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Susitna‐Watana Hydroelectric Project Document
ARLIS Uniform Cover Page
Title:
Characterization and mapping of aquatic habitats, Study plan Section 9.9,
Study Completion Report SuWa 289
Author(s) – Personal:
Author(s) – Corporate:
R2 Resource Consultants, Inc.
AEA‐identified category, if specified:
November 2015; Study Completion and 2014/2015 Implementation Reports
AEA‐identified series, if specified:
Series (ARLIS‐assigned report number):
Susitna-Watana Hydroelectric Project document number 289
Existing numbers on document:
Published by:
[Anchorage : Alaska Energy Authority, 2015]
Date published:
October 2015
Published for:
Alaska Energy Authority
Date or date range of report:
Volume and/or Part numbers:
Study plan Section 9.9
Final or Draft status, as indicated:
Document type:
text with 103 maps
Pagination:
vii, 99, 55, 55 pages
Related works(s):
Pages added/changed by ARLIS:
Notes:
Contents:
[Main report]
Appendix A. Remote line mapping, 2012-2014
Appendix B. Upper and middle river mainstem surveys, 2013-2014
All reports in the Susitna‐Watana Hydroelectric Project Document series include an ARLIS‐
produced cover page and an ARLIS‐assigned number for uniformity and citability. All reports
are posted online at http://www.arlis.org/resources/susitna‐watana/
Susitna-Watana Hydroelectric Project
(FERC No. 14241)
Characterization and Mapping of Aquatic Habitats
Study Plan Section 9.9
Study Completion Report
Prepared for
Alaska Energy Authority
Prepared by
R2 Resource Consultants, Inc.
October 2015
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
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TABLE OF CONTENTS
1. Introduction ....................................................................................................................... 1
2. Study Objectives................................................................................................................ 1
3. Study Area ......................................................................................................................... 3
4. Methods .............................................................................................................................. 4
4.1. General Overview of Habitat Mapping Methods ...............................................4
4.1.1. Remote line mapping using Aerial Imagery ....................................5
4.1.2. Overview of Ground Mapping Survey Protocols ............................8
4.2. Upper River Habitat Mapping .........................................................................12
4.2.1. Tributaries in the Upper River .......................................................13
4.2.2. Mainstem habitats in the Upper River ...........................................14
4.2.3. Lakes within the Upper River Inundation Zone ............................16
4.2.4. Variances from the Study Plan ......................................................17
4.3. Middle River Habitat Mapping ........................................................................17
4.3.1. Tributaries in the Middle River ......................................................18
4.3.2. Mainstem Habitats in the Middle River .........................................18
4.3.3. Variances from the Study Plan ......................................................19
4.4. Lower River Habitat Mapping .........................................................................20
5. Results .............................................................................................................................. 21
5.1. Upper River ......................................................................................................21
5.1.1. Tributaries in the Upper River .......................................................21
5.1.2. Mainstem Habitats in the Upper River ..........................................23
5.1.3. Comparisons between remote and field habitat characterizations in
the Upper River ..............................................................................24
5.1.4. Lakes Within the Upper River Inundation Zone ............................24
5.2. Middle River ....................................................................................................25
5.2.1. Tributaries in the Middle River ......................................................25
5.2.2. Mainstem Habitats in the Middle River .........................................26
5.2.3. Comparisons between remote and field habitat characterizations in
the Middle River ............................................................................27
5.3. Lower River .....................................................................................................28
6. Discussion......................................................................................................................... 28
6.1. Study Coordination and Updates .....................................................................29
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7. Conclusion ....................................................................................................................... 29
8. Literature Cited .............................................................................................................. 31
9. Tables ............................................................................................................................... 33
10. Figures .............................................................................................................................. 90
LIST OF TABLES
Table 4.1.1. Nested and tiered habitat mapping units and categories for macrohabitats and
mainstem channel mesohabitats. ................................................................................................... 34
Table 4.1.2. Nested and tiered habitat mapping units and hydraulic categories used for tributary
mesohabitats. ................................................................................................................................. 36
Table 4.1-1. Upper River tributary table showing all tributary geomorphic reaches, gradient,
basin area, and survey status. ........................................................................................................ 37
Table 4.1-2. Middle River tributary geomorphic reaches selected for ground survey, gradient,
basin area, and survey year(s). ..................................................................................................... 38
Table 4.1-3. Tributary geomorphic reach mesohabitat frequency and composition derived from
videography 2012.......................................................................................................................... 39
Table 4.2-1. Number of randomly selected Upper and Middle River mainstem macrohabitats
survyed and total number of Focus Area mainstem macrohabtiats surveyed during 100 percent
ground survey coverage. ............................................................................................................... 40
Table 4.2-2. Lakes in the Upper River located within the inundation zone, and habitat metrics
obtained from the Project GIS database or measured in the field. ................................................ 41
Table 4.2-3. Range of mean daily flows at the USGS 15292000 Susitna River at Gold Creek real
time streamflow gage during ground surveys. .............................................................................. 42
Table 5.1-1. Sum of length (m) surveyed, and composition by length of mesohabitats in Upper
River tributaries. ........................................................................................................................... 43
Table 5.1-2. Mean (±SD) percent gradient of mesohabitats in Upper River tributaries. .............. 44
Table 5.1-3. Mean (±SD) bankfull width (m) of mesohabitats in Upper River tributaries. ......... 45
Table 5.1-4. Mean (±SD) wetted width (m) of mesohabitats in Upper River tributaries. ............ 46
Table 5.1-5. Mean (±SD) bankfull depth (m) of mesohabitats in Upper River tributaries. .......... 47
Table 5.1-6. Mean (±SD) thalweg depth (m) of mesohabitats in Upper River tributaries. .......... 48
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Table 5.1-7. Mean (±SD) max pool and crest depths (m) of Beaver Pond and Pool mesohabitats
in Upper River tributaries. ............................................................................................................ 49
Table 5.1-8. Mean (±SD) percent erosion along mesohabitat units in Upper River tributaries. .. 50
Table 5.1-9. Mean (±SD) percent undercut banks along mesohabitat units in Upper River
tributaries. ..................................................................................................................................... 51
Table 5.1-10. Mean (±SD) LWD count in mesohabitat units of Upper River tributaries. ........... 52
Table 5.1-11. Mean (±SD) percent bedrock substrate in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 53
Table 5.1-12. Mean (±SD) percent boulder substrate in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 54
Table 5.1-13. Mean (±SD) percent cobble substrate in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 55
Table 5.1-14. Mean (±SD) percent gravel substrate in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 56
Table 5.1-15. Mean (±SD) percent and and silt substrate in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 57
Table 5.1-16. Mean (±SD) percent organic substrate in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 58
Table 5.1-17. Mean (±SD) percent instream cover in mesohabitat units of Upper River
tributaries. ..................................................................................................................................... 59
Table 5.1-18. Sum of length (m) surveyed and composition by length of riparian cover types
along Upper River tributaries........................................................................................................ 60
Table 5.1-19. Sample sizes and mean and standard deviation (sd) of mesohabitat length
measurements in meters made among geomorphic reaches by macrohabitat in mainstem habitats
surveyed. ....................................................................................................................................... 61
Table 5.1-20. Sample sizes and mean and standard deviation (sd) of mesohabitat length
measurements in meters made among geomorphic reaches by macrohabitat in Middle River
Focus Area mainstem habitats surveyed. ...................................................................................... 62
Table 5.1-21. Sample sizes and mean and standard deviation (sd) of mesohabitat percent gradient
measurements made among geomorphic reaches by macrohabitat in Upper River and Middle
River mainstem habitats surveyed. ............................................................................................... 63
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Table 5.1-22. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat Bankfull
Width in meters made among geomorphic reaches by macrohabitat in Upper River and Middle
River mainstem habitats surveyed. ............................................................................................... 64
Table 5.1-23. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat wetted
width in meters made among geomorphic reaches by macrohabitat in Upper River and Middle
River mainstem habitats surveyed. ............................................................................................... 65
Table 5.1-24. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat Bankfull
Depth in meters made among geomorphic reaches by macrohabitat in Upper River and Middle
River mainstem habitats surveyed. ............................................................................................... 66
Table 5.1-25. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat thalweg
depth in meters made among geomorphic reaches by macrohabitat in Upper River and Middle
River mainstem habitats surveyed. ............................................................................................... 67
Table 5.1-26. Sample sizes (n) and mean and standard deviation (sd) of maximum pool depth in
meters among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem
habitats surveyed. .......................................................................................................................... 68
Table 5.1-27. Sample sizes (n) and mean and standard deviation (sd) of percent erosion along
mesohabitat units in Upper River and Middle River mainstem habitats surveyed by macrohabitat.
....................................................................................................................................................... 69
Table 5.1-28. Sample sizes (n) and mean and standard deviation (sd) of percent undercut banks
along mesohabitat units in Upper River and Middle River mainstem habitats surveyed by
macrohabitat. ................................................................................................................................. 70
Table 5.1-29. Sample sizes (n) and mean and standard deviation (sd) of large woody debris
counts within mesohabitat units in mainstem habitats. ................................................................. 71
Table 5.2-1. Sum of length (m) surveyed, and composition by length of mesohabitats in Middle
River tributaries. ........................................................................................................................... 72
Table 5.2-2. Mean (±SD) percent gradient of mesohabitats in Middle River tributaries. ............ 73
Table 5.2-3. Mean (±SD) bankfull width (m) of mesohabitats in Middle River tributaries. ........ 74
Table 5.2-4. Mean (±SD) wetted width (m) of mesohabitats in Middle River tributaries. .......... 75
Table 5.2-5. Mean (±SD) bankfull depth (m) of mesohabitats in Middle River tributaries. ........ 76
Table 5.2-6. Mean (±SD) thalweg depth (m) of mesohabitats in Middle River tributaries. ......... 77
Table 5.2-7. Mean (±SD) max pool and crest depths (m) of Beaver Pond and Pool mesohabitats
in Middle River tributaries. ........................................................................................................... 78
Table 5.2-8. Mean (±SD) percent erosion along mesohabitat units in Middle River tributaries. . 79
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Table 5.2-9. Mean (±SD) percent undercut banks along mesohabitat units in Middle River
tributaries. ..................................................................................................................................... 80
Table 5.2-10. Mean (±SD) LWD count in mesohabitat units of Middle River tributaries. .......... 81
Table 5.2-11. Mean (±SD) percent bedrock substrate in mesohabitat units of Middle River
tributaries. ..................................................................................................................................... 82
Table 5.2-12. Mean (±SD) percent boulder substrate in mesohabitat units of Middle River
tributaries. ..................................................................................................................................... 83
Table 5.2-13. Mean (±SD) percent cobble substrate in mesohabitat units of Middle River
tributaries. ..................................................................................................................................... 84
Table 5.2-14. Mean (±SD) percent gravel substrate in mesohabitat units of Middle River
tributaries. ..................................................................................................................................... 85
Table 5.2-15. Mean (±SD) percent and and silt substrate in mesohabitat units of Middle r River
tributaries. ..................................................................................................................................... 86
Table 5.2-16. Mean (±SD) percent organic substrate in mesohabitat units of Middle River
tributaries. ..................................................................................................................................... 87
Table 5.2-17. Mean (±SD) percent instream cover in mesohabitat units of Middle River
tributaries. ..................................................................................................................................... 88
Table 5.2-18. Sum of length (m) surveyed and composition by length of riparian cover types
along Middle River tributaries. ..................................................................................................... 89
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LIST OF FIGURES
Figure 3-1. Aquatic habitat characterization and mapping study area. ......................................... 91
Figure 4.1-1 Susitna River flows in 2013 and 2014 with the timing of field surveys
superimposed. ............................................................................................................................... 92
Figure 4.1-2. Map of Upper River tributaries with tributaries selected for field-surveys identified.
....................................................................................................................................................... 93
Figure 4.2-1 Map of Upper River lakes within the potential zone of reservoir inundation. ......... 94
Figure 4.4-1 Aerial video capture of the Lower Susitna River mainstem showing highly complex
braided channels characteristic of main channel habitats in this river section. ............................ 95
Figure 5.1-1. Upper River tributary mesohabitat frequencies from 2012 videographic surveys. 96
Figure 5.1-2. Upper River tributary mesohabitat frequencies from 2013-2014 ground surveys. . 97
Figure 5.1-3. 2014 dissolved oxygen profiles in Lakes 1-12. ....................................................... 98
Figure 5.1-4. 2014 temperature profiles in Lakes 1-12. ............................................................... 99
APPENDICES
Appendix A: Remote Line Mapping 2012-2014
Appendix B: Ground Survey Maps, 2013-2014
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LIST OF ACRONYMS, ABBREVIATIONS, AND DEFINITIONS
Abbreviation Definition
AEA Alaska Energy Authority
ARRC Alaska Railroad Corporation
BFD measured bankfull depth
BFW measured or estimated bankfull width
ºC degrees Celsius
CFR Code of Federal Regulations
cfs cubic feet per second
CIRWG Cook Inlet Region Working Group
DO dissolved oxygen
FA Focus Area
FDA Fish Distribution and Abundance Studies (Studies in RSP Sections 9.5 and 9.6)
FERC Federal Energy Regulatory Commission
ft Feet
GIS Geographic Information System
GPS Global Positioning System
IFSAR Interferometric Synthetic Aperture Radar
ILP Integrated Licensing Process
ISR Initial Study Report
LB left bank – looking downstream
Level 3 mainstem and tributary macrohabitat
Level 4 mainstem and tributary mesohabitat
LiDAR Light Detection and Ranging. An optical remote sensing technology.
LWD large woody debris
m meter(s)
mg/L milligrams per liter
mi mile(s)
MSB Matanuska-Susitna Borough
NHD National Hydrography Database
PRM Project river mile
RB right bank – looking downstream
RM river mile(s) referencing those of the 1980s APA Project
RSP Revised Study Plan
SD standard deviation
SPD Study Plan Determination
TWG Technical Workgroup
USFS United States Forest Service
USGS United States Geological Survey
yd yard
ZHI zone of hydrologic influence
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1. INTRODUCTION
This Characterization and Mapping of Aquatic Habitats, Section 9.9 of the Revised Study Plan
(RSP) approved by the Federal Energy Regulatory Commission (FERC or Commission) for the
Susitna-Watana Hydroelectric Project, FERC Project No. 14241, focuses on describing the
aquatic habitats of the Susitna River using a specific hierarchical and nested classification system
based on historic and current data.
A summary of the development of this study, together with the Alaska Energy Authority’s
(AEA) implementation of it through the 2013 study season, appears in Part A, Section 1 of the
Initial Study Report (ISR) filed with FERC in June 2014. As required under FERC’s regulations
for the Integrated Licensing Process (ILP), the ISR describes AEA’s “overall progress in
implementing the study plan and schedule and the data collected, including an explanation of any
variance from the study plan and schedule.” (18 CFR 5.15(c)(1)).
Since filing the ISR in June 2014, AEA has continued to implement the FERC-approved plan for
the Characterization and Mapping of Aquatic Habitats. For example:
AEA completed ground-truthing surveys in mainstem habitats of the Upper River and
Middle River including 100 percent coverage of mesohabitat mapping within Focus
Areas.
AEA completed ground surveys of selected Upper and Middle River tributaries.
AEA collected habitat information for the 12 lakes identified within the potential
reservoir inundation zone.
On September 17, 2014, AEA filed the 2013 and 2014 Aquatic Habitat Mapping Field
Season Completion Progress Technical Memorandum.
On October 15, 2014, AEA held an ISR meeting for the Characterization and Mapping of
Aquatic Habitats.
On November 14, 2014, AEA filed errata to Initial Study Report Part A - Appendix A,
Remote Line Mapping, 2012. This map book replaced the version published on June 3,
2014 with the Study 9.9 Initial Study Report.
In furtherance of the next round of ISR meetings and FERC’s SPD expected in 2016, this report
contains a comprehensive discussion of results of the Characterization and Mapping of Aquatic
Habitats from the beginning of AEA’s study program in 2012, through the end of calendar year
2014. It describes the methods and results of the Characterization and Mapping of Aquatic
Habitats, and explains how all Study Objectives set forth in the Commission-approved Study
Plan have been met. Accordingly, with this report, AEA has now completed all field work, data
collection, data analysis, and reporting for this study.
2. STUDY OBJECTIVES
The study objectives were established in the Study Plan (RSP Section 9.9.2) and are described
below.
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Upper River Habitats:
1. Characterize and map Upper River tributary and lake habitats for the purpose of
evaluating the potential loss or gain in available fluvial and lacustrine habitat that
may result from dam construction and inundation by the reservoir.
2. Characterize and map Upper River tributary and lake habitats for the purposes of
informing other studies including Fish Distribution and Abundance in the Upper
Susitna River (Study 9.5) and River Productivity (Study 9.8).
3. Characterize and map the Upper River mainstem (understood hereafter to
encompass both main channel and off-channel habitats) upstream from the
Watana dam site to the confluence with the Oshetna River:
i. To provide baseline data for the purpose of evaluating the potential loss
or gain in accessible available fluvial and lacustrine habitat that may
result from dam construction and inundation by the reservoir.
ii. To inform other studies including Fish Distribution and Abundance in
the Upper Susitna River (Study 9.5), River Productivity (Study 9.8), and
Future Watana Reservoir Fish Community and Risk of Entrainment
(Study 9.10).
Middle River Habitats:
1. Characterize and map the Middle River mainstem from the Chulitna River confluence
to the proposed Watana Dam site, including tributaries within the zone of hydrologic
influence (ZHI) and the Focus Areas:
i. To provide baseline data for the purpose of evaluating the potential loss
or gain in accessible available fluvial habitat that may result from flow
regulation below the proposed Watana Dam.
ii. To inform other studies including Fish Distribution and Abundance in
the Middle and Lower Susitna River (Study 9.6), River Productivity
(Study 9.8), and Instream Flow (Study 8.5).
Lower River Habitats:
1. Characterize and map the Lower River mainstem from the upper extent of tidal
influence upstream to the Three Rivers Confluence:
i. To provide baseline data for the purpose of evaluating the potential loss or
gain in available fluvial habitat that may result from flow regulation below the
proposed Watana Dam.
ii. To inform other studies including Fish Distribution and Abundance in the
Middle and Lower Susitna River ( Study 9.6), River Productivity (Study 9.8),
and Instream Flow (Study 8.5).
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3. STUDY AREA
As established by the Study Plan (RSP Section 9.9.4) and modified as described below, the study
area encompasses the mainstem Susitna River from the Oshetna River confluence at PRM 235.1
downstream to the upper extent of tidal influence. The mainstem study area is divided according
to geomorphic/hydrologic river segments; the Upper River, Middle River, and Lower River (see
Figure 3-1). The study area also encompasses tributaries in the Upper and Middle River. Note
that the study area for selected Upper River tributaries has been modified in accordance with the
Characterization and Mapping of Aquatic Habitats Technical Memorandum which was reviewed
by the agencies and filed with FERC on July 16, 2013 (HDR 2013).
The study area for habitat mapping and characterization is as follows:
Upper River
o Tributaries: For selected streams in watersheds known to support Chinook
salmon, the habitat mapping study area extends up to 3,000 ft elevation, unless a
permanent impassable barrier exists between 2,200 and 3,000 ft elevation. If a
barrier exists within this range, surveys will stop at the barrier. In watersheds not
known to support Chinook salmon, the habitat mapping study area will terminate
at 2,200 ft elevation regardless of the presence of a barrier below this elevation.
o Mainstem: Mainstem habitats from the Oshetna River confluence at PRM 235.1
to the proposed dam site at PRM 187.1 and focused on habitats within the
inundation zone of the proposed reservoir.
o Lakes: Lakes within the proposed reservoir inundation zone.
Middle River:
o For selected tributaries above Devils Canyon known to support Chinook salmon,
the study area extends up to 3,000 ft elevation or the first impassable barrier,
whichever is less.
o For all other selected tributaries in the Middle River, the study area extends from
the confluence with the mainstem or off-channel up to the upper limit of the zone
of hydrologic influence (ZHI).
o Mainstem habitats of the Susitna River from PRM 187.1 downstream to the
Chulitna River confluence at PRM 102.4.
Lower River:
o The Lower Susitna River from PRM 102.4 to the upper extent of tidal influence.1
1 The Study Plan (RSP Section 9.9.4) provided that AEA would consider the study area for the
Lower River segment to extend downstream to the upper extent of tidal influence. AEA adjusted
the study area for the Lower River segment to extend downstream to PRM 3.3. Mapping and
characterization in the Lower River segment has been completed (see Section 4.4) using
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4. METHODS
This section provides an updated description of the methods relied upon to meet the Study Plan
objectives. These methods are cumulative for 2012 through 2014 and include methods reported
in the ISR Section 4. To the extent that the methods have varied from the method described in
the Study Plan, those variances are described below.
4.1. General Overview of Habitat Mapping Methods
Habitat mapping methods were consistent during study activities in 2013 and 2014. This
overview is largely unchanged from ISR Section 4.1 with the exception of Section 4.1.2.4, which
has been updated to describe the flow conditions during 2014 field surveys.
The Susitna River from the Oshetna River to its mouth (Upper, Middle and Lower River
segments combined) includes 235 miles of river and substantially more stream distance when the
lengths of side channels, braided channels, and sloughs are included. Ground-based habitat data
collection along the entire river is impractical due to the complexity of channel plan form, the
linear extent, and the remoteness of the river. For these reasons, an analysis of aerial imagery
was combined with ground-based habitat data collection covering a representative proportion of
river habitats to form a habitat characterization of the river. In addition, the ten Focus Areas that
were identified and described in the Technical Memorandum: Adjustments to Middle River
Focus Areas (R2 Resource Consultants 2013a) were targeted for 100 percent mapping coverage
using both aerial imagery and ground-based surveys. This combination of methods allowed for
optimum spatial coverage of river habitats in concert with efficient collection of detailed data at
selected habitats. Habitat characterization methods were tailored to accommodate variations in
channel size and overall stream length. This approach used various mapping methods and tools
to meet multiple study objectives and provides the best possible coverage and characterization of
river habitats in a large, complex river basin.
Because potential Project effects are different among geomorphic segments of the river, habitat
mapping methods were differentiated within the study area first by major geomorphic segment
(Upper River, Middle River, and Lower River). Methods were further differentiated by
tributary, main channel, off-channel and lake habitat to accommodate the major differences in
morphology and hydrology among these habitats. Habitat data collected in this study used the
Susitna-Watana Hydroelectric Project habitat classification system (Table 4.1-1) developed
during the 2012 study design and planning process and modified by FERC’s April 2013 SPD
recommendations as well as standard protocols outlined in the USFS Aquatic Habitat Surveys
Protocol (USFS 2001). When flow levels were too low to evaluate mesohabitat type,
mesohabitat units were characterized by the flow levels described in Section 4.1.2.2 (i.e. dry,
puddled).
information from the Geomorphology Study (ISR 6.5). This change in study area boundaries for
the Lower River will allow AEA to better meet the objective of mapping and characterizing
habitat in this river segment by aligning boundary descriptions between these studies.
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4.1.1. Remote line mapping using Aerial Imagery
During the 2012 remote line mapping effort, data derived from aerial imagery were
supplemented with information from video mapping to generate a geospatial database within a
GIS (geographic information systems) framework. The remote line mapping effort used high
resolution elevation data and aerial imagery for 3,680 square miles of the Matanuska-Susitna
Borough (MSB) collected as part of the MSB LiDAR and Imagery Project. Aerial imagery was
obtained over five days between May 25, 2011 and August 16, 2011. Flows for the majority of
these flights - as measured at the Gold Creek USGS gage (PRM 140) – ranged between 16,700
and 18,300 cfs with one day occurring at a high flow of 30,600 cfs; videography was collected
from September 7-11, 2012. During the video collection, mean daily discharge from Gold Creek
steadily declined from 16,500 cfs on September 7 to 10,800 cfs on September 11, 2012. The
methods for video surveys are comprehensively described in RSP Section 9.9.5.4 and technical
memoranda (HDR Alaska, Inc. 2013b; R2 Resource Consultants, Inc. 2013b). Remote line
mapping of habitats in the study area was completed using a hierarchically-nested habitat typing
system that was adapted to the identification levels deemed feasible based on the available aerial
imagery (Table 4.1-1). The habitat classification hierarchy was composed of four levels
representing: (1) major hydrologic segment; (2) geomorphic reach (RSP Section 6.5.4.1.2.2 and
RSP Table 6.5-1); (3) macrohabitat type (Table 4.1-1); and (4) mesohabitat type (Mainstem,
Table 4.1-1; Tributary, Table 4.1-2).
For remote line mapping in the mainstem of the river, all main channel habitats were identified
to Level 4 mesohabitat type (riffle, pool, run, etc.). Off-channel habitat (which includes side and
upland sloughs) and most tributaries were classified to Level 3 (macrohabitat). These units were
not classified into mesohabitats in the remote line-mapping due to the lack of resolution of aerial
imagery and the confounding presence of shadows or riparian cover. During the 2013 and 2014
field efforts, off-channel habitats were specifically targeted to characterize a subsample of these
habitats to the level of mesohabitat (Sections 4.2.2 and 4.3.2). A subset of 10 primary and 3
secondary tributaries were habitat typed to Level 4 (mesohabitat) using the results of the 2012
videography as discussed in Section 4.1.1.2 and further described in Appendix 2 of the Fish
Distribution and Abundance Implementation Plan (R2 Resource Consultants 2013b). An
additional 15 smaller primary and secondary tributaries were identified and ground surveyed
following the FERC April 1 SPD and in consultation with the TWG via agency review of the
Technical Memorandum: Characterization and Mapping of Aquatic Habitats (HDR 2013) during
July of 2013.
The methods used to compare remote (2012) and field mapping data (2013 and 2014) are
presented in sections 4.2.2.1 and 4.3.2.1 and the results of that verification of aerial imagery and
video typing are presented in sections 5.2.2.1 and 5.3.2.1.
A mapbook presenting the 2012 remote line mapping effort was included as Appendix A to Part
A of the ISR. During the ISR meeting, it was identified that the data query used to build the
maps inadvertently did not include side slough habitat in the reaches between MR-1 and UR-5
and side sloughs were not depicted on Appendix A maps 1 through 21. On November 14, 2014,
AEA filed errata with an updated mapbook that was corrected by using the same GIS files to
produce maps with all layers turned on; thus including side sloughs throughout the study area.
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4.1.1.1. GIS Habitat Mapping
As described in ISR Section 4.1.1.1, in 2012 a linear network was created in GIS by drawing
vector-lines (segments) along the stream channel center line as viewed by aerial imagery or
LiDAR. Mainstem habitats were uniquely identified and delineated into segments. Divided
channels were assigned multiple segments. The lengths of the segments were based on
mesohabitat classifications for the main channel and macrohabitat classifications for off-channel
habitats (Table 4.1-1). Each individual vector line segment in the GIS was thus associated with a
length and a hierarchical-tiered habitat classification. Not all lines were connected into a
contiguous or flow-based network. Note that since there could be multiple macrohabitat types
laterally distributed within the floodplain, the total length of habitat identified during remote line
mapping could have been considerably longer than the length of each geomorphic reach.
While mapping the mainstem in GIS, tributaries also were delineated in the aerial imagery up to
0.5 mi from the centerline of the main channel or off-channel confluence. Tributaries were
differentiated from upland sloughs based on their gradient characteristics and whether they
originated above the floodplain. The exact locations of some tributary segments were difficult to
determine using the available imagery in heavily forested areas. These locations were estimated
based on visual cues in the canopy. Tributary mouths were mapped using a single line segment
showing the length of the wetted area of the tributary mouth that extended from the vegetation
line out to the edge of the gravel bank. In some of the larger tributaries, the mouth habitat was
extended inland beyond the vegetation line based on visible habitat breaks between the tributary
channel and the alluvial gravel areas at the mouth.
Within the Upper River tributaries, macrohabitats were mapped from aerial imagery where
possible. Matanuska-Susitna Borough LiDAR and imagery were available for the lower extent
of many tributaries. However, overhanging vegetation, shadows and other environmental
conditions limited characterization of mesohabitats from these sources. In higher elevations
within tributaries or within small secondary or tertiary tributaries, mesohabitat characterization
was not possible from aerial imagery due to a lack of high resolution photography. A subset of
17 tributaries was thus selected for mesohabitat typing by videography as described in Section
4.1.1.2.
Aerial imagery was used to further classify mainstem habitat into mesohabitats (Table 4.1.1).
Aerial still imagery was viewed at a range of scales from 1:1,000 to 1:12,000 and 2012
videography was referenced as needed. All habitat units were identified using a mid-channel
line, which was measured to provide habitat length (HDR Alaska, Inc. 2013a, ISR Appendix B).
In channels that were only partially inundated or where water was present in sloughs, the line
segments followed the wet areas. AEA has estimated macro- and mesohabitat frequency within
main channel, off-channel and tributary study areas based on these data (HDR Alaska 2013a,
ISR Appendix B).
Main channel macrohabitats in the Susitna River were classified as single main channel when
only a single dominant channel was present; split main channels when the flow was dispersed
into two relatively evenly sized channels where the bar or island separating the channels was
typically not vegetated; and multiple split main channels when the main channel split into three
or more separate channels each carrying a significant portion of the flow.
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Side channels were completely inundated with turbid water (or contained portions that held
turbid water), connected at both upstream and downstream ends to the main channel, and flowing
around a permanently vegetated island and carried less than 10 percent of the main channel flow.
The dry portions of the channel were delineated based on substrate and a lack of any vegetation,
indicating that water periodically inundated the channel during higher flow periods. The
distance that the side channel line segments extended into the main channel was determined by
an estimation of the continuation of the vegetated or high water shoreline on either side of the
mouth of the side channel. The presence of clear or turbid water was used as a main indicator to
differentiate between sloughs and side channels.
Side sloughs had clear water and were only connected at the top of the channel to the main
channel at high flows. These areas could be partially dry but showed evidence that they were
inundated regularly during high flows by lack of permanent vegetation. Upland sloughs had
similar characteristics in that the water was relatively clear, but these were not open to the main
channel at both ends as indicated by the presence of vegetation in the area between the upstream
end of the slough and the main channel.
Mesohabitats were classified from interpretation of both the GIS imagery and aerial video.
Mapping main channel habitats to the mesohabitat level from remote imagery was challenging
for certain habitat types that included differentiating run and glide habitat and identifying pool
habitat. Riffles were distinguished from areas of wind waves or standing waves by the presence
of white water and protruding boulders in the area that indicated the water was relatively shallow
and passed over cobbles and boulders. Whitewater in a reach was classified as a run if only one
or two protruding boulders were producing isolated areas of turbulence. Run and glide habitat
was closely examined through aerial stills and videography to make a professional judgment of
the habitat type; however, wind-waves and glare can confound the typing of these habitats. Pool
habitat required identifying a hydraulic control and was only found in the Devils Canyon area,
where the control was very obvious. Small, less obvious pools may have not been identified
from this methodology.
The exact location of habitat boundaries, such as the boundary between a riffle and run/glide,
often required professional judgment on the part of the mapper. Due to lack of resolution in the
aerial imagery and shadows along the left bank of the river, some habitat features such as
tributary mouths were confirmed by using aerial video as a secondary reference (Section
4.1.1.2). Aerial video was also used to confirm the extent of vegetation on more permanent
gravel bars that showed some vegetation, which was sometimes not evident in the aerial imagery.
If the aerial video indicated a bar had vegetation on it, but vegetation was not evident in the
aerial imagery, the island was considered vegetated and this criteria was used to aid in separating
the main channel line segment into a main channel segment containing the dominant portion of
flow and a side channel segment containing less than ten percent of flow around the island.
Additional details on methods associated with the creation of the remote line mapping habitat
characterizations are available in previously filed technical memos (HDR Alaska, Inc. 2013a;
ISR Appendix B).
4.1.1.2. Aerial Video Data Collection and Analysis
As described in ISR Section 4.1.1.2, low altitude aerial video was collected in 2012 for the
Upper River from PRM 187.1 to PRM 235.4, the Middle River from PRM 102.4 to PRM 187.1,
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and a short section of the Lower River from PRM 68.0 to PRM 83.5. The study area for the
tributary component of the 2012 Aerial Video Habitat Mapping (HDR Alaska, Inc. 2013b, R2
Resource Consultants, Inc. 2013b) included 16 tributary streams above Devils Canyon upstream
to and including the Oshetna River. All tributaries above Devils Canyon with documented
Chinook salmon presence were included within the videography study area (Tables 4.1-3 and
4.1-4).
Because habitat delineation within tributaries was not always possible from remote imagery, a
mesohabitat frequency analysis was completed for a subset of habitat in 16 videotaped tributaries
(Table 4.1-3) using a systematic random sample of the video recording as described in the Study
Plan (RSP Section 9.9.5.3.1). Videography collected in the Upper and Middle River mainstem
was used as supplemental information in support of habitat characterization from remote
imagery.
Aerial video was collected over a period of six days from September 7 to September 12, 2012
during optimal conditions that preceded a major flooding of the Susitna River in mid-September.
Videotaping of main channel and off-channel habitats of the Susitna River and tributaries was
scheduled in early September 2012 to coincide with late summer base-flow conditions, high
water clarity, leaf drop and the possibility of a sustained high pressure, clear weather window.
These conditions were achieved (HDR Alaska, Inc. 2013a).
Aerial video coverage within the study tributaries generally extended from the confluence with
the Susitna River, or with the primary tributary, upstream to an elevation of approximately 3,000
ft. In tributaries in the Upper River not known to support Chinook salmon, video mapping
terminated at approximately 2,200 ft elevation. For non-Chinook tributaries in the Middle River
above Devils Canyon, video mapping terminated at the first anadromous barrier. Devil Creek, a
Middle River tributary in Devils Canyon upstream of Impediment 3, was videotaped upstream to
the impassable barrier at approximately RM 2.2.
Within each tributary reach, (as delineated in Section 4.1.2.1.2), mesohabitat frequency analysis
from video was used to identify primary mesohabitat types, defined as those comprising more
than 10 percent of the total frequency of mesohabitat types observed by reach (Table 4.1-5).
These primary mesohabitats were then used to set sampling targets for the ground-mapping
exercise within identified tributaries (Section 4.2.1).
Additional details of videography methods, analysis and interpretation are included in Appendix
2 of the Fish Distribution and Abundance Implementation Plan entitled Initial Results Aerial
Video Habitat Mapping of Susitna River Tributaries from the Upper Extent of Devils Canyon to
the Oshetna River (R2 Resource Consultants, Inc. 2013b).
4.1.2. Overview of Ground Mapping Survey Protocols
Ground mapping survey protocols were consistently applied in 2013 and 3014. As described in
ISR Section 4.1.2, the intent of the ground mapping effort was to provide mesohabitat
classifications in habitats that were difficult to survey using remote line mapping methods (e.g.
tributaries and off-channel habitats), to provide detailed habitat characterization of Focus Areas,
and to ground-truth a random sample of macro and mesohabitat classifications from the remote
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line mapping database. Field surveys used the same hierarchically-nested habitat typing system
developed for use during the remote line mapping exercise (Tables 4.1-1 and 4.1-2). This
overview describes the general methods applied to habitat mapping and surveys overall. River
segment-specific variations in methods are presented in Sections 4.2, 4.3, and 4.4 for the Upper
River, Middle River and Lower River, respectively.
The methods used to compare remote (2012) and ground mapping data (2013 and 2014) are
presented in sections 4.2.2.1 and 4.3.2.1 and the results of that verification of aerial imagery and
video typing are presented in sections 5.2.2.1 and 5.3.2.1.
4.1.2.1. Geomorphic Reach Delineation
4.1.2.1.1. Mainstem Susitna River
The Susitna River was categorized into Geomorphic Reaches as part of the Geomorphology
Study (Study 6.5) and consisted of six reaches for the Upper River Segment (UR-1 through UR-
6), eight reaches for the Middle River Segment (MR-1 through MR-8), and six reaches for the
Lower River Segment (LR-1 through LR-6) (Section 5.1.2 in ISR Study 6.5 and Figure 3-1).
The geomorphic reach breaks were based in part on the following five factors: 1) planform type
(single channel, island/side channel, braided); 2) constraints; 3) confinement (approximate extent
of floodplain, off-channel features); 4) gradient; and 5) bed materials. Details of geomorphic
reach delineation are provided in the Geomorphic Reach Delineation and Characterization,
Upper, Middle, and Lower Susitna River Segments 2015 Updated Technical Memorandum
(TetraTech 2015)
4.1.2.1.2. Tributaries
As described in ISR Section 4.1.2.1.2, tributaries were segmented into geomorphic reaches using
desktop tools including IFSAR topographic contour data, U.S. Geological Survey (USGS)
topographic maps, aerial video, and information from reconnaissance flights. Reach breaks were
identified in 2013 using the following criteria:
1. Gradient reach break: a significant transition in slope of valley or channel;
2. Confinement reach break: a significant transition in bankfull width:valley width or
wetted:bankfull width ratios;
3. Hydrologic reach break: a tributary confluence where the tributary appeared to contribute
more than 10 percent of total flow to the main channel or parent tributary. A segment
boundary was not placed where downstream channel characteristics were primarily
controlled by bedrock rather than fluvial processes.
4.1.2.2. Field Methods
Field methods described in ISR Section 4.1.2.2 were implemented during surveys in both 2013
and 2014. Habitat metrics were collected using a modified U.S. Department of Agriculture,
Forest Service (USFS) Tier I through Tier III stream habitat survey protocol (USFS 2001).
Some of the habitat metrics listed in the USFS protocol assume that the stream being surveyed is
wadeable; however, many of the tributaries and mainstem habitat units selected for ground
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surveys were only wadeable along stream margins. Modifications were made to accommodate
non-wadeable stream reaches.
The following habitat metrics were collected for each selected tributary geomorphic reach, and
for each mainstem habitat unit:
Habitat Metrics
Mesohabitat unit type (Tables 4.1.1 and 4.1.2)
GPS location of channel measurements
Measured or estimated gradient
Measured unit length (range finder or remote using GIS)
Measured or estimated bankfull width (BFW) (three measurements per unit)
Measured average wetted width (three measurements per unit)
Measured bankfull depth (BFD) of unit (three measurements per unit)
Measured or estimated wetted maximum depth (thalweg) (three measurements per unit)
Estimated percent substrate composition within wetted width of unit
If pool, estimated or measured maximum depth
If pool, estimated or measured pool crest depth
If pool, identified structural feature forming the pool
Large woody debris (LWD) count within wetted width of unit
Estimated percent undercut, each bank in unit
Estimated percent erosion, each bank in unit
Type and percent in-stream cover in unit
Estimated percent riparian vegetation cover in unit
Dominant riparian vegetation type for each unit
Photograph of each unit
Field surveys were conducted by two- or three-person survey crews. Each survey crew consisted
of a qualified lead biologist and field technician(s). To the extent possible, field surveys were
conducted at flows similar to those recorded during the capture of aerial video and reference
photographs (Figure 4.1-1).
Mainstem survey start and end points for the randomly selected macro- and mesohabitat units
were determined from GIS waypoints obtained from the GIS database prior to field efforts
commencing (Sections 4.2.2 and 4.3.2). Habitat units within mainstem and tributary surveys
were sequentially numbered as encountered from downstream to upstream.
Tributary ground survey start and end points were based on those detailed for video-mapping in
tributaries (Section 4.1.1.2). Accordingly, tributary ground survey reaches originated in the
lowest geomorphic reach of the tributary just upstream of the ordinary high water line of the
mainstem Susitna and progressed in an upstream direction. In Upper River tributaries, ground
surveys ended at 3,000 ft or if a permanent impassable barrier was encountered upstream of the
2,200-ft elevation point (Table 4.1-3). Permanent impassable barriers encountered downstream
from the 2,200-ft elevation point were documented and barrier measurements were taken. In
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Middle River tributaries above Devils Canyon, ground surveys also ended at 3,000 ft or if a
permanent impassable barrier was encountered, whichever came first (Table 4.1-3) where
permanent impassable barriers were encountered these were documented and barrier
measurements were taken and the survey continued. If no Chinook presence was documented,
surveys ended at the upper extent of the zone of hydrologic influence (ZHI) of potential project
operations. For tributary surveys in the Middle River below Devils Canyon, surveys were
conducted within the length of stream within the ZHI (Table 4.1-4).
When split or multiple split main channels were encountered in mainstem surveys, the channel
identified by the remote line was surveyed and the estimated percent of flow in that channel was
recorded. When split main channels were encountered in tributaries, both channels were
surveyed with the channel containing an estimated majority of flow categorized as primary, and
the other categorized as secondary. Mesohabitat units in the primary channel were categorized
as primary units and were numbered sequentially as part of the main tributary channel survey.
Mesohabitats within secondary channels were recorded separately. When multiple split main
channels were encountered in tributaries (more than two dominant channels), each channel was
photographed; however, only the primary and secondary channels were surveyed.
The Susitna River mean daily discharge was obtained from the nearest downstream USGS
stream gage for each field survey date. In addition, relative flow levels in each mesohabitat on
the day of the survey were estimated using the following qualitative categories:
Dry: No surface water visible,
Puddled: Series of isolated pools connected by surface trickle or visible subsurface flow
(e.g., wetted substrates),
Low Flow: Surface water flowing across 50 to 75 percent of the BFW,
Moderate Flow: Surface water flowing across 75 to 90 percent of the BFW,
High Flow: Stream flowing completely across BFW, but not at BFW.
4.1.2.3. Special Habitat Features
In the RSP, special habitat features were defined as tributaries, seeps, and springs that
contributed tributary or groundwater to the mainstem and temporary (e.g., subsurface flow,
perched debris jams, perched culverts) or permanent barriers to upstream fish migration.
Backwater habitats, beaver complexes and clearwater plumes were considered Level 3
macrohabitats during the development of the study plan but were subsequently re-assigned as
Level 4 mesohabitats (following the directive in the April 1, 2013 SPD). Accordingly,
backwaters, beaver complexes and clearwater plumes were also treated as special habitat features
and along with the features described above (Section 4.1.2.2), were specifically noted and
characterized when encountered in the course of general field survey efforts in 2013 and 2014.
Additional data pertinent to these features (e.g. width of the feature in addition to channel wetted
width) were noted on field forms. A GPS waypoint was recorded and a photograph taken of
each special feature.
