HomeMy WebLinkAboutLarsen Bay Feasibility Study Final VolD Aug 1982...
LARSEN BAY ,. CONTENTS
-Section Page
FOREWORD iv ...
I • SUMMARY ..
A. General 1-1
B. Area Description 1-2
.-C. Power Planning 1-2
D. Description of Recommended .. Hydroelectric Project 1-3
E. Base Case Plan 1-4
F. Economic Analysis 1-5
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G. Environmental and Social Impacts 1-6
H. Conclusions and Recommendations 1-6 -
II. INTRODUCTION
A. General 11-1
B. Purpose 11-2
C. Project Area Description 11-2
D. Authority 11-3
E. Scope of Study 11-4
F. Study Participants 11-7
G. Report Format 11-8
H. Acknowledgments 11-9
-I I I . STUDY METHODOLOGY
A. General 111-1
B. Prereconnaissance Phase 111-1
C. Field Study Phase 111-2
D. Office Study Phase 111-2
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IV. BASIC DATA
A. General
B. Hydrology
C. Geology and Geotechnics
D. Surveys and Mapping
E. Land Status
F. Previous Reports
V. ALTERNATIVES CONSIDERED
A. General
B. Alternative Projects
C. Description and Evaluation
VI. RECOMMENDED HYDROELECTRIC PROJECT
VII.
A.
B.
C.
D.
E.
F.
General
Recommended Project Description
Turbine-Generator Selection
Field Constructibility
Project Energy Production
Project Operation Scheme and Controls
PROJECT ENERGY PLANNING
A. General
B.
C.
D.
E.
Projection Considerations
Energy Demand Projections
Base Case Plan
Recommended Project Plan
VIII. PROJECT COSTS
A.
B.
C.
D.
General
Cost Estimating Basis
Base Case Plan
Recommended Project Costs
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IX. ECONOMIC ANALYSIS
A.
B.
C.
D.
E.
F.
General
Project Analysis Parameters
Base Case Economic Analysis
Recommended Hydroelectric Project
Economic Analysis
Economic Comparison of Projects
Unit Costs and Project Timing
X. ENVIRONMENTAL AND SOCIAL EFFECTS
XI.
A.
B.
C.
General
Environmental Effects
Socioeconomic Effects
PROJECT IMPLEMENTATION
A.
B.
C.
General
Project Licenses, Permits and
Institutional Considerations
Project Development Schedule
XII. CONCLUSIONS AND RECOMMENDATIONS
A •
B.
Conclusions
Recommendations
BIBLIOGRAPHY
APPENDIX
A. Project Drawings
B. Hydrology
C. Geology and Geotechnics
D. Detailed Cost Estimate
E. Environmental Report
F. Letters and Minutes
G. Space Heating Installation and Cost
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This vol ume,
recommendations of
FOREWORD
Volume D, presents
a study intended to
the findings
fully assess
and
the
economic, technical, environmental, and social viability of a
hydropower project for the village of Larsen Bay. Volumes B, C
and E present feasibility studies for hydropower projects for
the villages of King Cove and Old Harbor and a reconnaissance
study for Togiak, respectively. Volume A is a summary report
incorporating the findings, conclusions, and recommendations of
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A. GENERAL
SECTION I
SUMMARY
Several prior studies of alternative means of supplying
Larsen Bay with electrical energy had recommended a hydro-
electric project as the best available source. As a direct
resul t of these prior studies and recommendations, the Alaska
Power Authori ty has authorized a feasibili ty study to
investigate in detail the hydropower potential in the vicinity
of Larsen Bay.
This report summarizes the act i vi ties conducted for the
feasibili ty study. These activi ties included projections of
energy needs, formulation of a hydroelectric project and an
alternative base case to meet the electrical energy needs of
Larsen Bay, detailed analyses of economic feasibility, and
preparation of an environmental assessment of the effects of
the project.
The results of the study indicate that a 270 kilowatt (kW)
hydroelectric project can be constructed at Larsen Bay, that
the project is considerably more economical than the base case
alternative, and that the environmental effects of the project
are minor.
The total cost of the proposed Larsen Bay hydroelectric
project is $2,821,400 in January 1982 dollars. The project
could be implemented and on-line by January 1, 1985, if a
decision to proceed with the project is made by December
1982. During an average water year, the proposed project would
be capable of supplying more than 85 percent of the electrical
needs and about 14 percen t of the space heat ing needs in the
project area. The equi valent savings in diesel fuel in the
year 2001 would be about 69,000 gallons for direct electrical
demand and 16,000 gallons for space heating.
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B. AREA DESCRIPTION
The village of Larsen Bay is located near the junction of
two fjords, Larsen Bay and Uyak Bay, on the northwest coast of
Kodiak Island. Shelikof Strait, separating Kodiak Island from
the mainland, lies 14 miles to the northwest and the ci ty of
Kodiak lies 60 miles to the east. The selected hydroelectric
power site is on Humpy Creek, a small tributary of Larsen Bay
fjord about one mile south of town. The general project area
and the proposed project site are shown on Plate I of
Appendix A.
C. POWER PLANNING
Power planning for the Larsen Bay project was conducted
using standards set forth by the Alaska Power Authority.
Previously recommended potential hydroelectric sites were
investigated and the project area was surveyed to evaluate
potential new sites. After detailed study, a project was
selected and then compared with a base case plan.
Present energy demands for Larsen Bay for direct electrical
uses and space heating were estimated and future uses in these
categories were projected. The projections were based on fore-
casts of increases in the number of customers and increased
usage rates. Population growth and employment, legislation and
other political influences, life style changes, and other
factors can influence future energy demands but they were not
explicitly treated.
The period of economic evaluation used was 53 years, which
starts in January 1982 and extends for the 50-year life of the
hydroelectric project after the estimated on-line date of
January 1985. The energy demands for Larsen Bay were increased
for 20 years starting in January 1982 and extending through
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December 2001. The demands were then held level over the
remainder of the economic evaluation period.
For the proposed hydroelectric project, it was assumed that
the first priority of use for the energy produced would be the
direct electrical needs of Larsen Bay, and any remaining energy
would be used for space heating.
D. DESCRIPTION OF RECOMMENDED HYDROELECTRIC PROJECT
Hydroelectric power plants transform the energy of falling
water (head) into electrical energy. Generally, a hydroelec-
tric power project consists of a dam to produce the head or to
divert stream flows so that they can be passed through a
turbine-generator system to produce electric power. In the
case of the recommended Larsen Bay Hydroelectric Project, a low
weir will act as a dam to divert water from Humpy Creek through
an inlet structure and into a penstock (conveyance pipe). The
~enstock will be 27 inches in diameter and will carry the water
about 2700 feet to the powerhouse, where it will be passed
through the turbine-generator system to produce electric
energy.
The powerhouse will have the capacity to produce 270 kW of
electrical power. A transmission line will be constructed to
transmit the power generated at the plant to Larsen Bay.
Access to the powerhouse facilities will be provided by
building a short length of new road to link up with an existing
road that extends to an existing and abandoned dam near the
site of the new powerhouse. The transmission line will follow
the alignment of the new access road and the existing road to
Larsen Bay. The general plan and features of the proposed
project are presented on Plates I through VI I of Appendix A.
Photographs of the project area are presented in Exhibits VI-1
through VI-4 at the end of Section VI and in the Environmental
Report, Appendix E.
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Under the recommended plan, energy generated by the hydro-
electric plant will have to be supplemented by diesel genera-
tion. Larsen Bay does not currently have a central diesel
generating plant and the plan will therefore require the
construction of diesel facilities for standby and backup
power. The hydroelectric generation will be adequate to meet
the direct electrical needs of Larsen Bay during most of the
year; however, from December through March diesel will be
needed to supplement the hydroelectric generation. A new
electrical distribution system will also be required since none
currently exists.
During an average wa ter year the proposed hydroelectric
project will be capable of supplying more than 90 percent of
the electrical needs of Larsen Bay and approximately 20 percent
of the space heating over the life of the project.
Average annual energy production from the hydroelectric
plant will be 1.09 million kilowatt-hours (kWh) and the average
annual plant factor will be about 46 percent, which means that
the plant is expected to generate about 46 percent of the
energy that it could produce if the turbine-generator unit was
operated continuously at full capacity.
E. BASE CASE PLAN
The base case plan formulated to meet the projected energy
demands of Larsen Bay assumed that the use of individual
existing diesel generating plants would be discontinued and a
new centralized diesel generating plant would be constructed.
Because of apparent economic benefits, it was assumed that the
proposed system would also incorporate waste heat recovery that
would be used for space heating. The possibility of installing
wind generation equipment was also considered, and was found to
be economically viable.
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It was assumed that the diesel system for the 1982 base
case would require about 51,500 gallons of fuel oil per year;
this amount was expected to increase over the next 20 years to
more than 80,000 gallons per year. Waste heat recovery was
expected to displace the use of 17,000 gallons of fuel oil per
year by the year 2001. The wind generators are expected to
displace about 12,000 gallons of oil by 2001.
F. ECONOMIC ANALYSIS
The economic analysis was based on the Alaska Power
Authority criteria that compare the net present worth of the
proposed base case costs to the net present worth of the pro-
posed hydroelectric project costs using specified real price
escalation and discount rates. Net present worth is the
present value of the costs that would be incurred over a
comparable economic evaluation period of 53 years for both
projects.
The present worth of the base case only, that is, diesel
generation, is $7,532,100. If this cost is reduced by the
savings that could be realized from the installation of waste
heat recovery, the present worth is $6,725,100; further
reducing this cost by· the benefit obtainable from wind
generation yields a present worth of $6,432,000. All costs
except the cost of the hydroelectric project and its diesel
supplement were considered as adjustments to the base case.
The cost of the space heating credit was added to the base case
because it represents a benefit that would not be realized if
the base case plan was implemented. The next present worth of
the base case after all adjustments is $7,348,600.
For the proposed hydroelectric project, the present worth
of the costs, is $5,941,700. A comparison of this net present
cost with the base case net present costs indicates that the
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recommended hydroelectric project is considerably more
economical than the alternative base case.
An additional measure of project feasibility is the bene-
f i t/ cost ( B/C) ratio. The B/C ratio is the present worth of
the project benefi ts divided by the· net present worth of the
project costs. For this project, the B/C ratio for the base
case only is 1.268. The B/C ratio after adjustment for waste
heat recovery is 1.132; after additional adjustment for wind
generation, the B/C ratio is 1.067; and after all adjustments,
the B / C rat i 0 is 1. 23 7 • Th e s e B / C rat i 0 sin d i cat e t hat the
proposed hydroelectric project is highly feasible.
G. ENVIRONMENTAL AND SOCIAL EFFECTS
The environmental study results indicate that the effects
of the project will be minor due to the limited scope of the
project activities, the inability of salmon to spawn above the
old diversion dam on Humpy Creek, the abundance of alternative
areas available for trapping, hunting, and general recreation,
and the availability of measures to mitigate potential effects
from the construction and operation of the facilities. Minor
socioeconomic benefits will occur as a result of project
construction and maintenance and cbeaper electric rates made
possible by the project. Additional environmental studies do.
not appear to be warranted unless regulatory agencies or local
residents express additional concerns.
H. CONCLUSIONS AND RECOMMENDATIONS
The studies conducted for this report ind ica te that the
proposed 270 kW hydroelectric project is feasible and that the
energy demands of Larsen Bay are suff icient to ut il ize the
hydroelectric plant's planned capaci ty. The proposed project
is a more economic means of meeting the area's future electric
needs than the base case diesel alternative. Environmental
effects of the proposed project are minor.
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In view of these findings, it is recommended that actions
be initiated to implement the project.
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SECTION II
INTRODUCTION
A. GENERAL
The village of Larsen Bay is located near the junction of
two fjords, Larsen Bay and Uyak Bay, on the northwest coast of
Kodiak Island 60 miles west of the city of Kodiak. Larsen Bay
does not now have a central generation or electrical distribu-
tion system. About one-half of the residents get electrical
power from small, privately owned generators and the remainder
do wi thout. It has been assumed that wi thout a hydroelectric
project the local community will develop a central generation
and distribution system based on ci ty-owned diesel generators
in the same way that other similar villages have done. How-
ever, diesel systems for electrical generation have several
serious drawbacks, especially in remote locations --availabil-
ity and cost of diesel fuel, expected shortages and increased
expense of fuel in the future, potential maintenance problems,
and the cost and availability of parts or even whole systems.
The installation of hydroelectric generating capacity would
potentially alleviate the major problems inherent in the diesel
systems and provide dependable generating capacity over a long
time span.
This section describes the purpose and scope of the study,
the physical and economic characteristics of the project area,
and the organizational makeup of the participants in the study.
B. PURPOSE
The primary purposes of this feasibili ty study were to
prepare a recommendation on the best configuration for develop-
NBI-388-9523-II 11-1
ing a dependable source of hydroelectric energy supply for
Larsen Bay and to determine the engineering, environmental, and
economic feasibility of the project.
The recommended hydroelectric project was compared wi th a
base case plan that consisted of diesel generating units sup-
plemented by wind generation and a central distribution system
that would be augmented with additional units as necessary to
accommodate growth. Earlier studies had determined that these
alternatives were the most promising sources of electrical
energy for Larsen Bay.
C. PROJECT AREA DESCRIPTION
Larsen Bay is located on the west side of Kodiak Island.
The village site lies along a beach with a gradual incline.
The background is covered wi th low alder, brush and grass.
Away from the water side, the village is surrounded by moun-
tains that rise to more than 2000 feet and treeless terrain.
The local sea coast is marked by deep, narrow scoured straits
and fjords and by steep, rocky sea bluffs.
Larsen Bay is only accessible by air and by water. No
roads connect the town wi th any other town on Kodiak Island.
Uyak Air Service, based in Larsen Bay, serves area villages on
an on-call basis. Kodiak Western Airlines makes one flight
daily, Monday through Friday. Other companies are also avail-
able to provide chartered flights.
The economy of Larsen Bay has traditionally been based on
fishing and cannery work. A large salmon cannery was operated
in the town until recently when it ceased operations. However,
the fishing industry will remain the primary commercial acti-
vi ty and the fishermen will use other means to market their
catch. The Larsen Bay Tribal council has appl ied for funds
from U.S. Housing and Urban Development (HUD) to develop a fish
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smoking operation using some of the facilities of the old
cannery.
Electrical power is provided by individual generators at
the residences. Approximately 20 five kW generators provide
electricity to 25 or 30 households. Generally, electricity is
used only during the evening hours. The school has two 60 kW
generators.
Humpy Creek to the south of the vi llage is the proposed
location for hydropower development. The creek originates in a
hanging valley above Larsen Bay fjord. It passes through the
village of Larsen Bay and discharges into Larsen Bay. The pro-
posed diversion site is about one mile south of Larsen Bay.
The general plan and drawings of Appendix A show the location
and features of the proposed project.
The climate of Kodiak Island is dominated by a strong
marine influence. The area is characterized by moderately
heavy precipitation and cool temperatures. High clouds and fog
occur frequently but the area has Ii ttle or no freezing wea-
ther. The humidity is generally high and temperature variation
is small. The mean maximum temperature varies from 320 F to
620 F. Average rainfall is 23 inches per year. Winds of 50 to
75 knots are frequent, with 120 mph winds estimated for a 100-
year storm. Icing is primarily a problem for ships.
D. AUTHORITY
The Alaska Power Authority (APA) has authorized studies to
prepare the "Detailed Feasibili ty Analyses of Hydroelectric
Projects at King Cove, Larsen Bay, Old Harbor and Togiak."
This particular report, Volume D, summarizes the studies con-
ducted for Larsen Bay. APA is a public corporation of the
Department of Commerce and Economic Development, State of
Alaska.
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E. SCOPE OF STUDY -
In general the scope of the study consists of an aaalysis -of the the costs and benefits of a hydroelectric project, a _
comparison of these costs and benefits with those for the base
case plan for the village, and an environmental assessment of
the effects of the project. To accomplish these goals, the
following activities were necessary.
1 . Data Accumulation
Data collected included existing flow records, topographi-
cal mapping, present and future demands for power, applicable
laws and regulations, existing reports, and other applicable
information that was available.
2. Site Reconnaissance
The purposes of the site reconnaissance were to supplement
and verify the data gathered, to collect topographical, hydro-
logical, environmental, and geotechnical data, and to determine
the accessibility of the site. The conceptual design of pro-
ject features was established in the field.
3. Site Surveys
A topographic survey was conducted at the site of the
diversion, penstock, powerhouse, and transmission line in
sufficient detail for use in final design.
4. Hydrology ,
Hydrologic data were developed from the limited available
data. A suitable method was established to prepare a
streamflow table, a flow duration curve, and the seasonal
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distribution of the flow duration curve.
flooding problems were also considered.
Diversion and
5. Geotechnical Investigations
Geotechnical investigations were conducted to determine
material sources, slope stabili ties, and load-bearing charac-
teristics of the foundations for all structures in the project.
6. Base Case Plan
A base case plan was analyzed that assumed the establish-
ment of a diesel generation and distribution system, supple-
mented by wind generation, and least-cost additions for future
generators. Included in this analysis was an assessment of
current energy usage and a forecast for the life of the pro-
ject. The cost of establishing and continuing the use of the
diesel generators assumed for the base case plan provided a
basis for determining the value of power at the site. Data
regarding the energy potential and cost of wind generation at
Larsen Bay were provided by another contractor to APA.
7. Power Studies
Several different types of turbines and
installed capacities were evaluated to determine
configuration.
8. Environmental Overview
a range of
the optimal
The environmental investigation was conducted to identify
any environmental constraints that might prohibit project
development.
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9. Design
A layout of tbe project was designed and sizes and capaci-
ties of water-carrying, structural, and control components were
determined. All features of tbe project were designed in
sufficient detail for use in preparing a cost estimate.
10. Cost Estimates
Cost estimates, including direct and indirect costs, were
prepared using a present cost base escalated to the anticipated
time of construction.
11. Economic Analysis
The project was analyzed using tbe economic criteria of tbe
Alaska Power Autbori ty. The general metbodology employed was
to compute the present net worth of tbe costs of tbe proposed
bydroelectric project over a 50-year project life and to
compare this value to the present net worth of the costs of the
base case plan over tbe same 50-year project life.
12. Environmental Assessment
A detailed environmental analysis was conducted based upon
tbe final design and layout of the project.
13. Conclusions and Recommendations
Tbe report presents findings on tbe feasibility of tbe
project and recommends a future course of action to be
followed.
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14. Public Meetings
Public meetings were conducted in Larsen Bay at the begin-
ning of the project studies to obtain comments from local citi-
zens. Another public meeting was held in Larsen Bay to present
the findings and conclusions of the study and to solicit public
comments. All letters and comments received from federal and
state agencies were answered by APA with changes incorporated
in the text of the final report as required. A copy of the
comments and replies is contained in Appendix F.
15. Report
A draft report was submitted to the APA in February 1982,
and the final report incorporating all comments was submitted
in August, 1982.
F. STUDY PARTICIPANTS
DOWL Engineers, of Anchorage, Alaska, was the primary
contractor for the study. DOWL was assisted by two subcon-
tractors--Tudor Engineering Company of San Francisco, Cali-
fornia, and Dryden & LaRue of Anchorage, Alaska. The primary
role played by each of the participants is covered below.
1. DOWL Engineers
DOWL Engineers, an Alaskan partnership, performed the
project management function and provided the primary contact
wi th the Al aska Power Author i ty. DOWL collected basic data,
participated in the hydrology studies, and had the prime
responsibility for the local coordination activities, geology
and geotechnics, and the environmental, ground survey, stream
gaging, and wind velocity aspects of the investigation.
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2. Tudor Engineering Company
Tudor, as principal subcontractor, supplied all hydro-
electric expertise for the project.· They directed data collec-
tion and conceptual design of facilities; assisted with public
meetings; assisted and provided direction in evaluating the
base case plan and power values, formulating cost estimates,
and making the financial and economic evaluation; and furnished
advice on the aspects of the envi ronmental problems that are
unique to hydroelectric projects. Tudor prepared the initial
draft of the project report.
3. Dryden &. LaRue (D&L)
The partners in D&L are electrical engineers registered in
Alaska. Much of the electrical work was accomplished in close
cooperation with this firm. Transmission lines and backup
diesel generation facilities were involved as well as questions
related to reliability and integrated operation of the proposed
system with existing village systems. D&L and Tudor estab-
lished the value of power and the present and projected power
demands. D&L provided the feasibili ty designs and cost esti-
mates for the transmission lines and appurtenant electric
features.
G. REPORT FORMAT
Pages, tables, figures, and exhibi ts in this report are
numbered within the sections in which they appear. Within sec-
tions, the tables, figures, and exhibits are placed at the end
of the text. References noted in the text are listed in the
Bibliography.
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H. ACKNOWLEDGMENTS
The cooperation of the many federal, state, and local agen-
cies and local residents contacted during the course of the
study is gratefully acknowledged. This list includes, but is
not limited to, the Alaska Power Administration, the Alaska
Department of Fish and Game, the Alaska Department of Trans-
portation, the Alaska Department of Natural Resources, the U.S.
Army Corps of Engineers, the U. S. Geological Survey, and the
U.S. Fish and Wildlife Service. The assistance of the Rockford
Corporation and the Locher Construction Company, a subsidiary
of Anglo Energy Company, is also acknowledged. Individuals who
were especially helpful include Don Baxter of APA, Roger Smith
of ADF&G, and Dora Aga and Frank Peterson of Larsen Bay.
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SECTION III
STUDY METHODOLOGY
A. GENERAL
This section describes the general methodologies employed
and steps taken to complete the project studies and analyses.
In general, the study proceeded in three phases--
pre-reconnaissance, field studies, and office studies. Each
project phase is described briefly below and the resul ts are
covered in detail in the following sections of the report and
the appendices.
B. PRE-RECONNAISSANCE PHASE
This phase consisted of initial data collection and
analyses, obtaining access permits, coordination with resource
agencies, and evaluation of the existing material and reports.
A brief one-day visi t was made to Larsen Bay by the project
team to conduct the initial field investigation. Later a
member of the project team returned to hold the initial public
meeting and inform the residents of project investigation
activities. During the initial field evaluation, available
alternative hydroelectric sites were inspected and preliminary
environmental evaluations of all sites were made. Office
studies of alternative sites and environmental conditions had
preceded the initial field work. The project team on this
initial visit consisted of individuals with geologic, geotech-
nical, hydroelectric, hydrological, environmental, and
electrical expertise. All individuals participated in evaluat-
ing the alternatives and conducting the field investigations •
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C. FIELD STUDY PHASE
The field studies were conducted several weeks after
initial pre-reconnaissance activities, mobilization, and field
planning were completed. Detailed site investigations spanning
several days were made by the hydroelectric engineers to define
the location of the project features. They were aided in this
work by the geology and geotechnic team, which also made a
detailed investigation of geology and soil conditions following
final selection of the feature locations. Field environmental
and hydrologic investigations were also conducted in parallel
as the field conceptual design work was completed.
The field survey team immediately followed the hydro-
electric and geotechnical teams to the field to conduct
detailed surveys. A stream gage was also established by the
hydrology group.
Data were gathered from Larsen Bay regarding the present
and planned generating conditions of the city system.
D. OFFICE STUDY PHASE
The final and most extensive phase of the study was the
office study phase where all data gathered from the field and
all accumulated data and information were analyzed and addi-
tional investigations were conducted to complete the project
activities.
Separate reports were produced for the hydrology, geology
and geotechnical, and environmental activities. They are
included with this report as Appendices B, C and E, respec-
tively. The environmental appendix also includes information
on permitting requirements, social impacts, and land status.
NBI-426-9523-III 111-2
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Project energy planning studies were conducted to define
tbe year-by-year electrical and beating demands of Larsen Bay.
To meet tbe
were analyzed to
requirements, various
determine tbe opt imal
installed capacities
project size and tbe
conceptual design of tbe bydroelectric project. Tbese tasks
were completed with tbe aid of tbe maps prepared from tbe field
activities. Detailed cost estimates were tben prepared based
on tbe final size of 270 kW and tbe completed project layouts.
Tbe economic analysis was tben conducted to complete tbe
project analysis activities, and a draft report was prepared.
Following a preliminary review of tbe report by tbe Alaska
Power Autbority, an additional meeting was beld in Larsen Bay
to solici t public comments. Tbe draft was circulated to all
concerned state and federal agencies. After receipt and con-
sideration of comments, tbe final report was compiled. Appen-
dix F contains a copy of all tbe comments received and tbe
replies prepared by APA and tbe contractor.
NB1-426-9523-111 111-3
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SECTION IV
BASIC DATA
A. GENERAL
This section describes in general the basic data used in
the preparation of the Larsen Bay report. Included are
hydrologic, geologic and geotechnical data, surveys and
mapping, land ownership status and previous reports.
B. HYDROLOGY
The primary thrust of the hydrologic studies for the Larsen
Bay hydroelectric project concerned the development of a flow
duration curve, an annual hydrograph, and a flood frequency
curve for Humpy Creek. A complete report of the steps taken to
achieve those items is covered in the hydrology report included
with this report as Appendix B.
One year of streamflow data was available for Humpy Creek
(USGS Gage No. 15296480). The general methodology employed to
develop the Humpy Creek flow duration and hydrograph was to
first develop an estimated value for the Humpy Creek mean
annual flow. Dimensionless flow duration curves and hydro-
graphs were then developed from the records of a long-term
stream gaging station, Myrtle Creek on Kodiak Island. Applying
the Humpy Creek mean annual flow to the dimensionless curves
then yielded a specific flow duration and hydrograph for Humpy
Creek.
1. Mean Annual Flow
The long-term mean annual flow was developed using three
different estimating techniques--conversion of the 1981
measured flow, the modified rational formula, and regional
NBI-388-9523-IV IV-1
analysis. The three methods yielded similar values and the
Humpy Creek mean annual flow was taken as 13.0 cfs.
2. Flow Duration Curve
The closest gaged stream with an adequate length of record
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is Myrtle Creek on Kodiak Island (No. 15297200), 70 miles to •
the east of Larsen Bay. A comparison of dimensionless curves
from three basins on Kodiak Island showed considerable
similari ty. On this basis the Myrtle Creek curve developed
from 17 years of daily record was adopted as the type of curve
for small, mountainous maritime basins in southwest and south-
central Alaska. The Humpy Creek flow duration curve presented
as Figure IV-1 is based on Myrtle Creek scaled to the ratio of
its respective mean annual flows.
3. Annual Hydr9graph
Based on the same data and reasoning that went into
determining the mean annual flow and the flow duration curve,
an annual hydrograph was developed based on monthly flows at
Humpy Creek. The resul ting annual hydrograph is presented in
Figure IV-2.
4. Flood Frequency Curve
Estimates of flood discharges are based entirely on
regional analyses. Regression equations obtained through
regional analyses were first applied to the gaged stream to
test their applicability. The basin and climatological
characteristics of Humpy Creek were then entered to obtain the
following flood frequency values.
NBI-388-9523-IV IV-2
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Q10 = 250 cfs
Q25 = 325 cfs
Q50 = 400 cfs
Q100= 485 cfs
These data are plotted on a frequency curve and presented
as Figure IV-3.
C. GEOLOGY AND GEOTECHNICS
The purpose of the geologic and geotechnical studies con-
ducted for this report was to assess the geologic hazards,
establish appropriate design criteria, explore material borrow
sites, and provide background information for environmental
studies. A complete Geology and Geotechnics Report covering
these items in detail is included as Appendix C. A summary of
the report is included below.
1. Site Topography
Larsen Bay is a communi ty located on Larsen Bay on Kod iak
Island, Alaska. Kodiak Island is essentially an isolated
extension of the Kenai Peninsula in the Gulf of Alaska. Larsen
Bay is an arm of the larger Uyak Bay, which is a major north-
south trending bay opening to Shelikof Strai t between Kodiak
Island and the Alaska Peninsula.
Larsen Bay is now a fjord; however, during glacial times it
was filled with ice and was a tributary to the major ice mass
occupying Uyak Bay. Because mul tiple glacial advances have
brought ice to this entire area, the hills are generally smooth
and rounded, hanging valleys are common, and valleys tend to
have a parabolic cross section . Elevations in the immediate
area range to approximately 3000 feet. Stagnant ice topography
and abandoned outwash channels are common.
NBI-388-9523-IV IV-3
The proposed dam site is on Humpy Creek, which drains the
hills to the south of Larsen Bay and flows through town into
the bay. The stream is relatively straight and is incised into
bedrock in the project area.
2. Regional Geology
The Kodiak Formation that constitutes the bedrock underly-
ing the Larsen Bay si te has been interpreted as a deep-sea
trench deposit of Late Cretaceous age that has been accreted to
the continent. These rocks are for the most part marine
turbidi ties and range from well-Ii thified sil tstones to fine
sandstones.
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Glaciation on Kodiak Island has probably extended from -
Miocene time to the present. The glacial deposi ts at Larsen
Bay date from Late Pleistocene time. Both till and glacial
outwash are present.
3. Site Geology
The geology of this area consists of glacial till, outwash,
and alluvial fan deposits that mantle bedrock belonging to the
Late Cretaceous Kodiak formation. The bedrock is a slate with
poor to moderate fissility.
The proposed diversion site is in a very narrow gorge
within the bedrock. The walls of the gorge are nearly vertical
in many areas along the stream and at the diversion si te.
Other than removing minor amounts of loose rock at the surface,
no special problems are anticipated for the abutments. The
rock is not highly weathered or fractured and appears competent
for this use.
There are two options for the si te of the road and pen-
stock, one on each side of Humpy Creek. Each option could
NBI-388-9523-IV IV-4
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follow the existing road up to the present dam across Humpy
Creek. This road ends near the west abutment of that dam.
Option A, considered the better option, could also follow the
west side of Humpy Creek to the existing dam.
Most of the Option A route is inexpensi ve. Upon reaching
the stream, Option A would need about 125 feet of blasted road
and one stream crossing to reach the staging area or three
stream crossings and no blasting to reach the staging area.
There are few geologic hazards and little likelihood of future
major maintenance problems.
4. Construction Materials
Gravelly sand is present in both the outwash deposi t and
the alluvial fan deposit. The fan deposits are probably
superior for construction because there is an existing gravel
pit that can be used. If higher quality materials are
required, beach materials are a possibility.
5. Seismic Hazards
The Larsen Bay proposed dam site is in a seismically active
area. Strong ground motion is the principal seismic hazard.
Recommended design criteria should be based upon a 50-year life
of the structure and a base acceleration of 40 to 50 percent of
the acceleration due to gravi ty. Surface faul ting or major
ground failure is not expected at the dam site.
D. SURVEY AND MAPPING
A detailed ground survey, based on the project configura-
tion marked in the field by the hydropower engineering, was
made of the Humpy Creek Site between November 6 and 10, 1981.
The survey and the drawings produced from them included ground
control; traverse, profile (1 inch = 50 feet horizontal, 10
NBI-388-9523-IV IV-5
feet vertical) and valley cross sections of two al ternative
penstock routes on the east and west sides of the canyon; and
topographic mapping (1 inch = 20 feet, 2-foot contour interval)
and cross sections of the diversion dam and alternative
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powerhouse sites in the vicinity of the abandoned cannery -
diversion dam. Elevation datum was assumed. --Prior high altitude stereo aerial photography of the area _
was available. This was used to produce a general topography
map (1 inch = 700 feet, 20-foot contour interval, assumed
control) of the lower portion of the Humpy Creek Basin. The
locations of the airstrip and other recent developments within
Larsen Bay were obtained from the Larsen Bay Community Map.
The project is located on the USGS Kodiak C-6, 15 minute
Quadrangle Map (1:63,360; 100-foot contour interval, 1952).
E. LAND STATUS
A map showing land status in Larsen Bay and the project
area is presented in Figure IV-4. The diversion weir to be
constructed across Humpy Creek, the borrow site location near
the diversion weir and a portion of the proposed trail from the
diversion weir to the powerhouse are within lands for which the
surface estate has been interim conveyed to Koniag,
Incorporated, as part of their entitlements under the Alaska
Native Claims Settlement Act of 1971 (ANCSA), Public Law 92-
203. Interim conveyance is used in this case to convey
unsurveyed lands. Patent will follow interim conveyance once
the lands are identified by survey.
The powerhouse, and an al terna ti ve borrow si te near the
city solid waste disposal area are located on lands which are
interim conveyed or patented for surface and subsurface estates
to the ci ty of Larsen Bay. The proposed transmission route
al ternatives from the powerhouse to Larsen Bay traverse both
NBI-388-9523-IV IV-6
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patented private, city of Larsen Bay, Townsite Trustee, and
patented Koniag Corporation property. An airport lease, Serial
Number AA 9087, is near the powerhouse and the final transmis-
sion route alternative should take this into account.
Larsen Bay has a federal townsi te, U. S. S. 4872, wi th the
patent issued to the Bureau of Land Management Townsite Trus-
tee. The Trustee has deeded occupied parcels to the residents
and some vacant lots to the ci ty. Other subdi vlded property
remains with the Trustee. A permit would be required for the
transmission line to cross Trustee lands and it can be issued
by the U.S. Department of Interior after an affirmative reso-
lution by the City Council.
All of the interim conveyed lands identified above are also
part of the Kodiak National Wildlife Refuge as classified and
withdrawn by Public Land Orders 1634, 5183, and 5184. All
lands that were part of a national wildlife refuge before the
passage of ANCSA and have since been selected and conveyed to a
Native corporation will remain subject to the laws and
regulations governing use and development of such refuges as
outlined in Section 22(g) of P.L. 92-203.
F. PREVIOUS REPORTS
Studies of power potential projects for the Larsen bay area
are described below:
1. "Hydroelectric Power Potential for Larsen Bay and Old
Harbor, Kodiak Island, Alaska Appraisal Evaluation, May
1978, " by Uni ted States Department of Energy, Alaska Power
Administration.
This report presents rough appraisals of potential
hydroelectric projects to serve the villages of Larsen Bay and
Old Harbor on Kodiak Island.
NBI-388-9523-IV IV-7
The potential hydroelectric generation plan consists of
utilizing water from the stream that flows north through the
village. The plan assumes a 1000 kW generating plant operating
under 300 feet of net head, with a design hydraulic capacity of
50 cfs. The average power potential is 2,704,000 kWh. The
total investment cost of the project was estimated to be
$2,300,000 or $2,300 per kW. The average cost of power would
be 13 cents per kWh.
The study concluded that the project at Larsen Bay has
potential as a run-of-stream plant. The plant cannot meet
power demands during the winter or during dry periods in the
summer. It would have to be operated in conjunction wi th a
diesel plant, and the value of the hydro would be based on the
fuel oil saved. The approximate value of diesel generated
power using $1.00 per gallon oil at 11 kWh per gallon is 9.1
cents per kWh. With a demand of 2 million kWh/year, the cost
of hydro power would be 13 cents/kWh. With a larger demand, it
would be 7 cents per kWh.
It was concluded that the Larsen Bay project appears to
have a chance of feasibility.
2. "Report of Geologic Investigation--Old Harbor, Larsen
Bay and Port Lions--Kodiak Island, Alaska," 1978, by Robert M.
Retherford.
At the request of the Alaska Power Administration, this
geologic study was made of the hydropower site proposed in the
Alaska Power Administration report listed as report number 1
above. The report covered general geology of the Larsen Bay
area and site geology for the powerhouse, penstock route, and
dam si te. It also made recommenda tions for future geologic
explorations.
NBI-388-9523-IV IV-8
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3. "Preliminary Feasibili ty Designs and Cost Estimates
for Hydroelectric Project Near Larsen Bay, Alaska," prepared
for the U.S. Department of Energy, Alaska Power Administration,
Juneau, Alaska, by Robert W. Retherford Associates of
Anchorage, Alaska, January 1980.
This report presents a preliminary feasibility study of the
site proposed in the Alaska Power Authority (APA) report of
1978 . On are con n a iss a n c e bas is, the rep 0 r t co n sid e r s all 0 f
the components involved in a feasibility study. It was
concluded that the project would cost $3,232,200 for an
installed capacity of 1120 kW. The total annual cost would be
$293,440. The average cost of hydro power in 1981 was
estimated to be 9.41 cents/kWh based upon the sale of 3,115,800
kWh. The 1981 benefit/cost ratio would be 1.08.
4. Regional Inventory and Reconnaissance Study for Small
Hydropower Projects--Aleutian Islands, Alaska Peninsula, Kodiak
Island, Alaska, by Department of the Army, Alaska District,
Corps of Engineers. Prepared under contract by Ebasco Services
Incorporated, July 1980 draft--October 1980 final.
The purpose of this study was to provide a reconnaissance-
grade report outlining the potential for hydropower development
at each of 36 isolated communities stretched over 1500 miles in
the Aleutian Islands, the Alaska Peninsula, and Kodiak Island.
At Larsen Bay, three potential power si tes were analyzed.
Site 1 was located about three miles southwest of Larsen Bay.
Si te 2 was located about three-quarters of a mile south of
Larsen Bay, and Site 3 was located about two miles west-
northwest of Larsen Bay. All three streams were unnamed in
this report. Si te 2 corresponds to the si te analyzed in the
1978 APA report.
NBI-388-9523-IV IV-9
The report lists the existing energy source, demographic
characteristics, economic characteristics, land ownership, and
environmental concerns.
Conclusions reached were shown in the following table:
Site Power Factor
No. Percent
1 67
2 67
3 67
1 43
2 43
3 43
5. "Reconnaissance
Al terna ti ves for Akhiok,
Ouzinkie and Sand Poin t , "
by CH2M HILL, May 1981.
Annual Cost Benefit/Cost
per kWh Ratio
$ .032 5.25
.033 5.09
.054 3.11
.050 3.36
.051 3.29
.084 2.00
Study of Energy Requirements and
King Cove, Larsen Bay, Old Harbor,
prepared for Alaska Power Authori ty
The purpose of the study was to identify and assess the
present and future power needs of each community and to assess
the power project alternatives available to that community. It
served as a basis for recommending more detailed data
collection activities, resource assessmen ts, or detailed
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alternatives.
The report concluded that the Humpy Creek Hydroelectric
Project plan is the lowest-cost power alternative to Larsen Bay
and the centralized diesel generation plan is the second-
lowest-cost al terna ti ve. The base case plan of decentralized
diesel generation is the highest-cost plan. Waste heat
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recovery would be an attractive addition to the school _
generator. _
NBI-388-9523-IV IV-10
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6. "Summary-Reconnaissance Study of Energy Requirements
and Al terna ti ves for Larsen Bay," prepared for Alaska Power
Authority by CH2M HILL, July 1978.
This study presents the resul ts of the study listed as
No. 5 evaluating energy requirements and alternative
electrici ty sources for the communi ty of Larsen Bay on Kodiak
Island.
The preferred al ternative electrici ty supply system would
consist of a standby central diesel generator, serving the
entire village and a hydropower plant on Humpy Creek. This
would require the installation of a central electrical
distribution system for the village. The recommended standby
plant would consist of one 120 kW diesel engine generator.
The recommended project would have a rated capacity of 300
kW and would require an initial investment of $3.3 million. A
more detailed feasibility investigation is recommended for the
Humpy Creek project •
NBI-388-9523-IV IV-11
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70
60
50
40
\
30 \
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20
,~ MEAN ~,NNUAL FLOW 13 cfs
_ 10
UJ ...
o· -~ o
i 0 o 20
" " "--..........
40 60
PERCENT (0/0 ) OF TIME FLOW EXCEEDED
HUMPY CREEK
FLOW DURATION CURVE
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80
~
100
FIGURE
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SECTION V
ALTERNATIVES CONSIDERED
A. GENERAL
The request for proposals for the Larsen Bay Hydroelectric
Project indicated that past studies had identified Humpy Creek
as the most attractive site for development. Locating a physi-
cally and economically viable hydroelectric power project in
the vicinity of Larsen Bay presents certain difficulties.
