HomeMy WebLinkAboutAPA4039I
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TK
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no.4039
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REASSESSMENT REPOR T
ON
UPPER SUSITNA RIVER
HYDROELECTRIC DEVELOPMENT
FOR
THE STA TE OF ALASKA
September 1974
HENRY J.KAISER COMPAN Y
'AkLlS
lA.lasm'ltelsdilrces',
Library'&Information Service,s
Anchorage,Alaska
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Section
TABLE OF CONTENTS
Page No.
LIST OF FIGURES
LIST OF TAB LES
ACIs:NOWLEDGMENTS_
A.Reassessment and Alternate Concept II-I
B.Electrical Load Growth Forecasts and System II-2
Balance
G.Hydroelectric Power Capacity of Susitna I II-3
D.Conceptual Engineering Studies II-4
E.Principal Proj ect Featur es II-4
//F.Estimated Susitna I Project Cost II-S
/G.Financial Evaluation and Economic Analysis II-S
H.Conclusion and Recommendations II-6
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II
III
INTRODUCTION
A.General
B.The Devil Canyon Proj ect
C.An Alternative Concept to Devil Canyon Project
SUMMARY AND CONCLUSIONS
POWER AND ENERGY FORECASTS
A.Methodology
B.Service Region
C.Population and Employment Forecasts
D.Energy Consumption Forecasts
E.Generation and Peak Loads
F.Power System Balance
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II-I
III-l
llI-l
III-l
III-3
III-IO
III-I?
III-19
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Section
IV
V
VI
VII
VIII
IX
TABLE OF CONTENTS (Cont)
HYDROLOGY
A.Study Information
B.Past Studies
C.Updated Studies at Gold Creek
D.Runoff at Proposed Damsite
E.Impact of New Data
F.Long Range Hydrologic Studies
TOPOGRAPHY AND GEOLOGY
A.Introduction
B.Topography
C.General Geology
D.Engineering Geology
POWER STUDIES
A.Introduction
B.Operation Studies
C.Comparison with the U.S.B.R.Devil Canyon
Project
CONCEPTUAL PROJECT STUDIES
A.Introduction
B.Selected Proj ect Concept
COST ESTIMA TE AND CONSTRUCTION PLAN
A.Summary
B.Construction Plan
C.Construction Schedule
FINANCIAL EVALUATION AND ECONOMIC
ANALYSIS
A.Introduction
B.Financial Evaluation
C.Economic Analysis·
Page No.
tv -1
IV -1
IV -1
IV -2
IV -2
IV -3
IV-6
V-I
V-I
V-I
V-I
V-3
VI-l
VI-l
VI-2
VI-3
VII-l
VII-l
VII-I
VIII-l
VIII-l
VIII-l
VIII-4
IX-I
IX-l
IX-l
IX-5
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Section
X
XI
XII
TABLE OF CONTENTS (Cont)
ENERGY INTENSIVE INDUSTRIES
ENVIRONM ENTA L CON SIDERA TIONS
A.Introduction
B.'Canyon Section of the River
C.Denali and Vee
D.The Transmission Systems
E.Summary
FUTURE DEVELOPMENT
A.Introduction
B.Downstream Development:Susitna II
C.Upstream Development:Susitna III
D.The Ultimate Development
E.Comparison with the U.S.B.R.Scheme
Page No.
X-I
XI-l
XI-l
XI-I
XI-2
XI-2
XI-2
XII-I
XII-l
XIl-l
XII-2
XII-2
XII-,3
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APPENDIX
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LIST OF,FIGURES
Figures are placed at the end of the section.
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Figure Noo
II-I
IV -1
IV -2
Power System Balance,Anchorage -
Cook Inlet and Fairbanks Areas,
1968 -1990
Coefficients Relating Susitna River Runoff
at Gold Creek to Runoff at Site B
Probability Distribution of Annual Discharge
at the Proposed Damsite B on Susitna River
Based on Runoff Records for Gold Creek
Station and Cantwe 11 Station
Section
II
IV
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VI-l
p..."",
VII-I
,.,.,...VII-2
VII-3-
VIII-l
Reservoir Operation and Power Generation VI
Data
Site Location Plan VII
General Layout VII
Sections V II
Tentative Construction Schedule VIII
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Table No.
III-l
III-2
III-3
III-4
III-5
III-6
1II-7
III-8
III,.9
III-iO
IV -1
IV-2
LIST OF TABLES
Forecasts of AlaskaLs Total Population
Alaskan Civilian Employment Forecasts,
1975 and 1980
Record and Forecast of Total Population and
Civilian Employment,Southcentral and
Interior Regions,1961-1990
Energy Sales to Residential-Commercial
Customer s in the Anchorage-Cook Inlet Area,
1961-1973
Energy Sales to Residential-Commercial
Customers in the Fairbanks Area,1961-1973
Record and Forecast of Total Energy Sales,
Anchorage-Cook Inlet and Fairbanks Areas,
1961-1990
Energy Sales,Net Energy for System,and
Peak Load,Anchorage-Cook Inlet and Fair-
banks Areas,1968-1990
Power System Balance,Anchorage-Cook
Inlet and Fairbanks Area,1968-1990
Projected Installation of New Generating
Capacity,Anchorage-Cook Inlet and Fairbanks
Areas
Capacity and Sales Proj ection
Probabilities of Annual Discharge at the Pro-
posed Damsite on the Susitna River
Frequency of Occurrence
Page No.
III-4
III-5
1II-8
1II-15
1II-16
III-18
1II-20
III-21
1II-22
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LIST OF TABLES (Cont)
Table No.Page No.
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VI-2
VIII-1
IX-1
IX-2
IX-3
IX-4
IX-S
IX-6
Summary of Thermal Load Factor sUnder
Normal and Dry Year Conditions
Annual Summary,Reservoir and Power
Operation
Summary of Capital Cost Estimate
Pro Forma Income Statement and Sources
and Applications of Funds
Summary of Fixed and Variable Annual
Charges
Computation of Cost to Power and Allocation
by Service Area
Cost of Gas Turbine Power,Early 1980s
Cost of Coal-Fired Steam Power with Gas
Turbine Peaking,Early 1980s
Comparison of Project Costs,Susitna I v.
Devil Canyon
VI-4
VI-S
VIII-2
IX-2
IX-6
IX-7
IX-12
IX-13
IX-IS
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APP ENDIX TAB LES
Records and Forecasts of Anchorage-Cook Inlet and Fairbanks
Area Utilities,1968-1990
2,Alaska Power Administration,"Utility Load Estimate Extended
to 1990 11
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4
Alaska Power Administration,"Statewide and Regional Utility
Load Estimates,1972-2000"
Stream Flow Summary,Susitna River,Gold Creek
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5 Stream Flow Summary,Susitna River,Cantwell
6 Stream Flow Summary,Susitna River,Damsite B
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ACKNOWLEDGMENTS
In preparing this report,the Henry J.Kaiser Company proj-
ect team has been given invaluable as sistance by the staff of
the Office of the Governor,the Departments of Economic De-
velopment,Labor and Natural Resources,as well as the
electrical utilities and municipal agencies of the Anchorage-
Cook Inlet and Fairbanks Areas.The Federal Power Com-
mission,Alaska Power Administration,and the Alaska Dis-
trict of the U.S.Army Corps of Engineers,and the Alaska
Chapter,Associated General Contractors of AmeriCa,Inc.
have also generously extended their cooperation.In addition,
many private firms and individual Alaskans were interviewed
in the course of this study.The Henry J.Kaiser Company
would like to express sincere gratitude for this support.
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1.INTRODUCTION-
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A.GENERAL
The hydroelectric developITlent potential of the upper Susitna River
has long been recognized.Investigation of the river was begun by
the U.S.Bureau of ReclaITlation (U.S.B.R.)in 1950,and by 1953
an ultim.ate developm.ent plan was form.ulated.The initial proposed
developITlent recom.m.ended by these and subsequent studies was the
Devil Canyon Project.The U.S.B.R.feasibility report for this
project was com.pleted in May 1960 and endor sed by the State of
Alaska in June of 196 L The Alaska Power AdITlinistrat.ion "Devil
Canyon Status Report "of May 1974 contained minor modifications to
the original de signs arid presented a cost estimate updated to
January 1974.
B.THE DEVIL CANYON PROJECT
The Devil Canyon Project report proposed construction of a concrete
arch dalTI in Devil Canyon and a low earth-rockfill darn at Denali as
the first step in the Susitna River I s development.A power plant was
proposed for the Devil Canyon sit~only because heavy drawdown of
Denali reservoir would make power generation there uneconomical.
T he project IS transmis sion system would supply electr icity to sub-
stations in Anchorage,Fairbanks,and the proposed site of the new
state capitol.
A s visualized by U.S.B.R.,the ultimate development of the upper
Susitna River would also include dams and power installations at
Watana and Vee Canyon at some later date.Further detailed studies
were recommended by U.S.B.R.to confirm the econoITlic feasibility
of the ultilTIate developlTIent plan indicated.
C.AN ALTERNATIVE CONCEPT TO DEVIL CANYON PROJECT
In 1973,the Henry J.Kaiser Company prepared a preliminary anal-
ysis of the hydroelectric development potential of the upper Susitna
River.At that tiITle it was considered that growth of regional power
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markets and rlsmg cost of fossil fuels could now make it feasible
to begin the long-delayed hydroelectric development of the river.
It was also anticipated that if the river were capable of producing
sufficiently economical power,a major energy-intensive industry
could be attracted to utilize any long-term surplus.
Following evaluation of the Devil Canyon Project as planned by
U.S.B.R.,the Henry J.Kaiser Company outlined an alternate and
potentially more e~onomical development concept.
This alternate concept visualizes a single dam and powerhouse in-
stallation near Devil Canyon in lieu of the two-dani,single power-
house scheme recommended by the U.S.B.R.This concept would
eliminate,at least from the initial development,the Denali dam and
reservoir,which appear to present unresolved technical,economic,
and environmental problems.Early in 1974,this alternate concept
was presented to the State of Alaska,along with a proposal to under-
take a small preliminary study.The study,as proposed,was to in-
clude preparation of a conc eptual design,order of magnitude cost
estimate,and a preliminary feasibility report for an alternate
hydroelectric project on the upper Susitna River.
.On June 4,1974,the State of Alaska contracted with HenryJ.
Kaiser Company for performance of the services set forth intb.e
proposal.
This report presents the results of Kaiser l s study.In this study,
the project concept recommended by Kaiser for initial development
of the Susitna River is identifie.d as Susitna 1,Future projects to
utilize the ultimate.development potential of the river are identified
as Susitna II and Susitna III.
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II.SUMMARY AND CONCLUSIONS
A.REASSESSMENT AND ALTERNATEtCONCEPT,
This study has reassessed the U,S.Bureau of Reclama-tion (U,S.B.R,J
scheme for development of the hydroelectric potential of the upper
Susitna River and presents an alternate concept for it-s initial and
ultimate development.
The U.S.B.R.scheme consists of a concrete arch darn and a power
plant at Devil Canyon and an earth-rockfill darn at Denali as the fir st
step in the Susitna River 1 s development.Ultimate development would
include darns and power installaJions at Watanaand Vee Canyons.
These facilities would effect full regulation of the river and provide
a total instailed capacity of 1,372,000 kilowatts with firm annual
ener gy production of 7,000 million kilowatt-hour s.The installed
capacity of the Devil Canyon plant would be 600,000 kilowatts and
the firm annual energy production would be 2,900 million kilowatt-
hour s.-The construction cost for the fir st step,based on January
1974 prices was estimated to be $597,100,000.With $84,900,000
of interest during construction,the estimated total project invest-
ment cost was $682,000, 000.
The Kaiser concept includes three projects,designated Susitna I,II,
and III,which would be located as shown in Section ~II,Figure VII-I.
The initial project,Susitna I,which is the main focus of this report,
would consist of a hydroelectric development at a locat-ion about five
miles upstream from Devil Canyon.The power plant would have an
installed capacity of 700,000 kilowatts and a firm annual energy pro-
duction of 3,372 million kilowatt-hours.As in the Devil Canyon1s
sch:eme,the Susitna I project transmission system wot.1ld deliver
power to the Anchorage-Cook Inlet and Fairbanks Areas.Subse-
quent stage s of development would include Susitna II,a darn and -tun-
of-river power plant located below Portage Cr eek,with an in-
stalled capacity of 163,000 kilowatts and an annual energy produc-
tion of 785 million kilowatt-hours.Susitna III would consist of a
dam and power plant located approximately at the headwater limit
of the Susitna I reservoir.Susitna III would nave an installed
capacity of 445,000 kilowatts and an annual energy production of
1,840 mill ion kilowatt-hour s.
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The construction cost of Susitna I was estimated at $525,720,000
based on June 1,1974 price levels.Including interest during con-
struction of $77,000,000,the estimated total project investment
co sts would be $602,720,000.On the basis of the schedule shown
in Section VIII,Figur e VIII-I,with engineering starting in early
1975 and main constru ction starting in 1977,the estimated total
project investment costs would be $638,100,000,
The overall alterna te development cone ept would have a total in-
stalled capacity of 1,308,000 kilowatts and a total annual energy pro-
duction of 6,309 million kilowatt-hours.These totals are slightly
less than the figures presented for the U.S.B.R.development scheme,
and the reduction is directly attributed to avoiding development of the
Denali Reservoir which may have an unfavorable environmental
impact.
Economic comparisons of Susitna I with alternative thermal develop-
ment and.the Devil Canyon-Denali scheme indicate that Susitna I is
the most attractive alternative.
The findings of this report are summarized on the following pages.
B.ELECTRICAL LOAD GROWTH FORECASTS AND SYSTEM BALANCE
Load growth forecasts through 1990 have been prepared for major
Anchorage-Cook Inlet and Fairbanks Area utilities,resulting in the
following conclusions on the region 's energy consumption and peak
load.-Anchorage-Cook Inlet Fairbanks Total
Net Peak Net Peak Net Peak
Energy Load Energy Load Energy Load
Year million thousand million thousand million thousand
kwh kw kwh kw kwh kw
Actual-1968 559 125 161 43 720 168
1973 1,090 213 318 73 1,408 286
Forecast
1975 1,400 271 410 87 1,810 358
1980 2,740 513 803 164 3,543 677
1985 5,080 928 1,354 266 6,434 1,194
1990 9,420 1,721 2,281 434 11,701 2,155
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Existing system expansion plans for the Anchorage-Cook Inlet A rea
are capable of satisfying this forecast through mid-1979.Prior to
mid-1981,the earliest date at which Susitna I could be commissioned,
it would be neces sary to add approximately 84,000 kilowatts of new
capacity to serve this area.Existing expansion plans for the Fair-
banks Area should satisfy load growth require~ents until mid-1982.
The power system balance indicates that if Susitna I were commis-
sioned in mid-1981,its 700,000 kilowatt capacity would be fully ab-
sorbed by the systems normal load growth through early 1986.
Power and energy forecasts by area and the overall power system
balance a.re illustrated in Figure II-I.
C.HYDROELECTRIC POWER CAPACITY OF SUSITNA I
Hydrologic studies based on 23 years of recorded river flow at Gold
Creek indicated an estimated flow at the Susitna I site as follows:
Annual Flow in Acre-Feet
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Minimum
3,772,000
Average
6,639,000
Maximum
7,795,000
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The minimum annual flow was recorded in 1969 and was not taken into
account in the Alaska Power Administration 1 s "Devil Canyon Status
Report,II 1974.
Reservoir operation studies for the 23-year period of record and
hydrologic studies indicated that 3,372 million kilowatt-hours of
ener gy cOllldbe produced at lea st 97%of the time.
Because Susitna I will be part of alar ger system including sub stantial
thermal capacity,the system as a whole could be operated to meet
overall demand i~a dry year,such as 1969,despite a reduction in
Susitna I energy production.Accordingly,the project's firm annual
energy capability has been established at 3,372 million kilowatt-
hour s for an installed capacity of 700,000 kilowatts at 55%plant
fq.ctor.On the average,500 million kilowatt-hour s of secondary
energy can be produced per year.
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D.CONCEPTUAL ENGINEERING STUDIES
These studies used U.S ..GeologicaL.5urvey maps.to identify
sites potentially favorable for locations of dams and impoundment
of large reservoirs.River runoff records from the Up S.G.S.
Gold Creek and Cantwell stations,and clim.atological data from a
number of weather stations in the region were used to assess the
water resource of the river.All of these data were combined to eva1u-
ate several alternate concepts of project scope and layout.The geo-
logic and engineering reconnaissance survey made early in the study
confirmed the superiority of the terrain of the selected site over
several alternate sites.It revealed the occurrence at the site of a
granitic-type bedrock eminently suitable for project location and use
in dam.construction,and identified important geologic features which
were significant in selecting the layout and location of main project
features.The reconnaissance also provided preliminary informa-
tion on the availability of other construction m.at.erials p
Estimates of cost were based on conceptual designs,site character-
istics,and most recent inform.ation on costs of labor,equipment,
and materials,all related to the project site.
E.PRINCIPAL PROJECT FEATURES
Type of dam
Crest elevation,feet (m.s.1.)
Crest length,feet
Height of dam,feet
Reservoir m.aximum normal
capacity,acre-feet
Reservoir area,acres
Power plant type
Installed capacity -kilowatts
Units
Average gross head,feet
Range in gros s head,feet
Annual plant factor,percent
Annual firm energy,kilowatt-hours
Annual average energy,
kilowatt-hour s
Transmis sion line,rating
kilovolts
Length to Anchorage,mile s
double circuit
Length to Fairbanks,mile s
single circuit
Concrete face rockiill
1,755
3,050
800 -approximately
5,760,000
24,200
Underground
700,000
4 @ 175,000 Kw,Francis type
702
758-518
55
3,372 million
3,872 million
230
139
214
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F.ESTIMATED SUSITNA I.PROJECT COST
The estimated construction and equipment costs for the project,
ba sed on June 1,1974 price level s,are summarized below:
Hydroelectric Plant
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Site access,reservoir clearing,
and diversion tunnels
Darn and spillway
Power plant and related facilities
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Living quarters and general property
Subtotal
T ransmi s s ion System
Total construction costs
Interest during construction
Total Estimated Project
Investment
$47,185,000
263,690,000
129,570,000
2,880,000
$443,325,000
82,395,000
$525,720,000
77,000,000
$602,720,000
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The above estimate includes contingency and engineering costs but
does not include escalation to the date of award of the construction
and equipment supply contracts.
G.FINANCIAL EVALUATION AND ECONOMIC ANALYSIS
A pro forma income statement has been prepared for Susitna I in
order to determine whether the project l s cost,construction
schedule,and revenue base are consistent with a practical financ-
ing plan.The results of this analysis indicate that the project would
be capable of making regular interest payments beginning in Janu-
ary 1982,six months after I3tartup,and that regu'lar sinking fund
installments could begin in the fourth quarter of 1985.
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The project would produce power valued at an average 14.5 mills
per kilowatt-hour at the service area step-down sub station.Allow-
ing for differences in load factor and especially the incremental
cost of transmission,SusitnaI power would cost 13.5 mills per
kilowatt-hour in Anchorage and 17.5 mills per kilowatt-hour in
Fairbanks.
For comparison with Susitna I costs,it is estimated that power gen-
erated by new thermal capacity commissioned in 1981 would be ap-
proximately 15.9 mills in the Anchorage-Cook Inlet Area,and approxi-
mately 18.6 -21.0 mills in the Fairbanks Area.It has also been
estimated that Susitna I power cost would be approximately 75%that
of the U.S.B o R.Devil Canyon project.
H.CONCLUSIONS AND RECOMMENDATIONS
The summary presented above indicates that the Susitna I project pro-
vide s an economical means of meeting the service area electrical
load growth requirements of the 19808 ..
The generation of fir st power in 1981 is contingent upon the comple-
tion early in 1976 of the definitive designs and cost estimates required
to firm-up project feasibility and provide a sound basis for project
financing measures.This requires that engineering be started early
in 1975 so that the prerequisite site mapping and detailed geologic in-
vestigations can be carried out as early as possible in 1975.
Application for preliminary licensing by the Federal Power Commission
should be made before the end of 1974.Environmental studies should
be started as early as possible so that environmental questions can
be resolved without causing delay to project implementation.
The key steps in the implementation of the project and generation of
first power in 1981 are as follows:
•Establishment of Power Authority_
It is recommended that the State of A laska establish an auto-
nomous development authority to undertake the Susitna Project.
Such an agency would have a s its immediate re sponsibility the
financing and management of this project;however,its role
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later could be expanded to include similar developments in
other parts of Alaska.
Initially,the operations of such an authority probably must be
funded by the state government.However,as the authority
develops into a revenue-producing ag~ncy,it is considered
desirable that it become fully self-sufficient.
Application for Preliminary Licensing by the Federal Power
Commission.
Environmental Studies.
Land Acquisition.
Most land in the upper Susitna Basin,particularly in the area of
Susitna I is both withdrawn as a Federal powersite and also ear-
marked for selection by native regional corporations under the
Alaska Native Claims Settlement Act (ANCSA).It is not clear
whether either of these designated uses establishes a peremptory
claim to use of the land.
It is considered that the State of Alaska may require Susitna Basin
lands either by arranging for assignment of the Federal powersite
withdrawal,or by negotiating for NACSA selection of eligible
lands,with subsequent lease or sale to the State or its power
authority.
•Engineering.
This will include the following main items:
Mapping of project site area
Detailed investigations of site geology including drilling and
investigation of construction materials
Development of definitive de signs
Preparation of definitive cost estimate and application for full
licensing by the Federal Power Commission
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Preparation of specifications and contracts for construction
and for supply and installation of m.ajor equipm.ent
Recom.m.endations for awards of construction and supply
contracts
Engineering and m.anagem.ent of construction
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SUs/rNA HYDROELECTRIC PROJECT
ANCHORAGE .COOK INLET AND FAm8ANKS AREAS
POWER SYSTEM BALANCE
1968 .1990
--.-----~~-~---+----.J
12,000
~
~
/0,000 ~
......
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~+--+--A---+-----l==1 r==l -~8,000 ~
~
~
6,000 fi.
............
4,000 ~
ANCHORAGE -COOK INLET ~
r-~NET ENERGY ~
,2000 ~
I
ANCHORAGE -COOK INLET $FAIRBANKS '
TOTAL NET ENERGY
+ACTUAL I +I FORECAST
I I
!