For features classified as stream barriers only cursory information was collected under the
Habitat Mapping study, as most of the formalized barrier survey data are being collected under
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the Fish Passage Barrier Study (ISR Study 9.12). When a barrier was encountered, the following
information was recorded:
Barrier type (beaver dam, debris dam, vertical falls, chute/cascade, boulder, other),
Temporal nature (ephemeral or permanent),
Maximum height of falls or biggest single step if cascading,
Maximum depth of plunge pool,
Chute/cascade gradient and length,
Length of feature.
4.1.2.4. Mapping near reference flows
AEA implemented the methods as described in the Study Plan with the exception of the
variances described in ISR Part A Sections 4.2.4.3 and 4.3.3.3 and below in Sections 4.2.4.2 and
4.3.3.2. Flows in the Susitna River as measured at the Gold Creek gage were generally higher
than those recorded during videography and imagery used for remote line mapping although they
were within target upper flows established during operational planning to guide field efforts
(Figure 4.1-1). Field surveys in 2013 and 2014 were conducted in a roughly downstream to
upstream manner throughout the field season. During 2013, flows during surveys in Middle
River reaches were closer to target or reference flows than the Upper River surveys conducted in
the later portion of the field effort (Figure 4.1-1). Flows occurring during 2014 field surveys
were less variable than during the previous year, ranging from 17,930 to 23,800 cfs over the
majority of the survey period (Figure 4.1-1).
4.2. Upper River Habitat Mapping
AEA implemented the methods as described in the Study Plan with the exception of the
variances described in ISR Part A Section 4.2.4 and below in Section 4.2.4. Following
completion of the 2012 remote line mapping effort (Section 4.1.1), field surveys were conducted
to ground-truth Upper River habitat to the mesohabitat level in both 2013 and 2014 (Section
4.1.2). Due to the vast extent of the Upper River, sub-sampling during ground-truthing was
required. Ground surveys were planned for a total of 42 randomly selected mainstem
macrohabitat units (a target of 7 of each macrohabitat type), 42 single main channel mesohabitat
units, 25 tributaries within the proposed reservoir inundation zone, and three tributaries (two
primary, one secondary) located upstream of the inundation zone. The Upper River inundation
zone tributaries targeted for field surveying included 10 primary tributaries that were also
selected for fish distribution and abundance sampling and had been previously video surveyed
(Section 4.1.1.2) and 15 additional small primary and secondary tributaries selected in response
to the FERC April 2013 SPD and consultation with the TWG following review of the Technical
Memorandum: Characterization and Mapping of Aquatic Habitats (HDR 2013). The Upper
River tributaries selected and those surveyed during the 2013 and 2014 field seasons are listed in
Table 4.1-1.
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4.2.1. Tributaries in the Upper River
4.2.1.1. Primary Tributaries
During 2012, select Upper River tributaries were mapped using a combination of low-altitude
aerial video (10 tributaries, Table 4.1-1) and on-the-ground field surveys in a subset of those
videographed tributaries (reaches of Watana Creek, Jay Creek and Kosina Creek). Details of
methods and the results of those field surveys were presented in 2012 Upper Susitna River Fish
Distribution and Habitat Study – Habitat Report (HDR Alaska, Inc. 2013b). Select reaches of
these tributaries, together with additional tributaries that were not conducive to aerial video
mapping (Section 4.2.1.1) were ground surveyed during the 2013 and 2014 field efforts (Figure
4.1-2).
Continuous habitat surveys were conducted within each delineated geomorphic reach (Section
4.1.2.1.2) of each selected tributary. Habitat surveys were conducted over a distance equivalent
to at least 20 consecutive channel widths, with the goal of sampling at least five units of each of
the primary mesohabitat types occurring in the geomorphic reach. Primary mesohabitats were
determined from the video frequency analysis previously described (Table 4.1-3 and Section
4.1.1.2). In tributaries that had not previously been surveyed by videography, primary
mesohabitats were determined by first surveying a complete 20-channel width segment and
assessing the relative dominance of each mesohabitat type within that survey segment. The 20-
channel-width section within each tributary geomorphic reach was selected based on
accessibility and the presence of multiple and varied mesohabitat types. Survey distance was
extended, either contiguously or at another location in the geomorphic reach, to ensure inclusion
of five replicates per primary habitat type. If accessible by foot or helicopter and within the 20
channel width survey length, e.g. not in the bottom of a gorge, non-primary habitats were also
surveyed to the extent possible.
Access by helicopter or cross-country to points along the stream was problematic because many
tributaries were heavily forested. The starting and ending points for field surveys were largely
dependent on accessibility and could not be randomly selected. Many streams were accessed by
helicopter via a landing zone along the Susitna River near the mouth of the tributary. In the
lowest geomorphic reach of each primary tributary, surveyors started the mapping section just
upstream of the ordinary high water line of the mainstem Susitna River. Upstream geomorphic
reaches were surveyed if access and maneuverability within or along the stream was determined
to be safe. Safeness of landing zones was determined by the helicopter pilot. Reasonableness of
conducting the survey was determined by the field crew lead and was dependent on the distance
and difficulty of cross country travel from the helicopter landing zone to the stream section to be
mapped. Conditions preventing access were documented.
During the 2013 and 2014 field seasons, all of the previously selected large and primary
tributaries were ground-surveyed and mapped to the mesohabitat scale (Table 4.1-1).
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4.2.1.2. Smaller and secondary tributaries within the Upper River inundation
zone
Most small tributaries in the Upper River inundation zone are obscured from overhead view due
to a closed canopy of riparian vegetation and thus were not mapped using aerial imagery.
Fifteen of these tributaries were added to those initially selected for ground-surveys in response
to the FERC April 2013 SPD and consultation with the TWG (Table 4.1-3). Survey protocols
for these smaller tributaries are the same as those used in larger tributaries in the Upper River
(Section 4.2.1.1).
4.2.2. Mainstem habitats in the Upper River
Upper River mainstem habitat was remote line-mapped using a hierarchically-nested habitat
typing methodology based on assessment of aerial still imagery, LiDAR, and aerial videography
as described in Section 4.1.1. Reaches UR-1 and UR-2 were classified solely as mainstem (main
channel, off-channel), or tributary habitat. UR-3 through UR-6 were classified to the
mesohabitat level using the available remote imagery (Section 4.1.1.1) with supplemental
information provided from videography (Section 4.1.1.2).
Upper River mainstem field surveys were conducted in accordance with the methods outlined in
Section 4.1.2. The random selection of habitat units for ground-truthing proceeded in two ways.
For single main channel habitat (which lacked obvious survey start and end points) seven units
of each mesohabitat type (or all if less than seven were available) were targeted at random for
ground-truthing of the remote line mapping mesohabitat call and collection of habitat metrics
(Section 4.1.2.2). In all other habitat types, macrohabitat length could be determined prior to the
field effort and so seven units (or all if less than seven available) of these mainstem macrohabitat
types (split main channel, multiple split main channel, side channel, tributary mouth, side slough,
upland slough) were targeted at random for ground-truthing of both macro- and mesohabitat
(Level 3 and Level 4) and collection of habitat metrics. Altogether, field surveys to ground-truth
habitat that had been previously typed by remote imagery were planned for a total of 42 single
main channel mesohabitat units and 42 randomly selected mainstem macrohabitat units within
the Upper River. However, the final selection of habitat units was drawn from habitat units that
both existed and were accessible; thus, the pool of available habitats was less than the targeted
selection and included only 17 available mesohabitats within single main channels and 35
macrohabitat units of other types (Table 4.2-1).
Within single main channel macrohabitat, all targeted and existing mesohabitats were mapped (8
riffles, 9 run/glide units). Pools were not present within single main channel habitats of the
Upper River. While rapids did occur, the consensus of field crew leaders and boat drivers was
that these habitats could not be safely surveyed. Macrohabitat units other than single main
channel were selected to be surveyed to the extent that they were present on the riverscape
(Table 4.2-1). Multiple split main channel habitats were only located within the Upper River in a
single reach at two sites. Among habitats that were both targeted and available, field crews
surveyed 7 split main channel units and 7 side channels, however, two side channels were
reclassified in the field and confirmed as split main channel habitat (see Section 5.1.3) and a
multi-split main channel resulting in a final count of macrohabitat surveys of 8 split main
channel and 5 side channel segments. Field crews surveyed all 6 known upland sloughs in the
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Upper River as well as 7 tributary mouths (Table 4.2-1). A total of 8 side sloughs were surveyed
in the Upper River due to the inclusion of a backwater habitat (formerly considered a
macrohabitat class) that was reclassified as a side slough with backwater mesohabitat following
the April 1, 2013 SPD recommendations.
The special mesohabitat features backwaters, beaver complexes and clearwater plumes, were
scarce in the Upper River, although clearwater plume habitat was present in UR-3 and UR-4
(ISR Part A Appendix B). These mesohabitat units did not occur within single main channel
habitat and, thus, were not targeted during the random selection procedure. Field crews identified
and mapped these special features as they encountered them and although clearwater plumes and
beaver complexes were not encountered, a total of 5 backwater habitats were identified and
mapped during Upper River field surveys.
4.2.2.1 Comparisons between remote and field habitat characterizations in the
Upper River
Determining whether ground-truthing at the range of flows encountered during field surveys was
adequate to meet the study objectives is dependent on the degree and magnitude of difference in
the resulting habitat classifications between remote and field habitat characterizations. This is of
particular concern since target flows were not universally achieved during ground surveys
(Section 4.2.4 and Table 4.2-2).
Remote line mapping was completed in 2012, using aerial imagery collected during 2011. Some
of that imagery was obtained outside the optimal flow range. Particularly during the 2013 field
season, survey teams encountered some unavoidably high flow conditions; every effort was
made to avoid these flows or to survey only the least flow-sensitive habitats, however these flow
variations were considered a factor in the assessment of field calls that differed from the remote
line mapping designation. Additional aerial imagery from 2013 is available that was flown over a
range of flows between approximately 12,000 and 16,000 cfs – this imagery was referred to as
supplementary information to aid in the evaluation of habitat classification differences that co-
occurred with high flows during either the remote line mapping or the field assessment.
Over the 2013 and 2014 field seasons, survey crews classified mesohabitats in a total of 35
macrohabitat segments in the Upper River and for 16 mesohabitat segments of single main
channel habitat (Table 4.2-1). Field habitat classifications for these segments were subsequently
compared with the classifications made during the remote line mapping exercise to identify
possible variations. An initial desktop assessment was made using a simple text-based
comparison in the database between the macrohabitat classification from the 2012 remote line
mapping and the macrohabitat classification made by field survey crews. Differences that
resulted from either typographical variation (differences in naming conventions) or which arose
due to changes to macrohabitat categories were excluded. For example, backwater habitats,
beaver complex and clearwater plume habitat were considered Level 3 macrohabitats in the RSP
but were re-assigned to Level 4 mesohabitat following FERC’s Study Plan Determination. All
remaining discrepancies were flagged for subsequent visual review within the GIS environment.
Senior staff determined whether a difference in categorization arose from the documentation of a
new feature, a difference based on stream channel geometry or change or a difference generated
by different flow levels during observation.
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4.2.3. Lakes within the Upper River Inundation Zone
There are 12 lakes currently known to be within the zone of reservoir inundation, according to
the National Hydrography Database (NHD). These lakes were located, mapped, and identified in
the Project GIS database (Table 4.2-3); elevation, surface area, and perimeter, were calculated
and the presence or absence of surface water connection to the Susitna River was noted. The
lakes identified are shown by number in Figure 4.2-1 and in Table 4.2-3.
The 12 lakes in the proposed reservoir inundation zone were surveyed during July and August,
2014 (Figure 4.2-2). The lakes ranged in elevation between 1,750 and 2,042 ft. msl. The lakes
were numbered from 1 to 12, from the upstream-most location near PRM 214, downstream to
near PRM 195. Only Lake 5 (Sally Lake) was a named lake in the National Hydrography
Database (NHD) database (Table 4.2-3). The 2014 survey intent was to gather basic limnology
information including water depths, water quality (temperature, dissolved oxygen, pH, and
conductivity), and light penetration data at multiple locations throughout the lakes. A two-person
field crew with the aid of an inflatable kayak performed measurements along perpendicular and
longitudinal transects in each lake. Distances from the shoreline starting point for each transect
were calculated from the GPS track line as validated with data from a laser range finder where
horizontal distances were measured at each of the water quality stations described below. The
lakes varied in size ranging between 0.16 ha to 23.0 ha (0.40 – 56.8 acres) and shape (simple to
complex). The number of transects used to provide representative data similarly varied by the
size and shape of each lake.
Depths were collected using hand-held sonar (Hawkeye Model H22PX) at routine distances
along both perpendicular and longitudinal transects to generate sufficient soundings to construct
a bathymetric contour map of the lakes. Hand-held sonar depths were validated frequently using
a metered lead line or in shallow water, a meter stick. Water quality measurements were taken at
select intervals along each perpendicular transects at stations representing 25, 50, and 75 percent
of the horizontal distance across the lake. Water quality measurements were collected with an
YSI Model 556MPS, with the exception of Lakes 1-3 where an YSI ProPlus Model was used.
Calibration for both YSI models followed manufacturer’s specifications. At each station, water
temperature (oC) and dissolved oxygen concentrations (mg/L) were recorded at the surface and at
every 0.5 m depth for lakes with a maximum depth of less than < 5 m and at every 1.0 m depth
for lakes with a maximum depth of greater than or equal to ≥ 5 m. Bottom samples at each
station were collected typically 0.1 m to 0.5 m above the lake bottom to avoid the influence of
bottom sediments on YSI readings. Sampling in this manner allowed the generation of vertical
temperature and DO profiles to document summer stratification conditions. Hydrogen Ion
Activity (pH units) and conductivity (µs/cm) were recorded at the lake surface and bottom at
each water quality station. The depth of light penetration (water transparency) was collected
using a standard 20 cm black and white Secchi disk. The maximum disappearing and subsequent
reappearing depths were recorded at each water quality station along the perpendicular transects.
The Secchi depth was calculated as the average of these two readings. Notes of visual
observations regarding the occurrence of aquatic vegetation (macrophytes and algae) and other
organic matter, the relative tannic color of the water, observations of potential groundwater
influx and fish use were made in each lake where appropriate.
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4.2.4. Variances from the Study Plan
AEA fully implemented the FERC approved study methods with the exception of the following
three variances.
4.2.4.1. Access Limitations
The Study Plan provided that AEA would characterize and map a selection of smaller and
secondary tributaries as discussed in the July 2013 technical memo Characterization and
Mapping of Aquatic Habitats (HDR 2013c). A subset of these tributaries are on Cook Inlet
Regional Working Group (CIRWG) lands that could not be accessed in 2013 (ISR Section
4.2.4.1.2); these tributaries were surveyed in 2014. Uncontrollable access limitations due to high
velocity water, rapids, canyons or other physical barriers, resulted in minimal surveys for two
small Upper River tributaries, both within geomorphic reach UR-3 (tributary ID: H230.8-22H
and H226.2-22H, see Table 4.1-1). Instead, these tributaries were briefly surveyed by helicopter
to estimate dominant habitat types and metrics such as geomorphic reach length and gradient.
4.2.4.2. Ground Survey Flow Conditions
The Study Plan (RSP sections 9.9.5.3.2 and 9.9.5.4.1) provided that ground mapping for Upper
River tributaries would be done at low to moderate flows similar to those which occurred during
aerial videography and mapping of Upper River mainstem habitats would be done at flows near
the range of the reference imagery to allow for similar habitat calls for the two methods. Instead
the study teams mapped habitats in both tributaries and mainstem habitats during all windows of
accessibility in terms of both flow levels and weather conditions (Section 4.1.2.4); flow levels at
the Gold Creek gage during the 2013 and 2014 field mapping seasons are shown in Figure 4.1-1.
This variance from the approved study methods was a consequence of unpredictable flow
throughout the season and could not be avoided even with careful planning. AEA realized that it
would be very difficult to map the large amount of habitat within the short time window where
Susitna River flows were within the targeted range (Figure 4.1-1). Accordingly, AEA prioritized
mapping of habitats more likely to be altered by high flow conditions. Side sloughs were given
highest priority for low flow mapping in order to minimize mapping during potential breaching
flows; the target upper flow for mapping in side sloughs was approximately 18,000 cfs. During
field efforts in 2013 and 2014, 75 percent of Upper River side sloughs were mapped at flows less
than 25,000 cfs –2 side sloughs were mapped at flows greater than 25,000 cfs (Table 4.2-3). A
total of 83 percent of Upper River upland slough habitats were mapped at flows less than 25,000
cfs with just 1 upland slough mapped at flows greater than 25,000 cfs (Table 4.2-3). . This
prioritization strategy was effective and resulted in very few differences in habitat classifications
between ground surveys and remote line mapping despite variable flow conditions (Section
5.1.3).
4.3. Middle River Habitat Mapping
AEA implemented the methods as described in the Study Plan with the exception of the
variances described in ISR Part A Section 4.3.3 and below in Section 4.3.3. As described in
Section 4.1.2.1.1, the Middle River was divided into eight geomorphic reaches. In 2012, remote
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line mapping was applied to the entire Middle River segment as per the methods described in
Section 4.1.1. In 2013 and 2014, field surveys were conducted in selected tributaries (Table 4.1-
4) of the Middle River segment and in randomly selected mainstem habitat units (Table 4.2-1)
following the same selection procedure described for the Upper River (Section 4.2.2).
4.3.1. Tributaries in the Middle River
Matanuska-Susitna Borough LiDAR and aerial imagery were available for the lower extent of
many tributaries within the study area, however, overhanging vegetation, shadows and other
environmental conditions limited characterization of mesohabitats from these sources in 2012.
At higher elevations within tributaries, mesohabitat characterization was not possible from aerial
imagery due to lack of high resolution photography. Subsequently, a subset of seven tributaries
in the Middle River segment within or above Devils Canyon was selected for mesohabitat typing
by videography as described in Section 4.1.1.2 (Table 4.1-4).
A total of six tributaries outside of Focus Areas within and upstream of Devils Canyon in the
Middle River were selected for ground mapping (Tsusena Creek, Unnamed 184.0, Fog Creek,
Devil Creek, Chinook Creek, and Cheechako Creek). These tributaries were also among those
that were videographed in 2012. Two additional tributaries are located in FA-173 (Stephan Lake
Complex) in the Middle River above Devils Canyon. These tributaries were divided into
geomorphic reaches based on tributary basin drainage area and stream gradient according to
criteria described in Section 4.1.2.1.2. Habitat classifications within these tributaries were
ground-truthed according to the same methods described for Upper River tributaries (Section
4.2.1). Devil Creek and one of the tributaries in the Stephan Lake Complex (Unnamed 174.3)
were not fully surveyed due to safety constraints associated with access.
An additional 20 tributaries that were known to contain populations of anadromous and resident
fishes were selected within the zone of hydrologic influence (ZHI) of the proposed Project below
Devils Canyon; 9 occurred within Focus Areas and 11 were outside of Focus Areas. In 2013 and
2014, reaches that were within the zone of hydrologic influence in these tributaries were ground
mapped following field protocols described in Section 4.2.1. However, Lower McKenzie Creek
joins the mainstem Susitna in off-channel habitat, so the surveys of the confluence of Lower
Mckenzie Creek with the main channel are included in mainstem habitat results.
4.3.2. Mainstem Habitats in the Middle River
In 2012, remote line mapping for the Middle River mainstem occurred in an identical fashion as
the Upper River mainstem habitats as described in Section 4.1.1. In addition to the remote
mapping, field surveys were conducted in 2013 and 2014 in accordance with the methods
outlined in Section 4.1.2. The remotely-mapped line segments were used as a starting point to
guide field sampling and unmapped features were added as encountered.
Outside of Focus Areas, Middle River mainstem habitat was ground-mapped by selecting a
random subset of remote line-mapped macro- and mesohabitats using the methods and selection
criteria described in Section 4.2.2. As in the Upper River, the pool of available and accessible
habitats was less than the targeted selection and included 16 mesohabitat segments within single
main channels and 57 units of other macrohabitat types. In addition, private lands limited AEA
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access to some targeted habitat units during 2013 (ISR Section 4.3.3.1); these habitats were
subsequently surveyed during the 2014 field season. Habitat units ground-mapped in the Middle
River mainstem during the 2013 and 2014 field season are presented in Table 4.2-1.
In the April 2013 SPD, FERC directed AEA to identify backwater habitat and give this feature
specific consideration (SPD B-212). The 10 Focus Areas included a diversity of side channels,
side sloughs, and tributary mouths, which often contained a variety of backwater habitats at off-
channel and tributary mouths in the Middle River. A total of 26 backwaters were identified and
mapped within Middle River Focus Areas. An additional 13 backwaters were identified and
mapped during random survey segments outside of Focus Areas in the Middle River. Nine
clearwater plumes and 10 beaver complexes were identified along random survey segments with
a further 28 beaver complexes and 3 clearwater plumes located within Focus Areas; these were
mapped in the same manner as in the Upper River (Sections 4.1.2.3 and 4.2.2).
4.3.2.1. Comparisons between remote and field habitat characterizations in
the Middle River
As for the Upper River, flow variations were considered a factor in the assessment of field
classifications that differed from the remote line mapping designation. Over the 2013 and 2014
field seasons, survey crews classified habitats in a total of 222 macrohabitat segments in the
Middle River and for 39 mesohabitat segments of single main channel habitat (Table 4.2-3).
Inside Focus Areas, survey crews classified habitats in 97 macrohabitat segments with 19
mesohabitat segments of single main channel habitat. (Table 4.2-1). As described for the Upper
River (Section 4.2.4.2), field habitat calls for these segments were subsequently compared with
the classifications made during the remote line mapping.
4.3.3. Variances from the Study Plan
AEA fully implemented the FERC approved study methods with the exception of the following
three variances.
4.3.3.1. Access Limitations
The Study Plan (RSP Sections 9.9.5.3.2 and 9.9.5.4) provided that AEA would characterize and
map a random subsample of mainstem and tributary habitats assuming full access to the Susitna
drainage basin. Additional selection of smaller and secondary tributaries was discussed in the
July 2013 technical memo Characterization and Mapping of Aquatic Habitats (HDR 2013b).
This was not completed in a single year (2013) due to limited private land access. However, after
land access was permitted, additional field surveys occurred in 2014 and all targeted habitats
were surveyed. All mainstem habitat features identified for survey were successfully mapped
during the 2013 and 2014 field mapping efforts. Uncontrollable access limitations due to high
velocity water, rapids, canyons or other physical barriers, resulted in minimal surveys for two
Middle River tributaries (Devil Creek and Unnamed 174.3, see Table 4.1-4). Instead of foot
surveys, these tributaries were surveyed by helicopter to estimate dominant habitat types and
metrics such as geomorphic reach length and gradient.
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4.3.3.2. Ground Survey Flow Conditions
The Study Plan (RSP Section 9.9.5.3.2) provided that ground mapping in the Middle River
would be done at low to moderate flows similar to those which occurred during aerial
videography to allow for similar habitat classification from the two methods. Instead study
teams mapped habitats in both tributaries and mainstem habitats during all windows of
accessibility in terms of both flow levels and weather conditions (Section 4.1.2.4); flow levels at
the Gold Creek gage during the 2013 and 2014 field mapping season are shown in Figure 4.1-1.
This variance from the proposed study methods was a consequence of unpredictable flow
throughout the season that could not have been avoided even with careful planning. AEA
realized that it would be very difficult to map the large amount of habitat, particularly in the
Middle River, within the short time window where Susitna River flows were within the targeted
range (Figure 4.1-1). AEA prioritized mapping of habitats more likely to be altered by high flow
conditions. Side sloughs were prioritized for low flow mapping in order to minimize mapping
during potential breaching flows; the target upper flow for mapping in side sloughs was
approximately 18,000 cfs. During the field effort, 11 side sloughs were mapped at flows meeting
this criteria with a further 14 side sloughs mapped at flows less than approximately 25,000 cfs; 3
side sloughs were mapped at a high flow of 30,700 cfs (Table 4.2-3). Main channel habitats
were prioritized for mapping at flows below 25,000 cfs and were consistently mapped at this
discharge level with 12.9 percent of habitats mapped at flows above this target (Table 4.2-2).
Upland slough habitats were considered lowest priority for low flow mapping and were to be
mapped under flow conditions of 30,000 cfs or less; these were almost entirely mapped to this
criteria with just 3 (of 39) upland sloughs in the Middle River mapped above 30,000 cfs (Table
4.2-2).
4.4. Lower River Habitat Mapping
AEA implemented the methods as described in the Study Plan with no variances. The
Geomorphology study team (Study 6.5, see RSP section 6.5.4.4.2.2 and ISR Part A Section
4.4.2.4) used existing LiDAR and aerial imagery from the Matanuska-Susitna Borough LiDAR
and Imagery Project to map the Lower River. The September 2014 technical memorandum
Mapping of Geomorphic Features and Turnover within the Middle and Lower Susitna River
Segments from 1950s, 1980s, and Current Aerials (Tetra Tech, Inc. 2014) was used to delineate
different geomorphic features in the mainstem Lower Susitna River. As part of that study, aerial
photographs from the 1950s, 1980s and 2012 were reviewed to delineate all geomorphic features
within the Lower River floodplain. For the Lower Susitna River Segment, geomorphic feature
mapping classifications were adapted and modified from the habitat types in Ashton and Trihey
(1985). These included: vegetated areas, exposed substrate, and aquatic macrohabitat types (main
channel, side channels, side sloughs, tributaries, and upland sloughs). Features such as the side
channel complex (SCC), bar island complex (BIC), bar/attached bar (BAB), tributary delta, and
additional open water were added to the set of geomorphic features.
As described in the Study Plan (RSP 9.9.5.4.3), it was impractical to map the entire river
segment beyond Level 3 (macrohabitat) because of the very large size and channel complexity of
the Lower River (Figure 4.4-1). The result of the test videography completed for a short segment
of the Lower River showed that a height of 400 ft or lower with three to five flight paths would
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be necessary to visually differentiate mesohabitat types in the Lower Susitna River segment.
Further, several parallel paths would be extremely difficult to track even with the use of GPS and
would be very difficult to follow during review of the video. In summary, the review of the test
section concluded that aerial videotaping was not a practical method for habitat mapping the
Lower River.
5. RESULTS
This section provides a detailed description of the cumulative results of the Study Plan by major
river segment. Within each river segment the outcomes of both remote line mapping and ground
surveys in both mainstem and tributary habitats are provided. These results are cumulative and
supersede the preliminary results of 2013 surveys presented in the ISR Part A Section 5.
5.1. Upper River
The results of both remote line mapping and ground surveys in mainstem habitat units, tributary
reaches and lakes within the Upper River inundation zone are described in this section using a
combination of habitat distribution and frequencies as well as the presentation of mean values for
habitat metrics within each mesohabitat unit type and are grouped by both macrohabitat
designation and geomorphic reach.
5.1.1. Tributaries in the Upper River
The results presented for tributaries in the Upper River include information previously
summarized in technical memoranda for remote line mapping (HDR 2013a, R2 Resource
Consultants, Inc. 2013b, ISR Appendix B); summaries of habitat distributions and metrics from
ground surveys conducted during 2012 (HDR Alaska, Inc. 2013b); and results from ground
surveys conducted during 2013 and 2014.
5.1.1.1. Tributary Habitat Distribution from Remote Line Mapping (Aerial and
Video)
Tributary geomorphic reach classes were established using aerial video and contour maps. The
primary product of video mapping was a mesohabitat frequency estimate for the selected
tributaries. Preliminary results of the habitat frequency analysis from videography for selected
Upper River tributaries were presented in Appendix 2 of the Fish Distribution and Abundance
Implementation Plan (R2 Resource Consultants, Inc. 2013b). Those results were presented by
study area tributary and included mesohabitat frequency analysis, distribution of mesohabitat
types by river mile and tributary geomorphic reach; and photographs that provide a visual
reference for some of the more prominent habitat types and the general character of each
tributary (R2 Resource Consultants, Inc. 2013b). An updated frequency analysis of mesohabitats
by tributary geomorphic reach is presented in Figure 5.1-1.
5.1.1.2. Tributary Habitat Distribution from Ground Surveys
During 2012, preliminary ground-mapping was conducted in several reaches of Jay, Kosina and
Watana creeks. The relative frequency of each mesohabitat unit type based on length was
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calculated. Details and summary statistics for mesohabitat units within this preliminary effort
were presented in 2012 Upper Susitna River Fish Distribution and Habitat Study: Habitat
Report (HDR Alaska, Inc. 2013b).
During the 2013 and 2014 ground survey efforts, a total of 28 tributaries in the Upper River were
ground mapped including 11 that had been mesohabitat mapped using videography (Section
4.1.1.2, Table 4.1-1). One small tributary in the UR that had been identified for ground mapping
– Unnamed 230.8 – was not surveyed because safe access via either helicopter or jetboat could
not be located. The total length surveyed within these Upper River tributaries was 50, 189 m
(31.2 mi) with an average survey length of 965 m (0.60 mi) within each tributary geomorphic
reach (Table 5.1-1).
Mesohabitats in these tributaries were largely composed of run/glide, riffle, and, boulder riffle
mesohabitats representing 31 percent, 27 percent, and 19 percent of the total length of tributary
habitat surveyed respectively (Table 5.1-1). The mesohabitat composition estimated using the
ground survey protocol was similar to the estimates made from the videographic analysis
(Figures 5.1-1 and 5.1-2). In general, the ground surveys estimated a higher proportion of “fast-
water” habitat types than the video analysis, although the videography documented rare off-
channel habitats that were not captured by the ground survey subsampling (e.g. the beaver pond
in Geomorphic Reach 2 of the Oshetna). This apparent discrepancy is likely related to the size of
the Oshetna River prohibiting full access by wading crews while the wide channel and open
canopy provides excellent coverage of the full channel in the remotes imagery.
Descriptive summary statistics for all habitat metrics by mesohabitat within Upper River
tributaries surveyed during the 2012, 2013, and 2014 field efforts are presented in Tables 5.1-2
through 5.1-18. Average habitat characteristics included mean gradients (outside of alcoves,
which had a mean gradient of 0 percent) ranging from 0.3 percent in pools to 10.4 percent in
cascades. Overall mean bankfull width in all mesohabitats surveyed was 19 m (21 yd) with a
range from 1.4 m (1.5 yd) in alcoves to 22.7 m (24.8 yd) in riffles; overall mean wetted width
was 16.1 m (17.6 yd) and ranged from 1.1 m (1 yd) in alcoves and percolation channels to 19.6
m (21.4 yd) in riffle mesohabitats. Overall mean bankfull depth was 0.8 m (0.9 yd) and ranged
from 0.4 m (1.3 ft) in alcoves to 1.2 m (1.3 yd) in pool and beaver dam mesohabitats; overall
mean thalweg depth was 0.5 m (0.5 ft) and ranged from 0.2 m (0.7 ft) in chute mesohabitats to
0.6 m in run/glides, boulder riffles, beaver ponds and rapids .
Additional habitat characteristics not reported in the ISR include average maximum pool depth
which ranged from 1.3 m (4.3 ft) in beaver ponds to 1.1 m (1.2 yd) in pool mesohabitats; average
pool crest depth of all pool mesohabitats surveyed was 0.4 m (1.3 ft). The overall mean percent
bank erosion was 7.1 percent and ranged from 0 percent in alcoves and falls to 56.3 percent in
chute mesohabitats; overall mean percent undercut bank was 4.7 percent and ranged from 0
percent in alcoves and chutes to 17.1 percent in pool mesohabitats. The total count of large
woody debris (LWD) observed was 1,229 pieces, with 0 pieces observed in chutes and
percolation channels and 359 pieces observed in run/glide mesohabitats. The most common
riparian vegetation surveyed was nonforested shrub willow, observed along 49 percent (24,262
m (15.1 mi)) of the surveyed stream length, while the least common riparian vegetation was
broadleaf forest closed, observed along only 0.66 percent (332 m (0.2 mi)) of stream margins.
Only 1.3 percent (646 m (706 yd) of the habitats surveyed were nonvegetated.
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Substrate types were classified into six categories: bedrock, boulders, cobble, gravel, sand/silt,
and organic material. Boulder was the dominant substrate type observed followed by cobble.
The overall mean bedrock percentage was 0.5 percent and ranged from 0 percent in alcoves,
beaver ponds, and percolation channels to 10 percent in chute mesohabitats; overall mean
boulder cover was 32.9 percent and ranged from 0 percent in beaver ponds to 100 percent in
falls; overall mean cobble cover was 32.2 percent and ranged from 0 percent in beaver ponds to
39.7 percent in riffle mesohabitats; overall mean gravel cover was 22.2 percent and ranged from
3.3 percent in alcoves to 30.1 percent in pool mesohabitats; overall mean sand/silt cover was 9.9
percent and ranged from 2.5 percent in rapids to 76.7 percent in alcove mesohabitats; and overall
mean organics cover was 2.2 percent and ranged from 0 percent in alcoves to 33.3 percent in
beaver pond mesohabitats.
5.1.2. Mainstem Habitats in the Upper River
The results presented below for mainstem habitats in the Upper River include information
previously summarized in technical memoranda for remote line mapping (HDR 2013b, R2
Resource Consultants, Inc. 2013b, ISR Appendix B); summaries of habitat distributions and
metrics from ground surveys conducted during 2012 (HDR Alaska, Inc. 2013b); and results from
ground surveys conducted during 2013 and 2014.
5.1.2.1. Habitat Distribution from Remote Line Mapping (Aerial and Video)
An assessment of the remote line-mapping habitat characterization through videography in the
Upper River indicated that channel type was similar across geomorphic reaches. Approximately
70 percent of the riverine habitat was classified as main channel, 0 to 11 percent as off-channel
habitat, and roughly 25 percent as lower reaches of tributaries (ISR Appendix B). Detailed
methods, analysis and results from the 2012 remote line mapping exercise in the Upper River are
presented in the technical memorandum Upper Susitna River Segment Remote Line Habitat
Mapping (ISR Appendix B).
5.1.2.2. Habitat Distribution from Ground Surveys
The total length of habitat ground surveyed within the Upper River mainstem was 34,429 m
(21.2 mi) composed of 17,168 m of main channel, 5,793 m of (3.6 mi) of split main channel,
2,7739 m (1.7 mi) of multi-split main channel, 1842 m (1.1 mi) of side channel, 3,344 m (2.1 mi)
of side slough, 2,878 m (1.8 mi) of upland slough and 320 m (0.2 mi) of tributary mouth habitat
(Table 4.2-1). The most common Upper River mainstem habitat was single main channel which
represented 50 percent of the total measured habitat by length (Table 5.1-19).
Descriptive statistics for select mesohabitat metrics summarized by macrohabitat within Upper
River mainstem habitat units surveyed are presented in Tables 5.1-19 through 5.1-29. Gradient
was lowest in main channel macrohabitats with a mean gradient of 0.4 percent and was highest
in tributary mouths where the mean gradient was 3 percent. Bankfull width ranged from 10.7 m
(11.7 yd) in upland sloughs to 198.1 m (216.6 yd) in single main channels; wetted widths ranged
from 6.4 m (7.0 yd) in upland sloughs to 169.2 m (185 yd) in single main channel. Average
thalweg depth ranged from 0.3 m (1 ft) in tributary mouths to 2.9 m (9.5 ft) in single main
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channel; bankfull depth averaged 0.9 m (3 ft) in upland and side sloughs to 2.7 m (8.9 ft) in
single main channel macrohabitats.
Mesohabitats in the Upper River mainstem were dominated by run/glide and riffle habitats which
formed 0 percent of the total length of habitat surveyed (Table 5.1-19). Beaver complexes were
not encountered during mainstem surveys in the Upper River. A total of 5 backwaters – 428.9 m
(0.27 mi) of habitat – were surveyed in the Upper River, all were located at the downstream
confluence of side sloughs with mainstem habitats.
5.1.3. Comparisons between remote and field habitat characterizations in the
Upper River
Discrepancies between remote-line mapping and ground-survey habitat calls were infrequent. Of
52 macrohabitat comparisons (including 17 mesohabitat segments within single main channel
habitat) there were two instances where the field-based habitat classifications were judged more
valid than the original line mapping classification. In both cases, the segments were identified as
a side channel during remote line mapping while survey data classified one as a split main
channel and one as a multi-split main channel. A desktop review of this variation concluded that
the field survey assessment was made closer to target flows than occurred with the imagery
underlying the original line mapping macrohabitat classification. Additional variations occurred
either because of changes to the classification system (backwaters, beaver complexes and
clearwater plumes categorized as Level 3 macrohabitats at the time of 2012 remote line mapping
prior to FERC’s SPD change in the hierarchy) or because new segments or features were
identified and mapped during field surveys.
Single main channel habitats were selected separately from other mainstem macrohabitat types to
adjust for indeterminacy of practical survey start and end points in these habitats. Discrepancies
between 2012 remote line mapping mesohabitat classifications and those made by field crews
were almost exclusively an artifact of field crews using finer scale habitat divisions resulting in
the identification of sequences of riffles and runs within segments where remote line mapping
had identified a single mesohabitat or where a glide and a riffle were determined by field crews
to be a riffle and a glide, respectively. AEA judged this kind of habitat difference between
remote line mapping and field calls to be due to the inherent subjectivity of distinctions between
these mesohabitat types in combination with flow variation. Thus, no revisions to line mapping
were needed.
Ground truthing surveys, even at slightly higher flows, resulted in very few habitat classification
changes. Upper River macrohabitat classifications were not sensitive to the range of flows during
survey conditions. The infrequency of classification differences despite greater than planned for
disparities between mapping flows allowed AEA to successfully complete the ground-truthing of
remote-line mapping habitat and fully meet Objectives 1 -3 in the Upper River.
5.1.4. Lakes Within the Upper River Inundation Zone
Elevations of the 12 lakes within the Project inundation zone ranged from 487 m (1,598 ft) to
622 m (2,042 ft), the average perimeter and area were 623 m (2,043 ft) and 2.78 hectares (6.87
acres) respectively. Five lakes had a surface water connection to the Susitna River visible from
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the GIS layer (Table 4.2-2). The maximum depth of lakes ranged from 1.1 to 10.1 m while
average depths ranged between 0.6 m and 4.6 m. Average transparency in these lakes was
determined by the mean secchi depth and ranged between 0.7 and 3.5 m. Surface and bottom pH
was 5.8-7.8 while conductivity varied between surface and bottom on the order of 8.6 μs/cm2 to
247 μs/cm2 – details of these characteristics for each surveyed lake are summarized in Table 4.2-
2. Temperature and dissolved oxygen depth profiles for each lake surveyed are presented in
Figures 5.1-3 and 5.1-4.
5.2. Middle River
The results of both remote line mapping and ground surveys in mainstem habitat units and
tributary reaches within the Middle River are described in this section using a combination of
habitat distribution and frequencies as well as the presentation of mean values for habitat metrics
within each mesohabitat unit type and are grouped by both macrohabitat type and geomorphic
reach.
5.2.1. Tributaries in the Middle River
The results presented for tributaries in the Middle River include information previously
summarized in technical memorandum for remote line mapping (HDR 2013b, R2 Resource
Consultants, Inc. 2013a, b, HDR Alaska, Inc. 2013a) and results from ground surveys conducted
during 2013.
5.2.1.1. Tributary Habitat Distribution from Remote Line Mapping (Aerial and
Video)
Preliminary geomorphic classes and the results of mesohabitat frequency analysis for
videography within Middle River segment tributaries upstream of Devils Canyon are
summarized in Table 4.1-3 and further detailed in Appendix 2 of the Fish Distribution and
Abundance Implementation Plan (R2 Resource Consultants, Inc. 2013b). Results are presented
by study area tributary and include mesohabitat frequency analysis, distribution of mesohabitat
types by river mile and tributary geomorphic reach; and photographs providing a visual reference
of some of the more prominent habitat types and the general character of each tributary.
5.2.1.2. Tributary Habitat Distribution from Ground Surveys
During the 2012, 2013, and 2014 field efforts, habitat surveys were conducted in twenty-five
Middle River tributaries as described in Section 4.3.1. A total of 13,772m (8.6 mi) were
surveyed (Table 5.1-1). Overall mesohabitats in these 25 Middle River tributaries were largely
composed of fast water habitats. The total length of all tributaries combined, by type was 24
percent riffle, 21 percent boulder riffle, and 18 percent run/glide (Table 5.2-1). Descriptive
summary statistics for all habitat metrics by mesohabitat within Middle River tributaries
surveyed during the 2012, 2013, and 2014 field efforts are presented in Tables 5.2-2 through 5.2-
18.
Average habitat characteristics included mean gradients ranging from 0 percent in beaver ponds
to 10 percent in chute mesohabitats; the overall mean gradient in these tributaries was 1.9
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percent. Overall mean bankfull width in all mesohabitats surveyed was 10.8 m (11.8 yd) with a
range from 2.7 m (3 yd) in alcove mesohabitats to 18.5 m (20.3 yd) in beaver pond
mesohabitats. Overall mean wetted width was 8.1 m (8.9 yd) and ranged from 1.6 m (1.7 yd) in
a percolation channel mesohabitat to 13.5 m (14.8 yd) in boulder riffle mesohabitats. The
overall mean bankfull depth was 0.8 m (2.6 ft) and ranged from 0.3 m (1 ft) in run/glides to 1.3
m (1.4 yd) in chute mesohabitats; overall mean thalweg depth was 0.6 m (2 ft) and ranged from
0.2 m (0.7 ft) in alcoves to 1.1 m (1.1 yd) in a chute mesohabitat.
Additional summary of habitat characteristics not found in the ISR includes average maximum
pool depth which ranged from 1.2 m (1.3 yd) in pools to 1.0 m (1.1 yd) in beaver pond
mesohabitats; average pool crest depth of all pool mesohabitats surveyed was 0.3 m (1 ft). The
overall mean percent erosion was 7 percent and ranged from 0 percent in alcoves, beaver ponds,
chutes, and percolation channels to 12.8 percent in pool mesohabitats; overall mean percent
undercut was 5.7 percent and ranged from 0 percent in chutes, and percolation channels to 14.2
percent in pool mesohabitats. The total amount of large woody debris (LWD) observed was
1,229 pieces, with 0 pieces observed in percolation channels and chutes and 359 pieces observed
in run/glide mesohabitats. The most common riparian vegetation surveyed was nonforested
shrub Alder, covering 22 percent (2,985 m [1.9 mi]) of stream, while the least common riparian
vegetation was closed canopy broadleaf forest, covering 3 percent (386 m [0.2 mi]) of the total
stream length surveyed. Only 0.7 percent (99 m [108 yd]) of the total survey length was
nonvegetated.