Adequate head is readily available in several streams near the
town, but the drainage areas are small and thus provide only
limited water supplies. The superiority of Humpy Creek on this
count has long been recognized. This section summarizes the
alternatives considered during this phase of the work and
presents the reasoning that led to the conclusion that Humpy
Creek did indeed provide the best available site.
B. ALTERNATIVE PROJECTS
Four sites were proposed in previous studies and all of
these sites were considered. Two sites were subject to
detailed ground reconnaissance before selecting a site on lower
Humpy Creek. Power output estimates are based on the average
annual flow developed in this study, which corresponds to the
30 percent flow duration or avai labi I i ty, and on gross head
minus penstock losses. Transmission lines are assumed to
terminate at the Town Hall because no electrical distribution
lines now exist in Larsen Bay. The values ci ted therefore
differ from those previously reported.
NBI-388-9523-V V-l
B. DESCRIPTION AND EVALUATION
Before field activities were undertaken, a preliminary
evaluation of the sites was made on the basis of prior reports
and map and stereo air photo interpretation. Final evaluation
and the selection of the lower Humpy Creek site were made by
the field team while they were in Larsen Bay. The locations of
the sites studied are shown in Figure V-1. Selection of a site
was based on information similar to the data presented in Table
V-1. Head, flow, and penstock length were measured in the
field at both Sites 1 and 2 before Site 1 was selected.
Primary consideration was given to the ability of the alterna-
ti ve projects to meet Larsen Bay I s projected power needs as
weighed against the relative constructibility and cost of the
requi red st ructures. ReI iabi I i ty of the water supply, length
of penstocks, geotechnical problems, access roads and transmis-
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iii
sion lines, and environmental effects were major considera-•
tions. The following discussions highlight that evaluation. •
Site 1 was described in the request for proposals for this
feasibili ty study and was recommended in the July 1981 CH2M
HILL reconnaissance study (1981) and the Ebasco study (1980).
The superiority of Humpy Creek at either Site 1 or 2 is
evident. The powerhouse would be located near an existing road
at the edge of the village and the water supply is the largest
available within a wide radius. Site 1 was selected over Site
2 on the basis of a better match of power production to esti-
mated future demand and a considerably shorter penstock. It
shares with Site 2 the potential problem of being immediately
below the badly deteriorated cannery diversion dam; however,
direct delivery of water from the plant tailrace to the cannery
pipeline may prove to be an asset should the cannery reopen.
The primary disadvantage of the site is the difficult construc-
tion access to the diversion weir and upper penstock.
NBI-388-9523-V V-2
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Si te 2 would locate its powerhouse on the opposite bank
from Site 1. A 16-inch-diameter penstock would be laid along
the west side of the valley to a long diversion dam in the
upper basin, 1500 feet beyond the USGS stream gage. Construc-
tion conditions through an open series of terraces would be
generally excellent. The high-head configuration of the Humpy
Creek development is inherently attractive because it shifts
the power equation toward the stable head component and away
from the widely fluctuating flow component. However, the site
was finally rejected on the basis of its excessively long
penstock. A 1500-foot shorter configuration was considered but
it would require suspending about 500 feet of penstock from the
unstable cl i ff face above the falls. This approach was not
considered prudent.
Site 3 is located on the north shore of Larsen Bay north-
west of the 01 d cannery. I ts power is inadequate and its
transmission line extending under the bay would entail exces-
sive costs.
Site 4 is located 2.5 miles west of the village on the
south shore of the bay. While the site is superior to Site 3,
it is not competitive with Humpy Creek.
NBI-388-9523-V V-3
i
No. Steam
1 Humpy Creek, Lower
2 Humpy Creek, Upper
3 Unnamed Creek No. 1
4 Unnamed Creek No. 2
NBI-388-9523-V-1
TABLE V-1
ALTERNATIVE PROJECTS
LARSEN BA Y
Dr ainage Average Gross Penstock
Area Flow Head Length
(sq mi) (cfs) (ft) (ft)
6.28 13 200 2700
3.22 6.7 740 7000
(North) 1.5 3.1 370 2900
(West) 1.9 3.9 600 4800
i
Transmission Power
Line Remarks
(mi) (kW)
0.7 270 Selected
0.7 320
2.5 75
2.9 150
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SECTION VI
RECOMMENDED HYDROELECTRIC PROJECT
A. GENERAL
Hydroelectric power plants transform the energy of falling
water (head) into electrical energy. In general, a hydro-
electric power project consists of a dam to produce the head or
to divert stream flows; an intake and penstock or flume to con-
vey the water to the hydraulic turbine; the turbine itself,
which is coupled to a generator to produce electrical energy;
accessory electrical equipment; and a transmission system to
transmit the energy to a distribution system or user.
This section describes these features as they are
specifically adapted for the Larsen Bay Hydroelectric Project
and the methodologies used in selecting the type of turbine and
generator, the size and number of units and the configuration
of the penstock and power plant. Field constructibility,
project energy production, and project operations are also
discussed.
B. RECOMMENDED PROJECT DESCRIPTION
In general, the features of the recommended project consist
of diversion facilities that include a low weir and an inlet
structure that will be located on Humpy Creek about one mile
south of Larsen Bay at the confluence with the first tributary
that joins the creek from the southeast. The diverion weir
will divert water into a 27-inch-diameter penstock that will
transport it 2700 feet along the right bank of Humpy Creek to a
powerhouse wi th an install ed capac i ty of 270 kW. From the
powerhouse, a transmission I ine will extend to the town of
Larsen Bay along the alignment of the existing road. This road
NBI-411-9523-VI VI-l
will provide access to the project facilities. A concrete mat
will be constructed where the short access road needed to link
up the powerhouse with the existing road crosses Humpy Creek.
A staging area will be provided in the flood plain near to the
proposed diversion facilities. Access from the staging area to
the diversion dam will be by a trail along the pipeline. These
features
and are
through
are presented on Plates II through VI in Appendix A
described more specifically below. Exhibits VI-l
VI-4 show photographs of the project area and the
proposed locations of project features.
The diversion weir will consist of a prefabricated steel
module that wi 11 be bolted to a concrete apron. The at t i tude
of the upstream face of the gate will be about 45 degrees from
vert ical and the gate will be fitted with back supports. The
steel weir module will be connected by a pin at the base and
the upper sect ion wi 11 be supported by steel st ruts. A neo-
prene flap wi 11 provi de the necessary water tigh tness at the
connection of the weir diaphram to the apron. A prefabricated
steel inlet structure will be located at the right of the weir.
The 27-inch-diameter penstock will be about 2700 feet in
length and will consist of both steel and fiberglass sections
constructed along the right bank from the diversion weir to the
powerhouse. The penstock will consist of buried fiberglass
pipe whenever possible to eliminate the need for anchor
blocks. Steel pipe will be used where rock foundation material
is encountered or where other reasons dictate above-ground
installa tion. Typical pens tock access road sect ions are shown
on Plate III of Appendix A.
The power plant at the terminus of the penstock will have
an installed capacity of 270 kW and it will utilize an impulse-
type turbine and a synchronous-type generator.
NBI-411-9523-VI VI-2
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The operating head will be 180 feet, wi th a design dis-
charge of 23.8 cubic feet per second (cfs). The 270 kW rating
is based on assuming a nominal turbine efficiency of 83
percent. It is possible that a turbine manufacturer may
guarantee a higher turbine efficiency; if so, this will
increase the turbine-generator rating proportionally. With
reasonable turbine efficiency the turbine-generator will
perform satisfactorily on turbine discharges as low as 10
percent of rating. Turbine discharges as high as 48 cfs will
not cause a problem or create excessive maintenance costs for
the turbine-generator unit. (A detailed "explanation of the
turbine-generator selection
following subsection.)
process is incl uded in the
The turbine-generator and all other equipment except the
power transformer will be placed indoors at the powerhouse
site. The turbine, speed increaser, flywheel, and generator
will be shipped preinstalled on fabricated skids and no field
assembly or alignment of those components will be necessary.
The powerhouse construction will utilize a reinforced-
concrete floor slab and a prefabricated metal building about 32
feet by 34 feet to house the equipment. Permanent lifting
fac il i ties will not be prov ided; however, an oversi zed equip-
ment door will permit portable lifting facilities to be used if
they are required for a major overhaul. Since equipment of the
type being used is very rugged, the normal annual overhaul
functions should not require the lifting of heavy equipment
sections.
The three-phase power transformer will be mounted on a pad
and placed outdoors adjacent to the powerhouse structure. A
chain link fence with a barbed guard at the top will encompass
the transformer and form the switchyard enclosure. The
generator breaker will be inside the powerhouse.
NBI-411-9523-VI VI-3
A transmission line from the powerhouse switchyard to the
town of Larsen Bay will utilize a transmission voltage of 12.47 ---
kV. The configuration of the line will be single pole with
single cross arms. Poles will be located at 350-foot intervals
with the lines running along the centers of the cross arms. A
sketch showing the detailed configuration is included in
Appendix A as Plate VI.
As previousl y noted, no d ist r ibut ion system and cen tral
genera tion fac il i ties curren tl y exist in Larsen Bay. They
would have to be constructed to implement a hydroelectric proj-
ect but they are not considered here as a project feature since
they would also be necessary for a base case relying primarily
on diesel generation. The diesel generation base case was used
as an alternative for comparison with the proposed hydro-
electric project. This point is discussed more extensively in
Section VII, Project Energy Planning.
C. TURBINE-GENERATOR SELECTION
In the selection process, the type of turbine and type
of generator were first selected from the available al terna-
ti ves and the install ed capac i ty was t hen determined by an
incremental cost/benefit economic analysis. This selection
process is described below.
1. Description of Available Turbines
Conventional turbine equipment that is commercially availa-
ble is classified either as impulse or reaction turbine equip-
ment.
An impulse turbine is one having one or more free jets
discharging into an aerated space and impinging on the buckets
of the runner. The jet size increases as the head on the
turbine decreases. For low-head applications the cost of the
NBI-411-9523-VI VI-4
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impulse turbines is generally not competitive with the reaction
type. The impulse turbine can, however, be operated economi-
cally on heads as low as 150 feet.
For the 180-foot operating head of this development, there
are two suitable types of impulse turbines, Pelton and Turgo.
In the Pelton type the jet impinges the runner near its extrem-
i ty and in the plane of the runner. In the Turgo type the jet
impinges the runner from the side about mid-runner. For the
same hydraulic conditions, the Turgo type will operate at about
twice the speed of the Pel ton type. There is very Ii ttle
difference between the two types in either efficiency or
methods of control.
A Francis turbine is one having a runner wi th a large
n umber of fixed bl ades attached to a crown (top) and a band
(bottom) • The d imensional configuration of the runner is
designed to suit the head conditions of the application.
Designs are commercially available to suit head conditions
ranging from 15 to 1500 feet. In general the Francis turbine
is not competi tive wi th the propeller type below a head of
about 60 feet.
A propeller turbine is one having a runner resembl ing a
propeller with a small number of blades, usually four, five or
six, to which water is suppl ied in an axial direction. The
blades are attached to the hub of the runner. The blade angle
is adjusted to sui t the head cond i tions of the appl ication.
Runners are available in either fixed-blade or adjustable-blade
designs. The suitable head range of propeller turbines is from
15 to 110 feet. The 180-foot head of the Larsen Bay Project is
beyond the head range of the propell er turb ine. Accord ingl y,
this type of turbine was not included in the study.
In addition to the impulse and reaction turbine, a proprie-
tary design called the Ossberger turbine is available for head
NBI-411-9523-VI VI-5
ranges from 15 to 500 feet. The runner design is classified as
a cross flow that derives energy from both impulse and reaction
turbine principles. Water is forced through a rectangular
cross section and guide vane system and then through the hori-
zontal runner blades. This flow pattern has the unique
advantage of working out refuse such as grass and leaves and
melting snow and ice that may be forced between the blades of
the runner as the water enters. Any quantity of water from 16
percent to 100 percent of the design flow is usable wi th
optimum efficiency.
2. Description of Available Generators
Generators can be of the synchronous or induction type.
Induction generators are often considered more practical for
the smaller turbine-generator installations because they cost
less and require less maintenance. They require no excitation
and need only a squirrel-cage rotor that uses no wire windings
or brushes. Furthermore, they do not run at exact synchronous
speed and complex equipment is not needed to bring them on
line. They cannot be used to establish frequency, however, and
must be connected to a system with synchronous generators
because they take their exci ta tion from system current. The
generators produce electric energy with a high degree of
efficiency.
Synchronous generators are usually three-phase star or
Y-connected machines with one end of each winding connected
together in common and the other ends used as line terminals.
The al terna ting-current synchronous genera tor, or al terna tor,
delivers its induced alternating current directly to the exter-
nal circui t. It is used where transmission is to be sent over
long lines. The alternating current can be transformed to the
desired transmission voltage.
NBI-411-9523-VI VI-6
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For this development the synchronous-type generator is used
because it is necessary to establish frequency.
3. Selection of Turbine Type
As previously discussed, the 180 feet of head available for
the Larsen Bay Hydroelectric Project is suitable for operating
either a reaction turbine (Francis) or impulse turbine (Pelton
or Turgo). For the size of this unit, the costs of equipment
delivered at the job si te are about equal. Installation costs
are generally lower for the impulse types since few imbedded
parts are necessary.
_ Any change in the rate of penstock flow will set up a pres-
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sure wave that increases the penstock pressure when the flow
rate is decreased and lowers the penstock pressure when the
flow rate is increased. Destructive pressure risks, known as
water hammer, are possible if the flow is suddenly stopped.
This water problem can be limited by building a surge chamber
near the power plant, by installing a bypass valve (known as a
pressure-relief valve) at the power plant, or by a combination
of both methods.
A surge chamber, to be effective, would have to be so high
tba tit would no t be pr act ical. A bypass valve would have to
be capable of discharging the same amount of water as the tur-
bine and in addi tion would have to be able to dissipate the
same hydraulic power as the turbine. A valve of this type can
be constructed for a modest cost, 10 percent of the turbine
cost.
On a Francis turbine, the penstock flow is controlled by
the opening and closing of the turbine wicket gates. An
electrical load rejection will cause the wicket gates to close
as fast as is permi tted by the turbine governor. Too slow a
closing allows the turbine-generator speed to rise to destruc-
NBI-411-9523-VI VI-7
tive velocities. Too fast a closing resul ts in high penstock
water hammer pressures. The use of a turbine bypass valve and
proper governor setting can hold the rise in both the speed and
water hammer pressure within reasonable limits. A sudden
decrease in electrical load initiates signals from the turbine
governor that cause the bypass valve to open enough to maintain
a near-constant penstock flow. The bypass valve then slowly
closes under controlled conditions and the rise in water hammer
pressure is negligible.
Impulse turbines are equipped with a jet deflector. The
jet deflector intercepts and deflects a portion of the jet or,
in the case of a load rejection, the entire jet away from the
runner. Under this condition, the rate of flow in the penstock
is constant until the needle valve closes, under control of the
governor, at a rate slow enough to keep the water hammer pres-
sure from materially increasing the penstock pressure.
The guide vanes of an Ossberger turbine serve the same
f unc tion as t he wicket gates in the Fr anc is t urb ine. Both
turb ines have h ydraul icall y simil ar relationships to t he pen-
stock. The previous discussion for the Francis turbine is
applicable to the Ossberger turbine.
Using a Francis (reaction) turbine
would require the use of a bypass valve.
on this development
The bypass valve and
its controls increase the overall power plant costs more than
installing an impulse turbine. On this basis, the impulse
turbine was selected.
4. Selection of Number of Units
Every turbine is most efficient wi thin a range of flows,
with decreasing efficiency occurring beyond this range.
Consequently, more power can usually be generated if two or
more small turbines are selected rather than one large unit.
NBI-411-9523-VI VI-8
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For example, two turbines, each rated at 50 percent of design
flow, will produce more energy over the flow range than one
turbine rated at 100 percent of design flow. However, the two
turbines will generally cost 30 percent to 70 percent more than
the single turbine. The extra value of the energy produced by
the two units must therefore make up for the extra cost of
using two units.
In the specific case of Larsen Bay, the impulse unit to be
used is very efficient over the anticipated range of flows; the
relatively small extra energy that would result from the use of
two units would not justify the extra expense.
was therefore indicated.
5. Selection of Size of Unit
A single unit
The selection of turbine-generator size is primarily a
matter of economics. The larger the turbine size, the larger
the flow that can be accommodated and the more energy that can
be generated; however, the cost is higher. Comparisons were
therefore made of the incremental costs and benefits associated
wi th increments in size. As long as the incremental benefits
exceeded the incremental costs, it was economically justified
to install the larger capacity.
Five turbine sizes in all were investigated for the Larsen
Bay Project. The sizing was based on turbine-generator
capacities based on flows corresponding to the 35 percent to 15
percen t range of exceedance val ues on the Humpy Creek flow
duration curve, Figure IV-1. A value of 180 feet of hydraulic
head (gross head minus losses) was used in all cases.
The average annual energy production for each size was
calculated using the Humpy Creek flow duration curve. For a
given hyd raul ic head, t he area und er such a curve wi thin the
generation limits of the particular size and type of turbine
NBI-411-9523-VI VI-9
under analysis represents the available energy. The result of
the analysis is presented in Table VI-1.
As shown, the range of flows investigated is from 11.9 cfs
(at 35 percent exceedance) to 23.8 cfs (at 15 percent exceed-
ance) with installed capacities of 145 kW to 270 kW and corre-
sponding average annual energy values of 0.82 million kWh to
1.09 million kWh.
The incremental benefits for the sizes analyzed were com-
puted using the differences between the 50-year present worth
of the energy for each addi tional increment and the data and
assumptions presented in Section VII, Project Energy Planning,
and Section IX, Economic Analysis. The incremental costs were
based on the differential costs of the installed unit.
The results of the analysis are presented in Table VI-2.
The incremental benefits far exceeded the incremental costs for
all size increases up to and including the largest size
reviewed, 270 kW at the 15 percent exceedance poin t, which
indicates that this is the optimal size studied. Judgment was
the deciding factor not to size the unit for flows in excess of
the 15 percent exceedance value. Increasing the turbine dis-
charge somewhat beyond this point would probably be economical
but it would decrease the energy available on the low-flow
portion of the flow duration curve and would not materially
increase the annual energy generation. The recommended 270 kW
selection would make available all the energy represented by
the flow duration curve between the 15 and 87 percent time
exceeded. This is graphically illustrated in Figure VI-2,
included at the end of this section.
NBI-411-9523-VI VI-10
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D. FIELD CONSTRUCTIBILITY
For the recommended project, various prefabrication opera-
tions and field procedures would be utilized that would mini-
mize field construction time and also minimize the use of
highly specialized construction skills.
The diversion weir module and the inlet structure would be
shop-fabricated welded-steel structures with shop-applied
protective coatings. After fabrication in Anchorage or
Seattle, they would be shipped wholly assembled to the field.
The field installation of these structures would consist of
simply bolting the weir and inlet structure into place on the
concrete apron.
The 27-inch-diameter penstock would consist of either steel
or fiberglass, depending on the geologic and topographic condi-
tions encountered. The penstock would be steel where rock was
encountered and where the penstock would be elevated. All
other sections would utilize fiberglass pipe.
The steel portions would be placed above ground with steel
collars
steel.
resting on
The steel
either concrete pads or prefabricated
collars would be shop-welded to the pipe
during the fabricating process. The pipe sections would be
connected wi tb flexible bolted couplings and no field welded
connections would be required.
The fiberglass sections of the penstock would be buried to
eliminate the need for anchor blocks at vertical and horizontal
bends. Bell and spigot joints wi th rubber gaskets woul d be
utilized to permi t rapid field installation and the use of
relatively unskilled labor.
NBI-411-9523-VI VI-ll
The powerhouse would consist of a prefabricated metal
building erected on a concrete base slab. A standardized unit
approximately 32 feet by 34 feet would be utilized. Field
assembly of the building would be rapid and unskilled labor
could be utilized. The turbine-generator, the speed increaser,
and the flywheel will be shipped skid mounted, fully assembled
and interconnected to the field. The entire assembly will be
bolted in place on the powerhouse slab, the penstock will be
connected, the electrical wiring will be finished, and the
installation will be completed.
In summary, the maximum use of prefabricated and preas-
sembled components is envisioned. The use of concrete in
general and formed concrete in particular has been minimized
and all major features can be constructed expeditiously using
relatively unskilled labor.
E. PROJECT ENERGY PRODUCTION
As mentioned in subsection C-5 above and as shown in Table
VI-2, the average annual energy production for the recommended
270 kW installation at Larsen Bay is 1. 09 mill ion kWh. Th is
value was derived using the flow duration curve rather than the
average monthly hydrograph since the data used in deriving the
flow duration curve were daily values rather than monthly
averages as shown on the hydrograph.
values have been used to compute
However, the hydrograph
the available peak power
generation that could be expected per month.
graph values exceeded the maximum turbine
Where the hydro-
design flow, the
turbine flow was used for the calculation. The "available peak
power" values were then used on a monthly percentage basis to
distribute the average annual energy value of 1.09 million kWh
to monthly energy values. The results of these compi la t ions
are presented on Table VI-3. The monthly power and energy
production values are shown on Figure VI-1. These monthly
hydroelectic energy values will be used in Section VII, Project
NBI-411-9523-VI VI-12
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Energy Planning, to meet the projected present and future
energy demands of Larsen Bay.
The plant factor, the rat io of energy that coul d be pro-
duced by the turbine-generator if continuously operated at its
rating to the annual energy actually produced, is 46 percent
for Larsen Bay.
F. PROJECT OPERATION SCHEME AND CONTROLS
1. Turbine-Generator
Controls for the turbine-generator unit will load the unit
in response to the connected system demand. A turbine governor
will control the turbine needle valve setting that controls the
turbine discharge and thus matches the turbine-generator elec-
trical output with the connected system load. A small decrease
in the system load will cause the governor to actuate the jet
deflector and a quantity of water will be deflected from the
runner to maintain a constant runner speed. If the lower load
continues, the turbine governor will cause the needle valve to
move to a position where the turbine discharge is of the
correct value and the jet deflector will move out of the jet
stream to allow the full jet to impinge on the runner. As long
as the connected load does not exceed the capacity of the
turbine-generator, the electrical frequency can be held within
approximately plus or minus one-tenth of a cycle.
The turbine-generator is being operated on an isolated
system; that is it is not elect rically connected into a gr id
wi th other operating generating uni ts. Any overload in the
unit will gradually decrease the unit's speed and result in a
corresponding lowering of both line voltage and frequency.
Minor overloadi ng, probably up to about ten percen t, can be
tolerated. But an excessive overload can, if continued, cause
protective devices to trip the unit •
NBI-411-9523-VI VI-13
It is feasible to have a hydraulic turbine-generator unit
operate in parallel with diesel generating units that would be
constructed as a backup and supplemental electrical system.
The hydraulic turbine can be operated as a base load unit and
regulate the system frequency. By proper setting of the diesel
uni t governors, the diesel units can be brought on line and
operated during unusual system demands. The cost of this inte-
grated system was included in the economic analysis.
The turbine-generator will be manually started. A manual
start implies that operating personnel are present during
start up. The operating personnel shoul d physically check the
unit. This check will include opening the turbine shut-off
valve (if closed) and seeing that water is against the needle
valve and all supporting systems are operable. Operating
personnel will then actuate a single control swi tch and the
turbine-generator will automatically start up. When the unit
reaches synchronous speed, it automatically goes on line. The
provision of enough sophisticated equipment and controls to
allow the unit to be started up from a remote location is not
proposed.
Protective devices on the equipment will be capable of
shutting the generating unit down automatically, which would
require a manual startup. The automatic protective devices on
the equipment will sense the internal temperature of the gen-
erator, most bearing temperatures, and critical oil levels.
High temperatures and low oil levels can trip the turbine-
genera tor of f the 1 ine. An alarm wi 11 be given before any
control device shuts down the generating unit.
A pressure sensor will be installed at the penstock intake
to function in concert with the turbine governor to protect the
turbine during periods when there is not
meet the turbine discharge requirements.
sequences will be followed to protect the
NBI-411-9523-VI VI-14
sufficient water to
One of two control
equipment:
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1. The lowering water level at the intake will bring the
governor control into a mode where it will match the
available wa ter quantity wi th the turbine discharge.
If this reduced turbine discharge will not permit the
turbine-generator to produce sufficient power to meet
the load demand, then the turbine-generator wi 11 be
operating in an overloaded condition as discussed
above.
2. If the water level falls to a level where the penstock
will not be running full, then the control will take
the turbine-generator off the line. Based on the flow
dura t ion curve for Humpy Creek, it is expected that
about 13 percent of the time water levels will be too
low for the turbine to run efficiently.
In both cases an alarm will be given prior to shutdown.
maintenance will be performed on a weekly Routine
schedule. The power generated by the turbine-generator need
not be reduced during this maintenance period. The maintenance
will include routine checks to verify that (1) all equipment is
operating in a normal condi tion, (2) none of the equipment is
being operated at a temperature above normal limi ts, (3) all
lubrication requirements are being met, and (4) no discontin-
uity exists in electrical wiring, relays, or controls.
Overhaul maintenance will be performed on an annual basis
and it will be scheduled during the minimum average river flow,
usually in March. The turbine-generator will have to be
removed from the line and electrical power required by the City
System will be provided by diesel generating units. This
annual maintenance period will not normally exceed a week.
This type of maintenance will include the following items:
NBI-411-9523-VI VI-15
1. Areas of wear on the turbine-generator unit will be
reviewed and corrective measures will be initiated in
cases where wear beyond the allowable limi ts set by
the manufacturer has occurred.
2. Electrical insulation checks will be made.
3. Relubrication will be required under the manu-
facturer's recommendations.
4.
2.
Verification will be made that all relays and controls
are properly set.
Diversion Facilities
The design of the steel diversion weir provides a hinge at
the base of the weir at the connection with the concrete apron.
This design allows for periodic lowering of the weir to remove
accumulated sediment. The frequency of such a maintenance
procedure woul d depend on the rate of sediment deposition and
the interference of the deposi ts wi th the diverted flows. If
cleaning is necessary at all, the frequency is not expected to
be more than once a year.
NBI-411-9523-VI VI-16
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Percent Times
Exceedance
.... (Percent)
15
20
25
30 .,..
35
NBI-388-9523-VI-1
TABLE VI-1
TURBINE-GENERATOR SIZING
LARSEN BAY
Turbine Unit Penstock
Discharge Head Size 1.0.
(cfs) (feet) (kW) (Inches)
23.8 180 270 27
18.9 177 210 24
16.2 183 190 24
14.0 188 165 24
11.9 191 145 24
Annual
Energy
Generated
(million
kWh)
1.09
0.99
0.94
0.88
0.82
Plant
Rating
(kW)
145
165
190
210
270
TABLE VI-2
PLANT SIZE AND INCREMENTAL COST AND BENEFIT
LARSEN BAY
Incremental Jan. 1, 1982
Material Net Benefit Incremental
Cost with Heating Benefit
-----------dollars in thousands----------
4,661
2.1 148
4,809
19.0 106
4,915
24.4 128
5,043
52.3 170
5,213
Incremental
BiC Ratio
70.5
5.6
5.2
3.3
NBI-388-9523-VI-2
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Average
Month Flow
(cfs)
Jan 7.9
Feb 6.7
Mar 4.8
Apr 9.8
May 27.1
June 23.7
July 9.4
Aug 10.6
Sept 18.2
Oct 16.8
Nov 12.6
Dec 7.5
TABLE VI-3
AVERAGE MONTHLY PEAK POWER
OUTPUT AND ENERGY GENERATION -270 kW UNIT
LARSEN BAY
Flow
Utilized
for Available
Energy Head Design Peak Monthly
Generation Loss Head Power Energy
(thousand
(cfs) (feet) (feet) (kW) kWh)
7.9 2.04 196 98 56.8
6.7 1.47 197 83 48.2
4.8 0.75 198 60 34.4
9.8 3.14 195 120 70.3
23.8 18.5 180 270 170.8
23.7 18.4 180 269 170.2
9.4 2.89 196 116 67.5
10.6 3.67 195 130 76.2
18.2 10.83 188 216 130.7
16.8 9.23 189 200 120.6
12.6 5.19 193 153 90.5
7.5 1.84 197 93 53.8
Total 1090
NBI-388-9523-VI-3
Percent
of
Total
Annual
Energy
5.2
4.4
3.2
6.4
15.7
15.6
6.2
7.0
12.0
11.1
8.3
4.9
100.0
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SECTION VII
PROJECT ENERGY PLANNING
A. GENERAL
This section presents the projected energy usage for Larsen
Bay over the study period and two alternative means of meeting
this projected demand: the base case plan and the recommended
hydroelectric project. The potential future demand for power
and energy at Larsen Bay was estimated during this study in
order to establish the electrical requirements that the alter-
natives could meet. This information was used to size both
alternatives and was also used for the overall economic
analysis of the project, which is presented in Section IX. ,
B. PROJECTION CONSIDERATIONS
The future demand for power and energy at Larsen Bay is a
function of a number of variables that are difficult to fore-
cast and quantify. These factors include the appliance satura-
tion rate; the effects of cultural factors and traditional life
styles on energy consumption; the rate of modernization of the
Native life style; the amount of employment in the fish
processing industry; the natural variability of the fishery;
the amount of new housing buil t in the area; and numerous
political factors such as the 1981 legislation relating to
energy projects and programs of the APA. Electrical energy at
Larsen Bay is currently supplied by individually owned diesel
generators. Because of this, no base data on power use within
a power grid are available. Electrical use patterns will
almost certainly be altered by the establishment of a central
power system, and the historical data currently available for
Larsen Bay are not necessarily relevant. This situation makes
the quantification of future electrical demand more difficult
NBISF-426-9523-VII VII-1
and uncertain than it would be in the case of an existing power
supply system. The installation of the much cheaper hydroelec-
tric alternative will almost certainly al ter the pattern of
energy and power demand; therefore the forecast presented here
is probably conservative.
1. Appliance Saturation Rate
The number and type of appliances owned by each household,
as well as the extent to which these appliances are used, may
have a significant effect on the amount of power used in the
village. A definite relationship between appliances within a
household and electrical use characteristics is very elusive.
The actual use of energy is more dependent on the number of
people wi thin a given res idence, and their age, habits, and
financial condition. For example, one could predict the annual
electrical use of a refrigerator or freezer because this is
almost independent of activity and habits. Energy use for
electric lights, small appliances, and television is very
susceptible to habits. Energy used for water heaters, washers,
dryers, and dishwashers varies primarily subject to the number
and age of the users. For example, hot water use among
families with small children or babies is very high. One method
of measuring potential future growth and use of appliances is
through a concept known as the appliance saturation rate. The
estimated present percentages of homes having various types of
appliances in Anchorage, the Kenai-Cook Inlet area, and Larsen
Bay are presented in Table VII-l. This information for Larsen
Bay is very approximate and was obtained through several inter-
views with village residents.
The number of appliances in any given household in Larsen
Bay depends on the desire and ability to obtain the appliances,
the cost of electricity, and the available room for the appli-
ances. Larsen Bay does not currently have any form of central
genera t ion or elect rical d istri but ion system. Approximately
NBISF-426-9523-VII VII-2
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one-half of the homes in the village receive electrical power
from small, pri va tely owned generators; the remainder of the
homes do not have any form of electrical supply. When cheap
electricity becomes available, all of the homes in the village
will probably begin to acquire appliances.
The purpose of presenting the Anchorage and Kenai-Cook
Inlet data in Table VII-1 is to provide a compar ison with
largely urbanized areas that have much greater unit consumption
of electrical energy. Appliance saturation rates (and sizes of
appliances) for rural Alaskan villages such as Larsen Bay can
be expected to increase in the future.
The base year 1980 energy use rate per residential ~ustomer
was about 4400 kWh, as discussed subsequently. This indicates
a fairly high per customer use of electrici ty in this area.
The homes in Larsen Bay are small and those homes that do have
electricity have all of the appliances that they are likely to
acquire. At present no change in the quali ty of housing at
Larsen Bay is anticipated. Any significant increase in per
customer consumption of electricity at Larsen Bay would proba-
bly be the result of a change in the type of housing common in
the village. The Kodiak Island Housing Authori ty is currently
preparing an application for HUD funding to construct 13 single
family housing uni ts. The available data are insufficient to
make predictions of this nature. Therefore, the rate of
consumption of energy was assumed to increase slowly. For
purposes of this study, it was assumed that the use rate would
increase to about 5,270 kWh annually by 2001. The Ebasco
( 1980) regional inventory assumed that households would
increase energy consumption to 6,000 kWh per year by the year
1995, exclusive of electric space heating. The CH2M HILL
report pred icted that the increase in energy use would be 12
percent annually from 1981 through 1985, and four percent
annually thereafter. The new policies permitting opportunities
for reductions in price, discussed in the next section,
NBISF-426-9523-VII VII-3
---indicate that this projected 5,270 kWh annual residential rate •
is on the conservative side.
2. The Influence of Price on the Demand for Power
The 1981 legislation relating to the projects and programs
of the APA may result in some reduction in the cost of power at
Larsen Bay. This possible decrease in power cost could be
expected to be accompanied by an increase in per customer use.
Data from the Alaska Power Administration have been
developed to show the 1980 individual customer use of electric-
i ty versus cost for all towns, ci ties, and villages for which
information was available in Alaska. This information is
summarized in tabular form in Table VII-2 and graphically in
Figure VII-l. While the data on Figure VII-1 are somewhat
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scattered, the trend is evident that low power costs result in •
higher usage and high power costs result in lower usage. In
economic terminology, this relationship of price to quantity
consumed is referred to as "elasticity" of demand.
As indicated by Table VII-2, unit energy costs of less than
100 mills per kilowatt-hour are generally accompanied by high
use rates, in excess of 7000 ki Iowa t t-bours per customer per
year. As the unit price of power increases, the per customer
use tends to decrease, with the 48 AVEC Villages having energy
costs in excess of 400 mills per kilowatt-hour and annual per
customer demands of about 2000 kilowatt-hours. The two
different utilities listed for Fairbanks provide an even
clearer example of the elasticity of the demand for electrical
energy; in this case where the cost of energy was 75.1
mills/kWh the annual demand was 10,519 kWh per customer and
where the cost of energy was 122.2 mi lIs/kWh the demand was
5501 kWh per customer.
NBISF-426-9523-VII VII-4
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The general conclusion is that in the higher ranges of
price there is significant elasticity in demand. Lower energy
costs result in higher energy usage and this can also be
expected to occur in Larsen Bay with the advent of lower
prices. The actual amount of higher usage, however, is very
difficul t to quantify. For purposes of this study no attempt
has been made to predict the higher usage other than to
incorpora te a moderate increase in the
energy in the projections covered below.
probably on the low side.
C. ENERGY DEMAND PROJECTIONS
per customer use of
These projections are
For the economic evaluation, a period of 50 years after the
proposed date for the hydroelectric project to come on-line was
considered. As requested by APA, the period of study was
started in January 1982. The demand for power was assumed to
increase for 20 years from the beginning of the period of study
and was then held at a constant value for the remainder of the
study. The planning period is the 20-year period during which
increased demand for energy was recognized, from January 1982
to December 2001. The economic evaluation period extends past
the planning period to 2034, 50 years after the on-line date
for the hydroelectric alternative.
The overall energy demand for Larsen Bay for purposes of
energy planning has been broken into two primary categories:
direct electrical demand, which includes residential, small
commercial, and school; and space heat ing demand. A cannery
formerly operated at Larsen Bay; however, it has been
dismantled and was not considered for purposes of this study.
Projections for each of these categories and the combined
requirements are presented below.
NBISF-426-9523-VII VII-5
1. Direct Electrical Demand
The general approach followed in estimating direct elec-
trical demand was to break down the direct city system demand
----
into general types of customers normally identified by util-..
ities in projecting electrical users in small villages. These
include the number of residential, small commercial, and school
customers. Residential use represents the largest proportion
of usage, and for Larsen Bay it amounted to about 60 percent.
The base year of 1980 demand was taken from available data on
popula t ion, average number of individuals per customer unit,
and per customer usage estimates. From the CH2M HILL (1981)
report, a village electrical demand of 132,000 kWh per year and
30 residences were used to derive the per customer use rate of
4,400 kWh per customer per year. The R. W. Retherford and
Associates study (1980) indicates an annual per customer use
rate of 4960 kWh.
Projections beyond 1980 were not directly tied to estimated
growth in population. Because of significant changes that
could occur in the number of residential customers as a result
of existing housing that are not currently supplied with power
being electrified, it was found that residential demand was
more closely correlated to the number of housing units than to
population growth. This was substantiated by AVEC records of
similar communities. Growth in demand from 1980 to 1985 may be
heavily influenced by the electrification of the entire
vi llage. The increase in residential use for this period was
assumed to be nine percent; after 1985, the annual growth rate
was assumed to be two percent. The CH2M HILL report predicted
that the increase in energy use would be 12 percent annually
from 1981 to 1985, and four percent annually thereafter.
Peak demands were calculated by applying typical load
factors for each type of consumer group. Load factor data were
derived from AVEC historical data as well as data from other
NBISF-426-9523-VII VII-6
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typical utilities. Historically, the load factor tends to
improve as the load increases. This improvement is explained
by added street lighting, refrigeration, and other loads that
tend to level the power demand. Projected total annual direct
electrical demands over the planning period to 2001 are
shown in Table VII-3. An annualized table showing these
demands is included as Table VII-10.
No data were available on the monthly energy demands for
Larsen Bay. The only source of data found during the course of
the study for monthly demands for small rural villages such as
Larsen Bay was the 1979 AVEC records for Togiak. Using these
data, the monthly percentages of the total annual energy demand
were computed. These values are presented in Table VII-4 and
are used in Tables VII-9A to VII-9D to compute the projected
monthly energy demands from 1980 to 2001. While the total
amount of energy used in a given village will vary consider-
ably, it was assumed that the monthly use pattern would be
fairly similar for rural villages throughout the state; the
Togiak values were therefore assumed to be applicable to Larsen
Bay. At any rate, any error resulting from this assumption is
expected to be small.
2. Space Heating Demand
The fuel oil use rate for Larsen Bay for 1980 was obtained
from the CH2M HILL report (1981) on energy alternatives. This
report also gave estimated values for 1990 and 2000. These
values were used with interpolated and extrapolated values for
1985 and 2001 to compute the annual heating requirements for
Larsen Bay in terms of equivalent kilowatt-hours of electrical
energy. These values are presented in Table VII-5. Note that
the total potential demand is far greater than the expected
output of the hydroelectric project; thus it does not con-
stitute a constraint on the economic analysis.
NBISF-426-9523-VII VII-7
The monthly heating demands over the study period were
computed using the number of heating degree days per month from
the Larsen Bay Communi ty Profile and applying the calculated
monthly percentages to the annual heat demand values from Table
VII-5. The resulting projected monthly heating demands for
1980 to 2001 are presented in Table VII-6.
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The actual daily variation in heat demand is not necessar-..
i ly represented by the monthly demand for heat; however, for
ease of computation, differences between monthly totals and
actual usable amounts of heat were ignored. The estimates of
heat demand presented herein are conservative.
3. Total Energy Demands
The projected annual energy values for direct electrical
and heating demands are presented in Table VII-7. The projected
monthly energy demands for these same categories are presented
in Table VII-8. Also shown in the tables are the total direct
electrical demand and the total combined demand (direct
electrical and heating demand).
The annual energy projections from Table VII-7 are pre-
sented in graphical form in Figure VII-2, where the energy
demands are plotted for each year of the study period. Also
shown is the annual hydroelectric energy production for the
sizes stud ied (145 kW to 270 kW). Figure VII-2 presents two
separate graphs of the same information: overall data and
detailed data. The overall data graph illustrates that a very
large proportion of the combined energy demand is heating
demand. The detai led data graph presents in more detai 1 the
relative values of the various demands and available generation
values.