ANCHORAGE -COOK INLET
4 FAIRBANKS AREAS
GENERATING CAPACITY
ANCHORAGE-CODKINLET
$FAIRBANKS AREAS
I I I I "---+TOTAL PEAK LOAD
ANCHORAGE-COOK INLET
PEAK LOAD
o
/96B /969 1970 [971 1972 1973 1974 1975 1976 /977 1978 1979 /980 1981 1982 1983 1984 /985 1986 /987 1988 1989 /990
'*UNSCHEDULED CAPACITY ADDITIONS
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III.POWER AND EN ERGY FORECASTS
A.METHODOLOGY
The methodology used in forecasting Susitna 1 proj ect power and
energy demands is as follows:
• A primary service region was selected for the project.
•Population and employment of the service region were forecast
to 1990.
•Growth of regional utilities'electrical energy sales was forecast
based on its historical relationship with population and employ-
ment;nonutility industrial and U.S.military energy consumption
were also evaluated.
•Power system generation and peak loads were projected in terms
of recorded system operating parameters for regional utilities.
•Power and energy demands on Susitna I were projected in terms
of the regional demand-capacity balance in the 1980 s.
B.SERVICE REGION
The primary service region selected as a forecasting base for proj-
ect power sales consists of the U.S.Census Divisions of Anchorage,
Kenai-Cook Inlet,Matanuska-Susitna,and Seward--designated the
'1Anchorage-Cook Inlet Ar ea;II and Fairbanks--designated the II Fair-
banks Area.II
The criteria for this selection are as follows:
1.Service to Population
Based on the 1970 U.S.Census,and subsequent estimates by the
Sta te of Alaska Depa.rtment of Labor,the Anchorage-Cook Inlet
Area today comprises approximately 90%of the population of
Alaska l s South Central Region,one of the state's five major
geographical subdivisions,and it includes approximately 50%of
the population of the state as a whole.The Fairbanks Area com-
prises approximately 80%of the population of the Interior Region
and 15%of the state as a whole.
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Together,the Anchorage-Cook Inlet and Fairbanks Areas make
up 65%of Alaska's total population.Through 1990,it is antic-
ipated that the growth rates of these areas will be higher than
that of the state as a whole.
On the basis of this selected service region p it is believed that
the project can convey benefits to a sufficiently large and broadly
distributed population base to justify its sponsorship by the State
of Alaska.
2.Transmis sion Economy
The Susitna 1 project site is located approximately 139 transmis-
sionmiles north of the Anchorage-Cook Inlet Area and 214 trans-
mission miles south of Fairbanks.It is projected that transmis-
sion to both of these areas would follow the present routes of the
Anchorage-Fairbanks Highway,and!or of the Alaska Railroad.
Roughly 900/0 of the Anchorage-Cook Inlet Area population is lo-
cated adjacent to this main transmission route,while the remain-
ing 10%is interconnected by transmission systems of area utility
systems.Approximately 100%of Fairbanks Area population is
located adjacent to the terminus of the northern transmission sec-
tion.As a result,the 'extension of service to both of these areas
offers a reasonable concentration of electrical load in terms.of
the length of transmission required.
In addition to the Anchorage-Cook Inlet and Fairbanks Areas,a
small additional population is now located ip the Susitna-Chulitna
and Nenana valleys adjacent to the p'roposed transmission main-
line.It is expected that this population will increase rapidly due
to ease of access via the new Anchorage-Fairbanks Highway.The
propo s ed new location of the Alaska state capitol is also in this
area.Therefore,the practical service region of the project has
a substantial capability of expansion along its transmis sion
mainline.
Areas which have been excluded from the service region in this
report fall into two categories.The first of these includes re-
mote areas which,for the foreseeable future,are not expected to
have sufficient population and electrical load to make extended
transmission of Su sitna-generated power competitive with local
generation,even where the latter is very costly.The second
IlI-2
-
-
-
-
category includes two areas which now have small population
bases,but which could warrant extended transmission in the fu-
ture.The first of these areas is the middle Tanana valley,in-
cluding the community of Big Delta.It is probable that this area
will be connected by Fairbanks Area utilities prior to completion
of initial development of the Susitna River power,The second
area is the eastern perimeter of Prince William Sound,including
Valdez and Cordova.This is expected to be one of Alaska's
fastest growing population centers in the late 1970s and 1980s
due to the construction of the Alyeska Pipeline,the probable
construction of a natural gas pipeline from the North Slope,and
subsequent development of refining and petrochemical industries
at the pipeline termini.This area has been excluded from the
service region in this report for the following reasons.First,
serving it would require an additional transmission system nearly
as long as the mainline;this would add substantially to the deli-
vered cost of Susitna power in this area.Second,this area is
expected to have relatively inexpensive sources of fuel for local
power generation,which,due to transmission cost of Susitna
power,could easily be more competitive.Third,although this
areal s population should increase several times from its present
base,inclusion of the r elated electrical load in this report would
n'ot affect the economic feasibility of the initial Susitna project.
C.POPULATION AND EMPLOYMENT FORECASTS
1.Forecasting Guidelines
To forecast growth of population and employment in the Anchorage-
Cook Inlet and Fairbanks Areas through'1990,two sets of state-
wide and regional forecasts have been used.These were prepared
by the State of Alaska Department of Labor,Research and Anal-
ysis Section (ADL)and by the National Bank of Alaska,Economics
Department (NBA).Other population and employment forecasts
have also been consulted,particularly those prepared recently
for Alyeska Pipeline Service Company,Inc.,and the University
of Alaska,Institute of Social,Economic and Government Re-
search.In addition,reference has been made to forecasts cited
in the drafts of the Alaska Power Administration l s Alaska Power
Survey,1974.The ADL and NBA forecasts are summarized in
Tables III-1 and III-2.
III-3
_.
-
TABLE III-1
FORECASTS OF
ALASKA'S TOTAL POPULATION
.....
-
-
1974
1975
1976
1977
1978
1979
1980
Alaska Department
of Labor (ADL)
357,200
386,600
448,400
National Bank of
Alaska (NBA)
361,300
406,900
433,2.00
446,100
461,000
473,700
479,900
Sources:Annual Population and Employment Projections 1961-1980,
Alaska Department of Labor,Research and Analysis Section
National Bank of Alaska,Economics Department.
III-4....__..._..__.__-.J
-
-
TABLE III-2
ALASKA CIVILIAN EMPLOYMENT FORECASTS
1975 AND 1980
Alaska Department oL Labolr (ADL)Annual Rate
Industry 1975 1980 of Change
Construction 18,000 12,000 -5.9--Mining 3,000 6,400 16.3
Distributive
and Service 59,100 77,600 5.6
Government 46,400 56;900 4.2
Federal 17,500 IS,OOO • 6
State-Local 28,900 38,900 6.2
Manufacturing 10,500 13,500 13.2
Other 14,200 16,200 2.7
TOTALI 151,200 182,600 3.9
-
-
i .;0.;.;0..
National Bank of Alaska (NBA)Annual Rate
Industry 1975 1980 of Change
Construction 18,100 14,100 -4.1
Mining 3,000 5,500 12.9
Distributi ve
and Service 65,000 83,000 5.1
Government 49,900 62,500 4.6
Federal 17,400 17,900 . 6
State -Lo cal 32,500 44,600 6.5
Manufacturing 13,500 12,100 -2.0
Other 14,300 16,300 2.7
TOTAL 160,000 193,500 3.9
1Totals may not add due to rounding,
Source:See Table Ill-l.
III-5
.,...,-.....
\~
.-
-
-
~..
The ADL and NBA forecasts extend to 1980.Both forecasts have
been based on polynomial regression analysis of historical trends,
with estimates of the impacts of Alyeska Pipeline construction be-
ginning in 1974.Both forecasts anticipate sustained growth of
population and employment following the peak impacts of Alyeska
Pipeline's construction in the late 1970s.This growth will be
based on activity in mining p and other industrial sectors,as well
as public,commercial,and residential construction.In addition
to private sector growth,the NBA forecast has noted that the
State of Alaska"will receive net royalties and severance taxes of
as much as $900 million per year from first-stage North Slope oil
and gas production;these revenues are expected to stimulate in-
creased investment and employment in state and local government.
The ADL and NBA population forecasts differ principally with re-
spect to growth between mid-1974 and mid-197 5.During this
period,ADL forecasts an increase of 29,400 persons compared
to the NBA forecast of 45,600.Beyond this,for the period 1975
through 1980,ADL projects a population gain of 16.0%with an
annual compound growth rate of 3.0%.For the same period,the
NBA forecasts an overall population increase of 17.90/0,with a
corresponding annual growth rate of 3.3%.
Key differences between the ADL and NBA employment forecasts
are as follows:
(a)Compared to ADL,NBA forecasts that Alyeska Pipeline con-
struction will have greater impact on employment in distribu-
tion and services,.and in state government.
(b)NBA forecasts a smaller drop in construction activity in the
late 1970s than does ADL,with less strength in mining and
manufa c tu ring.
(c)NBA forecasts a larger total employment gain from 1975 to
1980 than does ADL.
Both forecasts indicate that approximately 90%of Alaska i s new
employment in the last half of the 1970s will be in the distributive
and service sectors,and in state government.
III-6
Kaiser's judgment is that both the ADL and NBA forecasts have
been conservative in their evaluation of industrial impacts on
Alaska's economy resulting from further development of the
petroleum industry in the late 1970s,particularly relating to gas
pipeline impact and development of the manufacturing sector.
Further p it has been impossible for the forecasters to consider
the magnitude of po s sible impacts from major expansion of the
oil indu stry in southern Cook Inlet,the Gulf of Alaska,and pos-
sibly other areas.Such developments are probable and will justi-
fy substantially greater forecasting optimism when their size can
be determined.
For this analysis p the higher NBA forecast has been selected as
the basis for estimates of population and employment growth
through 1980.In order to relate the NBA statewide forecast to
the Susitna project service region,Kaiser has estimated the
probable Southcentral and Interior regional components of this
forecast,based on ADL data.The result revises the NBAI s
statewide figures to a regional base consistent with the historical
distribution -r ecorded by ADL.
2.Forecasts to 1980 and 1990
The record of growth in Southcentral and Interior Alaska's popula-
tion and employment from 1961 through 1973 is indicated in Table
1II-3,along with forecasts to 1980 by ADL and by Kaiser based
on the NBA statewide data as noted above.
Kaiser's forecast to 1990 is also shown in Table III-3.In the
absence of authoritative guidelines,trends in population and em-
ployment to 1990 are based primarily on a statistical extrapolation
of the historical record from 1961 through 1973,and of the revised
NBA fotecast through 1980.The annual growth rates forecast for
the 1980s are somewhat less than those experienced in the past
decade and those expected in the remainder of the 1970s.This
reflects the substantially greater population and economic base to _
be achieved by 1980 and the associated probability that even very
large industrial development proj ects will have a smaller percent-
age impact on growth than the Alyeska Pipeline has at the present
time.Even with this limitation,the forecast annual volume of
growth is on the average substan~ially larger than for the years
prior to 1980.
1II-7
TABLE III-3
RECORD AND FORECAST OF
TOTAL POPULATION AND CIVILIAN EMPLOYMENT
SOUTHCENTRAL AND INTERIOR REGIONS
1961-1990
Southcentral Interior
Year Population Employment Population Employment
1961 115,900 35,400 48,100 12,300-,1962 119,100 36,600 49,850 12,950
1963 122,400 37,850 51,650 13,550
1964 123,800 40,300 50,700 13,850-1965 132,600 44,700 50,500 14,850
1966 136,550 46,700 50,850 15,100
1967 140,200 49,500 51,050 15,000
1968 146,100 50,950 50,950 15,400
1969 151,800 54,900 52,500 16,950
1970 164,900 59,100 56,500 17,600
.~1971 174,600 62,950 55,000 18,350
r""'"1972 183,000 66,800 56,400 1 9,100
1973 188,700 71,100 56,300 19,300-- - - - - - - - - - - - - - - - - - - ---- - - F ORECA ST -- - - - - --- - - - - --- - - - --- - - - -
1975 ADL 223,100 84,800 66,500 26,500
Kaiser 1 236,000 90,000 70,000 28,000
1980 ADL 265,000 104,000 70,000 28,000
Kaiser 1 284,000 111,000 75,000 30,000
1990 Kaiser 415,000 162,000 128,000 51,000
1 Based on NBA'statewide forecasts.
Sources:1961-1971,State of Alaska,Department of Economic Develop-
ment,Alaska Statistical Review,1972
1972-1973,State of Alaska,Department of Labor,Annual
Population and Employment Projections,1961-1980,and
unpublished data.
III--8
'------------------------,---------,..,,--_._-----------
-
-
;-
-
In Kaiser!s judgment,this forecast is warranted and probably
conservative due to the following factors:
(a)Alaska 's production of crude petroleum natural gas and other
minerals,particularly coal,limestone,and iron ore,is ex-
pected to increase substantially in the 1980s,both asa result
of new petroleum production in the North Slope and other
areas,and the increasingly short supply and high world prices
of mineral ores,which will encourage development of known
Alaskan deposits of these materials.Growth in distribution,
services,and government similar to that of the 1970s is ex-
pected to accompany expansion of these extractive industries.
(b)Alaska i s manufacturing s ector is expected to developsubstan-
tially in the 1980s,particularly if North Slope natural gas,or
gas from offshore sources,becomes available on the Gulf
coast.Alaska is in an excellent position to exploit domestic
and foreign export markets for gas-derivative petrochemical
produ cts and,also,to apply its r ela tively low-co st natural
gas as fuel to facilitate cement manufacturing,coal beneficia-
tion,and direct reduction of iron and other ores.At present,
both U.S.West Coast and Far Eastern markets for these prod-
ucts are heavily dependent on imports from the eastern U.S.
and other sources.As a result,Alaska's remoteness and high
labor cost,which typically have deterred local manufacturing,
are expected to be outweighed both by availability of resources
and the advantages of shipping them as semifinished products
from near the source of the raw material.Development of
these industries,which are relatively capital and labor-
intensive compared with crude oil production,should be accom-
panied by a high rate of activity in distribution,service,and
construction sectors.
(c)Alaska's expected revenues from oil and gas royalties,and
its outright ownership of royalties in kind,make the state
uniquely capable of controlling and encouraging local indus-
trial development and of providing the community facilities
and services necessary to mitigate impacts of population and
industrial growth.As a result,it is expected that the State of
Alaska itself will be capable both of promoting and assimilat-
ing a high rate of growth in the 1980s.
III-9
--,.;
,....
,..,...
-
D.ENERGY CONSUMPTION FORECASTS
The selected Su sitna proj ect servic e region,consisting of Anchorage-
Cook Inlet and Fairbanks Areas,cornprises all but a small part of
the population and employment of Ala.ska's Southcentral and Interior
Regions~as noted above"Therefor e,the growth tr ends forecast
for the Southcentral and Interior Regions as a whole have been taken
as representative of the service region.
At the present time,the Anchorage-Cook Inlet and Fairbanks Ar eas
are served by the following utilities:
Anchorage-Cook Inlet Area
,l<Chugach Electric As sociation,Inc.
~~{Anchorage Municipal Light and Power Department
Homer Electric As sociation,Inc.
Matanuska Electric Association,Inc.
Seward Light and Power Department
Fairbanks Area
*Golden Valley Electric As sociation,Inc.
>1<Fairbanks Municipal Utilities System
Of these seven utilities,four,indicated by asterisk (*),have regu-
larly operating generating capacity.In the Anchorage-Cook Inlet
Area,Chugach Electric and Anchorage Municipal Light and Power
deliver power to the other smaller systems,along with the Alaska
Power Administration,which supplies the systems in this area from
its Eklutna hydroelectric plant.
Records of these utilities for the period 1961 through 1973,compiled
by the Federal Power Commis sion and the Alaska Power Administra-
tion,have been used as the basis.for forecasting electrical energy
sales in the Susitna service region.Two categories of electrical
load were established for forecasting,following the most cons-istent
division of the recorded data:residemtial and an aggregation of
commercial-industrial and other uses.Other uses include sales
to public buildings and stl"eet lighting,which together c6mprise
about 5 %of total consumption.
III-10
-----------------------_._---_._._--_.._.
-
-
-
-
1.Residential Energy Sales
To forecast residential energy consumption in the Anchorage-
Cook Inlet Area,a correlation was established between population
of the Southcentral Region and the number and energy consumption
of individual customers in the Anchorage-Cook Inlet Area,In this
analysis,the data for 1961 through 1973,shown in Table III-5,
were first translated into logarithms.Using a computer,a reg-
ression analysis was then prepared,taking the change in number
of residential cu stomer s as the dependent variable and population
as the independent variable.The following formula was derived:
Log R =Log a +b(Log P)
where:R =number of residential customers
a =intercept on Y axis
b =factor describing slope of growth line
P =population
The result was as follows:
Log R =-4.11281 +1.6671l(Log P)
For the Fairbanks Area,no reliable formula could be obtained by
computer to forecast the number of residential customers.Popu-
1a tion changes occurring in the Interior Region,possibly because
of shifts in military personnel,wrere not immediately reflected in
comparable changes in number of residential customer s.For
Fairbanks,however,a relationship was noted between average
annual population growth from 1961 through 1973 and the average
annual growth in number s of residential customer s for the same
period.Growth factors derived £:rom this relationship were then
applied to the population.forecast to estimate energy consumption.
Using these data the following forecasts were made for energy
sales per customer in both areas through 1980:
III-11
----------_._-----~_..._._-------.-.-.....__._------_.....
Energy Sales per Residential Customer
l
~"-
-1961
1968
1970
1973
1980
Anchorage-Cook Inlet
(kwh)
5;130
6,480
7 1 830
9,280
-----------Forecast
13,000
Fairbanks
3 1 590
4,880
8,820
11,000
14,000
-----...__.._--_.-...__._----_.
.....
-
-
.~".
These forecasts of per-customer residential energy sales reflect
the following considerations:
(a)The average annual increase per capita income in Alaska be-
tween 1974 and 1980 will exceed the average annual gain of
5.7%recorded between 1959 and 1971 and will stimulate fur-
ther increases in energy consumption per residential
customer.
(b)A decline in the price of residential energy sales has undoubted-
ly stimulated consumption in both the Anchorage-Cook Inlet and
Fairbanks Areas,but this trend probably will not continue in
the last half of the 1970s.It is expected that rising costs,
particularly of fue1s 1 will lead!to leveling and possibly in-
creases in energy charges.
(c)The Fairbanks Area,with its <colder climate and its sharply in-
creasing use of electricity for home heating,will continue to
outpace Anchorage in consumption of energy per residential
customer.
2.Commercial-Industrial Energy Sales
Commercial-industrial energy sales for both the Anchorage-Cook
Inlet and Fairbanks Areas were forecast by identifying a correla-
tion between total civilian employment and numbers of customers.
Again using a computer program,the following formulas were
derived:
I
III-12 I
I........J
-
,t"_
",....1
For Anchorage:
For Fairbanks:
Log 0 :::-.446306 + •8777366(Log E)
Log 0 :::-2.4790,~+1.35334(Log E)
,-where:0 :::the number of nonresidential customers
E :::total civilian employnnent
Forecasts of the number of commercial-industrial and other cus-
tomers were next applied to separate forecasts for sales of energy
per cU$tomer through 1980,as indica ted in the following table:
Energy Sales per Commercial-Industrial Customer
-
-
-
1961
1965
1970
1973
1980
Anchorage-Cook Inlet
(kwh)
29,730
46,270
64,860
80,390
Foreca.st
148,000
Fairbanks
31,970
38,000
62,510
76,190
118,000
-
.-
In forecasting sales of energy per commercial-industrial customer,
the following factors were considered:
(a)Employment increases in distributive and service industries and
state government will be accompanied by growth in the average
size of commercial and industrial establishments and govern-
ment office buildings.
(b)The cost of commercial-industrial energy,which fell sharply
between 1961 and 1973,will tend to level,or possibly rise,as
generation and distribution costs are affected by inflation .
(c)In the Anchorage-Cook Inlet Area,energy consumption per
commercial-industrial custom€:r increased at an average annual
rate of 8.6%from 1961 through 1973,and is forecast to in-
crease at 9.10/0 from 1973 to 1980.
III-13
-------------
'.-
"'-,---------,,--,'-,---,---,---'------'--'---l
(d)In the Fairbanks Area,growth in energy c.onsumption per
commercial-industrial customer averaged 7.5%annually from
1961 through 1973,and is expected to increase at 6.4%annual-
ly from 1973 through 1980.
Tables 1II-4 and 1II-5 summarize records and forecasts of energy
consumption by residential and cornmercial-industrial service
categories for the years 1961 and 1980.
3.Nonutility Industrial and Military Energy Sales
Alaska Power Administration data indicate that today approxi-
mately 17%of Alaska's total electricity generation is by nonutility
industrial plants,and that 22%is by U.S.military installations.
Nonutility industrial generation is more or less evenly divided be-
tween the timber industry of Southeast Alaska and the petroleum
industry of Cook Inlet and the North Slope.The timber indu stry
utilizes wood scrap with a residual oil supplement for much of its
fuel,primarily to generate process steam;most of this industry's
electric power is then produced from a combination of fresh
steam and recycled process heat.In general,this type of indus-
trial power generation would not be replaced by utility sources
even if they were available,and would not contribute demand to a
project like Susitna 1.The oil industry generates its own power
in locations which either do not have established utilities,such as
the North Slope,or which are inaccessible to utility distribution,
such as the production platforms of Cook Inlet.Again,this mar-
ket is not capable of being serviced from utility sources and would
not enter into Susitna's demand base.
Past trends in utility load growth in Southcentral Alaska have in-
dicated that new industrial loads which local utilities can reach
will be connected.This has been true of the Kenai oil refining
and petrochemical industries,which are served by Homer Electric
Assn.,Inc.,and also of portions of the Alyeska Pipeline,which
may be served by Golden Valley Electric As sn.,Inc.In Kaiser I s
judgment,the forecast trends in industrial growth for the
Anchorage-Cook Inlet and Fairbanks Areas give reasonable
weight to prospective new industrialloada.