Substrate types were classified into six types including bed rock, boulders, cobble, gravel,
sand/silt, or organic material. The overall mean bed rock cover was 1 percent and ranged from 0
percent in alcoves, beaver ponds, dry habitats, percolation channels, and riffles to 40 percent in
chute mesohabitats; overall mean boulder cover was 25.4 percent and ranged from 0 percent in
beaver ponds to 57.3 percent in the cascade mesohabitats. Overall mean cobble cover was 24.5
percent and ranged from 0 percent in alcoves and beaver ponds to 38.1 percent in run/glide
mesohabitats; overall mean gravel cover was 28 percent and ranged from 0 percent in alcoves
and beaver pounds to 37.2 percent in riffle mesohabitats. Overall mean sand/silt cover was 12.9
percent and ranged from 0 percent in cascades, chutes, and dry habitats to 100 percent in beaver
pond mesohabitats. Overall mean organics cover was 2.2 percent and ranged from 0 percent in
alcoves to 33 percent in beaver pond mesohabitats.
5.2.2. Mainstem Habitats in the Middle River
The results presented for mainstem habitat in the Middle River include information previously
summarized in technical memoranda for remote line mapping (R2 Resource Consultants, Inc.
2013a, HDR Alaska, Inc. 2013a) and results from ground surveys conducted during 2013and
2014.
5.2.2.1. Habitat Distribution from Remote Line Mapping (Aerial and Video)
Analysis of macrohabitat distribution from the 2012 remote line mapping indicated that
mainstem habitat varied by geomorphic reach and generally increased in complexity from
upstream to downstream locations (HDR Alaska, Inc. 2013a). Single main channel represented
the majority of habitat from the proposed dam site (MR-1) through Devils Canyon (MR-5).
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Downstream of Devils Canyon (i.e., MR-6 to MR-8), channel types were broadly distributed
across channel categories; single main channel habitat was not the majority in any of those
reaches. Downstream reaches contained multiple split main channel habitat and many side
channels.
Mesohabitats in the main channel assessed from the 2012 remote line mapping were generally
dominated by run/glide habitat. Clearwater plume habitats were located in reaches MR-2, MR-3,
MR-5, and MR-7, with the most being in reach MR-2; beaver dams were rarely present in side
slough habitat, and slightly more prevalent in upland sloughs and were only observed in reaches
MR-6 and MR-7. Backwater habitat was also relatively rare and primarily present in the lower
reaches from MR-6 through MR-8. Additional details of methods, analysis and results of
macrohabitat distribution assessed during 2012 remote line mapping are presented in Middle
Susitna River Segment Remote Line Habitat Mapping Technical Memorandum (HDR Alaska,
Inc. 2013a).
5.2.2.2. Habitat Distribution from Ground Surveys
The total length of macrohabitat units surveyed within the Middle River mainstem both inside
and outside Focus Areas (FAs) was 141,474 m (87.9 mi). This was composed of 51,682 m
(32.1 mi) of single main channels, 17,693 m (11 mi) of split main channel, 13,180 m (8.2 mi) of
multiple split main channels, 20,258 m (12.6 mi) of side channels, 18,842 m (11.7 mi) of upland
sloughs, and 1,261 m (0.8 mi) of tributary mouth habitat.
Descriptive statistics for mesohabitat metrics summarized by macrohabitat within all Middle
River mainstem habitat units surveyed are presented in Tables 5.1-19 through 5.1-29. Gradient
was lowest in main channels where the mean gradient was 0.4 percent whereas gradient was
highest in tributary mouth macrohabitats where the mean gradient was 3.0 percent. Bankfull
widths ranged from 10.7 m (11.7 yd) in upland sloughs to 198.1 m (216.6 yd) in single main
channels. Wetted widths ranged from 6.4 m (7 yd) in upland slough macrohabitats to 169.2 m
(184.8 yd) in single main channels. The average thalweg depth ranged from 0.3 m (1 ft) in side
sloughs to 2.9 m (3.2 yd) in single main channels; average bankfull depths ranged from 0.4 m
(1.3 ft) in upland slough macrohabitats to 2.7 m (3 ft) in single main channel macrohabitats.
Habitat metrics collected in Focus Areas were generally similar to those in the Middle River
outside of Focus Areas. Ground-surveyed macrohabitats consisted primarily of main channel
habitats which formed 28 percent and 41 percent by length respectively of the total length of
habitat surveyed within and outside of Focus Areas. Upland sloughs, tributary mouths, and split
main channel macrohabitats were also surveyed in similar proportions. Multi-split main channel
habitats were a higher proportion of surveyed area outside Focus Areas (17 percent versus 9
percent) whereas longer surveys of side channels and side sloughs were completed within Focus
Areas.
5.2.3. Comparisons between remote and field habitat characterizations in the
Middle River
Discrepancies between remote-line mapping or videoed habitat classifications and ground-survey
habitat classifications were infrequent. Of 192 macrohabitat comparisons in the Middle River
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(including 41 mesohabitats within single main channel segments), there were 6 survey lines
where field crew habitat classifications were judged more valid than the original line mapping.
All of these differences were side channels that field crews assessed as side sloughs. A desktop
review of these variations concluded that these represented instances where the field survey
assessment was made closer to target flows than occurred with the imagery underlying the
original line mapping macrohabitat classifications. Thus, 6 variations out of 192 macrohabitat
classifications represent the current misclassification rate associated with the comprehensive
remote line mapping in the Middle River. Additional variations occurred either because of
changes to the classification system (backwaters, beaver complexes and clearwater plumes
categorized as Level 3 macrohabitats at the time of 2012 remote line mapping) or because new
segments or features were identified and mapped during field surveys.
Single main channel habitats were selected separately from other mainstem macrohabitat types to
adjust for indeterminacy of practical survey start and end points in these habitats. Discrepancies
between 2012 remote line mapping mesohabitat classifications and those made by field crews
were almost exclusively an artifact of field crews using finer scale habitat divisions resulting in
the identification of sequences of riffles and runs within segments where remote line mapping
had identified a single mesohabitat. In some instances, a glide and a riffle were determined by
field crews to be a riffle and a glide, respectively. AEA judged this kind of habitat difference
between remote line mapping and field classifications to be due to the inherent subjectivity of
distinctions between these mesohabitat types in combination with flow variation. Thus, no
revisions to line mapping were needed.
Ground truthing surveys, even at slightly higher flows, resulted in very few habitat classification
changes. Middle River macrohabitat classifications were not sensitive to the range of flows
during survey conditions. The infrequency of these differences despite greater than planned for
disparity in mapping flows supports AEA’s contention that the objective of ground-truthing
remote-line mapping habitat classifications has been met.
5.3. Lower River
The September 2014 technical memorandum Mapping of Geomorphic Features and Turnover
within the Middle and Lower Susitna River Segments from 1950s, 1980s, and Current Aerials
(Tetra Tech, Inc. 2014) summarizes geomorphic features in the mainstem Lower Susitna River in
Section 5.1.1 with corresponding maps in Appendix H.
6. DISCUSSION
The objectives of this study were twofold: to establish a baseline against which to evaluate
potential habitat loss or gain caused by Project operations and to provide a habitat template for the
design of coordinated aquatic studies. The specifics of baseline data objectives varied by river
segment to reflect the nature of potential Project effects on aquatic habitats and included
mainstem, tributary and lake habitat data. Remote line mapping results were combined with
2013- 2014 ground-truthing to developed accurate and detailed maps of the baseline habitat
condition with the Upper and Middle River segments. Geomorphic assessments in the Lower
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River (Study 6.5) provided a baseline of macrohabitat mapping that has also supported
coordinated study efforts and will be adequate for any future impact analysis.
The results of the remote line mapping and videography components of the study provide an
index of the frequency and proportion of mainstem and tributary habitats within the Upper and
Middle Susitna River segments. The resolution of the data varied based on the size and visibility
of each habitat unit and relied upon the professional interpretation of biologists. In tributaries,
the comparison of habitat frequencies estimated by 2012 videography and 2013-2014 ground
surveys revealed that the analysis of still images from the videography tended to underestimate
water velocities and thus pool habitats were estimated to be more frequent whereas ground
surveys characterized the same habitats as run/glides. Nonetheless, videography provided a tool
that allowed informed decisions and planning for representing the Susitna basin for instream
flow (Study 8.5) and fish distribution studies (Studies 9.5 and 9.6) during 2013 and a basis for
developing a survey protocol for field confirmation of habitat calls. The interpretation of
videography represented only a small portion of habitat mapping study activity. Significant on-
the-ground activity was conducted in 2013 and 2014 that expanded the resolution and working
knowledge of available habitat in the Susitna River and surrounding tributaries. Future analysis
of habitats in tributaries should use the more comprehensive and accurate ground survey data.
Ground truthing of the remote line mapping effort revealed relatively few inconsistencies
between ground surveys and the remote line mapping. The robust nature of the comprehensive
line mapping product supports its use as a baseline for future analyses. Ground surveys provided
more detailed attributes of macrohabitat types, particularly in off-channel and tributary habitats
where visibility from the air was limited.
6.1. Study Coordination and Updates
Multiple studies used the Aquatic Habitat Study data to inform their efforts including: Instream
Flow (Study 8.5), Fish Distribution and Abundance in the Upper Susitna River (Study 9.5), Fish
Distribution and Abundance in the Middle and Lower Susitna River (Study 9.6), River
Productivity (Study 9.8). This data will also be considered within the Future Watana Reservoir
Fish Community and Risk of Entrainment (Study 9.10).As described in the ISR for Study 8.5,
the 2-D model framework developed for the Instream Flow Study will model all off-channel and
tributary confluences where backwater habitats are generally formed – no further directed
sampling of this habitat type is proposed. The data on backwater habitats generated by the 100
percent coverage of Focus Areas during ground surveys will be used in the Fish and Aquatics
Instream Flow Study (ISR Study 8.5) to specifically include these habitat types in Middle River
Focus Area 2D modeling.
7. CONCLUSION
From 2012 to 2014, AEA completed remote line mapping, videography and ground surveys to
map and characterize aquatic habitats in the Upper and Middle Susitna River. Geomorphological
mapping provides baseline data for the Lower River (Study 6.5). The field work, data collection,
data analysis, and reporting for this Characterization and Mapping of Aquatic Habitats Study
successfully met all study objectives in the FERC-approved Study Plan. The results of this
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Characterization and Mapping of Aquatic Habitats Study are reported herein and earlier by AEA
(2014). With this report, AEA has now completed the Characterization and Mapping of Aquatic
Habitats Study.
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8. LITERATURE CITED
Alaska Department of Fish and Game (ADF&G). 1983. Su Hydro draft basic data report, volume
4, part 1. ADF&G Su Hydro Aquatic Studies Program, Anchorage, Alaska.
Alaska Energy Authority AEA. 2012. Revised Study Plan: Susitna-Watana Hydroelectric Project
FERC Project No. 14241. December 2012. Prepared for the Federal Energy Regulatory
Commission by the Alaska Energy Authority, Anchorage, Alaska. http://www.susitna-
watanahydro.org/study-plan.
AEA. 2014. Initial Study Report: Susitna-Watana Hydroelectric Project FERC Project No.
14241. June 2014.
Ashton, W.W., and E.W. Trihey. 1985. Assessment of Access by Spawning Salmon into
Tributaries of the Lower Susitna River. R&M Associates and E.W. Trihey and
Associates, Final Report to Alaska Power Authority. 66 pp.
Federal Energy Regulatory Commission (FERC). Office of Energy Projects. 2013. April 01,
2013. Study Plan Determination for the Susitna-Watana Hydroelectric Project No 14241-
000.
HDR Alaska, Inc. 2013a. Middle Susitna River Segment Remote Line Habitat Mapping
Memorandum: Susitna-Watana Hydroelectric Project FERC Project No. 14241. January
2013. http://www.susitna-watanahydro.org/wp-content/uploads/2013/02/Att-B-Habitat-
Mapping-Report.pdf
HDR Alaska Inc, 2013b. 2012 Upper River Susitna River Fish Distribution and Habitat Study –
Habitat Report: Susitna-Watana Hydroelectric Project FERC Project No. 14241.
February 2013. http://www.arlis.org/docs/vol1/Susitna2/1/SuWa189.pdf
HDR Alaska, Inc. 2013c. Characterization and Mapping of Aquatic Habitats Technical
Memorandum: Susitna-Watana Hydroelectric Project FERC Project No. 14241. July
2013. http://www.susitna-watanahydro.org/wp-
content/uploads/2013/09/TechMemoCharacterizationMappingOfAquaticHabitats.pdf
Moore, K.M.S., K.K. Jones, and J.M. Dambacher. 2006. Aquatic Inventories Project: Methods
for Stream Habitat Surveys. Oregon Department of Fish and Wildlife, Corvallis, Oregon.
R2 Resource Consultants, Inc. 2013a. Technical Memorandum: Adjustments to Middle River
Focus Areas: Susitna-Watana Hydroelectric Project FERC Project No. 14241. May 2013.
http://www.susitna-watanahydro.org/wp-content/uploads/2013/05/SuWa_R2_TM-
FocusAreasAdjustments.pdf
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
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R2 Resource Consultants, Inc. 2013b. Susitna River Fish Distribution and Abundance
Implementation Plan: Susitna-Watana Hydroelectric Project FERC Project No. 14241.
March 31, 2013 including HDR prepared Appendix 2, Initial Results Aerial Video
Habitat Mapping of Susitna River Tributaries from the Upper Extent of Devils Canyon to
the Oshetna River, January 2013. http://www.susitna-watanahydro.org/wp-
content/uploads/2013/09/SuWa-FSP-2013-Section-09.05-FDAUP.pdf
Tetra Tech. 2014. Mapping of Geomorphic Features and Turnover within the Middle and Lower
Susitna River Segments from 1950s, 1980s, and Current Aerials. Technical
Memorandum. September 26, 2014. Susitna-Watana Hydroelectric Project. Prepared for
the Alaska Energy Authority. Anchorage, Alaska.
Tetra Tech. 2015. Study Implementation Report Attachment 1. Geomorphic Reach Delineation
and Characterization, Upper, Middle, and Lower Susitna River Segments Updated
Technical Memorandum: Susitna-Watana Hydroelectric Project FERC Project No.
14241. October 2015.
Trihey, E.W. 1982. Preliminary assessment of access by spawning salmon to side slough habitat
above Talkeetna. Susitna Hydroelectric Project Doc. No. 134. 24 pp.
U.S. Forest Service (USFS). 2001. Chapter 20 – Fish and Aquatic Stream Habitat Survey. FSH
2090-Aquatic Habitat Management Handbook (R-10 Amendment 2090.21-2001-1).
Wetzel, R.G. 1983. Limnology. 2nd Edition. Published by Harcourt Brace College Publishers.
ISBN 10: 0030579139; ISBN 13: 978003057134,
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9. TABLES
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Table 4.1.1. Nested and tiered habitat mapping units and categories for macrohabitats and mainstem channel mesohabitats.
Level Unit Grouping Category Definitions
1
Major
Hydrologic
Segment
Segments
Upper,
Middle, Lower
River
Upper River – PRM –187.1 – 261.3
(habitat mapping extended up to mainstem PRM 235.1 and included the Oshetna River.
Middle River - PRM –102.4 – 187.1
Lower River - PRM 0 – 102.4
2 Geomorphic
Reach
Upper River
Segment 6 reaches
Middle River
Segment 8 reaches Geomorphic reaches that uniquely divide the Major Hydrologic Segments based on geomorphic characteristics.
Lower River
Segment1 6 reaches
3 Macrohabitat
Main
Channel
Habitat
Single Main
Channel
Single dominant main channel.
Split Main
Channel
Two dominant channels.
Multiple Split
Main Channel
Three or more distributed dominant channels.
Side Channel Channel that is turbid and connected to the active main channel but represents non-dominant proportion of flow1
Tributary
Mouth
Clear water areas that exist where tributaries flow into Susitna River main channel or side channel habitats (upstream
Tributary habitat will be mapped as a separate effort).
Off-Channel
Habitat2
Side Slough Overflow channel contained in the floodplain, but disconnected from the main channel.
Upland
Slough
Similar to a side slough, but contains a vegetated bar at the head that is rarely overtopped by mainstem flow. Has clear
water.1.
Tributary
Habitat
Single
Channel Single dominant channel
Split Channel Two dominant channels
Channel
complex Three or more distributed dominant channels
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Level Unit Grouping Mesohabitat Definitions
4 Mesohabitat
Fast water
Rapid
Swift, turbulent flow including small chutes and some hydraulic jumps swirling around boulders. Exposed substrate
composed of individual boulders, boulder clusters, and partial bars. Lower gradient and less dense concentration of
boulders and white water than Cascade. Moderate gradient; usually 2.0-4.0 percent slope.
Riffle A fast water habitat with turbulent, shallow flow over submerged or partially submerged gravel and cobble substrates.
Generally broad, uniform cross-section. Low gradient; usually 0.5-2.0 percent slope.
Run/Glide
A habitat area with minimal surface turbulence with generally uniform depth that is greater than the maximum
substrate size. Velocities are on border of fast and slow water. Gradients are approximately 0 to less than 2 percent.
Generally deeper than riffles with few major flow obstructions and low habitat complexity.
Slow Water
Pool Slow water habitat with minimal turbulence and deeper due to a strong hydraulic control.
Pool
subtypes
Straight Scour Pool: Formed by mid-channel scour. Generally with a broad scour hole and symmetrical cross-section.
Plunge Pool: Formed by scour below a complete or nearly complete channel obstruction (logs, boulders, or bedrock).
Pool must be Substrate is highly variable. Frequently, but not always, shorter than the active channel width.
Lateral Scour Pool: Formed by flow impinging against one stream bank or partial obstruction (logs, root wad, or
bedrock). Asymmetrical cross-section. Includes corner pools in meandering lowland or valley bottom streams.
Backwater Pool: Found along channel margins; created by eddies around obstructions such as boulders, root wads,
or woody debris. Part of active channel at most flows; scoured at high flow. Substrate typically sand, gravel, and
cobble. Generally not as long as the full channel width.
Isolated Pool: Areas of puddled or stranded water
Special
Habitat
Feature
Clearwater
Plume
Discharge from a tributary that forms a pronounced area of clearwater, in contrast to the turbid water of the main
channel, along the main channel shoreline. The length, breadth, and depth of the clearwater plume depend on the
relative discharge between the tributary and the main channel, relative turbidity, and on mixing conditions along the
shoreline. A clear water plume will be mapped as if it were a separate mesohabitat type.
Backwater Found along channel margins and generally within the influence of the active main channel with no independent
source of inflow. Water is not clear. A backwater will be mapped as if it were a separate mesohabitat type.
Beaver
Complex
Complex ponded water body created by beaver dams. A beaver dam will be mapped as if it were a separate
mesohabitat type.
Tributary
Mesohabitat Tributary mesohabitats were typed using the classification system described in Table 4.1.2
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Table 4.1.2. Nested and tiered habitat mapping units and hydraulic categories used for tributary mesohabitats.
Macrohabitat
(# of channels) Grouping Mesohabitat
Type Definition
Main channel
(1 channel)
Split main channel
(2 channels)
Multiple split main
channel
(3 or > channels)
Fast Water
Falls Steep near vertical drop in water surface elevation greater than approximately 5 feet over a permanent feature, generally
bedrock.
Cascade
A fast water habitat with turbulent flow; many hydraulic jumps, strong chutes, and eddies and between 30-80 percent
white water. High gradient; usually greater than 4 percent slope. Much of the exposed substrate composed of boulders
organized into clusters, partial bars, or step-pool sequences.
Chute
An area where most of the flow is constricted to a channel much narrower than the average channel width. Laterally
concentrated flow is generally created by a channel impingement or a laterally asymmetric bathymetric profile. Flow is
fast and turbulent.
Rapid
Swift, turbulent flow including small chutes and some hydraulic jumps swirling around boulders. Exposed substrate
composed of individual boulders, boulder clusters, and partial bars. Lower gradient and less dense concentration of
boulders and white water than Cascade. Moderate gradient; usually 2.0-4.0 percent slope, occasionally 7.0-8.0 percent.
Boulder Riffle Same flow and gradient as Riffle but with numerous boulders that can create sub-unit sized pools or pocket water created
by scour.
Riffle A fast water habitat with turbulent, shallow flow over submerged or partially submerged gravel and cobble substrates.
Generally broad, uniform cross-section. Low gradient; usually 0.5-2.0 percent slope, rarely up to 6 percent.
Run/Glide
A habitat area with minimal surface turbulence with generally uniform depth that is greater than the maximum substrate
size. Velocities are on border of fast and slow water. Gradients are approximately 0 to less than 2 percent. Generally
deeper than riffles with few major flow obstructions and low habitat complexity.
Slow Water
Pool A slow water habitat with a flat surface slope and low water velocity that is deeper than the average channel depth.
Substrate is highly variable. For pool subtypes, refer to Table 4.1-1.
Beaver Pond Water impounded by the creation of a beaver dam. Equivalent to a Beaver Complex.
Alcove An off-channel habitat that is laterally displaced from the general bounds of the active channel and formed during
extreme flow events or by beaver activity; not scoured during typical high flows. Substrate is typically sand and organic
matter. Generally not as long as the full channel width. An alcove is differentiated from a backwater being more
protected and not scoured at high flows whereas a backwater is part of the active channel and is scoured at high flows.
Off-channel Percolation
channel
A slough characterized by groundwater percolation through the floodplain that comes from main stream channel.
Upstream surface connection to active channel cut off due to accumulation of sediment/debris at the upstream end.
Upstream surface water connection to the active channel present only during high flows.
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Table 4.1-1. Upper River tributary table showing all tributary geomorphic reaches, gradient, basin area, and survey status.
Mainstem
Geomorphic
Reach
Tributary Name Selection
Category
Tributary
Category
2
Tributary
Geomorphic
Reach / Site ID
Project
River
Mile
End of
Survey
Elev.
(ft)
Approx.
Drainage
Area
(km2)
Approx.
Length
(km)
Total
Grad.
(%)
Ground
survey
UR-2 Oshetna River1
Above
Inundation
Zone
1
Oshetna-1
235.1 3000 885.1 89.48
2013
Oshetna-2 2013
Oshetna-33 2013
UR-2 Black River1
Above
Inundation
Zone
2
Black-1
12.6 (LB) 3000 NI NI
2013
Black-2 2013
Black-33 2013
UR-3 Goose Creek1
Above
Inundation
Zone
1
Goose-1
232.8 3000 167.2 40.56
2013
Goose-2 2013
Goose-33 2013
Proposed reservoir full pool (2050’ NAVD88)
UR-3 Unnamed 230.8 small primary* 1 H230.8-22H 230.8 2200 1 2.19 11 2014
UR-3 Unnamed 230.2 small primary 1 H230.2-22H 230.2 2200 0.4 0.72 19 2014
UR-3 Unnamed 230.1 small primary 1 H230.1-22H 230.1 2200 4.3 5.39 7 2014
UR-3 Unnamed 228.5 small primary 1 H228.5-22H 228.5 2200 75.1 25.39 5 2014
UR-3 Unnamed 226.2 small primary 1 H226.2-22H 226.2 2200 5.9 4.50 10 2014
UR-4 Unnamed 219.6 small primary 1 H219.6-22H 219.6 2200 8.4 7.28 8 2014
UR-4 Unnamed 214.4 small primary 1 H214.4-22H 214.4 2200 1.7 2.44 23 2014
UR-4 Jay Creek1 Inundation
Zone 1
Jay-1
211.0 3000 99.5 31.54
2012, 2013
Jay-2 2012, 2013
Jay-3 2012, 2013
Jay-43 2013
UR-4 Kosina Creek1 Inundation
Zone 1
Kosina-1
209.1 3000 644.1 63.57
2012
Kosina-2 2012, 2013
Kosina-3 2012
UR-4 Tsisi Creek1 Inundation
Zone 2 Tsisi-13 7.2 (LB) 3000 NI NI
2013
Tsisi-23 2013
UR-4 Unnamed 208.6 small primary 1 H208.6-22H 208.6 2200 5.0 7.52 8 2014
UR-5 Unnamed 207.4 small primary 1 H207.4-HW1 207.4 HW 1.1 2.50 14 2014
UR-5 Unnamed 207.4
RB-1 small primary 2 H207.4-HW2 207.4 HW NI
2014
UR-5 Unnamed 206.3 Inundation
Zone 1 206.3-1 206.3 3000 49.9 11.96
2013
206.3-3 2013
UR-5 Unnamed 204.5 Inundation
Zone 1 204.5-1 204.5 3000 49.9 9.98
2014
204.5-2 2014
UR-6 Unnamed 198.9 small primary 1 H198.9-22H 198.9 2200 1.2 3.36 13 2014
UR-6 Unnamed 198.4
LB -1 small primary* 2 H198.4-HW 198.4 HW NI
2014
UR-6 Unnamed 197.7 Inundation
Zone 1
197.7-1
197.7 3000 49.9 8.69
2014
197.7-2 2014
197.7-3 2014
UR-6 Unnamed 197.7
RB-1 small primary* 2 H197.7-22T 197.7 2200 NI
2014
UR-6 Watana Creek1 Inundation
Zone 1
Watana-1
196.9 3000 281.3 43.29
2012, 2013
Watana-2 2012, 2013
Watana-33 2013
UR-6 Watana RB-1 small primary* 2 H196.9-HW1 196.9 HW NI
2014
UR-6 Watana LB-1.1.1 small primary* 4 H196.9-HW2 196.9 HW NI
2014
UR-6 Watana
Tributary1
Inundation
Zone 2 Watana Trib-13 8.7 (RB) 3000 NI NI
2013
Watana Trib-23 2013
UR-6 Unnamed 194.8 Inundation
Zone 1
194.8-1
194.8 HW 199.6 11.43
2014
194.8-3 2013
194.8-4 2013
UR-6 Deadman Creek1 Inundation
Zone 1
Deadman-1
189.4 3000 281.8 67.43
2014
Deadman-3 2013, 2014
Deadman-4 2013
Deadman-5 2013
Deadman-6 2013
1Tributary mapped using aerial videography.
2Tributary category indicates ranked distance from the mainstem Susitna River (i.e. 1 = primary tributary to the Susitna River, 2 = tributary to a number 1 tributary)
3Tributary Geomorphic Reach only partially video-mapped or not video mapped. See Table 4.1-3 for spatial range of videography survey.
NI: No information available at this time.
* private land CIRWG
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Table 4.1-2. Middle River tributary geomorphic reaches selected for ground survey, gradient, basin area, and survey year(s).
Mainstem
Geomorphic
Reach
Tributary Name
(ID)
Tributary
Category2
Tributary
Geomorphic
Reach or SiteID
Project
River
Mile
End of Survey
Elev. (ft)
Approx.
Drainage
Area (km2)
Approx.
Length
(km)
Focus Area Ground survey
MR-2 Tsusena Creek1 1
Tsusena-1
184.6 upper extent of
ZHI 145.3 49.41
NA 2014
Tsusena-2 NA Outside of study
bounds (ZHI)
MR-2 Unnamed 184.01 1
184.0-1
184.0 upper extent of
ZHI <31 16.74
NA 2014
184.0-2 NA Outside of study
bounds (ZHI)
MR-2 Fog Creek1 1
Fog-1
179.3 3000 147.2 44.74
NA 2014
Fog-2 NA 2014
Fog-3 NA 2014
Fog-43 NA 2013, 2014
MR-2 Unnamed 174.3 1 H174.3-ZHI 174.3 upper extent of
ZHI NI NI
FA-173
(Stephan Lake
Complex)
ns
MR-2 Unnamed 173.8 1 H173.8-ZHI 173.8 upper extent of
ZHI NI NI
FA-173
(Stephan Lake
Complex)
2013
Devils Canyon upper extent
MR-4 Devil Creek1 1 Devil-1 164.8 upper extent of
ZHI 74.8 25.43 NA 2014
MR-4 Chinook Creek1 1 Chinook-1 160.5 3000 24.7 17.06 NA 2013
Chinook-23 NA 2013
MR-4 Cheechako Creek1 1 Cheechako-1 155.9 barrier 36.4 17.22 NA
2014
Devils Canyon lower extent
MR-5 Portage Creek 1 H152.3-ZHI 152.3 upper extent of
ZHI 178.6 0.31 FA-151
(Portage Cr)
2014
MR-6 Jack Long Creek 1 H148.3-ZHI 148.3 upper extent of
ZHI NI 0.05 NA 2014
MR-6 Unnamed 144.6 1 H144.6-ZHI 144.6 upper extent of
ZHI NI 0.02 FA-144
(Slough 21)
2014
MR-6 Indian River 1 H142.1-ZHI 142.1 upper extent of
ZHI 86.2 0.23 FA-141
(Indian River)
2013
MR-6 Gold Creek 1 H140.1-ZHI 140.1 upper extent of
ZHI 23.7 0.24 NA 2013
MR-6 Fourth of July
Creek 1 H134.3-ZHI 134.3 upper extent of
ZHI NI 0.19 NA 2014
MR-6 Sherman Creek 1 H134.1-ZHI 134.1 upper extent of
ZHI NI 0.03 NA 2014
MR-6 Skull Creek 1 H128.1-ZHI 128.1 upper extent of
ZHI NI 0.06 FA-128
(Slough 8A)
2014
MR-6 Fifth of July Creek 1 H127.3-ZHI 127.3 upper extent of
ZHI NI 0.02 NA 2014
MR-6 Deadhorse Creek 1 H124.4-ZHI 124.4 upper extent of
ZHI 6.5 0.29 NA 2014
MR-7 Little Portage
Creek 1 H121.4-ZHI 121.4 upper extent of
ZHI 2.4 0.19 NA 2012, 2014
MR-7 McKenzie Creek 1 H120.2-ZHI 120.2 upper extent of
ZHI 2.3 0.03 NA 2014
MR-7 Lower McKenzie
Creek 1 H119.7-ZHI 119.7 upper extent of
ZHI NI 0.26 NA 2012, 2014
MR-7 Lane Creek 1 H117.2-ZHI 117.2 upper extent of
ZHI 10.4 0.18 NA 2014
MR-7 Unnamed 115.4 1 H115.4-ZHI 115.4 upper extent of
ZHI NI 0.19 FA-115
(Slough 6A)
2013
MR-7 Gash Creek 1 H115.0-ZHI 115.0 upper extent of
ZHI NI 0.02 FA-113
(Oxbow 1)
2012, 2014
MR-7 Slash Creek 1 H114.9-ZHI 114.9 upper extent of
ZHI NI 0.03 FA-113
(Oxbow 1)
2012, 2014
MR-7 Unnamed 113.7 1 H113.7-ZHI 113.7 upper extent of
ZHI NI NI FA-113
(Oxbow 1)
2014
MR-7 Chase Creek 1 H110.5-ZHI 110.5 upper extent of
ZHI NI 0.27 NA 2013
MR-8 Whiskers Creek 1 H105.1-ZHI 105.1 upper extent of
ZHI 17.2 0.53
FA-104
(Whiskers
Slough)
2013
1 Tributary mapped using aerial videography
2 Tributary category indicates ranked distance from the mainstem Susitna River (i.e. 1 = primary tributary to the Susitna River, 2 = tributary to a number 1 tributary)
3 Tributary geomorphic reach only partially video-mapped or not video-mapped. See Table 4.1-3 for spatial range of videography survey
NI: No information available at this time
* private land: CIRWG** private land: ARRC
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Table 4.1-3. Tributary geomorphic reach mesohabitat frequency and composition derived from videography 2012.
Tributary Geomorphic Reach Alcove Beaver Pond Boulder Riffle Cascade Chute Falls Percolation Pool Rapid Riffle Run/Glide Split Out-of-view All Units
n Percent n Percent n Percent n Percent n Percent n Percent n Percent n Percent n Percent n Percent n Percent n Percent n Percent n
Upper River
Oshetna River Oshetna-1 0 0 0 0 86 42 0 0 1 0 0 0 0 0 4 2 15 7 50 25 46 23 2 1 4 NA 208
Oshetna-2 0 0 16 25 21 33 0 0 0 0 0 0 0 0 0 0 1 2 9 14 1 2 15 24 9 NA 72
Oshetna-31 0 0 0 0 36 18 0 0 0 0 0 0 0 0 7 4 3 2 38 19 67 34 44 23 25 NA 220
Black River Black-1 0 0 0 0 7 12 0 0 0 0 0 0 0 0 1 2 0 0 1 2 20 34 29 50 0 NA 58
Black-2 0 0 0 0 15 42 0 0 0 0 0 0 0 0 3 8 1 3 3 8 8 22 6 17 0 NA 36
Black-3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NA 0
Goose Creek Goose-1 0 0 0 0 43 28 1 1 0 0 0 0 0 0 3 2 37 24 1 1 39 25 32 21 2 NA 158
Goose-2 0 0 0 0 31 34 0 0 0 0 0 0 0 0 2 2 9 10 1 1 33 36 16 17 0 NA 92
Goose-3 Not Surveyed
Proposed reservoir full pool Jay Creek Jay-1 0 0 0 0 11 21 0 0 0 0 0 0 0 0 2 4 5 9 8 15 13 25 14 26 0 NA 53
Jay-2 0 0 0 0 52 34 3 2 4 3 0 0 0 0 6 4 26 17 16 11 32 21 13 9 4 NA 156
Jay-3 0 0 0 0 20 12 0 0 0 0 0 0 0 0 16 9 9 5 13 8 84 49 28 16 5 NA 175
Jay-4 0 0 0 0 4 5 0 0 0 0 0 0 0 0 11 13 2 2 13 16 44 53 9 11 1 NA 84
Kosina Creek Kosina-1 0 0 0 0 18 8 0 0 0 0 0 0 0 0 4 2 104 49 0 0 27 13 59 28 21 NA 233
Kosina-2 0 0 0 0 18 8 0 0 0 0 0 0 0 0 4 2 104 49 0 0 27 13 59 28 21 NA 233
Kosina-3 0 0 0 0 60 28 0 0 0 0 0 0 0 0 3 1 3 1 16 7 61 28 75 34 0 NA 218
Tsisi Creek Tsisi-12 0 0 0 0 50 38 4 3 0 0 0 0 0 0 0 0 56 43 0 0 2 2 18 14 0 NA 130
Tsisi-23 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NA 0
Unnamed 206.3 206.3-1 Not Surveyed
206.3-2 Not Surveyed
206.3-3 Not Surveyed
Unnamed 204.3 204.3-1 Not Surveyed
204.3-2 Not Surveyed
Unnamed 197.7 197.7-1 Not Surveyed
197.7-2 Not Surveyed
197.7-3 Not Surveyed
Watana Creek Watana-1 0 0 0 0 20 5 0 0 0 0 0 0 0 0 14 4 30 8 30 8 208 55 75 20 7 NA 384
Watana-2 0 0 0 0 11 6 1 1 2 1 0 0 0 0 7 4 66 35 6 3 57 30 37 20 3 NA 190
Watana-34 0 0 0 0 9 13 0 0 0 0 0 0 0 0 0 0 3 4 5 7 10 14 43 61 2 NA 72
Watana Trib Watana Trib-15 0 0 0 0 10 10 0 0 0 0 0 0 0 0 1 1 3 3 1 1 78 74 12 11 0 NA 105
Unnamed 194.8 194.8-1 Not Surveyed
194.8-2 Not Surveyed
194.8-3 Not Surveyed
194.8-4 Not Surveyed
Deadman Creek Deadman-1 0 0 0 0 1 13 0 0 0 0 0 0 0 0 1 13 6 75 0 0 0 0 0 0 0 NA 8
Deadman-2 0 0 0 0 0 0 14 50 6 21 2 7 0 0 3 11 3 11 0 0 0 0 0 0 1 NA 29
Deadman-3 0 0 0 0 21 30 2 3 0 0 0 0 0 0 5 7 32 46 0 0 0 0 10 14 0 NA 70
Deadman-4 0 0 0 0 28 22 0 0 0 0 0 0 0 0 6 5 21 16 12 9 34 26 29 22 1 NA 131
Deadman-5 0 0 0 0 19 31 0 0 0 0 0 0 0 0 2 3 25 40 0 0 13 21 3 5 1 NA 63
Upper River Total 0 0 16 0 591 19 25 2 13 1 2 0 0 0 105 4 564 18 223 6 904 23 628 18 107 NA 3,178
Middle River
Tsusena Creek Tsusena-1 0 0 0 0 2 3 1 1 0 0 0 0 0 0 1 1 37 50 0 0 18 24 15 20 0 NA 74
Tsusena-2 0 0 0 0 0 0 8 16 4 8 0 0 0 0 6 12 18 35 0 0 12 24 3 6 1 NA 52
Unnamed 184.0 184.0-1 0 0 0 0 2 6 5 14 0 0 0 0 0 0 1 3 21 60 0 0 5 14 1 3 0 NA 35
184.0-2 0 0 0 0 0 0 12 26 2 4 1 2 0 0 0 0 24 52 0 0 7 15 0 0 3 NA 49
Fog Creek Fog-1 0 0 0 0 3 8 0 0 0 0 0 0 0 0 2 5 3 8 2 5 2 5 27 69 0 NA 39
Fog-2 0 0 0 0 25 21 11 9 5 4 0 0 0 0 15 13 51 43 7 6 1 1 5 4 1 NA 121
Fog-3 0 0 0 0 83 15 0 0 0 0 0 0 0 0 53 10 18 3 164 30 125 23 106 19 34 NA 583
Fog-46 0 0 0 0 5 26 0 0 0 0 0 0 0 0 1 5 7 37 2 11 0 0 4 21 2 NA 21
Fog Trib Fog Trib-17 0 0 0 0 2 1 46 18 6 2 0 0 0 0 5 2 105 41 1 0 41 16 51 20 5 NA 262
Upper extent of Devils Canyon
Chinook Creek Chinook-1 0 0 0 0 2 2 20 17 14 12 0 0 0 0 5 4 63 54 0 0 12 10 0 0 21 NA 137
Chinook-28 0 0 0 0 1 2 0 0 0 0 0 0 0 0 0 0 22 42 2 4 11 21 16 31 7 NA 59
Cheechako Creek Cheechako-1 0 0 0 0 4 5 19 26 9 12 3 4 0 0 11 15 21 28 0 0 7 9 0 0 8 NA 82
Lower extent of Devils Canyon
Middle River Total 0 0 0 0 134 7 136 11 50 4 4 0 0 0 100 5 431 39 178 4 247 13 233 15 82 NA 1,595
1Video went to TRM 15.6 but reach extends to TRM 25.6
2Video stops at RM 2.7 so habitat frequencies in table above only go from RM 0.1 to RM 2.7 (not full reach length of 3.5). 3No video, channel form is assumed based on topography and location within the watershed. 4Video stops at RM 17.25, habitat frequencies in table above only go from RM 14.41 to RM 17.25 (not full reach length of 21.5). The helicopter video only extends to RM 17.25 but it is assumed the rest of the reach continues in the same character. 5Video stops at RM 2.95, habitat frequencies in table above only go from RM 0.1 to RM 2.95 (not full reach length of 10.7). After the helicopter video ends, it is assumed the channel continues in the same character to RM 4.6, where it splits. The main channel is assumed to go to the right through the broad valley up to the
drainage break into Butte Creek.
6Helicopter did not extend to 3,000 ft elevation but same character is inferred and stream just gets smaller. This reach was only mapped to RM 17.975 so habitat above this point is not included. 7Video mapping only goes to RM 7.38, habitat units after RM 7.38 not included. 8Video mapping only goes to RM 7.1 habitat units above RM 7.1 are not included.
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Table 4.2-1. Number of randomly selected Upper and Middle River mainstem macrohabitats survyed and total number of Focus Area mainstem macrohabtiats surveyed during 100 percent ground survey coverage.
Main Channel1 Multi-Split Main
Channel
Split Main
Channel Side Channel Side Slough Upland Slough Tributary
Mouth
Special Habitat Features
Geomorphic Reach
Run/
Glide Riffle Pool Backwater Beaver
Complex2
Clearwater
Plume
Upper River
UR-3 4 5
1
3
UR-4 2 3
5 2 5 5 1 4
UR-5
1 1
2
UR-6 2 1 2 2 2 1 1 1
Upper River Total 8 8 1 8 5 8 6 7 5
Middle River
MR-2 1 1 1 1 2 1 2
MR-3 1 1
1 2
2 1
MR-4*
MR-5
1
MR-6 3 1 4 4 3 7 7 2 6 6 4
MR-7 5 1
2 1 3 3 1 2 4 2
MR-8 2 6 1 1
1 4
Middle River Total 12 4 10 9 7 11 12 7 13 10 9
Focus Area Surveys
MR-1 1 2
MR-2 1
3 6 3 1 1 4
MR-5 1
1 1 1
MR-6 6 3 1 12
21 6 16 2 16 16
MR-7 1
16 1 4 8 2 4 7
MR-8 1
12 7 3 4 2 2
Focus Area Total 11 3 1 12 16 39 23 30 6 26 28 3
Notes:
1 Main Channel macrohabitats were selected and surveyed by available mesohabitats, see section 4.2-2 for discussion.
2 As requested by FERC (SPD 2013) Beaver Complex is a mesohabitat designation that represents a single pool or pond formed by beaver activity – thus this count may represent multiple ponds within a single Macrohabitat feature
* All habitat units in Middle River geomorphic reach 4 are within or near Devils Canyon, were deemed unsafe and were not ground surveyed
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Table 4.2-2. Lakes in the Upper River located within the inundation zone, and habitat metrics obtained from the Project GIS database or measured in the field.