The distribution of hydroelectric generation used to meet
direct electrical demand, and the use of excess hydroelectric
NBISF-426-9523-VII VII-8
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energy for space heating, is presented as Tables VII-9A through
VII-90. These tables are discussed in detial on pages VII-16
and VII-17.
The monthly energy projections from Tables VII-9A to VII-90
are presented in Figure VII-3, again as an overall data graph
and a detailed data graph. These graphs show the relationship
on a monthly basis between the energy demands and the hydro-
electric energy available over the study period. The graphs
illustrate the general periods where the hydroelectric energy
would have to be supplemented by diesel generation to meet the
village needs and when excess energy would be available for
space heating. As shown, during an average water year the
hydroelectric· plant would generate energy sufficient to meet
more than 90 percent of the village's direct electrical
demand. The annual values of direct electrical demand, and the
generation mix that would be met by the hydro project and the
supplemental diesel, are presented as Table VII-10.
O. BASE CASE PLAN
The base case plan as originally formulated for Larsen Bay
included diesel generation supplemented by waste heat
recovery. This plan was mod ified to include wind generation.
The plan as originally formulated is presented below, and is
followed by the wind generation plan .
1. Original Plan
The base case plan to meet the projected energy demands
presented above was developed assuming that a central diesel
generation plant and distribution system would be built at
Larsen Bay during the summer of 1982. This plant would consist
of three diesel generating units with 100 kW of capacity each,
NBISF-426-9523-VII VII-9
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resulting in a firm capacity of 200 kilowattsll. This capacity a
should be adequate to meet peak demands on the system through-
out the period of study based on previously stated assumptions
about projected demands for power. The diesel engines would be
replaced every 15 years, and the entire structure would be
replaced every 30 years. The lives of the engines were
shortened from 20 to 15 years because the small machines
selected for this site run at a higher speed than the larger
systems, and would therefore wear
diesel engines operate at 1200 rpm.
this site would operate at 1800 rpm.
out faster. Commonly used
The machines selected for
In order to implement the diesel system, it would also be
necessary to install fuel storage facilities. For purposes of
this study, it was assumed that the fuel storage facilities at
Larsen Bay would consist of two 50,000-gallon tanks surrounded
by a protective dike. The city has applied for a grant to
purchase four 10,000 gallon fuel tanks from the cannery.
The base case would also utilize heat recovered from the
diesel generators to the maximum extent feasible. The fuel
that the engines use represents energy injected into the
system, which is about 138,000 BTUs for every gallon of fuel
oil consumed. About one-third of this thermal energy is con-
verted into electrical energy, about one-third is rejected in
the form of heat from jacket water and oil cool ing, and the
remaining one-third is rejected, also in the form of heat, in
the hot exhaust gases.
The heat energy from the jacket and oil cooling water is
the easiest portion of the waste heat to recover. This can be
accomplished by installing a simple heat exchanger and heating
11 In figuring firm capacity, the largest unit is omitted.
NBISF-426-9523-VII VII-l0
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water to be used for space heating. The temperature available
is about 180 to 1900 F, which is quite usable for hydronic
heating or air plenum radiators.
The exhaust heat is of much higher quality, 600 to 10000 F,
but it is much more expensive and complicated to capture. The
exhaust is forced through what looks like a standard fire tube
or water tube boiler, either heating the water to just below
boiling or producing steam. The hot water is much easier to
deal with, so most systems control the flows to prevent the
formation of steam.
The jacket water heat is almost entirely usable, while the
-typical recovery efficiency of the exhaust heat system is
between 30 and 40 percent at full load. For purposes of this
study, it was assumed that only jacket heat would be recovered
and that exhaust heat recovery would not be feasible from a
first cost or maintenance standpoint.
One real problem in waste heat utilization is that the heat
available is directly dependent upon the electrical generation
requirements at any particular time. The requirements for
heating the buildings are, however, dependent upon the weather.
There is no viable method at present to store this heat over
long periods. Therefore, much available heat energy cannot be
utilized simply because there is no need for it at the time it
is avai lable. This is called coincidence between supply and
demand .
For this study it was assumed that about 60 percent of the
available jacket heat could be utilized each year. As the
generation increases over time, the heat is available more of
the time and therefore somewhat greater usage could be
expected. It was assumed that public buildings in the area
would be connected ini tially and that this would not change
substantially over time. Their utilization was assumed to
NBISF-426-9523-VII VII-11
increase by 1.5 percent per year. The amount of usable heat
and growth rate were based on experience with similar projects.
Data on installations of this type are scarce; however, these
projections are felt to be conservative.
The community hall, clinic, old school, and new school at
Larsen Bay would use the heat recovered from the diesel
system. The existence of these heating loads was verified from
the community profile and from interviews with local reidents.
The items associated with waste heat recovery include the
installation of equipment in the powerhouse and the use of
radiators and insulated pipes to convey the water to and from
the point of use. The equipment in the powerhouse would
consist of heat exchangers, piping, a circulating pump, and fan
controls. Insulated pipes would be laid from the powerhouse to
the point of heat demand. Hot water radiation would be
installed in the public buildings. Waste heat could be
recovered and used for heating build ings up to 2000 feet from
the powerhouse. The equipment in the powerhouse would have to
be replaced when the diesels are replaced. The equipment for
waste heat recovery from the water jackets and oil cooling is
essentially 8n extension of the diesel engine cooling system,
has no moving parts, and should last at least 20 years. The
hot water distribution lines and radiators should last for the
entire economic life of the project.
The diesel generation system at Larsen Bay would consume
about 51,530 gallons of fuel oil in 1983, and this amount could
be expected to increase to more than 80,000 gallons annually by
2001. The fuel oil savings from waste heat recovery would be
about 17,000 gallons annually in 2001.
NBISF-426-9523-VII VII-12
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2. Wind Generation Plan
The possibility of supplementing the existing diesel system
with wind generation was investigated as part of the base case
analysis. At the direction of the Alaska Power Authority, all
wind data and wind system costs were obtained from a report
entitled "Bristol Bay Regional Power Plan, Detailed Feasibility
Analysis, Interim Feasibility Assessment Report", 1982, by
Stone and Webster. Unpublished data and information developed
by Stone and Webster in conjunction with this report was also
utilized.
Wind energy is an emerging technology, but has, to date,
proved to be economically feasible only under certain condi-
tions. The investment cost associated with wind generation is
very high, and the cost of other energy sources must be greater
than at least 15 cents per kWh to justify the investment.
Standard equipment uses induction generators, and system
stabili ty becomes a problem if more than about 20 percent of
the total system power is from wind. For some limited applica-
tions, such as remote cabins and communications installations,
direct current generators and banks of storage batteries may be
practical. Some configurations that use excess wind energy for
space heating show good overall economics.
The only proven wind generators that are currently avail-
able have capacities of 10 kW or less. However, units up to
100 kW are currently becoming commercially available and are
expected to be dependable. The application of this equipment
is subject to some limiting restrictions.
In order to be efficient the wind turbine must operate at
low wind speeds and yet be rugged enough to withstand high
gust ing and wind. The gear boxes, towers, and blades must
operate under these adverse conditions almost continuously. At
this time few manufacturers are able to demonstrate the
required reliability under Alaska conditions.
NBISF-426-9523-VII VII-13
The electrical interface to the utili ty system is also
fairly complex wi th some reliabili ty problems. The simplest
and most reliable systems use induction generators, but these
units introduce another limiting factor, stability problems.
The wind varies widely in available energy. This variation
can be over seconds, days or months. Energy must be stored to
bridge the periods of low wind. There are many ideas about
possible storage mediums including compressed
hydrogen generation, pumped hydro storage,
thermal.
air, batteries,
flywheels, and
All of these methods have a reasonable theoretical basis
but are not commercially mature. The efficiency, availability,
reliability and operational requirements of these schemes are
many years from application to present electric power systems.
Storage of heat using water or eutechtic sal ts is a good
system if the energy is to be used ultimately for space heat.
Under rapidly varying wind conditions the energy output of
wind units varies widely. Since utility system loads are quite
stable, the other generation must absorb these wide varia-
tions. The induction generators . also introduce a frequency
stability problem, since they do not operate at a "synchronous"
speed, deriving their excitation from the power system.
These conditions limit the amount of wind driven induction
generation to about 20% at any given moment. This is a very
rough number and will vary with the inherent stability of the
existing system, but will probably never exceed 30%.
Synchronous machines which could carry much more of the
load are prohibitively expensive and not well developed,
reliable systems.
NBISF-426-9523-VII VII-14
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Since storage is a major problem, the electrical energy
generally is generated and consumed in the same instant. At
periods of high wind the loads may be low, while at times of
high load there may be low wind condi tions. This coincidence
factor greatly limits the final percentage of energy which can
be generated with wind equipment.
To an electric utility the wind generation represents only
a savings in fuel and some slight reduction in engine mainte-
nance. A full-sized diesel plant must be maintained because
the wind source may not be available during the system peak.
This benefit is often overestimated by individual consumers
who have their own wind systems because they save the full
billing rate for the electrical power. Actually, they are not
paying for the standby generation, utility equipment and per-
sonnel available to them when the wind doesn't blow. They are
being subsidized by their neighbors.
The communi ties we have studied fall outside of the wind
class map provided. We have assumed Class 5 winds for all
communities.
square meter.
This provides an average energy of 390 Watts per
For this study, two types of wind machines were consid-
ered. Both types are mounted on 60 foot towers and use induc-
tion generators. One unit has seven-foot-diameter blades and a
maximum output of 10 kW, and the other has 20-foot-diameter
blades, with a maximum output of 25 kW. A maximum power pene-
tration of 20 percent was assumed; this means that at any given
moment, not more than 20 percent of the total system load can
be met by wind driven generators. Significant data on the
machines investigated are presented as Table VlI-11.
NBISF-426-9523-VII VII-15
For this study, it was assumed that three ten kilowatt wind
generators would be installed at Larsen Bay during 1982, and
that these plants would be operational during 1983 and would
require replacement every 15 years. A fourth uni t woul d be
brought on line during 1991 and would increase the total
installed capaci ty to 40 kW. The usable wind generation is
presented as Table V II-12. Inspection of Table V 11-12 shows
that the amount of usable wind generation has been assumed to
be constant as long as the installed capacity remains the
same. The amount of usable wind generation would probably
actually increase sl ight ly wi th time; however, th is increase
would probably be minor, and the accuracy of the energy use and
economic analyses would not be enhanced by this refinement.
The estimates presented here are probably high.
E. RECOMMENDED PROJECT PLAN
The recommended project plan for Larsen Bay would consist
of a 270 kW hydroelectric power plant supplemented by diesel
generation. The diesel and fuel storage facili ties would be
installed during 1982 according to the plan outlined above.
The hydroelectric power plant would become functional in late
1984. An on-line date of January 1, 1985, has been assumed for
this study. The annual average energy generation is shown on
Figure VII-2.
The entire diesel capacity (300 kW installed capacity)
would be required as standby and backup power. The hydroelec-
tric generation would be adequate to meet the direct electrical
demand during most of the year; however, during periods between
the end of November and the first of April it would be neces-
sary to supplement the hydroelectric generation with diesel in
order to meet the direct electrical demand. The full capacity
of diesel generation required to meet the direct electrical
demand would still be necessary for emergency use. Since the
diesel engines would not operate as much under this plan as
NBISF-426-9523-VII VII-16
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they would under the base case plan, it was assumed that they
would not need to be replaced for at least 30 years. This would
give the engines and structure the same useful life.
Waste heat recovery would not be included as part of this
plan because the diesels would not operate often enough to
justify the installation of the waste heat equipment.
The average annual energy production for the hydroelectric
power plant would be 1.09 million kWh, compared to a projected
direct electrical demand for electricity of 0.464 million kWh
in 1985 and 0.723 million kWh for the year 2000. The average
annual plant factor would be about 46 percent. Diesel genera-
tion would be required to meet the direct electrical demand for
a small part of the time due to the lack of coincidence between
electrical demand and hydroelectric generation. Hydroelectric
energy not needed to meet the direct electrical demand would be
used for space heating. Appendix G describes space heating
installation and costs for Larsen Bay.
Using the above criteria, the amount of hydroelectric
energy that is available over the study period to meet the
direct electrical demands and the heating demands has been com-
puted on a monthly basis. The results are presented in Tables
VII-9A through VI 1-90. The direct electrical demand and the
mix of demand that could be met by hydro and required supple-
mental diesel generation are presented as Table VlI-10. The
resulting net values of hydroelectric energy used for the
direct electrical demand and the heating demands will be used
in Section IX, Economic Analysis.
Note that the "energy accounting" described above and
presented in Tables VII-9A through 90 assumes that 100 percent
usage can be made of the available hydroelectric energy. This
usage level may not be wholly attainable in practice because of
the unavailability or breakdown of end-use equipment and
NBISF-426-9523-VII VII-17
d istr i but ion lines. Al so, a system making use of all of the
excess hydroelectric energy for heat would not be 100 percent
efficient. However, any error resulting from the assumption of
a 100 percent usage rate would likely be small and would be
counterbalanced because both the projected demand and the
hydroelectric energy output estimates are conservative.
NBISF-426-9523-VII VII-1S
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TABLE VII-1
ELECTRICAL APPLIANCE SATURATION RATES
LARSEN BAY
Consumption Kenai-
per House-Cook Larsen
Appliance Household 1.1 Anchorage 1/ Inlet 1.1 ~~/
(kWh) -------percentage of total households-------
Lights 1,000 100 100
Small Appliances 1,010 100 100
Refrigerator 1,250 100 100
Freezer 1,350 42 56
Water Heater 3,475 100 94
Television 400 156 100+
Video Tape
Recorder 3/ Y 1./
Washer 70 50 85
(Water) (1,050)
Dryer 1,000 71 76
Dishwasher 230 50 31
(Water) (700)
1.1 Values are for 1978 from "Electric Power Consumption for
the Railbelt: A Projection of Requirements," Technical
Appendices, Institute of Social and Economic Resources, May
23, 1980.
~/ The percentage of residences having the listed appliances
is based on estimates from several Larsen Bay residents
usage rate data are not available nor is the mode split
between electrical and other sources of energy known.
1./ Not available.
NBISF-426-9523-7-1
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2
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
TABLE VII-2
UNIT COST AND ENERGY DEMANo..!i
ALASKA
Cost
Location (mills/kWh)
5 Villages (Southeast) 298.7
Haines 2 / 144.3
Juneall2/ 45.7
Juneau-92.2
Ketchikan 58.4
Metlakatla 31.5
Petersburg 123.5
Sitka 49.8
Skagway 133.9
Wrangell 156.3
Yakutat 152.7 AnChOrag~~ 37.5
Anchorag~/ 33.6
Anchorag~ 45.8
Glenallen, Valdez 131. 5
Homer 35.9
Kodiak 149.3
Seward 54.0
Fairbank4j 122.2
Fairbank~ 75.1
Fort Yukon 245.3
Tanana 269.9
48 Villages (AVEC) 422.1
Barrow 129.8
Kotzebue 199.7
Bethel 177.4
Dillingham 151.9
McGrath 233.5
Naknek 174.5
Data obtained from "Alaska Electric Power
1980," Sixth Edition, August 1981, United
of Energy, Alaska Power Administration.
table on page 40, "Energy Sales, Revenue,
were used to develop this table.
Demand
(kWh/Customer)
3,996
5,680
7,775
7,775
8,528
17,981
6,355
8,483
5,879
4,689
7,170
9,124
11,982
14,800
5,890
12,644
5,871
6,694
5,501
10,519
1,669
5,992
2,044
4,395
5,290
4,590
5,000
1,735
5,524
Statistics, 1960-
States Department
Val ues from the
Customers--1980,"
~/ Juneau, Anchorage and Fairbanks are served by more than one
utility. Each listing is for a separate utility.
NBISF-426-9523-7-2
• -
• ...
• -.. ..
• •
• -.. .. .. ..
• ...
• •
• ..
• • .. .. .. ... ..
•
• .. ..
•
• ..
• ..
-
-
....
-
+-
-
....
-
-
-
-
TABLE VII-3
PROJECTED ANNUAL ENERGY DEMAND
LARSEN BAY
Annual Energy Peak
Type of Number of Demand Demand
Year Consumer Customers (1000 kWh) 1./ (kW) --
1980 Residential 48 211 2:..1 70
Small Commercial 5 30 11
School 1 131 55 ~
Total City System 54 372 136
1985 Residential,i./ 75 330 94
Small Commercial 5 36 12
School 1 159 60
Total City System 81 525 166
1990 Residential 83 364 95
Small Commercial 6 40 12
School 1 176 67
Total City System 90 580 174
2000 Total System 92 707 180
2001 Total System 93 723 183
CH2M Hill Study, June 1981. 1/
2/
3/
4/
CH2M Hill study of June 1981 indicates an annual demand of 4400
kWh per consumer. The R. W. Retherford study indicates 4960 kWh
per consumer, annually.
Retherford Associates estimate.
15 to 20 HUD houses are to be built according to the Community
Profile.
NBI-388-9523-VII-3
Month
January
February
March
April
May
June
July
August
September
October
November
December
Totals
TABLE VII-4
MONTHLY LOAD CHARACTERISTICsli
Monthly
Power
Demand
(kW)
165 ~/
151
127
139
127
115
131
144
137
163
163
163
Monthly
Percentage of
Annual Peak
Power DemancJ/
100.0
91.5
77.0
84.2
77.0
69.7
79.4
87.3
83.0
98.8
98.8
98.8
Monthly
Energy
Demand
(kWh)
56,400
50,600
74,400
52,500
50,100
21,000
35,200
44,900
55,500
47,800
52,500
61,600
602,500
Based on 1979 AVEC data for Togiak.
Monthly
Percentage
of Annual
Energy DemancIl./ ,
9.4
8.4
12.4
8.7
8.3
3.5
5.8
7.5
9.2
7.9
8.7
10.2
100.0
1./
~/ This value was changed from 192 kW to 165 kW because it
seemed abnormally high compared to other years. This gives
a 41.7 percent annual load factor.
:l/ Percentages calculated from demand.
NBISF-426-9523-7-4
• ---
•
• ..
• ..
.,
... .. ..
•
• ...
• .. .. ..
• ..
• ...
•
lilt
•
•
lilt
• ..
• ..
-
-
hltlJ
-
-
-
-
Year -
Annual Fuel Oil..!./
(BBL)
Annual Requiremen~
(1000 kWh)
TABLE VII-5
ANNUAL HEATING DEMAND
LARSEN BAY
1980 1985 1990 -~
900 1,200 1,500
1,400 1,870 2,340
2000 2001
2,040 2,090
3,180 3,250
1J 1980, 1990, and 2000 values from CH2M Hill report (1981),
Tables 4-6. Other values interpolated or extrapolated.
~/ Based on 55 gal/BBL, 138,000 BTU/gal, 70% efficiency,
and 3413 BTU/kWh. Values rounded to nearest 10 gallons.
NBISF-426-9523-7-5
Heating
Month
Degre~/
Days -
TABLE VII-6
MONTHLY HEATING DEMANDsl/
LARSEN BAY
Percentage of
Annual Heating
Degree Days 1980 1985 -1990 2000 2001
• ..
•
•
..
•
• ..
---------------1000'kWh ---------------..
January 850 10.9
February 1,070 13.7
March 850 10.9
April 635 8.1
May 595 7.6
June 360 4.6
July 200 2.6
August 235 3.0
September 365 4.7
October 650 8.3
November 800 10.2
December 1,200 15.4
Totals 7,810 100.00
153 204
192 256
153 204
113 151
106 142
64 86
36 49
42 56
66 88
116 155
143 191
216 288
1,400 1,870
255
321
255
189
178
108
61
70
110
194
239
360
2,340
347
436
347
257
242
146
83
95
149
264
324
490
3,180
1/ Based on the number of heating degree days indicated in the
Larsen Bay Community Profile multiplied by the Annual Heating
Demands from Table VII-5.
~/ From the Larsen Bay Community Profile.
NBISF-426-9523-7-6
354
445
354
263
247
149
84
98
153
270
332
501
3,250
,. ..
• ..
• ..
• .. .. .,
., .. .. ..
• ..
• ..
• •
• ..
• •
• •
-
.,..
TABLE VII-7
-ANNUAL ENERGY DEMAND
LARSEN BAY -
Directll
f'''' Electrical Heatin g 2 / Total
Year Demand Demand -Demand .
-------------1000 kWh -------------
.-1980 372 1400 1772
1985 525 1870 2395
1990 580 2340 2920
2000 707 3180 3887
2001 723 3250 3973
.....
-
-
-
1./ From Table VII-3 .
..... ~/ From Table VII-5.
-
NBISF-426-9523-7-7
-
TAlIL~; VII-8
MONTHLY ENERGY DEMAND
LARSEN BAY
1980 985 1990 2000 2001
Percentagel/ Direct Direct Direct Direct Direct
Month
of Annual ElectriC~} Heat / Total ElectriC~} Heat Total Electr\c~} Heat Total ElectriC~} Heat Total ElectriC~} Heat Total ~ ~ _ ~ 1. Demand Demand _ Demand 1.1 Demand Demand _ Demand 1.1 Demand Demand _ ~ 1.1 ~ Demand _ Demand 1.1 Demand
-----------------------------------------------------------------1 ~kWh ----------------------------------------------------------------
January 9.4
February 8.4
March 12.4
April 8.7
May 8.3
June 3.5
July 5.B
August 7.5
September 9.2
October 7.9
Novembe r 8.7
December 10.2
Totals 100.0
Jj From Table VII-4.
~/ From Table VlI-3.
1./ From Table VII-6.
NBISF-426-9523-7-8
I • I 1 I •
35
31
46
33
31
13
22
28
34
29
32
38
372
• •
153
192
153
113
106
64
36
42
66
116
143
~
1400
• 1
188
223
199
146
137
77
58
70
100
145
175
254
1772
, I
49
44
65
46
44
18
31
39
48
41
46
54
525
I •
204
256
204
151
142
86
49
56
88
155
191
288
1870
I I
253
300
269
197
186
104
80
95
136
196
237
~
2395
, .
55
49
72
50
48
20
34
44
53
46
50
59
580
, 1
255
321
255
189
178
108
61
70
110
194
239
360
2340
I •
310
370
327
239
226
128
95
114
163
240
289
419
2920
, ,
66
59
88
61
59
25
41
53
65
56
62
72
707
I I
347
436
347
257
242
146
83
95
149
264
324
490
3180
I •
413
495
435
318
301
171
124
148
214
320
386
562
3887
, ,
68
61
90
63
60
25
42
54
66
57
63
74
723
, I
354
445
354
263
247
149
84
98
153
270
332
501
3250
, I I I
422
506
444
326
307
174
126
152
219
321
395
575
3973
I •
I i
Month
I I
TABLE VII-9A
1980 ENERGY GENERATION, DEMAND, AND USAGE
LARSEN BAY
Directl!
Electrical Hydr~ Direct Use Remaining Heat!! Hydro Used
l
Demand Energy Hydro Energy Hydro Energy Demand For Heat
------------------------------------1000 kWh---------------------------
January
February
March
April
May
June
July
August
September
October
November
December
TOTAL
35
31
46
33
31
13
22
28
34
29
32
38
372
~/ From Table VII-8
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
153
192
153
113
106
64
36
42
66
116
143
216
1,400
o
o
o
o
o
o
o
o
o
o
o
o
o
~/ The proposed hydroelectric project will not go on-line until late 1984 or
early 1985. For the projections, an on-line date of January 1985 has been
assumed.
NBISF-426-9523-7-9A
i
TABLE VII-9B
1985 ENERGY GENERATION, DEMAND, AND USAGE
LARSEN BAY
Direcd/
HYdr(}:./ Us~ Hea t.!./ Elect rical Direct Remaining Hydro Used
Month Demand Energ~ H~dro Energ~ H~dro Energ~ Demand For Heat
" ------------------------------------1000 kWh-------------------------
January 49
February 44
March 65
April 46
May 44
June 18
July 31
August 39
September 48
October 41
November 46
December 54
TOTAL 525
1./ From Table VII-8.
~/ From Table VI-3.
57
48'
34
70
171
170
68
76
131
121
90
54
1,090
49 8 204
44 4 256
34 0 204
46 24 151
44 127 142
18 152 86
31 37 49,
39 37 56
48 83 88
41 80 155
46 44 191
54 0 288
494 596 1,870
~/ Hydro energy that will be used to meet demand currently met
by diesel generation.
NBISF-426-9523-7-9B
8
4
0
24
127
86
37
37
83
80
44
0
530
I. I I I. f I I. f I I. I. f. •• " " " 'I " , I ,. I I I I
Month
January
February
March
April
May
June
July
August
September
October
November
December
TOTAL
1/ From
~ From
TABLE VII-9C
1990 ENERGY GENERATION, DEMAND, AND USAGE
LARSEN BAY
I I
Direct JJ
Electrical Hydr~/ Direct Us~/ Remaining Hea~/ Hydro Used
Demand Energy Hydro Energy Hydro Energy Demand For Heat
------------------------------------1000 kWh-------------------------
55 57 55 2 255 2
49 48 48 0 321 0
72 34 34 0 255 0
50 70 50 20 189 20
48 171 48 123 178 123
20 170 20 150 108 108
34 68 34 34 61 34
44 76 44 32 70 32
53 131 53 78 110 78
46 121 46 75 194 75
50 90 50 40 239 40
59 54 54 0 360 0
580 1,090 536 554 2,340 512
Table VII-8.
Table VI-3.
3/ Hydro energy that will be used to meet energy demand currently met by
diesel generation.
NBISF-426-9523-7-9C
I i
Month
January
February
March
April
May
June
July
August
September
October
November
December
TOTAL
Jj From
TABLE VII-9D
2001 ENERGY GENERATION, DEMAND, AND USAGE
LARSEN BAY
DirectJ}
Electrical Hydro~/ Direct Use~/ Remaining He a t.l/ Hydro Used
Demand Energy Hydro Energy Hydro Energy Demand For Heat
------------------------------------1000 kWh------------------------
68 57 57 0 354 0
61 48 48 0 445 0
90 34 34 0 354 0
63 70 63 7 263 7
60 171 60 111 247 111
25 170 25 145 149 145
42 68 42 26 84 26
54 76 54 22 98 22
66 131 66 65 153 65
57 121 57 64 270 64
63 90 63 27 332 27
74 54 54 0 501 0 --
723 1,090 623 467 3,250 467
Table VII-8.
2/ .-... See Table VI-3 .
1/ Hydro energy that will be used to meet electrical demand currently met by
diesel generation.
NBISF-426-9523-7-9D
I I f I I I I I ,. '1 I I 'I ,. '1 ,. J' " 'I •• •• I I • I I I
-
....
....
'!lfjIII
" ...
....
," ..
y"
....
....
.w.
....
....
....
YEAR
TABLE VII-10
ENERGY DEMAND, GENERATION, AND USAGE
ANNUAL SUMMARY
LARSEN BAY
Total Demand Met Required Supplement
Demand by Hydro Diesel Generat~on
(1000 kWh) 1.1 (1000 kWh) 2/ (1000 kWh) 1... --
1980 372 0 372
1981 403 0 403
1982 433 0 433
1983 464 0 464
1984 494 0 494
1985 525 494 31
1986 536 502 34
1987 547 511 36
1988 558 519 39
1989 569 528 41
1990 580 536 44
1991 593 544 49
1992 605 552 53
1993 618 560 58
1994 631 568 63
1995 644 576 68
1996 656 583 73
1997 669 591 78
1998 682 599 83
1999 694 607 87
2000 707 615 92
2001-34 723 623 100
3/
From Table VII-3. Intermediate values not shown on VII-3
obtained through interpolation .
From Tables VII-9A through VII-9D. Intermediate values not
shown on those tables obtianed through interpolation.
Difference between total demand and demand met by hydro .
NBISF-426-9523-7-10
TABLE VII-11
WIND ENERGY EQUIPMENT DATA
LARSEN BAY
10 kW
Machine
Tower Height (ft) 60
Efficiency (%) 20
Mean Power Output (kW) JJ 3.75
Availability (%) .Y
Annual Usable Energy
Capital Cost ($)
1/ Mean Power Output
90
Generation (kWh) 1.1 27,900
34,000
= (Watts/Meters 2 ) X
(0.7854) X (Diameter 2 ) X
(efficiency)/1000
25 kW
Machine
60
20
7.66
90
60,400
50,000
1./ The availabili ty is the time that the uni t can actually
operate and is limited by breakdowns, maintenance, and
repair.
3/ -Energy = Mean Power Output X Availability.
NBISF-426-9523-7-11
•
---• .. ..
• •
II
• ..
• ..
• ..
• ..
• ..
• ..
• .. .. ..
• .. .. .. .. .. .. ..
• ..
•
...
....
',"j!
....
....
...
....
,..,
YEAR -
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001-
2034
TABLE VII-12
WIND ENERGY USAGE
LARSEN BAY
Peak System Installed Wind
Demand 1./ Ca p acit 2/
(kW) (kW) -
148 0
154 30
160 30
166 30
168 30
169 30
171 30
172 30
174 30
175 40
175 40
176 40
176 40
177 40
178 40
178 40
179 40
179 40
180 40
183 40
Usable Wind
Generatio~/
(MWh) -
0
84
84
84
84
84
84
84
84
112
112
112
112
112
112
112
112
112
112
112
lJ From Table VII-3. Intermediate values obtained by
interpolation.
~/ 10 kW generators. The maximum penetration of asynchronous
wind generators into the system is 20%; therefore, not more
than 20% of the total peak demand can be met by wind at any
time .
~/ From Stone and Webster Report .
NBISF-426-9523-7-12
....
....
"' ..
....
-
iii.
ililil
....
-
....
....
SECTION VIII
PROJECT COSTS
A. GENERAL
The basic assumptions and methodology used to analyze the
total project cost of the Larsen Bay Hydroelectric Project and
a summarized cost estimate are presented in this section. A
more detailed breakdown of the cost estimate methodology is
contained in Appendix D, Detailed Cost Estimate. The appendix
con tains the backup data, incl ud ing the proj ec t construction
schedule and manpower projection.
B. COST ESTIMATING BASIS
Several alternative methods of preparing cost estimates
were considered. The heavy construction estimating method was
determined to be more realistic in this case because of the
nature and location of the project.
The approach taken to prepare the construction cost
estimate was to determine the cost of the required permanent
materials and equipment, construction equipment, and labor.
Due to the location of the project site, it was determined that
all material and equipment would be transported by barge. For
the purposes of this estimate, the material prices at Seattle,
Washington, were determined. Shipping costs by barge from
Seattle to Larsen Bay were used. Material prices were based on
estimating quotes by various manufacturers; commercial harge
transportation companies, based at Seattle, provided shipping
rate quotations for the appropriate commodity classifications.
The skilled labor force was assumed to be brought in by the
contractor . Current wages, based on union scale, incl uding
NBI-411-9523-VIII VlII-l
benefi ts and premium rates for overtime were used. The con-
struction personnel will be housed in a construction camp set
up specifically for this project. Commercial firms that pro-
vide these services in Alaska were contacted for quotes on the
cost of this service. The costs used are based on a cost per
person-day. They are January 1982 pr ices t ha t include set up
and demobilization.
Alaskan contractors were contacted for construction equip-
ment costs, which are current costs based on ownership, opera-
tion, and main tenance. Th is estimate al so assumes that the
equipment will be barged in from Seattle.
As support to the project, commercial air charter fi rms
provided current costs for various sized airplanes suitable for
transporting personnel and supplies.
A construction schedule was prepared to allocate manpower,
material, and equipment costs to each major construction cate-
gory. Allowances were made for associated miscellaneous
acti v i ties requi red for completion of each item. The d irec t
construction cost was determined from the various costs men-
tioned above. Along with the various backup information, these
costs are presented in the Summary of Costs, Table D-6 of
Appendix D.
C. BASE CASE PLAN
Detailed costs were not estimated for the base case plan
because that degree of refinement was not necessary. Costs of
major items are presented in Section IX, Economic Analysis.
D. RECOMMENDED PROJECT COSTS
A rigorous method of cost estimating, known as the heavy-
construction estimating method, was employed to define all
NBI-411-9523-VIII VIII-2
• -
• ..
• -
•
•
• • .. .. ..
•
• •
• •
• •
• ..
• -.. .. ..
•
• .. ..
•
• •
• •
• •
iIiIl
...
.....
.....
-
.. '"
....
to.
.....
....
" ...
project tasks and then determine the time, materials, quanti-
ties, equipment, and skilled personnel required for each
task. Using up-to-date Alaskan data for skilled craft wages,
equipment ownership and use rates, and material and machinery
costs FOB Seattle, the major direct costs for the project --
project mobilization and transportation of materials, equipment
and labor, permanent material, and construction camp costs --
were determined .
The remote nature of the site will require that construc-
t ion mater ial sand equi pmen t be barged from Seattle at the
outset and be returned to Seattle by the same means after
project completion. Barge costs are based on weight and type
of c ommod i ty. Personnel and suppl ies wi 11 be tr ansported by
air.
It was assumed that the crew will be housed in a catered
construct ion camp for the duration of the project. Camp costs
were based on a fixed unit cost per man-day of accommodation.
The camp will be large enough to accommodate necessary fluctua-
tions in the size of the work force .
Subcontracted items included in the estimate are for
const ruc tion of the tr ansmission 1 ine, mov ing the
turbine/generator assembly into place in the powerhouse, and
erection of the prefabricated powerhouse superstructure. A 15
percen t con t ingency fac tor was appl ied to d irec t construct ion
costs, including the subcontracts, except for the transmission
line subcontract, which includes a 10 percent contingency. A
10 percent markup by the prime contractor for handling and
overhead was applied to the transmission line subcontract. The
prime contractor's profit was assumed to be 15 percent and was
applied to all construction costs except the transmission line
subcontract. Engineers' fees for surveying, right-of-way,
geolo~y, design, and construction management were included .
The legal and administrative costs borne by APA were set at
three percent of the direct plus indirect costs .
NBI-411-9523-VIII VII 1-3
Total capital cost of the Larsen Bay Hydroelectric Project
is estimated to be $2,821,400 at January 1982 prices. Prices
for the major components of the construction work and the
indirect costs are presented in Table VIII-I.
NBI-411-9523-VIII VI I 1-4
• ..
• ..
• -• ..
• •
• ..
• • .. ..
• ..
• • .. ..
• ..
• ..
• .. .. ..
• •
• ..
• • ..
•
~.~ TABLE VI II-1
>"",,~ LARSEN BAY
CONSTRUCTION COST
....
Unit
Item Quantit~ Unit Price Amount
....
Mobilizaton and Demobilization LS $321,600
Diversion Dam
'.,~~ Steel Structures 1,100 LB 3.98 4,380
Concrete 10 CY 1113 11,130
Reinforcement 1,150 LB 1. 73 1,980
... $ 17,490
Intake
Offtake Structure 3,500 LB 3.98 13,930 ..... Sediment Structure 8,000 LB 3.98 31,830
Concrete 10 CY 1113 11,130
Reinforcement 1,150 LB 1. 73 1,980
",\!!II-$ 58,870
Penstock
Steel 27 inch dia. 1,425 LF 121 171,840
Fiberglass 27 inch ~ dia. 1,275 LF 76 96,800
Concrete 54 CY 1312 70,850
Excavation 3,030 CY 17 52,270
Backfill 2,730 CY 9 25,120
$416,880
Powerhouse
Prefab Building LS 49,650
Turbine and Generator LS 467,670
Auxiliary Systems LS 123,440
idi. Concrete 111 CY 1113 123,690
Reinforcing Steel 11,370 LB 1. 72 19,610
$784,060
....
Access Road
Excavation and Backfill 600 CY 35 20,720
Gravel fill 630 CY 25 15,940
Culvert 50 LF 70 3,500
Excavation, Rock 4,671 CY 54 254,210
$294,370
.. '"
'oM
NBI-411-9523-8-1
Transmission Line
(Subcontract)
Contingencies -15%
TABLE VlII-1
(Concluded)
(Excluding Subcontract Portion
of Transmission Line)
Contract Cost
Engineering
Right-of-Way and Geology
Design
Construction Management
Owner's Legal and Administrative
TOTAL PROJECT COST
* January 1982.
NBI-411-9523-8-1
Amount
$ 208,980
286 z950
$2,389,200
$ 50,000
175,000
125,000
82 z20Q
$2,821,400*
•
•
• -
• ..
• ...
• •
•
• .. ..
II'
•
• •
• .. -..
• •
• ...
• • ., ..
• ..
• •
• ..
II ..
.....
.....
...
....
....
".l!iilil
"'.
SECTION IX
ECONOMIC ANALYSIS
A. GENERAL
The economic parameters and methodology used to analyze the
economic feasibility of the Larsen Bay Power Project and the
resul ts of the analysis are presented in this section. The
methodology and criteria used for this analysis are in accord-
ance with the standards set forth by APA. The present worth of
the total costs of the base case as developed in Section VII is
compared to the present worth of the total costs of the
proposed hydroelectric project in order to determine the more
advantageous scheme for development. Based on this analysis,
the proposed hydroelectric project is the more favorable
alternative and it appears to be feasible.
B. PROJECT ANALYSIS PARAMETERS
The assumptions that form the basis for this analysis are
founded to as great an extent as possible on the APA standard
criteria. Wherever necessary, additional assumptions were
based on the best available information and on experience •
The data previously developed in Section VII, Project
Energy Planning, and Section VIII, Project Costs, are exten-
sively utilized in this analysis.
The planning period and the economic evaluation period both
begin with January 1982. The hydroelectric project is assumed
to be on-line by January 1985, and the analysis extends 50
years beyond that time. The last year of the analysis is 2034
and the length of the evaluation period is 53 years. The
NBI-388-9523-IX IX-1
planning period for meeting future demands assumes a leveling
of growth in 20 years, and it includes the year 2001.
For purposes of this analysis, no inflation was assumed.
The values of diesel fuel and lubricating oil were escalated at
2.6 percent annually to account for the escalation of oil
prices at a rate greater than inflation. The values were
escalated for the duration of the planning period, wi th the
last escalation occurring in the year 2001. The costs were
held constant at the 2001 value for the remainder of the period
of economic evaluation through 2034.
All annual cash flows were discounted to January 1982 at
three percent interest.
The interest rate for all amortization and sinking funds
was assumed to be three percent. This and the above assump-
tions are in accordance with the APA criteria.
The economic life of the hydroelectric project was assumed
to be 50 years. The economic project life for diesels was
assumed to be 15 years for the engines and 30 years for the
structure for the base case and 30 years for both the engines
and structure for the hydroelectric al terna ti ve; the diesels
were given a longer life for the hydroelectric al ternative
because they would operate significantly less often than they
would for the base case. The diesel engine life for the base
case was reduced to 15 years from the 20 year period that is
APA standard criteria because the machines that would be
installed here would be small, high speed machines that would
wear out faster than large uni ts. The installation proposed
for Larsen Bay would use diesel engines that operate at 1800
rpm, as apposed to somewhat larger machines common at similar
installations that operate at 1200 rpm. The 15 year economic
life is the standard criteria used by the Rural Electrification
Agency.
NBI-388-9523-IX IX-2
• -
• -
• -..
•
• ..
• -• •
II
•
• ..
• ..
• •
• -• ..
• -•
• ..
• ..
• •
• •
ill.
....
.....
...
...
....
.....
....
....
....
....
....
Operation and maintenance costs were assigned to the year
during which they would occur.
Capital costs were assigned to the year in which they would
occur. They were assumed to be equal to the total investment
cost because the construction periods for all items included in
the analysis were less than one year.
struction was included. The first
No interest during con-
amortization payment was
shown in the year following the capital cost .
Amortization costs, operation and maintenance costs, and
benefits were assumed to occur at the end of the year and were
shown in the year that they actually occurred .
Replacement costs were handled by the use of a sinking
fund. Replacement sinking funds were assumed to occur in per-
petuity.
