,,......,__r....,._...__.__.__.__r__r__.,.__,......,,.......j
4 8 12 16 (THOt?SANJS~28
MAINSTEM,DISCHARGE (cis)
5..-~---------------,
5...------------------,
5,---------'"-------,
.!4
36
12 16 20 24 28 32 36
(THOUSANDS)
MAINSTEM DISCHARGE(cfa)
8
PAGE 1 of 2
FIGURE E.3.2.56
CUMULA TIVE JUVENILE CHINOOK HABITAT
AREA RESPONSE TO MAINSTEM DISCHARGE
IN EACH REPRESENTATIVE GROUP.
8 12 16 20 24 28 32 36
-(-THOUSANDS)0
MAINSTEM DISCHARGE(cfs)
8
REPRESENTATIVE GROUP 3
REPRESENTATIVE GROUP 5
REPRESENTATIVE GROUP 1
5....----------------.
o+=;::::;=;:::::::;::::;::::::;:::::::;::=:;:::::;=;:::::::;::::;::::::;:::::::;::=~
4
4
5-r----------------,
5..,....------'"------------.
--t7
~
REPRESENTATIVE GROUP 7 REPRESENTATIVE GROUP 8
5 5
...a ....:..4 ,;..4
<t ..:!.w_~""en
:~3 ...-<ten 3....-w Z
Illl ....al~<t=en==<t-
::::1-2 en==2::::I-ew e..w:z:..Cl :z:w·Cl~W -3=---0 32 36 04 8 12 16 20 24 28 4 8 12 16 20 24 28 32 36
(THOUSANDS)(THOUSANDS)
MAINSTEM DISCHARGE (ch)MAINSTEM DISCHARGE (ds)
REPRESENTATIVE GROUP 9
-..:-,;.
~
5-r----------------,
4
<t_wen
~~3
w::::i........etl-
<t==~-2
ew..:z:
!:2w
3=---------------o ~~--,...........,.._.__r__r__,.....,r__r__r___,......,._..,......f
4 8 12 16 20 24 28 32 36
(THOUSANDS)
MAINSTEM DISCHARGE (ch)
CUMULATIVE JUVENILE CHINOOK HABITAT
AREA RESPONSE TO MAINSTEM DISCHARGE
IN EACH REPRESENTATIVE GROUP.
PAGE 2 of 2
FIGURE E.3.2.56
3 I".,",,"i i ,-d I
q
5D
to Flow
COMbined
qD2P3D
t"'iAIN~TEt"'i [tISCHAFtGE
(CFS H mDD)
InIl
5
I
'1 i I
I I'I
il 'A~I .••~I '.
Ei-l''. '. '.'.', I . . ' . .,"".". ".".".
I I"."......-:::::-........ .... .... ........'..~r
f
\0.'.--...-''.'. '.'..'.'\
I ··.1.··.1.:····.::··:::···::::··:::,··:::<::::::::::.::::::"::::::.::::::::::::'''::::::::>\
~t.I I
E M
I
&M
Ii I
T l
E l
D I
D
U M
5 5
A
E:D
l F
E
5
A n.R
E F
A T
Ii
II I
FiglllrNe Ett3tt2J~?:,
"fte:5Pon:5~1 o:f Re~~ing Habitat
In All ~EtP~esen~ativeG~olIlPs
.---''J _f _.___'~------'.~
,t.I I SitD
N
M liltS -
I
l
l lIltD -
1 I
D
N "1:5.J:t -
5
D ~:D.....:t -
F
5 2:t5 ~.Q
F atD
.~T D
f;,,\,~~'-
.'I ..............'..../\I ~.
•••••••••••••••0°0°•
I·~1 r I
10 em 3D tiD 5D
MAfN5TEM £l15EHAfUrE (EF5 ~mDD)
Figilltre Ett3tt2tt5B:
Response I[)£Re.E\Jt:&ing Habitat Area to
Flow in RepJt1tesent~lttive GrOIlJlPS 2jt 3jt 4:
~t~I 10£1Eltl
I T tiD&
H H SD
T £I
E U 1£1
0 5 6£1H
U ltl 5£15[~
H 5 4£1
E~
l ,£I 3D
E F 2£1
H 5 10Rq
E £IHF £I:T
~
I
.--....iJ..''":'--."i.1 .0'.0-.0.j
I .'...'':1-:
/
t-
o ..0°0°..!9'-.-.-:
i .."0°.."....":.,,"~--.-...-..-.-.
1 .0',0-,0°.0 'r .."0°--:_.J ,~.0"0°~
I,I·. ..'"1'. . . ..' .'. . . ...,I,.'.....'..'..,..'..'..'..'....'..'..'..'..'".,.
i i.'..'..'..'..'..'..'..'..'."..'..'..'..'."'..
1 ••••••"1 ...i \
J/" '..,
I )'~
Ii'.. .. .. ..•.. .. .. ...'• •.. ........•....
/
.1]::::::::::'::::::::::.::>::::::::::::::::::::;:::.::::::::::::::::::::::::::::::::::::::::::::::::.::::::::::::::::::::>::::::::::::::::::::::::':::::>::
.."i.......... ..'...'...... .. ..."........ ....j~··..i.··..l'·..·.·..······;.············..
i I I i
I 1£1 Hi 2£1 25 3D 35
t~1H ltl5TEtt1 [~15CHflR&E (CF5 ~-~10£1£1),-.,
Respon$e of ChUDl Spawning
Alc-ea tlo Flow in IFG and
DIHAB i llodel Sites
Figul"t.e E~3~2~59
-.;.
'-'----~------'~~--''-'--'~
~~I
ltD
E N Dtq -
I
G t..1 Dta-
H I
T L .Dt1-
E L DtS·D I .
~)DtS·~I ~Dttt -
A
B 0 Dt3 -
,L F Dt2 -E
0.:'"Dtl--'A (~
R DtDEF DAT
~4::::"'::::::':::::::)>-
.l""".'".'.'"........
.JO"/<%:::'::'::::'::::::::'::::::'::::::::::::::::::::'::::::~~,
. .//..:./::.:::::::/:::::.::::::::::::::::::::::::::::::::.:::::::'?:;
I I I I
10 2D 3D ttD 5D
t"1AINSTE~1 DISCHARGE (CFS K mDD)
Response o£ChUM Spawning
AJittea to Flow in
RePJittesenta tive Grollltp :2
Figllltl:&e Ett3tt:2tt6Q
I
fTlj",.I."--:r--"""-.j • • •.·i ..'•.....'..'..'..'..'..-,...
••' i ••'••'.'••'••'.'.·i .'..'..
"')..1 ···..··1.···..'......:-r-.7.::i ..J./c.::..<>:::::::::>:::..:::::.::::::..:::::::::::::..'..'""'....--~'-.--
sn~O 3D blO
INSTEt"1 DISICHAFt1::rE (CFS H moo)
i
Responke ot ChUM Spawning
Area to Flow in .
Repres~ntative Grollllp 3
Figllllre E1t31t21t61.
10
~u..I I ltD
E N ntli
I
Go tu-i ntS
H I
T L
nt1
E L ntSDI
0 ntSuN.-S ntbl.:::.
A
B 0 nt3
L F
E nt~
-:'"-"ntlA(~
R ntO
E F 0AT
--~-------"---~-----------'-------""~'--.-'~''-----""'
~~II
ltD
E N DtClI
G t--i DtH
H I
T L Dt1
E L Dtb0I
0 DtSUI~S Dt4
A
B 0 Dt3
L F Ot&!E
S Ot IAQ.
R OtO
E F DAT
....~,....~-~
•t·---:..·---:·,.........'........').."j.:..:::::::..::..:>:::..::....>::,.,
./../:::.,..://../.././.~/:./::/.>:./::...::./:/./...:...<~
:::::::::::::::::::::::::':::::::.::::::::::::.:::::,:::.::::::::::::::::::::::::.::::?>~~
.".,
m &!D 3D 4D SD
~1AlNSTEt"i DlSCHAFtG..E (CFS H mDD)
Response o£ChUM Spawning
A:rttea to Flow in
Rep:rttesentative G~Olllp 4:
Figlll:rtte Ett3tt2tt62
iaD 30 4D 50
AtN:5TEtw-1 [):5CHARGE (CF:5 H mOD)
Respo~se at.ChuM Spawning
Area to Flow in
Representative GrOIlJlpS 2,1t3,lt4
FigllJlre Ett3tt2tt63
,
tI I,'I I"'--~..'.'
~..J t ItO
E N Otlit
G tw-1 OtH
H t
T L Ot1
E L Otli[)I
0 OtSUN
-:.:::5 Ot4....
A
8 0 Ot3
L F
E Otia
:5 OtlA~
R OtO '
E F 0AT
~--'------'----'--~---'-------------------..:---;------"~---'------
~r1:11:...
EL.E lot.tt
qO%
50~{
40383634323DiaBasa4
, , .f'1""'""""...,'".",)1 -.,..,'
,,'.,'.~......'~.".........._,'
r"",.,'
\'".'