Lake ID
Surface
water
connection
% of
max
depth
pH Conductivity (μs/cm2 )
Perimeter
(m)
Elevation
(ft)
Area
(ha)
Littoral
area %
Avg.
depth (m)
Max depth
(m)
Secchi
depth (m) Surface Bottom Surface Bottom
Lake 1 260 1752 0.23 Yes 55.6 0.9 1.8 1.0 54.2 7.0 na 247.0 na
Lake 2 543 1750 0.68 Yes 55.9 1.0 2.0 1.0 50.0 7.0 na 116.0 na
Lake 3 1001 1796 3.37 Yes 53.1 4.1 8.3 3.4 41.1 7.6 na 311.0 na
Lake 4 441 2042 1.15 No 62.5 2.6 4.2 2.0 47.1 6.0 5.8 8.6 9.3
Lake 5 3009 2034 22.99 Yes 46.4 3.0 8.0 2.7 34.3 7.8 7.5 110.4 108.8
Lake 6 399 2008 0.89 No 53.6 4.6 10.1 3.5 34.9 7.6 7.5 98.9 110.4
Lake 7 467 1598 1.48 Indeterminate 57.7 3.1 6.4 1.5 22.7 7.0 6.6 51.9 68.4
Lake 8 211 2030 0.3 No 43.8 2.0 3.1 1.6 52.8 6.8 6.3 49.8 55.7
Lake 9 419 1782 1.15 Yes 59.1 0.6 1.4 0.7 49.2 6.9 6.8 93.1 106.4
Lake 10 144 1958 0.16 No 57.1 0.8 1.4 1.1 79.6 6.7 6.7 53.2 52.8
Lake 11 198 2038 0.2 No 62.5 0.6 1.1 0.9 78.8 6.2 6.2 29.8 29.7
Lake 12 391 2008 0.72 No 62.5 1.0 2.5 1.5 60.8 6.6 6.7 43.9 42.1
Note: Lakes are ordered from most upstream to most downstream.
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Table 4.2-3. Range of mean daily flows at the USGS 15292000 Susitna River at Gold Creek real time streamflow gage
during ground surveys.
River
Segment Macrohabitat Type
Susitna River at Gold Creek Discharge Grand
Total < 18,000
cfs
18,000 to
25,000 cfs
25,000 to
30,000 cfs
> 30,000
cfs
Upper River
Single Main Channel 1 2 11 14
Multi-Split Main Channel 2 2
Side Channel 3 1 2 6
Split Main Channel 1 3 4 8
Tributary Mouth 5 2 7
Side Slough 4 2 2 8
Upland Slough 2 3 1 6
Upper River Subtotal 16 16 20 51
Middle River
Single Main Channel 10 20 7 2 39
Multi-Split Main Channel 1 21 22
Side Channel 19 24 1 2 46
Split Main Channel 20 3 2 25
Tributary Mouth 2 7 4 13
Side Slough 16 14 2 2 34
Upland Slough 11 24 8 43
Middle River Subtotal 79 6 113 24 222
Grand Total 79 26 129 39 273
Notes:
1No date or flow information available from field data.
*Side Sloughs in the Upper River were evaluated prior to surveys to ensure that the head of the unit was not breached during flows > 18,000
cfs as measured at the Susitna River at Gold Creek gage.
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Table 5.1-1. Sum of length (m) surveyed, and composition by length of mesohabitats in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) & Percent n Length
Oshetna River Oshetna-3 5 616 16% 2 590 15% 8 921 23% 15 1,809 46% 30 3,936
Oshetna-2 3 792 73% 2 171 16% 1 115 11% 6 1,078
Oshetna-1 5 483 12% 2 228 6% 5 1,744 45% 5 1,413 37% 17 3,868
Black River Black-3 5 207 15% 2 69 5% 5 586 43% 5 506 37% 17 1,368
Black-2 7 593 54% 1 60 5% 3 187 17% 6 263 24% 17 1,103
Black-1 4 494 24% 1 34 2% 5 1,105 53% 5 456 22% 15 2,089
Goose Creek Goose-3 5 247 41% 1 118 19% 6 243 40% 12 609
Goose-2 5 675 58% 3 317 27% 5 167 14% 13 1,158
Goose-1 7 1,056 75% 1 58 4% 5 164 12% 5 129 9% 18 1,407
Proposed reservoir full pool
Unnamed 230.2 NA 1 54 100% 1 54
Unnamed 230.1 NA 3 115 75% 3 17 11% 1 22 14% 7 154
Unnamed 228.5 NA 3 143 30% 5 252 52% 1 27 6% 3 63 13% 12 485
Unnamed 226.2 NA 1 50 100% 1 50
Unnamed 219.6 NA 4 193 100% 4 193
Unnamed 214.4 NA 1 224 100% 1 224
Jay Creek Jay-4 1 7 1% 5 102 20% 5 187 37% 6 208 41% 17 503
Jay-3 5 300 28% 3 39 4% 2 35 3% 7 691 65% 17 1,065
Jay-2 5 302 17% 6 640 37% 4 183 11% 5 607 35% 20 1,732
Jay-1 3 325 30% 1 9 1% 1 10 1% 2 22 2% 1 37 3% 11 343 32% 15 331 31% 34 1,077
Tsisi Creek Tsisi-2 5 381 62% 5 236 38% 10 617
Tsisi-1 8 469 46% 6 407 40% 1 140 14% 15 1,016
Kosina Creek Kosina-3 2 - - 2 - - 4 395 17% 26 1,909 83% 34 2,304
Kosina-2 1 81 2% 2 134 3% 1 26 1% 5 428 10% 17 2,452 60% 16 970 24% 42 4,091
Kosina-1 2 37 3% 14 858 59% 13 566 39% 29 1,461
Unnamed 208.6 NA 1 61 100% 1 61
Unnamed 207.4 RB-1 207.4 RB-1 1 80 100% 1 80
Unnamed 207.4 NA 6 128 100% 6 128
Unnamed 206.3 206.3-3 1 3 16% 2 10 50% 1 7 34% 4 20
206.3-1 4 69 28% 6 119 48% 1 40 16% 1 18 7% 12 246
Unnamed 204.5 204.5-2 1 146 100% 1 146
204.5-1 3 93 22% 7 315 74% 1 7 2% 1 9 2% 12 423
Unnamed 198.9 NA 1 63 100% 1 63
Unnamed 198.4 LB-1 NA 1 46 100% 1 46
Unnamed 197.7 197.7-3 2 27 35% 2 49 65% 4 76
197.7-2 3 120 90% 1 14 10% 4 134
197.7-1 2 54 12% 3 75 17% 2 19 4% 3 236 53% 1 43 10% 1 17 4% 12 443
Unnamed 197.7 RB-1 NA 3 286 93% 1 21 7% 4 307
Watana Creek Trib Watana Trib-2 3 26 18% 2 44 31% 5 72 51% 10 142
Watana Trib-1 1 18 3% 1 22 4% 2 65 12% 2 151 27% 8 293 53% 14 549
Watana Cr. LB-1.1.1 NA 1 141 41% 2 96 28% 2 108 31% 5 345
Watana Creek RB-1 NA 3 38 20% 1 31 16% 1 23 12% 4 46 24% 4 50 26% 13 188
Watana Creek Watana-3 2 29 3% 13 470 48% 3 59 6% 4 143 15% 7 269 28% 29 969
Watana-2 2 81 7% 2 128 11% 1 22 2% 2 35 3% 6 586 48% 5 368 30% 18 1,219
Watana-1 1 47 2% 1 98 4% 2 46 2% 6 201 7% 17 1,659 60% 12 731 26% 39 2,782
Unnamed 194.8 194.8-4 6 71 44% 4 89 56% 10 159
194.8-3 2 148 22% 2 20 3% 2 22 3% 9 255 38% 3 39 6% 1 5 1% 6 178 27% 25 667
194.8-1 2 365 96% 1 17 4% 3 382
Deadman Creek Deadman-6 6 868 43% 5 1,155 57% 11 2,022
Deadman-5 5 623 52% 5 567 48% 10 1,190
Deadman-4 5 1,282 44% 5 469 16% 5 1,139 39% 15 2,890
Deadman-3 6 428 18% 5 1,090 46% 1 39 2% 6 755 32% 2 58 2% 20 2,368
Deadman-1 1 124 25% 1 28 6% 1 352 70% 3 504
Total1 3 36 0.07% 3 195 0.39% 112 9,375 19% 60 3,667 7% 2 85 0.17% 2 111 0.22% 10 336 1% 48 1,074 2% 72 6,329 13% 144 13,551 27% 221 15,431 31% 677 50,189
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 44 October 2015
Table 5.1-2. Mean (±SD) percent gradient of mesohabitats in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 0.4 0.1 1 2.0 - 8 0.6 0.6 15 0.6 0.5 29 0.6 0.5
Oshetna-2 3 1.5 0.5 2 1.5 0.7 1 1.0 - 6 1.4 0.5
Oshetna-1 5 1.0 0.0 2 2.5 0.7 5 1.0 0.6 5 0.9 0.7 17 1.2 0.7
Black River Black-3 5 1.8 0.8 2 2.3 0.4 5 1.1 0.4 5 0.6 0.4 17 1.3 0.8
Black-2 7 2.5 0.6 1 3.0 - 3 1.2 0.8 6 0.4 0.3 17 1.6 1.1
Black-1 4 2.5 1.2 1 0.0 - 5 0.9 0.4 5 0.7 0.3 15 1.2 1.0
Goose Creek Goose-3 5 0.9 0.2 1 1.0 - 6 0.4 0.2 12 0.6 0.3
Goose-2 5 1.8 0.6 2 17.0 18.4 5 0.4 0.4 12 3.7 8.4
Goose-1 7 2.9 1.2 1 4.0 - 5 4.0 1.7 5 1.0 1.1 18 2.7 1.7
Proposed reservoir full pool
Unnamed 230.2 NA 1 27.0 - 1 27.0 -
Unnamed 230.1 NA 2 24.3 7.4 1 0.0 - 1 6.0 - 4 13.6 13.2
Unnamed 228.5 NA 3 6.2 1.8 5 5.4 0.9 1 4.0 - 3 1.3 0.8 12 4.5 2.2
Unnamed 226.2 NA
Unnamed 219.6 NA 1 5.5 - 1 5.5 -
Unnamed 214.4 NA 1 15.0 - 1 15.0 -
Jay Creek Jay-4 5 0.5 0.0 5 1.5 0.5 6 0.8 0.3 16 0.9 0.5
Jay-3 5 2.2 0.6 2 - - 2 1.5 0.7 7 1.2 0.6 16 1.6 0.7
Jay-2 5 1.7 0.6 6 3.3 1.4 4 1.4 0.5 5 1.7 0.4 20 2.1 1.2
Jay-1 3 3.5 0.5 1 - - 1 - - 1 5.0 - 9 1.0 0.0 11 1.7 1.2 26 2.5 1.5
Tsisi Creek Tsisi-2 5 1.0 0.6 5 0.4 0.2 10 0.7 0.5
Tsisi-1 8 2.0 0.5 6 2.3 0.9 1 0.5 - 15 2.0 0.8
Kosina Creek Kosina-3 3 1.3 0.6 14 1.0 0.0 17 1.1 0.3
Kosina-2 1 5.0 - 2 1.0 - 1 1.0 - 5 3.3 1.0 15 1.0 0.0 15 1.0 0.0 39 1.4 1.1
Kosina-1 2 1.0 0.0 14 1.0 0.0 13 1.0 0.0 29 1.0 0.0
Unnamed 208.6 NA 1 27.5 - 1 27.5 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 3 19.6 1.3 3 19.6 1.3
Unnamed 206.3 206.3-3
206.3-1 2 6.8 0.4 6 11.2 1.8 1 6.0 - 9 9.6 2.7
Unnamed 204.5 204.5-2 1 10.0 - 1 10.0 -
204.5-1 6 8.4 2.2 6 8.4 2.2
Unnamed 198.9 NA 1 12.0 - 1 12.0 -
Unnamed 198.4 LB-1 NA 1 12.0 - 1 12.0 -
Unnamed 197.7 197.7-3 2 3.5 0.7 2 1.5 0.7 4 2.5 1.3
197.7-2 3 4.1 0.9 1 4.0 - 4 4.1 0.7
197.7-1 2 3.5 0.7 3 5.7 0.6 1 0.0 - 3 4.0 0.0 1 3.0 - 1 0.0 - 11 3.5 2.0
Unnamed 197.7 RB-1 NA 3 4.7 2.1 1 3.0 - 4 4.3 1.9
Watana Creek Trib Watana Trib-2 1 2.5 - 2 3.0 0.0 2 1.3 0.4 5 2.2 0.9
Watana Trib-1 1 0.0 - 1 0.0 - 2 2.3 0.4 2 1.8 0.4 8 0.9 0.5 14 1.1 0.8
Watana Cr. LB-1.1.1 NA 1 0.5 - 2 2.0 0.0 1 2.0 - 4 1.6 0.8
Watana Cr. RB-1 NA 2 19.0 8.5 1 50.0 - 1 1.0 - 1 2.5 - 1 1.0 - 6 15.4 19.4
Watana Creek Watana-3 1 0 - 12 1.9 0.3 3 2.8 0.3 4 1.5 0.7 6 1.3 0.8 26 1.7 0.8
Watana-2 2 2.0 0.0 2 1.0 0.0 1 0.0 - 2 3.5 2.1 6 1.1 0.2 5 0.9 0.3 18 1.4 1.1
Watana-1 1 1 - 1 1.5 - 2 1.0 0.0 5 0.7 0.4 17 1.1 0.3 12 1.0 0.0 38 1.0 0.3
Unnamed 194.8 194.8-4 4 0.0 0.0 3 1.8 0.8 7 0.8 1.1
194.8-3 2 0 0 2 5.0 0.0 1 4.0 - 9 0.0 0.0 2 4.0 0.0 6 1.8 0.3 22 1.5 1.8
194.8-1 2 3.3 1.1 1 1.0 - 3 2.5 1.5
Deadman Creek Deadman-6 6 0.3 0.2 4 0.1 0.1 10 0.2 0.2
Deadman-5 5 1.8 0.4 5 1.9 1.0 10 1.9 0.7
Deadman-4 5 1.0 0.4 5 2.0 0.4 5 0.3 0.2 15 1.1 0.8
Deadman-3 6 1.9 1.0 3 4.4 0.9 1 4.0 - 6 2.6 0.5 2 0.3 0.4 18 2.5 1.4
Deadman-1 1 3.5 - 1 0.5 - 1 2.4 - 3 2.1 1.5
Total1 1 0 - 3 0.33 0.58 104 2.1 1.2 47 10.4 7.7 2 8.0 5.7 1 50.0 - 8 0.8 0.4 38 0.3 0.4 70 3.1 1.3 129 1.2 0.9 191 0.9 0.6 594 2.3 4.0
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 45 October 2015
Table 5.1-3. Mean (±SD) bankfull width (m) of mesohabitats in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 33.7 9.6 2 60.2 0.3 8 27.7 10.4 15 36.0 20.8 30 35.0 17.5
Oshetna-2 3 51.4 2.8 2 66.4 7.6 1 56.9 - 6 57.3 8.3
Oshetna-1 5 37.8 4.5 2 54.1 6.8 5 55.9 4.6 5 49.0 6.1 17 48.3 8.9
Black River Black-3 5 28.0 1.3 2 20.9 2.2 5 26.4 5.1 5 26.6 3.3 17 26.3 3.8
Black-2 7 22.4 6.8 1 23.1 - 3 15.4 9.2 6 18.8 5.4 17 19.9 6.7
Black-1 4 21.6 7.0 1 25.6 - 5 36.7 35.1 5 23.7 7.8 15 27.6 20.6
Goose Creek Goose-3 5 13.8 3.7 1 16.7 - 6 13.4 5.0 12 13.9 4.1
Goose-2 5 22.2 4.1 3 23.1 8.5 5 16.4 1.5 13 20.2 5.3
Goose-1 7 18.0 2.9 1 18.6 - 5 14.3 3.5 5 14.9 3.0 18 16.1 3.3
Proposed reservoir full pool
Unnamed 230.2 NA 1 1.3 - 1 1.3 -
Unnamed 230.1 NA 3 4.6 0.8 3 4.2 1.2 1 3.7 - 7 4.3 0.9
Unnamed 228.5 NA 3 11.5 0.3 5 11.2 1.0 1 11.6 - 3 8.0 1.8 12 10.5 1.8
Unnamed 226.2 NA
Unnamed 219.6 NA 4 6.2 1.9 4 6.2 1.9
Unnamed 214.4 NA 1 9.4 - 1 9.4 -
Jay Creek Jay-4 1 0.9 - 5 6.3 0.8 5 8.1 1.5 6 6.1 1.9 17 6.4 2.2
Jay-3 5 12.1 2.9 3 6.0 6.1 2 6.5 6.4 7 8.8 5.6 17 9.0 5.1
Jay-2 5 14.3 6.3 6 12.1 3.6 4 13.0 0.9 5 12.7 2.8 20 13.0 3.8
Jay-1 3 9.7 4.8 1 11.0 - 1 5.0 - 2 8.5 0.7 1 9.0 - 11 10.3 3.1 15 11.1 3.4 34 10.3 3.3
Tsisi Creek Tsisi-2 5 16.9 3.2 5 16.1 2.4 10 16.5 2.7
Tsisi-1 8 14.7 6.2 6 15.4 4.3 1 5.2 - 15 14.3 5.7
Kosina Creek Kosina-3 3 62.0 53.1 14 69.0 40.0 17 67.8 40.7
Kosina-2 1 56.0 - 2 3.3 1.1 1 16.0 - 5 34.7 9.3 17 34.2 16.5 16 25.4 15.7 42 29.5 16.7
Kosina-1 2 16.0 1.4 14 24.0 13.5 13 20.5 9.8 29 21.9 11.4
Unnamed 208.6 NA 1 2.7 - 1 2.7 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 1.9 1.2 6 1.9 1.2
Unnamed 206.3 206.3-3 1 2.3 - 2 7.1 1.1 1 2.9 - 4 4.8 2.7
206.3-1 4 5.1 0.3 6 4.5 1.1 1 4.0 - 1 4.7 - 12 4.6 0.9
Unnamed 204.5 204.5-2 1 6.6 - 1 6.6 -
204.5-1 3 5.1 1.2 7 5.5 2.3 1 1.6 - 1 3.2 - 12 4.9 2.2
Unnamed 198.9 NA 1 2.0 - 1 2.0 -
Unnamed 198.4 LB-1 NA 1 2.1 - 1 2.1 -
Unnamed 197.7 197.7-3 2 3.4 0.9 2 3.1 0.1 4 3.2 0.5
197.7-2 3 4.5 0.8 1 4.2 - 4 4.4 0.7
197.7-1 2 8.8 0.6 3 8.4 1.7 2 4.9 4.0 3 9.6 4.4 1 8.9 - 1 4.9 - 12 7.9 3.0
Unnamed 197.7 RB-1 NA 3 4.9 1.7 1 6.7 - 4 5.3 1.6
Watana Creek Trib Watana Trib-2 3 2.2 0.5 2 2.4 0.2 5 2.4 0.5 10 2.3 0.4
Watana Trib-1 1 2.8 - 1 15.4 - 2 18.0 1.9 2 16.5 3.9 8 12.4 2.0 14 13.3 4.2
Watana Creek LB-1.1.1 NA 1 5.2 - 2 1.3 0.2 2 1.6 1.0 5 2.2 1.7
Watana Creek RB-1 NA 3 1.8 1.0 1 5.9 - 4 1.8 0.3 4 2.3 1.0 12 2.3 1.4
Watana Creek Watana-3 2 1.7 0.2 13 12.8 5.6 3 9.9 0.9 4 13.7 6.0 7 10.2 3.8 29 11.2 5.4
Watana-2 2 14.6 0.7 2 2.8 0.4 1 10.5 - 2 14.9 4.3 6 10.2 4.1 5 14.9 1.8 18 11.7 4.7
Watana-1 1 16.0 - 1 19.3 - 2 1.6 0.3 6 16.0 16.2 17 21.4 11.9 12 17.4 7.1 39 18.1 11.3
Unnamed 194.8 194.8-4 6 4.3 1.1 4 4.4 1.1 10 4.3 1.1
194.8-3 2 7.5 0.7 2 4.8 1.6 2 6.8 0.7 9 6.1 1.0 3 4.6 0.7 1 7.5 - 6 5.7 1.2 25 6.0 1.2
194.8-1 2 8.7 0.4 1 8.6 - 3 8.7 0.3
Deadman Creek Deadman-6 6 37.5 9.8 5 42.8 17.1 11 39.9 13.1
Deadman-5 5 31.5 3.0 5 27.2 1.5 10 29.4 3.2
Deadman-4 5 37.3 9.4 5 27.4 2.9 5 38.6 4.1 15 34.4 7.7
Deadman-3 6 29.6 4.6 5 26.8 4.7 1 24.3 - 6 24.9 3.8 2 22.2 0.9 20 26.5 4.5
Deadman-1 1 22.6 - 1 27.3 - 1 26.9 - 3 25.6 2.6
Total1 3 1.4 0.5 3 10.3 5.0 112 19.2 11.0 59 9.2 10.3 2 13.2 15.7 8 2.9 1.2 46 9.0 8.1 72 21.2 14.4 143 22.7 19.1 209 21.6 21.4 657 19.0 17.6
1Total number of measurements (n) and group mean (SD) for each mesohabitat type per River Segment.
2Total number of measurement (n) and group mean (SD) for each geomorphic reach.
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 46 October 2015
Table 5.1-4. Mean (±SD) wetted width (m) of mesohabitats in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 29.0 7.3 2 57.1 2.1 8 23.0 11.5 15 28.9 17.8 30 29.3 16.0
Oshetna-2 3 47.1 2.3 2 63.4 3.5 1 39.4 - 6 51.2 10.1
Oshetna-1 5 34.0 5.3 2 38.4 16.5 5 51.6 3.9 5 41.9 3.4 17 42.0 9.0
Black River Black-3 5 26.6 2.1 2 19.1 0.8 5 26.3 5.0 5 25.5 3.3 17 25.3 4.0
Black-2 7 20.4 7.9 1 18.3 - 3 14.2 8.5 6 17.0 4.8 17 18.0 6.7
Black-1 4 21.5 7.0 1 17.9 - 5 33.6 35.3 5 18.8 4.0 15 24.4 20.4
Goose Creek Goose-3 5 13.2 3.7 1 14.9 - 6 12.2 3.5 12 12.8 3.3
Goose-2 5 17.6 2.7 3 19.0 5.2 5 14.3 1.3 13 16.7 3.4
Goose-1 7 14.9 2.9 1 11.2 - 5 11.4 1.9 5 11.9 2.4 18 12.9 2.8
Proposed reservoir full pool
Unnamed 230.2 NA 1 1.1 - 1 1.1 -
Unnamed 230.1 NA 3 2.7 0.5 3 2.2 0.5 1 2.6 - 7 2.5 0.5
Unnamed 228.5 NA 3 9.2 1.2 5 8.0 0.5 1 9.9 - 3 6.4 0.9 12 8.0 1.4
Unnamed 226.2 NA 1 2.5 - 1 2.5 -
Unnamed 219.6 NA 4 3.1 0.9 4 3.1 0.9
Unnamed 214.4 NA 1 1.8 - 1 1.8 -
Jay Creek Jay-4 1 0.9 - 5 5.2 0.5 5 7.9 1.7 6 5.3 1.8 17 5.8 2.2
Jay-3 5 10.8 1.0 3 3.8 2.8 2 5.9 5.8 7 6.4 3.8 17 7.2 3.9
Jay-2 5 11.4 1.9 6 10.1 1.2 4 11.6 0.9 5 10.2 1.6 20 10.7 1.5
Jay-1 3 8.0 4.4 1 5.0 - 1 1.0 - 2 4.0 1.4 1 7.2 - 11 8.5 2.8 15 7.4 3.2 34 7.3 3.3
Tsisi Creek Tsisi-2 5 16.1 3.1 5 14.1 2.7 10 15.1 3.0
Tsisi-1 8 14.1 6.4 6 14.4 4.1 1 4.7 - 15 13.6 5.7
Kosina Creek Kosina-3 2 1.4 0.1 1 3.0 - 3 57.7 53.1 19 47.6 40.6 25 43.3 41.5
Kosina-2 1 34.0 - 2 1.7 0.4 1 11.0 - 5 32.3 9.3 17 28.6 12.3 16 21.0 13.9 42 24.6 13.8
Kosina-1 2 11.5 3.5 14 20.8 13.6 13 16.9 8.6 29 18.4 11.2
Unnamed 208.6 NA 1 2.0 - 1 2.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 0.8 0.4 6 0.8 0.4
Unnamed 206.3 206.3-3 1 1.2 - 2 1.4 0.6 1 1.2 - 4 1.3 0.4
206.3-1 4 3.5 0.2 6 3.3 1.1 1 2.5 - 1 2.5 - 12 3.2 0.8
Unnamed 204.5 204.5-2 1 5.2 - 1 5.2 -
204.5-1 3 2.9 1.4 7 4.5 2.0 1 0.6 - 1 1.3 - 12 3.5 2.1
Unnamed 198.9 NA 1 2.0 - 1 2.0 -
Unnamed 198.4 LB-1 NA 1 2.1 - 1 2.1 -
Unnamed 197.7 197.7-3 2 3.4 0.9 2 3.1 0.1 4 3.2 0.5
197.7-2 3 4.1 0.9 1 2.6 - 4 3.7 1.0
197.7-1 2 7.2 1.6 3 6.6 0.8 2 3.5 2.9 3 6.9 0.6 1 6.0 - 1 4.8 - 12 6.0 1.8
Unnamed 197.7 RB-1 NA 3 3.6 2.0 1 4.8 - 4 3.9 1.8
Watana Creek Trib Watana Trib-2 3 2.1 0.5 2 2.2 0.1 5 2.3 0.4 10 2.2 0.4
Watana Trib-1 1 0.8 - 1 9.1 - 2 5.0 1.0 2 14.2 5.0 8 10.6 2.1 14 9.5 4.2
Watana Creek LB-1.1.1 NA 1 4.7 - 2 1.0 0.1 2 1.2 0.6 5 1.8 1.6
Watana Creek RB-1 NA 2 1.2 0.8 1 0.9 - 4 0.9 0.3 4 0.9 0.4 11 0.9 0.4
Watana Creek Watana-3 2 1.2 0.2 13 11.6 5.9 3 8.5 1.6 4 12.8 5.8 7 7.8 2.5 29 9.8 5.4
Watana-2 2 11.4 0.7 2 1.3 0.4 1 7.1 - 2 10.2 1.1 6 6.6 4.5 5 10.4 1.3 18 8.0 4.0
Watana-1 1 14.0 - 1 14.7 - 2 1.4 0.2 6 7.7 3.6 17 16.2 7.1 12 12.7 5.1 39 13.0 6.8
Unnamed 194.8 194.8-4 6 3.1 0.9 4 2.6 0.5 10 2.9 0.8
194.8-3 2 5.1 0.5 2 3.2 0.8 2 3.6 0.2 9 3.9 0.8 3 2.6 0.5 1 2.6 - 6 3.2 0.7 25 3.5 0.9
194.8-1 2 5.9 0.2 1 7.4 - 3 6.4 0.9
Deadman Creek Deadman-6 6 36.9 9.5 5 42.6 17.4 11 39.5 13.2
Deadman-5 5 29.7 3.2 5 24.6 2.8 10 27.1 3.9
Deadman-4 5 36.3 9.1 5 25.4 2.4 5 37.9 3.6 15 33.2 7.9
Deadman-3 6 28.0 4.6 5 23.3 5.0 1 18.3 - 6 24.0 4.2 2 18.2 1.0 20 24.2 5.1
Deadman-1 1 18.0 - 1 15.7 - 1 21.0 - 3 18.3 2.7
Total1 3 1.1 0.2 3 8.1 5.1 112 17.2 10.6 59 6.9 7.9 2 10.2 11.4 10 1.3 0.3 47 5.5 3.8 72 18.2 13.6 143 19.6 18.0 214 18.0 19.5 665 16.0 16.1
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 47 October 2015
Table 5.1-5. Mean (±SD) bankfull depth (m) of mesohabitats in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 0.9 0.2 6 0.7 0.2 7 0.9 0.3 18 0.9 0.2
Oshetna-2
Oshetna-1 5 0.7 0.4 4 0.6 0.2 2 1.1 0.5 11 0.8 0.3
Black River Black-3 5 0.7 0.4 2 0.8 0.2 5 0.8 0.1 5 0.7 0.2 17 0.7 0.2
Black-2 7 0.7 0.2 1 0.2 - 3 0.6 0.2 6 1.0 0.4 17 0.8 0.4
Black-1 4 0.5 0.2 1 2.1 - 5 1.0 0.5 5 1.0 0.3 15 1.0 0.5
Goose Creek Goose-3 5 1.0 0.4 1 0.5 - 6 0.7 0.1 12 0.8 0.3
Goose-2 5 0.6 0.3 3 0.7 0.1 5 1.0 0.1 13 0.7 0.3
Goose-1 7 1.0 0.4 1 1.3 - 5 0.6 0.1 5 0.8 0.4 18 0.8 0.4
Proposed reservoir full pool
Unnamed 230.2 NA 1 0.5 - 1 0.5 -
Unnamed 230.1 NA 3 0.7 0.1 3 0.5 0.1 1 0.5 - 7 0.6 0.1
Unnamed 228.5 NA 3 0.8 0.2 5 0.8 0.4 1 1.3 - 3 0.6 0.4 12 0.8 0.4
Unnamed 226.2 NA
Unnamed 219.6 NA 4 0.7 0.2 4 0.7 0.2
Unnamed 214.4 NA 1 0.9 - 1 0.9 -
Jay Creek Jay-4 1 0.3 - 5 0.9 0.2 5 0.7 0.4 6 0.7 0.2 17 0.7 0.3
Jay-3 5 0.6 0.2 2 0.9 0.4 7 0.7 0.3
Jay-2 5 0.7 0.2 6 0.6 0.3 2 0.6 0.1 2 0.5 0.1 15 0.6 0.2
Jay-1 3 1.0 0.2 1 1.0 - 1 0.5 - 5 0.9 0.2
Tsisi Creek Tsisi-2 5 0.8 0.3 5 0.7 0.1 10 0.8 0.2
Tsisi-1 8 0.7 0.3 6 0.6 0.1 1 0.6 - 15 0.6 0.2
Kosina Creek Kosina-3
Kosina-2 1 0.7 - 5 0.6 0.2 6 0.6 0.2
Kosina-1 2 1.0 0.4 2 1.0 0.4
Unnamed 208.6 NA 1 0.6 - 1 0.6 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 0.4 0.1 6 0.4 0.1
Unnamed 206.3 206.3-3 1 1.0 - 2 1.0 0.2 1 1.2 - 4 1.1 0.1
206.3-1 4 0.8 0.1 6 1.0 0.2 1 0.8 - 1 1.2 - 12 0.9 0.2
Unnamed 204.5 204.5-2 1 1.0 - 1 1.0 -
204.5-1 3 0.6 0.0 7 1.2 1.0 1 0.3 - 1 0.4 - 12 0.9 0.8
Unnamed 198.9 NA 1 0.4 - 1 0.4 -
Unnamed 198.4 LB-1 NA 1 0.3 - 1 0.3 -
Unnamed 197.7 197.7-3 2 0.9 0.4 2 0.6 0.1 4 0.8 0.3
197.7-2 3 2.2 1.4 1 0.6 - 4 1.8 1.4
197.7-1 2 1.1 0.4 3 1.2 0.4 2 0.7 0.3 3 0.7 0.1 1 0.4 - 1 1.2 - 12 0.9 0.4
Unnamed 197.7 RB-1 NA 3 0.8 0.2 1 0.6 - 4 0.8 0.2
Watana Creek Trib Watana Trib-2 3 0.8 0.1 2 0.5 0.0 5 0.6 0.2 10 0.6 0.2
Watana Trib-1 1 0.8 - 1 1.3 - 2 0.5 0.4 2 0.4 0.3 8 0.9 0.3 14 0.8 0.4
Watana Cr. LB-1.1.1 NA 1 1.0 - 2 0.6 0.2 2 0.6 0.0 5 0.7 0.2
Watana Cr. RB-1 NA 2 0.3 0.0 1 0.3 - 4 0.2 0.1 4 0.3 0.2 11 0.3 0.1
Watana Creek Watana-3 2 0.4 0.2 13 0.6 0.2 3 0.7 0.1 4 0.5 0.1 7 0.6 0.3 29 0.6 0.2
Watana-2 2 0.8 0.1 1 1.3 - 2 0.8 0.7 1 0.6 - 3 1.3 0.5 9 1.0 0.5
Watana-1 1 0.8 - 1 0.6 - 5 1.3 1.1 4 0.9 0.3 2 1.0 0.3 13 1.0 0.7
Unnamed 194.8 194.8-4 6 1.2 0.2 4 0.8 0.5 10 1.1 0.4
194.8-3 2 1.4 0.2 2 0.9 0.2 2 1.7 0.0 9 1.7 0.2 3 1.5 0.3 1 0.9 - 6 0.7 0.3 25 1.3 0.5
194.8-1 2 0.9 0.2 1 1.0 - 3 0.9 0.1
Deadman Creek Deadman-6 6 0.8 0.4 5 0.9 0.1 11 0.9 0.3
Deadman-5 5 0.5 0.2 5 0.9 0.3 10 0.7 0.3
Deadman-4 5 0.7 0.3 5 0.6 0.1 5 1.0 0.1 15 0.8 0.2
Deadman-3 6 0.7 0.3 5 1.0 0.2 1 0.9 - 6 0.8 0.2 2 2.6 1.9 20 1.0 0.7
Deadman-1 1 0.8 - 1 3.6 - 1 0.7 - 3 1.7 1.7
Total1 3 0.4 0.1 3 1.2 0.4 112 0.7 0.3 56 0.9 0.6 2 0.6 0.4 1 0.8 - 40 1.2 0.7 65 0.7 0.3 71 0.7 0.3 120 0.8 0.4 473 0.8 0.4
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 48 October 2015
Table 5.1-6. Mean (±SD) thalweg depth (m) of mesohabitats in Upper River tributaries.
Tributary Name Geomorphic Reach Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 0.6 0.3 6 0.5 0.3 7 0.7 0.2 18 0.6 0.2
Oshetna-2
Oshetna-1 5 0.5 0.3 4 0.5 0.3 2 0.5 0.1 11 0.5 0.3
Black River Black-3 5 0.6 0.3 2 0.8 0.2 5 0.6 0.2 5 0.7 0.3 17 0.7 0.2
Black-2 7 0.7 0.2 1 0.2 - 3 0.6 0.3 6 0.6 0.3 17 0.6 0.3
Black-1 4 0.5 0.1 1 0.3 - 5 0.7 0.2 5 0.9 0.2 15 0.6 0.3
Goose Creek Goose-3 5 0.6 0.3 1 0.2 - 6 0.5 0.2 12 0.5 0.3
Goose-2 5 0.5 0.2 3 0.5 0.1 5 0.7 0.3 13 0.6 0.2
Goose-1 7 0.7 0.4 1 0.7 - 5 0.5 0.2 5 0.5 0.3 18 0.6 0.3
Proposed reservoir full pool
Unnamed 230.2 NA 1 0.1 - 1 0.1 -
Unnamed 230.1 NA 3 0.3 0.0 3 0.3 0.0 1 0.2 - 7 0.3 0.1
Unnamed 228.5 NA 3 0.5 0.0 5 0.5 0.2 1 1.3 - 3 0.5 0.4 12 0.6 0.3
Unnamed 226.2 NA
Unnamed 219.6 NA 4 0.4 0.3 4 0.4 0.3
Unnamed 214.4 NA 1 0.2 - 1 0.2 -
Jay Creek Jay-4 1 0.3 - 5 0.9 0.3 5 0.4 0.2 6 0.5 0.4 17 0.6 0.4
Jay-3 5 0.6 0.2 3 0.5 0.4 2 0.4 0.0 10 0.5 0.2
Jay-2 5 0.5 0.3 6 0.5 0.3 2 0.4 0.3 2 0.4 0.3 15 0.5 0.3
Jay-1 3 0.9 0.2 2 0.5 0.2 1 0.7 - 1 0.5 - 7 0.7 0.2
Tsisi Creek Tsisi-2 5 0.7 0.3 5 0.6 0.2 10 0.6 0.2
Tsisi-1 8 0.7 0.3 6 0.6 0.2 1 0.4 - 15 0.6 0.2
Kosina Creek Kosina-3 2 0.7 0.2 2 0.7 0.2
Kosina-2 1 0.3 - 5 0.5 0.2 6 0.4 0.2
Kosina-1 2 0.7 0.4 2 0.7 0.4
Unnamed 208.6 NA 1 0.2 - 1 0.2 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 0.1 0.0 6 0.1 0.0
Unnamed 206.3 206.3-3 1 0.3 - 2 0.4 0.5 1 0.5 - 4 0.4 0.3
206.3-1 4 0.4 0.1 6 0.4 0.2 1 0.2 - 1 0.5 - 12 0.4 0.2
Unnamed 204.5 204.5-2 1 0.6 - 1 0.6 -
204.5-1 3 0.3 0.2 7 0.7 0.6 1 0.3 - 1 0.4 - 12 0.5 0.5
Unnamed 198.9 NA 1 0.3 - 1 0.3 -
Unnamed 198.4 LB-1 NA 1 0.2 - 1 0.2 -
Unnamed 197.7 197.7-3 2 0.7 0.1 2 0.6 0.1 4 0.7 0.1
197.7-2 3 1.0 0.6 1 0.6 - 4 0.9 0.5
197.7-1 2 0.7 0.1 3 0.5 0.2 2 0.3 0.1 3 0.4 0.2 1 0.4 - 1 0.3 - 12 0.5 0.2
Unnamed 197.7 RB-1 NA 3 0.6 0.1 1 0.6 - 4 0.6 0.1
Watana Creek Trib Watana Trib-2 3 0.6 0.4 2 0.5 0.0 5 0.4 0.2 10 0.5 0.3
Watana Trib-1 1 0.4 - 1 0.4 - 2 0.5 0.4 2 0.3 0.4 8 0.6 0.3 14 0.5 0.3
Watana Cr. LB-1.1.1 NA 1 0.3 - 2 0.6 0.2 2 0.5 0.2 5 0.5 0.2
Watana Cr. RB-1 NA 2 0.2 0.0 1 0.1 - 4 0.2 0.1 4 0.2 0.1 11 0.2 0.1
Watana Creek Watana-3 2 0.3 0.1 13 0.5 0.2 3 0.7 0.1 4 0.5 0.2 7 0.6 0.3 29 0.5 0.2
Watana-2 2 0.8 0.1 1 0.6 - 2 0.4 0.2 1 0.4 - 3 0.6 0.2 9 0.6 0.2
Watana-1 1 0.8 - 1 0.5 - 6 0.6 0.3 4 0.9 0.3 2 0.7 0.0 14 0.7 0.3
Unnamed 194.8 194.8-4 6 0.4 0.2 4 0.5 0.3 10 0.5 0.3
194.8-3 2 0.5 0.5 2 0.6 0.0 2 0.9 0.1 9 0.6 0.4 3 0.6 0.1 1 0.3 - 6 0.6 0.3 25 0.6 0.3
194.8-1 2 0.7 0.4 1 0.2 - 3 0.5 0.4
Deadman Creek Deadman-6 6 0.5 0.2 5 0.6 0.3 11 0.6 0.3
Deadman-5 5 0.5 0.2 5 0.8 0.3 10 0.7 0.3
Deadman-4 5 0.6 0.2 5 0.6 0.1 5 0.8 0.2 15 0.7 0.2
Deadman-3 6 0.5 0.1 5 0.7 0.3 1 0.2 - 6 0.8 0.2 2 0.5 0.1 20 0.6 0.2
Deadman-1 1 0.3 - 1 0.2 - 1 0.7 - 3 0.4 0.3
Total1 3 0.3 0.1 3 0.6 0.4 112 0.6 0.3 56 0.5 0.4 2 0.2 0.0 1 0.4 - 48 0.5 0.3 65 0.6 0.2 71 0.5 0.3 120 0.6 0.3 481 0.5 0.3
1 Total number of measurements (n) and group mean (SD) for each mesohabitat type per River Segment.
2 Total number of measurements (n) and group mean (SD) for each geomorphic reach.
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 49 October 2015
Table 5.1-7. Mean (±SD) max pool and crest depths (m) of Beaver Pond and Pool mesohabitats in Upper River tributaries.