All costs that were common to both plans, such as local
distribution costs, were excluded. It will be necessary to
bui ld a distribution system for either al terna t i ve. The cost
of installing the transmission system would probably be about
$80,000 plus $1500 per residential service and $5000 per
commercial service •
The effects of installing waste heat recovery were con-
sidered separately and applied as a reduction in cost where
appropriate. The benefit for space heating for the hydroelec-
tric alternative case also was treated separately .
C. BASE CASE ECONOMIC ANALYSIS
The base case plan was originally formulated as diesel
generation supplemented by waste heat recovery. This plan was
modified to include wind generation. The original base case
NBI-388-9523-IX IX-3
•
•
•
analysis is presented below, and it is followed by the wind -
generation analysis.
1. Original Plan
The base case plan was analyzed to determine the present
worth of the total cost of the base case plan over the entire
period of analysis. The cost of the base case plan would be
the sum of the costs of building and replacing the diesel gen-
eration system, insurance, operation and maintenance, lubrica-
tion oil, and fuel oil. These costs were all assigned to the
year of their occurrence, and the total annual cost of the
existing system was calculated for each year of the period of
economic evaluation. These annual costs were then discounted
at three percent interest to January 1982. They were then
summed to find the total present worth of the base case alter-
native.
The costs of replacing and expanding the plant were assumed
to be the cost of replacing the diesel engines every 15 years
at a cost of $150,000 and replacing the entire plant every 30
years at a cost of $400,000. These costs are consistent with
the current market.
The cost of insuring the power plant was assumed to be
$0.83 per $100 of replacement value. This rate represents
current insurance rates for Alaska. The plant was assumed to
have a replacement value of $400,000.
The costs of operation and maintenance reflect experience
and they were assumed to be the sum of the maintenance cost,
calculated as $17 per megawatt-hour of energy produced, and the
cost of an operator, which was taken as $60,000 per year.
The total cost of lubrication oil was calculated from the
unit cost of lubrication oil and the amount of lubrication oil
NBI-388-9523-IX IX-4
---•
•
•
• •
• •
• •
• •
• • ..
•
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• ---• ..
-
• •
• •
• •
.,
....
-
.....
....
.....
, ...
required. The lubrication oil rate of use was assumed to be
0.60 gallons per megawatt-hour and the cost of lubrication oil
was assumed to be $3.95 per gallon for January 1982. The costs
of operation and maintenance are based on experience with
similar projects in Alaska. The cost of lubrication oil was
also escalated at 2.6 percent for the duration of the planning
period to be consistent wi th treatment of all petroleum pro-
ducts.
The total cost of fuel oil was calculated from the cost per
gallon of fuel oil and the anticipated rate of fuel oil con-
sumption. The average energy value of fuel oil was taken as
138,000 Btu/gallon and the average overall efficiency of the
diesel genera tors was assumed to be 22 percent; using these
criteria, one gallon of oil will produce 9.0 kilowatt-hours of
electrici ty. The fuel oil cost for King Cove was established
at $1.78 per gallon for January 1982 and escalated according to
the previously mentioned criteria for real price changes.
The annual costs over the project economic study period of
the base case diesel generation for operations and maintenance,
lubrication oil, and fuel oil, and replacement are presented in
Tables IX-1, IX-2, IX-3, and IX-4, respectively, and combined
in Table IX-5 to show the annual cost for the base case for
each year of economic evaluation. These annual costs were dis-
counted to January 1982 at three percent interest .
After the annual cost of the base case plan was calculated,
the savings possible from waste heat recovery were estimated.
The total amount of heat available annually for recovery would
be approximately equivalent in heat output to the amount of
electricity generated annually by the plant. Waste heat
recovery at Larsen Bay would be from the cooling water jackets
and from the oil cooling system. Waste heat recovery from the
exhaust would not be practical at this site. Al though waste
heat recovery from the diesel cooling systems is highly
NBI-388-9523-IX IX-5
efficient, only about 60 percent of the total waste heat avail-
able would have an end use in 1982 as marketable heat because
of heat generated during the summer when it is not needed for
institutional users such as the school. The increase in total
generation and total demand over the planning period was
assumed to result in an annual growth rate for the amount of
usable waste heat of about 1.5 percent. The amount of waste
heat that would be usable, and the growth rate for usable waste
• •
• ---
• •
• •
heat, are based on experience with similar projects in _
Alaska . Data on installations of this type are not avai lable
and projections of usable waste heat are difficult to quantify;
however, the projections presented herein are probably conserv-
ative.
The costs associated with waste heat recovery are the cost
of installation and the cost of operation and maintenance. The
-• •
• ..
•
installa t ion cost includes the cost of the equipment in the -
powerhouse, the cost of insulated, buried pipes from the power-
house to the point of use, and the cost of installing radiators
at the points of use. The equipment used for waste heat
recovery from the water jackets and cooling oil do not have any
moving parts and should last for the entire period of economic
evaluation. The only required replacement costs would occur
when the diesel power plants are replaced; at that time, it
• • ..
•
• •
would be necessary to replace the heat recovery equipment •
located in the powerhouse. The heat would be available for use _
up to 2000 feet from the power plant.
The initial cost of the waste heat recovery system would be
$143,000, and the replacement cost would be about $60,000 every
15 years. The operation and maintenance of the system would be
very minimal and probably would not exceed $1,000 per year.
Using these data, the annual waste heat recovery costs are pre-
sented in Table IX-6.
NBI-388-9523-IX IX-6
• •
• •
• •
•
•
• •
• •
"'.,,'
.~ ..
" ..
The annual savings from waste heat recovery for each year
of operation were calculated as a credit for the oil displaced
by waste heat recovery. The result was reduced by the annual
costs from Table IX-6 to yield an annual savings stream for the
project, as presented in Table IX-7.
The annual base case diesel generation costs and present
worth of these costs are presented in Table IX-8 along with the
waste heat recovery savings and the present worth of the
savings. As shown, the total January 1982 present worth of the
costs of the base case would be $7,532,100 and the present
worth of the waste heat recovery savings would be $807,000,
yielding a net present worth of the base case of $6,725,100.
2. Wind Generation Plan
The possibility of installing wind-powered generators as
part of the base case was also considered. Wind powered
generation is discussed in detail in Section VII, including
installed capacities and energy generation. (This data is from
the 1982 Stone and Webster Report -See Section VII.)
The benefi ts attributable to wind generation would be a
reduction in the amount of fuel consumed by the diesel genera-
tors, and a slight decrease in the lubrication and maintenance
costs associated wi th the diesel generation. These costs are
summarized in Tables IX-lA, IX-2A and IX-3A which are included
behind Table IX-21. These tables are combined in Table IX-4A.
The costs of installing, replacing, and maintaining the diesels
would not be affected by the addition of wind generation
because the full standby diesel capacity would always be
required, the diesels would not have enough reduction in
operation to
would receive
increase thei r useful lives, and the opera tor
the same salary regardless of how often the
diesels operate.
NBI-388-9523-IX IX-7
The cost of 10 kW wind turbines and generators was assumed
to be $34,000 each, installed. The operation and maintenance
cost for the wind turbines was assumed as five percent of the
capital cost. The wind turbines were assumed to have a useful
life of 15 years. A summary of costs associated wi th this
installation is presented as Table IX-5A.
The credi ts for reduction in diesel generation were then
adjusted by the cost of wind generation to yield the annual
credit attainable from wind generation. This credit was
discounted to January 1982 at three percent interest. The
present worth of the wind generation credit is $330,400. This
present worth is summarized in Table IX-6A.
D. RECOMMENDED HYDROELECTRIC PROJECT ECONOMIC ANALYSIS
• ..
• ..
• -
•
•
•
• •
• • .. ..
• The recommended hydroelectric project plan was analyzed to •
determine the present worth of the total cost of the recom-
mended project over the period of economic evaluation. The
cost of the recommended project would include the costs of
building, replacing, operating and maintaining the new hydro-
electric development and the costs associated with building and
replacing the diesel system, insurance, operation and mainten-
ance, lubrication oil, and fuel oil for the diesel system. It
would be necessary to maintain sufficient diesel capaci ty to
meet projected power demands in the event of an outage of the
hydroelectric plant. This has been previously discussed in
Sec t ion VI I and it is ill ust rated in Table IX-14. The diesel
capacity would also be required at times when the demand on the
• ..
• .. --•
• ..
system is greater than can be met by the hydroelectric genera-•
tion. -
The cost of the diesel supplement to hydroelectric genera-
t ion was calculated in the same manner as for the base case,
with the following differences: the diesels supplied only the
demand that could not be met by the hydroelectric plant; the
NBI-388-9523-IX IX-8
• ..
• -
• -
• ..
'M'
...
....
....
....
,. ...
diesel engines would only need to be replaced every 30 years
instead of every 15 years; only one-half of the operator's
salary would be assigned to the cost of the diesel, the other
half being assigned to the hydroelectric project; and the
diesels would not operate often enough to justify waste heat
recovery.
The annual costs over the project economic study period of
the supplemental diesel system for the recommended hydroelec-
tric project for operation and maintenance, lubrication oil and
fuel oil are presented in Tables IX-9, IX-10, IX-11,
respectively. Those costs are combined in Table IX-12 to
present the annual cost for the supplemental diesel generation
for each year of the economic evaluation .
The capital cost of $2,821,400 for the hydroelectric power
plant was amortized at three percent over a period of 50 years
from the on-line date of the power project. The cost of the
operation and maintenance was taken as 1.5 percent of the con-
tract cost; this is based on U.S. Bureau of Reclamation
practice.
Two replacement costs were considered for the hydroelectric
power plant: the cost of replacing the turbine runner after 25
years of operation, and the cost of replacing the transmission
line that would tie the plant to the village distribution
system every 30 years. The economic lives used for both the
runner and transmission lines are based on experience and are
conserva t i ve. The cost of replacing the runner was estimated
as $80,000, and the cost of replacing the lines was estimated
as $208,980. Sinking funds were established to meet these
costs .
The annual costs of the hydroelectric portion of the recom-
mended hydroelectric project are presented in Table IX-13. This
table includes the amortization, operation and maintenance, and
NBI-388-9523-IX IX-9
replacement costs. These costs are then combined with the
annual costs for the supplemental diesel system from Table IX-
12 and presented as the combined diesel and hydroelectric costs
in Table IX-14.
The proposed hydroelectric power plant would also generate
power in excess of the village's direct demand during certain
times of the year. The hydroelectric energy that would be
available in excess of the village's direct electrical demand
could be used for space heating in the village. The distribu-
tion of hydroelectric generation is addressed in Chapter VII.
The space heating energy available from hydroelectric gen-
eration would be equivalent to one gallon of oil for every 28.3
kilowatt-hours of available electricity. This conversion
factor is based on an assumed average energy value for oil of
138,000 Btu/gallon and 70 percent ef f iciency. The values for
displaced energy used are from Tables VII-9A to VII-9D.
The use of electricity for space heating would be
controlled automatically in order to take advantage of as much
excess electricity as possible. The system design and cost
estimate are included as Appendix G. The Kodiak Island
Authority should be informed of space heating plans.
The annual savings for the hydroelectric energy used for
space heating are presented in Table IX-15. This table indi-
cates the annual hydroelectric energy available for the heat
demand, the equivalent amount and cost of the fuel oil dis-
placed, annual cost of the electric space heating, and the
resulting net annual savings.
The present worth of the recommended hydroelectric project
cost is presented in the Table IX-16 summary as $5,941,700.
This table also shows that the present worth of the fuel oil
savings in using excess hydroelectric energy to meet space
heating demand would be $1,006,100.
NBI-388-9523-IX IX-10
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•
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lit
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• •
E. ECONOMIC COMPARISON OF PROJECTS
The base case plan and the recommended hydroelectric proj-
ect plan can be compared on the basis of the present worth of
the total cost of each plan. Both plans were formulated to
satisfy the same energy demand and the plan having the lower
present worth of costs would be the more advantageous plan for
development.
In addition to the cost of diesel generation and the cost
of the hydroelectric project, economic benefi ts are available
from waste heat recovery, wind generation and from use of
excess hydroelectric power for space heating. The actual plans
as presented herein consider the waste heat recovery and wind
generation as part of the base case plan, and the space heating
credi t as part of the recommended hydroelectric project. For
purposes of determining the relative economic merit of the
projects, with emphasis on the hydroelectric project, the costs
associated with the hydroelectric project can be considered as
costs and the costs of the present system, that would be
avoided by installation of the hydroelectric project, can be
considered to be benefits. The cred i ts avai lable from waste
heat recovery and wind generation were considered as reductions
in the cost of the base case and the space heating credit was
considered to be an increase in the cost of the base case.
A summary of the present worth of the costs and benefits
outlined above is presented as Table IX-17. The benefits
associated wi th the project are the cost of the base case,
minus the credits from waste heat recovery and wind generation,
plus the space heating credit. The cost associated wi th the
project is the cost of the recommended hydroelectric project,
including the cost of supplemental diesel generation.
NBI-388-9523-IX IX-ll
Benefit/cost ratios for the project are presented as Table
IX-18. The benefit/cost ratio for the base case only is
1.268. The benefit/cost ratio, considering the base case
diesel costs, including waste heat recovery as a benefit, is
1.132. If the benefi t is adjusted by the wind generation
credit, the benefit/cost ratio is 1.067. If the benefit is
adjusted for the wind energy credit and the space heating
credit, the benefit/cost ratio is 1.237.
F. UNIT COSTS AND PROJECT TIMING
As requested by the Alaska Power Authority, the unit energy
cost of the base case and recommended hydroelectric project
plans were calculated on an annual basis. These values are
presented in Tables IX-19 and IX-20, and are shown graphically
on Figure IX-I.
The optimum timing for project development would occur when
the unit costs of the diesel generation system exceeds the unit
cost of the proposed hydroelectric power project. Because
actual costs are important for this comparison, the space
heating credi t is shown as an adjustment to the recommended
hydroelectric project cost. The annual unit costs for the two
schemes are shown with and without the adjustment for this
credit.
Inspection of Figure IX-1 reveals a number of
discontinuities. These discontinuities are due to large
changes in the net annual cash flow of each configuration that
are caused by capital expenses or increases in generating
capacity. A discontinuity showing an increase in the unit cost
of energy indicates that the annual cost of a capital
expenditure exceeds the annual value of the increase in
generation, if any, resul ting from that cost. This type of
discontinuity normally accompanies a major investment, such as
installation of a hydroelectric facility or expansion of diesel
NBI-388-9523-IX IX-12
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•
•
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•
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• ..
• •
• •
• •
• •
• •
"o,!'
.....
...
.....
.1
plant capacity; this type of discontinuity would also accompany
expenses associated with the power system that do not result in
increased generation, such as construction of fuel storage
facilities.
Downward discontinuities on Figure IX-1 indicate
expenditures that result from an annual increase in generation
having greater value than the annual cost of the increase.
This si tua t ion resul ts from the installation of conservation
methods, such as waste heat recovery.
The general downward sloping trend of the unit cost of the
various levels of the hydroelectric project are the result of a
gradual increase, over time, of the amount of hydroelectric
energy that can be used. These lines indicate an advantage
associated with hydroelectric projects; although the initial
cost of a project of this nature is high, the variable annual
costs are low.
The general upward trend of the base case unit annual cost
is the result of the increase in total demand for electricity
and the increase in the cost of oil. For the base case plan,
increasing demand must be met primarily by diesel generation,
giving this plan a high variable annual cost .
For the Larsen Bay Project, no cost of electricity is shown
prior to 1983. This is because the village does not have an
existing system. The costs of the five different levels of the
project are shown as parallel lines for 1983 and 1984; the cost
of both hydroelectric cases is the same but is less than the
base case without space heating or wind credits because the
newly installed diesels have been given a longer life than they
were for the base case plan. The cost of the hydroelectric
project jumps upward at the start of 1985 due to the cost of
the hydroelectric project; this cost is also shown adjusted
downward for the inclusion of the space heating credit.
NBI-388-9523-IX IX-13
The base case alternative including the wind energy credit
shows a decrease in 1991 due to increased capacity. The
decrease in the cost of the base shown for 1998 is due to the
fact that the sinking fund for the first interim engine
replacement was only for 15 years and would be for 30 years
after 1998; see Table IX-4. The decrease in the cost of all
plans, shown for 2001, results from the retirement of the debt
from the construction of fuel storage facilities.
As shown on Figure IX-I, the base case cost would exceed
the recommended hydroelectric project cost by the time the
recommended hydroelectric project could be brought on line.
NBI-388-9523-IX IX-14
•
•
• --..
• •
• ..
•
•
• •
• •
• -• -• ..
• •
• •
• -• •
• •
• •
• ..
• •
.... '
"",
....
-.
riO·"
"....,fI
... ""w
.. "
.....
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, ....
... .,
TABLE IX-1
BASE CASE
DIESEL OPERATION AND MAINTENANCE COSTS
LARSEN BAY
Annual
Energy..!..! Annual
Production Maintenancedi Operation.l! Cost
Year (1000 kWh) ($) ($) ($)
1982
1983 464 7,900 60,000 67,900
1984 494 8,400 60,000 68,400
1985 525 8,900 60,000 68,900
1986 536 9,100 60,000 69,100
1987 547 9,300 60,000 69,300
1988 558 9,500 60,000 69,500
1989 569 9,700 60,000 69,700
1990 580 9,900 60,000 69,900
1991 593 10,100 60,000 70,100
1992 605 10,300 60,000 70,300
1993 618 10,500 60,000 70,500
1994 631 10,700 60,000 70,700
1995 644 10,900 60,000 70,900
1996 656 11,200 60,000 71,200
1997 669 11,400 60,000 71,400
1998 682 11,600 60,000 71,600
1999 694 11,800 60,000 71,800
2000 707 12,000 60,000 72,000
2001 723 12,300 60,000 72,300
2002-34 723 12,300 60,000 7 2,300
~/ From Table VII-10.
~/ $17 per megawatt-hour. Values rounded to nearest $100.
~ $60,000 for operators salary .
NBI-411-9523-IX-3
AnnuallJ
Energy
Production
Year (1000 kWh)
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002-34
464
494
525
536
547
558
569
580
593
605
618
631
644
656
669
682
694
707
723
723
TABLE IX-2
BASE CASE
DIESEL LUBRICATION OIL COSTS
LARSEN BAY
Lubrication~/
Oil
(gallons)
278
296
315
322
328
335
341
348
356
363
371
379
386
394
401
409
416
424
434
434
Lubricatiord/
Oil Cost
($/gallon)
4.05
4.16
4.27
4.38
4.49
4.61
4.73
4.85
4.98
5.11
5.24
5.37
5.51
5.66
5.81
5.96
6.11
6.27
6.43
6.43
lJ From Table VlI-10.
~/ 0.6 gallons per megawatt-bour.
1/ Escalated at 2.6 percent annually.
~/ Values rounded to nearest $100.
NBI-411-9523-IX-4
Lubrication~./
Oil Cost
($)
1,100
1,200
1,300
1,400
1,500
1,500
1,600
1,700
1,800
1,900
1,900
2,000
2,100
2,200
2,300
2,400
2,500
2,700
2,800
2,800
•
•
• -
• ---• -• -• •
• •
• •
• .. ..
•
• •
• •
• -•
•
• •
• •
• •
• •
-......
....
....
"'/'#
"''at;''
.....
....
....
TABLE IX-3
BASE CASE
DIESEL FUEL OIL COSTS
LARSEN BAY
Annual..!! Equivalent.~/ Energy Fuel Fuel
Production Oil Oil Cost Oil Cost~/
Year (1000 kWh) (gallons) -)
($/gallon) ($)
1982
1983 464 51,600 1.82 93,900
1984 494 54,900 1.87 102,700
1985 525 58,300 1.92 111,900
1986 536 59,500 1.97 117,200
1987 547 60,800 2.02 122,800
1988 558 62,000 2.07 128,300
1989 569 63,200 2.12 134,000
1990 580 64,400 2.18 140,400
1991 593 65,900 2.23 147,000
1992 605 67,200 2.29 153,900
1993 618 68,700 2.35 161,400
1994 631 70,100 2.41 168,900
1995 643 71,500 2.48 177,300
1996 656 72,900 2.54 185,200
1997 669 74,300 2.61 193,900
1998 682 75,800 2.67 202,400
1999 694 77,100 2.74 211,300
2000 707 78,500 2.82 221,400
2001 723 80,300 2.89 232,100
2002-34 723 80,300 2.89 232,100
..!! From Table VlI-10.
~/ 111.1 gallons per megawatt-hour. Based on 138,000
Btu/gallon, 3,413 Btu/kWh, and 22 percent efficiency.
Values rounded to nearest 100 gallons.
1/ Values rounded to nearest $100.
NBI-411-9523-IX-5
New Plantl/
Schedule of Amortization~/ Investment
Year ( $) ($)
1982 400,000
1983 20,400
1984 20,400
1985 20,400
1986 20,400
1987 20,400
1988 20,400
1989 20,400
1990 20,400
1991 20,400
1992 20,400
1993 20,400
1994 20,400
1995 20,400
1996 20,400
1997 20,400
1998 20,400
1999 20,400
2000 20,400
2001 20,400
2002 20,400
TABLE IX-4
BASE CASE
DIESEL SCHEDULE OF INVESTMENT
LARSEN BAY
Fue 1 Tank-~/
Schedule of
Investment
( $)
150,000
Amortization~/
( $)
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
10,100
Replace.~/
Engines
Schedule of
Investment
($)
150,000
2003-34 400,000 20,400 150,000
Jj
21
Replace entire plant every 30 years at a cost of $400,000.
$400,000 amortized for 30 years at 3 percent in perpetuity.
New plants in
Annuall/ Sinkin~1
Fund
Investment
Cost
( $) $
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
8,100 38,600
3,200 33,700
3,200 33,700
3,200 33,700
3,200 33,700
3,200 33,700
3,200 23,600
1982 and 2012.
~I
41
One-time cost for two 50,000 gallon fuel storage tanks and protective dike.
$150,000 amortized for 20 years a 3 percent.
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III
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• -
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• •
~I Interim engine replacement. Replace engines in 1997 and 2027. Engine life is 15 years instead
of 20 years because they are small high speed engines. II
~I $150,000, 15 years at 3 percent, then $150,000 for 30 years at 3 percent in perpetuity.
II Values rounded to nearest $100.
NBI-411-9523-IX-4a
..
• ..
• •
£ • • I " I t • i f
i t .. II; II; " • , .. •
TABLE IX-5
BASE CASE
DIESEL COSTS
LARSEN BAY
Firm!/ Schedule.Y AnnuaJ21
Operation.!!
Insuranc~ and
Capacity of Investments Cost Maintenance
Year (kW) ($) ($) ($) ($) --
1982 300 550,000
1983 300 38,600 3,300 67,900
1984 300 38,600 3,300 68,400
1985 300 38,600 3,300 68,900
1986 300 38,600 3,300 69,100
1987 300 38,600 3,300 69,300
1988 300 38,600 3,300 69,500
1989 300 38,600 3,300 69,700
1990 300 38,600 3,300 69,900
1991 300 38,600 3,300 70,100
1992 300 38,600 3,300 70,300
1993 300 38,600 3,300 70,500
1994 300 38,600 3,300 70,700
1995 300 38,600 3,300 70,900
1996 300 38,600 3,300 71,200
1997 300 150,000 38,600 3,300 71,400
1998 300 33,700 3,300 71,600
1999 300 33,700 3,300 71,800
2000 300 33,700 3,300 72,000
2001 300 33,700 3,300 72,300
2002 300 33,700 3,300 72,300
2003-34 300 550,000 23,600 3,300 72,300
The largest unit is omitted when calculating firm capacity.
From Table IX-4.
i t 1 .. , ..
Lubr icat ion..i/
Oil
($)
1,100
1,200
1,300
1,400
1,500
1,500
1,600
1,700
1,800
1,900
1,900
2,000
2,100
2,200
2,300
2,400
2,500
2,700
2,800
2,800
2,800
1/
2/
3/
4/
5/
6/
Replacement cost is $400,000. Insurance cost is $0.83 per $100 replacement value.
Table IX-1.
Table IX-2.
Table IX-3.
NBI-411-9523-IX-2
l t
FueI§l Annual
Oil Cost
($) ($)
93,900 204,800
102,700 214,200
111,900 224,000
117,200 229,600
122,800 235,500
128,300 241,200
134,000 247,200
140,400 253,900
147,000 260,800
153,900 268,000
161,400 275,700
168,900 283,500
177,300 292,200
185,200 300,500
193,900 309,500
202,400 313,400
211,300 322,600
221,400 333,100
232,100 344,200
232,100 344,200
232,100 334,100
Year
Schedule
of Capital
Investment
($)
1982 143,000
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001-34
TABLE IX-6
BASE CASE
WASTE HEAT RECOVERY ANNUAL COSTS
LARSEN BAY
Schedule o~1
Replacement Sinkin~
Amortizationll Investment Fund
($) ($) ($)
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
5,500
60,000
120,000
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
3,200
II 52 years at 3 percent. Rounded to nearest $100.
Operation
and
Maintenance
($)
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
Annual
Cost
($)
0
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
9,600
1/ Replace diesel engines every 15 years. Replace equipment in plant in
1997, 2012, and 2027. See Table IX-4.
• -
• -
• ..
• ..
•
•
• .. ..
• ..
•
• ..
• ..
• • .. ..
• ---
• .. ..
•
•
1V Sinking fund $60,000, 15 years at 3 percent, in perpetuity. Rounded to •
nearest $100.
NBI-411-9523-IX-5a
• •
• •
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....
....
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... "
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....
."
......
.....
TABLE IX-7
BASE CASE
WASTE HEAT RECOVERY SAVINGS
LARSEN BAY
Oil"!! Oi :t..Y Annua0
Net
Cred i t..~./ Annual
Equivalent Cost Cost Savings
Year (~allons) ($/~allon) ($) ($) ($)
1982 0 0 0 0
1983 13,200 1.82 24,000 9,600 14,400
1984 13,400 1.87 25,100 9,600 15,500
1985 13,600 1.92 26,100 9,600 16,500
1986 13,800 1.97 27,200 9,600 17,600
1987 14,000 2.02 28,300 9,600 18,700
1988 14,200 2.07 29,400 9,600 19,800
1989 14,400 2.12 30,500 9,600 20,900
1990 14,600 2.18 31,800 9,600 22,200
1991 14,900 2.23 33,200 9,600 23,600
1992 15,100 2.29 34,600 9,600 25,000
1993 15,300 2.35 36,000 9,600 26,400
1994 15,500 2.41 37,400 9,600 27,800
1995 15,800 2.48 39,200 9,600 29,600
1996 16,000 2.54 40,600 9,600 31,000
1997 16,300 2.61 42,500 9,600 32,900
1998 16,500 2.67 44,100 9,600 34,500
1999 16,700 2.74 45,800 9,600 36,200
2000 17,000 2.82 47,900 9,600 38,300
2001 17,300 2.89 50,000 9,600 40,400
2002-34 17,300 2.89 50,000 9,600 40,400
l/ Escalated at 1.5% annually. See page IX-5.
2/ Escalated at 2.6% annually.
~/ Rounded to nearest $100.
~/ Includes Replacement Sinking Fund, Amortization, and
Operation and Maintenance from Table IX-6 .
NBI-411-9523-IX-6
• • -TABLE IX-8 -
BASE CASE •
SUMMARY -LARSEN BAY -Annual..!..! AnnuaL~./
Presen0
Waste Heat..i/
Presen0 • Energy Diesel Recovery
Demand Cost Worth Savings Worth .. Year (1000 kWh) ($) ($) ($) ($) •
1982
1983 464 204,800 193,000 14,400 13,600 •
1984 494 214,200 196,000 15,500 14,200 •
1985 525 224,000 199,000 16,500 14,700
1986 536 229,600 198,100 17,600 15,200 ..
1987 547 235,500 197,200 18,700 15,700 •
1988 558 241,200 196,100 19,800 16,100
1989 569 247,200 195,100 20,900 16,500 ..
1990 580 253,900 194,600 22,200 17,000 •
1991 593 260,800 194,100 23,600 17,600
1992 605 268,000 193,600 25,000 18,100 •
1993 618 275,700 193,400 26,400 18,500 •
1994 631 283,500 193,100 27,800 18,900
1995 644 292,200 193,200 29,600 19,600 ..
1996 656 300,500 192,900 31,000 19,900 ..
1997 669 309,500 192,900 32,900 20,500
1998 682 313,400 189,600 34,500 20,900 ..
1999 694 322,600 189,500 36,200 21,300 • 2000 707 333,100 190,000 38,300 21,800
2001 723 344,200 193,600 40,400 22,400 ..
2002 723 334,200 185,000 40,400 21,700 -2003-34 723 334,100 3,662,100 40,400 442,800 • TOTALS 7,532,100 807,000 • ..
•
•
1/ • From Table VII-10.
2/ • From Table IX-5. •
3/ January 1982. Discounted at 3%. Present worth factors
accurate to four decimal places. Rounded to nearest $100. • -4/ Table IX-7. • NBI-411-9523-IX-1 •
• •
{,lIf/Il
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TABLE IX-9
RECOMMENDED HYDROELECTRIC PROJECT
DIESEL OPERATION AND MAINTENANCE COSTS
LARSEN BAY
Annual.!!
Energy Maintenanc~ Operation1!
Annual
Production Cost
Year (1000 kWh) ($) ($) ($) -
1982
1983 464 7,900 60,000 67,900
1984 494 8,400 60,000 68,400
1985 31 500 30,000 30,500
1986 34 600 30,000 30,600
1987 36 600 30,000 30,600
1988 39 700 30,000 30,700
1989 41 700 30,000 30,700
1990 44 700 30,000 30,700
1991 49 800 30,000 30,800
1992 53 900 30,000 30,900
1993 58 1000 30,000 31,000
1994 63 1,100 30,000 31,100
1995 68 1,200 30,000 31,200
1996 73 1,200 30,000 31,200
1997 78 1,300 30,000 31,300
1998 83 1,400 30,000 31,400
1999 87 1,500 30,000 31,500
2000 92 1,600 30,000 31,600
2001 100 1,700 30,000 31,700
2002-34 100 1,700 30,000 31,700
~/ Required supplemental diesel generation from Table VII-10.
~ $17 per megawatt hour. Rounded to nearest $100.
~/ One-half of operator's salary after hydro plant goes on-
line in 1985.
NBI-411-9523-IX-10
TABLE IX-10
RECOMMENDED HYDROELECTRIC PROJECT
DIESEL LUBRICATION OIL COSTS
LARSEN BAY
Annual..!! Lubrication~/ Lubricatiord! Lubrication!! Energy
Production Oil Oil Cost Oil Cost
Year (1000 kWh) (gallons) ($/~allon) ($)
1982
1983 464 278 4.05 1,100
1984 494 296 4.16 1,200
1985 31 19 4.27 100
1986 34 20 4.38 100
1987 36 22 4.49 100
1988 39 23 4.61 100
1989 41 25 4.73 100
1990 44 26 4.85 100
1991 49 29 4.98 100
1992 53 32 5.11 200
1993 58 35 5.24 200
1994 63 38 5.37 200
1995 68 41 5.51 200
1996 73 44 5.66 200
1997 78 47 5.81 300
1998 83 50 5.96 300
1999 87 52 6.11 300
2000 92 55 6.27 300
2001 100 60 6.43 400
2002-
2034 100 60 6.43 400
l/ Required supplemental diesel generation from TableVlI-10.
~ 0.6 gallons per megawatt-hour.
1/ Escalated at 2.6 percent annually.
jj Rounded to nearest $100.
NBI-411-9523-IX-11
• ---
•
-
• -• -
• •
• ..
•
• ..
• -• -• •
• •
•
•
• •
• ..
• •
• •
, .. ,
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.....
TABLE IX-11
RECOMMENDED HYDROELECTRIC PROJECT
DIESEL FUEL OIL COSTS
LARSEN BAY
Annual..!.!
Equivalene/ Fuel Oil~/ Fuel Oil~.! Energy
Production Oil Cost Cost
Year (1000 kWh) (~allons) ($/~allon) ($)
1982
1983 464 51,600 1.82 93,900
1984 494 54,900 1.87 102,700
1985 31 3,400 1.92 6,500
1986 34 3,800 1.97 7,500
1987 36 4,000 2.02 8,100
1998 39 4,300 2.07 8,900
1989 41 4,600 2.12 9,800
1990 44 4,900 2.18 10,700
1991 49 5,400 2.23 12,000
1992 53 5,900 2.29 13,500
1993 58 6,400 2.35 15,000
1994 63 7,000 2.41 16,900
1995 68 7,600 2.48 18,800
1996 73 8,100 2.54 20,600
1997 78 8,700 2.61 22,700
1998 83 9,200 2.67 24,600
1999 87 9,700 2.74 26,600
2000 92 10,200 2.82 28,800
2001 100 11,100 2.89 32,100
2002-
2034 100 11,100 2.89 32,100
~/ Required supplemental diesel generation from Table VlI-10.
~ 111.1 gallons per megawatt-hour. Rounded to nearest 100
gallons.
3/
~/
Escalated at 2.6 percent annually.
Rounded to nearest $100.
NBI-411-9523-IX-12
• I I I I •
TABLE IX-12
RECOMMENDED HYDROELECTRIC PROJECT
DIESEL COSTS
LARSEN BAY
Fi rill .. !.! Schedule Of~/ Annual..!!/ ~ Operatio~/ Lubricatio~/ Fuel!....! Insurancei/~ and Annual
Capacity Investment Cost Maintenance Oil Oil Cost
Year (KW) ( $) ( $) ( $) ($) ($) ($) ($)
1982 300 550,000
1983 300 30,500 3,300 67,900 1,100 93,900 196,700
1984 300 30,500 3,300 68,400 1,200 102,700 206,100
1985 300 30,500 3,300 30,500 100 6,500 70,900
1986 300 30,500 3,300 30,600 100 7,500 72,000
1987 300 30,500 3,300 30,600 100 8,100 72,600
1988 300 30,500 3,300 30,700 100 8,900 73,500
1989 300 30,500 3,300 30,700 100 9,800 74,400
1990 300 30,500 3,300 30,700 100 10,700 75,300
1991 300 30,500 3,300 30,800 100 12,000 76,700
1992 300 30,500 3,300 30,900 200 13,500 78,400
1993 300 30,500 3,300 31,000 200 15,000 80,000
1994 300 30,500 6,300 31,100 200 16,900 82,000
1995 300 30,500 3,300 31,200 200 18,800 84,000
1996 300 30,500 3,300 31,200 200 20,600 85,800
1997 300 30,500 3,300 31,300 300 22,700 88,100
1998 300 30,500 3,300 31,400 300 24,600 90,100
1999 300 30,500 3,300 31,500 300 26,600 92,200
2000 300 30,500 3,300 31,600 300 28,800 94,500
2001 300 30,500 3,300 31,700 400 32,100 98,000
2002 300 30,500 3,300 31,700 400 32,100 98,000
2003 300 20,400 3,300 31,700 400 32,100 87,900
2004 300 20,400 3,300 31,700 400 32,100 87,900
2005 300 20,400 3,300 31,700 400 32,100 87,900
2006 300 20,400 3,300 31,700 400 32,100 87,900
2007 300 20,400 3,300 31,700 400 32,100 87,900
2008 300 20,400 3,300 31,700 400 32,100 87,900
2009 300 20,400 3,300 31,700 400 32,100 87,900
2010 300 20,400 3,300 31,700 400 32,100 87,900
2010 300 20,400 3,300 31,700 400 32,100 87,900
2011 300 400,000 20,400 3,300 31,700 400 32,100 87,900
2012-34 300 20,400 3,300 31,700 400 32,100 87,900
The largest unit is omitted when calculating firm capacity. 1/
2/
3/
4/
5/
6/
7/
8/
Build fuel storage facility in 1982 for $150,000. Replace plant every 30 years for $400,000.
Tank cost amortized over 20 years at 3 percent. Plant cost amortized over 30 years at 3 percent.
Plant replacement value is $400,000. Insurance cost is $0.83 per $100 replacement value.
From Table IX-9.
From Table IX-10.
From Table IX-II.
Nearest $100.
NBI-411-9523-IX-9
, . I • , I , . I • I , I • , . I I , I , I • • I I I • I • I •
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....
....
TABLE IX-13
RECOMMENDED HYDROELECTRIC PROJECT
HYDROELECTRIC COSTS
LARSEN BAY
Capi tal.!!
Operation~/ ii/ Replacementl/ Rep1acement2./ ii/
and Schedule of Sinking
Cost Amortizatioo1/ 2../ Maintenance Investment Fund
Year ($) ($) ($) ($) ($)
1982 0
1983 0
1984 2,821,400 0
1985 109,700 35,800 6,600
1986 109,700 35,800 6,600
1987 109,700 35,800 6,600
1988 109,700 35,800 6,600
1989 109,700 35,800 6,600
1990 109,700 35,800 6,600
1991 109,700 35,800 6,600
1992 109,700 35,800 6,600
1993 109,700 35,800 6,600
1994 109,700 35,800 6,600
1995 109,700 35,800 6,600
1996 109,700 35,800 6,600
1997 109,700 35,800 6,600
1998 109,700 35,800 6,600
1999 109,700 35,800 6,600
2000 109,700 35,800 6,600
2001 109,700 35,800 6,600
2002 109,700 35,800 6,600
2003 109,700 35,800 6,600
2004 109,700 35,800 6,600
2005 109,700 35,800 6,600
2006 109,700 35,800 6,600
2007 109,700 35,800 6,600
2008 109,700 35,800 6,600
2009 109,700 35,800 80,000 6,600
2010 109,700 35,800 6,600
2011 109,700 35,800 6,600
2012-34 109,700 35,800 208,980 6,600
1/
2/
3/
4/
11
!!..I
From Table VIII-I.
50 years at 3~.
1.5~ of contract cost.
Replace turbine runner in 2009; replace transmission lines in 2014.
Runner fund 25 years at 3~. Transmission Lines fund 30 years at 3~.
Funds are superimposed and in perpetuity.
Values rounded to nearest $100.
NBI-411-9523-IX-8
Annual
Cost
($)
0
0
0
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
152,100
• -
TABLE IX-14 •
SUMMARY -RECOMMENDED PROJECT DEVELOPMENT COSTS
LARSEN BAY -
AnnuaL!! Annual~/ -AnnuaI1!
Total
-----Ge~7ration Mix-----Hydro Diesel Annual
Demand Hydr= Dieseill Cost Cost Cost -Year (1000 kWh) (1000 kWh) (1000 kWh) ($) ($) ($) -1982
1983 464 0 464 0 196,700 196,700 ..
1984 494 0 494 0 206,100 206,100 ..
1985 525 494 31 152,100 70,900 223,000
1986 536 502 34 152,100 72,000 224,100 •
1987 547 511 36 152,100 72,600 224,700 ..
1988 558 519 39 152,100 73,500 225,600
1989 569 528 41 152,100 74,400 226,500 ..
1990 580 536 44 152,100 75,300 227,400 • 1991 593 544 49 152,100 76,700 228,800
1992 605 552 53 152,100 78,400 230,500 ..
1993 618 560 58 152,100 80,000 232,100 • 1994 631 568 63 152,100 82,000 234,100
1995 644 576 68 152,100 84,000 236,100 •
1996 656 583 73 152,100 85,800 237,900 ..
1997 669 591 78 152,100 88,100 240,200
1998 682 599 83 152,100 90,100 242,200 •
1999 694 607 87 152,100 92,200 244,300 -2000 707 615 92 152,100 94,500 246,600
2001 723 623 100 152,100 98,000 250,100 ..
2002 723 623 100 152,100 98,000 250,100 ..
2003 723 623 100 152,100 87,900 240,000
2004 723 623 100 152,100 87,900 240,000 ..