\1~
ia2
3 I too ""~'"~''""r"" " ,~,"",~~"~''"~"I
4
5
6
1 ~'""""'"",,,'",""",I
-CifLE(It[IAR NEE~:5
'E1I:31l:211:64 :E:E[H(ltllU(lt&Mif\t al
Chinook Realt."t..ing Habitat Alt."t..ea
Undelt."t..Hatult."t..al Flow Reginle
In All Replt."t..e:s:enta tive Glt."t..oups:
NI
E (It
I
[f M
H I
T L
E L
D I
0
U (It
5 5
if
E:0
L F
E
5
if Q.
R
E F
if T
..19U1t."t..e
Ei ""r',,""1""1"'"",,"",,"",,"""""1'"to,,,,",,'',,'",,""""",,"""W "..w",""""""'''''~
~rt:1t•••CU .."tt
10%
~rt:It•••~L.E.·tt
liD38:£s'I 3D :£2 :£li
!CALEM[lAR ~t.fEEI{5
~IE&IMMIM&MA\t 21
28
I
1
t !~----:!-.......--.-.-.-_.~.;~_.....••_....lot.-.t.-_lot.-La.
~~..····'1..-:-_-.,:."-.......••••••••~-••~-........I..to l.~...to ••_..~~~-r'-•••-------:.r:--••~.~~~~.~/~~-~--~~~~
.. ...... ..to ..to....••..to ......"I ."!lot..t I.E I.E t ...t·.",s,,-?~... .. ......
li .0;l.tO i .._..bE tlo'.t lot ....•••..I......to .SO ........ ..I ."lot lot ..lot.."
.''..lot..·.1 "1 ..".to ...--....,~..fa ""~...".~..'r................................~-~~..····I ..
I.'.'.'.'.'•.':,ii.I '<'/.v--.'......••-I "1 ..to 'J4 .."
--......to .".....7 \.'~~~~~~~...............,'l'i'.'r;'lot....I••-I to
......•.....~I ~..........l....I•• I I.'•••~··IIf.I••'I.'•••I
.112i''"''''I i 1""r '.r":'"I ',,'I '''''"r '"""'I'"",,",r ' ',"'I
22 2li I I 2Ei
!
i
5
:::
i 1
Ett3tt8tt 6~:I
I ~hinook I Real.'"t.ing Habitat Al.'"t.ea
\Und~l.'"t.:tIatItJl.'"t.a~Flow Reg-iDle
I ~Jl Repl.'"t.~:sentatlve Gl.'"t.oup:s ;2;3;tltJ:
I f
I
"
NI
E M
I
&M
H I
T L
E L
tJ I
D
U M
5 5
A
~D
L F'
E
5
A Q.
R
E F'
A T
Figul."t.e
~---~--~--_.._-.-'---''--~._--''---------~------~--~-------
SALMON PASSAGE CRITERIA THRESHOLDS
1.3
1.2
1.0
FIGURE E.3.2,66
LINE B
COORDINATES·
-L -l-
o 0.20
200 0.25
160
LINE A
COORDINATES·
-L ...L
o 0.32
200 0.37
--PASSAGE CRITERIA THRESHOLDS
(1984 DATA)'~I.I
60 80 1 00 120 1 40
PASSAGE REACH LENGTH (FEET)
40
SUCCESSFUL PASSAGE WITH DIFFICULTY AND EXPOSURE
SUCCESSFUL PASSAGE
UNSUCCESSFUL PASSAGE
20
B
-0.9 Gj
W
0.\8~
:c
0.7 h:
W
0.6 0
~
lA .~0.5 ~
0.4~
I-
0.3
0.2
~0.1
1 1 1 1 I I 1 1 1 1 1 1 1 1 1 1 I 1 1 ~O.O
180 200
1.0
0.9
0.8
-0.7I-w
W
l.J...0.6
"-'
:c
l-n.0.5w
0
WD.4
~<t
(/)
~Oo3
n.
0.2
0.1
0.0
I'
0
SOUR¢E:ADAPTED FROM AD.F&G 19851
r.l rt:tt,.••
tLE.·1t
5D%
~rt:11:•••EEa.E ••tI:
35 i 3S 31 3B 3tI
CALENDAltt ~uJEEHS
8EG~NNING ,AUGUST 4
CIlllllM i Spawning Area in
.IFG Btnd DIHAB Model Sites
Unde~Natllllral Flow RegiMe
Figllllre EII:3II:211:b ?
32
3D
2D
m
[I -iI .i :.,•,,I
i
,
mD41 I I
tiD -I !I
I
-.-.--:;r ·fBD;~7"./.....i.....t
1 rt:-lIl:.' .'..'..'..'..'t···i
L.E '.•'.•'.•'."'f
SD -I ~............j
i
-..'.'.'.'l··I5rt:-I .U ,a,..!"..".0".0"."j '"j
U rt:-I -'\"...;;"'-""1 i ~~::.
'L.E ..'_.,.:..' .'.'.--!I
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A
U N
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A .....~.....
B
L ~)
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t'"
A .....
~
Fi;~~~
~..
E
A F
T
---------~'r:.-'~::-'.'---~'_"_.__.~__L...........'------'.~'--~'--~'--~~.......-----'
mnD i ,
2nD I I Ii.i ,I
~rl:It,.••
~E.E.·tt
10%
5D%
3Lf 35 3S 31 3B 3li
CALENDAR ~....JEEHS
E~EGINNING AUGUST Lf
CIllllM Spawning Area ln
Representative GrolllPs 2 Jt 3 Jt 4
Under Matlllral Flows
Figlllre Elt31t21t63
3332
BnD
SDD
5DD
linD
LfnD
1nD
3nD
~"4 I
E N
I
G T
H H
T 0
E U
D S
A
U N
0\::"D.....
A 0\::".....
8
L ~)
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A 0\::"....
R Q
E
A F
T
c
..in
Sites
...'.~..'
lot...-
lot..".'.......'
...'....:'..........~r.;.i
..........:~1
.•loa.'lot......~!-.....-...~.-••.."ilor:--....I.e,;."..i
........i..".,'..j
.....................,..~..';.~..........................~........;.
...."••~.......-:....,-!.....
.."."~..":..~~..to.i ."I"t..:i.....;....I....".....to I ..•.".•".--f'":::--r......".•-••","..."....to."."....._~-{e :~~~~(I ~t ~~~_.."•••".,L I L I t ~-••-..L ,
-..........."-.....-..lot.."••.__.-~....eo'..,.-........"...-..-...."1 ....••••••-~.""'t:.:-''''''l~''''-''"f'-,..·,1."_••....,••lot...~...."."...'."I.E lot •.'~~rtti:..-.!-"."'................"..J...... ...... ....,:.to·.. ..EE..E ....~
,I ..."j 10 ...".to "•••".... ..~1:'1::I I...t... ..lot.lot....::::EU%
D-r------:-r-!.qD%
40 .·tU I 43 ;4 4 41 48
I CALENDAFt ~""'EEKS
B,EG-INNING m:ITOE:ER I,
ClltJlM IIncllJlhation Itflf&ea
IFG and DIHAB Model
Undelf&NatllJllf&al Flows
FigllllFe Elt31t21t69
3D
aD
m
mD .:•
qD
SD
lD
SD
5D
4D
~..!J I
E N
I
G T
H H
T (1
E U
0 S
A
U N
S D
A ..;:-.....
B
L (1
E F
A ..;:-.....
R Q.
E
A F
T
".fl':
.~
nunl I ,
..in
2 Jl 3 Jl 4
Elt3lt21t 70
tiEl414S4ti434S
CALEN[)AIi ~-~EEHS
m:TOE~ER I
ClfillJlM InClllhation Area
Repr1tl2tsentative GrolllPs
Under Natllral Flows
Figlllre
BEGINNING
42til
mD i I I I I I I i I
tiD
tHID
BOD ..,-;:;:~-~•.'.'.'.'.'.'.'I:"...,
•'.•••••••••••'-""'r.,•••••••••"a:;••••~•••••••••~-ro.".'..'..''...•...•..'..'..'.~~~~~~~~~~/~~~~~A~~~~~~",,~~~~,
/~~~~,'~///~~~~
..••...••.....to .\.'.'•.'.'.'.'.'~_'__....__,.' .'.'.' .'.'.'• •.' .' .' .' .' .' .'.<<.......-..•..... ......'..,..,..,.v·,.,,.,..L.......'.'••,••,.,'•••'••••.. .~~,~~~~~j j ~'~.~~~~~~~~,.~~
..'"••,,.'.'.' .'.'.'••,••' •-,.::;.,.,.' .' .'••,••,.' .' .'.'.'.'.'••J
5[1[1-1 '~•••.,••••••••/•.•••••••••••••••••••••••••••••/.~•••~••••••••••/'•••••••/•••••••••••••••••••••••x..::'.'.' .' .'..,..,..,..,..,.'- ' ....:.,"<'..............,<'C'J<.:«::...:::>::>:::....::....::>::::...:::::::: ::.....:;::::..-.::>:::>:::....::....::..-.:::
""'--<:::-e:::..•.../..../,.,..........<•....,....,..,,..,~--~.,-~..'......