Tributary Name Geomorphic Reach
Average Max Pool Depth Average Pool Crest Depth
Beaver Pond Pool All Units2 Pool All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3
Oshetna River Oshetna-2
Oshetna River Oshetna-1
Black River Black-3
Black River Black-2
Black River Black-1 1 2.5 - 1 2.5 - 1 0.5 - 1 0.5 -
Goose Creek Goose-3
Goose Creek Goose-2
Goose Creek Goose-1
Proposed reservoir full pool
Unnamed 230.2 NA
Unnamed 230.1 NA 3 0.6 0.2 3 0.6 0.2 3 0.2 0.0 3 0.2 0.0
Unnamed 228.5 NA
Unnamed 226.2 NA
Unnamed 219.6 NA
Unnamed 214.4 NA
Jay Creek Jay-4 5 1.0 0.2 5 1.0 0.2 5 0.2 0.1 5 0.2 0.1
Jay Creek Jay-3 3 0.8 0.4 3 0.8 0.4 2 0.3 0.2 2 0.3 0.2
Jay Creek Jay-2
Jay Creek Jay-1 2 0.6 0.1 2 0.6 0.1 1 0.3 - 1 0.3 -
Tsisi Creek Tsisi-2
Tsisi Creek Tsisi-1
Kosina Creek Kosina-3 2 0.7 0.2 2 0.7 0.2 2 0.3 0.1 2 0.3 0.1
Kosina Creek Kosina-2 1 2.0 - 1 2.0 -
Kosina Creek Kosina-1 2 0.7 0.0 2 0.7 0.0 2 0.3 0.0 2 0.3 0.0
Unnamed 208.6 NA
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA
Unnamed 206.3 206.3-3
Unnamed 206.3 206.3-1
Unnamed 204.5 204.5-2
Unnamed 204.5 204.5-1
Unnamed 198.9 NA
Unnamed 198.4 LB-1 NA
Unnamed 197.7 197.7-3
Unnamed 197.7 197.7-2
Unnamed 197.7 197.7-1 2 0.7 0.4 2 0.7 0.4 2 0.2 0.1 2 0.2 0.1
Unnamed 197.7 RB-1 NA
Watana Creek Trib Watana Trib-2
Watana Creek Trib Watana Trib-1 1 1.1 - 1 1.1 - 1 0.6 - 1 0.6 -
Watana Creek LB-1.1.1 NA 1 1.4 - 1 1.4 - 1 0.4 - 1 0.4 -
Watana Creek RB-1 NA 1 0.6 - 1 0.6 - 1 0.2 - 1 0.2 -
Watana Creek Watana-3
Watana Creek Watana-2 1 1.3 - 1 1.3 - 1 0.5 - 1 0.5 -
Watana Creek Watana-1 1 0.7 - 6 0.9 0.5 7 0.9 0.5 5 0.3 0.2 5 0.3 0.2
Unnamed 194.8 194.8-4 6 0.8 0.1 6 0.8 0.1 5 0.2 0.1 5 0.2 0.1
Unnamed 194.8 194.8-3 1 1.8 - 9 1.2 0.1 10 1.3 0.2 9 0.6 0.2 9 0.6 0.2
Unnamed 194.8 194.8-1 1 1.0 - 1 1.0 - 1 0.4 - 1 0.4 -
Deadman Creek Deadman-6
Deadman Creek Deadman-5
Deadman Creek Deadman-4 1 1.0 - 1 1.0 -
Deadman Creek Deadman-3 1 1.2 -
Deadman Creek Deadman-1 1 6.0 - 1 6.0 - 1 1.2 - 1 1.2 -
Total1 2 1.3 0.8 48 1.1 0.8 51 1.1 0.8 43 0.4 0.2 45 0.4 0.3
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 50 October 2015
Table 5.1-8. Mean (±SD) percent erosion along mesohabitat units in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 1.0 2.2 2 32.5 24.7 8 9.4 15.2 15 13.0 13.6 30 11.3 14.8
Oshetna-2 3 15.0 10.0 1 0.0 - 1 0.0 - 5 9.0 10.8
Oshetna-1 5 13.0 16.4 2 5.0 7.1 5 2.0 2.7 5 15.8 9.3 17 9.6 11.4
Black River Black-3 5 0.0 0.0 2 0.0 0.0 5 0.0 0.0 5 1.0 2.2 17 0.3 1.2
Black-2 7 0.0 0.0 1 0.0 - 3 0.0 0.0 6 0.0 0.0 17 0.0 0.0
Black-1 4 0.0 0.0 1 0.0 - 5 0.0 0.0 5 0.0 0.0 15 0.0 0.0
Goose Creek Goose-3 5 0.0 0.0 1 0.0 - 6 0.0 0.0 12 0.0 0.0
Goose-2 5 0.0 0.0 3 0.0 0.0 5 0.0 0.0 13 0.0 0.0
Goose-1 7 8.6 11.1 1 0.0 - 5 14.0 20.7 5 23.0 20.2 18 13.6 17.0
Proposed reservoir full pool
Unnamed 230.2 NA 1 25.0 - 1 25.0 -
Unnamed 230.1 NA 3 0.0 0.0 3 0.0 0.0 1 0.0 - 7 0.0 0.0
Unnamed 228.5 NA 3 16.7 28.9 5 0.0 0.0 1 0.0 - 3 0.0 0.0 12 4.2 14.4
Unnamed 226.2 NA
Unnamed 219.6 NA 4 13.8 9.5 4 13.8 9.5
Unnamed 214.4 NA 1 0.0 - 1 0.0 -
Jay Creek Jay-4 1 0.0 - 5 0.0 0.0 5 1.0 2.2 6 0.0 0.0 17 0.3 1.2
Jay-3 5 0.0 0.0 3 8.3 14.4 2 0.0 0.0 7 7.1 7.6 17 4.4 7.9
Jay-2 5 3.0 6.7 6 1.7 4.1 4 5.0 4.1 5 14.0 15.2 20 5.8 9.5
Jay-1 3 1.7 2.9 1 0.0 - 1 50.0 - 2 0.0 0.0 1 0.0 - 11 7.3 11.0 15 0.8 2.6 34 4.3 10.7
Tsisi Creek Tsisi-2 5 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Tsisi-1 8 0.0 0.0 6 0.0 0.0 1 0.0 - 15 0.0 0.0
Kosina Creek Kosina-3 2 7.5 10.6 2 15.0 14.1 4 0.0 0.0 26 4.4 9.9 34 4.7 9.7
Kosina-2 1 5.0 - 2 0.0 0.0 1 0.0 - 5 12.0 16.8 17 1.8 3.5 16 1.6 3.0 42 2.9 6.9
Kosina-1 2 0.0 0.0 14 0.0 0.0 13 0.8 2.8 29 0.3 1.9
Unnamed 208.6 NA 1 50.0 - 1 50.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 11.7 13.9 6 11.7 13.9
Unnamed 206.3 206.3-3 1 0.0 - 2 0.0 0.0 1 0.0 - 4 0.0 0.0
206.3-1 4 0.0 0.0 6 0.0 0.0 1 0.0 - 1 0.0 - 12 0.0 0.0
Unnamed 204.5 204.5-2 1 0.0 - 1 0.0 -
204.5-1 3 0.0 0.0 7 4.3 5.5 1 0.0 - 1 0.0 - 12 2.5 4.6
Unnamed 198.9 NA 1 0.0 - 1 0.0 -
Unnamed 198.4 LB-1 NA 1 12.5 - 1 12.5 -
Unnamed 197.7 197.7-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0
197.7-2 3 6.7 2.9 1 0.0 - 4 5.0 4.1
197.7-1 2 25.0 7.1 3 6.7 2.9 2 15.0 0.0 3 11.7 7.6 1 12.5 - 1 15.0 - 12 13.5 7.4
Unnamed 197.7 RB-1 NA 3 13.3 15.3 1 10.0 - 4 12.5 12.6
Watana Creek Trib Watana Trib-2 3 0.0 0.0 2 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Watana Trib-1 1 0.0 - 1 40.0 - 2 15.0 21.2 2 18.8 26.5 8 6.9 13.9 14 11.6 17.0
Watana Cr. LB-1.1.1 NA 1 15.0 - 2 0.0 0.0 2 5.0 7.1 5 5.0 7.1
Watana Cr. RB-1 NA 3 20.0 20.0 1 0.0 - 4 17.5 23.6 4 22.5 45.0 12 18.3 28.6
Watana Creek Watana-3 2 0.0 0.0 13 0.0 0.0 3 0.0 0.0 4 0.0 0.0 7 2.9 7.6 29 0.7 3.7
Watana-2 2 0.0 0.0 2 0.0 0.0 1 50.0 - 2 27.5 38.9 6 1.7 4.1 5 9.5 19.9 18 9.0 19.1
Watana-1 1 2.5 - 1 65.0 - 2 0.0 0.0 6 20.8 40.1 17 21.8 31.9 12 16.3 23.7 39 19.4 29.8
Unnamed 194.8 194.8-4 6 72.5 35.9 4 63.8 20.6 10 69.0 29.6
194.8-3 2 25.0 21.2 2 85.0 14.1 2 0.0 0.0 9 21.7 43.0 3 0.0 0.0 1 0.0 - 6 0.0 0.0 25 16.6 34.5
194.8-1 2 2.5 3.5 1 5.0 - 3 3.3 2.9
Deadman Creek Deadman-6 6 0.0 0.0 5 0.0 0.0 11 0.0 0.0
Deadman-5 5 1.0 2.2 5 10.0 10.0 10 5.5 8.3
Deadman-4 5 0.0 0.0 5 0.0 0.0 4 8.1 14.7 14 2.3 8.0
Deadman-3 6 0.0 0.0 5 5.0 7.1 1 100.0 - 6 15.0 32.1 2 7.5 10.6 20 11.5 27.5
Deadman-1 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Total1 3 0.0 0.0 3 17.5 19.8 112 4.0 14.0 59 6.7 12.3 2 56.3 61.9 10 6.5 16.0 48 19.8 34.2 72 7.4 15.2 143 5.4 14.6 220 6.4 14.9 672 7.0 17.4
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 51 October 2015
Table 5.1-9. Mean (±SD) percent undercut banks along mesohabitat units in Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 1.0 2.2 2 5.0 7.1 8 1.9 3.7 15 1.0 2.8 30 1.5 3.3
Oshetna-2 3 0.0 0.0 1 10.0 - 1 15.0 - 5 5.0 7.1
Oshetna-1 5 0.0 0.0 2 0.0 0.0 5 1.0 2.2 5 4.4 8.8 17 1.6 4.9
Black River Black-3 5 0.0 0.0 2 0.0 0.0 5 0.0 0.0 5 0.0 0.0 17 0.0 0.0
Black-2 7 0.0 0.0 1 0.0 - 3 0.0 0.0 6 0.0 0.0 17 0.0 0.0
Black-1 4 0.0 0.0 1 0.0 - 5 0.0 0.0 5 0.0 0.0 15 0.0 0.0
Goose Creek Goose-3 5 0.0 0.0 1 0.0 - 6 1.7 4.1 12 0.8 2.9
Goose-2 5 0.0 0.0 3 13.3 23.1 5 0.0 0.0 13 3.1 11.1
Goose-1 7 0.0 0.0 1 0.0 - 5 0.0 0.0 5 0.0 0.0 18 0.0 0.0
Proposed reservoir full pool
Unnamed 230.2 NA 1 25.0 - 1 25.0 -
Unnamed 230.1 NA 3 0.0 0.0 3 0.0 0.0 1 0.0 - 7 0.0 0.0
Unnamed 228.5 NA 3 0.0 0.0 5 0.0 0.0 1 0.0 - 3 0.0 0.0 12 0.0 0.0
Unnamed 226.2 NA
Unnamed 219.6 NA 4 7.5 6.5 4 7.5 6.5
Unnamed 214.4 NA 1 0.0 - 1 0.0 -
Jay Creek Jay-4 1 0.0 - 5 3.0 6.7 5 0.0 0.0 6 0.0 0.0 17 0.9 3.6
Jay-3 5 0.0 0.0 3 6.7 7.6 2 0.0 0.0 7 5.0 9.6 17 3.2 7.1
Jay-2 5 0.0 0.0 6 0.0 0.0 4 1.3 2.5 5 2.0 4.5 20 0.8 2.4
Jay-1 3 0.0 0.0 1 0.0 - 1 0.0 - 2 37.5 3.5 1 0.0 - 11 4.5 9.1 15 3.8 10.4 34 5.4 11.8
Tsisi Creek Tsisi-2 5 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Tsisi-1 8 0.0 0.0 6 0.0 0.0 1 0.0 - 15 0.0 0.0
Kosina Creek Kosina-3 2 5.0 7.1 2 7.5 10.6 4 6.3 6.3 26 10.3 20.9 34 9.3 18.5
Kosina-2 1 0.0 - 2 0.0 0.0 1 0.0 - 5 1.0 2.2 17 1.5 3.4 16 5.0 9.5 42 2.6 6.5
Kosina-1 2 0.0 0.0 14 0.7 1.9 13 0.4 0.9 29 0.5 1.4
Unnamed 208.6 NA 1 0.0 - 1 0.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 0.0 0.0 6 0.0 0.0
Unnamed 206.3 206.3-3 1 10.0 - 2 0.0 0.0 1 0.0 - 4 2.5 5.0
206.3-1 4 28.8 16.5 6 41.7 30.8 1 40.0 - 1 55.0 - 12 38.3 23.9
Unnamed 204.5 204.5-2 1 0.0 - 1 0.0 -
204.5-1 3 0.0 0.0 7 12.5 22.9 1 0.0 - 1 0.0 - 12 7.3 18.1
Unnamed 198.9 NA 1 0.0 - 1 0.0 -
Unnamed 198.4 LB-1 NA 1 0.0 - 1 0.0 -
Unnamed 197.7 197.7-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0
197.7-2 3 1.7 2.9 1 0.0 - 4 1.3 2.5
197.7-1 2 13.8 1.8 3 5.0 0.0 2 17.5 10.6 3 6.7 5.8 1 12.5 - 1 25.0 - 12 11.3 7.7
Unnamed 197.7 RB-1 NA 3 10.0 10.0 1 0.0 - 4 7.5 9.6
Watana Creek Trib Watana Trib-2 3 0.0 0.0 2 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Watana Trib-1 1 0.0 - 1 0.0 - 2 5.0 7.1 2 2.5 3.5 8 3.1 7.0 14 2.9 5.8
Watana Cr. LB-1.1.1 NA 1 25.0 - 2 0.0 0.0 2 0.0 0.0 5 5.0 11.2
Watana Cr. RB-1 NA 3 0.0 0.0 1 0.0 - 4 0.0 0.0 4 0.0 0.0 12 0.0 0.0
Watana Creek Watana-3 2 0.0 0.0 13 1.9 3.8 3 0.0 0.0 4 0.0 0.0 7 4.3 6.1 29 1.9 4.1
Watana-2 2 0.0 0.0 2 0.0 0.0 1 45.0 - 2 5.0 7.1 6 0.0 0.0 5 2.0 4.5 18 3.6 10.8
Watana-1 1 0.0 - 1 0.0 - 2 2.5 3.5 6 1.7 4.1 17 2.8 6.8 12 2.3 4.9 39 2.3 5.5
Unnamed 194.8 194.8-4 6 19.2 28.4 4 13.8 14.4 10 17.0 22.9
194.8-3 2 15.0 7.1 2 47.5 17.7 2 30.0 28.3 9 51.1 29.7 3 63.3 20.8 1 25.0 - 6 28.3 24.8 25 41.2 27.0
194.8-1 2 6.3 1.8 1 0.0 - 3 4.2 3.8
Deadman Creek Deadman-6 6 0.0 0.0 5 0.0 0.0 11 0.0 0.0
Deadman-5 5 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Deadman-4 5 0.0 0.0 5 0.0 0.0 4 0.0 0.0 14 0.0 0.0
Deadman-3 6 0.0 0.0 5 1.0 2.2 1 0.0 - 6 0.0 0.0 2 0.0 0.0 20 0.3 1.1
Deadman-1 1 0.0 - 1 5.0 - 1 0.0 - 3 1.7 2.9
Total1 3 0.0 0.0 3 10.0 10.0 112 2.5 9.0 59 8.9 18.7 2 0.0 0.0 10 1.5 3.4 48 17.1 25.2 72 3.4 13.3 143 2.1 5.9 220 4.2 11.5 672 4.7 13.2
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 52 October 2015
Table 5.1-10. Mean (±SD) LWD count in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of
LWD
Oshetna River Oshetna-3 5 0 2 12 8 3 15 7 30 22
Oshetna-2 3 6 1 0 1 0 5 6
Oshetna-1 5 9 2 2 5 3 5 8 17 22
Black River Black-3 5 0 2 0 5 0 5 0 17 0
Black-2 7 0 1 0 3 0 6 2 17 2
Black-1 4 0 1 0 5 18 5 0 15 18
Goose Creek Goose-3 5 0 1 0 6 0 12 0
Goose-2 5 1 3 0 5 1 13 2
Goose-1 7 6 1 0 5 4 5 7 18 17
Proposed reservoir full pool
Unnamed 230.2 NA 1 13 1 13
Unnamed 230.1 NA 3 16 3 1 1 1 7 18
Unnamed 228.5 NA 3 10 5 18 1 1 3 16 12 45
Unnamed 226.2 NA
Unnamed 219.6 NA 4 41 4 41
Unnamed 214.4 NA 1 17 1 17
Jay Creek Jay-4 1 0 5 0 5 0 6 0 17 0
Jay-3 5 0 3 0 2 0 7 2 17 2
Jay-2 5 10 6 5 4 8 5 0 20 23
Jay-1 3 2 1 0 1 0 2 0 1 0 11 0 15 0 34 2
Tsisi Creek Tsisi-2 5 0 5 0 10 0
Tsisi-1 8 0 6 0 1 0 15 0
Kosina Creek Kosina-3 2 0 2 0 4 0 26 0 34 0
Kosina-2 1 0 2 0 1 0 5 1 17 0 16 0 42 1
Kosina-1 2 0 14 0 13 0 29 0
Unnamed 208.6 NA 1 11 1 11
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 37 6 37
Unnamed 206.3 206.3-3 1 1 2 5 1 0 4 6
206.3-1 4 9 6 37 1 13 1 4 12 63
Unnamed 204.5 204.5-2 1 11 1 11
204.5-1 3 27 7 59 1 1 1 2 12 89
Unnamed 198.9 NA 1 0 1 0
Unnamed 198.4 LB-1 NA 1 5 1 5
Unnamed 197.7 197.7-3 2 0 2 0 4 0
197.7-2 3 27 1 7 4 34
197.7-1 2 6 3 32 2 1 3 48 1 3 1 6 12 96
Unnamed 197.7 RB-1 NA 3 39 1 0 4 39
Watana Creek Trib Watana Trib-2 3 0 2 0 5 0 10 0
Watana Trib-1 1 0 1 0 2 5 2 0 8 5 14 10
Watana Cr. LB-1.1.1 NA 1 19 2 0 2 0 5 19
Watana Cr. RB-1 NA 3 1 1 0 4 2 4 1 12 4
Watana Creek Watana-3 2 0 13 3 3 1 4 1 7 0 29 5
Watana-2 2 7 2 0 1 1 2 2 6 2 5 5 18 17
Watana-1 1 0 1 5 2 0 6 76 17 143 12 14 39 238
Unnamed 194.8 194.8-4 5 7 3 0 8 7
194.8-3 2 13 2 0 2 0 9 22 3 4 1 0 6 10 25 49
194.8-1 2 28 1 16 3 44
Deadman Creek Deadman-6 6 0 5 0 11 0
Deadman-5 5 2 5 0 10 2
Deadman-4 5 1 5 0 5 23 15 24
Deadman-3 6 0 5 26 1 1 6 3 2 3 20 33
Deadman-1 1 1 1 0 1 29 3 30
Total1 3 0 3 13 112 116 59 338 2 6 10 0 47 143 72 141 143 251 220 116 671 1,124
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 53 October 2015
Table 5.1-11. Mean (±SD) percent bedrock substrate in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic Reach Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 0.0 0.0 6 0.0 0.0 7 0.0 0.0 18 0.0 0.0
Oshetna-2
Oshetna-1 5 0.0 0.0 4 0.0 0.0 2 0.0 0.0 11 0.0 0.0
Black River Black-3 5 0.0 0.0 2 0.0 0.0 5 0.0 0.0 5 0.0 0.0 17 0.0 0.0
Black-2 7 0.0 0.0 1 0.0 - 3 0.0 0.0 6 0.0 0.0 17 0.0 0.0
Black-1 4 0.0 0.0 1 0.0 - 5 0.0 0.0 5 0.0 0.0 15 0.0 0.0
Goose Creek Goose-3 5 0.0 0.0 1 0.0 - 6 0.0 0.0 12 0.0 0.0
Goose-2 5 0.0 0.0 3 0.0 0.0 5 0.0 0.0 13 0.0 0.0
Goose-1 7 0.0 0.0 1 0.0 - 4 0.0 0.0 5 0.0 0.0 17 0.0 0.0
Proposed reservoir full pool
Unnamed 230.2 NA 1 0.0 - 1 0.0 -
Unnamed 230.1 NA 3 0.0 0.0 3 0.0 0.0 1 0.0 - 7 0.0 0.0
Unnamed 228.5 NA 3 0.0 0.0 5 0.0 0.0 1 0.0 - 3 0.0 0.0 12 0.0 0.0
Unnamed 226.2 NA
Unnamed 219.6 NA 4 0.0 0.0 4 0.0 0.0
Unnamed 214.4 NA 1 0.0 - 1 0.0 -
Jay Creek Jay-4 1 0.0 - 5 0.0 0.0 5 0.0 0.0 6 0.0 0.0 17 0.0 0.0
Jay-3 5 0.0 0.0 3 0.0 0.0 2 0.0 0.0 7 0.0 0.0 17 0.0 0.0
Jay-2 5 0.0 0.0 6 0.0 0.0 4 0.0 0.0 5 0.0 0.0 20 0.0 0.0
Jay-1 3 0.0 0.0 1 0.0 - 1 0.0 - 2 0.0 0.0 1 0.0 - 11 0.0 0.0 15 0.0 0.0 34 0.0 0.0
Tsisi Creek Tsisi-2 5 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Tsisi-1 8 0.0 0.0 6 0.0 0.0 1 0.0 - 15 0.0 0.0
Kosina Creek Kosina-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0 26 0.0 0.0 34 0.0 0.0
Kosina-2 1 0.0 - 2 0.0 0.0 1 0.0 - 5 0.0 0.0 17 0.6 2.4 16 5.0 8.9 42 2.1 6.1
Kosina-1 2 0.0 0.0 14 0.0 0.0 13 0.0 0.0 29 0.0 0.0
Unnamed 208.6 NA 1 0.0 - 1 0.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 0.0 0.0 6 0.0 0.0
Unnamed 206.3 206.3-3 1 0.0 - 2 0.0 0.0 1 0.0 - 4 0.0 0.0
206.3-1 4 0.0 0.0 6 0.0 0.0 1 0.0 - 1 0.0 - 12 0.0 0.0
Unnamed 204.5 204.5-2 1 5.0 - 1 5.0 -
204.5-1 3 0.0 0.0 7 0.0 0.0 1 0.0 - 1 0.0 - 12 0.0 0.0
Unnamed 198.9 NA 1 0.0 - 1 0.0 -
Unnamed 198.4 LB-1 NA 1 0.0 - 1 0.0 -
Unnamed 197.7 197.7-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0
197.7-2 3 0.0 0.0 1 0.0 - 4 0.0 0.0
197.7-1 2 0.0 0.0 3 0.0 0.0 2 0.0 0.0 3 0.0 0.0 1 0.0 - 1 0.0 - 12 0.0 0.0
Unnamed 197.7 RB-1 NA 3 0.0 0.0 1 0.0 - 4 0.0 0.0
Watana Creek Trib Watana Trib-2 3 0.0 0.0 2 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Watana Trib-1 1 0.0 - 1 20.0 - 2 0.0 0.0 2 0.0 0.0 8 1.3 3.5 14 2.1 5.8
Watana Cr. LB-1.1.1 NA 1 0.0 - 2 0.0 0.0 2 0.0 0.0 5 0.0 0.0
Watana Cr. RB-1 NA 3 0.0 0.0 1 0.0 - 4 0.0 0.0 4 0.0 0.0 12 0.0 0.0
Watana Creek Watana-3 2 0.0 0.0 13 0.0 0.0 3 0.0 0.0 4 0.0 0.0 7 0.0 0.0 29 0.0 0.0
Watana-2 2 5.0 7.1 2 0.0 0.0 1 10.0 - 2 25.0 21.2 6 0.0 0.0 5 2.0 4.5 18 4.4 9.8
Watana-1 1 0.0 - 1 0.0 - 2 0.0 0.0 6 3.3 8.2 17 0.0 0.0 12 0.8 2.9 39 0.8 3.5
Unnamed 194.8 194.8-4 6 0.0 0.0 4 0.0 0.0 10 0.0 0.0
194.8-3 2 0.0 0.0 2 0.0 0.0 2 0.0 0.0 9 0.0 0.0 3 0.0 0.0 1 0.0 - 6 0.0 0.0 25 0.0 0.0
194.8-1 2 0.0 0.0 1 0.0 - 3 0.0 0.0
Deadman Creek Deadman-6 6 0.0 0.0 5 0.0 0.0 11 0.0 0.0
Deadman-5 5 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Deadman-4 5 0.0 0.0 5 0.0 0.0 4 0.0 0.0 14 0.0 0.0
Deadman-3 6 0.0 0.0 5 0.0 0.0 1 20.0 - 6 1.7 4.1 2 5.0 7.1 20 2.0 5.2
Deadman-1 1 10.0 - 1 20.0 - 1 0.0 - 3 10.0 10.0
Total1 3 0.0 0.0 3 0.0 0.0 112 0.1 0.9 59 0.3 1.4 2 10.0 14.1 10 0.0 0.0 48 1.5 5.0 64 0.9 5.3 139 0.1 0.8 208 0.6 3.1 648 0.5 3.0
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 54 October 2015
Table 5.1-12. Mean (±SD) percent boulder substrate in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 54.0 13.4 6 20.0 27.6 7 12.9 16.0 18 26.7 25.9
Oshetna-2
Oshetna-1 5 72.0 8.4 4 27.5 22.2 2 46.8 18.7 11 51.2 25.6
Black River Black-3 5 46.0 15.2 2 45.0 21.2 5 34.0 11.4 5 50.0 7.1 17 43.5 13.2
Black-2 7 58.6 10.7 1 50.0 - 3 30.0 20.0 6 26.7 12.1 17 41.8 19.4
Black-1 4 57.5 15.0 1 30.0 - 5 35.8 18.5 5 34.0 18.2 15 40.6 18.8
Goose Creek Goose-3 5 20.0 7.1 1 0.0 - 6 11.7 7.5 12 14.2 9.0
Goose-2 5 54.0 5.5 3 70.0 10.0 5 48.0 14.8 13 55.4 13.3
Goose-1 7 54.3 9.8 1 80.0 - 4 57.5 25.0 5 34.0 24.1 17 50.6 21.4
Proposed reservoir full pool
Unnamed 230.2 NA 1 35.0 - 1 35.0 -
Unnamed 230.1 NA 3 90.0 10.0 3 29.1 5.2 1 70.0 - 7 61.1 31.4
Unnamed 228.5 NA 3 31.7 15.3 5 22.0 5.7 1 5.0 - 3 6.7 2.9 12 19.2 12.8
Unnamed 226.2 NA
Unnamed 219.6 NA 4 27.2 24.2 4 27.2 24.2
Unnamed 214.4 NA 1 0.0 - 1 0.0 -
Jay Creek Jay-4 1 10.0 - 5 10.0 17.3 5 12.0 11.0 6 6.7 10.3 17 9.4 12.0
Jay-3 5 44.0 15.2 3 3.3 5.8 2 10.0 14.1 7 12.9 13.8 17 20.0 20.3
Jay-2 5 36.0 8.9 6 35.0 10.5 4 27.5 9.6 5 30.0 18.7 20 32.5 12.1
Jay-1 3 23.3 5.8 1 40.0 - 1 0.0 - 2 30.0 14.1 1 40.0 - 11 27.3 20.0 15 28.0 17.8 34 27.4 17.3
Tsisi Creek Tsisi-2 5 22.0 8.4 5 20.0 7.1 10 21.0 7.4
Tsisi-1 8 45.0 9.3 6 50.0 8.9 1 20.0 - 15 45.3 11.3
Kosina Creek Kosina-3 2 0.0 0.0 2 0.0 0.0 4 45.0 12.9 26 33.8 18.6 34 31.2 20.6
Kosina-2 1 50.0 - 2 25.0 21.2 1 70.0 - 5 72.0 11.0 17 48.2 13.3 16 50.0 10.3 42 51.2 15.2
Kosina-1 2 45.0 21.2 14 42.1 11.9 13 47.7 14.8 29 44.8 13.5
Unnamed 208.6 NA 1 10.0 - 1 10.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 22.5 24.0 6 22.5 24.0
Unnamed 206.3 206.3-3 1 80.0 - 2 5.0 7.1 1 10.0 - 4 25.0 37.0
206.3-1 4 22.5 5.0 6 28.3 7.5 1 20.0 - 1 20.0 - 12 25.0 6.7
Unnamed 204.5 204.5-2 1 65.0 - 1 65.0 -
204.5-1 3 26.7 5.8 7 58.6 29.5 1 0.0 - 1 0.0 - 12 40.8 32.3
Unnamed 198.9 NA 1 65.0 - 1 65.0 -
Unnamed 198.4 LB-1 NA 1 10.0 - 1 10.0 -
Unnamed 197.7 197.7-3 2 95.0 7.1 2 85.0 0.0 4 90.0 7.1
197.7-2 3 70.0 26.5 1 0.0 - 4 52.5 41.1
197.7-1 2 25.0 7.1 3 25.0 8.7 2 2.5 3.5 3 53.3 25.2 1 5.0 - 1 10.0 - 12 25.4 22.4
Unnamed 197.7 RB-1 NA 3 36.7 32.1 1 40.0 - 4 37.5 26.3
Watana Creek Trib Watana Trib-2 3 50.0 26.5 2 30.0 42.4 5 10.0 7.1 10 26.0 26.7
Watana Trib-1 1 0.0 - 1 30.0 - 2 40.0 14.1 2 35.0 7.1 8 16.3 11.9 14 22.1 15.3
Watana Cr. LB-1.1.1 NA 1 40.0 - 2 47.4 67.0 2 17.5 17.7 5 33.9 37.9
Watana Cr. RB-1 NA 3 0.0 0.0 1 0.0 - 4 0.0 0.0 4 0.0 0.0 12 0.0 0.0
Watana Creek Watana-3 2 10.0 0.0 13 45.4 9.7 3 50.0 0.0 4 25.0 5.8 7 17.1 16.0 29 33.8 17.6
Watana-2 2 50.0 0.0 2 5.0 7.1 1 10.0 - 2 45.0 7.1 6 11.7 13.3 5 20.0 7.1 18 21.1 17.5
Watana-1 1 0.0 - 1 50.0 - 2 0.0 0.0 6 6.7 8.2 17 7.1 9.2 12 15.0 11.7 39 10.0 12.1
Unnamed 194.8 194.8-4 6 8.3 7.5 4 20.0 11.5 10 13.0 10.6
194.8-3 2 5.0 7.1 2 75.0 7.1 2 70.0 14.1 9 18.9 20.9 3 46.7 35.1 1 0.0 - 6 16.7 16.3 25 28.4 28.8
194.8-1 2 15.0 0.0 1 5.0 - 3 11.7 5.8
Deadman Creek Deadman-6 6 25.0 23.5 5 8.0 8.4 11 17.3 19.5
Deadman-5 5 52.0 8.4 5 56.0 5.5 10 54.0 7.0
Deadman-4 5 44.0 5.5 5 54.0 15.2 4 16.1 12.5 14 39.6 19.3
Deadman-3 6 53.3 10.3 5 77.0 12.0 1 70.0 - 6 60.0 6.3 2 60.0 14.1 20 62.8 12.9
Deadman-1 1 90.0 - 1 40.0 - 1 85.0 - 3 71.7 27.5
Total1 3 10.0 0.0 3 3.3 5.8 112 46.2 16.4 59 49.4 31.2 2 40.0 42.4 10 6.0 12.6 48 16.4 18.5 64 49.6 19.0 139 26.0 21.1 208 27.0 20.5 648 33.1 23.9
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 55 October 2015
Table 5.1-13. Mean (±SD) percent cobble substrate in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 34.0 11.4 6 58.3 19.4 7 47.1 18.0 18 47.2 18.7
Oshetna-2
Oshetna-1 5 22.0 4.5 4 60.0 14.1 2 47.2 10.2 11 40.4 20.3
Black River Black-3 5 40.0 12.2 2 45.0 21.2 5 48.0 8.4 5 38.0 8.4 17 42.4 10.9
Black-2 7 34.3 12.7 1 40.0 - 3 56.7 15.3 6 50.0 16.7 17 44.1 16.2
Black-1 4 30.0 14.1 1 10.0 - 5 39.3 17.8 5 48.0 19.2 15 37.8 18.7
Goose Creek Goose-3 5 28.0 17.9 1 20.0 - 6 30.0 16.7 12 28.3 15.9
Goose-2 5 30.0 7.1 3 23.3 5.8 5 34.0 11.4 13 30.0 9.1
Goose-1 7 27.1 4.9 1 20.0 - 4 35.0 17.3 5 26.0 5.5 17 28.2 9.5
Proposed reservoir full pool
Unnamed 230.2 NA 1 45.0 - 1 45.0 -
Unnamed 230.1 NA 3 5.0 5.0 3 4.2 5.2 1 10.0 - 7 5.4 4.6
Unnamed 228.5 NA 3 45.0 8.7 5 58.0 16.0 1 50.0 - 3 65.0 18.0 12 55.8 15.1
Unnamed 226.2 NA
Unnamed 219.6 NA 4 36.5 5.0 4 36.5 5.0
Unnamed 214.4 NA 1 70.0 - 1 70.0 -
Jay Creek Jay-4 1 0.0 - 5 34.0 13.4 5 50.0 17.3 6 46.7 27.3 17 41.2 22.6
Jay-3 5 28.0 8.4 3 33.3 11.5 2 55.0 21.2 7 34.3 12.7 17 34.7 13.7
Jay-2 5 32.0 4.5 6 31.7 7.5 4 37.5 5.0 5 28.0 4.5 20 32.0 6.2
Jay-1 3 53.3 11.5 1 60.0 - 1 40.0 - 2 10.0 0.0 1 40.0 - 11 40.9 15.1 15 44.0 14.5 34 42.1 15.9
Tsisi Creek Tsisi-2 5 50.0 7.1 5 46.0 5.5 10 48.0 6.3
Tsisi-1 8 36.3 5.2 6 41.7 4.1 1 20.0 - 15 37.3 7.0
Kosina Creek Kosina-3 2 5.0 7.1 2 0.0 0.0 4 25.0 5.8 26 28.5 7.8 34 25.0 11.1
Kosina-2 1 30.0 - 2 20.0 0.0 1 30.0 - 5 22.0 4.5 17 30.6 4.3 16 27.5 10.0 42 27.9 7.5
Kosina-1 2 30.0 14.1 14 40.0 9.6 13 36.2 7.7 29 37.6 9.1
Unnamed 208.6 NA 1 60.0 - 1 60.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 17.5 5.2 6 17.5 5.2
Unnamed 206.3 206.3-3 1 10.0 - 2 15.0 21.2 1 80.0 - 4 30.0 35.6
206.3-1 4 45.0 5.8 6 30.0 12.6 1 30.0 - 1 50.0 - 12 36.7 12.3
Unnamed 204.5 204.5-2 1 0.0 - 1 0.0 -
204.5-1 3 20.0 10.0 7 20.7 19.0 1 0.0 - 1 5.0 - 12 17.5 16.3
Unnamed 198.9 NA 1 20.0 - 1 20.0 -
Unnamed 198.4 LB-1 NA 1 40.0 - 1 40.0 -
Unnamed 197.7 197.7-3 2 5.0 7.1 2 15.0 0.0 4 10.0 7.1
197.7-2 3 8.3 7.6 1 5.0 - 4 7.5 6.5
197.7-1 2 45.0 0.0 3 66.7 5.8 2 37.5 10.6 3 36.7 20.8 1 70.0 - 1 40.0 - 12 48.8 17.2
Unnamed 197.7 RB-1 NA 3 21.7 2.9 1 45.0 - 4 27.5 11.9
Watana Creek Trib Watana Trib-2 3 33.3 15.3 2 30.0 28.3 5 26.0 16.7 10 29.0 16.6
Watana Trib-1 1 10.0 - 1 30.0 - 2 40.0 14.1 2 40.0 0.0 8 43.8 10.6 14 39.3 12.7
Watana Cr. LB-1.1.1 NA 1 0.0 - 2 5.0 7.1 2 17.5 24.7 5 9.0 15.2
Watana Cr. RB-1 NA 3 0.0 0.0 1 0.0 - 4 2.8 3.3 4 2.5 2.9 12 1.8 2.6
Watana Creek Watana-3 2 15.0 21.2 13 26.9 6.0 3 30.0 0.0 4 42.5 5.0 7 32.9 22.1 29 30.0 13.6
Watana-2 2 25.0 7.1 2 20.0 0.0 1 30.0 - 2 25.0 7.1 6 36.7 15.1 5 38.0 4.5 18 32.2 11.1
Watana-1 1 0.0 - 1 30.0 - 2 0.0 0.0 6 28.3 22.3 17 52.4 20.8 12 48.3 19.9 39 42.8 24.4
Unnamed 194.8 194.8-4 6 6.7 12.1 4 5.0 5.8 10 6.0 9.7
194.8-3 2 0.0 0.0 2 5.0 7.1 2 15.0 7.1 9 7.8 9.7 3 30.0 10.0 1 0.0 - 6 26.7 23.4 25 14.4 16.6
194.8-1 2 45.0 21.2 1 30.0 - 3 40.0 17.3
Deadman Creek Deadman-6 6 33.3 17.5 5 8.0 8.4 11 21.8 18.9
Deadman-5 5 36.0 5.5 5 36.0 5.5 10 36.0 5.2
Deadman-4 5 36.0 8.9 5 36.0 8.9 4 28.9 13.2 14 34.0 10.0
Deadman-3 6 26.7 10.3 5 13.0 7.6 1 5.0 - 6 29.2 8.0 2 10.0 14.1 20 21.3 11.9
Deadman-1 1 0.0 - 1 10.0 - 1 10.0 - 3 6.7 5.8
Total1 3 10.0 17.3 3 0.0 0.0 112 31.7 11.5 59 23.1 19.8 2 22.5 24.7 10 14.0 12.6 48 17.9 16.9 64 34.8 13.7 139 39.7 18.5 208 34.3 17.9 648 32.2 18.1
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 56 October 2015
Table 5.1-14. Mean (±SD) percent gravel substrate in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 12.0 4.5 6 21.7 11.7 7 38.6 23.4 18 25.6 19.2
Oshetna-2
Oshetna-1 5 6.0 5.5 4 12.5 12.6 2 6.0 8.5 11 8.4 8.8
Black River Black-3 5 10.0 7.1 2 10.0 0.0 5 16.0 8.9 5 8.0 4.5 17 11.2 7.0
Black-2 7 7.1 4.9 1 10.0 - 3 10.0 0.0 6 13.3 8.2 17 10.0 6.1
Black-1 4 10.0 0.0 1 50.0 - 5 17.0 18.6 5 16.0 19.5 15 17.0 17.3
Goose Creek Goose-3 5 34.0 16.7 1 70.0 - 6 33.3 22.5 12 36.7 21.0
Goose-2 5 12.0 4.5 3 6.7 5.8 5 10.0 7.1 13 10.0 5.8
Goose-1 7 15.7 9.8 1 0.0 - 4 7.5 9.6 5 36.0 27.0 17 18.8 19.6
Proposed reservoir full pool
Unnamed 230.2 NA 1 15.0 - 1 15.0 -
Unnamed 230.1 NA 3 5.0 5.0 3 51.6 17.5 1 20.0 - 7 27.1 25.8
Unnamed 228.5 NA 3 21.7 15.3 5 20.0 14.1 1 45.0 - 3 28.3 15.3 12 24.6 14.5
Unnamed 226.2 NA
Unnamed 219.6 NA 4 20.5 8.9 4 20.5 8.9
Unnamed 214.4 NA 1 30.0 - 1 30.0 -
Jay Creek Jay-4 1 0.0 - 5 40.0 15.8 5 36.0 16.7 6 43.3 30.8 17 37.6 23.1
Jay-3 5 22.0 8.4 3 33.3 11.5 2 35.0 7.1 7 35.7 16.2 17 31.2 13.2
Jay-2 5 18.0 8.4 6 23.3 5.2 4 27.5 5.0 5 38.0 11.0 20 26.5 10.4
Jay-1 3 16.7 11.5 1 0.0 - 1 0.0 - 2 0.0 0.0 1 20.0 - 11 28.2 14.7 15 23.3 11.1 34 21.5 14.2
Tsisi Creek Tsisi-2 5 22.0 8.4 5 20.0 0.0 10 21.0 5.7
Tsisi-1 8 15.0 9.3 6 8.3 9.8 1 20.0 - 15 12.7 9.6
Kosina Creek Kosina-3 2 25.0 21.2 2 50.0 0.0 4 17.5 9.6 26 21.2 11.4 34 22.6 13.1
Kosina-2 1 20.0 - 2 30.0 14.1 1 0.0 - 5 6.0 8.9 17 17.1 8.5 16 12.5 10.0 42 14.3 10.4
Kosina-1 2 20.0 0.0 14 17.9 8.0 13 16.2 9.6 29 17.2 8.4
Unnamed 208.6 NA 1 30.0 - 1 30.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 40.0 18.2 6 40.0 18.2
Unnamed 206.3 206.3-3 1 10.0 - 2 50.0 0.0 1 10.0 - 4 30.0 23.1
206.3-1 4 20.0 0.0 6 21.7 7.5 1 30.0 - 1 20.0 - 12 21.7 5.8
Unnamed 204.5 204.5-2 1 15.0 - 1 15.0 -
204.5-1 3 31.7 7.6 7 12.9 8.1 1 65.0 - 1 15.0 - 12 22.1 17.2
Unnamed 198.9 NA 1 15.0 - 1 15.0 -
Unnamed 198.4 LB-1 NA 1 30.0 - 1 30.0 -
Unnamed 197.7 197.7-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0
197.7-2 3 21.7 24.7 1 90.0 - 4 38.8 39.7
197.7-1 2 25.0 7.1 3 8.3 7.6 2 35.0 7.1 3 8.3 10.4 1 25.0 - 1 40.0 - 12 19.6 14.1
Unnamed 197.7 RB-1 NA 3 35.0 31.2 1 10.0 - 4 28.8 28.4
Watana Creek Trib Watana Trib-2 3 16.7 11.5 2 25.0 7.1 5 52.0 13.0 10 36.0 20.1
Watana Trib-1 1 0.0 - 1 20.0 - 2 20.0 0.0 2 25.0 7.1 8 30.0 14.1 14 25.0 13.4
Watana Cr. LB-1.1.1 NA 1 0.0 - 2 20.0 28.3 2 0.0 0.0 5 8.0 17.9
Watana Cr. RB-1 NA 3 5.0 5.0 1 20.0 - 4 28.1 35.6 4 27.5 36.6 12 21.5 28.6
Watana Creek Watana-3 2 5.0 7.1 13 27.7 7.0 3 20.0 0.0 4 32.5 5.0 7 47.1 25.6 29 30.7 17.3
Watana-2 2 20.0 0.0 2 30.0 14.1 1 40.0 - 2 5.0 7.1 6 41.7 16.0 5 34.0 11.4 18 31.7 16.2
Watana-1 1 0.0 - 1 20.0 - 2 20.0 28.3 6 40.0 17.9 17 34.7 15.9 12 29.2 19.3 39 31.8 18.2
Unnamed 194.8 194.8-4 6 20.0 11.0 4 40.0 14.1 10 28.0 15.5
194.8-3 2 35.0 7.1 2 5.0 7.1 2 10.0 14.1 9 22.2 22.8 3 16.7 15.3 1 90.0 - 6 33.3 24.2 25 25.6 24.3
194.8-1 2 40.0 21.2 1 60.0 - 3 46.7 18.9
Deadman Creek Deadman-6 6 30.0 17.9 5 24.0 33.6 11 27.3 24.9
Deadman-5 5 10.0 0.0 5 8.0 4.5 10 9.0 3.2