III-14
..-
TABLE 1lI-4
ENERGY SALES TO RESIDENTIAL AND COMMERCIAL-INDUSTRIAL
CUSTOMERS IN THE ANCHORAGE-COOK INLET AREA
1961-1973
Residential Customers
--- - ---- - ----- -----------F 0 RECA ST -,-- - - - - --- - -~------- --- - -
Energy Number of
Sales Customers
(million kwh)
--
--
-
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1980
108.9
12l.3
129.4
146.7
169.5
190.0
204.Z
22.7.6
256.4
302.4
362.0
416.3
45Z.8
1,135
21,as
12,17'(
23,443
24,813
26,164
27,278
28,690
3!,61?
34,428
38,589
41,765
46,983
48,880
87,300
Energy Sales
Per Customer
(kwh)
5,130
5,470
5,520
5,910
6,480
6,960
7,120
7,180
7,450
7,830
8,670
8,860
9,280
13,000
-Camme rcia r-Indus tria "'l Cus tome rs
Energy Nurnber of Energy Sales
Sales Customers Per Customer
(million kwh)(kwh)
1961 108.5 3,650 29,730
1962 125.7 3,776 33,280
1963 142.0 3,850 36,890
1964 153.0 3,904 39,190-1965 46,270185.9 4,017
1966 209.8 4,220 49,710
1967 239.7 4,391 54,590
1968 270.9 4,773 56,740
1969 304,3 5,011 60,no
1970 353.4 5,449 64,860
1971 409.4 5,812 70,450
1972 481.1 6,498 H,080
1973 546.7 6,800 80,390
-- - - - - --- --- - - ------- - - --FORE CA ST - -------- - ---- -_-------- --
1980 I,425 9.600 148,000
I~"·'·
Sources:1961-1967 Alaska Power Administration,"Statistics of Major
Utilities in the Railbelt Area.I'
1968-1973 Federal Power Com,mission,"Power Syste!n
Sta.tements."Cugach Electric Assn.,Inc.,Anchorage Muni-
cipal Light and Power Dept.,Homer Electric Alisn,,Inc.,
Matanuska Electric Assn.,Inc.,Seward Light ane!Power
Dept.,Alaska Power Administration,Eklutna Plant,Golden
Valley Electrlc Assn.,Inc.,Fairbanks Municipal Utilities
System.
Ill-I:;'
.-.1
!"'-~r
TABLE 1II-5
ENERGY SALES TO RESIDENTIAL AND COMMERCIAL-INDUSTRIAL
CUSTOMERS IN THE FAIRBANKS AREA
1961-1973
- - --- - - - - - - - - - - - - - - - - - - - -FORECAST --- --- - - - - - - - - - --- - - - ---
--- - - --- - ----- --- - - - -----FORECAST ..- --- - - ---- ----- - - - - - ---
Commercial-Industr ial Customers
-
-
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1980
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1980
Energy
Sales
(million kwh)
23.8
27.5
29.5
29.9
39.3
46.7
51.1
62.5
75.2
90.7
109.2
121.0
132.0
307
Energy
Sales
(million kwh)
34.8
39.1
43.2
54.6
54.0
58.0
63.5
81.8
89.5
117.2
132.4
138.9
160.0
440
Residential Customers
Number of
Customers
6,636
7,013
7,875
7,957
8,055
8,094
8,467
8,903
9,442
10,289
10,876
11,281
12,000
21,900
Number of
Customers
1,090
1,167
I,333
I,38:2
1,421
1,531
1,533
1,59!)
1,781
1,874
1,904
1,987
2.100
3,700
Energy Sales
Per Custome r
(kwh)
3,590
3,920
3,750
3,760
4,880
5,770
6,030
7,020
7.960
8,820
10.040
10,720
11,000
14,000
Energy Sales
Per Customer
(kwh)
31,970
33,500
32,420
39,530
38,000
37,850
41,400
51,290
50,230
62,510
69,510
69,880
76,190
118,000
I
I
I
I
I
I
I
I·
Source:See Table IlI-4.
-
,-------------_._------'----~----".~--'""
If new electric power supplies became available at sufficiently
low cost to induce large energy-intensive industries to locate in
Alaska,it could then become necessary to provide for a nonutility
inclustrialloacl sector in forecastingo However,it is evident that
the Susitna I project will have neither the prerequisite low cost
nor long-term capacity surplu s to do this o
It also appears inappropriate to include Do So military loads in the
forecasts for Susitna.In the past,Alaskan military bases have
been largely sel£-sustaining.AltllOugh in some cases inter-ties
have been set up with local utilities,these have not drawn or de-
livered significant net amounts of energy.Because the D.S.mil-
itary establishment in Alaska is now declining,a trend which
probably will continue in future,it appears that existing military
power plants should be adequate for futur e needs.
4.Total Energy Sales
Through 1980,total energy sales in the Anchorage-Cook Inlet
Area are forecast to increase at an average annual rate of 14.4%.
For the Fairbanks Area,annual growth is forecast at an average
14.4%.
For 1990,the growth trend for total energy sales has been forecast
based on the overall tr end from 1961 through 1980.For the
Anchorage-Cook Inlet Area,the average annual rate of growth
from 1980 through 1990 is expected to be approximately 13rro.For
Fairbanks it is forecast at 11 %.In both cases.these rates are
less than the trend forecast through the latter part of the 197050
Table III-6 summarizes the record of total energy sales in
Anchorage-Cook Inlet and Fairbanks }i.reas from 1961 through 1973,
with Kaiser's forecasts through 1980 and 1990.
For reference,these forecast data may be compared with forecasts
of individual utilities in the Ancho:rage-Cook Inlet and Fairbanks
Areas,and the Alaska Power Adrninistration as compiled in
Appendix Tables 1,2 and 3,
E.GENERATION AND PEAK LOADS
Proj ections have been made of power system generation or net energy
input and peak loads associated with the above forecasts.
111-]1
TABLE III-6
RECORD AND FORECAST OF
TOTAL ENERGY SALES
ANCHORAGE-COOK INLET AND FAIRBANKS AREAS
1961-1990
Record Anchorage-Cook Inlet Fairbanks
(million kwh)
Total
-
.-
1961
1962
1963
1964
19~5
1966
1967
1968
1969
1970
1971
1972
1973
217.4
246.9
271.4
299.7
355.4
399.8
444.0
510.6
577.9
673.6
785.1
892.4
996.3
58.7
66.6
72.7
84.6
93.3
104.6
114.5
141.5
170.3
211.4
250.7
259.8
291.0
276.1
313.5
344.1
384.3
448.7
504.4
558.5
652.1
748.2
885.0
1,035.8
1,152.2
1,287.3
--- - - --- - - - --- - --- - --- - - -FORECAST - - - - - - - - - - - - - - - - - - - - - _---
1980
1990
Source:
2,560
8,800
See Table III-4.
747
2,121
3,307
10,921
AILASKA RESOURfES LIBRARY
u.s.Department of ttM;!tn.t~rlm'
III-18
-
-
For this purpose,Federal Power Commission data on operations of
Anchorage-Cook Inlet and Fairbanks utilities have been compiled
and analyzed for the period 1968 thrc,ugh 1973.To compute net en-
ergy input,distribution losses for both areas were projected at a
long-term average rate of 7%.This rate is lower than the average
recorded losses of all but one utility from 1968 through 1973;how-
ever,a downtrend in losses is observable,and the higher rates ex-
perienced by some utilities in recent years are considered to reflect
long-distance transmission losses,equipment and operating prob-
lems,and recording errors,which either would not be present in the
future,or would not apply to energy received from Susitna o Addi-
tional transmission losses for Susitna itself are estimated in the
Power System Balance section,below.
To compute peak load resulting from forecast net energy require-
ments,system load facto'rs were examined also over the period 1968
through 1973.In both the Anchorage-Cook Inlet and Fairbanks Areas,.
there has been a trend toward higher system load factors.This trend
has been extrapolated through the forecast period,with an arbitrary
limit set at 62.5%for the Anchorage-·Cook Inlet Area system,and
60.0%for the Fairbanks Area systerrl.These load factors would be
relatively high for systems of comparable size in other areas;how-
ever,it is r ecogniz ed that Alaskan winter energy consumption pro-
videsa much more continuous load than typical in other areas.Al-
though the system load factors may eventually exceed these set limits,
it is considered more conservative to underestimate them for plan-
ning purposes,thereby allowing for a.margin of peaking capacity.
Operating statements of the four generating utilities and the Alaska
Power Administration do not indicate any significant diversity of peak
loads during the 1968-1973 period.
Table 1II-7 summarizes energy sales and recorded and forecast net
energy for system,and peak load,as well as system load factors
for the years 1968 through 1990.
F.POWER SYSTEM BALANCE
A power sy:;tem balance has been prepared for the Anchorage-Cook
Inlet and Fairbanks Areas for the comparative base period 1968
through 1973 and subsequently through 1990,as shown in Table liI,-8.
Capacity expansion plans for existing systems have also been com-
piled for the years 1974 through 1980;these are shown in Table III-9
III-lq
)
TABLE III-7
ENERGY SALES,NET ENERGY FOR SYSTEM,AND PEAK LOAD
ANCHORAGE-COOK INLET AND FAIRBANKS AREAS
1968-1990
Anchorage-Cook Inlet Fairbanks Total
-~-_...-
Energy Net Peak Load Energy Net Peak Load Energy Net Peak Load
Sales Energy Load l Factor Sales Energy Load Factor Sales Energy Load Factor
(million kwh)(t!)ou sand kw)-~(million kwh)(thousand kw)__"/<_0_(million kwh)(thousand kw)__0/._'_
Actua12
1968 510.6 559.4 125.0 51.0 141.5 160.8 42.7 42.9 652.1 720.2 167.7 49.0
1969 577.9 631.4 132.4 54.4 170.3 190.3
45.6 47.6 748.2 821.7 178.0 52.7
1970 673.6 739.8 153.5 55.0 211.4 235.9 57.1 47.1 885.•0 975.7 210.6 52.9
1971 785.1 873.2 178.3 55.9 250.7 279.3 65.1 49.0 1,035.8 I,152.5 243.4 54.1
1972 892.4 979.3 196.4 56.9 259.8 302.5 66.0 53.3 I,152.2 1,281.8 262.4 55.8
1973 996.3 1,089.8 213.0 58.4 291.0 318.4 72.5 50.1 1,287.2 1,408.3 285.5 56.3
F~
1974 I,140 1,220 3 238 4 58.5 333 358 3 764 53.8 1,473 1,578 314 57.4
197';1,305 1,400 271 59.0 381 410 87 53.8 1,686 1,810 358 57.7
1976 1,493 1,600 307 59.4 436 469 98 54.6 1,929 2,069 405 58.3
1977 1,709 1,830 349 59.8 498 535 111 55.0 2,207 2,365 460 58.7
1978 1,955 2,090 396 60.2 570 613 127 55.1 2,525 2,703 523 .58.9
1979 2,237 2,390 450 60.6 652 701 144 55.6 2,889 3,091 594 59.4
1980 2,560 2,740 513 61.0 747 803 164 55.9 3,307 3,543 677 59.7
1981 2,896 3,100 576 61.4 829 B91 180 56.5 3,725 3,991 756 60.3
1982 3,277 3,510 648 61.B 920 989 199 56.7 4.197 4,499 847 60.6
1983 3,708 3,970 729 62.2 i,022 1,099 219 57.3 4,730 5,069 948 61.0
1984-4,195 4,490 820 62.5 1,134 1,219 242 57.5 5,329 5,709 1,062 61.4
1985 4,746 5,080 928 62.5 1,259 1,354 266 58.I 6,005 6,434 1.194 61.5
1986 5,370 5,750 1,050 62.5 1,397 1,502 293 58.5 6,767 7,252 1,343 61.(,
1987 6,076 6,500 1,187 62.5 1,551 1,668 323 58.9 7,627 8,168 1,510 61.7
1988 6,874 7,360 1,344 62.5 1,721 1,851 356 59.3 8,595 9,211 1,700 61.8
1989 7,777 8,320 1.520 62.5 I,911 2,055 393 59.7 9.688 10,375 1,913 61.8
1990 8,800 9,420 1,7Z 1 62.5 2,121 2,281 434 60.0 10.921 11,701 2,155 61.8
I Based on recorded peak loads of Chugach Electric Assn••Inc.,Anchorage Municipal Light and Power Dept,Golden Valley Electric Assn.,Inc.and Fairbanks Municipal
Utilities System;individual years adjusted 1-6%for Alaska Power Administration sales to Matanuska Electric Assn.•Inc.and other minor generation.
2 Federal Power Commission,"Power System Statements,"1968-73 for utilities indica.ted in Table 111-4.
3 Computed from energy sales,assuming distribution losses at 7%..
4 Computed from net energy,based on load factors shown.
III-20
)
TABLE llI-8
POWER SYSTEM BALANCE
ANCHORAGE.COOK INLET AND FAIRBANKS AREAS
1968-1990
1968 19M 1970 1971 1972 1973 1974 1975 1976 ,1977 1978 1979 1980 1981 1982 1983 1984 1985 -!-9 8 6 1987 1988 1989 1990
~ta as of ye~d (thousa~)
Anchor ..ge -Cook Inlet Area
Peak Load 125.0 132.4 153.5 178.3 196.4 213.0 238 271 307 349 396 450 513 576 648 729 820 928 1,050 1,187 1,344 1,520 1,721
Existing and planned
dependable capacity 189.I 192.6 210.9 230.9 284.6 325.6 429 444 497 552 552 552 552 552 552 552 552 552 552 552 552 552 552
(Ie ..)system reserves (51.0)(51.3)(48.0)(48.0)(64.1)(99.5)(108)(123 )(123 )(123)(123)(123)(123)(123 )(123)(123 )(123)(123 ) (123)(123 )(123)(123 ) (123)
Assured capacity l38.T i4T.3 i62.9 182.9 ~226:""T"321 321 374 429 429 4Z9 429 4Z9 429 4Z9 """429 429 """429 429 429 429 429
OrIginal balance 13.I 8.9 9.4 4.6 24.I 13.I 83 50 67 80 33 (21)(84)(147)(219)(300)(391)(499)(621)(758)(915)(1,091)(1,292)
New dependable
Capacity:
Othe r than Su sitna 1 21 84.84 84 84 84 84 154 350 569 780 1,021
Su sitna I 66 149 263 364 500 583 550 518 518 518
(Ie.,)Susitna I Josses (3).L2l L.!.U L~.!..El ~(28)(26)(26)(26)
Subtotal 63 142 252 348 478 554 522 492 492~
(less)adjusted reserves (7)(36)(41)(63)(87)(114)(146)(181 )(221)
Adjusted balance 13.I 8.9 9.4 4.6 24.I 13.I 83 50 67 80 33 -0--0--o·-D.-0--o.-0--D-00.-0--0--D.
Fairbanks Area
Peak Load 42.7 45.6 57.I 65.I 66.0 72.5 76 87 98 III 127 144 164 180 199 219 242 266 293 323 356 393 434
EX1Sting and planned
dependa ble capacity 70.8 76.I 104.3 112.8 130.8 130.8 131 131 131 184 184 184 237 237 237 237 237 237 237 237 237 237 237
(Jess)system reserves (28.5)~.LE.2)~~.L..E.:2l (~(34)(34)(53)(53)(53)(53)(53)(53)(53)(53)(53)(53)(53)(53)(53)(53)
Assure-d capacity 42.3 64.9 72.0 80.5 97.1 97.I 97 "9'f 97 I3T l3T l3T'lii"4 """"i""84 ""Tii4 l1l4 184 184 184 184 184 l84 184
Original balance (0.4)19.3 14.9 15.4 31.I 24.6 21 10 (I)20 4 (13)20 4 (15)(35)(58)(82)(109)(139)(172)(209)(250)
New dependable
Capacity:
Other than Susitna I 6 12 21 66 113
Su.itna I 16 38 62-88 117 150 182 182 182
(Jess)Susitna I losses (I).I 3)(4)(6)(8)(II)(13)(13)(13)
Subtotal .--""'l5 35 -----sa ----sz l<i9 l"3"9 """i69 """i69 "'"i"(;9
(less)adjusted reserves (6)(12)(18)(26)(32)
Adjusted balance (0.4)19.3 14.9 15.4 31.I 24.6 21 10 (I)20 4 (13)20 4 -D·-0-.0--0--0--0--0--0--D·
1II-21
..~
--})
TABLE 1ll-9
PROJECTED INST ALLA TlON OF NEW
GENERATING CAPACITY
ANCHORAGE-COOK INLET AND FAIRBANKS AREAS
)
Anchorage-Cook Inlet Area
Planned capacity:
Beluga 4 &5
Anchorage 8,9 &10
Other capacity (not sized)
Fairbanks Area
Planned capacity:
North Pole 1
Healy 2
Other capacity (not sized)
Susitna I:
Units 1 &2
Units 3 &4
1974
7 fl.0
40.0
1975
15.0
1976
70.0
55,0
1977
53.0
1978 1979 1980 1981 1982 1983
Data as of year end (thousand kw)
53.0
350.0
1984 1985
350.0
1986
70
6
1987
196
6
1988
219
9
1989
211
45
1990
241
47
1ll-22
along with the proj ected commis sioning schedule for Su sitna and other
capacity requirements to occur before and after the Susitna project.
1.Criteria
In preparing the power system ba.lance,Federal Power Commis-
sion datal on existing systems!dependable capacity and reserves
were compiled for the comparative base period 1968 through 1973,
Generally.during this period.system reserves were relatively
high as a percentage of peak load due to the fact that each of four
utility systems maintained a reserve more or less equal to its
largest unit,plus some minor standby capacity.Over the period
1974 through 1990,system reserves for both the Anchorage-Cook
Inlet and Fairbanks Areas have been projected at 20%of peak load,
or the size of the largest generator unit in the system,whichever
is greater;in general the 20%ratio is the governing factor.Com-
pared to previous reserve ratios in the region.the projected
reserve levels are relatively low and may have the effect of very
slightly under stating demand for the Susitna proj ect.
During its fir st four year s of operation.from late 1981 through
1985.the Susitna project will add a substantial capacity surplus
to the system.This will make it unnecessary to add capacity dur-
ing this period for the purpose of increasing system reserves.Be-
ginning in 1986.it is assumed that additional reserves will be in-
stalled at other locations.
Susitna transmission losses of peak power have been estimated at
5%of Anchorage-Cook Inlet peak demand on Susitna and 7%of
Fairbanks peak demand.The resulting overall energy loss is es-
timated at 1.25%.Losses for other remote plants in the system,
such as Beluga.Healy.and North Pole,which are nearer their
respective load centers are estimated at 3%of peak demand.
2.System Capacity Requirements
IlI-?3 J
Since 1969,the Fairbanks Area has had proportionally greater
capacity surpluses than Anchorage-Cook Inlet;however,present
system development plans indicate a less adequate margin over
demand through 1978.A small but significant capacity deficit is
indicated for the Fairbanks Area in 1979,but the installation of
new capacity in 1980,as now planned,should be capable of restor-
ing a surplus through late 1982.
Commissioning of Susitna is projlected for October 1,1981,at
which time 4 x 175,000 kilowatt turbine-generator units would be
ready for service as shown in Table III-9.Capacity of the Susitna
project is assumed to be allocated according to immediate demand
in the Anchorage-Cook Inlet and }i'airbanks Areas until it is fully
utilized.The resulting shares would correspond to the relative
peak loads of the two areas;Anchorage-Cook Inlet would receive
74%and Fairbanks would receive 26%.
As indicated in Table III-la,98%of the 700,000 kilowatt peak ca-
pacity of Susitna I would be required as assured capacity by the
end of 1986,approximately five year s after commis sioning,with
100%utilization in the following year.From 1986 through 1990,
the Anchorage-Cook Inlet Area would require an additional 927,000
kilowatts of new assured capacity,while the Fairbanks Area would
require 113,000 kilowatts during the same period.
3.Susitna I Generation
It is not considered necessary to prepare a complete system en-
ergy balance in order to estimate consumption of Su sitna I energy.
In general,past installation of thermal capacity for peaking has
provided the system with a substa.ntial excess energy capability,
becau se the system load factor,which in 1973 averaged approxi-
mately 56%,is less than the optirnal plant factor for most fuel-
fired plants.As a result,the Susitna project has been designed
to a 55%plant factor,on the basis of which energy output of the
system l B thermal capacity may be increased to a more optimal
65%plant factor by 1988.In each year of operation,the Susitna
project is assumed to supply new peak demand as indicated in the
system balance,with corresponding primary generation computed
at its design plant factor.During the years 1981 through 1986,
III-24
-.-._,-,----
)-I 1 I 1 1
)
TABLE III-10
CAPACITY AND SALES PROJECTION
Peak Demand Net 3
Net Energy Sales
Dependable Anchorage 1
Fairbanks 2
Energy
Year Capa~~Cook Inlet Total Capability Primary Surplus
(thousand kw)(million kwh)
1981 330 63 -63 1,515 158 1,357
-
1982 330 135 15 150 3,030 733 2.297
1983 330 216 35 251 3,030 1.265 1,765
1984 330 307 58 365 3,030 1,832 1,198
1985 661 415 82 497 3,180 2,498 682
1986 661 537 109 646 3,330 3,263 67
1987 661 522 139 661 3,330 3,330
1988 661 492 169 661 3,330 3,330
1 Losses excluded @5%
2 Losses excluded @70/0
3 Losses excluded @ (average)1.25%
i
t:::
H,
N
111 ~
-
-
when Susitna has surplus energy capability.it is as sumed that
it will be operated at 100%of its continuous energy capability and
that surplus energy will be sold in the system at a reduced rate
to replace use of fuel by the systern's thermal plants.
Estimated Susitna energy deliveries are shown in Table III-IO,and
provide the basis for Susitna project revenue estimates.
-
-
III-2.()
IV.HYDROLOGY
A.STUDY INFORMATION
Hydrologic studies were based on mean monthly river discharges re-
corded at U.S.Geological Survey gaging stations and precipitation
records of climatological stations as described b~low:
.....