3DD
tiOD
1ml
SOD
2DD
~-~l
E N
I
11-T
H H
T 0
E U
D S
A
U N
0.::-r)-'
A .-~
E~
L 0
E F
A .-.:.
Ii l-l-..E
A F
T
\
\
j
\
l
I
1
,(
-I
j
1
:r
U
II
I·
LEGEND
MAXIMUM-NORMAflNG LEVEL-------OPERA I
EL.2000
RS ARE IN
-Z300-~~~;0~BOVE MSL
--SLOUGH---
TRIBUTARY
WATER BODIES
,
.../
· J
]
j
J
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)
J
)
J
J
J
)
J
}
lJ
16
u
o
·•••.I';..
I •. I I ..,..,
•••It\.I J .\.
I"!..J •
:\J ,\~I,.'".•••\I,•,..•~IU""I,..
I •I1nl
I ,VV
••
•
KW ........u.Q.G li(P ocr NlV ore JtlN FrS *lA CAt
1981 1981
Ii
~-t,..
r
2
10 ...
fT1
:J:
~
D-t
S ~
o
o
I )L£OEND'OR ••_.WAlIII:ILA -WAT~FILLING (JP[RATION _
FlAG'YEASf FILLING USING 1981 CLIMATE DATA
,~ICT'O CJJTI=LDoI T£HP£RATlAL
J _ -__- _-INI=L().l T'£'lP£RA1UAE
15
u
I.1J~IO
....aa:
I.1Jn.
::t:w....,
e;
...J
~
::::lo
o
..,
I'I,.,
I ,I I
I I
"I.,~r-...I --r '
•-I ,,i',
I ..'""-..
"..'It ~•"f\
I ,",••\•
I I ',-~."
I It'-,,,
I'•I II ,
•.
I "
•,,
I1RY ...uN ..u.lUJ lii:P OCT Io4)V O£t:JtlN FEB JIIM ~
U182 1963
15
o
L.D:lENJ.~......WROIFILF -I.lATANA F1LL(tQ C1P£RATION __•
F1RGl YEAR F1L.LINO USING 1982 CLIMATe:DATA
----PR£OICTILD ClUTFLDoI rli:HPtllAT\.AIi:
- - - ----1t.F1..().l TDF£RAllAL
SOURCE:APA 1984e
WATANA RESERVOIR
OUTFLOW TEMPERATURE
DURING INITIAL FILLING
FIGURE E.3.2.72
6
.<{
w
;f ~4
."
W C....0
~g 3
'"..c::>'.!::.
ow 2
I-:r
~
W;;
J..
SUNRISE SIDE CHANNEL J
Breached t I
------]
1
]
30 50 70
(Thousands)
SUNSET SIDE CHANNEL
.j
\
]
!
I
l
I
1
}
J
FI GURE E.3.2.73
(PAGE 1 OF 6)
30 50 70
(Thousands )
MAlNSTEM DISCHARGE AT SUNSHINE (ch)
a.reached t
JUVENILE CHINOOK WEIGHTED USABLE AREA IN
REPRESENTATIVE SITES LOCATED IN THE LOWER RIVER
2
<{7
w
'"<{6
w ..
."....Cca51 5<{:>'"0::;)..c
.!:;40
W
I-:r 3
~
W;:2
1 -----
10
7
6..-lr 5
<{
W
IX 4<{......w c....51ca 3<{"'"0..c::;)I-
04---.....----,r---..,.----.----,---""T"'"""------I
10 30 SO '70
(T hCllSOnds)
9
TRAPPER CREEK SIDE CHANNEL10.,..-----...:.:.:;:..:;..;,.;:;.;..~.::......:..~:.....;,.-------__,
SOURCE:ADF&G 1985 RPT.7
ROllY CREEK MOUTH40
35
...30:
<l:25....a:
<l:....-g 20...0
""!<l:0<It ..c:.15:::l .!::
ew 10I-
:I:
C)
iii
3:5 -------
0
10 30 50
(Thousand.)
70
30 50 70
(Thousand.)
MAlNSTEM DISCHARGE AT SUNSHINE (ch)
...4...
~
<l:w 3a:
<l:
w ..
"...c...~<l:
<1'1 ~20:::>...c:.
l-
ew
l-
X
C);;:;
~
0
10
KROTO SlOUG H HEAD
9
8
.,;7
a"
6<l:wa:5<l:.
"...c...~""4<l:~
<It 0..c:.:::l l-
e 3
w
I-
:I:2C)
iii
3:....
0 -..---0-----
10 30 50 70 90
(Thousand.)
SUCKER SIDE CHANNEL5
FIGURE E.3.2.73
(PAGE 2 OF 6)
MAINS TEM WES T BANK
t Breached
30 (Th~and.)so 70
ISLAND SI.DE CHANNEL
.....Breached
...-..---
30
(Thau~sands)
so 70
CIRCULAR SIDE CHANNEL
t Breached
30 (Thausands)SO 70
MAlNS1'aI\D15CHAQGE AT SUNSHINE Ids,)
FIGURE E.3.2.73
(PAGE 3 OF6)
BEAVER DAM SLOUGH6
----5
~
<I:w
IX 4<I:..
w ...,
c....~co
<I::>
II)0:::l .c
3C\.!::
w
!i:
C>w
~2
1
10 30 SO 70
(Thouaondsl
CASWE MOUTH10
9 -".-----.::8
j 7
<I:w
IX ..6<I:...,
~c
0;5
<l:0II)..c
:::l .!:4
C\w
0-3x:
!:2w 2~
----1
0
10 30 (Thousands I SO 70
BEARBAIT SIDE CHANNEL
1 0.9
!0.8
<I:w 0.7IX
<I:
~:;O.6
co c
<l:0~g0.5
.c
fil .!:0.4
0-x:
C>0.3
W
~.
0.2
0.1
Breached
30 (Thousonds)SO 70
MAINSTEM DISCHARGE AT SUNSHINE (chI
~-
FIGURE E.3.2.73
(PAGE 4 OF 61
GOOSE 2 SIDE CHANNEL
8
7 ,
I,-6 I
!,,,
4:5 ,...,
"".4:.,.....4'...c ....2...,
4::>,
0...J:.3
,
:;).=,
a
,
Breached t I..,...2 ,
X I0IiiI:::I
I
I
0 r
10 30 50
(Thouaanda)
70
---
BEAVER DAM SIDE CHANNEL
4
3.5
~3lr
4:2.5.....
4:....2..c...~...
4::>
1ft 0
:;):;,'.5
a...;;.~··-1
o
ii
:::0.5
...
]
J
7050
(Thousands)
30
o -I=-=-.=.--::.;-:.:-:.;-..::,-=---=--:.:-:..;-::..:-:..:-.!.::::::::;=:::::::!!...-,..----r---r----.J
10
SAUNA SIDE CHANNEL6..,---'---'---'--'----------------,
t Breached
30 SO 70
(Thousands)
MAlNSreM OISCHAIIGC AT SUNSHINE (ds)
4:4..a:
4:.
3...........c...24::>'"0:;)J:.
a =2
w...
·x
-0
iii
j:
0
10
FIGURE E.3.2.73
(PAGE 5 OF6)
1.
HOOLIGAN SIDE CHANNEL
-Broached
30 50 70
(Thousands)
90 110
RUSTIC WILDERNESS SIDE CHANNEL
----
_Broached
30 (Thousands)SO 70
LAST CHANCE SIDE CHANNEL
9070SO
(Thousand.)
MAINSTEM DISCHARGE AT SUNSHINE (ef.)
30
FIGURE E.3.2.73
(PAGE60F6)
WATANA WRTER SURFACE ELEVRTIONMONTHLYSUMMRRY
STAGE I
WATANA 2000 FT.NO DEVIL CANYON
2050...---.-----.--..,.--.----....-..,.--.----....-..,.--.----....----.
_2000 +--I--I---+--I--I---I=.=""'"'.I-...-j-I---+-~I--t---i
~~~.~.-
U-~
z
.;:1-95ll+--1I--+-.,...j.,..........,."-if",.......=-""=..,f=.......,.jf,,,...........,f.,;.;.....~=ii=-I-~
~r'-'
>w
...J
w 1900 -F~I--I---1--I--t---1---iI--I---1---iI--I---i
w ......1"-._.
ucr
U-
0::•••••••••••~1850 +-........,~......-,...,....-+---:-11-...-1-....-+--1---1--+--1--1---1
L DENIEiMAX--_.-._-
.----......-.---,-.----.------.......-....---.....----......-.9it-:-:;:"",,-l=I·-n-n-I--...,-...-----I ..···.......-...-I··..--11--·+--··1··..-·..·-m·~d:=..=..-=t..=...=.J ..
..........
1750 +--'I--!---I--1I--I---I--I--l--+---I--l---I
..JAN FEB MAR APR MAY JUN ..JUL AUG SEP OCT NOV DEC
SOURCE:APA 1985h
EIGUREE.3.2.74
]
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1
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j
1
1
1
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1
j
l
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1
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r
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H I
T L
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5 5
A
B 0
L F
E
5
A Q.