2005 723 623 100 152,100 87,900 240,000 -2006 723 623 100 152,100 87,900 240,000
2004 723 623 100 152,100 87,900 240,000 • 2008 723 623 100 152,100 87,900 240,000 ..
2009 723 623 100 152,100 87,900 240,000
2010 723 623 100 152,100 87,900 240,000 ..
2011 723 623 100 152,100 87,900 240,000 ..
2012-34 723 623 100 152,100 87,900 240,000 ..
•
• 1/ From Tables VII-9A through VII-9D. Intermediate values by interpolation. • 2/
3/ From Tables VII-9A through VII-9D. Intermediate values by interpolation.
4/ Difference between annual demand and demand met by hydro. .. From Table IX-13. ~/ From Table IX-12. ..
NBI-411-9523-IX-13 • •
• •
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iii_
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.. ""
TABLE IX-15
RECOMMENDED HYDROELECTRIC PROJECT
SPACE HEATING CREDIT
LARSEN BAY
Oil~/ Oi I Uni 0./ Schedule of~./ Net
Energy-!/
Annual
Equivalent Cost Creditil Investment Amortizato~/ Savings
Year (1000 kWh) (gal) ($/ gal) ($) ($) ($) ($)
1982 0 0 1.78 0
1983 0 0 1.82 0
1984 0 0 1.87 0 $40,000
1985 530 18,700 1.92 35,900 1,600 34,300
1986 526 18,600 1.97 36,600 1,600 35,000
1987 523 18,500 2.02 37,400 1,600 35,800
1988 519 18,300 2.07 37,900 1,600 36,300
1989 516 18,200 2.12 38,600 1,600 37,000
1990 512 18,100 2.18 39,500 1,600 37,900
1991 508 17,900 2.23 39,900 1,600 38,300
1992 504 17,800 2.29 40,800 1,600 39,200
1993 500 17,700 2.35 41,600 1,600 40,000
1994 496 17,500 2.41 42,200 1,600 40,600
1995 492 17,400 2.48 43,200 1,600 41,600
1996 487 17,200 2.54 43,700 1,600 42,100
1997 483 17 , 100 2.61 44,600 1,600 43,000
1998 479 16,900 2.67 45,100 1,600 43,500
1999 475 16,800 2.74 46,000 1,600 44,400
2000 471 16,600 2.82 46,800 1,600 45,200
2001-34 467 16,500 2.89 47,700 1,600 46,100
1/
2/
3/
4/
5/
6/
From Tables VII-9A through VII-9D.
138,000 BTU/gal, 3,413 BTU/kWh, 70%
gallons.
Escalated at 2.6% annually.
Rounded to nearest $100 .
See Appendix G for cost estimate.
50 years at 3%.
Intermediate values by interpolation.
efficiency. Rounded to nearest 100
-NBI-411-9523-IX_14
.. 1f
TABLE IX-16
RECOMMENDED HYDROELECTRIC PROJECT
SUMMARY
LARSEN BAY
Project..!..! Present Worth.~/ Space~/
Present Wort~/ Heating
Cost Project Cost Credit Heating Credit
Year ($) ($) ($) ($)
1982 0 0 0 0
1983 196,700 185,400 0 0
1984 206,100 186,600 0 0
1985 223,000 198,100 34,300 30,500
1986 224,100 193,300 35,000 30,200
1987 224,700 188,200 35,800 30,000
1988 225,600 183,400 36,300 29,600
1989 226,500 178,800 37,000 29,200
1990 227,400 174,300 37,900 29,000
1991 228,800 170,300 38,300 28,500
1992 230,500 166,500 39,200 28,300
1993 232,100 162,800 40,000 28,100
1994 234,100 159,400 40,600 27,600
1995 236,100 156,100 41,600 27,500
1996 237,900 152,700 42,100 27,000
1997 240,200 149,700 43,000 26,800
1998 242,200 146,500 43,500 26,300
1999 244,300 143,500 44,400 26,100
2000 246,600 140,600 45,200 25,800
2001 250,100 138,500 46,100 25,500
2002 250,100 134,400 46,100 24,800
2003-34 240,000 2,630,600 46,100 505,300
TOTALS 5,941,700 1,006,100
From Table IX-14. 1/
2/ Discounted to January 1982 at 3% interest. Present worth
factors accurate to four decimal places. Values rounded to
nearest $100.
3/ From Table IX-15.
NBI-411-9523-IX-15
• ---
• ---.
•
•
• •
• •
• •
• ..
• ..
•
lit
•
•
• •
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B.
1J
2/
11
TABLE IX-17
PRESENT WORTH SUMMARY
LARSEN BAY
BASE CASE (Benefits)
Gross Present Worth Costs .l!
Waste Heat Recovery Credit .l!
Subtotal
Wind Credit Y
Subtotal
Space Heating Credit 11
Total
RECOMMENDED HYDROELECTRIC PROJECT (Costs)
Gross Present Worth Costs 11
From Table IX-8.
From Table IX-6A .
From Table IX-16.
NBI-411-9523-IX-18
7,532,100
807,000
6,725,100
382,600
6,342,500
1,006,100
7,348,600
5,941,700
A. BASE CASE
B. BASE CASE
ONLY
B/C =
TABLE IX-18
BENEFIT/COST RATIOS
LARSEN BAY
7,532,100
5,941,700 = 1.268
INCLUDING WASTE HEAT RECOVERY
B/C = 6,725,100 _ 1.132 5,941,700 -
CREDIT
• ..
•
• ----
•
•
• •
• ..
• •
C. BASE CASE INCLUDING WASTE HEAT RECOVERY CREDIT AND WIND •
CREDIT ..
•
B/C = 6,342,500 = 5,941,700 1.067 •
•
D. BASE CASE INCLUDING WASTE HEAT RECOVERY CREDIT, WIND ..
CREDIT, AND SPACE HEATING CREDIT.
B/C 7,348,600 = = 5,941,700 1. 237
NBI-411-9523-IX-19
• •
• ..
• •
• ..
• • ..
/ .. .. ..
• •
i
Energy
Year Production 1 /
(1000 kWh) -
1982
1983 464
1984 494
1985 525
1986 536
1987 547
1988 558
1989 569
1990 580
1991 593
1992 605
1993 618
1994 631
1995 644
1996 656
1997 669
1998 682
1999 694
2000 707
2001-34 723
1.1 From Table VII-IO.
y From Table IX-8.
r ,
Base Case
Annual Cos~
($)
204,800
214,200
224,000
229,600
235,500
241,200
247,200
253,900
260,800
268,000
275,700
283,500
292,200
300,500
309,500
313,400
322,600
333,100
343,100
Unit En§~gy
Cos~
(Mills/kWh)
441
434
427
428
431
432
434
438
440
443
446
449
454
458
463
460
465
471
462
.Y Base case without waste heat recovery credit.
jj From Table IX-8.
~ Base case including waste heat recovery.
2.! From Table IX-6A.
1.1 Base case including waste heat recovery credit
SFNBI-426-9523-IX-20
• • t.
TABLE IX-19
ANNUAL UNIT COSTS
BASE CASE
LARSEN BAY
Waste
Heat Annu~}
Credi0.J Cos~
($) ($)
14,400 190,400
15,500 198,700
16,500 207,500
17,600 212,000
18,700 216,800
19,800 221,400
20,900 226,300
22,200 231,700
23,600 237,200
25,000 243,000
26,400 249,300
27,800 255,700
29,600 262,600
31,000 269,500
32,900 276,600
34,500 278,900
36,200 286,400
38,300 294,800
40,400 293,700
Unit
Ener~y
Cos~
(Mills/kWh)
410
402
395
396
396
397
398
399
400
402
403
405
408
411
413
409
413
417
406
and wind generation credit.
~ . .
Wind
Generat~?n
Credi~
AnnuH
Cos~
Enern
Cos~
($) ($) (Mills/kWh)
4,900 185,500 400
5,400 193,300 391
5,900 201,600 384
6,300 205,700 384
6,800 210,000 384
7,300 214,100 384
7,700 218,600 384
8,300 223,400 385
11,700 225,500 380
12,400 230,600 381
13,200 236,100 382
14 ,000 241,700 383
14,900 247,700 385
15,600 253,900 387
16,500 260,100 389
17,200 261,700 384
18,100 268,300 387
19,100 275,700 390
19,900 273,800 379
• -
•
TABLE IX-20 •
ANNUAL UNIT COSTS •
RECOMMENDED HYDROELECTRIC PROJECT -
LARSEN BAY •
Hydro •
Project Unit Space Unit •
Energy Annual Energy Heating Annual Energy
Year Productionl! Cost Cost Credit Cost Cost ...
(1000 kWh) ( $) (Mills/kWh) . ( $) ( $) (Mills/kWh) • 1982 ..
1983 464 196,100 423 0 196,100 423
1984 494 206,100 417 0 206,100 417 • 1985 525 223,000 425 34,300 188,700 359 • 1986 536 224,100 418 35,000 189,100 353
1987 547 224,700 411 35,800 188,900 345 ..
1988 558 225,600 404 36,300 189,300 339 ..
1989 569 226,500 398 37,000 189,500 333
1990 580 227,400 392 37,900 189,500 327 • 1991 593 228,800 386 38,300 190,500 321 .,
1992 605 230,500 381 39,200 191,300 316
1993 618 232,100 376 40,000 192,100 311 • 1994 631 234,100 371 40,600 193,500 307
1995 644 236,100 367 41,600 194,500 302 •
1996 656 237,900 363 42,100 195,800 298 • 1997 669 240,200 359 43,000 197,200 295
1998 682 242,200 355 43,500 198,700 291 •
1999 694 244,300 352 44,400 199,900 288 • 2000 707 246,600 349 45,200 201,400 285
2001 723 250,100 346 46,100 204,000 282
.,
2002 723 250,100 346 46,100 204,000 282 • 2003-34 723 240,000 332 46,100 193,900 268 ..
• -
•
•
• ...
•
.Y From Table VII-10. ...
2/ From Table IX-14. • ..
SFNBI-426-9523-IX-21 • ...
....
....
.....
.....
....
....
....
....
Year
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002-34
TABLE IX-1A
BASE CASE
WIND ENERGY CREDIT
DIESEL OPERATION AND MAINTENANCE COSTS
LARSEN BAY
Annual
Energy..!!
Production
(1000 kWh)
84
84
84
84
84
84
84
84
112
112
112
112
112
112
112
112
112
112
112
112
Maintenance.Y
($)
1,400
1,400
1,400
1,400
1,400
1,400
1,400
1,400
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
Operation1!
($)
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
~/ From Table VII-12.
Annual
Cost
($)
1,400
1,400
1,400
1,400
1,400
1,400
1,400
1,400
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
1,900
~/ $17 per megawatt-hour. Values rounded to nearest $100.
~ Salary for operator, included in base case costs.
SFNBI-411-9523-IX-1A
TABLE IX-2A
BASE CASE
WIND ENERGY CREDIT
DIESEL LUBRICATION OIL COSTS
LARSEN BAY
Annual.lJ Lubrication~./ Lu br ica t iord! Energy
Production Oil Oil Cost
Year (1000 kWh) (gallons) ($!~allon)
1982
1983 84 50 4.05
1984 84 50 4.16
1985 84 50 4.27
1986 84 50 4.38
1987 84 50 4.49
1988 84 50 4.61
1989 84 50 4.73
1990 84 50 4.85
1991 112 67 4.98
1992 112 67 5.11
1993 112 67 5.24
1994 112 67 5.37
1995 112 67 5.51
1996 112 67 5.66
1997 112 67 5.81
1998 112 67 5.96
1999 112 67 6.11
2000 112 67 6.27
2001 112 67 6.43
2002-34 112 67 6.43
~! From Table VII-12.
~! 0.6 gallons per megawatt-hour.
1! Escalated at 2.6 percent annually.
±! Values rounded to nearest $100.
SFNBI-411-9523-IX-2A
Lubricationi.l
Oil Cost
($)
200
200
200
200
200
200
200
200
300
300
400
400
400
400
400
400
400
400
400
400
• .. -.. ---..
• -
• ..
• • .. ..
• ..
•
•
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• .. ..
• ..
• •
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TABLE IX-3A
BASE CASE
DIESEL FUEL OIL COSTS
WIND ENERGY CREDIT
LARSEN BAY
Annuall./
Energy Equivalen~ Fuel Fuel
Production Oil Oil Cost Oil Cost
Year (1000 kWh) (gallons) ($/gallon) ($)
1982
1983 84 9,300 1.82 16,900
1984 84 9,300 1.87 17,400
1985 84 9,300 1.92 17,900
1986 84 9,300 1.97 18,300
1987 84 9,300 2.02 18,800
1988 84 9,300 2.07 19,300
1989 84 9,300 2.12 19,700
1990 84 9,300 2.18 20,300
1991 112 12,400 2.23 27,700
1992 112 12,400 2.29 28,400
1993 112 12,400 2.35 29,100
1994 112 12,400 2.41 29,900
1995 112 12,400 2.48 30,800
1996 112 12,400 2.54 31,500
1997 112 12,400 2.61 32,400
1998 112 12,400 2.67 33,100
1999 112 12,400 2.74 34,000
2000 112 12,400 2.82 35,000
2001 112 12,400 2.89 35,800
2002-34 112 12,400 2.89 35,800
1/
2/
From Table VII-12.
111.1 gallons per megawatt-hour. Based on 138,000
Btu/gallon, 3,413 Btu/kWh, and 22 percent efficiency.
Values rounded to nearest 100 gallons.
SFNBI-411-9523-IX-3A
•
•
• -TABLE IX-4A • BASE CASE -WIND ENERGY GENERATION CREDIT
LARSEN BAY
SUMMARY • •
InstalledlJ Operation~/ Lubr ica t iord/ FueLi./ Total •
Year Capacity Maintenance Oil Oil Credit -(kW) ($) ($) ($) ($)
• 1982
1983 30 1,400 200 16,900 18,500 •
1984 30 1,400 200 17,400
1985 30 1,400 200 17,900
19,000 • 19,500
1986 30 1,400 200 18,300 19,900 •
1987 30 1,400 200 18,800
1988 30 1,400 200 19,300
20,400 • 20,900
1989 30 1,400 200 19,700 21,300 •
1990 30 1,400 200 20,300
1991 40 1,900 300 27,700
21,900 • 29,900
1992 40 1,900 300 28,400 30,600 ..
1993 40 1,900 400 29,100
1994 40 1,900 400 29,900
31,400 • 32,200
1995 40 1,900 400 30,800 33,100 •
1996 40 1,900 400 31,500 33,800
1997 40 1,900 400 32,400 34,700 •
1998 40 1,900 400 33,100 35,400 •
1999 40 1,900 400 34,000 36,300
2000 40 1,900 400 35,000 37,300 •
2001 40 1,900 400 35,800 38,100 •
2002 40 1,900 400 35,800 38,100
2034 40 1,900 400 35,800 38,100 • -
• •
•
iii ..
• 1/ From Table VII-12.
~/ From Table IX-1A.
3/ From Table IX-2A.
It
•
4/ From Table IX-3A. •
SFNBI-411-9523-IX_4A •
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Year
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2005
2034
1/
2/
3/
4/
TABLE IX-5A
BASE CASE
WIND GENERATION COSTS
LARSEN BAY
InstallectlJ Schedule o~
Amort iza tion .. ~/ Operator Annual
Capacity Investmen~/ Maintenance~/ Cost
(kW) ($) ($) ($) ($)
102,000
30 8,500 5,100 13,600
30 8,500 5,100 13,600
30 8,500 5,100 13,600
30 8,500 5,100 13,600
30 8,500 5,100 13,600
30 8,500 5,100 13,600
30 8,500 5,100 13,600
30 34,000 8,500 5,100 13,600
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 102,000 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 11,400 6,800 18,200
40 34,000 11,400 6,800 18,200
40 11,400 6,800 18,200
From Table VII-12.
Replace equipment every 15 years. Build first plant in 1982 and
bring on line in 1983. Expand capacity in 1990. Table 111-12.
15 years at 3% in perpetuity rounded to the nearest $100.
5% of capital cost rounded to the nearest $100.
SFNBI-411-9523-IX-5A
• -
•
• TABLE IX-6A
• BASE CASE .. WIND ENERGY CREDIT
LARSEN BAY • PRESENT WORTH •
InstallecJ} Annual~ Annual~/ Net Annual Presenti./ • Year Capacity Credit Cost Credit Worth • (kW) ($) ($) ($) ($)
• 1982
1983 30 18,500 13,600 4,900 4,600 ..
1984 30 19,000 13,600 5,400 4,900 .. 1985 30 19,500 13,600 5,900 5,200
1986 30 19,900 13,600 6,300 5,400 ..
1987 30 20,400 13,600 6,800 5,700
1988 30 20,900 13,600 7,300 5,900 ..
1989 30 21,300 13,600 7,700 6,100 ..
1990 30 21,900 13,600 8,300 6,400
1991 40 29,900 18,200 11,700 8,700 •
1992 40 30,600 18,200 12,400 9,000 ..
1993 40 31,400 18,200 13,200 9,300
1994 40 32,200 18,200 14,000 9,500 •
1995 40 33,100 18,200 14,900 9,900 ..
1996 40 33,800 18,200 15,600 10,000
1997 40 34,700 18,200 16,500 10,300 •
1998 40 35,400 18,200 17,200 10,400 ..
1999 40 36,300 18,200 18,100 10,600
2000 40 37,300 18,200 19,100 10,900 •
2001 $239,800 •
2034 40 38,100 18,200 -TOTAL $382,600 -
• ..
• ..
• •
1/ From Table VII-12. .. 2/ From Table IX-4A. 3/ From Table IX-5A. • 4/ Discounted at 3% to January 1982. Present worth factors
accurate to 4 decimal places. • •
SFNBI-411-9523-IX-6A • •
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....
SECTION X
ENVIRONMENTAL AND SOCIAL EFFECTS
A. GENERAL
An environmental study of the Larsen Bay Hydroelectric
Project vicinity was conducted to survey the resources in the
area, evaluate potential effects of the project, and formulate
measures to avoid or ameliorate adverse effects. Two field
investigations were made, relevant literature was reviewed, and
representatives of the Alaska Departments of Natural Resources
and of Fish and Game, the U.S. Fish and Wildlife Service, and
the Kodiak National Wildlife Refuge were consul ted. Local
residents were contacted through a community meeting and
through discussions with individuals.
The Larsen Bay Hydroelectric Project will offer a signifi-
cant advantage to the local community--a central power
source. It will also bring modest socioeconomic benefits.
While some potential for adverse environmental and social
effects exists, adequate project planning should be able to
avoid these consequences •
The study results indicate that most of the adverse
environmental effects of the project will be minor due to the
limited scope of the project activities, the inability of
salmon to spawn above the old diversion dam on Humpy Creek, the
abundance of alternative areas available for trapping, hunting,
and general recreation, and the availability of measures to
mitigate potential effects from the construction and operation
of the facilities .
The project access road could lead to the serious
disturbance of wildlife if it opened the higher ridge country
NBI-388-9523-X X-l
to recreational vehicles; however, project plans call for this
road to end at a point where further travel by vehicle would
require road-blasting activities and the removal of large
trees.
If implemented, the project will make a centralized power
source available to a community that now depends on individual
generators. That community, however, will have to be protected
against possible disturbances that could be introduced by
importing a project construction work force into what is
essentially a small, isolated village. Establishment of a
trailer work camp is recommended to accommodate the workers.
The areas considered in the study included fisheries, wild-
life, vegetation, archaeological and historic sites, visual
resources, recreation, air quality, and socioeconomic
impacts. Land status, hydrology, and geology are addressed in
Section IV, Basic Data. The detailed report on the environmen-
tal studies conducted is contained in Appendix E and a summary
of the study is presented in this section.
B. ENVIRONMENTAL EFFECTS
1. Fisheries
The Alaska Fisheries Atlas published by the Alaska Depart-
ment of Fish and Game (ADF&G) lists pink salmon and Dolly
Varden char as the only fish species present in Humpy Creek.
Local residents confirmed this in general, but they added that
some rainbow trout are present as well.
Fish surveys were taken only twice on Humpy Creek in recent
years. In 1977, 12,075 pinks were counted in a foot survey,
and in 1981 600 pinks were counted in an aerial survey.
NBI-388-9523-X X-2
• -
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In Humpy Creek most of the spawning occurs intertidally and
wi thin the firs t 100 yards above the cuI vert of the exist ing
road. Only in years with large runs, do a few pink salmon get
upstream as far as the old diversion dam. This dam, builtin
1923, has a 1 O-f oot fall, and it prevents f ish passage. Thus
the proposed facili ties will not affect the salmon spawning.
Some Dolly Varden, however, do exist above the old dam.
Fish from the sea traditionally have formed a large portion
of the diet of Larsen Bay residents. Subsistence harvesting of
the Humpy Creek pink salmon run is still common but no figures
are available on the total catch.
The portion of Humpy Creek between the diversion weir and
the powerhouse may be dewatered during low flows, and a major
reduction in flow will occur during plant operations. These
project-related effects may prevent fish from utilizing this
st ream sect ion. However, on ly small numbers of Dolly Varden
char were found in this section of the stream. No significant
effect on water quanti ty or quali ty is anticipated downstream
from the powerhouse outflow.
Construction activity will cause minor increases in erosion
and sedimentation during the short period of construction.
These impacts can be minimized through the use of proper con-
struction practices. Also, the design of the diversion weir
will allow it to be collapsed temporarily should it prove
necessary to flush sediment out of spawning gravels below the
weir .
2. Wildlife
Wildlife existing in the project area were identified by
consul ting existing Ii terature and by contacts with personnel
of ADF&G, the Kodiak National Wildlife Refuge, the U.S. Fish
and Wildlife Service, and local residents . Bear, otter, fox,
NBI-388-9523-X X-3
and weasel all commonly use the Humpy Creek drainage. Brown
bear are constant visi tors in Larsen Bay during the summer,
fishing tbe lower reacbes of the creek for salmon and visiting
tbe creek and village dump. About 10 to 15 bears frequent the
hydro project si teo Denning probably occurs on the mountain
being considered for the diversion weir, but the facility is
below tbe 400-foot level and most dens are probably above 700
feet.
Si tka black-tailed deer are abundant in tbe Larsen Bay
area. The Humpy Creek drainage supports deer all year but is
probably not a major wintering area.
Eigbt bald eagle nests have been recorded in the Larsen bay
drainage.
although
No nests have been identified along Humpy Creek
eagles do feed at the mouth of the creek. Rough-
legged bawks probably nest in the upper project area. Lists of
mammals and birds found on Kodiak Island Archipelago are
presented in Appendix E.
Most of the local hunting efforts do not occur near the
proposed projec t site. Local bunters general 1 y hunt across
Larsen Bay and Uyak Bay. Most of tbe red fox and land otter
trapping and hunting occurs away from the project area, but
local residents occasionally trap in or near the area.
No endangered species occur on Kodiak Island, according to
the U.S. Fish and Wildlife Service, although the Peales
peregrine falcon, the nonendangered subspecies, does nest on
tbe island.
Project construction will result in permanent habitat loss
in the diversion weir site, the powerhouse location, and the
access route to the dam si teo Due to the small size of the
project, this loss is expected to be minimal. Temporary habi-
tat disturbance will occur at equipment staging areas and in
NBI-388-9523-X
• -
•
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•
•
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-
the transmission
anticipated from
line right-of-way. Few adverse effects are
gravel removal for project construction
because an existing borrow site will be used.
Operation of heavy equipment and other construction acti-
vities will create considerable noise that will disturb wild-
life and cause some species to abandon traditionally used
areas. However, all construction activity should occur within
a six-month period or less. Also the proximi ty of the town
acts to limit wildlife numbers in the project area.
During project operation, alterations in the flow regime
between the diversion weir and the powerhouse may force water-
dependent animals such as the water ouzel to relocate.
A major potential impact from construction of a hydropower
facility would occur if the route to the diversion dam allowed
vehicle access above the alder zone. The use of three-wheeled
vehicles and snow machines is a popular sport in Larsen Bay.
Once above the alder zone, these recreational vechicles could
probably be taken the entire length of the ridge between Karluk
Lake and Uyak Bay. This area is good deer habi tat and an
important denning area for brown bear. Wildlife officials fear
that the use of recreational vehicles on this ridge could
crea te serious disturbances to wi ld life. To discourage th is
potential abuse, project plans call for the road to terminate
in a very narrow portion of Humpy Creek drainage where exten-
sion of the road would require blasting and tree removal .
For the most part, the proposed project is on such a small
scale that construction impacts will be minor and short term.
The use of prudent construction practices can further minimize
impacts. The transmission line to the town of Larsen Bay will
follow the alignment of the existing road, so habi tat losses
will be limited • A construction buffer zone should be estab-
lished around any active eagle nests in the project area .
NBI-388-9523-X X-5
•
•
3. Vegetation • -
Birch is the dominant tree throughout most of the Humpy -
Creek drainage except in outwash plains where it is replaced by
cot tonwood. The understory varles with the density of canopy
cover, with the following species predominant: elderberry,
highbush cranberry, rose, lady and fiddlehead fern, and
scattered alder and willow.
4. Archaeologic and Historic Sites
An archaeological site has been located at the mouth of
Humpy Creek, but the extent of the site is unknown. The
Division of Parks has recommended that an archaeological survey
be done in this area before construction begins and the U. S.
Fish and Wildlife Service also requires an on-site survey.
Archaeological artifacts are common throughout the Larsen Bay
area. Workers associated with the project must be caut ioned
about the unauthorized removal of artifacts.
5. Visual Resources
The transmission line is the only project feature that may
be visible from town.
6. Recreation
Project construction and operation should have little
impact on recreational values since little or no fishing occurs
above the old dam and other areas for trapping, hunting, and
picnicking exist in abundance. The route to the diversion weir
may open up additional areas for the use of three-wheeled
vehicles. This possible use should be prohibited due to the
potential disturbance to wildlife in the upper ridge country.
NBI-388-9523-X X-6
-
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7. Air Quality
During project construction, exhaust fumes from diesel
equipment and dust generated by construction activity may
diminish air quality. Winds are common in this area, however,
and they should rapidly disperse air pollutants.
Electrical power for Larsen Bay is currently provided with
diesel generators. To the extent that hydro power replaces the
diesel generating facilities, the discharge of hydrocarbon
pollutants should be lowered.
C. SOCIOECONOMIC EFFECTS
The economic analysis for the Larsen Bay Hydroelectric
Project assumed that a central distribution system, which does
not now exist, was already in place. Thus, the distribution
system must be installed before the project can produce any
benef i ts. I f implemented, however, the project wi 11 br ing a
significant socioeconomic benefit to the local community--a
central power source--and it will offer modest benefits from
project-related payrolls and employment. The potential exists
for social disturbances, but adequate project planning can
avoid these possible sources of friction.
The project will expand the payroll in the local area
during construction and it should provide some local jobs if
workers with suitable skills can be found. In fact, the Kodiak
Area Native Association has expressed a willingness to provide
training to local residents so that they will be qualified to
work on this project. It will be important to use as many
local residents as possible because employment opportuni ties
are 1 imi ted in the area. Otherwise, the local resi den ts may
resent the importation of workers to construct , operate, and
maintain the project facilities. The project construction
force, though, is not expected to exceed 21 and it will average
NBI-388-9523-X X-7
about 16. If accommodations for the imported construction
workers are not available, which is likely, trailers can be
brought in to set up a temporary work camp.
The manager of the project construction team should take
precautions to ensure that the imported workers cause as little
disruption of the traditional life style of Larsen Bay as
possible. This is a small, isolated community and the tempo-
rary intrusion of the project work force must be handled with
consideration for the needs and wishes of the local popula-
tion. The use of a trailer camp to accommodate the imported
work force would simplify this task. The intensive work
schedule will also limi t the time available to the imported
work force for recreation.
NBI-388-9523-X X-8
• -
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SECTION XI
PROJECT IMPLEMENTATION
A. GENERAL
This chapter presents comments regarding the various
licenses, permits, and inst i tutional considerations that will
be encountered during the implementation phase of the Larsen
Bay project. A project development schedule is also presented
and discussed.
B. PROJECT LICENSES, PERMITS, AND INSTITUTIONAL CONSIDERATIONS
The following permits may be required for construction of
the Humpy Creek facility:
1. Under the authority of Sect ion 404 of the Federal
Water Pollution Control Act Amendments of 1972, the
Army Corps of Engineers (COE) must authorize the
discharge of dredged or fill materials into navigable
waters, which includes adjacent wetlands, by all
individuals, organizations, commercial enterprises,
and federal, state and local agencies. A COE Section
404 Permit will therefore be required for the
diversion weir on Delta Creek •
2. A Water Quality Certificate from the State of Alaska,
Department of Environmental Conservation (DEC), is
also required for any acti vi ty that may resul t in a
discharge into the navigable waters of Alaska.
Application for the certificate is made by submitting
to DEC a letter requesting the certificate, accom-
panied by a copy of the permit application being
submitted to the Corps of Engineers •
NBI-411-9523-XI XI-l
3.
4.
The Alaska Department of Fish and Game, Habitat Divi-
sion, under authority of AS 16.05.870, the Anadromous
Fish Act, requires a Habitat Protection Permit if a
person or governmental agency desires to construct a
hydraulic project or affect the natural flow or bed of
a specified anadromous river, lake, or stream, or use
equipment in such waters. A Habitat Protection Permit
will be required for the diversion weir, and for any
bridging, instream or stream bank work on Delta Creek.
Under authority of AS 16.05.840, the Alaska Department
of Fish and Game can require, if the Commissioner
feels it necessary, that every dam or other obstruc-
tion built by any person across a stream frequented by
salmon or other fish be provided with a durable and
efficient fishway and a device for a efficient passage
of fish. A Habi tat Protect ion Permi t, wi 11 therefore
be required.
5. All publ ic or pri va te entities (except Federal agen-
cies) proposing to construct or operate a hydroelec-
tric power project must have a license from the
Federal Energy Regulatory Commission (FERC) if the
proposed site is located on a navigable stream, or on
U.S. lands, or if the project affects a U.S. govern-
ment dam or interstate commerce. For the Larsen Bay
project, a minor license may be required. The ques-
tion of whether or not this project is jurisdictional
under the FERC regulations is currently being studied.
6. A Permit to Construct or Modify a Dam is required from
the Forest, Land and Water Management Division of the
Alaska Department of Natural Resources for the con-
struct ion, enlargement, al tera t ion or repair of any
dam in the State of Alaska that is ten feet or more in
NBI-411-9523-XI XI-2
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7 .
height or stores 50 acre-feet or more of water. Since
the weir is less than ten feet high and has only mini-
mal storage, this permit is not likely to be required.
A Water Rights Permit is required from the Director of
the Division of Forest, Land and Water Management,
Alaska Department of Natural Resources, for any person
who desires to appropriate waters of the State of
Alaska. However, this does not secure rights to the
water. When the permit holder has commenced to use
the appropriated water, he should notify the director,
who will issue a Certificate of Appropriation that
secures the holder's rights to the water.
8. The proposed project area is located within the
coastal zone. Under the Alaska Coastal Management Act
of 1977, a determination of consistency with Alaska
Coastal Management Standards must be obtained from the
Di vision of Policy Development and Planning in the
office of the governor. Th is determination woul d be
made during the COE 404 Permit review.
9. Any party wishing to use land or facilities of any
National Wildlife Refuge for purposes other than those
designated by the manager-i n-charge and publ ished in
the Federal Register must obtain a Special Use Permit
from the U.S. Fish and Wildlife Service. This permit
may authorize such activities as rights-of-way; ease-
ments for pipelines, roads, utilities, structures, and
research projects; and entry for geologic reconnais-
sance or similar projects, filming and so forth.
Note that all lands that were part of a National Wild-
life Refuge before the passage of the Alaska Native
Claims Settlement Act and have since been selected and
conveyed to a Native corporation will remain under the
rules and regulations of the refuge.
NBI-411-9523-XI XI-3
C. PROJECT DEVELOPMENT SCHEDULE
• ..
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A proposed project development schedule starting at the _
time the initial draft is submitted is
XI-l.
presented in Figure
The schedule is based on the assumption that two separate
contracts would be awarded for the project construction. The
first would be for fabrication and delivery of the turbine-
generator equipment to the Port of Seattle and later
installation and the second would be for civil work
construction and installation in cooperation with the
manufacturer of the turbine-generator equipment.
The controlling activities on the proposed schedule are the
turbine-generator procurement and the construction period.
1. Turbine-Generator Procurement
According to manufacturers' estimates, approximately
one year
fabrication
is
(and
necessary
delivery
for turbine-generator
to the Port of Seat t Ie)
starting from the time of contract award. In addi-
tion, prior to the award a two-month period must be
allowed for advertising, bid preparation, and bid
evaluation. This in turn would be preceded by a
three-month period to prepare specifications.
2. Construction Period
The field construction period would require two to
three summer months of on-site activities, preceded by
one to two months of shipping and mobilization time.
Other critical tasks such as preparation of the civil plans
and specifications, award of the civil contract, procurement of
NBI-411-9523-XI XI-4
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the necessary permits and license, and coordination of project-
related activities with other affected agencies would be
accomplished during the turbine-generator procurement phase;
thus they are not directly controlling activities.
As shown, the project construction would be completed about
October 1, 1984. Following three months of commissioning and
debugging time, the project would come on-line about January 1,
1985 •
NBI-411-9523-XI XI-5
• i • "
Activity
1. State of Alaska DecisioD
..
"'
2. Secure Necessary Permits, Licenses
3. Turbine/Generator Contract
a. Prepare Turbine/Generator Spec.
b. Advertise k Evaluate Bids
c. Fabricate Turbine/Generator
d. Deliver Turbine/Generator to Seattle
4. Civil Contract
a. Prepare Civil Plans k Specs.
b. Advertise k Evaluate Bids
5. Construction Activities
a. Yobilization Period
b. Barge Shipment
c. Site Yobllization
d. Site Construction
6. Power Plant Co~nissionlng,
Debugging Period
7. Plant On-Line
NHI-410-9521-PDS
• ,
FIGURE XI-l
PROJECT DEVELOPYENT SCHEDULE
1982
J F Y A Y J J A S o N D J F Y
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1983 1984
A Y J J A S o N D J F Y A Y J J A S o N D
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SECTION XII
CONCLUSIONS AND RECOMMENDATIONS
A. CONCLUSIONS
On the basis of the studies completed for this report, the
following conclusions can be drawn:
1. The energy demands of Larsen Bay are sufficient to
utilize the energy
hydroelectric project.
produced by the proposed
2. The Larsen Bay Hydroelectric Project at the recommended
capacity of 270 kW is a feasible project.
3. The proposed project is a more economic means of
meeting the future electric needs of Larsen Bay than
the base case, or diesel, alternative.
4. The environmental effects from the construction and
operation of the proposed project are minor and will
have no major temporary or long-term impacts. The
project will, however, offer a significant advantage to
the community--a central power source.
B. RECOMMENDATION
In view
recommended
of
by
the conclusions
the consultant that
enumerated
actions
above, it
be ini t ia ted
is
to
implement the project.
along the general lines
Implementation.
NBI-426-9522-XII
Implementation can be
indicated in Section
accomplished
XI, Project
·i.fIt"
~,,,
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'1I'ilo"'(
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BIBLIOGRAPHY
LARSEN BAY
Alaska Department of Fish & Game. Alaska's Fisheries Atlas,
Volumes I and II, 1978.
Alaska Department of Fish & Game. Alaska's Wildlife and
Habitat, Volumes I and II, 1973.
CH2M HILL. Reconnaissance Study of Energy Requirements
& Alternatives for Akhiok-King Cove-Larsen Bay-Old
Harbor-Ouzinkie-Sand Point. For Alaska Power Authority, June
1981.
Department of Commerce. ESSA -Environmental Data Service,
Climatological Data Summary, Alaska.
Ebasco Services, Inc., Regional Inventory and Reconnais-
sance Study for Small Hydropower Projects: Aleutian Islands,
Alaska Peninsula, Kodiak Island, Alaska. Vols. 1 and 2,
October 1980.
Ott Water Engineers. Water Resources Atlas for USDA Forest
Service Region X, Juneau, Alaska. April 1979.
P~w~, T.L. Quatenary Geology of Alaska: U.S. Geological Survey
Professional Paper 835, 1975.
Robert W. Retherford Associates. "Preliminary Feasibility
Designs and Cost Estimates for a Hydroelectric Project Near
Larsen Bay, Alaska." January 1980.
U.S. Department of Energy, Alaska Power Administration.
"Hydroelectric Power Potential for Larsen Bay and Old Harbor,
Kodiak Island, Alaska." May 1978.
NBI-419-9523-B
u.s. Geological Survey. "Flood Characteristics of Alaskan
Streams," Water Resources Investigation 78-129, R. D. Lamke.
1979.
u.S. Geological Survey. "The Hydraulic Geometry of Some
Alaskan Streams South of the Yukon River (Open File Report), II
William E. Emmett, July 1972.
u.S. Geological Survey. "Water-Resources Data for Alaska Water
Year 1963 through Water Year 1980-1981."
u.S. Geological Survey. "Water Resources of Alaska (Open File
Report)"; A. J. Feulner, J. M. Childers, V. W. Norman; 1971.
u.S. Geological Survey. "Water Resources of the Kodiak-
Shilikof Subregion, South-Central Alaska," Atlas HA-612,
Jones, et al., 1978.
Woodward-Clyde Consultants. Valdez Flood Investigation
Technical Report. February 1981.
NBI-419-9523-B
S. H.
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LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX A
PROJECT DRAWINGS
filii'
PLATE I
PLATE II
PLATE III
PLATE IV
PLATE V
PLATE VI
I".
TABLE OF CONTENTS
GENERAL PLAN
INLET STRUCTURE AND ONE-LINE DIAGRAM
PENSTOCK AND ACCESS ROAD--PLAN, PROFILE AND
SECTIONS
DIVERSION FACILITIES--PLAN, ELEVATION AND
SECTIONS
POWERHOUSE--PLANS AND SECTIONS
TYPICAL CROSSARM CONSTRUCTION ASSEMBLY
......
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LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX B
HYDROLOGY
'.
TABLE OF CONTENTS
,...
PAGE
iIIIif A. GENERAL 1
-J B. AREA DESCRIPTION 1
.. C . DATA UTILIZED 4
D. PROJECT STREAM FLOWS 5 ..
E . DIVERSION WEIR FLOOD FREQUENCY 11
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F. CONSIDERATION OF POTENTIAL RIVER ICE
PROBLEMS 14
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NBI-426-9523-TC -
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A. GENERAL
The following report provides the estimates, the method-
ology, and the background data on stream flows near the village
of Larsen Bay, located on Kodiak Island in south-central
Alaska. Also included is a generalized wri teup of potential
ice problems in the vicinity of Larsen Bay and elsewhere.
Since the streamflows dictate the amount of energy that can be
produced by a particular dam and power plant configuration,
their accuracy critically affects the feasibility of the proj-
ect. Better than average estimates can now be made for the
proposed Humpy Creek si te because more than a year of flow
records is now available from a stream gage installed by the
U.S. Geological Survey in anticipation of this project. These
measurements should be continued for some addi tional time to
assess the variability of flow. In the meantime, information
from other areas of Kodiak Island bas been used to place this
single year of record in context wi th the expected long-term
flows.
This report describes the general characteristics of the
Larsen Bay region and the basin that feeds Humpy Creek. The
data used in the hydrologic analysis and streamflow and flood
frequency data from Humpy Creek are also presented. A list of
the references ci ted in the text is presented at the end of
this report .
B. AREA DESCRIPTION
1. Regional Setting
The village of Larsen Bay is located near the junction of
two fjords, Larsen Bay and Uyak Bay, on the northwest coast of
Kodiak Island. Shelikof Strait, separating Kodiak Island from
the mainland, lies 14 miles to the northwest. The city of
Kodiak lies 60 miles east and the village of Old Harbor, the
NBI-388-9523-B* 1
site of another hydroelectric feasibility study, lies 35 miles
to the southeast. Larsen Bay shares wi th other regions of
south Alaska the comparatively mild maritime climate controlled
by the Japan Current that sweeps through the Gulf of Alaska.