River Gaging Stations
Susitna River
Gold Creek
Cantwell
Denali
Maclaren River
Paxson
Years of Record
Oct 1949 -Sept 1972
May 1961 -Sept 1972
June 1957 -Sept 1966
and July 1968 -Sept 1972
June 1958 -Sept 1972
(23 )
(11)
(10)
(5)
(13)
Climatologic?l Stations
and Elevation -ft Years of Precipitation Records
Big Delt&
Gulkana
McKinley Park
Snowshoe Lake
Summit
Talkeetna
Gracious House
Trims Camp
B.PAST STUDIES
1,268
1,570
2,070
2,410
2,401
345
2,550
2,405
30
31
43
11
32
43
3 (some records missing)
16
-
,,.....
Hydrologic studies and subs equent power generation studies for the
Devil Canyon project were based on runoff records of the Susitna
River at Gold Creek Station for the lO-year (period from October
1949 through September 1959.Use was made of runoff data from
the Denali Station which began operation in May 1957 and the Denali
data were extended to cover the 1949-1959 period by correlation with
the runoff data from the Gold Creek Station.The runoff data for the
Devil Canyon site were derived by a straight-Hne relationship between
drainage areas and incremental runoff.
IV-l
1---,-------------",,-------
I
J
The Devil Canyon Status Report of May 1974 made use of the same
data described above without further study of hydrologic data for
years later than 1959.
C.UPDATED STUDIES AT GOLD CREEK
Hydrologic data for the years 1950 to 1972 were gather ed by the Henry
J.Kaiser Company early in 1974.
Examination of the data for the Gold Creek Station revealed the oc-
currence in 1969 of a new low in annual runoff at this station.The
main information resulting from examination of the 23 -year runoff
record at the Gold Creek Stat~on is summarized as follows:
Average Annual Runoff,
acre-feet
Minimum Annual Runoff,
acre-feet (year)
Ratio of Minimum to Average
1950-1959
Record
7,139,500
5,815,000 (1950)
81%
1950-1972
Record
7,131,000
4,052,000 (1969)
57%
l""'.'
In the 23-year record,the 1970 inflow was second lowest at
5,496,000 acre-feet and the 1950 inilow was third lowest.Only
three of the 23 years have a runbff of less than 6,500,000 acre-feet.
D.RUNOFF AT PROPOSED DAMSITE
Damsite ,B as proposed by the Henry J.Kaiser Gompany for the loca-
tion of Susitna I is on the Susitna River between two gaging stations.
The upstream station,called Cantwell,is near Vee Canyon and the
downstream gaging station is near Gold Creek.Records for the sta-
tion near Gold Creek are available for the 23 water years 1950-1972
(see Appendix Table 4),and records for Cantwell station are available
for eleven water years 1962'-1972 (see Appendix Table 5).The 11
years of joint records were used to compute monthly coefficients to
adjust the Gold C reek flows to the proposed damsite.With this set of
coefficients and the Gold Creek runoff records,23 years of records
of monthly runoff were computed for Damsite B.In Appendix Table 6
these estimated flows at the damsite are presented in acre-feet'per
month.
'.IV -2
1-__-,,-..__--'-..:'......
The evaluation of these coefficients utilized the ratio between the
average monthly discharge for the 11 years of overlapping Gold Creek
and Cantwell records and the ratio between the drainage areas of the
damsite and the two gaging stations.
The formula used to compute the monthly coefficient is as follows:
The coefficient is used as shown below:
where:
Q =Average monthly discharge for 11 water-years (1962-1972)
°1 =Average monthly discharge for the gaging station at Gold Creek
Q2 =Average monthly discharge for the gaging station at Cantwell
~
AD =Drainage area in square miles for the damsite
.-Al =Drainage area in square miles for gaging station at Gold Creek
A 2 =Drainage area in square miles for gaging station at Cantwell
--
The coefficient will be obviously higher during the summer months
due to the glacier runoff and snow melt coming from the high eleva-
tions and due to the high summer precipitation.(For monthly coeffi-
ci~nts,see Figure IV -1 at the end of this chapter.)
In order to simplify the calculations and because the discharge d\+ring
seven months is only approximately 12%of the total annual discharge,
an average annual coefficient for the year was computed from the
average monthly distribution of runoff and the monthly coefficients.
E.IMPACT OF NEW DA TA
From exainincHion of the hydrologic data for the years fromL9 50 to
1972 inclusive,it was evident that the two succes sive dry years of
1969 and 1970 would have a significant impact upon the results of
studies based on hydrologic information prior to 1969.
IV-3
I
I
j
-~In order to assess the impact of these dry years,the probabilities of
annual discharge volume at the proposed damsite were calculated.
The probabilities of annual discharge equalling or exceeding a re-
corded event were calculated by use of the following equation:
Probability ~-~n +1
where m =rank
n =number of recorded events =23
TABLE IV-I
PROBABILITIES OF ANNUAL DISCHARGE AT THE
PROPOSED DAMSITE ON THE SUSITNA RIVER
,,,,,..,,...
Discharge-Water Year (acre-feet in thous;ands)Rank Probability
1962 7795.81 1 4.2
1956 7735.52.2 8.3
1967 7562.10 3 12.5
,1963 7463.43 4 16.7
I 1972 7341.14 5 20.8
1961 7287.11 6 25.0
1959 7117.53 7 29.2
1957 6999.25 8 33.3
1955 6912.20 9 37.5
1971 6910.11 10 41.7
1965 6852.54 11 45.8
1953 6801.32 12 50.0
1968 6616.17 13 54.2
1964 6607.06 14 58.3
1960 6549.25 15 62.5
1954 6525.52 16 66.7
1952 6438.94 17 70.8
1958 6386.99 18 75.0
1966 6356.97 19 79.2
1951 6138.25 20 83.3
1950 5413.57 21 87.5
1970 5116.38 22 91.7
I19693772.32 23 95.8
I!-
I
I
IV-4~
Table IV -1 indicates that the minimum annual discharge at the pro-.
posed damsite,calculated to be 3,772,320 acre-feet,would be equalled
or surpassed nearly 960/0 of the time,
To further evaluate the frequenc y of extremely low river runoff,the
overall basin runoff for years of record at Gold Creek was studied
with respect to measured annual precipitation in the region.The an-
nual precipitation records for three stations which coincided with the
Gold Creek station record period were examined.These stations
were Gulkana to the southeast,Talkeetna to the southwest,and Sum-
mit to the northwest.The Denali station records were not sufficiently
complete for use in this analysis.
Precipitation data from the three stations were used to relate the
frequency of occurrence of ranges of precipitation depth to the fre-
quency of occurrence of the same ranges of overall basin runoff
depth as measured at Gold Creek.The results are shown in Table
IV-2,below.
TABLE IV-Z
FREQUENCY OF OCCURRENCE
Depth,Inches
Overall Basin
.Runoff at Gold
Creek
Precipitation
Talkeetna Summit'Gulkana
5-10
10-15
15-20
20-25
25-30
30-35
35-40
40-45
*1969
**1950,1970
2*:::::
18
2
23
1
1
4
9
7
o
1
23
1
2
13
5
2
23
10
13
23
In the year of lowest runoff at Gold C reek--1969 --the precipitation
was also the lowest recorded at all three stations;in addition,it was
IV-5
I
J
.,...:..
-
-
the lowest of 43 years of records at the Talkeetna station.The uni-
form distribution of the annual depths of rainfall at Gulkana is clo se-
ly related to the continental climate in this area.
F.LONG RANGE HYDROLOGIC STUDIES
Preliminary computations of discharge on the Susitna River by re-
gression analysis on climatological data and by Stochastic Hydrology
indicate that the frequency of extremely low annual runoff events will
be less than indicated by the shorter term historical records.
1.Gold Creek Station--Regression Analysis Computations
The discharge records at the Gold Creek Station for 23 years were
used to extend the discharge records to 30 years by regression
analysis using river runoff and precipitation records.
The best prediction of one dependent variable can be obtained from
another independent variable or variables by determining mathe-
matical models of correlative association of two or more variables.
The models are called regression functions.
Several conditions which precluded the development of an optimal
multiple correlation model are as follows:
•Insufficient numbers and/or location of rain gage stations in and
around the drainage basin to give representative basin precipita-
tion records,
•Lack of useful temperature records,and
•Short duration of all records.
The results of the regression analysis conducte~indicate,however,
that there is sufficient precision to extend the recorded occurrence
of low annual runoff.
The developed regression equation for calculating annual runoff at
Gold Creek gave a multiple correlation coefficient of 0.8434.
The regression equation developed in this study is based on 23
years of annual discharge at Gold Creek and on 22 years of pre-
cipitation records at Talkeetna and Gulkana.
IV-6
-~"~"-'-"-'---'---'---"'---------------------------_.__._---_......_._..,_._--_._.__J
log Q 2 =3.52958 +0.358166 x log
log Q =3.52958 +0.358166 x logn
-
The Talkeetna station is almost entirely dominated by maritime
influenc es,where the Gulkana station represents continental cli-
matic conditions in the South of the Alaska Range.Based on
numerous correlation calculations among eight climatological sta-
tions in the North and the South of the Alaska Range,it was estab-
lished that precipitation records in the South of the Alaska Range
are much more representative of climatic conditions in the Susitna
River Basin.
The annual records for the water years were taken in order to
eliminate the influences of winter storage and snow melt.
Volume changes of the glaciers,temperature fluctuations,as well
as precipitation in the previous year,are expressed partially in
the equation by the discharge of the previous water year.
The equation for the annual runoff at the Gold Creek Gaging Sta-
tion is:
log Q l =3.52958 +0.358166 x log p~+0.314512 x log p~+
0.362557 x log QO
1 2
P2 +0.314512 x log P 2 +
0.362557 x log Q 1
1 -2
P .+O.3 14512 x 10 g P +n n
0.362557 x log Qn-l
where:
on
Qn-l
=Discharge in acre-feet of water year n at the Gold Creek
Station.
=Discharge in acre-feet of the previous water year n-l at
the Gold Creek Station..The average of the 1950-1972
records (00 =7,131,000 acre-feet)was assumed for the
first year.
=Annual precipitation at Talkeetna in inches for the water
year n,and,
=Annual precipitation at Gulkana in inches for the water
year n.
I
IV-7 ).....-l
Using climatplogical data for the water years 1943-1949,the an-
nual runoff at Gold Creek and at the proposed damsite were calcu-
lated.The annual runoff for both stations IS as follows:
Annual Discharge in 1,000 acre-feet for the Water Year
Station 1943 1944 1945 1946 1947 1948 1949
Susitna River
at Gold Greek 7956 8258 9133 7941 9046 7844 8065
Susitna River
at the Pro-
posed Site B 7407 7689 8503 7393 8422 7302 7508
As a consequence of the above-mentioned results,the frequency of
th e extr em el y low annual runoff in 1969 will be 3.2 %ins t ead of
4.2%(see Figure IV-2).The studies extend the period of hydro-
logic records from 23 to 30 years and the extremely low flow of
1969 would occur one e in 30 year s.
The regression equation predicts an average annual runoff from
1950 to 1972 at Gold Creek of 7,133,313 acre-feet,which is 0.03%
higher than the average annual recorded runoff of 7,131,000 ac re-
feet.The average annual estimated runoff at Gold Creek for the
extended period of 1943-1972--7,410,260 acre-feet as derived by
the equation--is 4%higher than the measured average annual re-
corded runoff for the historical period of 1950-1972.--7,131,000
acre-feet.
With 43 years of precipitation records at the Talkeetna rain station,
an extension for cODlputing additional 13 years wOItld have belm
possible.Since there are no other rt'cords available for the
Gu!kana Station,any further regresSilll1 analysis must be based
either on one or more new favorable variables,or on a different
regression function which expresses better the relation between
Gold Creek discharge and Talkeetna precipitation.
In order to assess further the reliability of the extremely low an-
nual runoff predictions,it is expected that additional detailed
evaluations of regression analysis functional relations between
runoff and climatological data would be made in the next stage of
the work.These studies could provide estimates of the accuracy
of the confidence interval of the predicted stream flpws.
IV -H
-
-
,-
-'
,-
--·---------·----·----·-1
2.Gold Creek Station--Stochastic Hydrology'Computations
These calculations were made to extend the discharge records at
Gold Creek.They made use of the computer program No.723-
X6-L2340 which was prepared in the Hydrologic Engineering
Center,U"S ..Army Corps of Engineers at Davis,California.
This program analyzed monthly stream £lows at interrelated
gaging stations on the Susitna River to determine their various
statistical characteristics and generated a sequence of hypothetical
stream flows of the desired length having those characteristics.
In order to get complete records over 23 years for all the gaging
stations,missing stream £lows for the stations at Denali,Maclaren,
and Cantwell were first constituted,utilizing all available monthly
discharge records of the Susitna River gaging stations--Denali t
Maclaren River,Cantwell,and Gold Creek.To obtain the mis sing
values,a regression equation in terms of nOrmal standard vari-
ables was computed by selecting required coefficients from the
complete correlation matrix for that month and solving by the
Crout method.
Next,77 years of hypothetical stream £lows at Gold Creekwere
generated.The multiple correla.tion regression equation developed
in reconstituting the historical stream £lows was solved simultane-
ously on a step-by-step basis..A Stochastic random variable term
was added to the solution process.The 23 years of historical re-
cords at Gold Creek station and the 77 years of generated £lows
provide 100 years of usable monthly discharge records.
The results show that there are only two years in the range of 4.5
to 5.0 million acre-feet annual discharge (the minimum recorded
annual discharge was 4,052 million acre-feet).The maximum
historical annual discharge.of 8,373 million acre-feet is exceeded
by four events.Although these results do not give the same ac-
curacy as the regression analysis,the probability of a year as dry
as 1969 would still be quite low,statistically.Independent factors
such as very low precipitation over the whole basin and low
temperCl:-tures almost everywhere in the basin have to occur simul-
taneously to give such a low £low year.As the probability of these
two events individually is quite small,the probability of their oc-
curring simultaneously is exceptionally small.Therefore,the re-
sults seem to be understandable for the magnitude of the basin
IV -9
----------------~-------
-
-
-
investigated;however,further detailed investigation by Stochastic
Hydrology methods will improve the degree of obtained accuracy.
From these studies it would appear that the frequency of occur-
rence of the extremely dry year of 1969 would be even lower than
one year in thirty.
IV -10
I
I
.-.1
I
0.94
0.93
0.92
0.91
1 1 1 1 \I 1 ,.~1 I i 1 1 .I
))
FIGURE IV~1
COEFFICIENTS RELATING SUSITNA RIVER RUNOFF AT
GOLD CREEK TO RUNOFF AT SITE B
-,I '"'"
SELECTED ANNUAL,
COEFFICIENT.K:=0.931 ~---1-.------10-__
l-
ff
I ""~/
V ~~~MONTHLY COEFFICIENT
OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
-
-
-
V.TOPOGRAPHY AND GEOLOGY
A.INTRODUCTION
~
In order to make a preliminary assessment of the technical feasibility
of constructing the Susitna I hydroelectric project at the selected Site
B,a geologic reCOllna is sance of that site and other a rea s of intere st
was made in late June 1974.The prime objectives of thi.s reconnai.s-
sance were to identify the type of rock,assess its general condition,
and to assess any features of terrain and geologic structure which
would affect location,design and construction of the proJect.In addl-
tion,it was necessary toassess the availability of construction nlat-
erials,and of materials suitable for use as concrete aggregates.
The reconnaissance was made in a fixed wing aircraft for general
overall observations supplelnented by use of a helicopter to provide
access for on-the -gro und ob se rvation s.
B.TOPOGRAPHY
The topography at the selected site conforms generally with the one
inch to the mile maps prepared by the United States Geological Survey.
The canyon is generally V -shaped.The average slope of the north
abutment is about 45 0 for the first 500 feet above the river;above this
the slopes flatten to about 25°up to a height of 1,000 ft:et above the
river.The south abutment slopes upward at an angle of 45 0 for the
first 200 feet above the river;for the next 800 feet the slope averages
about 25°.In the steepest part of the canyon,r'ock walls on each side
rise almost vertically for several hundred feet above the river leveL
At the higher elevations on both sides of the river the terrain becomes
noore rounded.While the north abutment of the canyon is covered with
dense forest extendillg to the uplands,the forest on the south abutment
thins several hundred feet above the river to patches and islands of
trees,and the uplands have very little tree cover.
C.GENERAL GEOLOGY
1.Glacial Deposits
The site area has been extensively glaciated and is mantled with
glacial and nonglacial deposits.The glacial materials consist
primarily of moraines and eskers composed of erratic lenses and
V -1
L---_.__._.____._..•_..•.,...........__•._.•_.__.._.•
-
-
-
-
layers of sand,rounded to angula.r gravel and cobbles,boulders,
silt and considerable rock flour.Some older glacial deposits ex-
hibit considerable weathering evidenced by iron stains and chemi-
cal alteration.
Material size ranges from rock flour to boulders three feet in di'-
ameter,with a high percentage of material larger than four inches
in diameter.Because of the high content of rock flour,and with
the exception of occasional granular pockets or stringers of sand,
the moraines should be impervious.
2.Talus and Swamp Deposits
The nonglacial materials are primarily talus,outwash,and swamp
deposits.Talus material,unsorted.angular to subangular.occurs
generally on the south abutment area and a.lso near the base of gul-
lies and cliffs on both sides of the canyon.It is almost entirely
granitic in composition and is derived from adjacent outcrops.The
blocks range in size from a few inches to 15 feet in maximum di-
mension.Deposits on the upper bench areas probably do not ex-
ceed 10 feet in thickness;however,on the steep slopes of both
abutments they average about 20 feet in thickness and locally may
be as much as 40 feet in thickness.
Swamp and muskeg deposits occur on benches on the south abutment
in areas of poor drainage.The deposits are composed of moss and
low shrubs mixed with fine sand,gravel,and silt.These deposits
generally are less than three feet thick and are underlain by mo-
raine and outwash.
3.River Terraces and Gravel Bars
River-deposited terraces and gravel bars occur several miles up-
stream of the damsite.They are composed of coarse to fine sand,
subrounded to rounded gravel and boulders observed to five feet in
diameter.The terrace gravels on the river floor extend to about
60 feet above the river level with an unknown thickness below river
level.The rock composition of the materials varies from phyllite
to granite to basalt.
V-2
--_.,_..,--._--_.----_.
1 "1 1 I l 1 l
')
1 1 1 )J \')I
FIGURE IV-2
PROBABILITY DISTIUBUTION OF ANNUAL DISCHARGE AT THE PROPOSED DAMSITE BON SUSITNA RIVER
BASED ON RUNOFF RECORDS FOR GOLD CREEK STATION AIID CANTWELL STATION
(REF TABLE v·31.
99.99 99.9 99 95 90 80 70 60 40 !O 10 5 2 1 0.2 0.05 0.01
sooo
7000
I-
lIJ
l1J
U.
W
!r
U«
o
8
~6000
W
~
!r«
:I:
U
~o
...J«
:::l
Z
Z
«5000
if000
,
"'"•
'"~;-~AVERAGE DISCHARGE =6,639.000 AF ~
"\
•
~
I IL'.M ,.,",'"'""""'""..".,"...
I
,;-
-
----------
4.Bedrock
The bedrock on the site,as observed in mas sive outcrops on both
sides of the river is a fine-grained granitic roc k composed mainly
of quartz,feldspar,biotite.and hornblende.Well-developed sets
of regional joints occur in the damsite area.The major joint set
bas a strike that is almost perpendicular to the river channel;it
averages about N 25 0 W but varies from due north to N 45 0 W.The
dip averages 80 0 east but varies from 65 0 east to vertical.
Two prominent and well-developed shear or fault zones occur on the
north abutment,but are obscured by overburden on the left abutment.
These two zones have caused the formation of near-vertical V-shaped
gullies;they appear to have a general strike of N 25 0 Wand a dip
ranging from 80 0 NE to vertical.These two fault or shear zones are
located upstream of the proposed dam,on the north abutment;on the
south abutment they may intersect the proposed diversion tunnels
near their entrances.In that area on the south abutment,however,
a diabase-like intrusion is exposed,and it appears that this under-
material has deflected the course of the river at this point.From
aerial and ground reconnais sance and air photo interpretation there
does not appear to be any faulting or rock structure dislocation par-
alleling the river.
The steep escarpment faces in the river canyon have resulted in
large blocks 15 to 20 feet high distinctly separated from adjacent
bedrock on the north abutment.No conspicuous faults or displace-
ment features were noted in the south abutment escarpment area
adjacent to the river.There appears to be no appreciable depth of
weathered rock on either abutment.
D.ENGINEERING GEOLOGY
Aerial reconnaissance supplemented by a study of existing geological
data indicates that the reservoir basin will be tight at the selected site
for Susitna 1.
1.North Abutment
The most obvious features of the north abutment are the two well-
developed shear or fault zones.
V-3
-
....
.....
....
....
The sheared rock is not well healed,and intensive fracturing with
open crevices is common.It was not pos sible to estimate a lateral
or vertical displacement in the fault zone.As noted above,fissures
15 to 20 feet deep were observed in the steep escarpment faces near
the river.
The upstream toe of the dam is located several hundred feet down-
stream of the nearest shear zone.While further geologic investi-
gation is required,the occurrence of the shear zones would appear
unlikely to affect the stability or performance of a rockfill dam.
The occurrence of fis sU,res in the bedrock foundation of a rockfill
dam are significant only to watertightness of the foundation which
will be remedied as necessary by the customary foundation treat-
ment techniques.
2.South Abutment
There is no observable evidence that the two shear zones of the
north abutment extend to the south.If these zones do continue on
the south abutment,they might intersect the upstream ends of the
diversion tunnels but this occurrence would present no major con-
struction problems.The rock structure of the escarpment face at
the river shows no conspicuous faults or displacement features.and
joint faces are well healed.The diabase intrusion at the bend up-
stream of the dam is an extremel~'competent,fine-grained dark
grey rock mass;it displays a uniform set of joint planes dippingoabout5to10southeast.
This abutment will require more excavation to remove deposits of
soft overburden and to remove or spread talus materials.The
bedrock appears to be tight,and no particular problems are anti-
cipated in cut-off curtain grouting .
3.The Riv.erbed
Due to the depth and velocity of river flow,no observation of river-
bed was pos sible.The depth of boulders and gravel above bedrock
may range from 30 to 60 feet.Although it will be necessary to ex-
cavate through to bedrock where the impervious membrane of the
dam meets the riverbed,the main body of the rockfill dam can be
founded on the compact river gravel-boulder mass.