R
E F
A T
1 .
6
5
.ti
3
22 2ti 26
E3 5TA£rE I
(j ~ArURtiL
:..::.:
2S 3D 32 3ti 36
CALEM~AR ~t.lEEl{5
BE£rIMM~M£r MAt~t 21
38 tiD
~rJ:11:,.••
Etf.'"tt
50%
r.t:I:'l:11:,.••"tu ....tt:
Filorult'"t.e Ett3tt2tt 75 :
Chinook Realt'"t.ing Habifa t Alt'"t.ea
Undel'"t.Sta:Bre I Flolttlf RegiItile
In All Neplt'"t.esenfative Glt'"t.oups
UJ%
5D%
qD%
till3B
NitTUR'itL
3&
t;3 STAfrE f
Jti
ti
3
5
Ei L .:•"""""."w·'"""" •L~t.I f
E N
I
fr tt:1
H I
T L
E L
~I
D
U N
5 5
A
E::D
L F
E
5
it Q
R
E.F
A T
2 ~I ' .i ri "I ""I r 'rU'["""W r """W I 00't
22 ~HI 2&2B 3D 32
CAlEN~AR .~t-lEEHS
i IE::EfrINNfN&MA\t 21
FiguJft.eE~3~a~7~i
ChinooJ.k Reak~ing Babitat Al.~ea
Undel.~i Stage I Flow Regiine
In Rep~~esentative (il.~oups 2;3;4
'-----~~--.~--'''-----'~~--~-'"--'"---
~rl:Il:,.",LE.·tt
El 5TA&E I
...MtiTURtil............,r
31 3B 3li3535
CALENDAR ~"~EEHS
BEGINNINl::;AUl::;UST ~
.ClU.JtM Spawning Area in
IFG and DIHAB Model Sites
Under Stage I Flows
Figllll~e Elt31t21t 77
m%g~Q2g~~g~~~~~~~g~~~50%
mD
liD
BD
10
SO
50
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3D
20
."
m
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[J
I
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CALENDAFt ~w.-IEEHS
BEGINNING·AUGUST ~
CllltJlM Spawning Al:itea in
Repl:itesenta tive Gl:itOlIlPS 2.lt3.lt4
Un~el:it Stage I Flows
Figllll:ite Ett3tt2tt7B
~w.-I I mEmEN
I
G T qEIa
H H
T 0 Bnn
E U
[)S 1nnA
U N ::I
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-.....---1 -------~-,.---------~----
m%
50%
110%
5TA&£1
NATURAL
tJ
42 4~4 4 45 4S 41 4B
CALEN[)AR ~"~EEHS
BE~:r-iNNING OtTOtER 1
Cl'ttllJlM InClllhation tfIJf&ea in
IFG and DIHAB Model Sites
UndeJf&Stage I Flows
FiglllJf&e E~31t2~79
41
.'0i l I I I I'•I
40
---------------------~l_==:_:llmo,
110
~:~
.~..).~SO-l,~~:~·x>*·:·:}:~L..~,~__
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•0"....0".....>.L---..~.....00 .,.""'I'~.0q.'.•'..'.•'..'..'.'"':".oMl.i."•.:....;.':::: :::.
.,....,_..,.....,._,:,:::,::.:::::,::..:::::,::::::::::::::::::~:::;::::::~.::::::::::::::::::::::,:::::::::::;:::::::::=:::;::::::~::::~:::::::::::
~~1
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...........
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IDD i ~I II l I I I I
LtD L~I Lt2 qj£Lt q Lt5 qS ql LtB
..Cl'iILENDl'iFt ~"~EEHS
BE~::rINNIN(:r m:TDBER Ii.;
CIlllllM Incllllhation Alfttea in
R~p:f&esentative G:f&OIlIlPS 2.tt 3 .tt4
Undelftt Stage I Flows
Figlillftte E1t31t21t:B9
~DD
2DD
3DD
mDD 'i ,i
qDD
BDD
~.....I
E N
Ia-T
H H
T 0
E U
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-::::0...
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L 0
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l'i .-.:::-
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~---~------''----'--------------
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15 iii I I I I Iii I I I 15
u ~,
;001 ,j~4tJ I·P1 I W=t=4oo~
w "..•I .~i-1£9$*1':':I'~f t 2L t:l ~
:::)-
o
LEGEND'WATANA OPERATION IN STAGE I
CASE E-VI.NATURAL CONDITIONS AND HIGHEST LEVEL
----PREDICTED OUTFLOW TEMPERATURE
--- - - --INFLOW TEMPERATURE
"TI
G)
C
:0m
m
(oJ
II;)
Q)
NOTES.
SOURCE:t/fE 1985h
I.INTAKE PORT LEVEL I AT EL.1964.6 FT.\599.9m 1
2.INTAKE PORT LEVEL 2 AT EL.1926.6 FT.58T.4m
3.INTAKE PORT LEVEL 3 AT EL.1998,6 FT.6T6.8m
4.INTAKE PORT LEVEL 4 AT EL.1860.6 FT.664.2111
6.INTAKE PORT LEVEL 6 AT EL.1812.5 FT.662.6m I
6.CONE VALVE AT 'ELEVATION 1791 FT 1646.0 m)
T,SPILLWAY CREST AT ELEVATION 2149 FT (664.Tml
STAGE 1 WAT ANA RESERVOIR
OUTFLOW TEMPERATURE
"G)
C
JJm
m
Ul
I\)
co
I\)
i
i
lBO ----'----,.4-.L---r--...+I-.,-----.----T---.,I
70 i 'i:I I i
l I
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tSO i •I
!',I,I
i i'I',;I'il •
150 !''I'•I"W • ,I
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;:;140 ..•,--t-,I,'r;-",-:~'""':--
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110,I I .'_,\
,i ,I '\
'i i .~'i I
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90 i I !
i i
I'()V ,:DEC ..JAN FEB MAR APR
I [:A-A5KA I'O\IER flUT ....ITY
L£GEMI,,i l1li11'"FROJ[ct I
-----'ICE FR(M'I!Sl£lTNA RIVER
•-- - -~- --~2£ftO 00Jflf[I~"r WEATHf:"A PERlioD I 1 NOV 81 -30 APR 82 PROORESSION (y=ICE FRONT
FLOW CRSE 'ElVI TEHP,INFLOW-MATCHING &ZERO QEOREE lSOTHERH
STAGE I WATANA .,tmlA-£BRSCO ~IHT VEtfll.RE
REFERE"CE RON NO.,910lENS ____•IIla.IU
,
SOURCE:EXHIBIT E.CHAPTER 2
,!'flI ---'
AGGREGATE CHINOOK REARING HABITAT QUALITY INDEX FOR
LOWER RIVER SIDE CHANNEL I SIDE SLOUGH HABITATS
0.07 ..,.------------------------.
0.06
0.05
xw
0
.~...0.04«
!::
CD«
J:
0.03
0.02
0.Ql +-E1::::::S:=a-r----r-----r-----r---~--_._--_1
10
SOURCE:ADF &G 1985c
30 50
(THOUSANDS)
MAINSTEM DISCHARGE AT SUNSHINE (cfs)
70
FIGURE E.3.2.83
I
1
!
I
I
I
I
I
]
l
'~j
,I
,I
FIGURE E.3.2.84
70
0.1
0.12
0.14
AGGREGATE CHINOOK REARING HABITAT QUALITY INDEX
FOR LOWER RIVER TRIBUTARY MOUTH HABITATS
0.16 .....-------~-------------__::I___,
0.15
0.11
0.13
0.07
0.06
_QLO_5~_~~~~__c __~.._
10 30 50
(THOUSANDS)
MAINSTEM DISCHARGE AT SUNSHINE (efs)
0.08
0.09
SOURCE:ADF &G 1985 c
xwo
Z
.J"" 0?~
J~
/
LEGEND
-"'---NORMAL MAXIMUM
OPERATING LEVEL
EL,I455
-2000 CONTOURS IN FEET
ABOVE MSL
-- --S\..OUGH
--.•_..~TRIBUTARY
o 2 MILEf
SCALE F !
"'"".
-'"
"-.".
\.
\.
IJ"L WATER BODIES TO BE INUNDATED BY STAGE ]I DEVIL CANYON RESERVOIR'
FIGURE E.3.2.85
J
J
o}
1
1
OJ
'J
1
1
1
1
1
oJ
'J
1
l
1
J
r
DEVIL CANYON WATER SURFACE ELEVATION
MONTHLY SUMMARY
STAGE"-
WATANA 2000 FT.OEVIL CANYON 1455 FT.(ORAWOOWN 50'l
1500.,.--r---r--y--.---,.--,--,----,r--,--,--r---.,
_1475 +--t--+--+--+--t--+---t-~r--+--+--1----l
I-u..
z r::::7~-.:::::++--::-=-'=t-::--::-~:j:::-""::~~--:..:-:.=-~--:.:..:--=t:-,;;;-~-J-~--~-=-:j::-~---:r=-"-'--=--='=-:::-i=-=-=l-;~1450,.
r-cr>W
.J
w 1425 +--t--+--+--+--+--+--+--t--+--j--+---I
wucr
lL
0:::
i7J 1400 +--I---+--j--+--I---+---t-~f--+--+--t---l
L _GEN!