Deadman-4 5 14.0 13.4 5 4.0 5.5 4 26.1 7.3 14 13.9 12.7
Deadman-3 6 8.3 4.1 5 7.0 2.7 1 0.0 - 6 5.8 4.9 2 5.0 7.1 20 6.5 4.3
Deadman-1 1 0.0 - 1 30.0 - 1 5.0 - 3 11.7 16.1
Total1 3 3.3 5.8 3 23.3 20.8 112 16.9 11.3 59 16.3 16.0 2 15.0 21.2 10 21.0 17.9 48 30.1 19.7 64 12.0 9.9 139 26.7 17.6 208 25.3 19.2 648 22.2 17.5
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 57 October 2015
Table 5.1-15. Mean (±SD) percent and and silt substrate in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 0.0 0.0 6 0.0 0.0 7 1.4 3.8 18 0.6 2.4
Oshetna-2
Oshetna-1 5 0.0 0.0 4 0.0 0.0 2 0.0 0.0 11 0.0 0.0
Black River Black-3 5 0.0 0.0 2 0.0 0.0 5 0.0 0.0 5 0.0 0.0 17 0.0 0.0
Black-2 7 0.0 0.0 1 0.0 - 3 3.3 5.8 6 8.3 11.7 17 3.5 7.9
Black-1 4 0.0 0.0 1 10.0 - 5 4.0 5.5 5 0.0 0.0 15 2.0 4.1
Goose Creek Goose-3 5 12.0 8.4 1 10.0 - 6 21.7 7.5 12 16.7 8.9
Goose-2 5 4.0 5.5 3 0.0 0.0 5 4.0 5.5 13 3.1 4.8
Goose-1 7 2.9 4.9 1 0.0 - 4 0.0 0.0 5 4.0 5.5 17 2.4 4.4
Proposed reservoir full pool
Unnamed 230.2 NA 1 5.0 - 1 5.0 -
Unnamed 230.1 NA 3 0.0 0.0 3 15.0 15.0 1 0.0 - 7 6.4 11.8
Unnamed 228.5 NA 3 1.7 2.9 5 0.0 0.0 1 0.0 - 3 0.0 0.0 12 0.4 1.4
Unnamed 226.2 NA
Unnamed 219.6 NA 4 15.9 16.6 4 15.9 16.6
Unnamed 214.4 NA 1 0.0 - 1 0.0 -
Jay Creek Jay-4 1 90.0 - 5 14.0 16.7 5 2.0 4.5 6 3.3 5.2 17 11.2 22.9
Jay-3 5 4.0 5.5 3 20.0 10.0 2 0.0 0.0 7 11.4 13.5 17 9.4 11.4
Jay-2 5 14.0 5.5 6 8.3 4.1 4 7.5 5.0 5 4.0 5.5 20 8.5 5.9
Jay-1 3 6.7 5.8 1 0.0 - 1 60.0 - 2 60.0 14.1 1 0.0 - 11 3.6 6.7 15 4.7 6.4 34 9.1 17.3
Tsisi Creek Tsisi-2 5 2.0 4.5 5 6.0 5.5 10 4.0 5.2
Tsisi-1 8 1.3 3.5 6 0.0 0.0 1 30.0 - 15 2.7 8.0
Kosina Creek Kosina-3 2 45.0 35.4 2 50.0 0.0 4 12.5 5.0 26 16.5 12.6 34 19.7 16.4
Kosina-2 1 0.0 - 2 20.0 14.1 1 0.0 - 5 0.0 0.0 17 3.5 7.9 16 5.0 8.2 42 4.3 8.3
Kosina-1 2 5.0 7.1 14 0.0 0.0 13 0.0 0.0 29 0.3 1.9
Unnamed 208.6 NA 1 0.0 - 1 0.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 20.0 13.8 6 20.0 13.8
Unnamed 206.3 206.3-3 1 0.0 - 2 30.0 14.1 1 0.0 - 4 15.0 19.1
206.3-1 4 10.0 0.0 6 18.3 11.7 1 20.0 - 1 10.0 - 12 15.0 9.0
Unnamed 204.5 204.5-2 1 15.0 - 1 15.0 -
204.5-1 3 21.7 7.6 7 7.9 7.0 1 25.0 - 1 80.0 - 12 18.8 21.4
Unnamed 198.9 NA 1 0.0 - 1 0.0 -
Unnamed 198.4 LB-1 NA 1 10.0 - 1 10.0 -
Unnamed 197.7 197.7-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0
197.7-2 3 0.0 0.0 1 5.0 - 4 1.3 2.5
197.7-1 2 5.0 0.0 3 0.0 0.0 2 25.0 7.1 3 1.7 2.9 1 0.0 - 1 10.0 - 12 6.3 9.6
Unnamed 197.7 RB-1 NA 3 6.7 2.9 1 5.0 - 4 6.3 2.5
Watana Creek Trib Watana Trib-2 3 0.0 0.0 2 15.0 7.1 5 12.0 4.5 10 9.0 7.4
Watana Trib-1 1 90.0 - 1 0.0 - 2 0.0 0.0 2 0.0 0.0 8 8.8 6.4 14 11.4 23.5
Watana Cr. LB-1.1.1 NA 1 60.0 - 2 15.1 14.0 2 52.5 53.0 5 39.1 35.2
Watana Cr. RB-1 NA 3 40.0 13.2 1 80.0 - 4 44.1 27.9 4 52.5 33.0 12 48.9 25.8
Watana Creek Watana-3 2 70.0 28.3 13 0.0 0.0 3 0.0 0.0 4 0.0 0.0 7 2.9 4.9 29 5.5 18.8
Watana-2 2 0.0 0.0 2 30.0 14.1 1 10.0 - 2 0.0 0.0 6 10.0 12.6 5 6.0 5.5 18 8.9 11.8
Watana-1 1 50.0 - 1 0.0 - 2 55.0 7.1 6 21.7 9.8 17 5.9 11.8 12 6.7 7.8 39 12.1 16.4
Unnamed 194.8 194.8-4 6 35.0 17.6 4 22.5 5.0 10 30.0 14.9
194.8-3 2 35.0 7.1 2 15.0 7.1 2 5.0 7.1 9 35.6 8.8 3 6.7 11.5 1 10.0 - 6 23.3 10.3 25 24.0 14.4
194.8-1 2 0.0 0.0 1 5.0 - 3 1.7 2.9
Deadman Creek Deadman-6 6 11.7 4.1 5 60.0 33.9 11 33.6 33.2
Deadman-5 5 2.0 4.5 5 0.0 0.0 10 1.0 3.2
Deadman-4 5 6.0 5.5 5 6.0 5.5 4 28.9 30.0 14 12.5 18.5
Deadman-3 6 11.7 7.5 5 3.0 4.5 1 5.0 - 6 3.3 5.2 2 20.0 0.0 20 7.5 7.7
Deadman-1 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Total1 3 76.7 23.1 3 40.0 10.0 112 4.2 6.7 59 8.1 12.3 2 7.5 3.5 10 45.0 25.5 48 26.7 20.0 64 2.5 5.0 139 6.2 11.7 208 11.3 17.5 648 9.9 16.4
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 58 October 2015
Table 5.1-16. Mean (±SD) percent organic substrate in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 5 0.0 0.0 6 0.0 0.0 7 0.0 0.0 18 0.0 0.0
Oshetna-2
Oshetna-1 5 0.0 0.0 4 0.0 0.0 2 0.0 0.0 11 0.0 0.0
Black River Black-3 5 4.0 5.5 2 0.0 0.0 5 2.0 4.5 5 4.0 5.5 17 2.9 4.7
Black-2 7 0.0 0.0 1 0.0 - 3 0.0 0.0 6 1.7 4.1 17 0.6 2.4
Black-1 4 2.5 5.0 1 0.0 - 5 4.0 5.5 5 2.0 4.5 15 2.7 4.6
Goose Creek Goose-3 5 6.0 5.5 1 0.0 - 6 3.3 5.2 12 4.2 5.1
Goose-2 5 0.0 0.0 3 0.0 0.0 5 4.0 5.5 13 1.5 3.8
Goose-1 7 0.0 0.0 1 0.0 - 4 0.0 0.0 5 0.0 0.0 17 0.0 0.0
Proposed reservoir full pool
Unnamed 230.2 NA 1 0.0 - 1 0.0 -
Unnamed 230.1 NA 3 0.0 0.0 3 0.0 0.0 1 0.0 - 7 0.0 0.0
Unnamed 228.5 NA 3 0.0 0.0 5 0.0 0.0 1 0.0 - 3 0.0 0.0 12 0.0 0.0
Unnamed 226.2 NA
Unnamed 219.6 NA 4 0.0 0.0 4 0.0 0.0
Unnamed 214.4 NA 1 0.0 - 1 0.0 -
Jay Creek Jay-4 1 0.0 - 5 2.0 4.5 5 0.0 0.0 6 0.0 0.0 17 0.6 2.4
Jay-3 5 2.0 4.5 3 10.0 17.3 2 0.0 0.0 7 5.7 15.1 17 4.7 11.8
Jay-2 5 0.0 0.0 6 1.7 4.1 4 0.0 0.0 5 0.0 0.0 20 0.5 2.2
Jay-1 3 0.0 0.0 1 0.0 - 1 0.0 - 2 0.0 0.0 1 0.0 - 11 0.0 0.0 15 0.0 0.0 34 0.0 0.0
Tsisi Creek Tsisi-2 5 4.0 5.5 5 8.0 4.5 10 6.0 5.2
Tsisi-1 8 2.5 4.6 6 0.0 0.0 1 10.0 - 15 2.0 4.1
Kosina Creek Kosina-3 2 25.0 21.2 2 0.0 0.0 4 0.0 0.0 26 0.0 0.0 34 1.5 7.0
Kosina-2 1 0.0 - 2 5.0 7.1 1 0.0 - 5 0.0 0.0 17 0.0 0.0 16 0.0 0.0 42 0.2 1.5
Kosina-1 2 0.0 0.0 14 0.0 0.0 13 0.0 0.0 29 0.0 0.0
Unnamed 208.6 NA 1 0.0 - 1 0.0 -
Unnamed 207.4 RB-1 207.4 RB-1
Unnamed 207.4 NA 6 0.0 0.0 6 0.0 0.0
Unnamed 206.3 206.3-3 1 0.0 - 2 0.0 0.0 1 0.0 - 4 0.0 0.0
206.3-1 4 2.5 5.0 6 1.7 4.1 1 0.0 - 1 0.0 - 12 1.7 3.9
Unnamed 204.5 204.5-2 1 0.0 - 1 0.0 -
204.5-1 3 0.0 0.0 7 0.0 0.0 1 10.0 - 1 0.0 - 12 0.8 2.9
Unnamed 198.9 NA 1 0.0 - 1 0.0 -
Unnamed 198.4 LB-1 NA 1 10.0 - 1 10.0 -
Unnamed 197.7 197.7-3 2 0.0 0.0 2 0.0 0.0 4 0.0 0.0
197.7-2 3 0.0 0.0 1 0.0 - 4 0.0 0.0
197.7-1 2 0.0 0.0 3 0.0 0.0 2 0.0 0.0 3 0.0 0.0 1 0.0 - 1 0.0 - 12 0.0 0.0
Unnamed 197.7 RB-1 NA 3 0.0 0.0 1 0.0 - 4 0.0 0.0
Watana Creek Trib Watana Trib-2 3 0.0 0.0 2 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Watana Trib-1 1 0.0 - 1 0.0 - 2 0.0 0.0 2 0.0 0.0 8 0.0 0.0 14 0.0 0.0
Watana Cr. LB-1.1.1 NA 1 0.0 - 2 12.5 17.7 2 12.5 10.6 5 10.0 11.7
Watana Cr. RB-1 NA 3 55.0 13.2 1 0.0 - 4 25.0 20.8 4 17.5 35.0 12 27.9 28.2
Watana Creek Watana-3 2 0.0 0.0 13 0.0 0.0 3 0.0 0.0 4 0.0 0.0 7 0.0 0.0 29 0.0 0.0
Watana-2 2 0.0 0.0 2 15.0 21.2 1 0.0 - 2 0.0 0.0 6 0.0 0.0 5 0.0 0.0 18 1.7 7.1
Watana-1 1 50.0 - 1 0.0 - 2 25.0 35.4 6 0.0 0.0 17 0.0 0.0 12 0.0 0.0 39 2.6 11.2
Unnamed 194.8 194.8-4 6 30.0 30.3 4 12.5 5.0 10 23.0 24.5
194.8-3 2 25.0 7.1 2 0.0 0.0 2 0.0 0.0 9 15.6 14.2 3 0.0 0.0 1 0.0 - 6 0.0 0.0 25 7.6 12.3
194.8-1 2 0.0 0.0 1 0.0 - 3 0.0 0.0
Deadman Creek Deadman-6 6 0.0 0.0 5 0.0 0.0 11 0.0 0.0
Deadman-5 5 0.0 0.0 5 0.0 0.0 10 0.0 0.0
Deadman-4 5 0.0 0.0 5 0.0 0.0 4 0.0 0.0 14 0.0 0.0
Deadman-3 6 0.0 0.0 5 0.0 0.0 1 0.0 - 6 0.0 0.0 2 0.0 0.0 20 0.0 0.0
Deadman-1 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Total1 3 0.0 0.0 3 33.3 15.3 112 0.9 2.9 59 3.0 12.5 2 5.0 7.1 10 14.0 19.0 48 7.5 16.0 64 0.2 1.3 139 1.3 5.9 208 1.5 6.4 648 2.2 8.4
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 59 October 2015
Table 5.1-17. Mean (±SD) percent instream cover in mesohabitat units of Upper River tributaries.
Tributary Name Geomorphic
Reach
Aquatic Vegetation Boulder Cobble Depth Insufficient Cover Overhanging
Vegetation Undercut Bank Woody Debris All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Oshetna River Oshetna-3 4 45.0 23.8 3 33.3 20.8 3 33.3 25.2 7 0.0 0.0 1 10.0 - 1 10.0 - 19 21.1 24.0
Oshetna-2 6 0.0 0.0 6 0.0 0.0
Oshetna-1 4 57.5 12.6 1 0.0 - 6 0.0 0.0 11 20.9 29.8
Black River Black-3 10 16.0 7.0 7 0.0 0.0 17 9.4 9.7
Black-2 15 32.0 9.4 1 0.0 - 1 10.0 - 17 28.8 12.7
Black-1 7 16.4 7.5 2 40.0 28.3 6 0.0 0.0 15 13.0 16.2
Goose Creek Goose-3 5 24.0 11.4 6 10.0 0.0 1 10.0 - 12 15.8 10.0
Goose-2 13 44.6 12.7 13 44.6 12.7
Goose-1 14 32.1 12.5 1 10.0 - 1 0.0 - 2 15.0 7.1 18 27.2 14.9
Unnamed 230.2 NA 1 0.0 - 1 0.0 -
Unnamed 230.1 NA 4 72.8 24.2 2 0.0 0.0 1 100.0 - 7 55.9 43.0
Unnamed 228.5 NA 8 52.5 13.6 1 70.0 - 3 46.7 37.9 12 52.5 20.4
Unnamed 226.2 NA 2 15.0 7.1 1 20.0 - 1 0.0 - 4 12.5 9.6
Unnamed 219.6 NA 1 50.0 - 1 50.0 -
Unnamed 214.4 Jay-4 5 32.0 4.5 9 0.0 0.0 3 13.3 5.8 17 11.8 14.7
Jay Creek Jay-3 5 42.0 13.0 1 0.0 - 1 10.0 - 7 31.4 21.2
Jay-2 9 31.1 7.8 2 0.0 0.0 1 10.0 - 2 20.0 0.0 14 23.6 13.4
Jay-1 5 16.0 5.5 4 0.0 0.0 9 8.9 9.3
Tsisi-2 9 17.8 8.3 1 10.0 - 10 17.0 8.2
Tsisi Creek Tsisi-1 14 49.3 8.3 1 10.0 - 15 46.7 12.9
Kosina-3 7 23.6 14.9 5 0.0 0.0 8 11.9 5.3 1 10.0 - 21 12.9 12.6
Kosina Creek Kosina-2 14 38.9 20.0 2 22.5 24.7 16 36.9 20.5
NA 1 0.0 - 1 0.0 -
NA 2 10.0 0.0 1 10.0 - 3 0.0 0.0 6 5.0 5.5
Unnamed 208.6 206.3-3 3 30.0 10.0 1 20.0 - 4 27.5 9.6
Unnamed 207.4 RB-1 206.3-1 7 21.4 6.9 2 0.0 0.0 3 26.7 5.8 12 19.2 10.8
Unnamed 207.4 204.5-2 1 20.0 - 1 20.0 -
Unnamed 206.3 204.5-1 9 23.9 11.9 3 0.0 0.0 12 17.9 14.8
NA 1 45.0 - 1 45.0 -
Unnamed 204.5 NA 1 70.0 - 1 70.0 -
197.7-3 4 100.0 0.0 4 100.0 0.0
Unnamed 198.9 197.7-2 3 26.7 5.8 1 10.0 - 4 22.5 9.6
Unnamed 198.4 LB-1 197.7-1 3 18.3 2.9 1 20.0 - 3 46.7 23.1 3 25.0 13.2 1 30.0 - 11 29.1 16.9
Unnamed 197.7 NA 3 31.7 2.9 1 0.0 - 4 23.8 16.0
Watana Trib-2 10 84.0 16.5 10 84.0 16.5
Watana Trib-1 3 10.0 0.0 1 40.0 - 2 15.0 7.1 7 25.7 16.2 1 30.0 - 14 22.1 14.2
Unnamed 197.7 RB-1 NA 1 10.0 - 3 48.3 27.5 1 60.0 - 5 43.0 27.3
Watana Creek Trib NA 4 0.0 0.0 6 7.5 6.1 2 15.0 7.1 12 6.3 7.1
Watana-3 14 15.0 6.5 4 0.0 0.0 11 24.5 28.1 29 16.6 19.1
Watana Cr. LB-1.1.1 Watana-2 7 12.9 4.9 1 30.0 - 4 0.0 0.0 4 48.8 39.2 1 20.0 - 17 19.7 25.2
Watana Cr. RB-1 Watana-1 1 40.0 - 3 13.3 5.8 8 0.0 0.0 1 5.0 - 13 6.5 11.8
Watana Creek 194.8-4 5 20.0 12.2 3 0.0 0.0 2 25.0 21.2 10 15.0 15.1
194.8-3 4 42.5 20.6 1 0.0 - 8 20.0 10.7 11 18.2 7.5 1 20.0 - 25 22.0 14.4
194.8-1 2 20.0 0.0 1 30.0 - 3 23.3 5.8
Unnamed 194.8 Deadman-6 3 33.3 23.1 2 25.0 7.1 1 70.0 - 4 0.0 0.0 10 22.0 25.3
Deadman-5 10 42.0 7.9 10 42.0 7.9
Deadman-4 12 36.7 16.1 1 34.5 - 1 30.0 - 14 36.0 15.0
Deadman Creek Deadman-3 18 38.3 14.3 1 80.0 - 19 40.5 16.9
Deadman-1 2 80.0 0.0 1 70.0 - 3 76.7 5.8
Total1 2 25.0 21.2 264 32.2 18.0 13 30.3 19.6 21 38.1 21.8 97 0.0 0.0 87 32.4 32.3 19 19.5 9.1 14 25.7 19.9 517 25.7 23.3
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 60 October 2015
Table 5.1-18. Sum of length (m) surveyed and composition by length of riparian cover types along Upper River tributaries.
Tributary Name Geomorphic
Reach
Broadleaf Forest Closed Broadleaf Forest Open Conifer Forest Closed Conifer Forest Open None Nonforest Herbaceous
Other Nonforest Shrub Alder Nonforest Shrub Other Nonforest Shrub Willow All Units2
n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length
Oshetna River Oshetna-3 1 93 2% 16 2,182 56% 1 258 7% 7 1,032 27% 4 314 8% 29 3,879
Oshetna-2 6 1,078 100% 6 1,078
Oshetna-1 9 1,960 51% 2 999 26% 4 714 18% 2 195 5% 17 3,868
Black River Black-3 3 174 13% 14 1,194 87% 17 1,368
Black-2 7 359 33% 10 744 67% 17 1,103
Black-1 5 757 36% 1 31 1% 9 1,301 62% 15 2,089
Goose Creek Goose-3 1 51 8% 11 558 92% 12 609
Goose-2 4 427 37% 4 405 35% 5 327 28% 13 1,158
Goose-1 5 163 12% 4 344 24% 2 218 16% 7 682 48% 18 1,407
Proposed reservoir full pool
Unnamed 230.2 NA 1 54 100% 1 54
Unnamed 230.1 NA 7 154 100% 7 154
Unnamed 228.5 NA 1 59 12% 3 84 17% 8 343 71% 12 485
Unnamed 226.2 NA 1 50 100% 1 50
Unnamed 219.6 NA 4 193 100% 4 193
Unnamed 214.4 NA 1 224 100% 1 224
Jay Creek Jay-4 5 192 38% 12 312 62% 17 503
Jay-3 1 21 2% 1 40 4% 1 56 5% 14 948 89% 17 1,065
Jay-2 2 162 9% 1 50 3% 4 498 29% 13 1,022 59% 20 1,732
Jay-1 3 19 2% 1 21 2% 2 43 4% 28 994 92% 34 1,077
Tsisi Creek Tsisi-2 10 617 100% 10 617
Tsisi-1 2 181 18% 13 835 82% 15 1,016
Kosina Creek Kosina-3 5 - - 1 - - 2 135 6% 26 2,169 94% 34 2,304
Kosina-2 1 262 6% 2 47 1% 8 514 13% 31 3,268 80% 42 4,091
Kosina-1 10 433 30% 4 106 7% 7 537 37% 8 385 26% 29 1,461
Unnamed 208.6 NA 1 61 100% 1 61
Unnamed 207.4 NA 6 128 100% 6 128
Unnamed 206.3 206.3-3 4 20 100% 4 20
206.3-1 1 22 9% 1 40 16% 10 184 75% 12 246
Unnamed 204.5 204.5-2 1 146 100% 1 146
204.5-1 12 423 100% 12 423
Unnamed 198.9 NA 1 63 100% 1 63
Unnamed 198.4 LB-1 NA 1 46 100% 1 46
Unnamed 197.7 197.7-3 4 76 100% 4 76
197.7-2 4 134 100% 4 134
197.7-1 8 337 76% 3 102 23% 1 5 1% 12 443
Unnamed 197.7 RB-1 NA 2 276 90% 2 31 10% 4 307
Watana Creek Trib Watana Trib-2 10 142 100% 10 142
Watana Trib-1 3 96 17% 11 453 83% 14 549
Watana Cr. LB-1.1.1 NA 5 345 100% 5 345
Watana Creek RB-1 NA 2 28 18% 6 48 31% 4 81 52% 12 157
Watana Creek Watana-3 1 26 3% 27 932 97% 28 958
Watana-2 4 102 8% 14 1,117 92% 18 1,219
Watana-1 1 11 0.40% 2 234 9% 1 47 2% 4 306 11% 4 316 12% 8 426 16% 18 1,396 51% 38 2,737
Unnamed 194.8 194.8-4 3 62 39% 6 91 57% 1 6 4% 10 159
194.8-3 16 483 72% 9 185 28% 25 667
194.8-1 3 382 100% 3 382
Deadman Creek Deadman-6 10 1,892 94% 1 130 6% 11 2,022
Deadman-5 10 1,190 100% 10 1,190
Deadman-4 4 999 36% 2 183 7% 8 1,568 57% 14 2,750
Deadman-3 9 1,347 57% 11 1,021 43% 20 2,368
Deadman-1 3 504 100% 3 504
Total1 5 332 1% 20 1,257 3% 7 361 1% 29 1,404 3% 14 646 1% 111 10,953 22% 107 7,190 14% 25 3,421 7% 353 24,262 49% 671 49,825
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 61 October 2015
Table 5.1-19. Sample sizes and mean and standard deviation (sd) of mesohabitat length measurements in meters made among geomorphic reaches by macrohabitat in mainstem habitats surveyed.
Geo-
morphic
Reach
Focus
Area Macrohabitat
Backwater Beaver Complex Boulder Riffle Cascade Clearwater Plume Dry Unspecified Pool Puddled Rapid Riffle Run/Glide All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean n Mean SD n Mean SD
UR-3 NA Main Channel 5 775 184 4 488 346 9 647 291
NA Side Slough 1 41 - 1 6 - 1 11 - 3 19 19
NA Tributary Mouth 1 2 - 1 25 - 3 29 22 5 23 20
UR-4 NA Main Channel 3 988 688 2 577 386 5 824 570
NA Split Main Channel 2 827 24 3 583 229 5 680 211
NA Side Channel 2 571 55 2 571 55
NA Side Slough 4 86 86 2 100 57 3 54 21 6 51 25 8 212 254 23 118 164
NA Upland Slough 5 49 46 10 115 95 2 105 30 5 60 29 11 67 64 33 80 70
NA Tributary Mouth 1 43 - 1 5 - 1 34 - 4 19 21 1 7 - 8 21 19
UR-5 NA Split Main Channel 1 287 - 1 287 -
NA Side Channel 1 38 - 1 157 - 1 272 - 3 156 117
NA Tributary Mouth 1 6 - 1 12 - 2 9 4
UR-6 NA Main Channel 2 3,611 4,366 2 3,611 4,366
NA Multi-Split Main Channel 1 91 - 4 662 559 5 548 547
NA Split Main Channel 2 1,053 60 2 1,053 60
NA Side Channel 1 64 - 1 169 - 2 116 74
NA Side Slough 1 83 - 1 32 - 2 119 147 1 38 - 4 48 31 9 64 65
NA Upland Slough 1 115 - 1 5 - 3 39 30 5 48 46
NA Tributary Mouth 1 21 - 1 21 -
MR-2 NA Main Channel 2 461 429 1 363 - 1 765 - 4 512 303
NA Side Slough 1 88 - 1 88 -
NA Upland Slough 2 117 138 1 57 - 3 97 103
NA Tributary Mouth 1 30 - 2 25 6 3 26 5
MR-3 NA Main Channel 1 410 - 1 3,676 - 2 2,043 2,309
NA Split Main Channel 1 574 - 1 574 -
NA Side Channel 1 20 - 1 485 - 2 252 329
NA Tributary Mouth 1 25 - 1 9 - 2 17 11
MR-5 NA Split Main Channel 1 966 - 1 966 -
MR-6 NA Main Channel 3 144 110 1 322 - 2 791 456 6 389 384
NA Multi-Split Main Channel 1 259 - 1 125 - 2 71 44 3 395 335 7 244 248
NA Split Main Channel 1 156 - 1 136 - 2 300 - 4 223 89
NA Side Channel 1 42 - 1 80 - 1 122 - 1 216 - 4 115 75
NA Side Slough 1 41 - 6 159 113 4 37 30 2 39 3 3 16 19 4 63 19 20 76 83
NA Upland Slough 4 152 57 6 321 271 2 223 290 2 215 218 1 64 - 2 33 25 4 100 62 21 188 191
NA Tributary Mouth 2 29 33 1 74 - 3 44 35
MR-7 NA Main Channel 1 25 - 1 495 - 5 562 366 7 476 360
NA Split Main Channel 1 198 - 2 348 55 1 502 - 4 349 128
NA Side Channel 2 107 71 3 176 86 5 148 80
NA Side Slough 2 336 446 1 65 - 1 153 - 1 47 - 1 201 - 2 19 1 3 104 67 11 135 183
NA Upland Slough 2 61 34 2 122 78 2 36 25 4 50 13 10 64 44
NA Tributary Mouth 1 12 - 1 12 -
MR-8 NA Main Channel 2 1,239 892 2 1,239 892
NA Multi-Split Main Channel 3 22 4 1 11 - 4 72 36 9 441 671 17 255 517
NA Split Main Channel 1 681 - 1 681 -
NA Side Channel 1 114 - 1 114 -
NA Upland Slough 1 14 - 1 99 - 1 7 - 1 9 - 4 32 44
Total 18 90 77 10 284 266 1 6 - 2 7 7 10 168 225 20 111 115 5 164 122 30 78 73 7 76 67 4 29 4 65 219 331 100 427 819 272 254 546
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 62 October 2015
Table 5.1-20. Sample sizes and mean and standard deviation (sd) of mesohabitat length measurements in meters made among geomorphic reaches by macrohabitat in Middle River Focus Area mainstem habitats surveyed.
Geo-
morphic
Reach
Focus
Area Macrohabitat
Backwater Beaver Complex Boulder Riffle Cascade Clearwater Plume Dry Unspecified Pool Puddled Rapid Riffle Run/Glide All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mea
n SD n Mean SD n Mean SD n Mean SD n Mean SD n Mea
n SD n Mean SD n Mean SD
MR-1 FA-184 Main Channel 1 1,678 - 1 1,678 -
Side Channel 1 263 - 2 177 30 3 205 54
MR-2 FA-173 Main Channel 1 3,366 - 1 3,366 -
Side Channel 2 306 114 1 359 - 1 328 - 1 67 - 5 273 130
Side Slough 1 76 - 2 94 - 2 51 57 2 42 30 3 93 51 7 267 203 17 153 162
Upland Slough 4 97 19 6 80 83 2 180 211 2 45 23 9 90 75 23 92 81
Tributary Mouth 1 3 - 4 23 15 1 33 - 6 21 15
MR-5 FA-151 Main Channel 1 549 - 1 3,000 - 2 1,775 1,733
Tributary Mouth 1 25 - 1 90 - 2 29 20 1 37 - 5 42 29
MR-6 FA-144 Main Channel 2 443 39 2 815 184 4 629 241
Side Channel 1 112 - 2 93 98 5 320 347 3 246 10 11 240 242
Side Slough 1 134 - 4 146 68 2 169 27 1 158 - 1 86 - 2 73 54 11 131 55
Upland Slough 3 74 27 1 8 - 4 58 40
FA-141 Main Channel 1 120 - 1 393 - 3 434 395 5 363 311
Multi-Split Main Channel 2 22 5 3 218 20 5 527 320 10 333 304
Side Channel 1 85 - 1 115 - 1 108 - 3 103 16
Upland Slough 3 109 108 4 260 118 1 99 - 8 184 127
Tributary Mouth 3 31 13 2 33 27 5 32 16
FA-138 Main Channel 1 1,697 - 1 1,697 -
Multi-Split Main Channel 1 35 - 1 122 - 3 301 117 5 212 151
Side Channel 1 125 - 3 63 45 3 142 103 7 106 76
Side Slough 3 105 76 3 345 271 2 83 45 1 72 - 6 96 33 7 71 28 6 72 8 28 111 115
Upland Slough 2 68 76 1 51 - 6 7 4 12 30 18 5 14 4 7 32 13 33 27 24
FA-128 Main Channel 1 2,458 - 1 2,458 -
Side Channel 1 111 - 2 107 35 1 68 - 10 123 97 1 88 - 17 74 52 16 249 345 48 145 216
Side Slough 1 361 - 1 43 - 1 49 - 5 63 38 7 127 75 15 110 94
Upland Slough 4 78 92 6 86 120 10 83 104
Tributary Mouth 1 24 - 1 46 - 1 100 - 3 57 39
MR-7 FA-115 Main Channel 1 332 - 1 332 -
Split Main Channel 3 78 60 2 153 66 5 524 355 10 316 326
Side Channel 2 15 3 2 196 116 1 58 - 5 96 110
Upland Slough 1 341 - 6 231 370 4 102 133 1 27 - 3 15 7 3 29 15 18 127 233
Tributary Mouth 1 9 - 1 9 -
FA-113 Main Channel 1 56 - 1 1,031 - 2 544 690
Split Main Channel 1 80 - 1 170 - 5 428 709 5 368 560 12 352 556
Side Slough 2 170 90 1 113 - 3 139 32 1 120 - 3 111 67 10 132 52
Upland Slough 1 104 - 1 159 - 5 27 26 1 206 - 1 5 - 7 103 117 16 83 93
Tributary Mouth 1 6 - 1 6 -
MR-8 FA-104 Main Channel 1 1,734 - 1 1,734 -
Side Channel 1 23 - 2 38 45 1 113 - 3 107 79 1 125 - 5 151 118 3 695 712 16 219 360
Side Slough 3 51 54 8 22 17 13 71 102 6 54 29 6 37 25 2 66 47 38 51 65
Upland Slough 2 416 402 4 60 63 3 24 5 5 133 190 14 129 203
Total 26 85 83 29 207 222 3 209 296 42 76 82 3 80 17 85 80 83 18 101 93 1 90 - 90 121 212 123 329 559 420 172
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 63 October 2015
Table 5.1-21. Sample sizes and mean and standard deviation (sd) of mesohabitat percent gradient measurements made among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem habitats surveyed.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 2 - - 4 4.8 6.2 6 3.2 5.4
UR-4 NA 2 0.5 - 3 0.6 0.2 1 0.8 - 22 0.5 0.6 31 1.2 3.1 6 4.5 3.0 65 1.2 2.6
UR-5 NA 1 0.5 - 3 1.1 0.4 2 15.0 4.2 6 5.6 7.5
UR-6 NA 2 0.7 0.4 5 0.1 0.3 2 1.0 1.4 2 1.3 1.1 9 0.6 0.8 5 0.7 0.4 1 1.0 - 26 0.7 0.7
MR-2 NA 4 0.6 0.5 1 - - 3 0.5 0.5 3 2.7 1.2 11 1.1 1.2
MR-3 NA 1 - - 1 4.0 - 2 2.0 2.8
MR-5 NA 1 0.5 - 1 0.5 -
MR-6 NA 5 0.4 0.4 6 0.2 0.3 3 0.8 0.3 3 1.7 1.5 18 0.4 0.6 18 0.1 0.2 3 1.0 0.9 56 0.4 0.6
MR-7 NA 3 0.5 0.5 1 0.5 - 4 0.4 0.3 11 0.1 0.3 9 - - 1 3.0 - 29 0.3 0.6
MR-8 NA 1 0.5 - 17 0.5 0.6 1 0.5 - 1 0.4 - 4 - - 24 0.4 0.5
Focus Areas
MR-1 FA-184 (Watana Dam) 3 0.7 0.3 3 0.7 0.3
MR-2 FA-173 (Stephan Lake Complex) 11 0.1 0.3 23 0.6 0.5 5 1.3 0.8 39 0.6 0.6
MR-5 FA-151 (Portage Creek) 2 - - 5 1.4 0.8 7 1.0 1.0
MR-6 FA-144 (Slough 21) 3 0.5 - 11 0.9 0.9 9 0.1 0.2 4 - - 27 0.4 0.7
FA-141 (Indian River) 5 0.5 0.4 10 0.7 0.6 3 0.8 1.0 8 - - 5 0.1 0.2 31 0.4 0.5
FA-138 (Gold Creek) 4 1.0 0.7 6 0.7 0.3 27 0.3 0.6 30 0.5 1.7 67 0.5 1.2
FA-128 (Slough 8A) 42 0.8 0.8 15 0.8 0.8 10 - - 3 2.3 2.5 70 0.8 1.0
MR-7 FA-115 (Slough 6A) 1 - - 8 0.3 0.3 5 0.7 1.0 18 0.2 0.5 32 0.3 0.6
FA-113 (Oxbow 1) 2 - - 11 0.7 0.5 9 0.1 0.2 15 0.1 0.2 37 0.3 0.4
MR-8 FA-104 (Whiskers Slough) 15 0.4 0.7 38 0.8 1.6 14 0.8 1.4 67 0.7 1.4
Total1 30 0.4 0.4 42 0.5 0.6 31 0.6 0.5 100 0.7 0.8 172 0.5 1.0 192 0.5 1.5 39 3.0 4.0 606 0.7 1.6
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 64 October 2015
Table 5.1-22. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat Bankfull Width in meters made among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem habitats surveyed.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 9 155.6 50.6 3 6.4 3.5 4 47.6 36.9 16 100.6 77.3
UR-4 NA 5 181.3 9.5 5 181.5 79.0 2 111.0 76.3 21 69.3 74.3 29 10.8 13.3 4 8.7 6.4 66 58.2 76.6
UR-5 NA 1 122.7 - 3 40.9 30.3 4 61.3 47.8
UR-6 NA 2 396.8 137.9 5 111.6 25.0 2 178.9 44.5 2 67.7 61.8 8 33.1 62.8 5 6.7 2.5 1 19.6 - 25 85.4 119.1
MR-2 NA 4 158.8 23.0 1 192.0 - 3 3.6 1.0 3 42.9 33.0 11 87.9 78.8
MR-3 NA 2 163.0 21.7 1 123.0 - 2 70.1 6.5 2 17.3 3.5 7 89.1 62.8
MR-5 NA 1 114.7 - 1 114.7 -
MR-6 NA 6 179.0 56.0 7 62.7 37.8 3 142.2 55.3 4 91.7 91.2 19 8.6 3.0 18 12.9 8.5 3 15.9 7.6 60 45.8 65.1
MR-7 NA 7 231.2 40.7 4 139.0 38.9 5 42.6 10.4 11 18.2 19.6 9 16.7 13.8 36 76.0 89.3
MR-8 NA 2 299.7 144.2 13 54.0 42.4 1 94.2 - 1 44.7 - 4 20.0 10.4 21 72.4 90.2
Focus Areas
MR-1 FA-184 (Watana Dam) 1 164.2 - 3 64.3 27.2 4 89.3 54.6
MR-2 FA-173 (Stephan Lake Complex) 1 189.2 - 2 103.6 103.4 15 44.7 62.9 23 12.3 8.2 5 3.8 3.3 46 29.7 51.1
MR-5 FA-151 (Portage Creek) 2 148.4 2.1 5 72.6 20.8 7 94.3 40.7
MR-6 FA-144 (Slough 21) 4 188.4 59.2 10 62.8 36.5 10 37.3 27.4 4 12.6 1.6 28 64.5 63.5
FA-141 (Indian River) 4 243.4 78.4 8 100.9 49.4 3 30.2 13.5 7 12.7 4.4 5 44.3 35.6 27 80.8 87.0
FA-138 (Gold Creek) 1 192.0 - 4 112.3 31.1 7 43.9 11.4 27 27.1 12.5 30 9.0 5.9 69 28.3 33.6
FA-128 (Slough 8A) 1 227.7 - 45 42.5 30.2 15 23.3 6.5 10 9.4 3.9 3 8.9 2.4 74 36.8 35.8
MR-7 FA-115 (Slough 6A) 1 211.7 - 7 141.9 41.3 5 17.2 6.5 18 7.4 8.8 31 45.9 67.0
FA-113 (Oxbow 1) 1 147.9 - 12 88.0 55.0 10 26.3 10.0 10 7.9 9.5 33 46.9 51.5
MR-8 FA-104 (Whiskers Slough) 1 186.7 - 13 46.1 28.2 37 11.5 7.5 13 10.6 6.2 64 21.1 28.8
Total1 54 198.1 71.6 37 79.0 46.2 37 128.4 58.6 107 49.3 37.1 177 28.9 41.3 183 10.7 9.1 35 31.0 31.0 630 50.7 66.7
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 65 October 2015
Table 5.1-23. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat wetted width in meters made among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem habitats surveyed.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 9 149.1 47.4 3 2.6 2.1 4 9.9 5.2 16 86.8 80.8
UR-4 NA 5 163.4 19.2 5 127.6 54.5 2 70.7 22.1 22 15.3 15.6 27 5.9 5.6 7 5.2 5.3 68 31.3 52.5
UR-5 NA 1 118.4 - 3 35.2 29.2 2 7.3 4.4 6 39.8 44.9
UR-6 NA 2 356.8 166.8 5 80.1 18.3 2 140.8 16.7 2 23.8 4.3 8 3.9 2.3 5 3.0 2.6 1 8.5 - 25 59.1 107.7
MR-2 NA 4 138.2 25.3 1 19.3 - 1 1.5 - 3 12.5 10.2 9 67.9 68.8
MR-3 NA 2 152.2 19.2 1 107.0 - 2 56.0 6.2 2 7.6 0.5 7 76.9 62.1
MR-5 NA 1 110.7 - 1 110.7 -
MR-6 NA 6 138.4 83.4 7 42.5 43.6 4 108.8 43.2 4 63.6 54.3 14 2.7 1.6 18 9.7 11.2 3 11.1 5.6 56 36.8 57.2
MR-7 NA 7 187.6 92.9 4 100.2 48.8 5 31.4 4.5 10 11.6 20.9 10 10.6 7.8 1 8.6 - 37 56.8 81.3
MR-8 NA 2 276.7 139.9 17 30.5 33.3 1 70.5 - 1 33.3 - 4 11.8 14.8 25 48.9 80.0
Focus Areas
MR-1 FA-184 (Watana Dam) 1 160.3 - 3 50.2 20.8 4 77.8 57.6
MR-2 FA-173 (Stephan Lake Complex) 1 181.8 - 2 5.6 1.3 15 12.4 14.0 17 6.4 4.6 6 3.5 3.3 41 12.4 28.7
MR-5 FA-151 (Portage Creek) 2 131.8 3.8 5 10.5 8.2 7 45.2 59.6
MR-6 FA-144 (Slough 21) 4 168.0 50.1 11 25.7 25.9 9 15.5 13.0 3 6.6 1.6 27 41.3 59.5
FA-141 (Indian River) 5 165.2 142.1 10 83.6 47.7 3 21.4 16.1 8 9.7 4.3 5 7.8 8.6 31 59.4 82.0
FA-138 (Gold Creek) 1 184.0 - 4 78.8 27.7 7 20.1 6.3 26 15.5 9.0 29 4.0 2.7 67 17.3 28.3
FA-128 (Slough 8A) 1 175.5 - 45 26.0 22.6 14 13.8 4.9 10 3.9 3.9 2 6.8 4.6 72 22.1 27.1