This current produces cool summers, mild winters, and moderate
amounts of precipi tation that are well distributed throughout
the year. Most of the precipitation occurs when moist air from
the ocean precipitates as rain or snow as it is uplifted along
the southern slopes of a 2000-to 4000-foot-high mountain range
that extends southwest through the length of the island. Its
primary crest is located 28 miles upwind (south) from Larsen
Bay. Strong continuous winds blow from the south as eastward-
moving Aleutian lows pass through this region from December
through March. No lakes or glaciers remain.
Mean annual precipitation ranges from 20 inches in the most
sheltered coastal locations like Larsen Bay to an estimated 180
inches on some mountain crests (Ott Water Engineers, 1979).
The mean annual temperature of 410F at Kodiak ranges from a
normal daily minimum of 25 0 F in December and January to a
normal daily maximum of 60 0 F in August (Department of Commerce
Environmental Data Service). Mean annual runoff is typically
four cfs per square mile (54 inches) along this leeward portion
of the island. The mean annual low month produces only about
one cfs per square mile of runoff (USGS, 1971).
2. Basin Description
All the previous studies that have considered energy
alternatives at Larsen Bay have chosen Humpy Creek as the
preferred site for potential hydro power development (CH2M
HILL, 1981; Ebasco, 1980; Retherford Associates, 1980; USGS,
1978). The creek is also known as Dora Creek, Trout Creek, or
Larsen Bay Creek, but the local name of Humpy Creek will be
used in this report.
NBI-388-9523-B* 2
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Humpy Creek originates at the north end of a long glacial
trough that forms a hanging valley above Larsen Bay fjord. The
stream flows north for about 4.5 miles. It passes through the
communi ty of Larsen Bay and discbarges into Larsen Bay. The
si te of the proposed power diversion dam (elevation 285 feet
MSL) is one mile south of Larsen Bay at the confluence of the
first tributary that joins Humpy Creek from the southeast.
The drainage area above this si te is 6.28 square miles.
Mountain ridges that flank the drainage basin to the east and
west rise to 2500 feet. The basin divide to the south is an
indistinct rise in the floor of the glacial valley. No lakes
or glaciers remain. Humpy Creek is a comparatively short,
steep stream with characteristics similar to other Kodiak
streams. An old diversion dam, reportedly built in the early
1900s, is located one-half mile upstream from the town. Until
it recently closed, the Kodiak Island Seafoods cannery obtained
its water from this dam through a wood-stave aqueduct. The
small pond behind the dam is completely filled with 10 to 12
feet of sediment. The stream between the old dam and the
proposed diversion is in a narrow, deep canyon with bed
material consisting of gravels, cobbles and some boulders.
Only a narrow discontinuous floodplain has developed within the
canyon. The floodplain and slopes are covered with alders and
brush.
A considerable period of climatological data exists for
Larsen Bay. These data are collected by the Department of
Commerce's Environmental Data Service. A summary of monthly
precipitation is given in Table B-1.
Precipitation in the basin is considerably lower than the
southeast coast basins of the island receive. The mean annual
precipitation for Larsen Bay is 23.01 inches, in contrast to
the 56.71 inches in Kodiak. Precipitation is lower because
Humpy Creek basin is located far down wind from the crest of
NBI-388-9523-B* 3
the primary mountain range. This range causes most of the
precipi tation to fallon its windward slope or wi thin a few
miles downwind of the crest. However, the precipitation within
the drainage basin is expected to be significantly higher than
the 23 inches recorded at the sheltered village site. Based on
National Weather Service and U.S. Geological Service precipita-
tion mapping of the area, the mean annual precipi tation is
about 40 inches. The USGS used existing streamflow data to
determine precipitation isolines; hence, the selected mean
annual precipitation value should approximate precipitation to
be expected in the project basin.
C. DATA UTILIZED
The primary data utilized consisted of the one year of
daily stream flows recorded by the USGS in upper Humpy Creek,
0.7 miles upstream of the proposed power diversion. This gage,
established August 22, 1980, is designated "Larsen Bay Creek
near Larsen Bay, No. 15296480." It is located at an elevation
of 800 feet and measures a drainage area of 3.92 square
miles. In addi tion, the USGS took a number of spot measure-
ments on Humpy Creek near the bay between 1978 and 1980.
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• -USGS streamflow records from numerous gages on Kodiak _
Island were used to establish flow characteristics of streams
similar to Humpy Creek. Much of the data is summarized in the
USGS Hydrologic Atlas for the Kodiak-Shelikof subregion (USGS,
1978) . The 1963 to 1980 dai ly flow records of Myrt le Creek
gage (No. 15297200), located nine miles south of Kodiak, were
used extensively (USGS, 1981). Precipitation records from
Larsen Bay and Kodiak were used indirectly by making appropri-
ate adjustments.
A report by Ebasco (1980) presented flow durat ion curves
from other basins, regional estimating methods, and initial
estimates of basin yield. The CB2M HILL report (1981) depended
NBI-388-9523-B* 4
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principally on the U.S. Geological Survey statewide report
(1971) for flow estimates.
D. PROJECT STREAMFLOWS
w. Humpy Creek is a perennial stream at the site of the diver-
.Mliil
...
sion dam, according to local residents. The flow regime is
seasonal. Higher flows normally occur in May and June from
spring snowmelt and from September into November from rainfall.
A comparison of precipi tation records from Larsen Bay and
Kodiak (Table B-1) indicates that the time distribution of
precipitation is generally similar at both stations. Larsen
Bay has a proportionately drier spring and a somewhat wetter
late summer and autumn than Kodiak.
The most recent preliminary discharge values for Humpy
Creek obtained from USGS and monthly average flows are
presented in Figure B-2. Note that the winter discharge values
are affected by ice when the float of the stage recorder is
frozen. For such periods, the daily discharges were estimated
on the basis of the recorded range in stage or comparison with
the station records from nearby basins .
An examination of the hydrograph for the water year 1980-81
shows two peak runoff periods, May and October. As the
snowpack starts mel ting in April, a slow increase in direct
runoff follows. Peak flows occur in mid May. At the
conclusion of the snowmel t, following a period of low
precipitation (see Table B-1, Kodiak, 1981) in July and August,
the discharge drops to its lowest values. These values reflect
little, if any, contribution from surface runoff. The base
flow, which is the groundwater contribution to the streamflow,
attains a value of four cubic feet per second during this
period. The second peak flow occurs in October as a result of
heavy rainfall that contributes to a rapid increase in direct
NBI-388-9523-B* 5
runoff. The annual peak discharge is typically caused by
rainstorms rather than snowmelt in a small drainage basin with
Ii ttle storage capaci ty such as Humpy Creek. Note that to
estimate the flow at the proposed diversion dam the given
discharges recorded at the gaging station should be multiplied
by 1.60 to correct for the difference in drainage area between
the gage and the dam site.
1. Mean Annual Flow
The mean annual flow for the water year 1980-1981 as
determined from the Humpy Creek gage records is 10.6 cfs for a
drainage area of 3.92 square mi les. For the drainage area
above the proposed dam si te, this value becomes 16.9 cfs. A
check has been made to ascertain whether the observed mean
annual flow is due to a normal, wet, or dry year. The only
long-term precipi tat ion records near the project area are for
the city of Kodiak. Precipitation at the Kodiak station for
the water year 1980-1981 was 75.61, the long-term average
annual precipitation is 56.71 inches. Taking the ratio of
these precipitations (56.71/75.61) provides a flow adjustment
factor of 0.75. If the 1981 mean annual flow of 16.9 cfs at
the dam site is multiplied by 0.75, an estimated long-term mean
annual flow of 12.7 cfs is obtained.
Al though at least a year of discharge record for Humpy
Creek was available for use in obtaining a measured value of
mean annual flow, three procedures for estimating mean annual
flow were applied to help to establish the relationship of the
1981 record to anticipated long-term flows.
NBI-388-9523-B* 6
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These procedures can be categorized into the following
groups:
• modified rational formula
• regional analysis
• channel geomorphology
a. Modified Rational Formula
Application of the modified rational formula is
explained in detail in the Ebasco report (1980). Only the
salient features of the method are provided below. The method
requires that a gaged stream within the study area having
similar weather patterns and groundcover to the ungaged stream
be selected. A proportion is then set up, so that
=
Ag Aug
where Qg and Qug refer respectively to gaged and ungaged
streamflow in cubic feet per second and A is the drainage area.
Factors to adjust precipi tation and elevation data are
incorporated into this equation as follows:
~ug Qg (P) + (~H)E
Aug Ag
where P is the precipitation adjustment factor between the two
watersheds, ~H refers to the elevation differential, and E is
the elevation adjustment factor.
I n applying this procedure, the stream gage records
from Myrtle Creek near Kodiak were paired with Humpy Creek on
the basis of the period of record and of basin and climato-
logical similarity. Mean discharge records of the Myrtle Creek
NBI-388-9523-B* 7
area were analyzed in conjunction with long-term weather
records at Kodiak to determine whether the observed values are
normal or due to runoff from wet or dry series of years. A
flow adjustment factor was derived by taking the ratio of the
average annual rainfalls during a 16-year gaging record to the
long-term average rainfall during the period of weather
records. The resul t ing factor of 0.86 was appl ied to the
shorter-term measured flow of 46 cfs. This analysis yields an
adjusted mean annual runoff of 39.4 cfs or a unit runoff of 8.3
(Qg/Ag in the above equation) for Myrtle cfs per square mile
Creek.
The precipi tation adjustment factor (P) accounts for
the precipitation difference between the area of gaged and
ungaged stream. It is a ratio of long-term average precipi-
tations between the two basins. The precipitation adjustment
factor between Humpy and Myrtle Creek basins is similarly based
on estimates of mean annual basin precipitations. The values
used are 40 inches of precipi tation for Humpy Creek and 140
inches of precipitation (Ott Water Engineers, 1979) for Myrtle
Creek. This resul ts in a precipi tation adjustment factor of
0.285 between the two basins. Using this factor, the adjusted
unit runoff for Myrtle Creek yields a unit mean annual runoff
of 2.37 cfs per square mile for Humpy Creek. The mean annual
flow for the project stream is thus estimated to be 14.9 cfs.
The Ebasco report (1980) estimate of 4.1 cfs per square mile is
much higher. That estimate was based on a pairing with the
gage records from upper Thumb River, which cover a much
shorter, but wetter, period.
b. Regional Analysis
The regional method described by Ott Engineers (1979)
was first applied to the gaged stream Myrtle Creek to test its
applicability. The maritime climate in the Larsen Bay area is
similar to the Chugach National Forest area at the nortbeast
NBI-388-9523-B* 8
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end of Kodiak Island where the method was in part developed;
therefore, the regional method should provide reasonable
estimates.
This method yielded a mean annual flow of 43 cfs with
90 percent confidence limits of 35 and 52 cfs. This predicted
value is within seven percent of the measured flow of 46 cfs.
The same method applied to the Humpy Creek si te with a mean
annual precipitation of 40 inches gives a flow of 13.3 cfs.
The 90 percent confidence limits are 11 ana 16 cfs.
c. Channel Morphology
Channel geomorphology can be used to estimate both the
mean annual flow and the mean annual flood by measuring channel
dimensions that have been shaped by these streamflows. The
method is considered to give reliable estimates for parts of
the United States where estimating relations have already been
defined.
Despite the success of this method at other hydro
feasibility sites and a calibration based in part on streams
located only 15 miles south of Larsen Bay, the estimates for
Humpy Creek were unrealisticly low and therefore they were
discarded.
d. Estimated Flow
A mean annual flow of 13.0 cfs for the Humpy Creek
site is considered to be the best estimate based on available
information and the confidence interval of the various
estimates. The close agreement of the adjusted observed flow
wi th the two estimating methods lends considerable confidence
to the value.
NBI-388-9523-B* 9
2. Flow Duration
The flow duration curve for a potential hydroelectric site
is the initial tool used in sizing the turbine and estimating
annual energy production. Where no continuous record is avail-
able at the si te, the information must be transferred from
gaged sites on the basis of their hydrogeological
characteristics.
The flow duration curve can be viewed as the time dis-
tribution of flows about the mean annual flow; thus a dimen-
sionless flow duration curve (the ratio of flow to the mean
annual flow versus the percentage of time the flow is exceeded)
can be developed for any gaged basin and be directly compared
with any other dimensionless curve. Within certain hydro-
geologic regions these curves often have remarkable similarity,
particularly within the 15 to 80 percent exceedance interval.
Thus, regional curves can be developed. Curves from small,
steep basins with bedrock near the surface and little ground-
water contribution are typically steeper than those from larger
basins that include swamps or lakes and a good aquifer. The
Humpy Creek basin belongs to the former group. A comparison of
dimensionless curves from three basins on Kodiak Island 25 to
40 miles distant and one from Amchitka Island 1200 miles to the
southwest showed considerable similari ty. On this basis the
Myrtle Creek curve developed from 17 years of daily record was
adopted as the type of curve to use for small, mountainous
maritime basins in southwest and south-central Alaska. The
Humpy Creek flow duration curve presented in Figure B-1 is
based on Myrtle Creek, wi th the flows scaled to the ratio of
their respective mean annual flows in cfs (13/46).
3. Annual Hydrograph
Based on the same data and reasoning that went into
determining the mean annual flow and the flow duration curve,
NBI-388-9523-B* 10
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an annual hydrograph can be developed based on monthly flows at
Myrtle Creek.
The Humpy Creek annual hydrograph presented in Figure B-2
and Table B-2 is based primarily on the mean and standard
deviations of the logs of the mean monthly flows recorded at
Myrtle Creek during the 17 years of record. The data are
scaled to-the Humpy Creek si te by the rat io of mean annual
flows. The 1980-81 measured mean monthly flows, adjusted for
the difference in drainage area, were superimposed and showed
good agreement. The range of monthly means shown in gray on
Figure B-2 corresponds to roughly seven out of ten years. Thus
the average monthly flow should lie below the indicated flow
range at least one year in ten and above the indicated flow
range at least one year in ten.
E. DIVERSION WEIR FLOOD FREQUENCY
Estimates of the magnitude and frequency of floods at
remote sites such as the Humpy Creek site must depend primarily
on regional studies. These studies relate the calculated flood
frequency of measured peak flows at gaging stations to drainage
basin characteristics such as area and precipi ta tion by means
of multiple regression analysis.
Estimates of flood discharge at the site were made on the
basis of three previous regional hydrology reports: USGS
(1979), Ott Water Engineers (1979), and Woodward-Clyde
Consultants (1981).
The USGS report employs the log-Pearson Type III distri-
bution to determine flood magnitude and frequency relations on
the basis of data collected at 260 stations throughout
Alaska. Tbe details of the analysis are provided in the
report. The Ott ~ngineers report was developed for the Chugach
and Tongass National Forests on the Gulf of Alaska. The
NBI-388-9523-B* 11
Chugach National Forest includes the east end of Kodiak Island
and the prediction equations developed are considered applic-
able to the Larsen Bay area. The Woodward-Clyde Consul tants
report, written for the City of Valdez, covers much of the same
area of south-central Alaska as the Chugach National Forest
equations developed by Ott Engineers.
The three sets of flood prediction equations were applied
to both the Humpy Creek si te and Myrt Ie Creek, the latter
providing an approximate test for this region.
BASIN PARAMETERS
Site Area Precipe Temperature Percent of Area
(sq.mi.) (in.) (Jan. mean min.) lake store. -forest
Humpy Cr. 6.28
Myrtle Cr. 4.74
40
140
o
o
PREDICTED FLOOD FREQUENCY AT HUMPY CREEK
Method Peak Discharge for Hecurrence
(years) 2 10 25 50
USGS (cfs) 590 890 950 1150
(Standard errors,%) 50 45 48 42
Ott (cfs) 120 250 325 400
Woodward-Clyde (cfs) 250 420
NBI-388-9523-B* 12
o
o
Interval
100
1270
485
520
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PREDICTED FLOOD FREQUENCY AT MYRTLE CREEK
Method Peak Discharge for Recurrence Interval
(years) 2 10 25 50 100
USGS (cfs) 930 1400 1510 1810 2000
Ott (cfs) 665 1110 1300 1480 1670
Woodward-Clyde (cfs) 1130 1470 1620
Based on Lamke I s analysis of 14 years of measured flood
peaks on Myrtle Creek, the 2-year and 10-year floods are 765
and 1020 cfs respect i vely. The maximum flood in that period,
1110 cfs on September 14, 1969, has approximately a 10-year
average recurrence interval.
The mean annual precipitation used at Myrtle Creek is
derived from the isohyetal map produced by Ott. It accounts
for significant increases in precipi tation wi th elevation and
it is similar to the basin precipi tation derived for Humpy
Creek. The USGS method produces much higher estimates wi th
this precipitation value. However, if the mean annual
precipitation of 80 inches derived from the earlier isohyetal
map actually used by Lamke is substituted, the estimated 10-
year flood is 1040 cfs. This appears to be a case where each
method must be confined to the data on which the original
regression analyses were based. With this limitation on
precipitation estimates, there is good agreement among the
three methods.
The adopted flood frequency curve at the Humpy Creek si te
based on the Ott Engineers equations is presented in Figure
B-3. The 90 percent confidence limi ts adapted from the Ott
analysis are also shown. The lines indicate that the true
flood frequency would lie within these limits with a 90 percent
level of confidence.
NBI-388-9523-B* 13
It should be recognized that in this environment the
greatest depth and extent of flooding may not be due to peak
discharges. Ice sheet and ice jam flooding are common. During
the normal winter freeze-thaw cycles, many layers of ice may
accumulate and create temporary ponds that may release suddenly
to inundate and jam the diversion weir.
F. CONSIDERATION OF POT£NTIAL RIVER ICE PROBLEMS
1. Formations of River Ice
The occurrence and condition of the ice on rivers and
reservoirs may require protection of water intake points from
blockage. Several types of ice can form in natural ri vers.
One is called "sheet ice" and it occurs mostly on stagnant
bodies of water and slowly flowing streams. This ice usually
originates wi th plate or border ice and gradually propagates
across the water surface until a continuous sheet is produced.
Another type of river ice is called "frazil ice."
by nucleation of slightly supercooled turbulent
It is formed
water. Two
forms of frazil ice are distinguished: active and passive
forms. Passive frazil ice is not considered as detrimental as
active, which sticks to any solid object at or below freezing
temperature in the river. If the active frazil ice adheres to
the river bottom, it may contribute to the formation of anchor
ice. One other form of river icing refers to a mass of surface
ice formed by successive freezing of sheets of water that seep
from a ri ver. A river icing (to which the term aufeis is
commonly restricted) is more particularly the mass of ice
superimposed on the existing river ice cover.
2. Estimates of Ice Thickness
The thickness a natural ice sheet can attain depends upon
the cooling potential of the atmosphere. In winter this is
NBI-388-9523-B* 14
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often expressed in freezing degree days, and the thickness
reached at any time is expressed in terms of the square root of
the degree days. Although several relationships have been
developed to estimate ice thickness as a function of the
cooling potential of the atmosphere, Stefan's simple equation
( 1889) is ·presented here to provide rough est ima tes of ice
thickness. The Stefan equation in its original idealized form
does not include the effects of snow cover, wind, surface
roughness, and other physical parameters.
expression of Stefan's formula
H=ar-FT
The following
incorporates a coefficient a that presumably accounts for local
effects such as snow cover and snow conditions. Values of a
are given in the following tabulation. FI is the freezing
index and refers to the number of degree days below freezing
for one year. Freezing degree days or freezing index values
are obtained from NOAA climatological records.
For the four small hydropower locations studied for this
contract of which the Larsen Bay Hydroelectric Project is a
part, the following values of a and FI have been chosen and the
resulting river ice thicknesses are indicated.
Site a FI (OF-day) H (inches) ---
Togiak 0.65 2225 30
King Cove 0.40 1400 15
Old Harbor 0.40 1500 16
Larsen Bay 0.40 1400 15
Estimates of river ice thickness are provided to aid the
design of proper hydraulic structures and protect them from ice
problems such as ice jams, icing, and improper placement of the
NBI-388-9523-B* 15
intake. Note that these ice thicknesses are theoretical values
and do not include the effects of wind, flowing water, and
currents and snow cover.
3. Frazil Ice
More severe problems could potentially be experienced from
frazil ice formation at the water intake point. Since very
little is known about frazil ice formation, evolution, and
subsequent disposition, rational design methods to avoid
frazil-ice problems are lacking.
Frazil ice formation has been observed at Midway Creek, Old
Harbor, and Humpy Creek dam site in Larsen Bay. Particularly,
Humpy Creek dam site appears to produce considerable frazil ice
under natural flow condi tions. Del ta Creek dam si te at King
Cove may also experience simi lar ice problems. The Togiak
Quigmy River project site has been observed to have floating
ice blocks and ice jams that develop at naturally constricted
channel locations. During the installation of a stream gage in
December 1981, release of water from an ice-jammed reservoir
upstream caused the stage to rise approximately three feet.
Considerable quantities of floating ice blocks have been
observed following the rise in stage.
While little data are presently available, it is clear that
the potential ice problem ci ted above must be considered in
depth during the design phase of project implementation. These
in-depth considerations should include an evaluation of condi-
tions that cause ice problems, the extent of the problems to be
encountered, and potential measures to alleviate or mi tigate
the problems. About 18 percent of the project energy would be
produced during the coldest winter months from December through
March. If a portion of this energy were lost because of ice
problems, the economic feasibili ty of the project might be
affected. Mitigation measures would be implemented, of course,
NBI-388-9523-B* 16
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to control the problem, but the chance remains that some energy
might be lost. As mentioned, this will be studied in detail
during the design phase of the project •
NBI-388-9523-B* 17
TABLE B-1
AVERAGE MONTHLY PRECIPITATION
(inches)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
La rsen Bay..!./ 2.05 1.92 1.38 1.07 0.76 1.19 1.29 2.82 2.90 3.03 2.37 2.23 23.01
Kodiak,
long term 5.01 4.89 3.85 3.61 4.35 4.12 3.54 4.30 6.11 6.29 5.41 5.03 56.71
Kodiak,
1980-81
Water Year1./ 13.65 6.43 8.05 2.86 7.26 1.87 2.53 4.35 7.47 (9.38) (7.12) (4.64) 75.61
1/ 8 to 15 years of data through 1967. 2/ (October through December) from 1980.
TABLE B-2
ESTIMATED AVERAGE MONTHLY FLOWS AND DEVIATIONS
HUMPY CREEK
(cfs)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Average 7.9 6.8 4.8 9.9 27.4 23.9 9.5 10.6 18.3 17.0 12.8 7.5 13.0
High 24.2 22.5 14.8 20.7 38.6 42.2 20.4 24.2 30.9 28.1 22.8 19.7
Low 2.5 2.1 1.4 4.6 19.3 13.4 4.6 4.6 10.9 10.2 7.0 2.8
NBI-388-9523-Bl
70
60
50
40
30
20
_ 10
f/I ..
o -~
9 ~ 0
\
\
\
\
'" ' ... MEAN ~,NNUAL FLOW 13 cfs
" ~ ,
............... r---... r-----~
o 20 40 60 80 100
PERCENT (%) OF TIME FLOW EXCEEDED
~I~_-----------------------------------------------------------HUMPY CREEK FIGURE
FLOW DURATION CURVE 8-1
LARSEN BAY APPENDIX B
References
CH2M HILL. Reconnaissance Study of Energy Requirements
& Alternatives for Akhiok-King Cove-Larsen Bay-Old
Harbor-Ouzinkie-Sand Point. For Alaska Power Authority, June
1981.
Department of Commerce. ESSA -Environmental Data Service,
Climatological Data Summary, Alaska.
Ebasco Services, Inc., Regional Inventory and Reconnais-
sance Study for Small Hydropower Projects: Aleutian Islands,
Alaska Peninsula, Kodiak Island, Alaska. Vols. 1 and 2,
October 1980.
Grey, B.J. and D.K. MacKay, "Aufeis (overflow ice) in Rivers",
Canadian Hydrology Symposium Proceedings: 79, Glaciology
Division, Water Resources Branch, Inland Waters Directorate,
Environment Canada, 1979.
Michel, B., "Winter Regime of Rivers and Lakes", CRREL
Monograph III-BIA, CRREL, Hanover, New Hampshire, 1971.
Osterkamp, T. and Gosink, J.P., 'Letter written to Dept. of
Commerce and Economic Development', January 1982.
Ott Water Engineers. Water Resources Atlas for USDA Forest
Service Region X, Juneau, Alaska. April 1979.
Rhoads, E.M., "Ice Crossings", The Northern Engineer, Vol. 5,
No.1, pp. 19-24, 1974.
NBI-388-9523-BR
Robert W. Retherford Associates. "Preliminary Feasibility
Designs and Cost Estimates for a Hydroelectric Project Near
Larsen Bay, Alaska." January 1980.
Stefan, J. "Uber Die Tbeorien Des Eisbildung in Polarmere tl ,
Wien Sitzunsber, Adad. Wiss., Sere A, Vol. 42, Pt. 2, pp. 965-
983, 1889.
u.S. Department of Energy, Alaska Power Administration.
"Hydroelectric Power Potential for Larsen Bay and Old Harbor,
Kodiak Island, Alaska." May 1978.
u.S. Geological Survey. tlFlood Characteristics of Alaskan
Streams," Water Resources Investigation 78-129, R. D. Lamke.
1979.
u.S. Geological Survey. "The Hydraulic Geometry of Some
Alaskan Streams South of the Yukon River (Open File Report) ,11
William E. Emmett, July 1972.
u.S. Geological Survey. "Water-Resources Data for Alaska Water
Year 1963 through Water Year 1980-1981.11
u.S. Geological Survey. "Water Resources of Alaska (Open File
Report)"; A. J. Feulner, J. M. Childers, V. W. Norman; 1971.
u.S. Geological Survey. "Water Resources of the Kodiak-
Shelikof Subregion, South-Central Alaska," Atlas HA-612, S. H.
Jones, et al., 1978.
Wabanik, R.J., "Influence of Ice Formations in the Design of
Intakes", Applied Techniques in Cold Environments, Vol 1, pp.
582-597 . 1978.
Woodward-Clyde Consultants. Valdez Flood Investigation
Technical Report. February 1981.
NBI-388-9523-BR
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Yould, P.E., and T. Osterkamp, "Cold Region Considerations
Relative to Development of the Susitna Hydroelectric Project",
Applied Techniques in Cold Environments, Vol. 2, pp. 887-895,
1978.
NBI-388-9523-BR
LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX C
GEOLOGY AND GEOTECHNICS
A.
B.
C.
D.
E.
F.
G.
-
TABLE OF CONTENTS
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TOPOGRAPHY ••• . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REGIONAL GEOLOGY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ENGINEERING GEOLOGY.
1.
2.
3.
Dam Site Geology •••••••••••••••••••••••••
Construction Materials •••••••••••••
Road/penstock/Powerhouse Location ••
SEISMIC HAZARDS ••••• . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MECHANICAL ANALYSES.
REFERENCES CITED ••••
i
1
2
3
6
6
6
7
10
13
16
Figure
1
2
3
4
5
6
LIST OF FIGURES
Geologic Time Scale •.••••••••.•••••••••••••••••
Reconnaissance Geologic Map ••••••••••••••••••••
Road Location Map •••••.•••••••••••••.••••••••••
Seismic Risk Map •••••••••••••••••••••••••••••••
Gradation Outwash Deposit ••••• ~ •••••.••••••••
Gradation -Alluvial Fan Deposit .•.•••••••••••.
ii
page
4
5
8
11
14
15
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APPENDIX C Geology and Geotechnics for the Proposed Larsen Bay
Hydropower pro~ect
A. INTRODUCTION
In siting a hydropower facility, it is important to under-
stand the regional as well as the site-specific geology and geo-
technics. Regional information is necessary to: (1) assess the
geologic hazards, (2) assure that appropriate design criteria are
utilized, (3) discover construction materials borrow sites, (4)
provide background information for environmental studies. This
report discusses regional geology and seismicity and the specific
dam site, penstock/road routes, and the powerhouse location. In
accordance with the Scope of Work for this project, the informa-
tion is intended for use at the detailed feasibility study
stage.
Geologic and geotechnical field studies were conducted
September 18, October 23-25, and November 6-7, 1981, by Dr. R.L.
Burk, project Geologist and Team Coordinator, and J. Finley,
Project Geotechnical Engineer.
-1-
B. TOPOGRAPHY
Larsen Bay is a community located along a bay with the same
name on Kodiak Island, Alaska. Kodiak Island is essentially an
isolated extension of the Kenai Peninsula in the Gulf of Alaska.
Larsen Bay is an arm of the larger Uyak Bay which is a major
north-south trending bay opening to Shelikof Strait between
Kodiak Island and the Alaska Peninsula.
Larsen Bay is now a fjord; however, during glacial times it
was filled wi th ice and was a tributary to the major ice mass
occupying Uyak Bay. Because of the mul tiple glacial advances
that have brought ice to this entire area, the hills are gener-
ally smooth and rounded, hanging valleys are common and valleys
tend to have a parabolic cross section. Elevations in the
immediate area range to approximately 3000 feet. Stagnant ice
topography and abandoned outwash channels are common.
The proposed dam si te is on Humpy Creek, which drains the
hills to the south of Larsen Bay and flows through town into the
bay. The stream is relatively straight and is incised into bed-
rock in the project area.
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C. REGIONAL GEOLOGY
Plate-tectonic theory provides the basic ideas necessary to
synthesize and understand the geology of continental margins and
plate boundaries. Ocean trenches are viewed as si tes of large-
scale underthrusting of oceanic crustal materials. The sediments
that fill these trenches are scraped from the downgoing plate and
accreted to the overlying plate as this underthrusting con-
tinues. Southwestern Alaska has a long history of being a zone
of accretion for deep-sea deposits.
The Kodiak Formation which consti tutes the bedrock under-
lying the Larsen Bay si te has been interpreted as a deep-sea
trench deposi t of Late Cretaceous age (see Figure 1) which has
been accreted to the continent (Connelly, 1978). These rocks are
for the most part marine turbidites and range from well-lithified
siltstones to fine sandstones.
Glaciation on Kodiak Island has probably extended from
Miocene time (Pewe , 1974) to the presen t. The g lac i al depos its
at Larsen Bay date from Late Pleistocene time (Coulter, et al.,
1965). Both till and glacial outwash deposits are present (see
Geologic Map, Figure 2).
-3-
GEOLOGIC TIME SCALE
Subd Ivlslons of GeologIc TIme
Eras PerIods Epochs
(Recent)
Quaternary PleIstocene
u Pliocene
-
0
N MIocene 0 z
LU
U TertIary OlIgocene
Eocene
Paleocene
u Cretaceous -0
N JurassIc 0
en
I.lJ
:::E TrIassIc
PermIan
PennsylvanIan
u MIssIssIppian -
0
N DevonIan 0
LU
~
< Silurian a..
OrdovIcIan
CambrIan
PRECAMBRIAN
(No worldwide subdIvIsIons)
BIrth of Planet Earth
Figure 1. Geologic Time Scale.
-4-
RadiometrIc Ages
(ml II Ions of years
before the present)
1.8
6
22
36
58
63
145 _.
210
255
280
320
360 _. -
415
465
520
580
4,650
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D. ENGINEERING GEOLOGY
1. Dam Site Geology
The geology of this area consists of glacial till, out-
wash, and alluvial fan deposits that mantle bedrock belonging to
the Late Cretaceous Kodiak Formation (see Geologic Map,
Figure 2). The bedrock is a slate with poor to moderate fissil-
ity. There appears to be some gradation in size of the original
sediment, which is consistent with the turbidite classifica.tion
of these rocks by Connelly (1978).
The proposed diversion weir is in a very narrow gorge
within the bedrock. The walls of the gorge are near vertical in
many areas along the stream and at the dam site. Other than
removing minor amounts of loose rock at the surface, no special
problems are anticipated for dam abutments. The rock is not
highly weathered or fractured and appears competent for this
use. Stream gravels at the proposed dam site are virtually non-
existent.
Permafrost is not present in this area. No springs or
unusual groundwater condi tions were observed at the si te during
field work •
2. Construction Materials
Gravelly sand is present both in the outwash deposi t
(see Geologic Map, Figure 2) and the alluvial fan deposit.
Gradations are shown in the Mechanical Analyses Section,
Figures 5 and 6. rrhe fan deposi ts are probably superior for
-6-
construction because there is an existing gravel pit (also the
city dump) which can be used. If higher quali ty materials are
required, beach materials should be investigated.
The rock that is blasted away for road construction
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should provide adequate riprap for weir construction and stream _
crossings, if they are necessary. -
3. Road/Penstock/Powerhouse Locations
There are two potential locations for the penstock and
road: one on each side of Humpy Creek (see Road Location Map,
Figure 3). Both of these locations involve a number of geotech-
nical problems in terms of slope stability, river channel cross-
ings and bedrock excavation.
An adequate road currently exists up to the present dam
across Humpy Creek. This road ends near the west abutment of that
dam. option A could ei ther cross the creek at the wei rand
connect with the existing road or extend down the east side of
the creek to town. option Bb would connect with the existing
road and stay on the west s ide all of the way to the proposed
diversion site. From the staging area (see Figure 3), both op-
tions are identical and require a roadbed to be blasted into the
bedrock.
Up to the point where the road would drop down to the
stream, option A is very inexpensive to build, with few geologic
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hazards and little likelihood of future major maintenance •
problems. Once the road reaches the stream, either one (Alterna-
tive Aa) or three (Alternative Ab) stream crossings, depending on
the amount of blasting, are necessary to reach the staging area.
-7-• •
•
II1II
Option Aa would need approximately 125 feet of blasted road and
one stream crossing to reach the staging area and Option Aa would
require three stream crossings and no blasting.
Option Bb extends from the dam up a gentle slope de-
veloped on glacial till. From there it crosses a 60 percent side
slope composed of outwash, which would be difficult to cut back
because of its height. After approximately 500 feet on the side
slope, the route crosses landslide deposits with springs issuing
from them and then follows a low terrace until just before the
staging area. To go from the terrace down to the staging area,
it will be necessary to cut into the bedrock along a section
approximately 200 feet long.
Of the two options,
cutting back into the slopes.
better option. It also does
Option A requires a minimum of
From that standpoint, it is the
not cross any areas of major
hillslope failure.
The proposed powerhouse is located on inactive alluvial"
fan deposits with good bearing capacity. No special geotechnical
problems are anticipated at that site.
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E. SEISMIC HAZARDS
Southwestern Alaska is part of an intense seismic zone which
circumscribes the Pacific Ocean. Most of the more than 150,000
earthquakes that occur worldwide each year occur in this Circum-
Pacific belt and in a somewhat smaller belt which extends through
southern Asia and the Mediterranean.
Past earthquake damage in the study area has been princi-
pally manifested in five separate forms which can act independ-
ently or in combination.
o
o
o
Surface faulting -faults are present in the Lar-
sen Bay area: however, the rock at the proposed
dam sites does not appear to have been subject to
fault slip. There is no evidence of faulting
along the penstock/access route or at the power-
house site.
Strong ground motion over a 50-year design
period, the maximum rock acceleration is expected
(probability of exceedance = 10%) to be between
40 and 50%g (see Figure 4). This figure was pre-
pared using actual earthquake epicenter and
magnitude data for Alaska.
Ground failure -minor landslides have occurred
in this area in the past; however, no major
slides that would affect the integrity of a dam
or powerhouse are expected. The site is in
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bedrock. The access road and penstock is in part
on glacial drift, however no special ground
failure problems are expected.
Seiches -these are long-period oscillations of
enclosed water bodies. Because no reservoir is
proposed, no destructive seiches are expected.
Tsunami -seismic sea waves could affect coastal
areas, including the town of Larsen Bay but not
the diversion site.
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F. MECHANICAL ANALYSES
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® Alaska Testlab 4040 "B" Street Anchorage, Alaska 9950] Phone (907) 278-1551
Textural Class~ ____ Grav~)}·X_?_a~<!~~~ __ ~_~_~ _____ ~ Client ________ ~A:.laska_~ower
Frost Class _~ ____ ~ _________ Unified Class SW ______ ~
Plastic Properties _________________ ~ ______ ~_~ ___ ~ _________ ~
Project _____ ~~~s~Jl ___ Bay
Sample Number ___ ,3985 __
Date Received 11 !9/8l~ ________ ~ ________ _ Location ______ ~ ____ ..Bl~_RB.:_a _
Sample Taken By Cl j ent
Sheet 2 of 2
W.O. No. D134~
Date _~~11/9/81
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Figure 6.
Alluvial Fan
Deposit
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G. REFERENCES CITED
Connelly, W. 1978, Uyak Complex, Kodiak Islands, Alaska: A
Cretaceous subduction complex: Geological Society of
America Bulletin, v. 89, p. 755-769.
Coulter, H.W., and the Alaska Glacial Map Committee, 1962, Map
showing the extent of glaciations in Alaska: u.S. Geologi-
cal Survey Map 1-415.
Pewe, T.L., 1975, Quaternary Geology of Alaska: u.S. Geological
Survey Professional Paper 835, 145 p.
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LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX D
DETAILED COST ESTIMATE
,.,.
-TABLE OF CONTENTS
-PAGE
-A. GENERAL 1
-B. METHODOLOGY 2
-C. MOBILIZATION AND SUPPORT COSTS 3
D. UNIT PRICES 4
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NBI-426-9523-TC
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APPENDIX D
DETAILED COST ESTIMATE
A. GENERAL
This appendix presents the method, backup data, and
assumptions used to estimate the cost of the recommended
hydroelectric project. Following the presentation of the
methodology are tables showing a breakdown of major cost items
such as mobilization, labor and transportation.
At the outset of the cost estimating procedure for the
Larsen Bay Power Project, it was determined that the unit-cost
estimating method for material placement and other construction
activities
confidence .
would not provide sufficient accuracy and
Development of construction cost estimates with this method
uses unit prices developed from estimates and bid tabulations
on similar projects under similar conditions, in terms of geo-
graphic location, weather, accessibility and other factors that
may affect the cost. When available unit prices are not
similar in these respects, they must be adjusted to reflect the
actual cost of the construction items under the specific
conditions. For this project, it was felt that the available
data base of unit prices was not sui tabl e. Typically, un i t
prices on remote Alaskan construction projects vary widely and
seem to depend heavily on a contractor's approach in scheduling
crews, transportation, shipping, and work schedules.
NBI-426-9523-AD 1
The cost estimate herein was prepared by using the heavy-
construction estimating method and January 1982 costs. This
method treats the project as a separate entity. The construc-
tion cost computations are based on the use of construction
equipment units, labor rates, labor productivity, working
conditions, work schedule and sequence, subcontract prices,
permanent material and equipment prices, and special con-
straints and requirements.
B. METHODOLOGY
The preliminary design and layout of facilities was used to
establish estimated quantities of permanent and consumable
materials and other measurable items of work such as excavation
and embankment quanti ties. A construction schedule was pre-
pared for each major item of work, based on assumed production
rates normally attainable under similar conditions. Considera-
tion was given to the remote location, 60-hour work week, and
short construction season. Construction equipment of
appropriate size and type for each operation was selected with
a view toward minimizing the number of pieces of equipment and
using each piece to its optimum capacity.
The manpower from the standpoint of crafts and the numbers
of persons; hours of equipment operation; Quantities of
consumable supplies and spare parts; subcontracted work; and
the required permanent materials and equipment were estimated
for each work i tern. The appl icabl e rates and pr ices were
applied to produce direct costs of labor, equipment, and
materials.