~MAX--------
r-AVG-~-+---
~1375 +-_t--+_-+-_+--I-_-+-_+-_r-;H..;.;IN...;..-+-_---''-j-----'-!--1
1350 +--I---+--I--+--+--+--+--1I----I---:--I--+--1
..JAN FEB HAR APR MAY JUN ..JUL AUG SEP OCT NOV DEC
FIGURE E.3.2.86
SOURCE:APA 1985h
__.________._...---=..J.-:A~N~FE:::.::B:.._.:.H:.:.R.:.:.R~RP_R------.:H..::.R.:.:.Y_.JUN ..JUL RUG SEP .OCT NOV OEC._._.__~.
]
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l
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!
l
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I
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1
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r
FIGURE E.3.2.81
.__.."
I--
_..."~""..-'~--I-'-~~--~--..···I-··
1---
1-··-··
_._1-.-.
..•..1-'--
..-----.;-;;-.-;;1=
1-
_2000 -t--+---if--+--+--';"'-l--+--j--l---b=d--t-~
l-
Ll.
WRTRNR WRTER SURFRCE ELEVRTION
MONTHLY SUMMRRY
STAGE"
WAH~NA 2000 FT.OEV I l CANYON 1455 FT •(DRAWDOWN 50')
1750 -1--+--1--4--+-+-4--I1--4-+--I--.\--I
z
o 1950 .,I--.---+--+---l--+--r..:.=..:..=+-+---l--t--t---l----l;:.--
cr>
W
...J
w 1900 -1--+.-.-..-..1::::,=::l--+--r--+-+---l--+--t---l----l
wua:
....~..~LI._..-_
0:::~p 850 -t--+---if--+--+-;......,:.....j--4--jr--4-+--l--t-~
L GENI
0:::I1AX-'-'-._.
~RVG-4--i-
~1800 -t-_+--j_-+_+-_+-_t--t_4M.::J..:.;N~·1-''-'-"-4-'-''-'-I-~
SOURCE:APA 1985h
Ul."t.e Ett3tt2tt:B:B :
Chinook Real"t.ing Habifa f Al"t.ea
Undel"t.Stagre II Flow Regill~le
In All Repl."t.esentafive Gl"t.OUpS
m~"
5D~"
qD%
tiD3B35
5Tli&E II
3tI
!....!WliTURliL
EJ
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EIt3tl2ItB',:
I,Chin,ook Reak'"t.ing Habitat Ak'"t.ea
I Undel'"t.!Stage:II Flow Regilne
! .In Repll'"t.E!tSentative Gk'"t.OUpS 2;3.tt4
f
~t.I 1
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L'f t:lR
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FigUk'"t.E!t
--------------------~------------~'----------~
[II •iii ,•I
5TA&[If
NATURAL
m~{
Iin%
5D%
3t.t 35 3S 31 38 31i
CALENDAR ~~~EEKS
BEGtiNNING AUGUST t.t
CllllilM Spawning Al:&ea in
IITG and DIHAB Model £;i tes
Undel:&Stage II Flows
Figllilre Elt31t21t 90
333i:!
mDl I
liD
F
T
f
N
T
Ho
U
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S
Q.
o
F
A
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D.-.:}
3~31SJ6 l 31 3B Jq
CALEINDAR ~~~EEHS
8EGINNlNG AUGUST ~
ClrtllM Spawning AJtitea in
RepJtitesenta tive GJtitOl.lPS 2.Lt3,lt4
UndeJtit Stage II Flows
Figl.lJtite Elt31t21t 91.
~rttt".·
;E L.E."tt
I:1:rttt".·"EU ..·tt
m%
E]STA&E II
17 :::::1 NATURAL:'~::......:
~....i m00-r---~E N ;--f !
I
G T qOO
H H
T 0:BOO
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D -=-100.-.!"
A
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A -=-i.....SOO8
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'------'------,---------'----------'--~~---~'---'---'----,
WATURAl
5'ftHrE IIr;]
43 44 45 41i ttl 48
CALENDAR ~...fEEHS
BEGINNIN~::r m:nlBER I
ClUJtM InCIlJlbation Area in
IFG and DIIHAB Model Sites
Under Stage II Flows
FigllJlre Ett3tt2tt 92
H''l:tt..-EE..E ....it~,~<s is ,is~L ssE r-1~g~.............u:::..' .'.'.:.:,$..~
•..~..•••0"••••
•.".'."_0.
0
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E N
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U N
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IA S
IS
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IA -:::".....
'Ft Q
IE D
A F 4D 41 42T
DD i I I fI I I I I I
4D 41 42 tI~4 tI 45 tiS 41 4B 0
CALENDAR ~'-JEEHS
BEG~NNING DCTDBER I
CI)IlJlM Iru:rr:IlJlba tion AJihea in
R~PJi&esentative GJi&OIlJlpS 2.tt3.tt4
U~deJih stage II Flows
FigllJlJihe Elt31t21t 93
lDD
aOD
m%
~rt:lf:".'::JU.'"tt
ttD%
mon •:i
linn
BlI"l~~~·'···I IL.E ..•..!....."e'.'M:J555 ~{)·::.?h::;ry..!..'eeR*1"'M!..tt'lOD ...'l'·l.'.' .'.'."'..!
S[m
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tlon
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[::::::Nil)TURl)L :"':::.,::::.,::~:,::::,::::::::::::::::::::::::::;;:::::;::::::::::;::::;:.::::;:::::;:::
~v.-I I
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8
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______0 ___0 _
~'________0 ~•__~
ALASXA POwER AUTHOR1fV
SlO1HA H"fTlOO{l [C 1H"IC PJtO..f"C1
SIMULATED SUSITHA
RIVER TEMPERATURES
RIVER MILE 150
STAGE n
~.:..-=:ol.
---'1-I'-
LEGEND
SIMULATED NATURAL
TEMPERATURES
SIMULATED TEMPERATURES
PHASE 2 OF TWO STAGE
PROJECT (FOR COMPARISON)
SIMULATED TEMPERATURES
STAGE If OF PROPOSED
PROJECT
NOTES:
1.CLIMATOLOGICAL AND
HYDROLOGICAL DATA
PERIOD MAY 1981-SEPT.
1982
INFLOW TEMPERATURE
MATCHING POLICY FOR
MULTI-LEVEL INTAKE
STAGE 2 OF 3 STAGE
PROJECT
AVERAGE WEEKLY VALUES
E-VI FLOW REQUIREMENTS
DEVIL CANYON DRAWDOWN
OF 50 FEET-2 LEVELS OF
SHUTTERS
\\.,I \ I ...'
, \ I,,,
J ".,"II ,I I ,ro_
II ,I ,,-
I I •I II:~:':/
:'1\'•:JII'II I
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",..-:"
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...,..',,,
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\
\
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.../\"\\
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\~
1\
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II
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I
\•\•\~..r/----~..---..--/
',..,"",,-'
'....,-...'--..."---"
MA Y JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
1981 1982
",,,\
, I
, I,;,,,
/,"\..
" I ~
I
' ,I ,
"'\I It,.}',Ii
'/\,I ,""~:\'I.'1.I"
"I,',~
l
l
l
SOURCE:EXHIBIT E.CHAPTER 2
o
4
2
6
8
10
12
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fll
f"
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to
./>.
C
D
E
G
R
E
E
S
...l ...SKA POWER ...untOflITy
SlGlHA HTt_iClll£CUUC NIQ..ECJ
SIMUL'"TED SUSITHA
RIVER TEMPERATURES
RIVER MILE 130
STAGE II
~'-I---------I-I'-
NOTES:
1.CLIMATOLOGICAL AND
HYDROLOGICAL DATA
PERIOD MAY 1981-SEPT.
1982
2.INFLOW TEMPERATURE
MATCHING POLICY FOR
MULTI-LEVEL INTAKE
-3.STAGE 2 OF 3 STAGE
PROJECT
4.AVERAGE WEEKLY VALUES
5.E-VI FLOW REQUIREMENTS
6.TEMPERATURES SIMULATED
BY SNTEMP FOR PERIOD
JANUARY -MARCH SHOULD
BE USED WITH CAUTION AS
AN ICE COVER MA Y EXIST
ON RIVER ANDSNTEMP
DOES NOT SIMULATE
TEMPERATURES UNDER AN
ICE COVER (SEE RIVER ICE
SIMULATIONS)
'7.DEVIL CANYONDRAWDOWN
OF 50 FEET-2 LEVELS OF
SHUTTERS
LEGEND
SIMULATED NATURAL
TEMPERATURES
SIMULATED TEMPERATURES
PHASE 2 OF TWO STAGE
PROJECT (FOR COMPARISOt
-SIMULATED TEMPERATURES
STAGE 2 OF PROPOSED
PROJECT
I .....,i,I -'I i,'
--,'j •, I "\~I'•'1 •
...,,"
"'.'