MR-7 FA-115 (Slough 6A) 1 206.7 - 10 92.9 64.0 3 7.0 5.2 17 5.7 7.0 1 2.7 - 32 39.3 61.7
FA-113 (Oxbow 1) 2 98.6 89.9 11 62.8 49.0 9 14.6 7.5 11 5.7 5.3 1 3.5 - 34 31.9 43.8
MR-8 FA-104 (Whiskers Slough) 1 181.7 - 14 26.1 22.6 31 6.8 5.8 14 6.7 4.8 60 14.2 26.2
Total1 56 169.2 82.8 43 54.5 43.4 40 94.6 52.9 107 28.6 24.6 162 11.2 11.3 174 6.4 6.5 43 7.6 6.1 625 35.0 58.0
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 66 October 2015
Table 5.1-24. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat Bankfull Depth in meters made among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem habitats surveyed.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 9 2.6 1.2 3 0.5 0.5 4 1.4 0.6 16 1.9 1.2
UR-4 NA 5 2.8 1.0 5 1.1 0.1 2 1.1 0.0 21 0.9 0.6 26 0.7 0.3 4 0.7 0.2 64 1.0 0.7
UR-5 NA 1 1.3 - 3 1.4 0.2 4 1.4 0.2
UR-6 NA 2 2.1 0.3 5 1.1 0.3 2 2.1 0.6 2 0.9 0.1 8 0.9 0.1 5 0.9 0.4 1 1.1 - 25 1.1 0.5
MR-2 NA 4 3.2 0.9 1 1.5 - 1 0.7 - 3 1.0 0.4 9 2.0 1.3
MR-3 NA 2 2.2 0.1 1 2.2 - 2 2.4 0.8 1 0.6 - 6 2.0 0.8
MR-5 NA 1 3.0 - 1 3.0 -
MR-6 NA 6 4.1 3.2 7 1.2 0.7 3 2.0 1.7 4 1.7 0.9 17 1.2 0.4 17 0.9 0.3 3 1.4 0.6 57 1.5 1.4
MR-7 NA 4 2.2 1.3 4 2.7 0.6 5 0.9 0.1 10 0.9 0.3 10 0.8 0.3 1 0.3 - 34 1.2 0.9
MR-8 NA 2 2.9 1.4 12 0.9 0.6 1 1.6 - 1 0.8 - 4 0.9 0.3 20 1.1 0.8
Focus Areas
MR-1 FA-184 (Watana Dam) 1 2.3 - 3 1.5 0.9 4 1.7 0.8
MR-2 FA-173 (Stephan Lake Complex) 1 2.2 - 2 0.4 0.1 14 0.9 0.6 17 0.7 0.1 5 0.4 0.1 39 0.8 0.5
MR-5 FA-151 (Portage Creek) 2 1.9 0.2 5 1.7 0.3 7 1.8 0.3
MR-6 FA-144 (Slough 21) 4 2.8 0.2 9 1.2 0.3 9 1.2 0.4 4 1.7 1.7 26 1.5 0.9
FA-141 (Indian River) 3 2.2 1.2 8 1.7 0.4 3 0.7 0.1 7 1.0 0.3 5 1.3 0.6 26 1.3 0.7
FA-138 (Gold Creek) 1 2.6 - 4 1.7 0.7 7 1.1 0.6 27 1.0 0.4 28 1.1 0.4 67 1.1 0.5
FA-128 (Slough 8A) 1 2.1 - 41 1.2 0.5 14 1.3 0.2 10 0.8 0.1 2 0.7 0.2 68 1.2 0.4
MR-7 FA-115 (Slough 6A) 1 5.8 - 8 1.8 0.6 5 0.7 0.2 18 0.7 0.4 32 1.1 1.1
FA-113 (Oxbow 1) 2 1.7 1.5 12 1.2 0.7 10 1.0 0.8 9 0.5 0.2 1 0.2 - 34 0.9 0.7
MR-8 FA-104 (Whiskers Slough) 1 2.2 - 12 1.2 1.2 35 0.6 0.2 13 1.4 0.6 61 0.9 0.7
Total1 51 2.7 1.5 36 1.3 0.6 38 1.6 0.9 101 1.2 0.6 169 0.9 0.5 169 0.9 0.5 35 1.0 0.6 600 1.2 0.9
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 67 October 2015
Table 5.1-25. Sample sizes (n) and mean and standard deviation (sd) of mesohabitat thalweg depth in meters made among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem habitats surveyed.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 8 3.2 1.2 3 0.3 0.4 4 0.5 0.3 15 1.9 1.6
UR-4 NA 4 4.5 1.8 3 1.5 0.2 1 0.9 - 22 0.4 0.4 27 0.5 0.4 7 0.2 0.1 65 0.7 1.1
UR-5 NA 1 1.9 - 3 0.8 0.5 2 0.3 0.0 6 0.8 0.7
UR-6 NA 2 2.2 0.7 2 - - 2 2.1 0.3 2 0.6 0.1 8 0.3 0.2 5 0.4 0.4 1 0.5 - 22 0.7 0.8
MR-2 NA 4 2.9 0.6 1 0.8 - 1 0.4 - 2 0.5 0.2 8 1.7 1.3
MR-3 NA 2 2.7 0.3 1 2.8 - 2 1.8 - 2 0.3 0.2 7 1.8 1.1
MR-5 NA 1 2.7 - 1 2.7 -
MR-6 NA 6 3.9 4.5 6 0.8 0.8 4 3.0 2.1 4 1.1 0.7 13 0.3 0.2 15 0.5 0.4 3 0.5 0.3 51 1.1 2.0
MR-7 NA 4 1.9 1.4 4 2.3 1.5 5 0.5 0.1 9 0.4 0.3 10 0.7 0.4 1 0.3 - 33 0.9 1.0
MR-8 NA 2 3.2 0.1 17 0.5 0.4 1 1.1 - 1 0.6 - 3 0.4 0.3 24 0.8 0.8
Focus Areas
MR-1 FA-184 (Watana Dam) 1 2.9 - 3 1.6 0.8 4 1.9 0.9
MR-2 FA-173 (Stephan Lake Complex) 1 2.8 - 2 0.1 0.0 15 0.8 1.4 17 0.4 0.2 6 0.2 0.1 41 0.5 1.0
MR-5 FA-151 (Portage Creek) 1 2.9 - 4 0.4 0.3 5 0.9 1.1
MR-6 FA-144 (Slough 21) 4 2.3 0.2 10 0.5 0.4 9 0.5 0.2 3 0.7 0.3 26 0.8 0.7
FA-141 (Indian River) 3 1.6 1.3 4 0.7 0.3 3 0.7 0.5 8 0.8 0.4 4 0.5 0.2 22 0.8 0.6
FA-138 (Gold Creek) 3 0.8 0.2 7 0.5 0.2 25 0.4 0.2 29 0.4 0.3 64 0.4 0.3
FA-128 (Slough 8A) 1 2.6 - 43 0.7 0.8 14 0.4 0.3 10 0.3 0.3 2 0.3 0.2 70 0.6 0.7
MR-7 FA-115 (Slough 6A) 1 7.3 - 10 1.0 0.7 3 0.3 0.0 16 0.5 0.3 1 0.1 - 31 0.8 1.3
FA-113 (Oxbow 1) 2 1.3 0.9 11 0.9 1.0 7 0.4 0.3 11 0.3 0.2 1 0.3 - 32 0.6 0.7
MR-8 FA-104 (Whiskers Slough) 1 1.9 - 14 0.6 0.9 29 0.3 0.2 14 0.7 0.6 58 0.5 0.6
Total1 47 2.9 2.0 32 0.6 0.5 38 1.5 1.2 103 0.7 0.7 155 0.4 0.5 169 0.5 0.4 40 0.3 0.2 585 0.8 1.1
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FERC Project No. 14241 Page 68 October 2015
Table 5.1-26. Sample sizes (n) and mean and standard deviation (sd) of maximum pool depth in meters among geomorphic reaches by macrohabitat in Upper River and Middle River mainstem habitats surveyed.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 8 1.2 3 1.3 0.4 4 0.3 15 1.3 1.6
UR-4 NA 4 1.8 3 0.2 1 - 22 0.9 0.4 27 1.2 0.4 7 0.8 0.1 64 1.1 1.1
UR-5 NA 1 - 3 0.5 2 0.0 6 0.7
UR-6 NA 2 0.7 2 - - 2 0.3 2 0.1 8 0.6 0.2 5 1.5 0.4 1 - 22 0.8 0.8
MR-2 NA 4 0.6 1 - 1 0.7 - 2 0.2 8 0.7 1.3
MR-3 NA 2 0.3 1 - 2 - 2 0.2 7 1.1
MR-5 NA 1 - 1 -
MR-6 NA 6 4.5 6 1.4 0.8 4 2.1 4 0.7 13 0.6 0.2 15 0.9 0.4 3 0.3 51 0.8 2.0
MR-7 NA 4 1.4 4 1.5 5 0.1 9 1.2 0.3 10 0.8 0.4 1 - 33 1.0 1.0
MR-8 NA 2 0.1 17 0.5 0.4 1 - 1 - 3 0.4 0.3 24 0.4 0.8
Focus Areas
MR-1 FA-184 (Watana Dam) 1 - 3 0.8 4 0.9
MR-2 FA-173 (Stephan Lake Complex) 1 - 2 0.0 15 0.5 1.4 17 0.7 0.2 6 0.3 0.1 41 0.6 1.0
MR-5 FA-151 (Portage Creek) 1 - 4 0.9 0.3 5 0.9 1.1
MR-6 FA-144 (Slough 21) 4 0.2 10 0.5 0.4 9 1.0 0.2 3 1.0 0.3 26 0.9 0.7
FA-141 (Indian River) 3 0.5 1.3 4 0.9 0.3 3 1.1 0.5 8 0.6 0.4 4 0.8 0.2 22 0.8 0.6
FA-138 (Gold Creek) 3 0.9 0.2 7 1.3 0.2 25 0.9 0.2 29 0.7 0.3 64 0.8 0.3
FA-128 (Slough 8A) 1 - 43 1.1 0.8 14 0.9 0.3 10 0.7 0.3 2 0.6 0.2 70 1.0 0.7
MR-7 FA-115 (Slough 6A) 1 - 10 0.9 0.7 3 0.5 0.0 16 0.9 0.3 1 - 31 0.8 1.3
FA-113 (Oxbow 1) 2 1.0 0.9 11 0.7 1.0 7 0.7 0.3 11 0.5 0.2 1 - 32 0.7 0.7
MR-8 FA-104 (Whiskers Slough) 1 - 14 0.6 0.9 29 0.5 0.2 14 1.6 0.6 58 0.7 0.6
Total1 47 0.8 2.0 32 0.7 0.5 38 0.9 1.2 103 0.9 0.7 155 0.7 0.5 169 0.9 0.4 40 0.7 0.2 584 0.8 1.1
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FERC Project No. 14241 Page 69 October 2015
Table 5.1-27. Sample sizes (n) and mean and standard deviation (sd) of percent erosion along mesohabitat units in Upper River and Middle River mainstem habitats surveyed by macrohabitat.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 8 6.7 1.2 3 - 0.4 4 24.4 0.3 15 9.8 1.6
UR-4 NA 4 14.0 1.8 3 6.0 0.2 1 25.0 - 22 - 0.4 27 - 0.4 7 8.8 0.1 64 3.1 1.1
UR-5 NA 1 - - 3 - 0.5 2 - 0.0 6 - 0.7
UR-6 NA 2 1.3 0.7 2 15.2 - 2 22.0 0.3 2 25.0 0.1 8 - 0.2 5 - 0.4 1 - - 22 6.6 0.8
MR-2 NA 4 8.8 0.6 1 - - 1 - - 2 - 0.2 8 3.2 1.3
MR-3 NA 2 17.5 0.3 1 - - 2 13.8 - 2 - 0.2 7 8.9 1.1
MR-5 NA 1 - - 1 - -
MR-6 NA 6 2.1 4.5 6 5.7 0.8 4 1.3 2.1 4 10.0 0.7 13 1.8 0.2 15 - 0.4 3 5.0 0.3 51 2.4 2.0
MR-7 NA 4 11.1 1.4 4 5.0 1.5 5 6.0 0.1 9 2.2 0.3 10 - 0.4 1 - - 33 4.0 1.0
MR-8 NA 2 7.5 0.1 17 5.1 0.4 1 5.0 - 1 10.0 - 3 - 0.3 24 4.7 0.8
Focus Areas
MR-1 FA-184 (Watana Dam) 1 10.0 - 3 23.3 0.8 4 20.0 0.9
MR-2 FA-173 (Stephan Lake Complex) 1 15.0 - 2 - 0.0 15 - 1.4 17 - 0.2 6 - 0.1 41 0.3 1.0
MR-5 FA-151 (Portage Creek) 1 1.3 - 4 - 0.3 5 0.4 1.1
MR-6 FA-144 (Slough 21) 4 38.8 0.2 10 3.0 0.4 9 22.5 0.2 3 2.5 0.3 26 15.0 0.7
FA-141 (Indian River) 3 7.0 1.3 4 7.8 0.3 3 16.7 0.5 8 - 0.4 4 11.0 0.2 22 7.0 0.6
FA-138 (Gold Creek) 30.0 3 14.0 0.2 7 24.3 0.2 25 1.3 0.2 29 4.4 0.3 64 6.3 0.3
FA-128 (Slough 8A) 1 - - 43 26.9 0.8 14 1.8 0.3 10 - 0.3 2 85.0 0.2 70 21.3 0.7
MR-7 FA-115 (Slough 6A) 1 5.0 - 10 4.5 0.7 3 7.0 0.0 16 0.3 0.3 1 - 31 2.6 1.3
FA-113 (Oxbow 1) 2 - 0.9 11 10.3 1.0 7 4.0 0.3 11 - 0.2 1 - - 32 4.2 0.7
MR-8 FA-104 (Whiskers Slough) 1 55 - 14 4.5 0.9 29 1.5 0.2 14 3.2 0.6 58 3.3 0.6
Total1 47 11.0 2.0 32 7.8 0.5 38 6.6 1.2 103 17.2 0.7 155 2.5 0.5 169 1.0 0.4 40 11.2 0.2 584 6.4 1.1
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FERC Project No. 14241 Page 70 October 2015
Table 5.1-28. Sample sizes (n) and mean and standard deviation (sd) of percent undercut banks along mesohabitat units in Upper River and Middle River mainstem habitats surveyed by macrohabitat.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 8 0.6 1.2 3 - 0.4 4 - 0.3 15 0.3 1.6
UR-4 NA 4 - 1.8 3 - 0.2 1 - - 22 0.5 0.4 27 - 0.4 7 3.8 0.1 65 0.6 1.1
UR-5 NA 1 - - 3 - 0.5 2 - 0.0 6 - 0.7
UR-6 NA 2 - 0.7 2 - - 2 - 0.3 2 - 0.1 8 0.3 0.2 5 - 0.4 1 - - 22 0.1 0.8
MR-2 NA 4 - 0.6 1 - - 1 - - 2 - 0.2 8 - 1.3
MR-3 NA 2 7.5 0.3 1 - - 2 - - 2 - 0.2 7 2.1 1.1
MR-5 NA 1 - - 1 - -
MR-6 NA 6 - 4.5 6 0.7 0.8 4 - 2.1 4 - 0.7 13 - 0.2 15 6.7 0.4 3 6.7 0.3 51 2.4 2.0
MR-7 NA 4 - 1.4 4 - 1.5 5 - 0.1 9 - 0.3 10 - 0.4 1 - - 33 - 1.0
MR-8 NA 2 - 0.1 17 0.3 0.4 1 - - 1 - - 3 - 0.3 24 0.2 0.8
Focus Areas
MR-1 FA-184 (Watana Dam) 1 - - 3 - 0.8 4 - 0.9
MR-2 FA-173 (Stephan Lake Complex) 1 - - 2 - 0.0 15 0.1 1.4 17 0.4 0.2 6 10.4 0.1 41 1.6 1.0
MR-5 FA-151 (Portage Creek) 1 - - 4 - 0.3 5 - 1.1
MR-6 FA-144 (Slough 21) 4 - 0.2 10 1.7 0.4 9 8.0 0.2 3 - 0.3 26 3.5 0.7
FA-141 (Indian River) 3 9.0 1.3 4 2.5 0.3 3 - 0.5 8 2.5 0.4 4 4.0 0.2 22 3.6 0.6
FA-138 (Gold Creek) 15.0 3 11.0 0.2 7 9.2 0.2 25 3.9 0.2 29 1.8 0.3 64 4.2 0.3
FA-128 (Slough 8A) 1 - - 43 5.9 0.8 14 - 0.3 10 2.5 0.3 2 - 0.2 70 4.0 0.7
MR-7 FA-115 (Slough 6A) 1 - - 10 2.5 0.7 3 1.0 0.0 16 - 0.3 1 - 31 0.9 1.3
FA-113 (Oxbow 1) 2 - 0.9 11 1.3 1.0 7 0.5 0.3 11 - 0.2 1 - - 32 0.5 0.7
MR-8 FA-104 (Whiskers Slough) 1 0 - 14 0.0 0.9 29 0.5 0.2 14 0.0 0.6 58 0.3 0.6
Total1 47 1.4 2.0 32 2.1 0.5 38 1.0 1.2 103 3.3 0.7 155 1.2 0.5 169 1.1 0.4 40 3.0 0.2 585 1.7 1.1
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FERC Project No. 14241 Page 71 October 2015
Table 5.1-29. Sample sizes (n) and mean and standard deviation (sd) of large woody debris counts within mesohabitat units in mainstem habitats.
Geomorphic
Reach Focus Area Main Channel Multi-Split Main Channel Split Main Channel Side Channel Side Slough Upland Slough Tributary Mouth All Measured Units
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Non-Focus Areas
UR-3 NA 4 2.3 0.6 1 2.0 - 1 5.0 - 2 0.3 0.2 8 2.5 1.3
UR-4 NA 2 20.5 0.3 1 9.0 - 2 2.5 - 2 - 0.2 7 7.9 1.1
UR-5 NA 1 10.0 - 1 10.0 -
UR-6 NA 6 23.2 4.5 6 6.7 0.8 4 2.8 2.1 4 6.8 0.7 13 1.3 0.2 15 16.3 0.4 3 - 0.3 51 8.6 2.0
MR-2 NA 4 13.1 1.4 4 9.3 1.5 5 12.8 0.1 9 10.6 0.3 10 15.4 0.4 1 - - 33 12.2 1.0
MR-3 NA 2 66.5 0.1 17 6.1 0.4 1 17.0 - 1 57.0 - 3 6.3 0.3 24 13.4 0.8
MR-5 NA 8 4.7 1.2 3 0.7 0.4 4 0.5 0.3 15 2.9 1.6
MR-6 NA 4 3.2 1.8 3 2.8 0.2 1 2.0 - 22 0.2 0.4 27 1.9 0.4 7 0.9 0.1 64 1.4 1.1
MR-7 NA 1 4.0 - 3 1.3 0.5 2 2.5 0.0 6 2.2 0.7
MR-8 NA 2 28.0 0.7 2 25.8 - 2 17.0 0.3 2 - 0.1 8 1.9 0.2 5 4.2 0.4 1 1.0 - 22 9.6 0.8
Focus Areas
MR-1 FA-184 (Watana Dam) 1 - - 3 0.3 0.8 4 0.3 0.9
MR-2 FA-173 (Stephan Lake Complex) 1 20.0 - 2 - 0.0 15 2.7 1.4 17 5.7 0.2 6 0.7 0.1 41 4.3 1.0
MR-5 FA-151 (Portage Creek) 1 - - 4 0.6 0.3 5 0.4 1.1
MR-6 FA-144 (Slough 21) 4 84.3 0.2 10 11.7 0.4 9 9.3 0.2 3 30.0 0.3 26 21.6 0.7
FA-141 (Indian River) 3 8.4 1.3 4 16.8 0.3 3 5.0 0.5 8 17.8 0.4 4 3.4 0.2 22 11.9 0.6
FA-138 (Gold Creek) 35.0 3 2.2 0.2 7 18.0 0.2 25 4.9 0.2 29 4.8 0.3 64 6.2 0.3
FA-128 (Slough 8A) 1 70.0 - 43 7.7 0.8 14 3.2 0.3 10 6.0 0.3 2 - 0.2 70 7.2 0.7
MR-7 FA-115 (Slough 6A) 1 2.0 - 10 5.8 0.7 3 1.0 0.0 16 4.0 0.3 1 - - 31 3.9 1.3
FA-113 (Oxbow 1) 2 18.5 0.9 11 6.3 1.0 7 8.0 0.3 11 6.0 0.2 1 3.0 - 32 7.2 0.7
MR-8 FA-104 (Whiskers Slough) 1 60 - 14 8.1 0.9 29 2.6 0.2 14 27.2 0.6 58 9.9 0.6
Total1 47 19.0 2.0 32 9.9 0.5 38 6.6 1.2 103 8.2 0.7 155 3.7 0.5 169 8.7 0.4 40 1.0 0.2 584 7.6 1.1
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FERC Project No. 14241 Page 72 October 2015
Table 5.2-1. Sum of length (m) surveyed, and composition by length of mesohabitats in Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Length (m) &
Percent n Length (m) &
Percent n Length (m) & Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) & Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length
Tsusena Creek Tsusena-1 - 2 212 32% 1 28 4% 1 87 13% 2 84 13% 2 260 39% 8 671
Unnamed 184.0 184.0-1 - 1 16 100% 1 16
Fog Creek Fog-4 - 5 716 55% 7 263 20% 6 238 18% 2 79 6% 20 1,297
Fog Creek Fog-3 - 5 292 15% 1 28 1% 6 750 40% 7 663 35% 4 156 8% 23 1,889
Fog Creek Fog-2 - 4 410 59% 3 122 18% 2 136 20% 1 24 4% 10 692
Fog Creek Fog-1 - 3 342 24% 1 35 2% 2 39 3% 3 338 24% 10 559 39% 3 108 8% 22 1,422
Unnamed 173.8 NA FA-173 3 867 84% 3 17 2% 3 153 15% 9 1,037
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 5 1% 1 45 9% 1 36 7% 5 352 71% 6 56 11% 14 494
Chinook Creek Chinook-1 - 5 185 33% 5 341 60% 2 39 7% 12 564
Cheechako Creek Cheechako-1 - 1 40 6% 4 385 57% 1 23 3% 4 80 12% 3 144 21% 13 673
Devils Canyon lower extent
Portage Creek NA FA-151 1 97 33% 1 135 46% 1 62 21% 3 295
Unnamed 144.6 NA FA-144 1 84 100% 1 84
Indian River NA FA-141 2 8 1% 1 26 3% 3 78 9% 8 363 42% 7 395 45% 21 870
Gold Creek NA - 2 35 8% 5 339 73% 4 89 19% 11 463
Fourth of July Creek NA - 2 32 21% 1 47 31% 2 42 28% 2 30 20% 7 151
Sherman Creek NA - 1 14 28% 2 23 44% 1 14 28% 4 52
Skull Creek NA FA-128 1 23 34% 1 23 35% 1 20 31% 3 66
Fifth of July Creek NA - 1 27 100% 1 27
Deadhorse Creek NA - 1 9 63% 1 5 37% 2 14
Little Portage Creek NA - 1 24 100% 1 24
McKenzie Creek NA - 1 21 55% 1 17 45% 2 37
Lane Creek NA - 1 70 100% 1 70
Unnamed 115.4 NA FA-115 2 255 54% 4 55 12% 3 159 34% 9 469
Gash Creek NA FA-113 1 26 100% 1 26
Slash Creek NA FA-113 1 5 3% 3 56 31% 3 34 19% 3 83 47% 10 178
Unnamed 113.7 NA FA-113 1 17 100% 1 17
Chase Creek NA - 1 28 10% 1 12 4% 1 234 85% 3 274
Whiskers Creek NA FA-104 1 2 0.11% 16 761 41% 14 398 21% 18 708 38% 49 1,868
Total1 4 15 0.11% 1 26 0% 26 2,949 21% 15 696 5% 1 23 0.17% 2 105 1% 1 36 0.26% 41 1,518 11% 37 2,614 19% 73 3,258 24% 61 2,497 18% 262 13,738
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Table 5.2-2. Mean (±SD) percent gradient of mesohabitats in Middle River tributaries.
Tributary Name Geomorphic Reach Focus Area Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 1.5 0.7 1 0.0 - 1 3.0 - 2 1.0 0.0 2 1.0 0.0 8 1.3 0.9
Unnamed 184.0 184.0-1 - 1 1.0 - 1 1.0 -
Fog Creek Fog-4 - 5 3.1 0.9 7 2.7 0.5 6 2.1 0.7 2 1.0 0.0 20 2.5 0.9
Fog Creek Fog-3 - 5 3.2 0.3 1 4.0 - 6 3.5 0.8 7 1.9 0.6 4 1.3 0.3 23 2.6 1.1
Fog Creek Fog-2 - 4 2.8 1.5 3 0.2 0.3 2 3.3 0.4 1 2.0 - 10 2.0 1.6
Fog Creek Fog-1 - 3 2.0 1.0 1 3.0 - 2 0.0 0.0 2 2.5 0.7 9 2.0 0.4 3 0.3 0.6 20 1.7 1.0
Unnamed 173.8 NA FA-173 3 3.0 1.0 2 1.5 0.7 5 2.4 1.1
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 2.0 - 1 1.5 - 5 2.1 0.2 3 1.3 0.6 10 1.8 0.5
Chinook Creek Chinook-1 - 5 4.4 0.5 5 3.1 1.1 2 1.0 0.0 12 3.3 1.5
Cheechako Creek Cheechako-1 - 1 3.0 - 4 7.4 0.5 1 10.0 - 4 0.8 0.6 3 4.3 0.6 13 4.5 3.2
Devils Canyon lower extent
Portage Creek NA FA-151 1 1.0 - 1 1.0 - 1 0.0 - 3 0.7 0.6
Unnamed 144.6 NA FA-144 1 4.8 - 1 4.8 -
Indian River NA FA-141 1 0 - 2 0.3 0.5 8 1.9 1.6 6 0.5 0.5 17 1.1 1.4
Gold Creek NA - 2 5.0 2.8 4 4.0 0.7 4 2.1 0.9 10 3.5 1.7
Fourth of July Creek NA - 2 0.5 0.7 1 2.0 - 1 2.0 - 2 1.0 0.0 6 1.2 0.8
Sherman Creek NA - 1 10.0 - 1 0.0 - 1 0.5 - 3 3.5 5.6
Skull Creek NA FA-128 1 0.0 - 1 2.0 - 1 1.0 - 3 1.0 1.0
Fifth of July Creek NA - 1 4.9 - 1 4.9 -
Deadhorse Creek NA - 0
Little Portage Creek NA - 1 4.0 - 1 4.0 -
McKenzie Creek NA - 1 6.5 - 1 1.5 - 2 4.0 3.5
Lane Creek NA - 1 2.5 - 1 2.5 -
Unnamed 115.4 NA FA-115 1 0.0 - 2 2.0 1.4 1 0.0 - 4 1.0 1.4
Gash Creek NA FA-113 1 3.0 - 1 3.0 -
Slash Creek NA FA-113 1 0.0 - 1 2.0 - 3 0.5 0.5 5 0.7 0.8
Unnamed 113.7 NA FA-113 1 7.0 - 1 7.0 -
Chase Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Whiskers Creek NA FA-104 15 0.0 0.1 12 0.9 0.5 18 0.1 0.2 45 0.3 0.5
Total1 1 0 - 25 2.7 1.0 14 5.7 2.0 1 10.0 - 2 5.7 1.2 1 1.5 - 33 0.2 0.4 36 3.1 1.1 61 1.8 1.1 54 0.6 0.7 228 1.9 1.8
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Table 5.2-3. Mean (±SD) bankfull width (m) of mesohabitats in Middle River tributaries.
Tributary Name Geomorphic
Reach Focus Area Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - \ 2 22.6 5.1 1 6.7 - 1 28.7 - 2 7.4 7.2 2 11.6 8.2 8 14.8 9.7
Unnamed 184.0 184.0-1 - 1 33.4 - 1 33.4 -
Fog Creek Fog-4 - 5 9.4 1.8 7 8.9 2.1 6 8.1 2.1 2 12.8 2.3 20 9.2 2.3
Fog Creek Fog-3 - 5 18.1 4.1 1 14.6 - 6 15.7 6.4 7 18.4 5.5 4 14.9 2.2 23 16.9 4.9
Fog Creek Fog-2 - 4 20.4 5.6 3 15.1 2.8 2 17.8 3.6 1 14.7 - 10 17.7 4.5
Fog Creek Fog-1 - 3 28.8 16.5 1 18.5 - 2 11.2 6.5 2 22.9 0.3 9 13.6 8.6 3 16.1 7.4 20 17.2 10.1
Unnamed 173.8 NA FA-173 3 7.7 1.7 3 4.5 1.8 3 5.3 0.6 9 5.8 1.9
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 2.6 - 1 5.1 - 1 3.4 - 5 8.3 1.2 6 6.7 3.8 14 6.6 3.1
Chinook Creek Chinook-1 - 5 9.6 3.7 5 9.2 1.3 2 8.3 0.4 12 9.2 2.4
Cheechako Creek Cheechako-1 - 1 13.9 - 4 14.8 3.4 1 6.9 - 4 13.0 2.2 3 14.6 3.1 13 13.5 3.2
Devils Canyon lower extent
Portage Creek NA FA-151 1 30.4 - 1 33.2 - 1 34.8 - 3 32.8 2.2
Unnamed 144.6 NA FA-144 1 19.4 - 1 19.4 -
Indian River NA FA-141 1 5.2 - 3 8.3 7.7 8 13.2 7.2 7 15.9 13.2 19 13.0 9.8
Gold Creek NA - 2 9.7 1.2 4 11.8 1.0 4 12.2 2.4 10 11.5 1.9
Fourth of July Creek NA - 2 6.6 0.8 1 5.6 - 2 8.5 1.8 2 6.9 1.7 7 7.1 1.5
Sherman Creek NA - 1 7.3 - 2 6.0 2.8 1 8.0 - 4 6.8 1.9
Skull Creek NA FA-128 1 12.4 - 1 7.9 - 1 11.8 - 3 10.7 2.4
Fifth of July Creek NA - 1 20.1 - 1 20.1 -
Deadhorse Creek NA -
Little Portage Creek NA - 1 3.8 - 1 3.8 -
McKenzie Creek NA - 1 7.5 - 1 5.5 - 2 6.5 1.4
Lane Creek NA - 1 8.0 - 1 8.0 -
Unnamed 115.4 NA FA-115 2 3.1 2.7 4 1.1 0.3 3 1.7 0.9 9 1.7 1.3
Gash Creek NA FA-113 1 4.4 - 1 4.4 -
Slash Creek NA FA-113 1 2.0 - 3 4.0 1.4 3 4.3 2.1 3 4.6 2.7 10 4.1 1.9
Unnamed 113.7 NA FA-113 1 7.5 - 1 7.5 -
Chase Creek NA - 1 9.7 - 1 4.3 - 2 7.0 3.8
Whiskers Creek NA FA-104 1 2.8 - 16 8.0 3.1 14 6.9 1.5 18 6.8 1.8 49 7.1 2.3
Total1 2 2.7 0.2 1 5.2 - 25 17.0 9.7 15 11.8 5.4 1 6.9 - 2 13.5 8.4 1 3.4 - 41 8.4 4.4 36 12.7 6.7 70 10.0 6.9 60 9.8 7.3 254 10.8 7.2
1Total number of measurements (n) and group mean (SD) for each mesohabitat type per River Segment.
2Total number of measurement (n) and group mean (SD) for each geomorphic reach.
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
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FERC Project No. 14241 Page 75 October 2015
Table 5.2-4. Mean (±SD) wetted width (m) of mesohabitats in Middle River tributaries.
Tributary Name Geomorphic
Reach Focus Area Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 18.6 6.8 1 2.7 - 1 23.2 - 2 5.5 6.8 2 8.7 9.7 8 11.4 9.1
Unnamed 184.0 184.0-1 - 1 29.8 - 1 29.8 -
Fog Creek Fog-4 - 5 7.3 1.3 7 6.8 1.5 6 7.0 1.4 2 9.4 0.6 20 7.3 1.5
Fog Creek Fog-3 - 5 16.5 4.3 1 12.6 - 6 13.7 5.9 7 16.2 5.6 4 11.6 1.6 23 14.6 4.9
Fog Creek Fog-2 - 4 16.7 6.4 3 12.4 3.2 2 15.1 4.0 1 12.4 - 10 14.7 4.7
Fog Creek Fog-1 - 3 21.2 10.5 1 13.9 - 2 5.7 1.5 2 21.2 1.4 9 9.7 6.5 3 13.9 8.4 20 13.0 8.1
Unnamed 173.8 NA FA-173 3 4.3 1.0 3 3.0 1.1 3 4.0 0.7 9 3.8 1.1
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 1.8 - 1 4.2 - 1.0 1.6 - 5 7.4 1.1 6 4.0 2.3 14 4.9 2.6
Chinook Creek Chinook-1 - 5 8.5 3.1 5 8.0 1.0 2 7.0 0.0 12 8.0 2.1
Cheechako Creek Cheechako-1 - 1 11.3 - 4 10.7 2.0 1 5.1 - 4 9.8 2.2 3 10.8 1.9 13 10.1 2.3
Devils Canyon lower extent
Portage Creek NA FA-151 1 19.3 - 1 27.2 - 1 24.1 - 3 23.5 4.0
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 2.0 - 1 4.5 - 3 4.6 3.6 8 8.3 6.5 7 6.5 5.3 20 6.6 5.4
Gold Creek NA - 2 8.1 0.1 5 9.5 1.5 4 8.7 1.4 11 8.9 1.3
Fourth of July Creek NA - 2 4.6 0.5 1 4.8 - 2 6.1 1.7 2 4.3 0.4 7 5.0 1.1
Sherman Creek NA - 1 4.0 - 2 2.7 1.1 1 1.5 - 4 2.7 1.2
Skull Creek NA FA-128 1 10.3 - 1 3.3 - 1 7.6 - 3 7.1 3.5
Fifth of July Creek NA - 1 5.5 - 1 5.5 -
Deadhorse Creek NA - 1 6.6 - 1 4.5 - 2 5.6 1.5
Little Portage Creek NA - 1 2.1 - 1 2.1 -
McKenzie Creek NA - 1 1.4 - 1 1.4 -
Lane Creek NA - 1 4.6 - 1 4.6 -
Unnamed 115.4 NA FA-115 2 2.4 2.2 4 0.8 0.1 3 1.1 0.4 9 1.3 1.0
Gash Creek NA FA-113 1 2.4 - 1 2.4 -
Slash Creek NA FA-113 1 1.3 - 3 2.8 1.1 3 1.8 0.3 3 1.6 0.3 10 2.0 0.8
Unnamed 113.7 NA FA-113 1 3.1 - 1 3.1 -
Chase Creek NA - 1 7.7 - 1 17.7 - 1 3.7 - 3 9.7 7.2
Whiskers Creek NA FA-104 1 1.8 - 16 6.9 3.1 14 5.7 1.6 18 6.1 1.9 49 6.2 2.4
Total1 3 1.9 0.1 1 4.5 - 26 13.5 8.1 15 8.4 4.0 1 5.1 - 1 0.0 - 1.0 1.6 - 41 6.5 3.7 36 10.5 5.5 72 7.7 6.0 61 6.7 4.8 258 8.1 5.9
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Table 5.2-5. Mean (±SD) bankfull depth (m) of mesohabitats in Middle River tributaries.
Tributary Name Geomorphic Reach Focus Area Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 0.8 0.4 1 0.8 - 1 0.6 - 2 0.6 0.1 2 0.8 0.2 8 0.7 0.2
Unnamed 184.0 184.0-1 - 1 0.4 - 1 0.4 -
Fog Creek Fog-4 - 5 0.8 0.5 7 0.7 0.2 6 0.7 0.1 2 0.9 0.1 20 0.8 0.3
Fog Creek Fog-3 - 5 0.7 0.2 1 1.7 - 6 0.8 0.2 7 0.8 0.3 4 0.7 0.1 23 0.8 0.3
Fog Creek Fog-2 - 4 1.1 0.7 3 1.8 0.3 2 0.7 0.1 1 1.0 - 10 1.2 0.6
Fog Creek Fog-1 - 3 0.6 0.1 1 0.7 - 2 1.2 0.2 2 0.8 0.2 9 0.5 0.2 3 1.0 0.3 20 0.7 0.3
Unnamed 173.8 NA FA-173 3 0.5 0.2 3 0.8 0.1 3 0.7 0.3 9 0.7 0.2
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.4 - 1 0.5 - 1.0 0.7 - 5 0.6 0.2 6 0.7 0.4 14 0.6 0.3
Chinook Creek Chinook-1 - 5 1.0 0.5 5 0.6 0.4 2 0.7 0.1 12 0.8 0.4
Cheechako Creek Cheechako-1 - 1 0.7 - 4 1.1 0.1 1 1.3 - 4 1.1 0.4 3 1.3 0.3 13 1.1 0.3
Devils Canyon lower extent
Portage Creek NA FA-151 1 0.9 - 1 3.5 - 1 1.4 - 3 1.9 1.4
Unnamed 144.6 NA FA-144 1 0.8 - 1 0.8 -
Indian River NA FA-141 1 1.0 - 3 1.2 0.6 8 0.9 0.7 7 0.8 0.4 19 0.9 0.6
Gold Creek NA - 2 0.7 0.6 4 0.9 0.2 4 1.1 0.4 10 0.9 0.4
Fourth of July Creek NA - 2 0.7 0.1 1 0.5 - 2 0.5 0.2 2 0.8 0.2 7 0.6 0.2
Sherman Creek NA - 1 1.1 - 2 0.7 0.2 1 0.8 - 4 0.8 0.2
Skull Creek NA FA-128 1 1.1 - 1 0.9 - 1 0.4 - 3 0.8 0.3
Fifth of July Creek NA - 1 2.1 - 1 2.1 -
Deadhorse Creek NA - 1 0.4 - 1 0.4 - 2 0.4 0.0
Little Portage Creek NA - 1 1.7 - 1 1.7 -
McKenzie Creek NA - 1 0.7 - 1 0.6 - 2 0.7 0.1
Lane Creek NA - 1 1.0 - 1 1.0 -
Unnamed 115.4 NA FA-115 2 0.6 0.1 4 0.6 0.1 3 0.5 0.1 9 0.6 0.1
Gash Creek NA FA-113 1 0.5 - 1 0.5 -
Slash Creek NA FA-113 1 0.6 - 3 0.8 0.1 3 0.5 0.2 3 0.6 0.1 10 0.6 0.1
Unnamed 113.7 NA FA-113 1 0.9 - 1 0.9 -
Chase Creek NA - 1 0.7 - 1 0.8 - 2 0.8 0.0
Whiskers Creek NA FA-104 1 0.6 - 15 1.0 0.2 14 0.7 0.3 18 0.7 0.2 48 0.8 0.3
Total1 2 0.5 0.1 1 1.0 - 26 0.7 0.4 15 1.1 0.4 1 1.3 - 2 0.7 0.0 1.0 0.7 - 40 1.0 0.4 36 0.8 0.3 70 0.8 0.5 61 0.8 0.3 255 0.8 0.4
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Table 5.2-6. Mean (±SD) thalweg depth (m) of mesohabitats in Middle River tributaries.
Tributary Name Geomorphic Reach Focus Area Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 0.8 0.4 1 0.5 - 1 0.6 - 2 0.4 0.0 2 0.5 0.2 8 0.6 0.2
Unnamed 184.0 184.0-1 - 1 0.2 - 1 0.2 -
Fog Creek Fog-4 - 5 0.5 0.3 7 0.7 0.2 6 0.7 0.1 2 0.6 0.0 20 0.7 0.2
Fog Creek Fog-3 - 5 0.6 0.1 1 1.2 - 6 0.6 0.3 7 0.7 0.3 4 0.5 0.1 23 0.6 0.3
Fog Creek Fog-2 - 4 0.9 0.3 3 1.1 1.0 2 0.5 0.4 1 1.0 - 10 0.9 0.6
Fog Creek Fog-1 - 3 0.5 0.2 1 0.7 - 2 0.5 0.2 2 0.7 0.1 9 0.4 0.2 3 0.8 0.2 20 0.5 0.2
Unnamed 173.8 NA FA-173 3 0.5 0.2 3 0.4 0.0 3 0.4 0.2 9 0.4 0.1
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.2 - 1 0.5 - 1.0 0.7 - 5 0.6 0.2 6 0.5 0.2 14 0.5 0.2
Chinook Creek Chinook-1 - 5 0.6 0.3 5 0.5 0.3 2 0.3 0.1 12 0.5 0.3
Cheechako Creek Cheechako-1 - 1 0.7 - 4 0.9 0.1 1 1.1 - 4 0.6 0.3 3 0.7 0.2 13 0.8 0.2
Devils Canyon lower extent
Portage Creek NA FA-151 1 0.8 - 1 3.4 - 1 0.4 - 3 1.6 1.6
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 0.3 - 3 0.5 0.3 8 0.7 0.4 7 0.5 0.3 19 0.5 0.3
Gold Creek NA - 2 0.5 0.3 5 0.5 0.3 4 0.9 0.5 11 0.6 0.4
Fourth of July Creek NA - 2 0.4 0.2 1 0.5 - 2 0.4 0.1 2 0.5 0.0 7 0.5 0.1
Sherman Creek NA - 1 0.3 - 2 0.3 0.2 1 0.8 - 4 0.4 0.3
Skull Creek NA FA-128 1 0.5 - 1 0.9 - 1 0.2 - 3 0.5 0.3
Fifth of July Creek NA - 1 0.9 - 1 0.9 -
Deadhorse Creek NA - 1 0.2 - 1 0.4 - 2 0.3 0.1
Little Portage Creek NA - 1 0.9 - 1 0.9 -
McKenzie Creek NA - 1 0.6 - 1 0.6 -
Lane Creek NA - 1 1.0 - 1 1.0 -
Unnamed 115.4 NA FA-115 2 0.3 0.2 4 0.2 0.2 3 0.2 0.1 9 0.3 0.2
Gash Creek NA FA-113 1 0.5 - 1 0.5 -
Slash Creek NA FA-113 1 0.1 - 3 0.4 0.1 3 0.3 0.2 3 0.4 0.2 10 0.4 0.2
Unnamed 113.7 NA FA-113 1 0.2 - 1 0.2 -
Chase Creek NA - 1 0.2 - 1 0.2 - 1 0.8 - 3 0.4 0.3
Whiskers Creek NA FA-104 1 0.3 - 16 0.6 0.3 14 0.5 0.3 18 0.5 0.2 49 0.5 0.3
Total1 2 0.2 0.0 1 0.3 - 26 0.6 0.3 15 0.7 0.3 1 1.1 - 1 0.0 - 1.0 0.7 - 41 0.5 0.4 36 0.6 0.2 72 0.6 0.4 61 0.5 0.3 257 0.6 0.3
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Table 5.2-7. Mean (±SD) max pool and crest depths (m) of Beaver Pond and Pool mesohabitats in Middle River tributaries.