V-A
l
-
.-
4.Spillway
The spillway will be located on the south abutment of the dam and
nominal grouting may be anticipated under the crest structure.
The unlined and stepped discharge channel will be excavated in
massive granite which is expected to be highly resistant to erosion
by spillway releases.
5.Underground Powerhouse and Tunnels
The restricted topography and favorable geological conditions indi-
cate the desirability of an underground powerhouse in the south
abutment.The competency of the granite bedrock indicates the
possibility of excavating an underground chamber and various tun-
nels with a minimum of support.Deep drilling,of course,will be
required to fully outline the problems which may arise during con-
struction of the powerhouse chamber and the various tunnels.
Because the powerhouse will be located below the dam impoundment
level,extensive grouting may be necessary to prevent water inflows
through joint and fracture systems.
6.Construction Materials
The granitic bedrock materials are adjudged to be well suited for
the construction of a rockfill dam and would also be suitable for
use in the manufacture of concreb~aggregates.The occurrence
of natural sands and gravels appears to be limited to small river
terraces and gravel bars located upstream of the damsite.These
deposits are composed of fine to coarse sand,subrounded to
rounded gravel and cobbles,and boulders ranging up to five feet in
diameter.The rock materials include greywacke,phyllite,granite,
and basalt.A terrace deposit ranging in height to 60 feet above
river level is located about 3-1/2 miles upstream of the site.
Glacial deposits at elevations ranging upward from the 2,ODD-foot
contour are comprised largely ofa silty rock flour with inclusions
of generally angular rock fragments.These areas are generally
barren except for a thin muskeg cover.The silty rock flour ap-
pears to be suitable for use as impervious material and similar
glacial till has been used for that purpose in other northern areas.
From 01'1-site observations,the exploitation of moderate quantities
of impervious materials appears to be economically feasible.
V -5
,-
-
-
----,._---,---..-..-------_...,----,-------~
I
7.Permafrost
Permafrost may be encountered in access road construction and
the exploitation of borrow materials.It will be encountered in
transmission line construction.
V -6
--..._-,-----------------------"-----
-
.~
-
VI.POWER STUDIES
A.INTRODUCTION
For the Kaiser proposal on the Susitna project.a preliminary eval-
uation of the power capability of the river was made,using hydro-
logic data contained in the U.S.Bureau of Reclamation (U.S.B.R.)
II Devil Canyon Project Report,II of May 1960.These data covered
the period from October 1949 to September 1959.After submission
of the Kaiser proposal,hydrologic data for the full 23-year period
from October 1949 to September 19'72 became available,and these
data were used for the power studies described herein.
u.S.Geological Survey topographic maps were used to prepare
reservoir area capacity curves and to estimate tailwater elevations
at the selected project site,in conjunction with topographic data
furnished by the Alaska Power Administration.
The monthly energy and peak load requirements upon which the
power studies were based,were taken as percentages of total annual
energy generation and annual peak load respectively.These percent-
ages are the same as used in the U.S.B.R.Devil Canyon report and
are as follows:
"'-
Month
January
February
March
April
May
June
July
August
September
October
November
December
Monthly Load Distribution
(%of annual total)
9.3
8.1
8.3
7.7
7.6
7.2
7.4
7.7
8.0
8.9
9.4
10.4
Monthly Peak Load
(%of annual peak)
89
87
81
71
67
63
68
71
81
89
94
100
VI-l
-
-
-
For these studies an average hydraulic efficiency of 82%was u sed on
gross head.On the basis of the preliminary layout of the project,
the operational range of the project,and the operational range of the
reservoir,this efficiency is considered to be reasonable.
The result of this initial assessment indicates that the economic
maximum normal level of the reservoir is 1,.750 feet elevalion.A
more detailed study should be made when improved data on topography,
hydrology,and geology become available.As in the U.S.B.R.Devil
Canyon report,reservoir evaporation was considered to be negligible.
B.OPERATION STUDIES
Initial operation studies were made to ascertain the firm continuous
power which could be generated over all 23 years of hydrologic rec-
ords.Under this criterion,firm continuous power was found to be
325,000 kw,with corresponding annual energy generation of 2,837
million kwh;this was governed by the extremely low water year of
1969.
If hydroelectric power from the Susitna River was the sole input to a
power system,its nominal continuous power would necessarily be
limited to the lowest predictable dry year inflow.However,Susitna
power will be integrated into a system comprised of natural gas and
coal-fired thermal generating plants,.as well as other hydroelectric
plants.This system is considered to have sufficient energy capability
to meet system requirements in a low water year by operating on a
higher than average plant factor.Therefore,analyses were
made to develop criteria whereby thE:Susitna reservoir co'Uld be op-
erated to produce a higher level of continuous power in normal years
with a curtailed output in an isolated extremely dry year.On the
basis of the 23 years of water records,two reservoir rule curves
were established,as shown in Figur,e VI-I,at the end of this chapter.
When the reservoir level is on or above the upper rule curve,actual
power generation should equal or exceed normal firm continuous
power;that is,secondary power may be generated.When the reser-
voir level is between the upper and lower rule curves,power genera-
tion should be equal to normal firm continuous power.When the
reservoir level is below the lower rule curve,power generation must
be curtailed below the normal firm continuous level to allow the
reservoir to recover the upper rule curve.
VI-2
1 ----,....._.__••._.,
-
~.",-------~-----
Power studies carried out on the basis of the two reservoir operating
rule curves resulted in firm continuous power of 385,000 kw for the
period from October 1949 to May 1969,and also from December 1970
to September 1972.For the dry year cycle,between June 1969 and
November 1970,firm continuou s power was 250,000 kw.The studies
also indicated that the higher level could be increased to 390,000 kw,
with a corresponding dry cycle level of 210,000 kw.As noted in the
hydrologic studies,Chapter IV,the probability of occurrence of the
1969 low water year is less than one in thirty;therefore,energyout-
put of the Susitna project would be curtailed less than 3%of the time.
To substantiate whether the higher continuous power figure could be
used for system planning,an analysis was made of the projected
power system balance for the Anchorage-Cook Inlet and Fairbanks
ar ease As shown in Table VI-I.a dry year occurring in 1985 would
impose the most stringent operating conditions on thermal units of
the system.The annual average load factor for thermal units in a
1985 dry year would be 82.9%;re-regulation of the Susitna reservoir
could pr event monthly load factor s from exceeding this leveL It is
believed that it would be feasible for the thermal units in the system
to maintain this level of operation in an isolated dry year.Beyond
1985,addition of other assured ther:mal capacity would reduce the
system thermal load factor to be maintained in a dry year.
The conclusion of this analysis is that the proj ect can be based on
firm continuous power of 385,000 kw,with corresponding firm annual
generation of 3,372 million kwh.Using a plant factor of 55%,the re-
sulting Susitna I installed capacity is 700,000 kw.
Reservoir operation rule curves are presented on Figure VI-I.This
drawing also shows inflow,outflow,and elevation,and average
monthly power generation when the reservoir is operated to these
rule curves for the 23-year period of record.Typical yearly load
curves are also shown for normal years and for an extremely dry
year.
Table VI-2 presents a summary of a.nnual operating data for the 23-
year period of runoff records.
C.COMPARISON WITH THE U.S.B.R.DEVIL CANYON PROJECT
,The power and energy capability of the U.S.B.R.Devil Canyon proj-
ect'as described in the 1960 and 1974 Project Reports,was based
VI-3
---------------._----------_.._-----....-.-_.__.,..----_._-.._---.--_.----.
<......
I
*'"
TABLE VI-l
SUMMARY OF THERMAL LOAD FACTORS
UNDER NORMAL AND DRY YEAR CONDITIONS
Net Energy Susitna Thermal Assured Thermal
for Generation Generation Thermal Load Factor
Year System Normal Dry Year Normal Dry Year Capacity Normal Dry Year
(million kwh)(million kwh)(thou sand kw)%
1980 3,543 --3,543 -697 59.6
1981.3,991 158 -3,833 -697 63.8
1982 4,499 733 -3,716 -697 60.9
1983 5,069 1,265 -3,804 -697 62.3
1984 5,709 1,832 -3,877 -697 63.5
1985 6,434 2,498 2,190 3,936 4,244 697 64.5 69.5
1986 7,252 3,263 2,190 3,989 5,062 697 65.3 82.9
1987 8,168 3,330 2,190 4,838 5,978 849 65.1 80.4
1988 9,211 3,330 2,190 5,881 7,021 1,039 64.6 77.1
1989 10,375 3,330 2.190 7,045 8,185 1,252 64.2 74.6
1990 11,701 3,330 2,190 8,371 9,511 1,484 .64.4 73.2
I~_~.----"..,-\.t
').)J .))J 1 )J
".
j 1
)
TABLE VI-2
ANNUAL SUMMARY
RESERVOIR AND POWER OPERATION
Year Release Reservoir
Ending for Content Firm Secondary Total
Sept.30 Inflow.Power Spill End of Year Energy Energy Energy
1,000 acre-feet (million kwh)
1949/50 5,414 5.7Z2 -5.364 3.373 -3,373
50/51 6.138 6,016 -5.486 3,373 -3.373
51/52 6,439 6.253 -5,673 3.373 292 3,665
52/53 6,801 6,801 -5,673 3.373 740 4,113
53/54 6,526 6,463 63 5.673 3,373 499 3.872
54/55 6.912 6,867 45 5,673 3,373 752 4.125
55/56 7.736 7,140 596 5,673 3,373 921 4,294
56/57 6,999 6,811 188 5.673 3,373 742 4,115
'57/58 6,387 6,431 -5.629 3.373 537 3,910
58/59 7.118 6.652 422 5.673 3,373 597 3.970
59/60 6,549 6,322 227 5,673 3,373 438 3,811
60/61 7,287 7.268 19 5,673 3,373 1.049 4.422
61/62 7,796 7,584 212 5.673 3,373 1.220 4,593
62/63 7,463 6.978 485 5,673 3,373 858 4,231
63/64 6,607 6,607 -5.673 3,373 565 3,938
64/65 6,853 6,690 163 5,673 3,373 636 4,009
65/66 6,357 6,357 -5.673 3,373 448 3,821
66/67 7.562 7,052 510 5,673 3,373 846 4,219
67/68 6,616 6,616 -5.673 3.373 621 3,994
68/69 3,772 5,416 -4,030 3,084 -3,084
69/70 5.116 4,184 -4,962 2,205 2,205
70/71 6,910 6,198 -5,673 3,373 138 3,511
;S 71/72 7.341 7,341 -5,673 3.376 1,055 4,428
I
'"Mean 6,639 6,512 127 3,309 563 3,872
)--.-}--
"'
-
-
on the hydrologic record for the years from October 1949 to Septem-
ber 1959,and the low water year of 1950.From the analysis above,
it is believed that r easses sment of the power capability of the Devil
Canyon project using the full 23 years of runoff records would signif-
icantly r educe this proj ectr s power capability if the dry year were
considered to govern.Of course p this project would also become
part of the same system with the probable result that its normal
firm continuous power capability would be only slightly reduced from
the level shown,and that thermal generation could be used to supple-
ment its dry year generation.
The Devil Canyon proj ect and Susitna I may be compar ed as follows:
Continuou s power
Load factor
Installed capacity
Annual ener gy
Devil Canyon
330,000 kw
550/0
600,000 kw
2,900 million kwh
Susitna I
385,000 kw
55%
700,000 kw
3,372 million kwh
....
The peak power and energy generation ofSusitna I is 16.6%greater
than that of the Devil Canyon project•
....
--
-
VII,CONCEPTUAL PROJECT STUDIES
A.INTRODUC TION
The project concept originally advanced by the Henry J.Kaiser
Company as ail alternative to the U.S.B.R.Devil Canyon Project,
consisted of a single high dam located near Devil Canyon with a
power plant located at or near the dam.This concept was aimed
at the formation of a re servoir in a location where the water released
from the re servoir could be used directly for power generation.
This concept would eliminate Denali dam and reservoir from the
first stage of river resources development at least and at the same
time significantly reduce the effect of first stage river development
upon the natural environment.
In the initial studies an alternative concept was considered.This
secondary concept was comprised of a dam and power plant several
miles upstream of Devil Creek,shown as Site D ,'_combined with,a
dam and power plant just downstream of Portage Creek;shown as
Site A on Figure VIL-l,at the end of tbis chapter.
Comparative studies of these two concepts which included evaluation
of power potential,increased length of access,and transmission
facilitie s indicated that the original concept of a single project instal-
lation was the more favorable.Consideration was given in each case
to location of the power plant further downstream;however,the gain
in head from fall in the river was not sufficient to justify location of
the power plant beyond the immediate vicinity of the dam.
B.SELECTED PROJECT CONCEPT
1.General
The main features of the selected project concept designated as
Susitna 1 are a.dam approximately 800 feet high,aspillwa,y con-
trolled by three tainter gates,a power intake and tunnels which
carry water to generating unih in an underground powerhouse,
a switchyard and a transmission system which supplies electric
power to the Anchorage-Cook Inlet and Fairbanks areas.The
location of the project is shown on Figure VII ..-l and the layout of
the main project features is shown on Figure VIl-2.
I
1
VII-l
'---------------------------------------------------------
,-------------------------_.__.
2.The Dam
-
-
-
--
Consideration was given to three general types of dams;namely,
concrete arch,concrete gravity and,compacted rockfill.All
three types have been built in other locations to heights exceeding
that of the darn required lor the project concept"While concrete
arch darns are usually well suited for V-shaped canyons,the
spread of the V at Site B was considered too wide for an arch darn.
The cost of a concrete gravity darn,considering especially the
limited availability of naturally occurring sands and gravels,was
not competitive with the cost of a rockfill darn.
Two types of compacted rockfiU dam were considered,the sloping
core type and the concrete face type.The main structural element
of the sloping core type darn is the downstream rockfill zone.
This is overlain by the impervious earth core which is protected
by several layers of sand and gravel filters at the upstream and
downstream faces of the core.The core and filter zones are
overlain by upstream rockfill which provides structural stability 1
for the impervious earth zone.The principle of the vertical
core type of darn is similar.Co:re-typ~dams of si:milar
height range include Mica Dam in British Columbia which is 800
feet high;Oroville Dam in California,774 feet high;Chivor Dam
in Colombia which will be 727 feet high when completed in 1975.
Nurek Dam,now under construction in Russia,will be about
1,040 feet high when completed.The sole structural element
ofthe concrete face type of rockfiU dam is a single rockfill zone.
This zone is similar in size and performs the same function as
the downstream rockfill zone in the inclined core type rockfiLl
dam.The dam is made impervious by a reinforced concrete face
which varies in thickness from top to bottom of the darn.The
concrete face is underlain by and bonded to a zone of graded rock-
fill limited to maximum rock size of six inches.Existing major
darns of this type include Exchequer Dam in California and
Anchicay Dam in Colombia,both 500 feet high.The proposed
Areia Dam now being designed by a Kaiser affiliate in Brazil
will be 520 feet high and the proposed Yacambu Dam in
Venezuela wiLL be 540 feet high.
A concrete face type of rockfill dam has been tentatively selected
for use in the conceptua L project.Recent progre s s in improvement
of concrete face da~s due to increased knowledge and major im-
provements in rockfill design favors the use of such dams to
heights greater than presently established.The dam proposed in
VII-2'--------------------------------------_..•_.__._~.__._..__..
---_.-.~-_.__._._--_.,-------------------,
ItehairSthc~nocreePtovhearslabl.enenb ITlaOduifpi:td eb :f use ofkfa1'lc
l
onven~iOnthal limO perv
3
i
O
o
O
us _(
~y n .,r dITl roc z on e mewe r
feet.This earth core and rockHill is placed over the lower 300
feet of concrete face and the lower part of the daITl thus has two
distinct impervious barrier s.The height of concrete face con-
stituting a single impervious barrier is about SOD feet,the same
as Exchequer and Anchicay dam.s,The typical dam.section and
profile are shown on Figure VII-3,
The m.odified concrete face rockfill dam has been tentatively
selected over the conventional.core type rockfHl dam for the
following reasons:
(a)Availability of Materials
The core type of dam requires a m.uch larger volume of
impervious earth than the selected type,It also require s
sands and gravels for protective filter zones.Field recon-
naissance indicated that the volumes of these materials
readily available for economic darn construction is relatively
limited.It is anticipated that filter materials would have to
be produced by crushing rock.
(b)Volume of Dam
The volume of the core type of dam would be 30 to 400/0 greater
than the concrete face dam and could require a s much a s two
years longer to complete.
(f)Clim.ate
Frequent rainfall and low tem.peratures during the seven to
eight month darn construction season would inhibit placement
of the irnpe rvious ea rth core 'Nhich requires careful moisture
control.
(d)Diversion and power tunnels would be longer with the core
type of dam.
A s noted,the selection of the cone rete face type of dam as
modified is tentative.More field exploration for materials and
more detailed study and analysis are required before final selec-
tion of rockfiU dam type can be made.
VII.·.<,
-
-
3.Spillway
The spillway'will be located on the south abutment of the dam as
shown on Figure VII-2.The main elements of the spillway are
the approach channel,the control structure,and the discharge
channel.
The concrete control structure will be provided with three 40-foot
wide by 45-foot high tainter gates.The control structure will be
de signed to pa s s the de sign flood with a re se rvoir surcha rge of
five feet.The design flood,which will have a peak inflow of
213,000 cubic feet per second and a fifteen-day volume of
2,460,000 acre-feet,was established in the Devil Canyon Status
Report of May 1970.
The spillway discharge channel wi.ll be paved and lined with concrete
walls for a distance of about 100 feet downstream of the control
structure.The remainder of the channel will be unlined.Down-
stream of the initial sloping section,the spillway discharge chan-
nel will be excavated in a series of 50-foot high steps down to river
level as shown on Figure VII-3.With this arrangement,much of
the energy of the spilled water will be dissipated by the time the
water reaches the river.The discharge channel will be located
well away from other project features,and final release will be
in the direction of river flow.Th.e fine-grained granite bedrock
will be well suited for the cascade type of flow which has been
successfully .used in other projects.Rock derived from excavation
of the spillway will be used in construction of the dam.
4.Power Features
a.Intake
I
The intake structure will be located upstream of the dam on the
south abutment.It consists of two intake units,each servicing
two generating units in the powerhouse.Each intake unit will be
equipped with a semicircular steel trashrack and an hydraulically
operated fixed wheelgate.Two concrete-lined tunnels will con-
vey water to the powerhouse area where each tunnel will bi-
furcate into two steel-lined tunnels which will deliver water to
the turbines.
VII-4
-
-
-
.....
-
b.Powerhouse
An underground powerhouse ha s been tentatively selected for
the project,and it is located under the dam on the south
abutment as shown on Figure VII-2.The tailrace tunnels
will discharge into the diversion tunnels.
The tentative selection is based on the apparently favorable
rock structure of the south abutment,and consideration of
the very steep and narrow canyon at river level as well as the
severe winter climate.
The total installed generating capacity will be 700,000 kilowatts,
and tentative selection has been made of four 175,000 kilowatt
generating units •
The 241,OOO-horsepower Francis turbines will be equipped
with electrohydraulic governors and each turbine will be
provided with a butterfly valve at the entrance to the scroll
case.The generators will be rated at 194,000 kva,13.8 kv
with a power factor at O.90 and will be equipped with static
excitation.They will be capable of operating at an overload
capacity of 15%.The generators will be coupled with six single
pha se transformer s each rated at 75,000 kva,13.8-230 kv.
High tension cables will be carried in a tunnel from the power-
house to the switchyard.
Major powerhouse equipment will be installed and serviced by
twin 3S0-ton capacity bridge cranes.
S.Transmission System
The transmis sion system consists of a single circuit 230 kv line
to Fairbanks,.a double circuit 230 kv line to Anchorage,and
substations at both of these line terminals.
6.Sedimentation
In studies carried out by the Bureau of Reclamation in 1963,it was
estimated that without upstre~m storage,sediment inflow to the
Devil Canyon area would amount to 593,000 acre-feet in 100 years.
The reservoir visualized for the Susitna I project has a total
capacity of the order of 5,670,000 acre-feet,and the effect of·
one hundred years of sedimentation would be of no consequence.
VIl-5
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17eo
THE HENRY J.KAISER COMPAJ.JY
SUSITNA I
HYDROELECTRIC I"RI7JECT
RESERVOIR OPERATION
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SUSITNA I
HYDROEI..ECTRIC PROJECT
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THE HENRY J.KAISER.COMPANY
!SUSITI-IA 1
HYDROE..ECTI'tIC PRO.JECT
GENERAL LAYOUT
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HYDFlOEL.ECTRIC PROJECT
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VIII.COST ESTIMATE AND CONSTRUCTION PLAN
A.SUMMARY
The estimated cost of Susitna -I,by project features,is shown in
Table VIII-I.This estimate was based on June 1,1974 cost levels
for major equipment items.materials,and civil construction of the
project.Included in the estimate are provisions for escalation of
prices during the construction period.Also included are allowances
for engineering design,supervision of construction,administration
of contracts,contingencies,and interest during construction.
The total estimated cost for the project at completion of construction,
excluding interest during construction,is $525.72 million.Assuming
an interest rate of 6%,interest capitalized during construction would
total $77.0 million,the resulting total investment in the project would
be $602.72 million.as detailed on Table VIII-I.
The estimated cost for supply,transportation,and installation of·
major items of permanent equipment was based on information sup-
plied by equipment manufacturers.The estimated cost for construc-
tion of main project features was based on analysis of the construction
methods which would be used.Analyses were made of construction
plant and equipment r~quirements,along with labor force,and mate-
rials ands,upplies;costs were built up in the manner required for
actual bid preparation.All costs were based on latest material prices
applied to Alaskan conditions and recent Alaskan trade and craft labor
rates.The transmission system cost estimate was based on available
data,including recent experience,on the cost of constructing high
voltage transmission lines in Alaska.
B.CONSTRUCTION PLAN
1.Climate
The climate of ceiltral Alas ka is the factor which most affects the
timing and certain costs of project construction.In the past years
the heavy construction season in similar climates has been gener-
ally limited to the six months from April to September inclusive.
SpeciaHzed techniques developed in the construction of similar
projects in winter climates have,however,enabled extension of
the construction season from mid-March to mid-November.