1
1',1 •",,....'I\j'..'\·'f -/"
,"'.'....",'''\',
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\
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,..'I',"I,' , ,I
i,".,
,1
MAY JUNJUL AUG SEP OCT NOV DEC JAiN FEB MAR APR MAY JUN ~UL AUG SEP"I Ii-I _
1981 ' ,1982
•"",,",....',,,..,,",...I..:\""",,",J.'\",~,"J'I'~\,!'I
J
4
J
SOURCE:EXHIBIT E.CHAPTER 2
4
2
o
6
8
12
10
TI
i5c
:Dm
f'I
c.>
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en
C
D
E
G
R
E
E
S
~-~--
.;...
~
ALASKA POWER AUTItOflITY
SLG'fNA UT'(..-tO£LlCfRJC rAO.1CI
SU,ULA TED SUSITNA
RIVER TELIPERATURES
RIVER L1ILE 1 DO
STAGE II
~.:..~I.___o\'I -
NOTES:
1.CLIMATOLOGICAL AND
HYDROLOGICAL DATA
PERIOD MAY 1981-SEPT.
1982
2.INFLOW TEMPERATURE
MATCHING POLICY FOR
MUL TI-LEVEL INTAKE
3.STAGE 2 OF 3 STAGE
PROJECT
AVERAGE WEEKLY VALUES
E-VI FLOW REQUIREMENTS
TEMPERATURES SIMULATED
BY SNTEMP FOR PERIOD
NOVEMBER-MARCH SHOULD
BE USED WITH CAUTION AS
AN ICE COVER MAY EXIST
ON RIVER AND SNTEMP
DOES NOT SIMULATE
TEMPERATURES UNDER AN
ICE COVER (SEE RIVER ICE
SIMULA TlONS)
7.DEVIL CANYON DRAWDOWN
OF 50 FEET-2 LEVELS OF
SHUTTERS
LEGEND
SIMULATED NATURAL
TEMPERATURES
SIMULATED TEMPERATURES
PHASE 2 OF TWO STAGE
PROJECT (FOR COMPARISON)
-----SIMULATED TEMPERATURES
STAGE 2 OF PROPOSED
PROJECT
.
"II
1.1
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1 ~\:
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I l'
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~
MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
1981 1982
SOURCE:EXHIBIT E.CHAPTER 2
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i170
f
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I
i150
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:....J.......140L !
0::I -----,---'1/\.---W "..--130 i ,---l :-;./~>,---'\,.......
'.~:;'f~n::I I,
120
1 1 1 /-:'\r '~1 1 I 1
l"!~..,I "~,--....I 1.1 ' IlID,,i 1
1
f ".\I I I ,,.i
•,i I'
I !',\.I •,•100 i I I ,i '.\I I I,
90 ,
APRI\OV IJEC .JAN FEB HAR
i ALASKA POWER AUTHORITY
l.£.GEN),
6U511!lA l'IlII.£olICEFRlM"!
SUSlTNA R[VER• - - - ---- --2f.I'tO lEJREE Itll:1MAl1 HEATHER PERIOD I 1 NOV 8\-30 APR 82 PROORES5ION OF ICE FRONT!i STRC£II f '&.ZERO DEGflEE 1soniERttIFLOWCRSEE-VI •INFLOW-HRTCHING
mR~-E1RiCO .J)INT VENT~EBJFT.~AHO(i]HN.2 PCfH6
REFEREt-a:R\.W.I NO.,eI 02ENX
_~·....._....u.·1 lUll.142i,
SOURCE:EXHIBIT E,CHAPTER 2
"1Ir,
'"--
Adult Inmigration
Spawning
Incubation
Juvenile Rearing
Outmigration
• I I •dD I I ..
..I I.
Range....
Peak
f--t
SOURCE:AEIDC 1984b
"11
G)
c::
::Dm
m
'Co)
l\)
lD
CX)
4)
~
;:)..e
4)
Q.
E
Cb
-
-
-
-
-
-
-
i-
-
-
1-
-.r-
-1-
-
-
-
MAY JU'N JUl AUG SEP OCT
Tolerance Zone
NOV'DEC JAN FEB MAR AP R
TEMPERATURE TOLERANCE FOR
CHINOOK SALMON
Adult I nmigration e--1 I ,
Spawning •I I •Incubation
Juvenile Rearing IOutmigrationIII •
!
!
-
-
;...
-i--
-
-Tolerance Zone-
-
,-
-
'-
-
....;"
i-
-
-I""""-
-
,
-
!
I I I I I I I.I I I I I I I I I I I I I I I I I I II I I I I I I I I I I I I II I I-I II I I I
i
SOURCE:AElqcI1984b TEMPERATURE TOLERANCE FOR
SOCKEYE SALMON
"'ll
Ci)
c::
:Dm
m
(,)
/IJ
<0
<0
MAY JUN JUl AUG SEIP OCT NOV,DEC JAN FEB MAR APR
Range••
Peak
f--t
'--------'
t---J
Peak
Range...---~
•1 I ..
81 I ..
L---.....:
Adult Inmigration
Spawning
Incubation
Juvenile Rearing I .I I I
Outmigration
I I I II I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
SOURCE:AEIDC 1984b
18
17
16
15
14
13
12
1 1
u 10
Q)9a.
:;:)8...e 7Q)a.
E 6
Q)....5
4
3
2
1
0
- 1
"II I -2
G)
c:::um
m
Co)
I\)...
0
0
-
-
-L
-
-
-
-
-
-
-I
-
-
-
-
-
-
-
-
MAYJUN JUl AUG SEP OCT
Tolerance Zone
NOV'DEC JAN FEB MAR AP R
TEMPERATURE TOLERANCE FOR
COHO SALMON
f--f
Peak
Range...
Tolerence Zone
JAN fEB MAR AP RNOV'DECUlAUGSEPrOCT
..I I .....I I •
MAY JUN
18 -11·T'-----r------+-....::=======:::======17 i
16
15
14
13
12 ~
11
10
9
8
7
6
5
4
3
2
1
o i 'I
- 1 I
-21 'i':iii iii i i:'iii iii i.1 iii Iii iii iii iii iii iii iii i ,iiiiii i ,
u
CD..
:;)....
C..
CD
0-
E
CD....
Adult Inmigration
Spawning
Incubation
Juvenile Rearing
Outmigration
'"r1
Ci)
c::
:D
m
m
IN
N...o...SOURCE:AEIDC 1984b TEMPERATURE TOLERANCE FOR
CHUM SALMON.
-~-'-~,--~~'---'
Adult I nmigration
Spawning
Incubation
Ju~enile Rearing
Outmigration
..I I ..
•I 18
..II •
Range
.------------..,
Peak
t-i
I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I-rr-l I I I '-TIl I I I I I I I
-
-
-
-
-
-
l Tolerance Zone
-
-
-
-
-
-
-
-
-
-
SOURCE:AEIDC1984b
,
APRJANFEBMAR
TEMPERATURE TOLERANCE FOR
PINK SALMON,
NOV'DECJUlAUGSEPOCTMAYJUN
-
18
17
16
15
14
13
12
11
u 10
Q)
9~
:3....
80
~
Q)
7Q.
E 6Q)
I-
5
4
3
2
1
0
- 1-n
I -2G)c.
:IIm
m
Co)
i\)...
0
I\)
;}
j
1
1
J
]
I
I
-I
.1
1
1
1
1
1
-}
1
1
t,
WATER BODIES to BE INUNDATED BY STAGEmWATANA RESERV'OIR"
[j
[J
o I 2 MILES
SCALE:F ::eiil
LEGEND
----NORMAL MAXIMUM
OPERATING LEVEL
EL.2000'
-2300-CONTOURS ARE IN
FEET ABOVE MSL
-----·SLOUGH
-"'-TRIBUTARY
STAGE JlI NORMAL MAXIMUM
RESERVOIR OPERATING LEVEL
EL.2185
PLAN
STAGE I RESERVOIR
EL.2000
r'.
FIGURE E.3.2.103
,,@"N.';...',
,"
...-.~
1
1
I
WRTRNA WATER SURFACE ELEVATIONMONTHLY--SUMMARY
EARLY STAGE III,
WRTRNR 2185 FT.DEVIL CRNYON 1455 FT.
2200
~-------~-
~----I-1-----~_.-I-
-2150 .._..
....I-._..-l-..............u..I---------.._--
-~..-.f---I---~.....z
::2100.........._........_..er>...........w ...........
..J
w2050
wuer
lLu=
~2000-
L =G£NI
0:::MRX---..----w RVG-....er MIN--.................
::z:1950
1900
JRN FEB MAR APR MRY JUN JUL RUG SEP OCT NOV DEC
LATE STAGE III,
WRTRNR 2185 FT.DEVIL CRNYON 1455 FT.
2200
f-._--_.._.
----
----I---1-----2150 I-i-•.....i--..................u..--..........-._-..........
I----.....--z --...........
::2100
..........