Tributary Name Geomorphic Reach Focus Area
Average Max Pool Depth Average Pool Crest Depth
Beaver Pond Pool All Units2 Pool All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 1 0.5 - 1 0.5 - 1 0.0 - 1 0.0 -
Unnamed 184.0 184.0-1 -
Fog Creek Fog-4 -
Fog Creek Fog-3 -
Fog Creek Fog-2 - 3 2.6 0.7 3 2.6 0.7 3 0.7 0.2 3 0.7 0.2
Fog Creek Fog-1 - 2 0.9 0.0 2 0.9 0.0 2 0.4 0.0 2 0.4 0.0
Unnamed 173.8 NA FA-173 3 0.6 0.1 3 0.6 0.1 3 0.2 0.0 3 0.2 0.0
Devils Canyon upper extent
Chinook Creek Chinook-2 -
Chinook Creek Chinook-1 -
Cheechako Creek Cheechako-1 - 4 1.7 0.3 4 1.7 0.3 4 0.5 0.1 4 0.5 0.1
Devils Canyon lower extent
Portage Creek NA FA-151
Unnamed 144.6 NA FA-144
Indian River NA FA-141 1 1.0 - 3 1.5 0.3 4 1.4 0.4 3 0.2 0.2 4 0.2 0.1
Gold Creek NA -
Fourth of July Creek NA - 2 1.0 0.0 2 1.0 0.0 2 0.3 0.0 2 0.3 0.0
Sherman Creek NA -
Skull Creek NA FA-128 1 0.7 - 1 0.7 - 1 0.1 - 1 0.1 -
Fifth of July Creek NA -
Deadhorse Creek NA -
Little Portage Creek NA -
McKenzie Creek NA -
Lane Creek NA -
Unnamed 115.4 NA FA-115 2 0.6 0.5 4 0.4 0.4 2 0.1 0.1 4 0.1 0.1
Gash Creek NA FA-113
Slash Creek NA FA-113 3 0.7 0.2 3 0.7 0.2 3 0.1 0.0 3 0.1 0.0
Unnamed 113.7 NA FA-113
Chase Creek NA - 1 1.5 - 1 1.5 - 1 0.1 - 1 0.1 -
Whiskers Creek NA FA-104 15 1.3 0.7 15 1.3 0.7 14 0.3 0.2 14 0.3 0.2
Total1 1 1.0 - 40 1.2 0.7 43 1.2 0.7 39 0.3 0.2 42 0.3 0.2
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Table 5.2-8. Mean (±SD) percent erosion along mesohabitat units in Middle River tributaries.
Tributary Name Geomorphic
Reach Focus Area Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 0.0 0.0 1 0.0 - 1.0 0.0 - 2 0.0 0.0 2 0.0 0.0 8 0.0 0.0
Unnamed 184.0 184.0-1 - 1 0.0 - 1 0.0 -
Fog Creek Fog-4 - 5 0.0 0.0 7.0 0.0 0.0 6 0.0 0.0 2 0.0 0.0 20 0.0 0.0
Fog Creek Fog-3 - 5 0.5 1.1 1 0.0 - 6.0 8.8 20.2 7 0.4 0.9 4 1.3 2.5 23 2.7 10.4
Fog Creek Fog-2 - 4 5.0 10.0 3 18.3 16.1 2.0 20.0 14.1 1 80.0 - 10 19.5 24.8
Fog Creek Fog-1 - 3 11.7 12.6 1 0.0 - 2 0.0 0.0 2.0 15.0 7.1 8 0.0 0.0 3 5.8 6.3 19 4.3 7.6
Unnamed 173.8 NA FA-173 3 31.7 30.6 3 66.7 28.9 3 35.0 56.3 9 44.4 38.9
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.0 - 1 0.0 - 1.0 0.0 - 5.0 0.0 0.0 6 3.3 8.2 14 1.4 5.3
Chinook Creek Chinook-1 - 5 0.0 0.0 5.0 0.0 0.0 2 0.0 0.0 12 0.0 0.0
Cheechako Creek Cheechako-1 - 1 0.0 - 4 0.0 0.0 1 0.0 - 4 0.6 1.3 3.0 0.0 0.0 13 0.2 0.7
Devils Canyon lower extent
Portage Creek NA FA-151 1.0 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 0.0 - 3 0.0 0.0 8 0.0 0.0 7 0.5 1.2 19 0.2 0.8
Gold Creek NA - 2.0 0.0 0.0 5 0.0 0.0 4 0.0 0.0 11 0.0 0.0
Fourth of July Cr. NA - 2 2.5 3.5 1.0 0.0 - 2 7.5 7.1 2 33.8 23.0 7 12.5 17.8
Sherman Cr. NA - 1 25.0 - 2 5.0 7.1 1 0.0 - 4 8.8 11.8
Skull Cr. NA FA-128 1 100.0 - 1 100.0 - 1 100.0 - 3 100.0 0.0
Fifth of July Cr. NA - 1 0.0 - 1 0.0 -
Deadhorse Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Little Portage Cr. NA - 1.0 0.0 - 1 0.0 -
McKenzie Creek NA - 1 2.5 - 1 50.0 - 2 26.3 33.6
Lane Creek NA - 1 0.0 - 1 0.0 -
Unnamed 115.4 NA FA-115 2 42.5 60.1 4 40.0 46.2 3 50.0 47.7 9 43.9 42.9
Gash Creek NA FA-113 1 0.0 - 1 0.0 -
Slash Creek NA FA-113 1 0.0 - 3 0.0 0.0 3 0.0 0.0 3 0.0 0.0 10 0.0 0.0
Unnamed 113.7 NA FA-113 1 0.0 - 1 0.0 -
Chase Creek NA - 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Whiskers Creek NA FA-104 1 0.0 - 16 4.9 7.7 14 1.8 4.6 18 3.0 4.6 49 3.2 5.8
Total1 2 0.0 0.0 1 0.0 - 26 5.9 14.3 15 1.7 6.5 1 0.0 - 2 1.3 1.8 1.0 0.0 - 41 12.8 26.6 36.0 3.4 10.1 71 7.7 23.3 61 6.8 19.6 257 7.0 19.9
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Table 5.2-9. Mean (±SD) percent undercut banks along mesohabitat units in Middle River tributaries.
Tributary Name Geomorphic
Reach Focus Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n
Mea
n SD
Tsusena Creek Tsusena-1 - 2 0.0 0.0 1.0 0.0 - 1.0 0.0 - 2 0.0 0.0 2 0.0 0.0 8 0.0 0.0
Unnamed 184.0 184.0-1 - 1 5.0 - 1 5.0 -
Fog Creek Fog-4 - 5 0.0 0.0 7.0 0.4 0.9 6 0.0 0.0 2 17.5 24.7 20 1.9 7.8
Fog Creek Fog-3 - 5 0.0 0.0 1 0.0 - 6.0 0.8 2.0 7 0.0 0.0 4 0.0 0.0 23 0.2 1.0
Fog Creek Fog-2 - 4 0.0 0.0 3.0 18.3 16.1 2.0 5.0 0.0 1 5.0 - 10 7.0 11.1
Fog Creek Fog-1 - 3 3.3 3.8 1 50.0 - 2.0 2.5 3.5 2.0 18.8 23.0 8 0.6 1.8 3 1.7 2.9 19 5.9 13.3
Unnamed 173.8 NA FA-173 3 1.7 2.9 3.0 8.3 14.4 3 0.3 0.6 9 3.4 8.2
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.0 - 1 0.0 - 1.0 0.0 - 5.0 1.0 2.2 6 0.0 0.0 14 0.4 1.3
Chinook Creek Chinook-1 - 5 0.0 0.0 5.0 0.0 0.0 2 0.0 0.0 12 0.0 0.0
Cheechako Creek Cheechako-1 - 1 0.0 - 4 0.0 0.0 1 0.0 - 4.0 0.0 0.0 3.0 0.0 0.0 13 0.0 0.0
Devils Canyon lower extent
Portage Creek NA FA-151 1.0 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 40.0 - 3.0 10.0 10.0 8 1.3 3.5 7 1.1 1.8 19 4.6 10.1
Gold Creek NA - 2.0 0.0 0.0 5 0.0 0.0 4 0.0 0.0 11 0.0 0.0
Fourth of July Cr. NA - 2.0 22.5 31.8 1.0 5.0 - 2 0.0 0.0 2 20.0 28.3 7 12.9 20.4
Sherman Cr. NA - 1 12.5 - 2 8.7 1.8 1 0.0 - 4 7.5 5.4
Skull Cr. NA FA-128 1.0 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Fifth of July Cr. NA - 1 0.0 - 1 0.0 -
Deadhorse Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Little Portage Cr. NA - 1.0 0.0 - 1 0.0 -
McKenzie Creek NA - 1 10.0 - 1 0.0 - 2 5.0 7.1
Lane Creek NA - 1 0.0 - 1 0.0 -
Unnamed 115.4 NA FA-115 2.0 0.0 0.0 4 5.0 10.0 3 0.0 0.0 9 2.2 6.7
Gash Creek NA FA-113 1 0.0 - 1 0.0 -
Slash Creek NA FA-113 1 0.0 - 3.0 0.0 0.0 3 8.3 14.4 3 0.0 0.0 10 2.5 7.9
Unnamed 113.7 NA FA-113 1 0.0 - 1 0.0 -
Chase Creek NA - 1.0 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Whiskers Creek NA FA-104 1 25.0 - 16.0 26.4 30.3 14 10.0 14.9 18 18.7 19.1 49 18.9 22.8
Total1 2 12.5 17.7 1 40.0 - 26 0.8 2.0 15 4.2 13.1 1 0.0 - 2 5.0 7.1 1.0 0.0 - 41.0 14.2 23.1 36.0 1.8 6.0 71 3.1 8.4 61 7.0 14.4 257 5.7 13.8
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Table 5.2-10. Mean (±SD) LWD count in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of LWD n Sum of
LWD
Tsusena Creek Tsusena-1 - 2 7 1 0 1 2 2 2 2 4 8 15
Unnamed 184.0 184.0-1 - 1 1 1 1
Fog Creek Fog-4 - 5 0 7 1 6 0 2 2 20 3
Fog Creek Fog-3 - 5 2 1 0 6 7 7 2 4 1 23 12
Fog Creek Fog-2 - 4 7 3 0 2 1 1 2 10 10
Fog Creek Fog-1 - 3 20 1 5 2 13 2 13 8 39 3 6 19 96
Unnamed 173.8 NA FA-173 3 83 3 9 3 27 9 119
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0 1 0 1 0 5 1 6 0 14 1
Chinook Creek Chinook-1 - 5 1 5 0 2 0 12 1
Cheechako Creek Cheechako-1 - 1 3 4 16 1 0 4 8 3 3 13 30
Devils Canyon lower extent
Portage Creek NA FA-151 1 2 1 2 1 0 3 4
Unnamed 144.6 NA FA-144 1 19 1 19
Indian River NA FA-141 1 12 1 15 3 47 7 44 7 108 19 226
Gold Creek NA - 2 11 5 21 4 3 11 35
Fourth of July Cr. NA - 2 7 1 7 2 6 2 3 7 23
Sherman Cr. NA - 1 1 2 6 1 1 4 8
Skull Cr. NA FA-128 1 0 1 0 1 0 3 0
Fifth of July Cr. NA - 1 0 1 0
Deadhorse Creek NA - 1 0 1 0 2 0
Little Portage Cr. NA - 1 0 1 0
McKenzie Creek NA - 1 4 1 3 2 7
Lane Creek NA - 1 1 1 1
Unnamed 115.4 NA FA-115 2 53 4 18 3 40 9 111
Gash Creek NA FA-113 1 5 1 5
Slash Creek NA FA-113 1 0 3 38 3 19 3 9 10 66
Unnamed 113.7 NA FA-113 1 1 1 1
Chase Creek NA - 1 4 1 0 1 15 3 19
Whiskers Creek NA FA-104 1 0 16 151 14 98 18 167 49 416
Total1 3 12 1 15 26 123 15 24 1 0 2 23 1 0 41 330 36 48 70 295 61 359 257 1,229
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Table 5.2-11. Mean (±SD) percent bedrock substrate in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mea
n SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 0.0 0.0 1 0.0 - 1 0.0 - 2 0.0 0.0 2 0.0 0.0 8 0.0 0.0
Unnamed 184.0 184.0-1 - 1 0.0 - 1 0.0 -
Fog Creek Fog-4 - 5 0.0 0.0 7 0.0 0.0 6 0.0 0.0 2 0.0 0.0 20 0.0 0.0
Fog Creek Fog-3 - 5 0.0 0.0 1 20.0 - 4 5.6 6.5 7 0.0 0.0 4 11.3 13.1 21 4.2 8.1
Fog Creek Fog-2 - 4 0.0 0.0 3 13.3 11.5 2 5.0 7.1 1 0.0 - 10 5.0 8.5
Fog Creek Fog-1 - 3 0.0 0.0 1 0.0 - 2 0.0 0.0 2 0.0 0.0 9 0.0 0.0 3 0.0 0.0 20 0.0 0.0
Unnamed 173.8 NA FA-173 3 0.0 0.0 3 0.0 0.0 3 0.0 0.0 9 0.0 0.0
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.0 - 1 0.0 - 1 0.0 - 5 0.0 0.0 6 0.0 0.0 14 0.0 0.0
Chinook Creek Chinook-1 - 5 0.0 0.0 5 0.0 0.0 2 0.0 0.0 12 0.0 0.0
Cheechako Creek Cheechako-1 - 1 0.0 - 4 1.3 2.5 1 40.0 - 4 10.0 20.0 3 8.3 14.4 13 8.5 15.6
Devils Canyon lower extent
Portage Creek NA FA-151 1 5.0 - 1 0.0 - 1 0.0 - 3 1.7 2.9
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 0.0 - 3 0.0 0.0 8 0.0 0.0 7 0.0 0.0 19 0.0 0.0
Gold Creek NA - 2 0.0 0.0 5 0.0 0.0 4 0.0 0.0 11 0.0 0.0
Fourth of July Cr. NA - 2 0.0 0.0 1 0.0 - 2 0.0 0.0 2 0.0 0.0 7 0.0 0.0
Sherman Cr. NA - 1 0.0 - 2 0.0 0.0 1 0.0 - 4 0.0 0.0
Skull Cr. NA FA-128 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Fifth of July Cr. NA - 1 0.0 - 1 0.0 -
Deadhorse Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Little Portage Cr. NA - 1 0.0 - 1 0.0 -
McKenzie Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Lane Creek NA - 1 0.0 - 1 0.0 -
Unnamed 115.4 NA FA-115 2 0.0 0.0 4 0.0 0.0 3 0.0 0.0 9 0.0 0.0
Gash Creek NA FA-113 1 0.0 - 1 0.0 -
Slash Creek NA FA-113 1 0.0 - 3 0.0 0.0 3 0.0 0.0 3 0.0 0.0 10 0.0 0.0
Unnamed 113.7 NA FA-113 1 0.0 - 1 0.0 -
Chase Creek NA - 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Whiskers Creek NA FA-104 1 0.0 - 16 0.0 0.0 13 0.0 0.0 18 0.0 0.0 48 0.0 0.0
Total1 2 0.0 0.0 1 0.0 - 26 0.0 0.0 15 1.7 5.2 1 40.0 - 2 0.0 0.0 1.0 0.0 - 41 2.0 7.5 34 1.8 5.2 71 0.0 0.0 61 0.7 4.1 255 1.0 4.9
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 83 October 2015
Table 5.2-12. Mean (±SD) percent boulder substrate in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation
Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 72.5 10.6 1 0.0 - 1 80.0 - 2 2.5 3.5 2 25.0 35.4 8 35.0 37.3
Unnamed 184.0 184.0-1 - 1 40.0 - 1 40.0 -
Fog Creek Fog-4 - 5 34.0 5.5 7 25.7 17.2 6 11.7 4.1 2 2.5 3.5 20 21.3 14.9
Fog Creek Fog-3 - 5 50.3 24.1 1 60.0 - 4 46.4 22.0 7 22.1 16.5 4 7.5 8.7 21 32.5 24.5
Fog Creek Fog-2 - 4 65.0 10.0 3 31.7 10.4 2 35.0 21.2 1 5.0 - 10 43.0 23.2
Fog Creek Fog-1 - 3 65.0 5.0 1 5.0 - 2 5.0 7.1 2 67.5 3.5 9 8.9 13.2 3 16.7 28.9 20 23.8 28.4
Unnamed 173.8 NA FA-173 3 33.3 5.8 3 23.3 20.8 3 23.9 10.5 9 26.9 13.0
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 10.0 - 1 30.0 - 1 10.0 - 5 34.0 16.7 6 13.3 8.2 14 21.4 15.1
Chinook Creek Chinook-1 - 5 68.0 16.4 5 64.0 8.9 2 35.0 7.1 12 60.8 16.8
Cheechako Creek Cheechako-1 - 1 70.0 - 4 77.5 15.0 1 25.0 - 4 51.3 36.1 3 66.7 5.8 13 62.3 25.1
Devils Canyon lower extent
Portage Creek NA FA-151 1 40.0 - 1 20.0 - 1 30.0 - 3 30.0 10.0
Unnamed 144.6 NA FA-144 1 11.1 - 1 11.1 -
Indian River NA FA-141 1 0.0 - 3 4.4 7.6 8 2.5 4.6 7 1.4 3.8 19 2.3 4.6
Gold Creek NA - 2 10.0 0.0 5 10.0 7.1 4 5.0 5.8 11 8.2 6.0
Fourth of July Cr. NA - 2 5.0 7.1 1 10.0 - 2 0.0 0.0 2 0.0 0.0 7 2.9 4.9
Sherman Cr. NA - 1 80.0 - 2 20.8 27.1 1 0.0 - 4 30.4 37.9
Skull Cr. NA FA-128 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Fifth of July Cr. NA - 1 55.6 - 1 55.6 -
Deadhorse Creek NA - 1 20.0 - 1 30.0 - 2 25.0 7.1
Little Portage Cr. NA - 1 0.0 - 1 0.0 -
McKenzie Creek NA - 1 20.0 - 1 5.0 - 2 12.5 10.6
Lane Creek NA - 1 0.0 - 1 0.0 -
Unnamed 115.4 NA FA-115 2 4.1 5.8 4 12.5 25.0 3 0.0 0.0 9 6.5 16.5
Gash Creek NA FA-113 1 0.0 - 1 0.0 -
Slash Creek NA FA-113 1 0.0 - 3 0.0 0.0 3 0.0 0.0 3 0.0 0.0 10 0.0 0.0
Unnamed 113.7 NA FA-113 1 15.0 - 1 15.0 -
Chase Creek NA - 1 50.0 - 1 30.0 - 1 40.0 - 3 40.0 10.0
Whiskers Creek NA FA-104 1 0.0 - 16 0.0 0.0 13 0.0 0.0 18 0.0 0.0 48 0.0 0.0
Total1 2 5.0 7.1 1 0.0 - 26 49.3 19.4 15 57.7 29.6 1 25.0 - 2 15.6 6.3 1 10.0 - 41 11.3 21.2 34 41.5 24.2 71 8.5 12.7 61 6.8 13.1 255 20.1 25.4
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 84 October 2015
Table 5.2-13. Mean (±SD) percent cobble substrate in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation
Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 20.0 7.1 1 40.0 - 1 15.0 - 2 40.0 42.4 2 45.0 7.1 8 33.1 20.7
Unnamed 184.0 184.0-1 - 1 50.0 - 1 50.0 -
Fog Creek Fog-4 - 5 44.0 5.5 7 50.7 20.5 6 44.2 20.6 2 65.0 21.2 20 48.5 17.8
Fog Creek Fog-3 - 5 43.7 20.5 1 20.0 - 4 41.8 18.1 7 57.9 9.9 4 60.0 21.6 21 50.0 18.5
Fog Creek Fog-2 - 4 25.0 10.0 3 36.7 11.5 2 40.0 14.1 1 40.0 - 10 33.0 11.6
Fog Creek Fog-1 - 3 28.3 7.6 1 35.0 - 2 47.5 10.6 2 30.0 0.0 9 68.3 14.1 3 43.3 23.1 20 51.0 21.1
Unnamed 173.8 NA FA-173 3 33.3 5.8 3 36.7 11.5 3 39.8 9.7 9 36.6 8.5
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.0 - 1 30.0 - 1 10.0 - 5 52.0 16.4 6 46.7 12.1 14 41.4 20.3
Chinook Creek Chinook-1 - 5 20.0 12.2 5 22.0 4.5 2 55.0 7.1 12 26.7 15.6
Cheechako Creek Cheechako-1 - 1 20.0 - 4 13.8 4.8 1 25.0 - 4 17.5 9.6 3 15.0 8.7 13 16.5 7.2
Devils Canyon lower extent
Portage Creek NA FA-151 1 50.0 - 1 75.0 - 1 60.0 - 3 61.7 12.6
Unnamed 144.6 NA FA-144 1 77.8 - 1 77.8 -
Indian River NA FA-141 1 0.0 - 3 38.9 25.3 8 66.3 27.7 7 42.8 26.7 19 49.8 30.1
Gold Creek NA - 2 50.0 14.1 5 56.0 15.2 4 50.0 25.8 11 52.7 17.9
Fourth of July Cr. NA - 2 40.0 28.3 1 80.0 - 2 80.0 0.0 2 70.0 14.1 7 65.7 22.3
Sherman Cr. NA - 1 15.0 - 2 35.8 27.1 1 85.0 - 4 42.9 33.6
Skull Cr. NA FA-128 1 10.0 - 1 55.0 - 1 20.0 - 3 28.3 23.6
Fifth of July Cr. NA - 1 43.4 - 1 43.4 -
Deadhorse Creek NA - 1 60.0 - 1 60.0 - 2 60.0 0.0
Little Portage Cr. NA - 1 40.0 - 1 40.0 -
McKenzie Creek NA - 1 50.0 - 1 70.0 - 2 60.0 14.1
Lane Creek NA - 1 30.0 - 1 30.0 -
Unnamed 115.4 NA FA-115 2 0.0 0.0 4 0.0 0.0 3 0.0 0.0 9 0.0 0.0
Gash Creek NA FA-113 1 40.0 - 1 40.0 -
Slash Creek NA FA-113 1 0.0 - 3 0.0 0.0 3 8.3 14.4 3 3.3 2.9 10 3.5 7.8
Unnamed 113.7 NA FA-113 1 10.0 - 1 10.0 -
Chase Creek NA - 1 40.0 - 1 60.0 - 1 40.0 - 3 46.7 11.5
Whiskers Creek NA FA-104 1 0.0 - 16 16.8 15.4 13 21.5 19.1 18 24.0 21.1 48 20.4 18.6
Total1 2 0.0 0 1 0.0 - 26 35.5 14.4 15 18.6 12.2 1 25.0 - 2 63.9 19.6 1 10.0 - 41 22.9 18.9 34 40.1 19.8 71 45.1 27.4 61 38.1 25.9 255 36.1 24.5
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 85 October 2015
Table 5.2-14. Mean (±SD) percent gravel substrate in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 5.0 0.0 1 40.0 - 1 5.0 - 2 55.0 49.5 2 17.5 17.7 8 25.0 29.5
Unnamed 184.0 184.0-1 - 1 10.0 - 1 10.0 -
Fog Creek Fog-4 - 5 18.0 8.4 7 19.3 14.8 6 34.2 15.6 2 22.5 10.6 20 23.8 14.3
Fog Creek Fog-3 - 5 6.0 4.2 1 0.0 - 4 6.3 4.8 7 20.0 8.7 4 21.3 14.9 21 13.3 11.1
Fog Creek Fog-2 - 4 10.0 0.0 3 11.7 2.9 2 20.0 14.1 1 55.0 - 10 17.0 14.8
Fog Creek Fog-1 - 3 6.7 5.8 1 60.0 - 2 32.5 38.9 2 2.5 3.5 9 22.8 18.0 3 33.3 23.1 20 22.8 21.5
Unnamed 173.8 NA FA-173 3 33.3 5.8 3 36.7 15.3 3 33.0 6.0 9 34.3 8.9
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.0 - 1 20.0 - 1.0 10.0 - 5 14.0 5.5 6 30.0 17.9 14 20.0 15.2
Chinook Creek Chinook-1 - 5 12.0 4.5 5 14.0 8.9 2 10.0 0.0 12 12.5 6.2
Cheechako Creek Cheechako-1 - 1 10.0 - 4 7.5 9.6 1 10.0 - 4 20.0 14.7 3 10.0 10.0 13 12.3 11.1
Devils Canyon lower extent
Portage Creek NA FA-151 1 5.0 - 1 5.0 - 1 10.0 - 3 6.7 2.9
Unnamed 144.6 NA FA-144 1 11.1 - 1 11.1 -
Indian River NA FA-141 1 0.0 - 3 31.1 8.4 8 30.0 26.2 7 39.4 20.9 19 32.0 22.4
Gold Creek NA - 2 35.0 7.1 5 30.0 12.2 4 40.0 24.5 11 34.5 16.3
Fourth of July Cr. NA - 2 35.0 35.4 1 10.0 - 2 10.0 0.0 2 17.5 10.6 7 19.3 18.8
Sherman Cr. NA - 1 5.0 - 2 40.2 49.7 1 15.0 - 4 25.1 33.8
Skull Cr. NA FA-128 1 20.0 - 1 45.0 - 1 70.0 - 3 45.0 25.0
Fifth of July Cr. NA - 1 0.9 - 1 0.9 -
Deadhorse Creek NA - 1 20.0 - 1 10.0 - 2 15.0 7.1
Little Portage Cr. NA - 1 60.0 - 1 60.0 -
McKenzie Creek NA - 1 30.0 - 1 20.0 - 2 25.0 7.1
Lane Creek NA - 1 60.0 - 1 60.0 -
Unnamed 115.4 NA FA-115 2 0.0 0.0 4 7.5 15.0 3 0.0 0.0 9 3.3 10.0
Gash Creek NA FA-113 1 45.0 - 1 45.0 -
Slash Creek NA FA-113 1 70.0 - 3 65.0 5.0 3 70.0 10.0 3 36.7 32.5 10 58.5 22.2
Unnamed 113.7 NA FA-113 1 75.0 - 1 75.0 -
Chase Creek NA - 1 10.0 - 1 10.0 - 1 20.0 - 3 13.3 5.8
Whiskers Creek NA FA-104 1 0.0 - 16 26.9 23.6 13.0 70.0 20.0 18 53.0 27.5 48 47.8 30.0
Total1 2 0.0 0.0 1 0.0 - 26 13.5 10.0 15 20.1 25.9 1 10.0 - 2 20.6 13.4 1 10.0 - 41 28.0 22.4 34 15.4 13.7 71 37.2 27.0 61 34.8 25.7 255 28.0 24.5
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 86 October 2015
Table 5.2-15. Mean (±SD) percent and and silt substrate in mesohabitat units of Middle r River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 2.5 3.5 1 20.0 - 1 0.0 - 2 2.5 3.5 2 12.5 10.6 8 6.9 8.4
Unnamed 184.0 184.0-1 - 1 0.0 - 1 0.0 -
Fog Creek Fog-4 - 5 4.0 5.5 7 4.3 5.3 6 10.0 6.3 2 10.0 14.1 20 6.5 6.7
Fog Creek Fog-3 - 5 0.0 0.0 1 0.0 - 4 0.0 0.0 7 0.0 0.0 4 0.0 0.0 21 0.0 0.0
Fog Creek Fog-2 - 4 0.0 0.0 3 6.7 11.5 2 0.0 0.0 1 0.0 - 10 2.0 6.3
Fog Creek Fog-1 - 3 0.0 0.0 1 0.0 - 2 15.0 21.2 2 0.0 0.0 9 0.0 0.0 3 6.7 5.8 20 2.5 7.2
Unnamed 173.8 NA FA-173 3 0.0 0.0 3 3.3 5.8 3 3.2 5.6 9 2.2 4.3
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 90.0 - 1 20.0 - 1.0 70.0 - 5 0.0 0.0 6 10.0 15.5 14 17.1 29.2
Chinook Creek Chinook-1 - 5 0.0 0.0 5 0.0 0.0 2 0.0 0.0 12 0.0 0.0
Cheechako Creek Cheechako-1 - 1 0.0 - 4 0.0 0.0 1 0.0 - 4 1.3 2.5 3 0.0 0.0 13 0.4 1.4
Devils Canyon lower extent
Portage Creek NA FA-151 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 100.0 - 3 25.6 29.8 8 1.3 3.5 7 16.4 13.7 19 15.9 25.9
Gold Creek NA - 2 5.0 7.1 5 4.0 5.5 4 5.0 5.8 11 4.5 5.2
Fourth of July Cr. NA - 2 20.0 0.0 1 0.0 - 2 10.0 0.0 2 12.5 3.5 7 12.1 7.0
Sherman Cr. NA - 1 0.0 - 2 2.4 3.4 1 0.0 - 4 1.2 2.4
Skull Cr. NA FA-128 1 60.0 - 1 0.0 - 1 10.0 - 3 23.3 32.1
Fifth of July Cr. NA - 1 0.0 - 1 0.0 -
Deadhorse Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Little Portage Cr. NA - 1 0.0 - 1 0.0 -
McKenzie Creek NA - 1 0.0 - 1 5.0 - 2 2.5 3.5
Lane Creek NA - 1 10.0 - 1 10.0 -
Unnamed 115.4 NA FA-115 2 77.6 3.4 4 57.5 9.6 3 80.0 26.5 9 69.5 18.5
Gash Creek NA FA-113 1 15.0 - 1 15.0 -
Slash Creek NA FA-113 1 0.0 - 3 20.0 17.3 3 20.0 10.0 3 51.7 37.5 10 27.5 26.8
Unnamed 113.7 NA FA-113 1 0.0 - 1 0.0 -
Chase Creek NA - 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Whiskers Creek NA FA-104 1 90.0 - 16 45.7 26.3 13 8.5 8.0 18 21.9 22.6 48 27.6 27.0
Total1 2 90.0 0.0 1 100.0 - 26 1.7 4.7 15 0.0 0.0 1 0.0 - 2 0.0 0.0 1.0 70.0 - 41 29.5 28.3 34 1.2 3.3 71 7.9 14.1 61 17.8 24.5 255 12.9 22.7
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 87 October 2015
Table 5.2-16. Mean (±SD) percent organic substrate in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Alcove Beaver Pond Boulder Riffle Cascade Chute Dry Percolation Channel Pool Rapid Riffle Run/Glide All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 2 0.0 0.0 1 0.0 - 1 0.0 - 2 0.0 0.0 2 0.0 0.0 8 0.0 0.0
Unnamed 184.0 184.0-1 - 1 0.0 - 1 0.0 -
Fog Creek Fog-4 - 5 0.0 0.0 7 0.0 0.0 6 0.0 0.0 2 0.0 0.0 20 0.0 0.0
Fog Creek Fog-3 - 5 0.0 0.0 1 0.0 - 4 0.0 0.0 7 0.0 0.0 4 0.0 0.0 21 0.0 0.0
Fog Creek Fog-2 - 4 0.0 0.0 3 0.0 0.0 2 0.0 0.0 1 0.0 - 10 0.0 0.0
Fog Creek Fog-1 - 3 0.0 0.0 1 0.0 - 2 0.0 0.0 2 0.0 0.0 9 0.0 0.0 3 0.0 0.0 20 0.0 0.0
Unnamed 173.8 NA FA-173 3 0.0 0.0 3 0.0 0.0 3 0.0 0.0 9 0.0 0.0
Devils Canyon upper extent
Chinook Creek Chinook-2 - 1 0.0 - 1 0.0 - 1.0 0.0 - 5 0.0 0.0 6 0.0 0.0 14 0.0 0.0
Chinook Creek Chinook-1 - 5 0.0 0.0 5 0.0 0.0 2 0.0 0.0 12 0.0 0.0
Cheechako Creek Cheechako-1 - 1 0.0 - 4 0.0 0.0 1 0.0 - 4 0.0 0.0 3 0.0 0.0 13 0.0 0.0
Devils Canyon lower extent
Portage Creek NA FA-151 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Unnamed 144.6 NA FA-144 1 0.0 - 1 0.0 -
Indian River NA FA-141 1 0.0 - 3 0.0 0.0 8 0.0 0.0 7 0.0 0.0 19 0.0 0.0
Gold Creek NA - 2 0.0 0.0 5 0.0 0.0 4 0.0 0.0 11 0.0 0.0
Fourth of July Cr. NA - 2 0.0 0.0 1 0.0 - 2 0.0 0.0 2 0.0 0.0 7 0.0 0.0
Sherman Cr. NA - 1 0.0 - 2 0.8 1.2 1 0.0 - 4 0.4 0.8
Skull Cr. NA FA-128 1 10.0 - 1 0.0 - 1 0.0 - 3 3.3 5.8
Fifth of July Cr. NA - 1 0.0 - 1 0.0 -
Deadhorse Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Little Portage Cr. NA - 1 0.0 - 1 0.0 -
McKenzie Creek NA - 1 0.0 - 1 0.0 - 2 0.0 0.0
Lane Creek NA - 1 0.0 - 1 0.0 -
Unnamed 115.4 NA FA-115 2 18.3 2.5 4 22.5 26.3 3 20.0 26.5 9 20.7 20.9
Gash Creek NA FA-113 1 0.0 - 1 0.0 -
Slash Creek NA FA-113 1 30.0 - 3 15.0 13.2 3 1.7 2.9 3 8.3 7.6 10 10.5 11.4
Unnamed 113.7 NA FA-113 1 0.0 - 1 0.0 -
Chase Creek NA - 1 0.0 - 1 0.0 - 1 0.0 - 3 0.0 0.0
Whiskers Creek NA FA-104 1 10.0 - 16 10.6 17.7 13 0.0 0.0 18 1.1 3.2 48 4.2 11.3
Total1 2 5.0 7.1 1 0.0 - 26 0.0 0.0 15 2.0 7.7 1 0.0 - 2 0.0 0.0 1.0 0.0 - 41 6.4 12.9 34 0.0 0.0 71 1.4 7.6 61 1.7 7.0 255 2.0 7.8
STUDY COMPLETION REPORT CHARACTERIZATION AND MAPPING OF AQUATIC HABITATS (STUDY 9.9)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page 88 October 2015
Table 5.2-17. Mean (±SD) percent instream cover in mesohabitat units of Middle River tributaries.
Tributary Name Geomorphic
Reach
Focus
Area
Aquatic Vegetation Bedrock Boulder Cobble Depth Insufficient Cover Overhanging Vegetation Undercut Bank Woody Debris All Units2
n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD n Mean SD
Tsusena Creek Tsusena-1 - 3 23.3 10.4 1 0.0 - 3 31.7 17.6 1 70.0 - 8 29.4 22.3
Unnamed 184.0 184.0-1 - 1 60.0 - 1 60.0 -
Fog Creek Fog-4 - 16 21.3 7.4 2 30.0 0.0 1 10.0 - 1 35.0 - 20 22.3 8.2
Fog Creek Fog-3 - 1 30.0 - 17 13.9 11.1 3 10.0 5.0 1 10.0 - 22 13.9 10.6
Fog Creek Fog-2 - 5 27.0 24.4 4 40.0 14.1 1 10.0 - 10 30.5 20.6
Fog Creek Fog-1 - 6 27.5 19.9 1 30.0 - 1 50.0 - 3 0.0 0.0 7 20.0 20.4 18 21.4 20.3
Unnamed 173.8 NA FA-173 1 0.0 - 3 33.3 25.2 5 36.0 20.7 9 31.1 22.6
Devils Canyon upper extent
Chinook Creek Chinook-2 - 4 25.0 5.8 1 40.0 - 3 0.0 0.0 5 26.0 30.5 1 10.0 - 14 20.0 21.1
Chinook Creek Chinook-1 - 6 43.3 10.3 6 33.3 5.2 12 38.3 9.4
Cheechako Creek Cheechako-1 - 9 44.4 8.8 4 53.8 22.1 13 47.3 13.9
Devils Canyon lower extent
Portage Creek NA FA-151 2 2.5 3.5 1 5.0 - 3 3.3 2.9
Indian River NA FA-141 10 21.4 16.4 3 18.9 2.0 5 16.8 6.4 18 19.7 12.5
Gold Creek NA - 1 20.0 - 1 30.0 - 3 0.0 0.0 6 26.7 19.7 11 19.1 18.7
Fourth of July Cr. NA - 4 30.0 4.1 1 20.0 - 2 12.5 10.6 7 23.6 9.9
Sherman Cr. NA - 2 42.5 10.6 1 0.0 - 1 41.7 - 4 31.7 22.0
Skull Cr. NA FA-128 3 0.0 0.0 3 0.0 0.0
Fifth of July Cr. NA - 1 25.6 - 1 25.6 -
Deadhorse Creek NA - 1 30.0 - 1 60.0 - 2 45.0 21.2
Little Portage Cr. NA - 1 20.0 - 1 20.0 -
McKenzie Creek NA - 1 70.0 - 1 70.0 -
Lane Creek NA - 1 10.0 - 1 10.0 -
Unnamed 115.4 NA FA-115 3 87.7 10.8 1 30.0 - 5 72.0 33.5 9 72.6 30.0
Gash Creek NA FA-113 1 15.0 - 1 15.0 -
Slash Creek NA FA-113 2 0.0 0.0 4 97.5 5.0 1 50.0 - 3 35.0 27.8 10 54.5 42.3
Unnamed 113.7 NA FA-113 1 15.0 - 1 15.0 -
Chase Creek NA - 1 80.0 - 1 80.0 - 1 0.0 - 3 53.3 46.2
Whiskers Creek NA FA-104 12 52.5 32.8 3 36.7 15.3 3 73.3 5.8 3 0.0 0.0 17 18.4 8.5 7 44.3 34.1 4 25.0 12.9 49 34.3 28.3
Total1 16 60.8 32.1 3 11.7 16.1 76 26.1 16.0 13 28.8 16.0 14 52.5 22.6 21 0.0 0.0 69 32.1 27.0 13 36.3 27.1 27 27.2 19.3 252 29.9 25.0
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Table 5.2-18. Sum of length (m) surveyed and composition by length of riparian cover types along Middle River tributaries.
Tributary Name Geomorphic
Reach Focus Area
Broadleaf Forest Closed Broadleaf Forest Open Conifer Forest Closed Conifer Forest Open None Nonforest Herbaceous Other Nonforest Shrub Alder Nonforest Shrub Other Nonforest Shrub Willow All Units2
n Length (m) & Percent n Length (m) & Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length (m) &
Percent n Length
Tsusena Creek Tsusena-1 - 2 163 24% 3 227 34% 1 28 4% 2 253 38% 8 671
Unnamed 184.0 184.0-1 - 1 16 100% 1 16
Fog Creek Fog-4 - 4 190 15% 1 25 2% 14 625 48% 1 457 35% 20 1,297
Fog Creek Fog-3 - 6 421 22% 6 743 39% 11 726 38% 23 1,889
Fog Creek Fog-2 - 9 440 64% 1 252 36% 10 692
Fog Creek Fog-1 - 1 19 1% 4 549 43% 13 646 50% 1 73 6% 19 1,287
Unnamed 173.8 NA FA-173 9 1,037 100% 9 1,037
Devils Canyon upper extent
Chinook Creek Chinook-2 - 3 151 31% 3 249 50% 8 94 19% 14 494
Chinook Creek Chinook-1 - 7 228 40% 5 336 60% 12 564
Cheechako Creek Cheechako-1 - 6 320 48% 7 353 52% 13 673
Devils Canyon lower extent
Portage Creek NA FA-151 3 295 100% 3 295
Unnamed 144.6 NA FA-144 1 84 100% 1 84
Indian River NA FA-141 14 609 71% 5 253 29% 19 862
Gold Creek NA - 4 99 21% 2 35 8% 2 212 46% 3 117 25% 11 463
Fourth of July Creek NA - 1 34 23% 5 100 66% 1 17 11% 7 151
Sherman Creek NA - 3 37 72% 1 14 28% 4 52
Skull Creek NA FA-128 1 23 35% 2 43 65% 3 66
Fifth of July Creek NA - 1 27 100% 1 27
Deadhorse Creek NA - 2 14 100% 2 14
Little Portage Creek NA - 1 24 100% 1 24
McKenzie Creek NA - 1 21 55% 1 17 45% 2 37
Lane Creek NA - 1 70 100% 1 70
Unnamed 115.4 NA FA-115 6 460 98% 3 10 2% 9 469
Gash Creek NA FA-113 1 26 100% 1 26
Slash Creek NA FA-113 4 32 18% 1 17 9% 5 129 73% 10 178
Unnamed 113.7 NA FA-113 1 17 100% 1 17
Chase Creek NA - 3 274 100% 3 274
Whiskers Creek NA FA-104 48 1,866 100% 1 2 0.11% 49 1,868
Total1 11 386 3% 32 1,677 12% 6 743 5% 19 1,517 11% 4 99 1% 63 2,811 21% 68 2,985 22% 11 1,249 9% 43 2,130 16% 257 13,596
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10. FIGURES
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Figure 3-1. Aquatic habitat characterization and mapping study area.
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Susitna River flows during field surveys
cfs measured at USGS gage #15292000 (Gold Creek)0
10000
20000
30000
40000
50000
2013 flows
2014 flows
July August September October
2013 field duration
2014 field duration
Figure 4.1-1 Susitna River flows in 2013 and 2014 with the timing of field surveys superimposed.
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Figure 4.1-2. Map of Upper River tributaries with tributaries selected for field-surveys identified.
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Figure 4.2-1 Map of Upper River lakes within the potential zone of reservoir inundation.
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Figure 5.1-1. Upper River tributary mesohabitat frequencies from 2012 videographic surveys.
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Figure 5.1-2. Upper River tributary mesohabitat frequencies from 2013-2014 ground surveys.
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Figure 5.1-3. 2014 dissolved oxygen profiles in Lakes 1-12.
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Figure 5.1-4. 2014 temperature profiles in Lakes 1-12.
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Figure 4.4-1 Aerial video capture of the Lower Susitna River mainstem showing highly complex braided
channels characteristic of main channel habitats in this river section.
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APPENDIX A: REMOTE LINE MAPPING 2012-2014
[See separate file for Appendix.]
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APPENDIX B: GROUND SURVEYS, 2013-2014
[See separate file for Appendix.]