VIII-l
._-------------------------------------------
TABLE VIlI-l
SUMMARY OF CAPITAL COST ESTIMATE I
(June 1974 Costs)
Hydroelectric Plant
1
,.-
.-
Site Access,reservoir clearing,and
diversion tunnels
Dam and spillway
Power plant and related facilities
Living quarters and general property
Transmission System
Total construction costs
Interest during construction
TOTAL CAPITAL INVESTMENT
$47,185,000
263,690,000
129,570,000
2,880,000
$443,325,000
$82,395,000
$525,720,000
$77,000,000
$602,720,000
lThe above costs include conting~ncy and engineering costs but do not
include escalation to the date of award of the construction and equip-
ment contracts.
VIII-2
~-_._-----------------------------_._-,----,---,-_.,-"....-
'....
-
Freezing temperatures at the extremes of this construction season
would have relatively little effect on excavation of rock and place-
ment of rock in the dam,particularly considering the low precipi-
tation in the area in those months.Certain l1nderground operations
can continue on a year-around basis,once well established,and
some above-ground concreting can be carried out in sub-zero
temperatures.
2.Access
In order to expedite the start of project construction and economi-
cally reduce the overall length of the construction period,it is
proposed to start work on the acces s road one year before the
award of main construction contracts.The road would be sched-
uled to provide reasonably good access for the first stage of con-
struction at the site and would be later improved for the movement
of major construction eq uipment and materials.It is as sumed that
the road would commence at Gold Creek,and during the early
years of the project,project supplies and equipment would be
carried to that point via the Alaska Railroad.Later the road
would be extended to the Anchorage-Fairbanks Highway to facili-
tate routine acce s s.
3.Diversion
Two tunnels have been tentatively selected for diversion of the
,river from its normal channel.Cofferdams will be placed up-
stream and downstream of the dam,and the downstream cofferdam
will be incorporated in the toe of the dam.In the first stage of dam
construction,rockfill will be placed to the full length of the dam in
the riverbed.To provide for the possible occurrence of a major
flood flow in the first diversion season,the downstream toe of the
rockfill will be reinforced with a network of steel wire mesh and
welded steel reinforcing bars.In the event that major flooding
causes overtopping of the initial low dam portion,the toe rein-
forcement,used in other similar projects,will prevent damage
to the rockfill.The following season the dam will be raised high
enough to route major river floods through the diversion tunnels.
After closure,the diversion tunnels will be used as part of the
powerhouse tailrace.
VIII-3
-
.-
.-
.....
'-"
..
4.Major Excavation and Dam Fill
The largest construction operation will consist of the excavation
of rock and its subsequent placement in the darn.Rock for the
darn will be derived partly from excavation required for construc-
tion of the spillway,intake,powerhouse,and switchyard.It will
al.so be taken from one or more quarries that will be established
in the reservoir area near the darn.The use of several major
sources of rock will permit more efficient use of excavation equip-
ment and will minimize the congestion of traffic transporting rock
frorn source to the darn.Major excavation will be planned so that
rock can be placed in the dam at or near the level from which it is
excavated.
5.Underground Construction
The scale of underground construction required for Susitna I is
comparable to projects of similar size and scope in many parts of
the world.Once initial access to underground works is achieved,
no unusual problems are anticipated,either in construction or in
the installation of permanent equipment.
6.Transmis sion System
While the transmission lines wUl traverse some difficult terrain
and permafrost will be enc~untered,'no um~sua.l copstruction
problems are foreseen at this time.
C.CONSTRU CTION SCHEDU LE
A tentative schedule has beenpr~paredfor the implementation of the
project,and is shown on Figure VIII-I.It is estimated that fii"st
power can be generated about six-and-one-half years after commence-
ment of work on the project.
About two-and-one-half years will be required for the completion of
preconstruction engineering.This will include site mapping,detailed
geologic inve.stigations and the preparation of designs,specifications
and documents for construction and equipment supply contracts.
Documentation required for project licensing by the Federal Power
Commission will be prepared in the early stages of engineering work.
'\
VIII-4
"'l--'-......;;._"~_=__.~_...,'.~.•...__.,_..._._,....--1
-
Construction of the access road is scheduled to commence about one
year after the start of engineering and work on the diversion tunnels
is scheduled to start six months later.The contract for construction
of the main project features is scheduled for award about two years
after the start of engineering,and contracts for the supply of major
items of permanent equipment would be awarded during the following
six-rnonth period.Transmission system engineering and constructiop
would be phased to provide for the transmission of power to the An-
chorage area upon generation of first power,and to the Fairbanks
area one year later,as required by present electrical load growth
forecasts.
VIII-5
-----------------
L
I
.J
")
,1 l }I J J 1 I i 1 l)
FIGURE VIII-1
SUSITNA I
TENTATIVE CONSTRUCTION SCHEDULE
YEARS
1974 1975 1976 1977 1978 1979 1980 .1981 1982 1983 1984 1985
ENGINEERING _______-----
ACCESS ROAD --DIVERSION TUNNELS _______-------
SITE PREPARATION
DAM CONSTRUCTION _ _ _____--_..---------
INTAKE
EXCAVATION _______------------
CONCRETE
EQUIPMENT __________-----------------
SPILLWAY
EXCAVATION _______~------------
CONCRETE
EQUIPMENT ____.____---------------
POWERPLANT
1 2 3 4
EXCAVATION ____------------j I IICONCRETE-.-
EQUIPMENT _ _ _ _ _ _------------
SWITCHYARD
,
EXCAVATION ______-----------
EQUIFMENT
TRANSMISSION SYSTEM
I
I
l..INES _ _ _ _ _ _ _----------
SUBST ATIONS
)!)}
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IX.FINANCIAL EVALUATION AND ECONOMIC ANALYSIS
A.INTRODUCTION
The financial and economic evaluations have been based on the tenta-
tive construction schedule shown on Figure VIII-lo The schedule
visualizes the commencement of detailed engineering in early 1975,
the commissioning of the first two generating units in 1981 and sec-
I
ond two in1985,in accordance with the projected load growth of the
a:t"eas to be served by the project.
B~FINANCIAL EVALUATION
L Method
A pro forma income statement has been prepared for Susitna I in
order to determine whether the projectr s schedule,costs,and
revenues are consistent with a practical financing method.
This analysis takes into account total costs estimated for the
project,along with projections of revenues to accrue from sales
of primary and surplus energy.
The pro forma income statement is presented as Table IX-L
2.Financing Plan
It is believed that if the Susitna project were undertaken by the
State of Alaska,a state issue of tax-exempt revenue bonds would
be the most practical method of financing the major part of its
cost.It is considered possible that leveraged lease financing
could be used for major equipment items,comprising 10 to 20%
of total cost,reducing the magnitude of the revenue bond issue
by a corresponding amount.The use of these financing methods
would require that the project be capable of obtaining firm com-
mitments for revenue power sales to its utility cu stomer s,and
possibly that the project's financial obligations also be guaranteed
by the State of Alaska.
In order to make best use of the term of the revenue bond issue,
it is assumed that bonds would be sold approximately six months
prior to project comm.issioning,although bond market conditions)~~
\.
I
1L _IX-1
)
TABLE IX-l
PRO FORMA INCOME STATEMENT AND
SOURCES AND APPllCATlONS OF FUNDS
1987-
Total 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 2015
T};';;USands of Dollars ($000),except as noted
R-evenues
Primary Energy Sales
kwh (thousands)--1?8,000 733,000 1,265,000 1,832,000 2,498,000 3,263.000 3,330,000
Revenue @ $.01447 --2,286 10,607 18,305 26,509 36,146 47,216 48,174
Surplus Energy Sales
kwh (thousands)---1,357,000 2,297,000 1,765,000 1,198,000 682,000 67,000
Revenue @ $.0082 11,127 18,835 14,473 9,824 5,592 549
Total Revenues -13,413 29,442 32,778 36,333 41,738 47,765 48,174
Annual Costs
Operating Cosfs @ .00205 310 740 7(,0 780 1,050 1,308 1,308
Interest Paytnents @ .06 0 .35,213 36,614 37,451 38,066 38,288 38,288
Depreciation @ .01 2,855 6,028 6,176 6,307 6,344 6,381 6,381
Total Annual Costs 0 -3,165 41,981 43,550 44,538 45,460 45,977 45.977
NET INCOME -10,248 (12,539)(10,772)(8,205)(3,722)1,788 2.197
Source!of Funds
Net lncotne .-10.248 (12,539)(lO,772){8,206}(3,722)1,788 Z,197
Depreciation -2,855 6,028 6,176 6,307 6.344 6,381 6,381
Debt
Bond Pyoceed.s or Notes 5(,1.100 1,600 17,400 69,000 75,700 109,600 128,800 91,800 31,900 14,800 13,100 7,400
Capitalized Interest 77,000 50 620 3,250 7,780 13,800 21,790 29,710
"~
Total 638,100 1,650 18,020 72,250 83,480 123,400 150,590 134,613 25,389 10,204 11 ,201 10,022 8,169 8,578
Applications for Funds
CDnstruction Program 561,100 1.600 17,400 69,000 75,700 109,600 128,800 91,800 31,900 14,800 13,100 7,400
Interest During Construction 77,000 50 620 3.250 7,71\0 13,800 21,790 29,710
Subtotal 638,100 1,650 18,020 72,250 83,480 123;400 150,590 121,510 31,900 14,800 13,100 7,400
Sinking Fund @ .0126 -0 -2,042 8,040 8,040
Total 1,650 18,020 72,250 83,480 123,400 150,590 121,510 31,900 14,800 13.100 9,442 8,040 8,040
NET CASH SURPLUS
(DEFICIT)-0--0--0-00_-0--0-13,103 (6,511 )(4,596)(1,8'i8)580 129 538
Cumulative -13,103 6,592 1,996 98 678 807 1,345 16,409
IX·2
)
//
))
-
-
-
might indicate a different date.In the interim,it is assumed
that bond anticipation notes would be issued to finance construc-
tion,following the issuance of a Federal Power Commission
license for the project.
Prior to federal licensing of the project,it would be necessary
to provide a source of interim funding sufficient for prerequisite
engineering and environmental studies.Although preliminary
commitments to purchase the proj ect l s power may be obtained
from prospective utility customers prior to this initial funding,
it is recognized that an element of uncertainty would remain
which would prevent use of revenue bonding at this early stage.
This uncertainty involves the possibility that in-depth site inves-
tigations,definitive cost estimates,complete environmental re-
ports,or unforeseen conditions could indicate that the project
was not capable of being carried forward.As a result,it is be-
lieved that State of Alaska general obligation bonds would be the
most practical method of financing these initial project expendi-
tures.These bonds would later be refunded by the project's
revenue bond issue when the project could adequately guarantee
its financial obligations.
3 ..Terms of Financing
The following outline of terms of financing has been used:
-
Revenue bond financing as percent
of total capital investment
Interest rate or gross yield,for
revenue bonds,general obligation
bonds,and anticipation notes
Sale of revenue bond issue
Term and type of revenue bond issue
Fir st payment of in terest
First sinking fund payment
80-100%
6%
Fir st quarter 1981
30 year sinking fund;
5 years grace
First quarter 1982
Fourth quarter 1985
IX-3
--
-
-
-
-
.-----------,....-----------------_._------
If leveraged lease financing were used,it is expected that its
term.s would be sim.ilar to those for the revenue bond issue,ex-
cept that the rate of interest should be O.5%to O.75%lower.It
is possible that the lessor would provide advance funding to re-
place use of anticipation notes for the portion of project cost to
be covered by the leveraged lease contract.
4.Pro Farm.a Incom.e Statem.ent Param.eters
a.Analysis Period
The pro form.a incom.e statem.ent covers each unique year of
project operation from.1975 through 1987.Following 1987,
individual year 1 s data are assum.ed to be identical,throughout
a financial period extending through 2015,when bonded in-
debtedness is fully am.ortized.
b.Operating Costs
Operation,maintenance,and adm.inistrative costs are charged
as 0.15%of total capital investm.ent for the hydroelectric plant
and O.5%for the transm.ission system.,averaging 0.205'%for
the project as a whole.Operating costs are reduced to 60%
of normal from.m.id-198l through m.id-1985,prior to installa-
tion of Units 3 and 4.
c.Interest
Interest during construction is com.puted sem.iannually as sum.-
ing that the m.ean point of each year l s capital expenditures is
at m.id-year.Following project comm.issioning,interest is
com.puted as a constant annual charge accompanying sinking
fund repaym.ent of debt.
d.Depreciation
Depreciation is listed as a noncash charge based on 100-year
s ervic e life.
e.External Cash Flow and Secondary Financing
No cash flow other than revenues from.energy sales is applied
to cover the cash obligations of the project.
I
I
..-I,
IX-4 I
..._----~._---
----~._-_._._-----_.__._-._-----_.-._._".__._-'--
f.Surplus
.-
_.
Under the revenue base selected for the project~a net cash
surplus is generated equal to O.10/0 of total capital investment
in the hydroelectric plant beginni,ng in 1987.Surpluses aver-
aging approximately 50%of this level are generated in 1984,
1985 and 1986.
Applicable fixed and variable annual charges are summarized
in Table IX-2,
g.Revenues
Revenues are computed from the schedule of primary energy
required by the system,plus surplus energy available from
Susitna I during its early years of operation.Primary energy
is charged at 14.47 mills per kilowatt hour,the average en-
ergy charge computed for the complete proj ect.Surplus en-
ergy is assumed to be salable at 8.2 mills per kilowatt hour,
the projected least cost of fuel in the Anchorage-Cook Inlet
Area.In this analysis,no allowance has been made for the
difference in Anchorage-Cook Inlet and Fairbanks Area rates,
which could slightly affect some years l revenues.
5.Cone lu sian s
This analysis indicates tha.t the proposed construction program
for Susitna I and related estimates of costs and revenues are
consistent with a practical method of financing the project and
repaying its indebtedness.
C.ECONOMIC ANALYSIS
1.Cost of Susitna I Power by Service Ar~
Using the project financing and operating cost criteria outlined
above,the average cost of net energy delivered by Susitna I is
computed at 14.47 mills per kilowatt-hour,including 12.13 mills
per kilowatt~hour for generation and 2.34 mills for transmission,
as shown in Table IX-3.This average cost is not equally alloc-
able to the Anchorage-Cook Inlet and Fairbanks service areas
because of two factors.First,the Anchorage-Cook Inlet Area
is expected to drawSusitna I energy on a slightly higher load
IX-5
I...-_--------:-------------------~--_._-------
I
J
I
._.J
TABLE IX-2
SUMMARY OF FIXED AND VARIABLE ANNUAL CHARGES
'!:!ydroelectric Plant
......
Interest @ 6%
Sinking Fund @ 30 year s
Subtotal
Operation.Maintenanc e,and Administration
Subtotal
Surplu s
Total
Transmis sian System
Interest @ 6%
Sinking Fund @ 30 years
Subtotal
Operation,Maintenance,and Administration
Total
0,0600
0.0126
0.0726
0.0015
0.0741
Q.OOIO
0.0751
0.0600
0.0126
0.0726
0.0050
0.0776
IX ...·6
.-I
I
TABLE IX-3
COMPUTA TION OF COST TO POWER AND
ALLOCATION BY SERVICE AREA
IX-7
-------------------------------------------------------------1
1
I
-~factor than Fairbanks.To account for the value of this,project
costs have been attributed to power and energy on a 50-50 division,
and then allocated to the two service areas based on demand.The
resulting Anchorage-Cook Inlet revenue base at the power plant is
1 L 93 mills,while the Fairbanks base is 12.75 mills.Second,
the co sts of transmission to Anchorage-Cook Inlet and Fairbanks
are nearly equal,although the Anchorage-Cook Inlet Area draws
about three times as much energy from Susitna 1.The allocation
of transmission costs produces a charge of L 59 mills per kilo-
watt-hour for Anchorage-Cook Inlet,and 4.71 mills per kilowatt-
hour for Fairbanks.The resulting total cost of Susitna I power
at Anchorage would be 13.53 mills per kilowatt hour,while the
corresponding total for Fairbanks would be 17046 mills.
-
-
2.Cost of Thermal Power in the Anchorage-Cook Inlet and Fairbanks
Areas
The present average cost of power generated by Anchorage-Cook
Inlet and Fairbanks Area utilities has been estimated based on data
from Federal Power Commission and utility sources.1 Cost items
included are operation and maintenance of generating plants and
10ng-distance transmis sion,fuel cost,and allowances for depr ecia-
tion and administrative costs.
-
-
For Anchorage-Cook Inlet Area utilities,the resulting average
cost of energy generated in 1973 is estimated at 8.9 to 9.2 mills
per kilowatt-hour.Of this total cost,fuel alone averages about
40%.The corresponding fuel prices range from a low of approxi-
mately l6~per million Btu for natural gas at Beluga,to a high of
approximately 38¢per million Btu for natural gas delivered to
Anchorage.In 1974,the cost of natural gas delivered to Anchorage
was increased to 41¢per million Btu.In the last half of the 19,70 1 s,
it is expected that costs of Cook Inlet gas will continue to escalate,
reflecting the value of the gas in export markets.It is also con-
sidered probable that uniform Federal Power Commission price
regulation and usage restrictions will be applied to Alaskan natural
gas when a substantial level of exports to the lower 48 states de-'
ve10ps.At the present time,expansion plans for Anchorage-Cook
Inlet Area utilities rely solely on gas-fired capacity.
1 Federal Power Commis sion,II Statement of Income for Year,"
and 11 Electric Operation and Maintenance Expenses,"1973,
Chugach Electric Assn.,Inc ••Anchorage Municipal Light &
Power;Golden Valley Electric Assn.,Inc.,Annual Report,1973
IX-8
,.-
For Fairbanks,there is a wide spread between the 1973 costs of -,
the two area utilities;therefore the lower of the two systems'
average costs is taken as indicative.This was approximately 20.5
mills per kilowatt-hour.Of this,the fuel cost component was ap-
proximately 20%.The principal fuel used for power generation in
the Fairbanks Area is Healy coal,for which the most indicative
price is the present contract for mine-mouth delivery at Healy.
In 1973,this contract was 40¢per million Btu;however,this val-
ue has now been increased to 47¢per million Btu,with provision
for escalation following U.S.government indices to 1989.Fair-
banks utilities are planning to take power fronl a crude or residual
oil-fired gas turbine plant to be set up at a proposed refinery at
North Pole,beginning in 1977.followed by the po s sible addition of
coal-fired capacity at Healy in 1980.
A key factor in determining the value of power in the Anchorage-
Cook Inlet and Fairbanks Areas in the early 1980 s is the expected
market value of Alaska's petroleum products on the U.S.West
Coast.Recent data from petroleum industry sources indicate an I
expected long-term average price of $8 to $10 per barrel of crude
oil,with a similar value for residual fuel oil.This corresponds I
to a residual oil heating value of approximately $1.25 to $1.60 per
million Btu.It is probable that the cost of fuel products refined ,-,
in Alaska will roughly equal West Coast prices less the equivalent
of freight charges on crude oil.On this basis,the outlook for
residual oil prices in the Anchorage-Cook Inlet and Fairbanks
Areas in the early 1980s is approximately $7.50 to $9.50 per bar-
rel,or about $1.20 to $1.50 per million Btu.This estimate in
effect assumes that today's fuel price levels will still be current
in the early 1980s.
For natural gas,the West Coast nlarket value in the early 1980s
is also expected to be in the range of $1.25 to $1.50 per million
Btu.In the case of gas,the cost of liquefaction and shipping from
Alaska would be approximately 50¢per million Btu,resulting in a
market value in Alaska of about 75¢to $1.00 per million Btu.This
estimate is also consistent-with EI Paso Natural Gas Conlpanyl s
estimated transmis sion toll of approximately 65¢per thou sand
cubic feet (1,000 cubic feet =1 million Btu),from the North Slope
to Gravina Bay,plus wellhead prices of 10¢to 35¢per thousand
cubic feet.It is considered probable that Cook Inlet natural gas
prices will escalate to approximately this level,If the EI Paso
line is constructed,the Fairbanks Area may also be supplied with
IX-9------------------------_._-----,,_..___.,.._..__-,--'.
.....
natural gas.However,due to the smaller volume in the Fair-
banks Area and the need to install line taps and distribution facili-
ties at relatively high unit cost,it is estimated that gas will cost
about $1.00 per million Btu in Fairbanks.
If new sources of oil and gas are brought into production in South
Cook Inlet or the Gulf of Alaska,it is expected that their produc-
tion costs will be in the range of these prices,due to the cost of
new field development in the 1a st half of the 1970 s.
It is possible that coal will be among Alaska's cheaper fuels in
the 1980s.Under a current contract with a Fairbanks utility,
Healy coal is now available at 47¢per million Btu,subject to an
escalation agreement which could increase this price to approxi-
mately 73¢per million Btu by 1981 and to $L 00 per million Btu
by 1986.On the other hand,a California firm is now exploring
a coal deposit near Beluga;very tentatively,this deposit is
thought to be capable of producing at a mine-mouth cost of about
25¢per million Btu,but only in very large quantities.It is also
considered possible that the existing coal mines at Jonesville
could resume production at a cost of 50¢to 75¢per million Btu.
A major deterrent to use of coal as fuel will continue to be the
capital and operating costs of coal-fired steam power plants,
which are much higher than tho se of oil-and gas-·fired plants.
In addition,it is probable that environmental regulations on coal
mining and mine reclaiming practices could substantially increase
the selling price of coal from today's estimated levels.
In addition to these fuel cost indicators,it is estimated that capital
costs of fossil-fueled power plant and equipment,and operating
costs other than fuel,will escalate at an average of about 6%per
year through the early 1980 s.
With regard to possible alternate power sources other than hydro,
it is not expected that nuclear power will be competitive in Alaska
in the 1980 s due to the size of Alaskan power markets.the rapid-
ly escalating cost of nuclear plant and equipment,and potentially
serious thermal pollution problems in the Alaskan climate.While
Alaska may have attractive geothermal resources,it is believed
that several years of preliminary exploration,testing,and re-
search are required before these can be regarded as a practical
alternate power sourc e.