..-...........---,-_..._.er -~--..i--
••••p.
>
W .....................
..J
w2050
wua:
lLn:::
ffi2000
0:::L -GENt
w MRX-.._.--_.
....RVGerMIN-........----::z:1950
1900
JAN FFR .MQR .000 ...."v ",." "
~"~~-~-,-,~~....'-
FIGURE E.3.2.104
SOURCE:APA 1985h
DEVIL CRNYON WRTER SURFRCE ELEVRTION
MONTHLY SUMMRRY
EARLY STAGE III
WRTRNR 2185 FT.DEVIL CRNYON 1455 FT.
1500,.---r--,--y-....,..---,--..,--...,.--,--..,--...,.--,.----,
-1475 -t--+--t--t--j---j--+-+--t--il--+--!---j
l-u.
I
~14504--.::--++------+-1------t-l-----++------1=~==+_--.-+'---'--t=-='-=f=-=.=-:/:""-----+i_-_-_-i-j
l-a:>w
...J
w 1425 -t---t--l--1--+--I---I--+---l--jI--J.--+--i
wua:
LL
lr
If):l 1400 +---t--t--1--+-+-+-+--+-_II--+--\---1
L -OEN[eJ MAX-'-.-.-.
l-AVG-+--!f-
~1375 +---t--t--t--t---t--+--t--f-M.:..:.'.;.;N-j·;-''-'-''+''-'-''+--1
J
)
}
I
I
}
1
.l
.JAN FEB MAR APR HAY JUN JUL AUG SEP OCT NOV DEC
1500 ---.---,.----,;--....,..---,--..,--...,.--,...----,;---.,.--.--,
1350 -I--4--l---+--I---t--+--4--I----t--t---+---l
_1475 -I--4--l----t--t---t---t--+--t--;--t---t---t
.....-..t"u._.........+..+._..\............""-"-"..11....\-·1-······.\--\-
LATE STAGE III
WRTRNR 2185 FT.DEVIL CRNYON 1455 FT.
l
, 1
J.'
i
'\
II
I
,l
j
FIGURE E.3.2.105
:.............
JAN FEB MAR APR MRY JUN JUL AUG SEP OCT NOV DEC
SOURCE:APA 1985h
..............-.-.--------_02:-4-5'0""1===1==1==1==1'===--:-=-;.=~=-=-=-=~===-_.
l-a:>w
...J
w 1425 -I--4--I--+--I---t--+--4--t---t--+.-':":":'":-+--I
wua:
LL
lr
.~1400 +---t--l--1--+--......\---t---t--t--1
L
...._
O
-
E
-
N
+[--+---\
lr ...MAx··-·..c·-·
~AVG-t----t--a:MIN'.
:z 1375 -I--+--l----t--t---t---t--+--t---t---j---t---t
qO~{
~rt:It••b.EU ....tt
SO%
~m38
STAErE III
MATURAL..............
~
28 3D 32 34 35
CALEM[tAR ~t.lEE~S
~EErIMMIMEr MAttt 21
252422
4
""L".' .' .' .'".'.'-"",,--x:~......-b.'"b"-bb""b"u-;i:'::;';"~A7::"-••..-b "~"'<-....J~.0 ,_0° 0°eO eO 0°•·:....•..:·.....:;,.·..··h·~..·..')1·7~-:".......r ::;::.'!"Z.{7 '..S;0°0°":::....."X:~......%00'E;Ei::=ti c::C!(I C!L ( ( .(...." "!".....locO " " "LO "
3
S
1 .~t.l I
E M
I
Er M
H I
T L
E L
[1 I
tl
U M
S S
A
E~0
L F
E
S
A t:lR
E F
A T
e Eit31t21t.106:
Chinook Real"tting Habitat Al"ttea
Undel"tt Earttl~:li Stage III Flow Reginle
In All Repl"ttesentative:Gl"ttOUpS
r.t:nlt.·'U.·'ll:
10%
SO%
4[13836
r=":>!MATURfflto..::.....:
&:1 5TA&E III
30 32 3~
.CAlEM[~AR ~t~EEH5
SE&IMMIM&MA\t 21
i
i
282522
t{
1 ~"o "0 I"0 "'"0 0 0'"""..",0"0 ""..""0 ..0'..~
i
3 ...t'"r'j':"""~',,"'"0""""""~'(~",,"'''~~''''~0"...,~, ,f
2~1
!IE.3.a.~~?:,.I
~hinook Real."t.ing Habita t Al"t.ea
lUi,nde:r"L~.te ..Stage.II~Flow Reginle
In All Repl"t.lE!tsentatJ.ve Gl"t.OUpS
I
~t.fi I
E M
I
&tti
Ii I
T l
E l
[l I
0
U M
5 5
ff
E:0
l r
E
5
ff Q.
R
E r
ff T
Figul"t.e
-'--
".--,'----"------------
6 ..~"'"''''...,.."'"''.""""..."""'",'"L
m~~
5D%
~Hl%
4D38
~:i !:j or iJ F~i:i L
::~or i:i [~.E:~~~
36
[;;~J
EJ
34323D282624
5
3
2 i'".."f f"f'''''fiT I "I I
22
NI
E N
I
&M
H I
T L
E L
LE I
D
U N
5 5
A
~D
L r
E
5
A n.R
E r
A T
CALENLEliR ~t.lEEH5
~E&INNINrr MH\L 21
FicJful."t.e E1t3tt21tlJQi8:
Chinook Real."t.ing Habitat Al"t.ea
Undel."t.EaJ(tLly Stage III Flow Regilfue
In R~pl."t.esentative .Gll"t.OUPS 2 JL 3 JL 4
S ~......","'"r'''''..'...' "",.""'""..""".~
ID%
~rttt..·:EU.·tt
~m%
liD39
~~i:i -r Lj F~i:1 L.
:~-r i:i i:i·E:j i ~
3S
[j
Habitat Alt"t.ea
III Flow Reginle
Glt"t.oups 2 Jt 3 Jt4
3D 32 3li.
!CAlENtJAR ~t.lEEH5t
EtE&INNIN&MAt~t 21
292S2li
5
::'1
2-1 ......',"""I ,r;........·'.......,'~...........22 ~r'","'I'T""".r ,""'1 .,.1 I
3
"li
I i
i I \
Ett3ttatt11~9:
Itl:hinook Real"l·ing
Undelt"t.Late StageInReplt"t.esenta tive
I :
i !
i
~t.l I
E N
I
&-.M
Ii I
T l
E l
[1 I
D
U N
5 5
11
B D
l f
E
5
11 Q.
R
E f
A T
Figull"t.e
,
--~
~~'------'-------'~
~5 ~b ~1 ~B ~li
CALEN[)AFt ~...tEEHS
BECHNNING AUGUST 4
CIlllJlM Spawning Area in
IFG.and DIHAB Model Sites
Unde:rftt Early Stage III Flows
Figllllre E1t31t21t.119
~-...I I HUlEN
I Inl
G T
H H BO
T 0 10EU
D S bOA
U N SO.:::-D....!"
A ~~m:::..
B ~OL0
E F ao
A .~m~.
R (~
E 0
~i F ~a ~~~4T
o 5TA&E III
NATURAL
~rt:It•••Ef..E .·It
SO%
liO%
3~,35 3Ei 31 3a 311
Ct'FiLENDAR ~"'~EEBS
BEdINNING"AUGUST l.l,
ClU...lM Spawning Area in
l1FG and,DIHAB Model Sites
Under Late Stage III FlolfL!dls
Figl.lre Ett3tt2tt.1.1.1
~..~I mnEN
I I1n
G T
anHH
T 0 1nEU
0 -;:Ein-A
U N sn.-0.:.
A S l.ln
13 3nL0
E F E!n
A S mRQ..
E n
A F .,~'ool:T
...........:::::~:::::::: :::::::::::;:: : :.
ST~&E III
F:':::::l M~TUR~l
t.::.....:
m~{
sn%
I1n%
-r-'~-----.~.~~'-----------''---'~
:::5 36 31 3B 31i
CALENDAR ~""'EEHS
BEGINNING AUG·UST tt
ClllJlM Spawning Area in
Representative GrolllPs 2,1t3,1t4
LlndeJt1t Early Stage III Flow s
Figlllllftte EIt31t21t1.1.2
~.....I mnnEN
I
G T qnn
H H
T 0 Bnn
E U
D -;:1nn....
A
U N bnn0.:::"D.....
A -;:....snnB
L (~
E F ttnn
A 0.:::":::nn.....
R Q.
E 2nnAF
T 32 33 3tt
EJ
:."::..::
STli&E ill
thiTUfhiL
m%
SD%
qn~{
,
35 3S 31 38 3b1
CALENDAR ~~EEHS
BEGINNIN~::r AUGUST q
i
Clllf..'lM Spawning -A:f&ea in
Rep:f&esentative G:f&OllIlPS 2;3;4
Under Late Stage III Flows
i Figllll:f&e EIt31t21t.1.13
I·~I U:nHlI::N
I
~::r T blOD
H H
'r C~BOD
I::U
D S 100A
U N SODi:::D
l=i 'i::"....sonr'::.