It was assumed that all skilled construction personnel will
be brought to the site by the contractors since it is not known
whether local I abor will be avai I abl e. Tabl e 0-1 I ists the
skilled personnel that will work on the project, and tabulates
NBI-426-9523-AD 2
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the number of man-weeks required for each craft. Also
ind ica ted is the weekly wage for each craft. The wages are
based on union scale, including benefits, current as of January
1982. A work week (man-week) consisting of six ten-hour days
is assumed. If the contractor chooses to increase the number
of working hours per man-week, the weekly wage will increase,
but the overall labor cost will not, since the duration of the
construction period will decrease accordingly.
Also included in the work force are subcontracted person-
nel. A heavy equipment moving crew will transport the
turbine/generator assembly from the barge unloading site to the
project site and install it in the final position. An erection
crew will assemble and install the prefabricated metal
powerhouse building on the concrete foundation.
The transmission line subcontract labor force is not
included in Table 0-1 and is excluded from the labor cost;
however, the required camp cost to support this crew of eight
is shown. A detailed breakdown of the transmission line
subcontract is presented in Table 0-8. The subcontract amount
is based on January 1982 costs for power lines connecting the
potential hydroelectric si te to existing village power
plants. Loads and distances can easily be handled with
distribution vol tages (12.47 kV). Therefore, popular REA-type
assemblies and conductors were assumed. A typical crossarm
construction assembly is shown on Plate VI, Appendix A.
Equipment costs presented in Table 0-2 are based on an
hourly ownership rental for 21 weeks plus an hourly use rate
for the actual hours used. The rates used are from actual
costs of operating,
include fuel costs
owning, and maintaining equipment. They
at Alaskan rates. Material costs are
current costs for the items delivered to Seattle, Washington,
at a barge departure point. They are shown in Table 0-3.
NBI-426-9523-AO 3
C. MOBILIZATION AND SUPPORT COSTS
Due to the remote location of the site, essentially all of
the equipment, vehicles, and supplies required to construct the
project will be transported to and from the si te by barge.
Barges can operate from several points, including Seattle and
Anchorage. The actual departure point would depend on the
contractor's particular situation. This cost estimate is based
on a barge departing Seattle in late April or early May, using
material prices FOB Seattle and barge rates from Seattle to
Larsen Bay (see Table D-4.) Barge time to the project site is
approximately two weeks. Table D-4 summarizes barge shipping
costs both to and from Larsen Bay.
The construction workers and supervisory personnel will be
housed in a construction camp set up specifically for this
project. Table D-5 shows the overall cost, based on a uni t
cost per person-day assuming that each man-week of labor will
require support for one person for seven days. The cost
includes mobilization and demobilization of the camp and all
other supportive costs.
Ai r t ransporta tion support costs are shown in Table D-5.
These costs cover the trips that would be required for a
project of this nature and an anticipated personnel turnover
rate of about 20 percent.
Table D-6 is a summary of all direct costs associated with
the construction of the Larsen Bay project. A contingency of
15 percent and a markup of 15 percent for contracor overhead
and profit are included. The cost of the transmission line is
based on a subcontract cost that incl udes a cont ingency. As
ind ica ted, it is marked up by 10 percent to cover the prime
contractor's indirect expenses associated wi th scheduling and
NB I -426-9523 -AD 4
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responsible supervision.
administrative costs are
cost.
,D. UNIT PRICES
Engineering and owner's legal and
added to produce a total project
Figure D-l is a construction schedule for the Larsen Bay
Power Project. Based on a detailed analysis of the construc-
tion activities and the information presented in Tables D-l
through D-5, all of the direct costs were assigned to an
appropr ia te category that represents a major item of work.
Unit prices were calculated and these are presented in Table
D-7. They take into account the assumptions previously used
for production rates, support equipment, and supervisory
effort. Page 2 of Table D-7 details the content of the various
cost headings and item descriptions.
Finally, a detailed breakdown of uni t prices, quanti ties,
and total cost is presented in Table VI I I -1. These are based
on the average unit costs for major categories presented in
Table D-7 and modified to take into account the quantities,
scheduling, and location within the project area of the
specific item of work. Therefore some unit prices may vary for
the same items used on different phases of the work.
Note that the cost estimate prepared for this project was
not based on the unit-cost method. The unit prices presented
in this report are intended for use in presenting the general
relationship and magnitude of the major construction items for
this particular project. They should not be used out of
context because they may not accurately represent the cost of
performing similar work at other sites or under different
circumstances.
NBI-426-9523-AD 5
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TABLE 0-1
LARSEN BAY
LABOR BASED ON 60 HR. WEEK
Labor Cost/
(Man-Weeks) Week Total Cost
General Superintendent 17 $1,986 $33,762
Superintendent (Cr ew A) 10 1,758 17,580
Operators (Crew A) 25 1,730 43,250
Oilers 10 1,575 15,750
Mechanics 10 1,730 17,300
Laborers (Crew A) 38 1,571 59,698
Dr i 11 e r / Po wd e r Man 3 1,603 4,809
Superintendent (Crew B) 10 1,986 19,860
Electrician 5 1,850 9,250
Ironworkers 5 1,840 9,200
Carpenters 9 1,637 14,733
Apprentice Carpenter 9 1,571 14,139
Operators (Crew B) 18 1,730 31,140
Millwrights 3 1,800 5,400
Finishers 4 1,571 6,284
Welders, Fitters 2 1,897 3,794
Laborers (Crew B) 31 1,571 48,701
Manufacturer's Rep 3 10,000
Line Crew (8) 16 Subcontract
K. D. Bldg. Crew (3 ) 3 Subcontract 10,000
Heavy Equipmen t Moving Crew 3 Subcontract 25,000
TOTALS 234 Man Weeks $399,600
NB 1-411-9523 -0-1
CAT-D8K
Front End Loader 966D
Flatbed Truck
Dump Truck (10 yd)
Service/Fuel Truck
Airtrack/Compressor
Pickup Truck (2 ea)
Backhoe -CAT 225
Welder
Generator
Generator Spare
Hand Compactors (5 ea)
Conc. Mixer Trailer
Small Mixer (3 ea)
Screening Plant
3" Water Pumps (3 ea)
Fuel Tank, Bladder
Cutting Torch, Set
Misc. Equipment
Pole Setting Truck
Line Truck
Office Trailer
TABLE D-2
LARSEN BAY
EOUIPMENT COST
Ownership Total Hourly
Expense Operating Operating Operating
(23 wks) Hours Cost Cost
$67,600 340 $103.22 $35, 100
18,800 240 30.06 7,210
4,100 240 14.57 3,500
8,350 240 16.87 4,050
10,850 360 17.20 6,200
23,350 180 27.00 4,860
3,250 ea 300 ea 12.69 ea 3,800 ea
24,900 300 20.37 6,110
1,100 80 5.51 440
510 540 .94 500
510 100 .94 100
1,800 ea 75 ea 1.00 ea 75 ea
2,000 125 2.50 310
250 ea 50 ea 1.00 ea 50 ea
9,300 220 23.75 5,225
500 ea 240 ea 1. 00 ea 240
5,000
300
2,000
Costs contained in transmission subcontract
3,000 600 1. 68 1,000
TOTAL
Total
Cost This
Project
$102,700
26,010
7,600
12,400
17,050
28,200
21,170
31,010
1,540
1,010
600
5,625
2,310
900
14,525
2,220
5,000
300
2,000
4 2 °00
$286,510
NBI-411-9523-D-2
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TABLE 0-3
LARSEN BAY -MATERIAL FOB SEATTLE
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Uni t
Item Quantity Uni t Price Amount ---
1. Cement Type I 1,840 Bags $ 4.73 $8,703
-2. Reinforcing Steel 21,160 Lb 0.35 7,406
3. Fiberglass Pipe -27" 2,475 Ft 44.30 56,483
' .... 4. Steel Pipe -27" 1,425 Ft 45 64,125
5. 27" Dresser Coupl ings 36 Ea 300 10,800 ....
6. Welded Ring Girder 66 Ea 75 4,950
. ~4'i 7 • Prefabricated Steel
Uni ts
Steel Dam, 1,100 Lb 1. 50 1,650
Offtake Structure 3,500 Lb 1. 50 5,250
Sed imen t Basin 8,000 Lb 1. 50 12,000
.... 8 . Turbine Generator Assy.
Includes Switchgear 1 Ea 320,000
9. Electrical & Mechanical
Accessory Equipment
and Materials 1 Lot $46,000 $46,000
.... 10 . Culvert Materials -50' 780 Lb 1.00 780
11. Blasting Powder 4,405 Lb 1. 00 4,405
, .. it 12. Steel B u i 1 din g Ki t 1 Ea 25,000 25,000
13. Forming Materials 1 Lot 7,500 7,500 -14. Misc. Structural Steel 1,300 Lbs 0.30 390
-MATERIALS FOB SEATTLE DOCK $575,500
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NBI -411-9523 -0-3
Haul
Class
A
B
C
0
E
F
G
H
I
J
I
J
Commodity
Structural
Palletized
Lumber
Poles
TABLE 0-4
LARSEN BAY
BARGE SHIPPING COST
Seattle To Larsen Bay
(Typical) Weight (lb)
Steel 42,140
Cement 172,960
7,500
7,700
KO Metal Bldg 15,000
Steel Pipe, Cuvert 101,080
Misc. Wire, Hardware,
etc. 24,105
Fiberglass Pipe 30,850
Large Equipment,
M~chinery 390,500
Trailer 12~000
TOTAL
($/cwt)
8.24
6.93
8.00
8.00
12.50
8.24
24.32
16.48
12.00
25.00
Larsen Bay to Seattle (Return)
Large Equipment,
Machinery 301,000 12.00
Office Trailer 12~000 25.00
TOTAL
NBI-411-9523-0-4
Cost ($)
3,472
11,986
600
616
1,875
8,329
5,860
5,084
46,860
3~000
$87,690
36,120
3~000
$39,120
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ESTIMATE OF CAMP COSTS
226 Man-Weeks
TABLE 0-5
LARSEN BAY
Each week the men are supported for seven days
226 x 7 or 1582 days @ $135 per day
CAMP COSTS TOTAL
ESTIMATE OF AIR TRANSPORTATION COSTS
Bring in crew and small tools -assume 6 men per
flight and 24 men with a Beech King Air.
4 Trips Anchorage to King Cove and back
@6 hrs/round trip
4 Trips @ $2500
Approximately 1500 lbs of freight via Reeve
Aleutian and Air Taxi twice a week
3000 lbs @ $0.75/lb or $2250 per week
10 Weeks @ $2250
40 One Way Trips during construction for per-
sonnel changes & supervisor visits
32 Trips @ $282
Misc. Supply Trips
4 Trips Queen Air Cargo
Remove crews at job close
AIR TRANSPORTATION TOTAL
NB I -411-9523 -0-5
$213,570
$10,000
22,500
9,024
10,000
10,000
$61,520
Material FOB Seattle
Labor
TABLE D-6
LARSEN BAY
SUMMARY SHEET
Transportation -Barge to Site
Transportation -Barge to Seattle
Transportation -Air
Camp Costs -Catered
Equipment Cost
Prime Contractor 15% Profit
Contingency 15%
Transmission Line -Electrical
Labor & Materials Subcontract
Prime Contractor 10% Markup
Surveying, Right-of-Way & Geology
Engineering Design
Construction Management
Owner's Legal & Admin. Costs 3%
Subtotal
Subtotal
Subtotal
Subtotal
GRAND TOTAL
NBI-411-9523-D-6
$ 575,500
399,600
87,690
39,120
61,520
213,570
286 2 510
1,663,500
249 2 520
1,913,020
286,950
172,000
17,200
2,389,200
50,000
175,000
125 2 000
350,000
82 2 200
$2,821,400
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TABLE D-7
LARSEN BAY
( I
DEVELOPMENT OF AVERAGE UNIT PRICES FOR MAJOR ITEMS OF WORK
1/ Material Labor Equipment Contractor Total
Item Cost Cost Cost Profit (15% ) Amount Quantity
1-Mobil/Demob. $151,90oY $ 73,600 $ 54,090 41,950 $321,600
2. Penstock -Steel 88,730 46,720 13,980 22,410 171,840 1,425
3. Penstock -Fiberglass 61,560 42,660 47,240 22,720 174,180 1,275
4. Rock Exc. 4,410 62,620 154,020 33,160 254,210 4,671
5. Road Exc. , Conunon 0 4,600 13,410 2,700 20,710 600
6. Culvert Pipe 840 1,200 1,000 460 3,500 50
7. Gravel Fill -Road 0 8,200 5,700 2,090 15,990 630
8. Concrete 37,470 158,660 14,880 31,650 242,660 185
9. Transmission LineY 2,080 15,120 0 2,580 19,780
10. Prefab Steel Bldg. 26,880 12,840 1,420 6,170 47,310
11. Turbine & Generator 369,990 135,990 8,030 77,100 59,110
12. Prefab Steel Structures 19,950 17,850 5,800 6,540 50,140 12,600
TOTALS $249,520 $ 1 , 91 3 , 02 o.!!
1/ These items are described on page 2 of this table. 2/ Includes Barge and Air Support Costs only.
3/ Includes costs over and above subcontract amount only. 4/ Amount corresponds with second subtotal on Table D-6.
NBI-411-9523-D-7
Unit
Unit Price
LS $
LF 121
LF 137
CY 54
CY 35
LF 70
CY 25
CY 1,312
LS
LS
LS
LB 3.98
ITEM
1. Mobilization/Oemob
2. Penstock, Steel
3. Penstock, Fiberglass
4. Rock Excavation
5. Road Exc. , Common
6. Culverts
7. Gravel, Road
8. Concrete
9. Transmission Line
TABLE 0-7
(Cont'd)
Includes general supervIsIon, barge and air support costs, staging
equipment, miscellaneous standby equipment, etc.
Installed, including couplings, ring girders, excavation & back-
fill (unclassified).
Installed, including bedding, excavation & backfill (unclass-
ified) .
All, including road, penstock route and structural.
Unclassified road excavation, including placement as fill where
used.
Installed.
Road fill, borrow, including haul.
All, including equipment, material, cement, forming, miscellaneous
structural excavation (unclassified) & reinforcing steel.
Installed -Subcontract plus shipping, and camp costs.
10. Prefab Steel Bldg. Installed.
11. Turbine & Generator Installed, including mechanical, electrical, and startup.
12. Prefab Steel Structures Installed, including structural excavation for diversion dam.
COLUMNS
Material Cost Material cost FOB Seattle plus shipping.
Labor Cost Salary at 60 Hrs/week plus subsistence costs.
Equipment Cost Ownership rental plus use rental, based on six months.
NBI-411-9523-~7
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TABLE D-8
LARSEN BAY
BREAKDOWN OF TRANSMISSION LINE SUBCONTRACT
Item
Poles
Crossarms, Insulators & Guys
Wire
Subtotal, Overhead
Transformers, Pads &
Sectionalizing Equipment
Subtotal
Contingency: 25% Labor
10% Materials
Subtotal
Equipment Mobilization
Misc. Crew Transportation
& Supervision
Total
Say
Material
Cost
2,800
2,285
2,218
7,303
39,800
47,103
Laborl.!
Cost
11,900
6,450
11,880
30,230
22,100
52,330
Total
Cost
14,700
8,735
14,098
37,533
61,900
99,433
13,083
4,710
117,226
50,000
4,800
172,026
$172,000
1/ Based on 75 $/man hour and 425 $/crew hour for a 5 man
crew, including: 1 backhoe, 1 line truck with digger, 1
crew cab pickup, and wire stringing equipment.
NBI-411-9523-D-8
i
Activity
I. Barge T rave I
2. Mobllization/Demobi Ilzatlon
a. Set Up Camp/Demobilize
b. Stage Material
3. Road Construction & Penstock Route
4. Penstock Construction
a. Underground
b. Steel
c. Testing
5. Powerhouse
a. Concrete Work
b. Set Turblne-Generator
c. Erect Building
d. Mechanical & Electrical
e. Startup
6. Diversion Site
a. Concrete Work
b. Set Prefab Steel
7. Cleanup
8. Transmission Line
I I
FIGURE 0-1
LARSEN BAY CONSTRUCTION SCHEDULE
Week
2 3 4 5 6 7 8 9 10 11 12 13
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LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX E
ENVIRONMENTAL REPORT
_.
-
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,...
-
A.
B.
C.
D •
E.
F.
G.
H.
I.
J.
K •
L.
M.
N.
O.
P.
Q.
R •
S.
T.
U.
V.
W.
x.
PROJECT DESCRIPTION
SCOPE OF WORK
HYDROLOGY
FISHERIES
TABLE OF CONTENTS
CURRENT UTILIZATION OF FISHERY RESOURCES
PHYSICAL STREAM DESCRIPTION
FISHERY H1PACTS
FISHERY MITIGATION
WILDLIFE
CURRENT UTILIZATION OF WILDLIFE RESOURCES
ENDANGERED SPECIES
WILDLIFE IMPACTS
WILDLIFE MITIGATIO~
VEGETATION
ARCHAEOLOGIC AND HISTORIC SITES
POTENTIAL VISUAL IMPACTS
IMPACT ON RECREATIONAL VALUES
AIR QUALITY
SOCIOECONOMIC IMPACTS
LAND STATUS
PERMITTING REQUIREMENTS
RECOMMENDATIONS
REFERENCES CITED
PERSONAL COMMUNICATIONS
i
• ••• e.
Page
1
1
3
5
6
7
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9
10
11
20
20
22
23
24
24
24
24
25
26
27
30
31
31
Figure
1
Tables
1
2
3
4
LIST OF FIGURES
Project Location Map
LIST OF TABLES
Water Quality Data, 1981 3
Species and Number of Fish Caught in Humpy Creek 5
Terrestrial Mammals of the Kodiak
Island Archipelago ••••••.••••.••••.••••..•••.• 12
Birds of the Kodiak Island Archipelago 13
LIST OF PHOTOGRAPHS
Photographs
1 Proposed Dam Site
2
3
4
Cannery Dam, Built in 1923 ....................
Stream Section Between the Proposed Powerhouse
Site and the Existing Dam ...••.••••.••••.•••
Intertidal Zone, Humpy Creek ..................
ii
2
2
8
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A. PROJECT DESCRIPTION
A diversion weir is proposed at an elevation of 325 feet
(MSL) on Humpy Creek for a run-of-the-river hydroelectric proj-
ect with a power output of 270 kilowatts. Water would be
diverted into a penstock, leading to the powerhouse located
just below the old cannery dam. A trail, passable by three-
wheeled vehicles, will be constructed from the powerhouse to
the diversion weir. A transmission line will lead from the
powerhouse to Larsen Bay.
B. SCOPE OF WORK
As contracted with the Alaska Power Authority, environ-
mental studies were to include an initial two-day reconnais-
sance visit, followed by a three-to four-day trip for more de-
tailed studies. Li terature review and discussion with local
residents and agency members were to be combined with field
studies to obtain information on fish and wildlife resources in
the area and effects of the project on these resources •
Hydrology, land status, archaeologic and/or historic
sites, and permitting requirements were to be briefly dis-
cussed, as well as impacts on recreational values, air quality,
socioeconomics and scenic viewpoints.
The reconnaissance visit occurred on September 18, 1981,
and a more detailed site investigation occurred October 23-24,
1981. Humpy Creek was walked for most of its length and minnow
were traps placed in selected locations. Numbers and locations
of wildlife and wildlife sign were noted. Local residents were
contacted through a community meeting on September 20, 1981,
and through discussions with individual s during both visits.
Photos 1 and 2 show the proposed dam site on Humpy Creek and
the abandoned cannery dam.
-1-
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The Alaska Power Authority held an informational meeting
to discuss four potential hydropower sites, including Larsen
Bay, with interested federal, state and local organizations in
Anchorage on October 21, 1981. Additional contacts were made
by DOWL with state and federal agencies on an individual basis
during September, october and November.
C. HYDROLOGY
Humpy Creek originates from the mountainous terrain south
of Larsen Bay and flows in a northerly direction through the
communi ty of Larsen Bay. The creek is about 4.5 miles long.
It discharges into Larsen Bay after draining an area of 6.28
square miles at the proposed dam site.
A year of streamflow data exists for Humpy Creek. The
long-term mean annual flow is estimated to be 12.7 cubic feet
per second at the dam site. Based on the discharge records,
May and October appear to be peak runoff periods: the former is
due to snowmelt and the latter is due to rainstorms. The base-
flow, which is the groundwater contribution to the streamflow,
ranges from cubic feet per second and occurs in winter and dry
summers (July and August). The mean annual flood can exceed 60
cubic feet per second. Additional information on hydrology can
be found in Appendix B.
Water quality information for Humpy Creek is given in
Table 1, and sampling locations are shown in Figure 1.
Date
10/24
10/24
TABLE 1
WATER QUALITY DATA, 1981
Location
Temp. D.O.
(oC) ~ (mg/l)
Cannery Dam 4.1 7.2 12.8
Above the Culvert 4.8 6.7 12.2
-3-
Conductivity
Micromhos/Cm
56
55
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Hfit
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--
D. FISHERIES
Alaska's Fisheries Atlas, Volumes I & II (ADF&G, 1978a),
lists pink salmon and Dolly Varden char as the only fish spe-
cies present in Humpy Creek. Local residents confirmed this
information. Ken Manthey, Kodiak Area Management Biologist
(personal communiciation, 1981), stated that runs of pink sal-
mon occur each year, but that the strongest run occurs during
odd years. Escapement counts for Humpy Creek have been sporad-
ically taken by ADF&G. In 1977, 12,075 pinks were counted
during a foot survey, and in 1981 600 pinks were counted in an
aerial survey.
Approximately 25 adult pink salmon were observed in Humpy
Creek above the culvert on September 18, 1981. Dolly Varden
char were caught in minnow traps throughout the stream, and
juvenile silver salmon were caught in two locations (Table 2).
TABLE 2
SPECIES AND NUMBER OF FISH CAUGHT IN HUMPY CREEK
October 23-24, 1981
Location Juveniles Caught
30 yards above the road 4 Dolly Varden
10 silver Salmon
230 yards above the road 11 Dolly Varden
400 yards below existing dam 20 Dolly Varden
23 Silver Salmon
200 yards below existing dam 5 Dolly Varden
100 yards above existing dam 1 Dolly Varden
Pink salmon normally spawn intertidally or in the
lower reaches of short coastal streams. Medium-sized gravel
-5-
(0.6 to 0.3 inch) is preferred, with an optimum stream flow
velocity for spawning of 0.1 ft./sec. or greater (ADF&G,
1978a). In Humpy Creek, it appears that most of the spawning
.occurs intertidally and within the first 100 yards above the
culvert of the road. Local residents stated that only in years
with large runs do a few pink salmon get upstream as far as the
diversion dam. This dam, built in 1923, has a 10 foot fall
that prevents upstream fish passage. Pink salmon migrate to
saltwater immediately upon emergence.
Silver salmon generally spawn at the head of riffles in
shallow, swift flowing streams or tributaries.
flow velocity during spawning is 3.4 ft./sec.
Optimum stream
(ADF&G, 1978a).
When first emerged, juvenile silvers frequent near-shore areas
wi th gravel substrates. Older juveni les prefer deeper pool s
and avoid riffle areas. In Humpy Creek, juvenile silvers occur
predominately in still or slow-moving water.
Dolly Vardens spawn in medium to large gravel (1.3 to
0.3 inches) in a fairly strong current, usually near the center
of the stream in at least a foot of water (ADF&G, 197 8a) .
Juvenile Dolly Vardens are relatively inactive, often remaining
on the stream bottom in pools or eddies under rocks and logs or
undercut banks. Dolly Varden occur in both anadromous and non-
anadromous populations. If anadromous, juveniles spend three
to four years in their natal stream before entering saltwater.
E. CURRENT UTILIZATION OF FISHERY RESOURCES
Larsen Bay residents have traditionally gathered a large
portion of their diet from the sea and they continue to do so
today, al though to a lesser extent. Al though no figures are
available for the total annual catch, local residents indicated
that a subsistence harvest for pink salmon occurs in Humpy
Creek.
-6-
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• ..
• •
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• •
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• •
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• •
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• •
• ...
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• •
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F. PHYSICAL STREAM DESCRIPTION
Humpy Creek can be divided into two sections based on the
type of fishery habitat. Section 1 extends from the headwaters
to about 100 yards below the existing dam. Section 2 includes
all portions of the stream below this point. Photos 3 and 4
show Humpy Creek in the proposed project area and in an inter-
tidal zone.
In Section 1, the stream flows through a lOa-foot wide
gorge with steep gradients. The streambed is primarily com-
posed of boulders and bedrock shelves, with intermittent
pockets of gravel. Behind the dam, deposited gravel and sand
extend 150 feet upstream. The deposits have built up to within
three feet of the top of the dam.
The lower stream (Section 2) has a slower flow velocity
and a gravel substrate of slate fragments. Substrate size
ranges from sand to cobbles six inches in diameter, with a
median size of one to two inches. Above the cuI vert, the
frequently undercut banks are lined with grass and willow. The
stream width varies from 6 to 10 feet and the maximum depth is
approximately 18 inches. Below the bridge, the stream is tid-
ally influenced, and forms a broad channel with a maximum depth
of approximately eight inches.
Humpy Creek has no established use as navigable or public
waters.
G. FISHERY IMPACTS
Construction activity may temporarily increase erosion and
sedimentation in Humpy Creek. Sedimentation could affect fish
by interfering with or preventing respiration of incubating
eggs, through loss of spawning gravel, and through physical
-7-
.....
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disturbance to both adult anadromous fish and resident species.
These effects could lead to a decrease in returning salmon runs
to Humpy Creek. However, proper construction techniques and
timing can minimize these impacts.
The portion of Humpy Creek between the diversion weir and
the powerhouse may be dewatered during low flows, and a major
reduction in flow will occur during plant operations. This
reduced flow may seasonally prevent fish from util izing this
stream section. The diversion weir will also prevent passage
of resident fish. However, impacts are considered to be minor
since onl y small numbers of Dolly Vardens were found in this
section of the stream.
No changes in water quality are anticipated due to opera-
tion and maintenance of this power project.
H. FISHERY MITIGATION
The following measures should be followed to reduce ero-
sion and sedimentation of area streams:
Construction should be done during a single sum-
mer. This should reduce the opportunity for ero-
sion of exposed soil.
Instream work should be scheduled during low
flow periods to reduce the amount of stream bed
disturbance.
To avoid the introduction of suspended solids by
road traffic, the access road should cross as
few tributary streams as possible, and culverts
should not be allowed to flow directly into
streams. Streams should be crossed with small
-9-
I.
log bridges or culverts, whichever would provide
the best protection to streamside vegetation.
A vegetated buffer zone should be left between
all access roads and the streambank.
All areas disturbed during construction activ-
ities should be stabilized to reduce erosion.
Any organic soils excavated during construction
should be stockpiled and spread over disturbed
sites to encourage revegetation.
Waste petroleum and wastewater should be dis-
posed of in an environmentally sound manner and
a plan for safe storage, use, and clean-up of
oil and gas used in project construction and
operation should be prepared following state and
federal oil spill contingency plans (40 CFR
112.38, December 11, 1973).
WILDLIFE
Local residents stated that brown bear, river otter, fox,
and weasel all commonly use the Humpy Creek drainage.
Si tka black-tailed deer are abundant in the Larsen Bay
area. The Humpy Creek drainage supports deer all year, but
because of the generally northerly exposure, it is probably not
a major wintering area (Smith, 1981). The north-south ridge
between Karluk Lake and Uyak Bay from which Humpy Creek drains
is good deer habitat (stratton, 1981). This same ridge is also
an important brown bear denning area (Stratton, R. Smith,
1981).
-10-
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• -• -• -• ..
• •
• -•
• -
•
• -•
•
•
•
• -• -
• ..
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-
, ....
-
-
The following is excerpted from a letter from Roger Smith,
ADF&G Area Managment Biologist, Division of Game:
Brown bear are constant visitors in Larsen Bay
during the summer. They fish for salmon in the lower
reaches of the creek mainly in July and August. Re-
ports received from villagers during the summer of
1980 indicated that 15 or more bears were frequenting
the creek and the village dump. My estimate is that
10-15 bears frequent the hydro project location.
Denning occurs in all the higher mountains in the
Larsen Bay area. Usually dens are located at eleva-
tions above 300-400 feet with a preference for north
facing slopes. The mountain under consideration for
a diversion dam probably is used for denning, but
most dens are probably above 700 feet.
During DOWL field studies, numerous bear trails were ob-
served on the west bluff above the creek, along the creek, and
leading from the bluff down to the stream. The east bluff had
considerably fewer trails.
Eight bald eagle nests have been recorded in the Larsen
Bay drainage (Zwiefelhofer, 1981). Although no nests have been
identified along Humpy Creek, the mouth has been documented as
a feeding area for bald eagles. Rough-legged hawks probably
nest in the upper project area (Zwiefelhofer, 1981).
An unnamed seabird colony containing glaucous-winged
gulls, black-legged kittiwakes and tufted puffin is located on
Amook Island within five miles of the project (ADF&G, 1978b).
A list of mammals found for Kodiak Island Archipelago is
given in Table 3 and a list of birds is given in Table 4.
J. CURRENT UTILIZATION OF WILDLIFE RESOURCES
Roger Smith, Area Management Biologist for the Alaska
Department of Fish & Game, Game Division, on Kodiak Island, had
-11-
TABLE 3
TERRESTRIAL MAMMALS OF THE KODIAK ISLAND ARCHIPELAGO
INDIGENOOS SPECIES
Little Brown Bat
Tundra Vole
Red Fox
Brown Bear
Short-tailed Weasel
Land Otter
INTRODUCED SPECIES
Snowshoe Hare
Arctic Ground Squirrel
Norway Rat
House Mouse
Northern Red Squirrel*
Marten*
Beaver
Muskrat
Roosevelt Elk*
Sitka Black-tailed Deer
Mountain Goat
Dall Sheep
* Introduced to Afognak Island
-12-
SCIENTIFIC NAME
Myotis luncifugus
Microtus oeconomus
Vulpes vulpes
Ursus arctos
Mustela erminea
Lutra canadensis
SCIENTIFIC NAME
Lepus americanus
Citellus parryi
Rattus norvegicus
r1us musculus
Tamiasciurus hudsonicus
Martes americana
Castor canadensis
Ondatra zibethicus
Cervus canadensis
Odocoileus hemionus
Oreamnos americanus
Ovis dalli
• ----
•
-.
• -
• -• •
• -•
• -• .,
•
•
•
• -•
•
•
•
• ...
• -• •
''"¢".
TABLE 4
''M?i
BIRDS OF THE KODIAK ISLAND ARCHIPELAGO -
A -Abundant
~ ... ,.,. S -Spring, March-May
C -Common S -Summer, June-August
U -Uncommon F -Fall, September-November
R -Rare W -Winter, December-February
..... + -Casual
* -Nesting
.....
SPECIES SCIENTIFIC NAME S S F W
Common Loon Gavia immer U U U U
Yellow-billed Loon Gavia adamsii R R U
Arctic Loon Gavia arctic a U U U
Red-throated Loon Gavia stellata U U U U
Red-necked Grebe Podiceps grisegena U + U U
Horned Grebe Podiceps auritus U U U
Short-tailed Albatross Diomedea albatrus + +
Black-footed Albatross Diomedea nigripes C C C
Laysan Albatross Diomedea immutabilis U U U
Northern Fulmar Fulmaris glacialis C C C C
Pink-footed Shearwater Puffinus creatopus +
Flesh-footed Shearwater Puffinus carneipes + +
New Zealand Shearwater Puffinus bulleri + +
Sooty Shearwater Puffinus griseus A A A U
.','1i Short-tailed Shearwater Puffinus tenuirostris A A A U
Manx Shearwater Puffinus puffinus +
Scaled Petrel pterodroma inexpectata U U U
.. ~"I/I
Fort-tailed Storm-petrel Oceanodroma furcata C C C C
Leach's Storm-petrel Oceanodroma leucorhoa U U U
f~
Double-crested Cormorant Phalacrocorax auritus U U U C
Pelagic Cormorant Phalacrocorax pelagicus C C C C
Red-faced Cormorant Phalacrocorax urile C C C U ---
Great Blue Heron Ardea herodias + + + + ---
#~
-13-
..
•
• -
TABLE 4 •
Continued -
• -SPECIES SCIENTIFIC NAME S S F W
• Whistling Swan Olor columbianus C C C R -Canada Goose Branta canadensis U U +
Brant Branta bernicla A + + + •
Emperor Goose Philacte canagica C U C -
White-fronted Goose Anser albifrons U U •
Snow Goose Chen caerulescens + -Mallard Anas platyrhynchos A A A A • Spotbill Duck Anas poecilorhyncha + -Gadwall ~ strepera U U U U
Pintail Anas acuta A C C U • -----
Green-winged Teal C C C U
.. Anas crecca
Blue-winged Teal Anas discors R •
Northern Shoveler Anas clypeata C R R + -European Wigeon Anas penelope U R R • American Wigeon Anas americana C C C U -Canvasback Aythya valisineria + + + • Redhead AXthX a americana + + + .. Ring-necked Duck Aythya collaris R R R
Greater Scaup Ayth;ta marila A C A A •
Lesser Scaup AythXa affinis R R R -
Tufted Duck Axthya americana + + -Common Goldeneye Bacephala clangula C U C C ..
Barrow's Goldeneye Bucephala islandica C U C C • Bufflehead Bucephala albeola C + C C • Oldsquaw Clangula hyemalis A + A A
Harlequin Duck Histrionicus histrionicus A C A A •
Steller's Eider Polysticta stelleri C + U C ..
Common Eider Somarteria mollissima U U U U •
King Eider Somateria spectabilis C R U C -Spectacled Eider Somateria fischeri + • White-winged Scoter Melanitta deglandi A U A A •
-14-• •
TABLE 4
Continued
SPECIES
Greater Yellowlegs
Lesser Yellowlegs
Solitary Sandpiper
Spotted Sandpiper
Wandering Tattler
Ruddy Turnstone
Black Turnstone
Northern Phalarope
Red Phalarope
Common Snipe
Short-billed Dowitcher
Long-billed Dowitcher
Surfbird
Red Knot
Sanderling
Semi-palmated Sandpiper
Western Sandpiper
Least sandpiper
Baird's Sandpiper
Pectoral Sandpiper
Sharp-tailed Sandpiper
Rock Sandpiper
Dunlin
stil t Sandpiper
Buff-breasted Sandpiper
Ruff
Pomarine Jaeger
Parasitic Jaeger
Long-tailed Jaeger
South Polar Skua
Glaucous Gull
TABLE 4
Continued
SCIENTIFIC NAME
Tringa melanoleuca
Tringa flavipes
Tringa solitaria
Actitis macularia
Heteroscelus incanus
Arenaria interpres
Arenaria melanocephala
Phalaropus lobatus
Phalaropus fulicarius
Gallinago gallinago
Limnodromus griseus
Limnodromus scolopaceus
Aphriza virgata
Calidris canutus
Calidris alba
Calidris pusilla
Calidris mauri
Calidris minutilla
Calidris bairdii
Calidris melanotos
Calidris acuminata
Calidris ptilocnemis
Calidris alpina
Micropalama himantopus
Tryngites subruficollis
Philomachus pugnax
Stercorarius pomarinus
Stercorarius parasiticus
Stercorarius longicaudus
Catharacta maccormicki
Larus hyperboreus
-16-
S
C
+
R
C
R
C
C
U
C
C
+
C
+
R
R
A
R
C
C
C
C
U
R
S
C
C
+
u
C
R
C
C
U
C
C
+
u
+
R
A
A
U
U
u
R
+
+
C
C
U
+
+
F
C
C
R
u
R
U
C
U
C
U
R
u
R
U
R
R
C
C
C
U
+
+
C
C
U
R
W
u
R
u
R
+
C
U
R
• ..
• -----..
• -..
• ..
• ..
-• •
•
•
• ---
• ..
• •
• -• -• •
..... SPECIES
Glaucous-winged Gull
.. " Slaty-backed Gull
Herring Gull -Thayer's Gull
Ring-billed Gull
, .... Mew Gull
Bonaparte's Gull
Black-legged Kittiwake
Red-legged Kittiwake
Sabine's Gull
... ,.1/ Arctic Tern
Aleutian Tern
,*,,-,"; Common Murre
Thick-billed Murre
Pigeon Guillemot
Marbled Murrelet
Kittlitz's Murrelet
,0'.1lf Ancient Murrelet
Cassin's Auklet
Parakeet Auklet
Crested Auklet
Least Auklet
Rhinoceros Auklet
Horned Puffin
ml>'"
Tufted Puffin
Morning Dove
'>110.811 Snowy Owl
Hawk Owl
.~.,. Short-eared Owl
Boreal Owl
Belted Kingfisher
_lii:!l
TABLE 4
Continued
SCIENTIFIC NAME
Larus glaucescens
Larus schistisagus ---
Larus argentatus
Larus thayeri
Larus delawarens is
Larus canus
Larus philadelphia
Rissa tridactyla
Rissa brevirostris
Xema sabini
Sterna paradisaea
Sterna aleutica
Uria aalge
Uria lomvia
Cepphus columba
Brachyramphus marmoratus
Brachyramphus brevirostris
Synthliboramphus antiguus
Ptychoramphus aleuticus
Cyclorrhynchus psittacula
Aethia cristatella
Aethia pusilla
Cerorhinca monoccrata
Fratercula corniculata
Lunda cirrhata
Zenaida macrovra
Nyctea scandia
Surnia ulula
Asio flammeus
Aegolius funereus
Megaceryle alcyon
-17-
S S F W
A A A A
+ +
R R R R
R R R
+
C C A A
U U U
A A A U
+ + + +
U U U
C C R
U U
C C A A
R R R R
C C C C
C C C C
R R R R
U U R R
U U U
R R R
+ + C A
+ + + +
R R R R
C C C R
A A A R
+ +
+ +
U U U U
U U U R
C C C C
C C C C
SPECIES
Common Flicker
Yellow-bellied Sapsucker
Hairy Woodpecker
Downy Woodpecker
Northern Three-toed Woodpecker
Eastern Kingbird
Horned Lark
Violet-green Swallow
Tree Swallow
Bank Swallow
Barn Swallow
Cliff Swallow
Black-billed Magpie
Common Raven
Northwestern Crow
Black-capped Chickadee
Red-breasted Nuthatch
Brown Creeper
Dipper
Winter Wren
American Robin
varied Thrush
He:rmit Thrush
Gray-cheeked Thrush
Golden-crowned Kinglet
Ruby-crowned Kinglet
Water Pipit
Bohemian Waxwing
Northern Shrike
starling
Orange-crowned Warbler
TABLE 4
Continued
SCIENTIFIC NAME
Colaptes auratus
Sphyrapicus varius
Picoides villosus
Picoides pubescens
Tyrannus tyrannus
Eremophila alpestris
Tachycineta thalassina
Iridoprocne bicolor
Riparia riparia
Hirundo rustica
Petrochelidon pyrrhonota
Pica pica
Corvus corax
Corvus caurinus
Parus atricapillus
Sitta canadensis
Certhia familiaris
Cinclus mexicanus
Troglodytes troglodytes
TUrdus migratorius
Ixoreus naevius
Catharus guttatus
Catharus minimus
Regulus satrapa
Regulus canendula
Anthus spinoletta
Bombycilla garrulus
Lanius excubitor
Sturnus vulgaris
Vermivora celata
-18-
S S F W
+
+ +
+ +
C C C C
Picoides tridactylus
+
C
C
U
C
C
C
C
U
C
C
C
R
C
A
R
A
C
C
+
C
C
C
A
R
+
C
C
C
C
U
C
C
C
R
C
A
C
A
+
C
C
C
+
R
R
U
C
C
C
C
U
C
C
C
R
C
C
A
+
C
R
C
+
R
C
C
C
C
U
C
C
C
R
U
A
+
+
R
C
+
• •
• .. --
• .. .. -
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-SPECIES
Yellow Warbler -Yellow-rumped Warbler
Blackpoll Warbler -Wilson's Warbler
Red-winged Blackbird
• .,.:16
Rusty Blackbird
Brambling
Pine Grosbeak
.....