IX-IO
As a result of these cost indicators,estimates of power cost have
been prepared for new thermal generating systems commissioned
in 1981;these are indicated in Tables IX-4 and IX-5.These esti-
mates are considered roughly comparable to present power sys-
tem costs and also to Susitna proj ect power costs estimated for;
I
this report,These estimates include allowances for transmis-.
sion of thermal power from remote sites such as Beluga,Healy,
and North Pole.It is expected that most future thermal capacity
added to the Alaskan systems will be installed at such locations
both to save the cost of transporting fuel and to minimize thermal
pollution in urban areas.
1
I
-
The Anchorage-Cook Inlet Area is expected to have natural gas
available for fuel at approximately 75¢per million Btu,provided
that federal regulation does not restrict use of gas as utility fuel.
On this basis,the most economical method of thermal generation
in this area in the ear ly 1980 s is expected to be combined cycle
gas turbine base loading with open cycle peaking.The cost of gen-
eration produced by new plants of this type in the early 19805 is
expected to be 15.9 mills per kilowatt-hour,as shown in Table IX-2.
In the Fairbanks Area,it is considered possible that the EI Paso
transmis sion line will make natural ga s available at approximately
$1.00 per million Btu.Alternatively a spur from the Alaska-
Arctic Gas Co.line also could make gas available in Fairbanks,
although probably at higher cost.Provided that gas is available
at $1.00 per million Btu,gas turbine capacity similar to that used
in the Anchorage-Cook Inlet Area may be used in Fairbanks in the
early 1980 s with a resulting power cost of approximately 18.6 mills
per kilowatt-hour.If gas is not available in Fairbanks,a combina-
tion of coal-fired steam base loading and oil-fired open cycle gas
turbine peaking probably will be most economical,at a cost of
21,0 mills per kilowatt-hour.The Fairbanks Area is expected to
experience a smaller percentage increase in costs than Anchorage
because of sharp declines in costs of system overhead and reserves
as its relatively small base expands.
3.Comparison of Susitna I and Devil Canyon Project Costs
Estimated cost of Susitna I has been compared with that of the
Devil Canyon project based on data presented in the Alaska Power
Administration,"Devil Canyon Status Report,11 May 1974.For
IX-ll
I
L
-
TABLE IX-4
COST OF GAS TURBIN~POWER
EARLY 1980s
Combined Cycle:50 -75 thou sand kw
Gas-Fired Residual Oil-Fired
(Costs escalated to 1981 @ 6-1/2%)
Capital Cost,$/kw Continuous 1
Gas Turbine Unit 70%@ 180 124
Steam Turbine Unit 30%@ 470 141
Average Cost/Base kw 265
Allowance for Peaking Capacity,
gas turbine only @ 61.8%1£:
180 x .6 108
-
Subtotal
Allowance for Transmission
Total
Annual Capital Charges,$/kw/hr
6%-20 years =.0872
Cost to Power,mills/kwh @ 8,760
kwh/yr
Operation,Maintenance and Admin-
istrative Costs,Fixed and Variable
Fuel Cost
Gas @ 75~/million Btu x 10,900
Btu/kwh3
Residual Oil @ $1.20/million Btu
x 10,900 Btu/kwh
TOTAL p mills/kwh
Ga s @ $Jl /million Btu
372
150
522
45.52
5.2
2.5
8.2
409 2
150
559
48.74
5.6
2.5
13.1
21.2
IBased ;n 1974 costs as follows:gas turbine $125/kw,waste heat boiler
and steam turbine $350/kw;transmission $115,000/mi.I including
sub sta tion s.
2Residual oil-fired gas turbine plant estimated approximately 10%higher
than gas fir ed.
3Assumes combined cycle base loading at 10,000 Btu/kwh,with open
cycle peaking at 14,500 Btu/kwh.
4Probable least cost in Anchorage-Cook Inlet Area.
5probable least cost in Fairbanks,assuming availability of natural gas.
IX-12
TABLE IX-5
COST OF COAL-FIRED STEAM POWER WITH
GAS TURBINE PEAKING
EARLY 1980s
(Costs escalated to 1981 @ 6-1/2%)
[
I~\
Capital Cost,$/kw Continuous l
Steam Plant
Gas Turbine Pla.nt 180 x ,6
Subtotal
Allowance for Transmission
Total
Annual Capital Charges,$/kw/yr
6%-20 years =.0872
Cost to Power,mills/kwh @ 8,760 kwh/yr
Operating,Maintenance and Administrative
Costs,Fixed and Variable
Fuel Cost
Coal @ 80%x 25¢/million Btu x 9,000
Btu/kwh
Gas @ 20%x $1.OO/million Btu x
14 ~500 Btu/kwh
TOTAL,mills/kwh
Coal @ 50¢/million Btu
Coal @ 75¢/million Btu
Alternate Oil-Fired Peaking
Capital Cost Adjusb:nent
Gas Turbine Plant 108 x .1 x .0872 -+
8,760
Fuel Cost
Residual Oil @ 20%x 1.20/million Btu
x 14,500 Btu/kwh
TOTAL,mills/kwh
Coal @ SO¢/rnillion Btu
Coal @ 75¢!million Btu
600
108
708
150
858
74.82
8.5
3.5
1.8
2.9
16.7
18.5
20.3
. 1
3.5
17.4
19.2
21.02
I
I.~
lBased on 1974 co sts as follows:coal-fir ed steam plant $450/kw;gas
turbine $125/kwh;transmission $115,OOO/mi.,including substations.
2Probable least cost in Fairbanks if natural gas is not available.
IX-l j
_._-~-_...__.._----_._._.•.•._---
),J)r)1'1,1
)
APPENDIX TABLE 6 (Cant)
)11.r
)SUSITNA'RIVER D~~1E B _
I
____'/4 ,1/4.Sec.__,__R __,.8 c.M
LoomON _ACTIVITY
SOURCE OF RECORD Genera~ed:..-Qq.Q.._~._9_..23.1 .,
S .t R·B·1 t 000
RUNUFf OF.us~na ,~ver as~n STREAM FLOW sur,~rv1/~RY UNIL_acre";'feet AREA --5J.Q9_.S:l """'.
I~b'\SON r-'OCT.I NOV.I DEC.JAN FEB.~A~I~~;;;-r-~;,{,(I ,):)NE JULY AUG':'~LPT -~~:I:'-;-:-'!.1--.~-t
1970 I 178.85 67.31 49.591 47.18 I 39.71 I 44.411 59.84 \651.511032.48 1296.8811~43.271 505~35i 5116.38 :
---..-...j .-_..._-_.....-.--......._...._-......----.--..._._..-...._..J ....-.--_.-_.._-.•_.-._-.-..'''''-'·•....·-----t··..--·-·--t·-------·....I 1971 I 302.67 I 188.71 131.09
1 82.54 I 53.551 54.38 !59.92 1214.41:1824.76 1371.36 1826.62 800.10 i .6910 .{1 i
,.I I
-'--#---'"I i ---!I --t·---r -1---'+-----1------i---·-·}._J
,,'I I!I ;
~'-'-,~Q2.88.Il!l,lot 63.841 62.47{74..7Bj _76B.sa.~6 Q~5J 7Br_hl!6639-':~
.,•.~-'--'.-.----.------+----~------l----I--·---1------j-----I---·--L-----1----~-----I----1
.r-Annual-..--5.....-0_-.......,g=J.1 L__~.2...j .w....+1.0 +..lL•.9._I._.._L..l.....l._..~'7 I 1'),f\I -19...3-.t--11 .•5 -1-.lQO%__~
,i !111 I~I 'i ',I I J ;!I I .N L':'.r----j·'''''-,---1-----r--'-1---r-'H 1-.-.-·--·--1---·1---'-1---1--1----,--------·--·~;
!I j'Iii I i ii I !.t=-1·----.-------,,··-----+-.-[-j----+--+----+----!----+-----j
I --'1----1---+----r-------1--·,-..-----r----r--~+--Ii------t----·..·------.if-------[f-,-c--I 1-----~-.r---.---!------i'----t----t-----!---.-;.;-~.-_.------'1
.t I---~·-..·--T----H .'I----r '---.-----t---t I-I t---------i
.- ----I i
i I lr---------,~!I _.~=i =---ri~--ti-..._.'11
.'1-".
I -"-_....._--..I
I j~-'--[-'--""'-'---,-:'I ..._j
i .)+1 __.LI
.__._...L.-----..--·.l.-.-··....·+--------T---··~J·------...--------I
}---.'-_.---------=.~--].~J -~--+-------i--~r----l-I---~__=-__J
l .---'--'''----J.I ..I I -l ...t_·'·--=__.L '.__.....L ._..-__........-l..-~__.
APPENDIX TABLE 6
STREAM FLOW SUMMARY
,
ACTIVITY
SOURCE O;~~COR;G~~e;;.te-d:-QGc-~-O-~-931 \1,000 --------
UNIT acre-feet .AREA _576~Sq Mi\.>s
-,'I 1 1 1 1)l11lclI11
..ac.Hlc"bJI'I'NA RIVER IlAMSITE B-----------------------
.__l/4.1/4,Sec.__T__R_-.•__._SE.M
'RUNOFF OF Susitna River Basin
:SEASON I OCT.I NOV.I DEC_I JAN.r FEB.I MAR T APR.I MAY I JUNE I JULY I AUG I SEPT I TOTAL I.~.362.62.~43.~0 _82.36 I 58.8~!40.721 41:.571 48.201 658.961~085.5511294.o91il37.681 459.9~1 5413.57 1
~~95~220.28 72.02 62.97 54.96
'.1952 i 318.871 152.03 108.74 I 91.59
1953 469.50 1 193.741 97.29 62.97,,
..1--1954 320.73 116.381 85.87 74.42 1 51.71 .44.65 6-8.4;-/989.6;1398.36 1165.61 1494.25 715.47 6525.52 -lh~955 I 307.42 ~2.87~J:7.~2 ~02 .69 72.39 62.97 __~6.47._533.46 ~654.39 ~577.il ~4 73.77 791.54_.~9~-=--~o....
~~9~J_28~4()1 ~05 .30 J 74.42--l 56:~0 I.5~.95 ~53.8~1 52 .63!'=Oil.crr ~847•~o ~780.07 ~403.95~~5 •721.7735 .~
,~95~1_332.31 168.981122.6~L_97.29[77.56 68.7~_66.47 j 787.44 ~67~.~4 1334.12 1175.85 ~096.~2r 699~.25
~58 '.470.06 219.06 Ie 186.85 112.471 67.59 65.•74 84.9~_L 738.19 1423.50 1309.92 12 90 .37,418.30r_~~_~_~~~~
1959 275.39 119.0~86.60 I 82.92 1 67.59 56.10 69.25 1 915.17 1292.23 1430.95 1784.7~937.52 7117.53 I
I·1960 375.38 157.90 1 125.96 105.671 77.74 68.51 72.02 903.35 860.52 1315.50 1350.88 1135.82 6549.251rI1------.------------.-'-.----f---.-_"...1
!1961 446.14
1
166.181 154.17 .140.3°1 90.67 103;62 146.82 994.31 1632.04 1406.74 1265.23 740.89 7287.11 l
L=~21 33B.7d~49.6~T 120.l~I ..~08.7{~.~~~.~~~~4.22 ~!!0.69,=397.32 _~480~~S --=31,8~~L880.2~~7795_~~~1
!~963 I 384.88 ~55.il~4.51g.59r 77.56 .57.251._~5.98 ,=°89.27 ~440.26 ~969.06 ,=355.54 682.42 7463,:,4:!
1964 369.1~124.661 85.49 60.011 51.75 40.~4l.27 246.53 2802.31 1313.6~941.24 530.2C 6607.06~
1965 360.11 155.111 ~9.30 54.96 44.47 51.52/75.35 743.40 1424.43 1593.87 1208.44 1071.5t 6852.54
1966---4~115.9~1 93.3~"'"80.~4 67.22 ._74.-421~=98.~~~~~5-2.~t 1825.69 1136.75-1249._~..651.1L ~-35~.9~J
~967 I 238.31<88.64
1
85.87 I 85.87 72.39 68.7~~64.63 886.22,~634.84 ~534.25,~867.59 934.72 7562.~o I
,..i96st·---;80.5ic-~30.34j1l7-:59 113.4o ~01.76 ~0B.74 i05 :&;-926.OJ ~M .49 ~5~2.8f983 .1:4>-488;4c --6616.~71
,19691218.7c 90.301 50.51 41.46 37.40 46.7;;:83.65 632.31.858.85 921.7 508.3:282.1(3772.32 j
R~NOFV of_SQ$ITNA RIVER BASIN
)1111
ACTIVITY ...,......__-,-_
SOURCE OF RECORD USGS,__._
1 9 000
UNIT -ac~e-feet AREA 4140 $'.~.~1'f'5
11}..J
)1
APPENDIX'TABLE 5
STREAM FLOW SUMMARY
1111~}
LOCATION SUSTTNA RIVER.C~j.,__-1__
___1/4.1/4 j Sec.__T__R __•__B &M
I-_~EAS'JN I OCT.I NOV.I DEC,'JAN FEB MAR I .WR !M/\Y JUNE JULY AUG S~PT.TOif'L'1
G96_2 .~6.~112.,90 .Jl8,}!!._~,08 __61.09~.6.J,.49__II .~~.L§ll.2Q 1822.go J21.33,Q9 _;JJ.05.00 626 .60 6~8.00I
1'1 ~I 1963 __26.6.00 130.90 86.08 61.49 47.21 46.7?-t._~_~4 t-697.20 892.60 ,1401.00~e.00 .546.60 5337.00 ir-:;;;-,236.60 _77.36 ,53-95 _39.59 33.70 '._26.~.~_J!7,..§7.1_.172.60 .2060.:..q()~048.00.307:50 _31.a~14.a02,()~.J
t
l 1~L192.70_..E3 •7()G~·65 46.73 37.77!~,~+.6Z·.~6 1.542 ,5.0.9'r.7.g()112~00 I 826.40 [768.10~.4799.00_)
1966 ,191.60 59.50!46.12 43.04 36.10 39.97 1 52.07i 269.801101.00 751.10 I 779.501 388.10 13757.10 I
11967 ~142.80 46.41 04.27 41.81.'--25.54 i .1.~3 4 .'le:>..55 j5.8~.2~tll~.00~~8.00 j1l8_0.0~1 ~ll.~i 4954:.~.!1.19~81~~·60 88.66 ~~.~~?-1--_I?'74.69.~~L73._._.1..?-....t.--.-_.1.2•.I9 j.._?§2.'~'.~~i ~160.9E+1075..00 -t..i72 .4{]21.?_O.~445CL~tl..._~.1969~48.00 63.27 i 37.98 L:31.24..I 26.94 1_33.:70 I.__59.~tl-459.40 ~..50 i 830 ~.70t_3~0.9~J_~031.00 -!
1970 1100.70 48.50 I 33.40f;6.B61 23.641 28.48_~_:52.76 __466.10 589~54.70 I 757.80 310.10 13293.00 i~;-r~~~.50 91.041-"~4.46 r-;-;;l--;-.;r-;8.~8 I ~1.46!-~~;7011307 .00 11115.0~j 1396.0J 583:10 !~40.00 -~
1972 I.~49.50 122.00 I 84.30_~.~__53.~'.54 .1~]'.__5.2 .J,l:1_596 .OO~1l~0.~O~1026.00J~60.60 I 560.70fY.(Jl":..~.~----+-I I L--t-------------J-----l I.-----L-'.I
F'I.--! .
1Avers&e IB8.78..ID:.30~~0 I ~1.20,_
,I Ii.II I I I I !
1 'J I IJ I !I J I'l1:_4'11.9+~4_1.1 0.9 _0.:1:~~_I~lo~oi--2~~~j 23.1 1
19
.
6
lQ.3 _laoS _.~
----j'---·..----r---'--··..-r------~--.·-----l.------------1----.--.-;--.----'-----l~---.f----+----L +-------rl
---~i------1
I J L I !I '-1 I !L--..__.._~.._.....__....__.--'-..~__h _.~J
______1/4 ,.__1/4 ,Sec.__T R ,9£.M
R:i:,GfF OF SUSITNA...RI.'W.~Bw;AS!3Wolw.N1--._
APPENDIX TABLE 4 (Cont)
STREAM FLOW SUMMARY
}1111
ACTIVITY _
SOURCE OF RECORD .\l§.®...____._
1,000 -
UNIT _acr~_-f~et _AREA __-.-61..60 . _$q Mllo's
11)11\1 1 1
)SUSITNA..RIVER~lO~/\TiON _._
f :u..sC:J 1 OCT.l~NOV.DEC.JAN..1 FEB_I M,'\R I i.r-R.MAY JUNE JULY t.UG SEPT.-lOTALI,.--wi
!!,
!1970 I 192.10 72.30 53.26 50.68 42.65 47.70 64.27 699.80 1109.60 l393.00 1228.00 542.80 5496.00
~-,-------._.
l~2.~_~25.10 202.70 -140.80 88.66 57.52 58.41 64.36 230.30 1960.00 1473.00 1962.00 829.40 ~~~~.OO_
_!------4-----._.--..---.--_...a I I --_.-I
I-
I------._---j-_._-_.-.--...__.-
_20.8 20.0 r~.1~~
1167·22 1520.161 1334~~775.86 ,712 5,0.0 ':1Ii'_18-L1.2:~
-I
lAverage L i '1'·I I .1 1 I I I I --+r962-7~i 333.,86~40.33 r 03 .tg :--57 .31.t_·11 .4l.1J-.43 1-.aCl....~4 j .1I.2·.2.5-r.J.~~5.1\!507 ..10+~21.D~_+706~.QQ-I
~9~~~r~::;j-~.-;id __~.5f-u~:2'!--l:Ju 1.0 -1 -l~j-~O.;-~~.:'2L;'~;';---10.;J '19~"1'
!!I It·!I.~~;~~'fr J24'98}~.~j=~Q~~~~__9_0~13_jl~68.5t67~~r~O.D~~;5.Q~169~~~~494'~+13~'J~'~~;~L 7l3~;_~
t~=-5.01 2.J-~.5j-.-1.3--'1-_1.0 1-0'9~=Ll~.6 2~;--21~0 I 1;~':~-l10;;~'J
i!f I ,;I ill I j ~..-L .
)1 J 1 ,.1 1 1 1 'J 1 1 l·"c,1 1
GOLD CREEK )ACTIVITY -_._------------_.-
6160 _.,_SQ Miles
SOURCE OF RECORD USGS1,000',---,
l1NIT acre-feet ,AREA
APPENDIX TA BLE 4..
STREAM FLOW SUMMARYi-lut~C;Ff'OF_Susit~River ~:=s:.::i:::n=--_
'"T"J )
'''''
LOCA,ION _)suSITNA RIVER,
,,1/4.1/4,Sec T R •8 &M
TOTALSEPT.AUGJULYJUNEMAYAPR.MAR.
45.50
I
54.11
FEB,
45.54
57·52
I I 43 •741_44.6~_.~~1 707.80 11166.0°11390.09 1222.001 494.00 I 5815.00 I
i ,r i r t t ,I i 1 i •..-,
r-SEASON I OCT.~Nev.r DEC.I JAN.
I .
U950 L389.50 ~153.701 88:46 1 63.17
!19;-1236.60.77.361 67.641 59.03
:--1952 342,,50!163,,30f 1~6.80 I 98 ..38 54.74 333.20 1926.001 1622.0q 1286.001 861.60 I 6917.00
,-r------4-----+---.---~,
i 1953 I 504.30 208.101 104~7 .64 45.54 50.42 96.10 1185.00 1626.00 1242.OC 1267.00 908.80 7305.00 I
I 1954 344.50 125.00r-;2..23j 7;:;;.55.54 4~.96 ·~~.4;'1063.00 1502.00 1252.0C 1605.001 768.50 7009.00 i
i 1955 330.20 164.201 125.80 110.30 77.75 6_7,,_64._.!1_._40 573.00 1777.00 1694"oc 1583.00 .8_5_0.2_0.__._74_24_'~~j
1_1956 _304.40 113.1~;__79:~~~.26 t-~57 .80 ~6.5~:~.~1984.00 1912.0(1508.00 1091.00 8309.00
i 1957 357.00 181.501 131.70 104.50 r 83.31 73.79 n.4oj 845.80 1795.00 1433.0(1263.00 1178.00 ..75{8.00
j ~9~8 _I 504.90'23;:;}200.7~-12~.80 -;;.60 ---;;-:6~--91.;4 792.90 1529.00 1407.0<1386.00 449.30 ~~60.ooJ
I 1959 295.80 I 127.90
1
93.02 89.06 72.60 60.26 74.381 983.ob 1388.00 1537.0(1917.00 1007.00 761J.5.00
l1960 I 403.20 L169 .60
T
135 'ffi 1],).50 8~:~_73.~__:77 .3~i 970.30'92~.3l1413.a<j 1451 •0 Oj 1220 .00 1__2~35.00,
I ~479 .20 I 178 .50 165.60 150.70 97 .39j 111.30 157.70h068 .00 1753.00 1511.or-1359.ad 795.801 7827.00
•i 1962 ~_363 .80 L:-~.701~129 '~I ~116.80 ~~~.31 i 86 .08__:':1.~ol_774.10 12575 .00 --=~90.:0 945.50 I 8:~4.~-;
L!~_~~3.,4o_1 __~6 :61 123 '~1 ya .3~1 83.31 61.49 __~9.391117.:'.·00 1547.00 _2115 •0 1~~_73~.~~__8017.00 I
I 1964 I 396.50 I 133.901 9L831 64.46 1 55.58 43.851 44.331 264.8013010000 1411.0 1011.0 569.50 7097.00 I
I.-~96;r;B6.80 ~166.601 74.44,_59.:~~L_47.761~~~{_~O.93,__.298 .50 _,1530.00 1712.00 _1298.OC 1151.00r-7~,2.00i-1966 J 44~----=:4,5C 100 .30 ~.:08 72.20I~~~J _::'~60_593.~~_1961~1221.0 1342 .()(_699.40 _6~29 .~
~196!__-l.~56.00 95.21 92.23,92.23_77.75 73.791 69.42 951.90 1756.oc 1648.0 2006.oc 1004.00 ...~122_~00
__1968_1~01.30 140.0(126.30'121.80 109 .30 ~--ll3.70 994.70 1877 .O(1625.0 1056.0<524.60 ._7106.00
I 1969 I 235.00 96.95 54.25 44.53 40.17 50.18 89.85 679.2Q 922.5C 990.1)546 0 0c 303.10 4052.00
this purpose,Devil Canyon cost data based on January 1974 prices
have been escalated by 6%to a level comparable with the June 1974
estimating base used for Susitna 1.The value of interest during
construction has also been adjusted to repr esent the differing in-
terest rates used under each set of criteria.As shown in Table
IX-6,Susitna I project costs in mills per kilowatt-hour of energy
sold equal 75.4%of the comparable costs for Devil Canyon.