L 0
E F 40D
l=i S ~~nil ::'::'1
I:t c~I
I::
l=i F 20D:
32 33 i 3qTI
[]STA&E III
.NATURAL
~~tt,..,
E&I."tt
~~tt,..'
;EE..E ....tt
~~tt,.••tu ....tt
'---------~'--~---'--~---'-------'-----------------------'
1::>:::1 NfiTtlRAL
r;:]5TAtrE III
4~44 45 46 41 48
CALENDAR ~~~EEHS
BEGINNING DETm~ER I
CI1tIlJlM Incll.llhation Area in
IFG and DIHAB Model Sites
Under Early Stage III'Flows
Figllllre Etl31l:211:.1.14
~r1:11:._-EE..E ...IiI~r1:Il:,..'-..'e"t!;;E f.!....IifYX-<X.x:S i[$$'.:'s e,ee TOO'e ttO%"t·..·..·dt ..L '1\0 -t.c::::,7:;:.:. . •........................
~--.I I
E N
I
G T
H H
T 0
E U
D S
A
U N
S D
A S
B
L 0
E F
A ~.~.....
R Q.
E 0
A F 40 41 42T
-ttL I Hl%
50%NATURALL.::::..J
:>).,)10,lot I l:lD%
E::':l 5TA&E (((
45 4&41 4B
CALENDAR ~4EEHS
BEG~NN(NG m:TOBER (
ClU.JlM InCIlJlhation AJf&ea in
IFG and DIHAB MOdel Sites
lhl£deJf&Late Stage III Flows
I FigllJlJf&e Ett3tt2tt.1.15
~~(
E N
I
G T
H H
T 0
E U
[)S
A
U N
S D
A S
B
L 0
E F
A -::".....
Ft Q
E o .'A F 40T
---'~'----~-----"-----'-------------'-"--"-------------"--'-"-"--~---~
STti[i.[I I I
m%
~1:'1:1t".,
~EJ:."tI:
qD~~
4a 43 44 45 4S 41 4B
CALENl':lAR ~-...tEEHS
8EGINNING OETO~[R I
.ClU..'lM IncllJ.bation Area in
RepJt1tesentative GJt1tOlllPS 2 Jt 3 Jt 4
Under EaJt1tly Stage III Flows
FigllJllf&e EIt31t21t1.1.6
NtiTURtil
~~f mooN
qDDT
H BOD0
U 10DS
A SODN
D srm....::::..
~nD0
3nD~EJF
-1 l:;:-"'::jSanDL::::..lQ
mD
41F40T
45 4S 41 4B
CALEiNt~AR ~....fEEH$
8EGIN~ING IltTDE~ER I
C}llll~Incllf.bation A:f&ea in
Repi:&esenta tive GJt1tOlIf.PS 2,lt3,lt4
Und~Jt1t Late Stage III Flows
Figllf.:f&e EIt31t21t1..1 '1
mit.·~·~:~~>-.s.:i -\'\\S","J s,''0<',<:::<Z»>S:';SS:-01 ~~.~.-"IL -.t_.~·-k·~·{i{......'-a:::::<.to."""-,u.·'"tt
~....f (
E N
(
G T
H H
T 0
E U
[)$
A
U N
$[)
A ....'.......
8
L 0
E F
A .....,:..
R C~i7 w I 1···..···1
E mD !..::.....!.
A F 40T
._-------------~--_.---~
___'--------..".''-----...J
:(...;'\
,~,
190
no
tSO
150
w
-.J.......1..coL
lr
W 13:>>.......
0:
120
110 I ,---,
100
90
I
NlV DEC
,---
-J\-~
~~
-.'
.JAN
f.\
-~
1
FEB
,
'1\
.~
MAR APR
"G)
C
JJm
m
c.v
I\)
--"
-"
(Xl
LEGEND,
-----ICE FRONT
- ---------ZERO DEGREE ISOTHERM
SOURCE:EIXHIBIT E,CHAPTER 2
WEATHER PERIOD:1 1'0\1.71 -30 APR 72 .
FLOW REGIME:LATE STAGE '"
FLOW CASE:E-1ZI TEMP RULE:NATURAL
REFERENCE RUN NO.:7120CNA
SUSITNA RIVER
PROGRESSION OF ICE
FRONT &ZERO DEGREE ISOTHERM
DIAGRAM OF FISH STREAM CROSSING
::'--..
~~~.~
~.•.'---
"'\'"
'\,.
-.---PERPENDICULAR
TO STREAM ~--.~{=-----
BOTTOMLESS ARCH
j
1
j
]
I
]
(
I
l
1
!
.!
-\
1
1
j
j
1
FIGURE E.3.2.119
,
/r~~/$'
/),5'
~
w
W
I--en
~oa:a:om
c
w
I-«
I--...J-m«
J:wa:
o
C\I....
C\I
C')
w
W
II:
:::>
(!:J
u.
o
l{)
CO
0>
T""
oos:
Iiio
0::
:::::>oen
GABIO....BARRIER
CONCRETE
I'll----REBAR REINFORCING
ANCHOR
FLOW--..-
FLOW ___
1'1----REBAR ANCHOR
CONCRETe SILL
ROCI(SILL BARRIER
FLOW------~.....C4:~~~~~1~~-···__·_···_---------------_·_·~
NATURAL DEPTH OF FLOW
POOL AND WEIR STRUCTURE CREATION OF POOI.S BETWEEN BARRIERS
FISH PASSAGE MITIGATION UTILIZING BARRIERS
(
1
1
1
1
SOURCE:wce 1984a FIGURE E.3.2.121
(I
II
FLOW--
FLOW-POOL
PASSAGE REACH,---IO!
SIDE VIEW
PASSAGE REACH
0
0 0 0 0
0 0 POOL
(:)0 0 0
0
EXPOSED ROCKS
PLAN VIEW
TYPICAL PASSAGE REACH OF SLOUGH ALONG
MIDDLE SECTION OF THE SUSITNA RIVER
J
I.J T
PASSAGE
REACH
'..
FLOW
~
;f!fJ"t--WING DEFLECTOR WALLS
+-+--LARGE COBBLE FILL..
LARGE COBBLE FILL
WING DEFLECTOR
1 HEIGHI'OF MAXIMUM SLOUGH DISCHARGE
~1111!~'5i~:l:hL._-L.---I1_.l..1---II_LI--l..~--J4-'
ROCK GABION CHANNEL
PLAN VIEW
WING DE FEelOR
MOD.IFYING CHANNEL WID.TH
SOURCE:WCC 1985b FIGURE E.3.2.122
PLAN VIEW
.....__SUSITNA RIVER MAINSTEM
J
j
]
]
J
1
.J
L=LENGTH OF BERM
GRAVEL AND
COBBLE FILL LARGE ROCK FACING
CROSS SECTIONAL VIEW
OVERTOPPING PREVENTION MITIGATION
BY INCREASING BERM HEIGHT
j
1
1
..I
I
J
J
J
.\
SOURCE:wee 1984a FIGURE E.3.2.123
L-'-'--'
HIGHr
RELATIVE UTILI ZATION OF SLOUGHS
I LOW
fREQUENCY OF WINTER OVERTOPPING
~
FREQUENCY Of WINTER OVERTOPPING
iii
LOW HIGH
8ERM
CON STRUCTION,
--l
LOW HIGH
8ERM
CONSTRUCTION
I I I
MINOR MAJOR
SLOUGH SLOUGH SLOUGH SLOUGH SLOUGH SLOUGH
MODIFICATION MODifiCATION MODIF ICATION MODlfl CATION MODIFICATION MODIFICATION
~n ~n n ~
MINOR MAJOR MINOR MAIOR MINOR MAJOR MINOR MAJOR MINOR MAJOR MINOR MAJOR
I I I I I I I I I I I I
1 2 3 4 9 10 5 6 7 8 11 12
•THE SMALLER THE RANK VALUE AT A SITE,THE MORE COST-EffECTIVE
WOULD 8E MITIGATION WORK AT THE SITE.
fLOW CHART FOR RANKING SITES
FOR MITIGATION DECISION MAKING
SOURCE:wcb 1985b FIGURE E.3.2.124
................-..........
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....
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GOLD CREEK DISCHARGE=14.8 (x 10 3 ) - -
!
1
I ''i '.....'.Wl,!',GOLD CREE!k,DISCHARGE=32.3 (x 10
3
)
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120
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2 i 3 4 5 6 7 8,9 10 11 12 13 14
'MILES ABOVE MOUTH OF PORTAGE CREEK
,i ,
TOTAL GAS SATURATION -~t-AND·....···
NITROGEN SATURATION -+_.!-
OXYGEN SATURATION -+-;~
•INDICATE AREAS OF RA~ID!S
I
CO~CENTRA TIONS OF DIS.sOL VED GASES IN
SOURCE:ADF&G 1983m D.EJLU.CAb,lYON RAPIDS COMPI EX
,J ...'I '_~~,C_'_'•__FIGl,./J:l!;~E.3 •.2_.12..5
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