------------'---------------,~---_..,
I----~
TABLE IX-6
COMPARISON OF PROJECT COSTS
SUSITNA I V.DEVIL CANYON
Economic Financial Susitna 1
of dollars ($OOOL except as noted
Federal
Susitna 1
Economic Financial
thousands
C "t "1rlerla
Devil Canyon
Kaiser Criteria2
Devil
Canyon
Total Capital Investment
Annual Capital Charges
Rate
Amount
649,300
.0689
44,737
633,300
.0601
38,061
742,000
.0689
51,123
722.900
.0601
43,446
638.100
.0726
46,326
729,000
.0726
52,925
Annual Operating Costs
Rate
Amount
Total Annual Costs
Energy Sales,kwh (millions)
Cost in Mills/kwh
Susitna 1 %Devil Canyon
.0015 .0015 .0015 .0015 .0029 3 .0029
974 950
1,113 1,084 1,846 2,114
45,711 39,0 II 52,236 44,530 48,172 55,039
3,330 3,330 2,866 2,866 3,330 2,866
13.75 11.72 18.23 15.54.14.47 19.20
75.4 75.4 75.4
---{'-,,-
r-<
X
VI
IFederal criteria specify the following interest and amortization criteria:
Economic analysis,interest 6.875%,amortization 100 years.
Financial analysis,interest 5.625%,amortization 50 years.
2Kaiser criteria are interest 6%,amortization 30 year s.
3Includes allowances for sinking fund and cash surplus.,
\
«----'\,
X.ENERGY -INTENSIVE INDUSTRIES
Prior to the preparation of this report,it was believed that the addition
of a large industrial energy user to the Anchorage-Cook Inlet or Fair-
banks Areas would be necessary if Susitna I were to be developed on the
largest and correspondingly most economical initial scale.
Accordingly,the Henry J.Kaiser Company obtained expressions of in-
terest in purchasing Alaskan hydropower from Kaiser Aluminum &
Chemical Corporation and other primary aluminum manufacturers.
These firms were interested in obtaining approximately 300 I 9Q,Q co:gJ.\.E:
!lOPS 'd 1 g w 8:bhs of pOWer,approximately 2,600 million kilowatt-hours~<per
year,at an average cost of less than 10 mills per kilowatt-hour.1£such
a power source were made available in Alaska,it is probable that an
aluminum reduction plant could be located in the state.
As this report materialized,three main factors became clear.First,
it was evident that reasonable and conservative forecasts of utility load
growth in the Anchorage·-Cook Inlet and Fairbanks Areas would be sub-
stantially higher than previously anticipated.Second,the optimum or
most economical capacity of Susitna I was determined to be 385,000 con-
tinuous kilowatts,instead of 450-500,000 as originally considered prob-
able.Third,due to the substantial and probably non-recurring inflation
of the first half of 1974,the cost base for Susitna I escalated to an un-
expected high level.
As a result"it has been concluded that lltility demand in the Anchorage-
Cook Inlet and Fairbanks Areas is capable of providing a sufficient
revenue base for Susitna I and that mor,eover,the full capacity of
Susitna I can be utilized within five years of normal utility load growth.
The estimated cost of Susitna I power is estimated to be less that that
of alternative methods of utility generation in the early 1980 I s;however,
it is higher than the ceiling which an aluminum manufacturer would
consider at the present time.
X-I
.....
XI.ENVIRONMENTAL CONSIDERATIONS
A.INTRODUCTION
The environmental impact of land inunda tion in the upper Susitna
River Basin has been evaluated by a number of governmental agen-
cies;namely,the Fish and Wildlife Service,the Bureau of Mines,
the Bureau of Land Management in respect of forestry resources,
and National Park Service,and the Corps of Engineers.Various of
these reports ar e contained in the Devil Canyon report of 1960 and
a further listing of reports and additional comments ar e made in the
Devil Canyon Status Report of May 1974 .
While some recommendations have been made in connection with
further studies,it has been generally concluded that the reservoirs
created by the construction of dams at Denali and Devil Canyon
would have r ela tively small impact on the environment considering
the size of the project,It has been recommended that the future
Vee reservoir should not be any higher than conceived in the overall
development plan lest it affect the sport fishing resource in the
Tyone Basin.
B.CANYON SECTION OF THE RIVER
None of the available reports raise any serious questions on the en-
vironmental impact of lands to be flooded within the confines of the
canyon stretch of the river which extends approximately to the mouth
of the Oshetna River.The steep canyon walls encountered in much
of this stretch of the river are not conducive to significant wildlife
habitation and the loss of wildlife habitat in the canyon would be ex-
pected to be small.There is no evidence of anadromous fish in the
canyon,due presumably to high water velocities,and at present
sport fishing is virtually nonexistent.Improved accessibility with
roads and reservoirs will result in increased hunting and fishing,
but both will be mitigated to some extent by the fluctuation of reser-
voir levels.While reservoirs in the canyon will flood some forest
lands,these areas are generally inaccessible without project devel-
opment.There are no known mineral resources within the canyon
section of the river.
XI-l
-
C.DENALI AND VEE
The Denali reservoir.as projected in the Devil Canyon Status Re-
port of 1974,would inundate an area of 54,000 acres and Vee,with
a reservoir elevation of 2,355 feet would inundate an area of 17.000
acres,Inundation of these areas is not expected to adversely affect
fishing.
The most significant im.pact of inundation of these areas would be the
destruction of the moose habitat,largely in the Denali area,and the
loss of rangelands for caribou,It is anticipated that the moose popu-
lation of flooded areas must be relocated,as it is considered unlikely
that the surrounding area can support the displaced animals.The
loss of caribou rangeland is not considered significant;inundation of
the land would not seriou sly affect rnovement of caribou to other
areas.The effect of inundation on the habitat of certain other wild-
life requires more investigation;however,waterfowl would appear
to be little affected.Of the two areas.Denali and Vee,the most ex-
treme impacts of inundation are at Denali,the necessity of which is
largely eliminated by the alternate development scheme presented
herein.Improved ace es sibility would increase game take in both
areas.Mineral and forest resources in the area have not been fully
evaluated,although it would appear that the loss of marketable timber
through inundation would not be significant.
D.THE TRANSMISSION SYS TEMS
The mo st significant impact of the transmis sian system would be the
appearance of towers and lines which would intrude on the natural
scene.Wildlife would be little affected,However,detailed line
routing studies win have to be made to minimize the impact of the
transmission systems on both natural scenic beauty and wildlife.
E.SUMMARY
It is apparent that inundation of the canyon section of the river would
have little effect upon the environment.The inundation of areas up-
stream of Vee and Denali would have greater but still moderate im-
pacts.Any development which includes Denali will have to ju stify in-
creased environmental impacts over development restricted to the
canyon section,and development which can economically exclude
Denali would be pr eferable.
XI-2
l
i
I
Development of the river upstream of Susitna I would provide for a
re servoir inundating approximately the same area a s would the Ve.e
Canyon project proposed by the U.S.B.R.As noted,the impact on
the environment by the Vee project reservoir would appear to be
considerably less than the impact created by the Denali reservoir.
While detailed studies would be required fo~the lands to be inundated
by the reservoir in or near Vee Canyon,the overall impact of the
Kaiser concept would be reduced to the extent that Denali reservoir.
is eliminated.
The Kaiser concept of initial development of the hyd",oelectric poten-
tial of the upper Susitna River,first-stage project,designated as
Susitna I,proposes a project which l.imits the inundation of land to'
about 24,000 acres in the canyon section of the river.By eliminating ~,
the Denali dam and reservoir,which alone would inundate 54,000 acres
(61,550 acres with Devil Cany<:m),the impact upon the environment
for first-stage development of the riv~~r resource is considerably re-
duced.The depth and cost of further detailed envirdnmental studie s
for initial development would be reduced;approval for implementation
of the project with due consideration for environmental impact would
be more easily attained.
..-
-
-
To accurately assess environmental impacts from development.of
the hydrbelectric potential of the uppe:r Susitna River,it will be nec-
essary'not only to review all presently available data,but also to
complete such studies as may significantly influence final im.pact
evaluations.Such studies would include benefits to recreation and
asseSiSffient of impact on the environment of alternative m.eans of
generating electric power.
Full and open evaluation of the environmental impact of Susitna River
development must be made in the earliest stages of pl:oject planning
so that once committed,hydroelectric development can proceed
without delay due to environmental problems.
XI-3
L,--'--'-_-'--.,.._.............._".
-
-
-
-
-
-
-
-
-
-
-
XII.FUTURE DEVELOPMENT
A.INTRODUCTION
The Susitna I hydroelectric project recommended by the Henry J.
Kaiser Company as the initial step in development of the upper
Susitna River also allows for two future projects which may be de-
signed to utilize the river's full hydroelectric potential.These proj-
ects are located both downstream and upstream of Susitna I,as out-
lined in this section.
B,DOWNSTREAM DEVELOPMENT:SUSITNA II
The degree of river regulation resulting from Susitna I would facil-
itate the economical construction of a run-of-the-river hydroelec-
tric plant downstream.Approximately 110 feet of head could be de-
veloped by the construction of a low dam at the Devil Canyon site.
Downstream of Portage Creek,three miles below Devil Canyon,ap-
proximately 155 feet of head can be developed,and the inflow from
Portage Creek can be captured,adding approximately 4%to total
runoff.
Either the Devil Canyon or Po:rtage Creek site is technically suit-
able for hydroelectric project construction.The Portage Creek site
would require a longer dam than the Devil Canyon site,but it en-
ables construction of a more economical surface powerhouse and an
easier overall construction program than would be possible within
the narrow confines of Devil Canyon.The Portage Creek site is
well ~suited for a rockfill dam,and the native greywacke would be
an excellent construction material.
Construction of Susitna II would be simplified by the river control af-
forded by Susitna 1 9 the primary site access road would have been
built for Su sitna I.and the proj ect"s power output could be carried
by the Susitna I transmis sion system.If constructed on the Portage
Creek site,Susitna II could generate an estimated 785 million kilo-
watt-hours of energy,and would have an installed capacity of 163,000
kilowatts,at a 55%plant factor.It is estimated that Susitna II would
cost on the order of $500 to $600 per installed kilowatt.two-thirds
or less the cost of Susitna I.including transmission.Additiona.l
studies are required to determine the general characteristics of
Susitna 11 and its impact on overall system operation and cost of
power.
I-~__,_------------_._----XII~~J
Susitna III could be located near the upstream end of the reservoir
formed by Susitna I,in the canyon section between theWatana and
Vee sites proposed by U.S.B.R.Detailed studies would be required
to finalize location of Susitna III and to establish its most economical
project size.
-
-
.....
,.------------------------------'----
C.UPSTREAM DEVELOPMENT:SUSITNA III
I ,
-
-
.-
-
-
In concept,Susitna III would impound a reservoir somewhat larger
than that visualized at Vee by U.S.B.R.;however,its maximum
normal reservoir elevation would be 2,355 feet,the same level in-
dicated for the Vee project.The Susitna III dam would be approxi-
mately 600 feet high over the riverbed.
Assuming that the Susitna III would be operated in the same manner
proposed for Susitna I,but as an independent facility,its installed
capacity would be about 380,000 kilowatts on an annual plant fador
of 55%.Under these conditions,the annual energy output of Susitna III
would be approximately 1,840 million kilowatt-hours.However,pre-
liminary study indicates that river regulation provided by Susitna III
would increase the annual energy generated by Susitna I'approxi-
mately 9%,~from 3,372 million kilowatt-hours to 3;679 million kilo-
watt-hours;therefore the combined annual generation of Susitna I
and Susitna III would total 5,519 million kilowatt-hours.
It is expected that in practice,operation of theSusitna I and Susitna
III reservoirs and power plants would be integrated for greater effi-
ciency.Under such an integrated operation,with an overall annual
load factor of 550/0,the total installed capacity of the two sites would
be 1,145,000 kilowatts.With 700,000 kilowatts installed at Susitna
I,the installed capacity at Susitna III would be 445,000 kilowatts,
and the annual plant factor at Susitna.III would be 47.2%.Further
detailed studies would be necessary to determine the most efficient
means of integrated operation,as well as the optimum installed ca-
pacity for Susitna Ill.
D.THE ULTIMATE DEVELOPMENT
Ultimate development of the three projects,Susitna I,II,and III,
would provide total installed capacity of about 1,308,000 kilowatts,
with annual energy generation of about 6,309 million kilowatt-hours.
Fully integrated operation-of the three facilities could result in a
still higher total capability;however,this requires further detailed
study.
XII-l
l"'!'f-
-
/~.E.COMPARISON WITH THE U.S.B.R.SCHEME
-
-
-
-
-
-
-
.,...
~....
The U.S.B.R.scheme for ultimate development of the upper Susitna
River includes dams at Devil Canyon,Watana,Vee,and Denali,
with power plants at the first three sites.Installed capacity under
this scheme would be 1,372,000 kilowatts,and annual energy gen-
eration would be 7,000 million kilowaU-hours.
Both the U.S.B.R.scheme and Kaiser r s alternate concept would re-
quire detailed study to justify subsequent stages of development and
to establish the economic size of future projects.It is considered,
however,that the Susitna I,II,and III projects,as proposed by
Kaiser,are potentially more econox::nical than the major projects at
Devil Canyon,Watana,Vee,and Denali sites proposed by U.S.B.R.
The total installed capacity outlined by U.S.B.R.is approximately
5%greater than projected by Kaiser,while annual energy generation
indicated by U.S.B.R.is 11%greater than Kaiser's.This is be-
cause the ultimate development outlined by Kaiser excludes Denali
dam and reservoir for economic,and environmental reasons.
If Denali were added to Kaiser 1 s alternate concept,a rela.tively small
dam and reservoir on that site could provide a sufficient increase in
river regulation to raise the combined outputs of Susitna I,II,and III
to equaLthe capability oJ the U.S.B.R.scheme.Alternatively,due
to the storage provided by Susitna I,Kaiser I s concept would allow
the Denali project to be designed to release its stored water on a
year-round basis,and a power plant could be installed at Denali,
further increasing total energy generated by the alternate system.
This is not possible under the U.S.B.R.scheme,in which the Denali
reservoir provides most storage for the system as a whole;because
of this,it must in most years be fully drawn down in an eight-month
annual period of operation,and would not furnish sufficient average
head to justify a power plant.
Although Kaiser's alternate concept tentatively excludes Denali,it
would still be possible to develop thi.s project following Susitna I,II,
and III,pending more favorable conclusions on its technical and eco-
nomic feasibility,and especially its environmental impacts.
XU-3
._~--------.~~,.,-------------_._---I------
~))')
f
APPENDIX TABLE I
RECORDS AND FORECASTS OF
ANCHORAGE-COOK INLET AND FP.IRBANKS AREA
UTILITIES
1968-1990
AML&P Total GVEA FMUS
Peak
Load
(thousand kw)
Total
Net
Energy
(million kwh)
Peak
Load
(thousand kw)
Net
Energy
(million kwh)
Peak
Load
(thousand kw)
Net
Energy
(million kwh)
Peak
Load
(thousand kw)
Net
Energy
(million kwh)
Peak
Load l
(thousand kw)
Net
Energy
(million kwh)
CEA,HEA,MEA
Net Peak
Energy Load
(million kwh)(thousand kw)Year
1968
1969
1970
1971
1912
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
IlJ85
1986
Il~87
1988
1989
1'90
674.0 152.0
789.7 175.I
n5.3 201.8
1,084.I 232.4
1,270.4 267.9
1,488.6 308.8
1,662.0 344.8
1,865.5 385.0
2,073.4 429.0
2,316.3 479.9
2,587.7 536.0
425
455
495
545
600
655
725
800
875
965
1,050
1,175
43
48
56
64
68
73
81
91
101
113
125
138
1,350
1,539
1,765
2,034
2,262
2,521
2,798
3,116
3,463
UO
248 221 49.4 95 20.3 316 69.7
283 258 57.I 103 21.9 361 79.0
323 302 66.2 110 23.7 412 89.9
369 352 76.6 119 25.5 471 102.I
422 41Z 88.7 128 27.6 540 116.3
470 476 100.5 138 29.8 614 130.3
523 527 111.8 149 32.I 676 143.9
583 124.3 160 34.6 743 158.9
646 138.2 173 37.2 819 175.4
714 153.7 187 40.0 901 193.7
793 170.9 199 43.1 992 214.0
877 190.1 216 "':to."t 1,093 236.5
970 211.4 233 49.9 1,203 261.3
1,076 235.I 249 53.8 1,325 288.9
1,ln 261.4 267 57.8 1,459 319.2
I Adjusted !rom fiscal to calendar years
Source:Chugach Electric Assn.,Inc.(CEA),includes Homer Electric Aun.,Inc.(HEA),and Matsnuska Electric Assn.,Inc.(MEA),
Anchorage Municipal Light l.Power Dept.(AML&.P),Golden Valley Electric As sn.•Inc.(GVEA),Fairbanks Municipal
Utilities System (FMUS).
-
-
APPENDIX TABLE ;:
ALASKA POWER ADMINISTRATION
"UTILITY LOAD ESTIMATE EXTENDED TO 1990"
I
I
Generation
1972 1980
Projected Requirements
1990
71.9 310.I 123.0 658.0 314.0 1,680.0
123.5 600.0 360.0 1,800.0 1,065.0 5,370.0
(16.5)(85.I)(36.5)(190.01 (90.0)(490.0)
(4.7)(22.I)(7.9)(37.6)(14.9)(71.I)
0.8)(3.4)1.6)6.8)3.5)16.I)
Not Available 5.2)27.9)8.0)45,0)
Not Available (2.I)(8.7)(3.0)(12.3)
~73.9 ~-225.0 181.0 850.0
211.3 984.0 537.0 2,683.0 1,560.0 7,900.0
1.3 5.8 2.3 10.I 4,6 20.2
1.2 5.4 3.2 14.0 5,2 22,8
7.6 33.4 13.4 61.9 22.I 102.9
0.2 0.8 0.3 1.2 0.4 1,6
1.5 6.4 4.2 18.3 6.9 30.0
0.5 1.2 ~-1.8 I.I 2.9
223.6 1,037.0 561.I 2,790.3 1,600.3 8,080.4Total,Southcentral Region
-
.....
-
-
-
Location and Utility Symbol
Southcentral l
City of Anchorage (AML&P)
Chugach (CEA)
Include:
Homer (HEA)
Kenai (HEA)
Seldovia-Port Grah...m
(HEA)
Seward (SL&P)
Tyonek
Palmer-Talkeetna (MEA)
Subtotal,Anchorage-Cook
Inlet Area
Cordova (CPU)2
Glennallen
Kodiak and Port Lions
(KdEA)
Old Harbor (AVEC)2
Valdez
Other Communities
Peak
Demand
(thousand kw)
Annual
Generation
(million kwh)
Peak
Deman.d
(thousand kw)
Annual
Generation
(million kwh)
Peak
Demand
(thousand kw)
Annual
Generation
(million kwh)
-
-
Interior I
Fairbanks Area
City of Fairbanks (FMU)
Golden Valley (GVEA)
Subtotal,Fairbanks Area
Fort Yukon (FYU)
Tok (AP&T)
Other Communities
Total,Interior Region
21.0 90.0 51.8
.-!2.:..L 211.0 --!l.h..Q-
66.9 301.0 182.8
0.4 0.7 0.7
0.8 2.9 1.2
__1._2_2.I 2.I
69.3 306.7 186.8
221.0 161.I 687.3
610.0 379.0 1,790.0
831.0 540.I 2,477.3
1.8 1.2 2.9
4.3 2.0 7.0
5.4 3.6 B.7
842.5 546.9 2,495.q
IUtility estimates from REA power requirements studies,and consultant's studies,generally through 1982,and
extended to 1990 by APA at same growth rate.
2APA estimate based on 1972 generation and various growth assumptions.
Source:Alaska Power Administration,Alaska Power Survey,1974.
l--.__"'".__..__....
1 t 1 'I 1 1 1 '1 1 1 J
\
1
_J
--_._._-~--'._'--~-'_.
p
Source:Alaska Power Administration,Alaska Power Survey,1974.
APPENDIX TABLE 3
ALASKA POWER ADMINISTRATION
"STATEWIDE AND REGIONAL UTILITY LOAD ESTIMATES,1972-2000"
Actual Requirements Estimated Future Requirements
1972 1980 1990 2000
Peak Annual Peak Annual Peak Annual Peak Annual
Demand Energy Demand Energy Demand Energy Demand Energy
Region (thousand kw)(million kwh)(thousand kw)(million kwh)(thousand kw)(million kwh)(thousand kw)(million kwh
Hil!her Rate of Growth
Southeast 52 229 140 600 310 1,360 640 2,820
Southcentral 224 1,037 680 2,990 1,640 7,190 3,590 15,740
Interior 69 307 200 870 460 2,020 970 4,230
Southwest,Northwest,
Arctic,Combined 10 47 30 140 80 330 160 710
Total 355 1,620 1,050 4,600 2,490 10,900 5,360 23,500
Likelv Mid-Range Rate of Growth
Southeast 120 530 230 1,010 400 1,740
Southcentral 610 2,670 1,220 5,350 2,220 9,710IInterior1807803401,500 600 2,610
Southwest,Northwest,
Arctic,Combined 30 120 60 240 100 440
Total 940 4,100 1,850 8,100 3,320 14,500
Lower Rate of Growth
Southeast 110 470 180 810 260 1,150
Southcentral 530 2,340 980 4,290 1,470 6,430
Interior 160 680 270 1,200 390 1,730ISouthwest,Northwest,
I
Arctic,Combined 30 110 50 200 7f>290
Total 830 3,600 1,480 6,500 2,190 9,600
I 120/0 Growth Assumption!i Statewide Total 4,020 12,450 38,800
II,---~--