Gray-crowned Rosy Finch
Hoary Redpoll
"'."'; Common Redpoll
Pine Siskin
"'*'~# Red Crossbill
White-winged Crossbill
Savannah Sparrow
Dark-eyed Junco
Tree Sparrow
Harris' Sparrow
White-crowned Sparrow
Golden-crowned Sparrow
White-throated Sparrow
Fox Sparrow
Lincoln's Sparrow
Song Sparrow
<>i1l'9111 Lapland Longspur
Snow Bunting
" .. McKay's Bunting
TABLE 4
Continued
SCIENTIFIC NAME
Dendroica petechia
Dendroica coronata
Dendroica striata
Wilsonia pusilla
Agelaius phoeniceus
Euphagus corolinus
Fringilla montifringilla
Pinicola enucleator
Leucosticte tephrocotis
Carduelis hornemanni
Carduelis flammea
Carduelis pinus
Loxia curvirostra
Loxia leucoptera ---
Passerculus sandwhichensis
Junco hyemalis
Spizella arborea
Zonotrichia querula
Zonotrichia levcoEhrys
zonotrichia atricapilla
zonotrichia albicollis
Passerella iliaca
Melospiza albicollis
Melospiza melodia
Calcarius lapponicus
Plectrophenax nivalis
Plectrophenax hyperboreus
-19-
S S F W
R C R
R U R
+
U A U
+
R R R
+
C C C C
U U U U
+
C C C C
C C C C
R R R R
C C C C
A A A +
R + U U
U U U
+ + +
R + R R
A A C R
+
A A C R
+ +
C C C C
A A C +
C C C C
+
the following comments (personal communication, 1981). Most of
the local hunting effort does not occur near the proposed proj-
ect site. Hunters generally use skiffs to hunt across Larsen
Bay and Uyak Bay. Some hunters from Kodiak and other Alaskan
loca tions al so hunt from Larsen Bay. Because Larsen Bay is
incl uded in a much larger area for harvest compilations, no
exact figures are available. Based on local estimates, an
annual harvest of 50 deer occurs in the Larsen Bay drainage,
and at least another 50 to 100 deer are probably taken by local
residents from Uyak, Zachar and Spiridon Bays.
Both red fox and land otter are hunted and trapped near
Larsen Bay, but most of the trapping occurs in Uyak Bay.
Occasionally locals trap, but most of the harvest is taken by
Kodiak residents. Larsen Bay falls within two river otter har-
vest areas. The village is included with Karluk Lake, where 35
otters were reported in 1981. Sixty-five otters were taken
from Zachar Bay to the south side of the entrance of Larsen
Bay. The take of otters only from Larsen Bay drainages prob-
ably is less than 15 otters per year.
K. ENDANGERED SPECIES
No endangered species or subspecies are known to occur on
Kodiak Island (Money, 1981). Peales peregrine falcon, the non-
endangered subspecies, does nest on Kodiak Island. Both endan-
gered subspecies of peregrine falcon have been reported to
winter on Kodiak Island, but this has not been verified.
Peregrine falcons were trapped and observed by U. S. Fish and
~Vildlife Service biologists during the winter of 1980-81, but
they were all the nonendangered subspecies (Amaral, 1982).
L. WILDLIFE IMPACTS
Project construction will result in permanent habitat loss
in the dam site vicinity, powerhouse location, and along the
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access route to the dam site. Due to the small size of the
project, this loss is expected to be minimal. Temporary habi-
tat alteration will occur at equipment staging areas, the camp
si te, and in the transmission 1 ine right-of-way. Few adverse
impacts are anticipated from gravel removal for project con-
struction because an existing borrow site will be used.
Operation of heavy equipment and other construction activ-
ities will create considerable noise and may also result in
disturbance of wildlife and temporary abandonment of tradi-
tionally used areas. Since all construction activity should
occur within a six-month period and the project area is close
to town, project construction should not have a major impact •
During project operation, alternations in the flow regime
between the diversion weir and the powerhouse may force water-
dependent animal s such as the water ouzel to relocate. Some
minor mortality to birds may result from colI is ions with the
transmission line.
A major potential impact from construction of a hydropower
facility would be disturbance to wildlife if the route to the
diversion dam allowed access above the alder zone. The use of
three-wheeled vehicles and snowmachines is a popular sport in
Larsen Bay. Once above the alder zone, these recreational
vehicles could probably be taken the entire length of the ridge
between Karluk Lake and Uyak Bay.
This area is good deer habitat and an important denning
area for brown bear. Both Roger Smith, Game Biologist with the
Alaska Department of Fish and Game, and Bob Stratton, Refuge
Manager for Kodiak National wildlife Refuge, felt that the use
of recreational vehicles on this ridge would create serious
disturbances to wildlife which could result in the desertion of
-21-
dens by bears and foxes and might al ter the distribution or
movements of deer and other animals.
Current plans have the road terminating in a very narrow
portion of the Humpy Creek drainage where it appears that ex-
tension of the road would require blasting and tree removal.
M. WILDLIFE MITIGATION
The proposed project is on such a small scale that most
impacts such as disturbance of wildlife during construction
will be minor and short term. To further minimize impacts, the
following guidelines should be followed:
If an on-site construction camp is required, all
structures and equipment should be removed upon con-
struction completion. The ground should be graded to
its original contours and revegetated with natural
vegetation.
The material site should be operated in accordance
with OSHA and the Mine Safety and Health Administra-
tion standards.
the side slopes
stable condition
When gravel extraction is complexed,
should be returned to a long term
(3: 1 or greater). Care should be
taken to insure proper drainage at all times.
No feeding of wildlife should occur. All refuse should be
placed in metal containers with heavy lids, incinerated on site
on a regular basis, and the nonburnable remains removed to an
existing landfill.
If problems \vi th bears or other wildlife do arise, the
appropriate Alaska Department of Fish & Game officials should
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be contacted and handling of the problem should follow their
recommendations.
Hunting or fishing in the project area should not be per-
mitted by the contractor or construction workers during con-
struction.
A minimum 330-foot buffer of no construction activity
should be established around active eagle nests and where pos-
sible a seperation of 500 feet should be maintained. In addi-
tion, the Alaska Department of Fish and Game strongly dis-
courages siting of construction camps, material sites, and
other high activity areas within one-quarter mile of an active
eagle nest. Restrictions may include prohibiting fixed-wing
aircraft from coming within a radius of 500 feet, and heli-
copters from coming within a radius of 1,500 feet of the air-
space surrounding active nests.
The transmission line should be designed to minimize large
raptor electrocution.
Use of the project road by any vehicle other than main-
tenance vehicles should be prohibited.
N. VEGETATION
Birch is the dominant tree throughout most of the Humpy
Creek drainage except in outwash plains where it is replaced by
cottonwood. The understory varies with the density of canopy
cover, with the following species predominant: elderberry,
highbush cranberry, rose, lady and fiddlehead fern, and scat-
tered alder and willow •
-23-
O. ARCHAEOLOGIC AND HISTORIC SITES
An archaeologic site has been identified at the mouth of
Humpy Creek, and numerous sites are known to exist throughout
Larsen Bay and the surrounding region (Dilliplane, 1981). The
Division of Parks has recommended that an archaeological survey
be done in this area before project construction begins.
P. POTENTIAL VISUAL IMPACTS
The transmission line is the only component of this proj-
ect which may be visible from town. An existing road will
provide access to the powerhouse, which should be screened from
view by the surrounding vegetation. The diversion weir, pen-
stock and route to the diversion weir should be concealed from
view from the town by the narrow, meandering stream cut.
Q. IMPACT ON RECREATIONAL VALUES
Project construction and operation should have little
effect on recreational values. The route to the diversion weir
may provide additional area for the use of three-wheeled
vehicles.
R. AIR QUALITY
During project construction, exhaust fumes from diesel
equipment and dust generated by construction activity may im-
pact air quality. Dispersion of air pollutants is expected to
be adequate to prevent any significant impacts to air quality
in the area.
Electrical power for Larsen Bay is currently provided by
diesel generators. Particulate emissions from the combustion
of diesel fuel have a high proportion of particles with a very
-24-
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small size fraction. These smaller particles penetrate deeper
into the lungs and are therefore more hazardous to health than
emissions from the combustion of other hydrocarbon products.
Replacement of the diesel generating facilities by hydro-
electric power should lower the discharge of hydrocarbon pollu-
tants.
S. SOCIOECONOMIC IMPACTS
The construction force in Larsen Bay is not expected to
exceed 25 people, and it will average less than 20. If accom-
modations are not available locally, trailers would be brought
in and a work camp set up. Mobilization would begin about
April 1, with actual work beginning about April 15. The proj-
ect shoul.d be completed by September 31 of the same year.
Working hours would be 10 hours a day, six or seven days a week
until project completion.
The presence of 15 to 25 strangers in Larsen Bay for an
extended period of time is bound to disrupt the traditional
I ife style of the village. Skilled craft labor will be re-
quired. Al though local hire will be considered, local resi-
dents will not be hired unless they have appropriate skills.
However, the Kodiak Area Native Association has expressed a
willingness to provide training to local people so that they
will be hired for this project. With the I imi ted employment
opportunities available in Larsen Bay, local residents may re-
sent any importation of laborers. However, construction will
occur during the summer months, so residents may be busy with
commercial fishing and not be available for hire.
The potential does exist for confl icts with local resi-
dents over alcohol use because alcohol is generally present in
construction camps. Although Larsen Bay is not dry, there are
-25-
no liquor outlets in town. This proximity of alcohol may lead
to the acquisition of alcohol by local residents through pur-
chase or barter.
Archaeological artifacts can easily be found in various
parts of Larsen Bay, including the township. Therefore the
potential exists for the unauthorized removal of the items by
construction personnel.
The availability of hydropower may provide economic bene-
fits to the village and individual families. Cheaper electric
bills should benefit for the householders. However, once
centralized power is available, household generators will be
outmoded and a local resale market will probably not exist.
Residents may elect to switch from oil or wood heat to electric
heat, which will require a large initial cash output for con-
version. Maintenance of the power generation equipment will
provide periodic employment for a skilled resident.
T. LAND STATUS
The diversion weir to be constructed across Humpy Creek,
the borrow site location near the diversion weir, and a portion
of the proposed trail from the diversion weir to the powerhouse
are within lands for which the surface estate has been interim
conveyed to Koniag, Incorporated, as part of their entitlements
under the Alaska Native Claims Settlement Act of 1971 (ANCSA),
Public Law 92-203. Interim conveyance is used in this case to
convey unsurveyed lands. Patent will follow interim conveyance
once the lands are identified by survey.
The powerhouse, and an alternative borrow site near the
city solid waste disposal area, are located on lands which are
interim conveyed or patented for surface and subsurface estates
to the City of Larsen Bay. The proposed transmission route
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al ternatives from the powerhouse to Larsen Bay traverse both
patented private, City of Larsen Bay, Townsite Trustee and
patented Koniag Corporation property. An airport lease, Serial
Number AA 9087, is near the powerhouse and the final transmis-
sion route alternative should take this into account •
Larsen Bay has a federal townsite, U.S.S. 4872, with the
patent issued to the Bureau of Land Management Townsite Trust-
ee. The Trustee has deeded occupied parcels to the residents
and some vacant lots to the city. Other subdivided property
remains with the Trustee. A permit would be required for the
transmission line to cross Trustee lands and it may be issued
by the u.s. Department of Interior after an affirmative resolu-
tion by the city council.
All of the interim conveyed lands identified above are
also part of the Kodiak National Wildlife Refuge as classified
and withdrawn by Public Land Orders 1634, 5183 and 5184. All
lands that were part of a National Wildlife Refuge before the
passage of ANCSA and have since been selected and conveyed to a
Native corporation will remain subject to the laws and regula-
tions governing the use and development of such refuges as out-
lined in Section 22(g) of P.L. 92.203.
U. PERMITTING REQUIREMENTS
The following permits may be required for construction of
the Larsen Bay hydropower project:
Under the authority of Section 404 of the Fed-
eral Water Pollution Control Act Amendments of
1972, the Army Corps of Engineers (COE) must
authorize the discharge of dredged or fill mate-
rials into navigable waters, which includes ad-
jacent wetlands, by all individuals, organiza-
-27-
tions, commercial enterprises, and federal,
state and local agencies. A COE Section 404
Permit will therefore be required for the diver-
sion weir on Humpy Creek.
A water Qual i ty Certificate from the State of
Alaska, Department of Environmental Conservation
(DEC), is also required for any activity which
may result in a discharge into the navigable
waters of Alaska. Application for the certifi-
cate is made by submitting to DEC a letter re-
questing the certificate, accompanied by a copy
of the permit application being submitted to the
Corps of Engineers.
The Alaska Department of Fish and Game, Habitat
Division, under authority of AS16. 05. 870, the
Anadromous Fish Act, requires a Habitat Protec-
tion Permit if a person or governmental agency
desires to construct a hydraulic project or
affect the natural flow or bed of a specified
anadromous river, lake, or stream, or use equip-
ment in such waters. A Habitat Protection Per-
mit will be required for the diversion weir, and
instream or streambank work on Humpy Creek.
Under authority of AS16.05.840, the Alaska
Department of Fish and Game can require, if the
Commissioner feels it necessary, that every dam
or other obstruction built by any person across
a stream frequented by salmon or other fish be
provided with a durable and efficient fishway
and a device for efficient passage of fish. A
Habitat Protection Permit will therefore be
required.
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All public or private entities (except federal
agencies) proposing to construct or operate a
hydroelectric power project must have a license
from the Federal Energy Regulatory Commission
(FERC) if the proposed site is located on a
navigable stream, or on U. S. lands, or if the
project affects a u.s. government dam or inter-
state commerce •
A Permit to Construct or Modify a Dam is re-
quired from the Forest, Land, and Water Manage-
ment Division of the Alaska Department of Nat-
ural Resources for the construction, enlarge-
ment, alteration, or repair of any dam in the
State of Alaska that is ten feet or more in
height or stores 50 acre-feet or more of water.
Since the weir is less than 10 feet high and has
only minimal storage, this permit is not likely
to be required.
A Water Rights Permit is required from the
Director of the Division of Forest, Land and
Water Management, Alaska Department of Natural
Resources for any person who desires to appro-
priate waters of the State of Alaska. However,
this does not secure rights to the water. When
the permit holder has commenced to use the ap-
propriated water, he may then notify the direc-
tor who will issue a Certificate of Appropria-
tion. The Certificate secures the holders'
rights to the water .
The proposed project area is located within the
coastal zone. Under the Alaska Coastal Manage-
ment Act of 1977, a determination of consistency
-29-
with Alaska Coastal Management Standards must be
obtained form the Division of Policy Development
and Planning in the Office of the Governor.
This determination would be made during the COE
404 permit review.
Any party wishing to use land or facil i ties of
any National Wildlife Refuge for purposes other
than those designated by the manager in charge
and published in the Federal Register must ob-
tain a Special Use Permit from the U. S. Fish &
wildlife Service. This permit may authorize
such activities as rights-of-ways; easements for
pipelines, roads, utilities, structures, re-
search projects; entry for geologic reconnais-
sance or similar projects, filming and so forth.
Note that all lands that were part of a National
Wildlife Refuge before the passing of the Alaska
Native Claims Settlement Act, and have since
been selected and conveyed to a Native corpora-
tion as part of their entitlement under ANCSA,
will under remain under the rules and regula-
tions of the refuge.
v. RECOMMENDATIONS
Although full-scale environmental field studies were not under-
taken, the small scale of the project and the lack of major
fishery or wildlife resources in the affected area indicate
that these studies were considered sufficient to assess poten-
tial impacts to the area. Therefore, unless substantial addi-
tional concerns are expressed by local residents or regulatory
-30-
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agencies, no additional environmental studies are considered
necessary •
W. REFERENCES CITED
Alaska Department of Fish & Game, 1978a, Alaska's Fisheries
Atlas, Volumes I and II.
Alaska Department of Fish & Game, 1978b, Alaska's Wildlife and
Habitat, volume II.
x. PERSONAL COMMUNICATIONS
Amaral, Michael. Wildlife Biologist, U. S. Fish and Wildlife
Service, Endangered Species. 1982.
Dilliplane, Ty. Alaska Department of Natural Resources, Divi-
sion of Parks. 1981.
Manthey, Ken. Fisheries Biologist, Commercial Fisheries Divi-
sion, Alaska Department of Fish and Game, Kodiak, Alaska.
1981.
Money, Dennis. Wildlife Biologist, U.S. Fish and wildlife Ser-
vice, Endangered Species. 1981.
Smith, Roger. Game Biologist, Game Division ADF&G, Kodiak,
Alaska. 1981.
Stratton, Bob. USFWS, Refuge Manager, Kodiak National Wildlife
Refuge. 1981.
Zwiefelhofer, Denny. u. S. Fish and Wildlife Service, Kodiak
National Wildlife Refuge. 1981.
-31-
LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX F
LETTERS AND MINUTES
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Public Meeting Questions and Answers
A public meeting was held on March 26, 1982 in the community
of Larsen Bay to discuss the results of this study. The
following questions were asked and answers given during the
meeting.
1. When would the project be built?
construction could begin in the summer of 1984 •
2. What would the per kilowatt cost be?
That type of financial analysis was not done.
3. How would the payback for the cost of the dam work?
4.
5.
It is difficult to say at this point, however, the
State is currently giving the money out as grants.
Would generators be installed as a back-up?
Yes.
Hydroelectric power has brought high costs to the town
of Kodiak -will it be the same for Larsen Bay?
We would expect not because this is a much smaller
project. However, the method of charging for power has
not been determined and this study was not intended to
evaluate charges to consumers •
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE -ANCHORAGE, ALASKA 99501
-~1r. Bob ~1artin
Regional Supervisor
State of Alaska
Department of Environmental Conservation
437 E Street
Second Floor
Anchorage, Alaska 99501
July 28, 1982
Phone: (907) 277-7641
(907) 276-0001
Subject: Draft Feasibility Reports on Hydroelectric Projects at
King Cove, Old Harbor, Larsen Bay; Draft Reconnaissance
Report of a Hydroelectric Project at Togiak .
Dear Mr. Martin:
Thank you for your March 26, 1982, letter to Mr. Don Baxter of my
staff regarding the above referenced reports. We appreciate your
participation and timely input in reviewing the draft reports and are
pleased to hear that you find no apparent major or permanent
environmental impacts related to the projects, with the exception of
Togiak.
The project at Togiak appears to be marginally feasible from an
economic standpoint and the likelihood of proceeding with additional
studies is questionable. However, if the project is carried forward,
appropriate mitigation measures will be taken to preserve Quigmy River
water quality. An instream flow study program would become an integral
part of any additional study programs.
Thank you again for your consideration and timely input. Should
you have further questions regarding these projects, please contact
myself or Mr. Don Baxter of my staff.
c\? J.\
Eric P. Yould '-\
Executive Director
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE -ANCHORAGE, ALASKA 99501
r~s. Judy Ma rquez
Director
State of Alaska
Department of Natural Resources
Division of Parks
619 Warehouse Drive, Suite 210
Anchorage, AK 99501
July 28, 1982
Phone: (907) 277-7641
(907) 276-0001
SUBJECT: Draft Feasibility Reports on Hydroelectric Projects at
King Cove, Old Harbor, Larsen Bay; Draft Reconnaissance Report
of a Hydroelectric Project at Togiak.
Dear Ms. Marquez:
Thank you for your letters of April 12, March 30 and March 31,
1982, to Ms. Laurel Bennett of DOWL Engineers regarding the above
referenced feasibility and reconnaissance reports. We appreciate your
participation and timely input in reviewing the draft reports .
In response to the concerns voiced in your letters,
preconstruction cultural resource surveys would be accomplished prior to
the initiation of construction activity on any of the projects. Any
work associated with the scoping and implementation of such surveys
would be fully coordinated with your office. Furthermore, the project
at Togiak does not appear to be attractive at this point in time due to
economics, and it is doubtful that it will be carried forward into
developmental stages.
Should you have further questions regarding these studies, please
contact myself or Mr. Don Baxter of my staff.
Sincerely,
~-;.y~~Jl
Executive Director
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• Letter
March 31, 1982
Page 2
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Page IX-8, fourth and fifth paragraphs: Please note that the KIHA
will be informed of the project's availability of electricity to
prdvide space heating. The plans for the new housing units could
incorporate a combination of electrical and fuel heating appliances.
Appendix E, page 24, third paragraph: K~NA will do everything in its
pO\,/er to provide training to local people in order for the selected
contractor to hire. KANA strongly urges the APA to provide the quali-
fications necessary to construct the project, encourage contractors
to hire locally, and to oversee that minimum social impacts occur •
KANA feels that the APA has the responsibility to insure total involve-
ment of the local community that is affected by project develo[1fllent.
In final comments to the project for Larsen Bay, it should be pointed out to
your Review Board that the BIC ratio is somewhat misleading based on the
assumption of the comparable costs bet\-Jeen hydroelectric and a hypothetical cen-
tralized diesel pm'/ered electrica1 distribution system. KANA does question the
,pay-back method to be used if the project is approved. Even though that method
has not been resolved, the recent eaonomic condition prevailing in Larsen Bay
may put the commlJnity in jeopardy from v/hatever pay-back scheme is condoned by
the State. KAriA urges tile Revi e\'I Board to keep tha tin rni nd.
~ne more thing concerning Larsen Bay is the question of AP/\'s responsibility to
develop a local utilit~ to handle the project's services. the KIHA is also the
regional electrical authority and could act as the'utility if the Larsen Bay
community could not develop one. Please keep this in mind as v/ell.
The following comments relate to Old Harbor's Feasibility Study:
Page 11-1, first paragraph: Correction. The ~ower plant is owned
by AVEC and the city operates it through contract. KANA is dismayed
that this information because Dowl Engineering had collected the correct
information during their development of Old Harbor's Community Profile
which Dm4L had contracted \'Iith the State. This unnecessary error ;s a
derogatory example of Dowl's experience and reputation as a rural oriented
consultant firm.
Page VII-2, second paragraph: The KIHA has submitted a request for funds to
construct seventeen (17) single family units in Old Harbor. HUD is the
grant agency but the KIHA actually does the development.
" .
Page IX-7, second paragraph: Another example of Dowl 's demonstrative inability
to keep things correct. What cannery -there is none,will electrical
demand be used to replace industrial 0eneration?
Page X-5, last pJragraph: KA~lA maintains the same pbsture on dcveloplllcnt
of skills for 10Clll peoplc .)nd encou)·.)(Jcment of local hire as explained
in the Larsen Gay conilllents. KJ\NA docs not shilre the assumption that 111,:)oY
residents Me lHely to be busy \vith commercial fishing. The fisheries
economy is such that a project development such .)s tile hydroelectric \lOuld
dril\,l interest from the local labor force to talc part in.
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE· ANCHORAGE, ALASKA 99501
Ms. lone M. Norton
President
Kodiak Area Native Association
P.O. Box 172
Kodiak, Alaska 99615
July 28, 1982
Phone: (907) 277·7641
(907) 276·0001
SUBJECT: Draft Feasibility Reports on Hydroelectric Projects at
Larsen Bay and Old Harbor.
Dear Ms. Norton:
The following letter addresses issues or answers questions
contained in Mr. Tom Peterson's letter of March 13, 1982, regarding the
draft reports referenced above. We appreciate you and your staffs'
participation and timely input in reviewing the reports. Our
responses to your comments relating to the projects are included below.
Larsen Bay Hydroelectric Project:
Page II-3
The text has been modified to incorporate this change. It has
also been brought to our attention that the cannery has been
purchased by an outside entity and is in the process of being
reopened .
Page VII-3
The text has been modified to incorporate this change. The
application for funding does not affect our consumption estimates.
Page VII-9
The text has been modified to incorporate this change.
Page IX-8
The text has been modified to incorporate this change.
Appendix E, page 24
If a decision is made to proceed with construction of the
Larsen Bay Hydroelectric Project, attempts will be made by the
Power Authority to provide local information on the
qualifications necessary for construction and operation and
maintenance of the facility, to encourage local hire, and to see
that social impacts are minimized.
Your final comments regarding the economic analysis, method of
pay-back, and selection of a local utility to operate the project
a re noted.
Old Harbor Hydroelectric Project:
Page II-I
We have made the necessary correction.
Page VII-2
The text has been modified to incorporate this change.
Page IX-7
The text has been changed to more fully explain the cannery
issue. Cannery boats frequently dock at Old Harbor and maintain
operations for many weeks. These boats usually request power from
the city, according to Mayor Haakanson.
Page X-5; Appendix E, page 24
We fully support local hire and we did not simply assume that
many residents would be busy fishing. This information came to
light in a public meeting with the community and during interviews
with the Tribal Council President. Our comments regarding Appendix
E, page 24, of the .Larsen Bay Report apply here as well.
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• --Again, your comments are noted on the economic analysis and on -
the ability of the community to pay back any loans used for project
development. ..
Thank you again for your comments and timely input. Should you
have further questions regarding these projects, please contact myself
or Mr. Don Baxter of my staff.
(e~e:? . .vM
Eric P. Yould '-\
Executive Director
cc: Frank Carlson, Mayor, Larsen Bay
Frank R. Peterson, President, Larsen Bay Tribal Council
Sven Haakanson, Mayor, Old Harbor
Walter Erickson, President, Old Harbor Tribal Council
Marlin Knight, Executive Director, KIHA
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ALASKA POWER AUTHORITY • •
334 WEST 5th AVENUE· ANCHORAGE, ALASKA 99501 Phone: (907) 277-7641
(907) 276-0001 •
The Honorable Frank M. Carlson
Mayor
. City of Larsen Bay
Post Office Box 8
Larsen Bay, Alaska 99624
August 3, 1982
Subject: Larsen Bay Hydroelectric Project, Draft Feasibility Report.
Dear Mayor.Carlson:
Thank you for your letter of April 1, 1982 to Mr. Don Baxter of my
staff regarding the above referenced report. The Power Authority is
well aware of the rapidly escalating costs of electric energy in rural
Alaska and of the benefits to the City of Larsen Bay if the
hydroelectric project is developed. We will be making a decision on
whether or not to proceed with final design of the Larsen Bay Project in
the near future. We will notify you of the results of that decision
once it is made.
Thank you for your interest in the Larsen Bay Hydroelectric
Project. Should you have any questions regarding the project, please
contact myself or Mr. Baxter.
Sincerely,
S;~YO?' ~ ~
Executive Director
cc: Senator Bob Mulcahy
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE -ANCHORAGE, ALASKA 99501 Phone: (907) 277-7641
(907) 276-0001
July 28, 1982
-Mr. Jack W. Sedwick
Director
State of Alaska
Dept. of Natural Resources
Division of Forest, Land and Water
Management
555 Cordova Street
Pouch 7-005
Anchorage, AK 99501
SUBJECT: Draft Feasibility Reports on Hydroelectric Projects
at King Cove, Larsen Bay and Old Harbor; Draft Reconnaissance
Report of a Hydroelectric Project at Togiak.
Dear Mr. Sedwick:
Thank you for your letter of April 12th regarding the above
referenced reports. The following letter addresses issues and answers
questions contained in your letter. We appreciate the participation and
timely input of you and your staff in reviewing the draft reports.
Our responses to your comments are included below:
a. Permit to Construct or Modify a Dam
For King Cove, Old Harbor and Larsen Bay, plans will
be submitted during the design phase of these projects,
however, we understand that a permit will not be
required because the proposed dams are less than 10 feet
in height. The dam proposed for the Togiak site is
greater than 10 feet in height, but the project does
not appear to be economically attractive. It is therefore
doubtful that the project would ever be developed.
b. Water Rights Permit
Except for the Quigmy River near Togiak, there are no
established navigable uses for any of the streams or rivers
under consideration. The text has been modified to reflect
this comment.
In a meeting with Paul Janke, some concern was expressed about
mlnlmum flows. This issue is addressed in our letters to the
u.S. Fish & Wildlife Service (USFWS), copies of which are attached.
Mr. Jack W. Sedwick
July 28, 1982
Page 2
Discussions of impacts during operations and maintenance, water
quality issues, and loss of alternative uses have been incorporated into
the final report text. Furthermore, ADEC concerns regarding fish and
game resources have also been addressed in the final report text and in
the attached letters to USFWS.
Thank you again for your consideration and timely input. The
Power Authority looks forward to a successful working relationship with
the Department of Natural Resources in bringing these projects forward.
Should you have further questions, please contact myself or
~1r. Don Baxter of my staff.
~~.~J)
Executive Director
Attachments as noted
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~~ KODIAK ISLAND BOROUGH
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April 12, 1982
Mr. Eric P. You1d
Executive Director
Alaska Power Authority
334 West 5th Avenue
Anchorage, Alaska
99501
Telephones 486-5736 -486-5737 -Box 1246
KODIAK, ALASKA 99615
RE(;cIVt:O
I'.?R 1 ~ 1982 \
AlAS'I.A PO'rVER '·.UTI!ORITY
RE: Feasibility Studies of Hydroelectric Projects in Old
Harbor and Larsen Bay
Dear Mr. Yould:
Thank you for the opportunity to review the draft feasibility
studies of hydroelectric projects in Old Harbor and Larsen
Bay.
The reports appear to be comprehensive and well-prepared. I
have two general co~ments to make regarding these studies.
First, I expect the findings of these studies to be directly
incorporated into the "electrification" study the APA is spon-
soring in the Kodiak Island Borough. Secondly, I hope that
the APA Board of Directors acts on these projects by promoting
hydroelectric development in both Old Harbor and Larsen Bay.
Thanks again for the opportunity to comment on this project.
Sincerely,
~~
LindCl Freed
CZ~1 Coordina tor
Comnunity Development
Department
cc. Frank Carlson, Mayor Larsen Bay
Sven Haak.:.1l1son, H.:1yor Old H.:lrbor
LF/jda
ALASKA POWER AUTHORITY
334 WEST 5th AVENUE· ANCHORAGE, ALASKA 99501
Ms. Linda Freed
.CZM Coordinator
Community Development Department
Kodiak Island Borough
Box 1246
Kodiak, AK 99615
July 28, 1982
Phone: (907) 277·7641
(907) 276·0001
SUBJECT: Draft Feasibility Reports on Hydroelectric Projects at
Old Harbor and Larsen Bay.
Dear Ms. Freed:
Thank you for your April 12th letter regarding the above referenced
reports. We appreciate your participation and timely input in reviewing
the draft reports.
The findings of these reports will be incorporated into the
"electrificationll study we are sponsoring for the Kodiak Island Borough.
Remy Williams of my staff will be managing that particular study.
Furthermore, we also share your interest in wanting to bring these
projects forward and hope that they receive a favorable response from
our board of directors.
Thank you again for your consideration and timely input. Should
you have further questions regarding these projects, please contact
myself or t"r. Don Baxter of my staff.
Sincerely,
~;. yo? "\ ~
Executive Director
cc: Frank Carlson, Mayor Larsen Bay
Sven Haakanson, Mayor Old Harbor
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United States Department of the Interior
IN REPLY REFER TO:
WAES
Eric P. Yould
Executive Director
Alaska Power Authority
334 W. 5th Avenue
Anchorage, Alaska 99501
Attn: Don Baxter
Dear Mr. Yould:
FISH AND WILDLIFE SER VICE
1011 E. TUDOR RD.
ANCHORAGE, ALASKA 99503
(907) 276-3800
RE.CE\\JEO
r ·-n 1 6 \~t'2
I \. ~.
He: Larsen Bay Hydroelectric Project
Feasibility Study
The u.S. Fish and Wildlife Service (FWS) has reviewed the above referenced
draft report submitted by DOWL Engineers. It is our intent in the following
comments and recommendations to: 1) provide information which will enable
you to avoid or minimize fish and wildlife losses associated with the
project; 2) identify information needs which are necessary for objective
project planning and decision-making; and 3) to identify those concerns
which, if adequately addressed, would make the project acceptable to us, and
determine our response to anticipated Federal permits and/or licenses
associated with this project.
General comments:
In general, we find the conclusion of project feasibility based almost
entirely on economic and engineering information.
We feel the credibility of this conclusion could be greatly enhanced by
comprehensively addressing the following issues:
1) Significantly expanding your data base regarding fish use
(populations) and habitat.
2) The identification and incorporation of appropriate mitigation
measures (clearly developed from the data base in #1).
3) Diversifying the types and scope of alternative electrical power
production systems •
Specific comments:
Section I, page 5 --
Section X, page 1 --
Section X, page 3 --
Section X, page 4 --
Summary comments:
The net cost figure of $4.9 million dollars does not
include costs of additional environmental studies and
mitigation measures.
As mitigation, fish passage structures may be needed
for the existing diversion dam as well as the project
dam.
Dolly Varden are char. Additional fisheries studies
will be needed to ascertain the numbers of fish using
the stream, and whether there is useable fish habitat
above the existing dam. The possible upper limit of
pink salmon spawning should be delineated. Spill
projections between the dam and the tailrace should
be made.
Bear denning sites should be mapped and impacts of
the project on year-round bear use should be
discussed in detail. Habitat mapping should be done
for Sitka black-tailed deer and eagles, too.
According to the Fish and Wildlife Service mitigation policy, the fish and
wildlife in the Larsen Bay vicinity fall into Resource Category 3, which
means habitats are of high to medium value to the species there, and habitats
are abundant. The corresponding mitigation planning goal for Resource
Category 3 is no net loss of habitat value, while minimizing the loss of
in-kind habitat value. Our future actions regarding various Federal permit
and license applications will be to ensure that fish and wildlife resources
in the project area are adequately described, that all significant impacts to
those resources are identified, and that all adverse impacts are mitigated to
reach our goal of no net loss.
We look forward to continuing working with the Alaska Power Authority and
providing technical assistance in the planning stages of this project. Thank
you for the opportunity to comment on the report.
' .. ]:M/;,1.N ~ Regional Director
cc: FWS-ROES, WAES
ADF&G, NMFS, ADEC, OCM, Juneau
ADF&G, NMFS, ADEC, EPA, Anchorage
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE -ANCHORAGE, ALASKA 99501
Mr. Keith Schreiner
Regional Director
U.S. Fish & Wildlife Service
1011 E. Tudor Road
Anchorage, Alaska 99503
July 30, 1982
Phone: (907) 277-7641
(907) 276-0001
Subject: Draft Feasibility Reports on Hydroelectric Projects at
King Cove, Old Harbor, Larsen Bay; Draft Reconnaissance
Report of a Hydroelectric Project at Togiak.
Dear Mr. Schreiner:
This letter has been prepared in response to Mr. Gerald Reid's
letters of April 14 and April 15, 1982, regarding the above referenced
projects. We appreciate your timely input and your staff's
participation in several agency meetings relating to these projects.
GENERAL COMMENTS:
At our request, DOWL Engineers (DOWL) has carefully reviewed the
letters and has responded to your comments, many of which were quite
constructive. However, the general comments and closing paragraphs of
the letters appear to be in a format and of a nature that sets a
generalized U.S. Fish and Wildlife Service (USFWS) policy for all
hydroelectric projects, does not take into account the presence of
existing data or local knowledge that is site specific, and assumes that
all hydroelectric projects cause or have the potential to cause similar
losses in fish and wildlife resources, habitat or both. It should also
be noted that personal contact was made with refuge personnel and staff
members of your Ecological Services several times over the course of the
studies and that in addition to these contacts, two formal agency
meetings were held to consider the implications of the projects. The
draft reports were not prepared without the input of knowledgeable field
personnel from both USFWS and the Alaska Department of Fish & Game
(ADF&G). Additionally, the nature and size of the projects must be
considered in any such evaluation, as well as consideration of the site
specific determinants.
Further, DOWL met on April 28, 1982, with representatives from your
office and ADF&G to discuss the project on a site specific basis. In
part, the specific comments provided below reflect the results of that
meeting.
Keith Schreiner
July 28, 1982
Page 2
SPECIFIC COMMENTS:
King Cove:
Section I, Page 5. Based on other comments provided below, the possible
cost of additional studies and mitigation measures is considered minor.
The space heating credit is taken only for the dollar value of the
heating oil being displaced. Deductions from this credit were taken as
you have indicated they should have been.
Section 1, page 6. Several additional field trips are planned to
confirm the comment noted under Appendix E, page 5.
Section IV, page 1. The hydrological data you noted is currently being
collected. Preliminary winter streamflow data collected on Delta Creek
appear to indicate that the measured flows utilized for energy
generation are consistent with the estimates in the hydropower
feasibility report. This conclusion is based on limited periodic
discharge measurements, which will be used to develop rating curves for
this creek as part of a one-year long stream gaging effort. Continuous
streamflow data are being collected and will be made available as soon
as the field study is completed. The range of estimated winter flows
(December through April) utilized for energy generation and the observed
flows are as follows:
Estimated flow range: 8.8 to 14.5 cfs
Observed flow range: 16 to 20 cfs
It should be noted that that range of observed flows may change slightly
as stream stage records are analyzed on the basis of completed rating
curves. Spillage and projected discharges will be a function of final
design.
Section VI, page 12. This will be accomplished following the collection
of the one year of actual discharge data.
Section VI, rage 16. Schedules for cleaning and alternative methods of
disposal wil be considered during final design and in determining
operational procedures. The expected decrease in turbidity and sediment
loads will in general enhance downstream conditions.
Section VII, sage 4. The demand analysis presented has been
standardizedy ApA for comparison of all hydroelectric projects and is
thought to be realistic. The Power Authority's purview does not extend
to denying rural Alaskans an improvement in their standard of living
through the availability of reliable, stable-priced power.
Appendix E, pale 5. Surveys of Delta Creek have been taken on a yearly
basis for the ast 21 years by experienced ADF&G observers. Surveys are
flown close to the normal time of peak spawning, so as to obtain maximum
escapement counts.
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July 28, 1982
Page 3
The fisheries resources and upward extent of salmon spawning in
Delta Creek were discussed with Arnie Shawl, the ADF&G fisheries
biologist in Cold Bay, on three occasions and with several long time
local residents. All were in agreement that pink salmon in the project
area spawn in a tributary below the airport, and that chum salmon rarely
reach the airport area, and have never been seen above it. No other
species of salmon have been observed in or above the airport area.
Little local information was available on silver salmon but ADF&G
biologists did not believe that the run was very large or that spawning
occurred very far above the extent of tidal influence. With the close
proximity of the stream to the airport and the amount of recreational
activity occurring at or near the airport, it seems unlikely that
silvers would be present in any numbers (especially in a stream near a
community of commercial fishermen), with the local residents not being
aware of it.
Appendix E, page 8. Field investigations will be conducted in 1982 to
confirm the upper limits of chum, pink, and coho spawning, as noted
above (Comment on Section I, page 5).
Appendix E, page 14. The studies suggested appear to be unnecessary
based on site specific knowledge of the potential for losses due to this
project. If a significant number of coho salmon were to be found above
the project site, then appropriate mitigation measures would be included
in the final design.
Through interviews and discussions with local residents, local city
administrators, ADF&G biologists, staff members from Ecological Services
and the input from several site visits, existing knowledge of wildlife
and fisheries resources in the project area was incorporated into the
report •
With the exception of the confirmation of the upper limits of
spawning and the completion of the collection of the hydrological data
previously discussed, no additional environmental studies for this site
are contemplated.
Old Harbor:
Section I, page 5. The Old Harbor Hydroelectric Project does not appear
to warrant additional terrestrial habitat studies and/or mitigative
measures that could not be accomplished within the estimated project
cost.
Section I, page 6. The road is one half mile long and will be built
primarily through a sparse meadow community (with very little topsoil on
mostly alluvial deposits). The transmission line is 3 miles long and
crosses Big Creek. This crossing does present the potential for
collision by waterfowl that utilize the area. Appendix E, Sections I
through M, of the Feasibility Study, discussed wildlife utilization
impacts and mitigation in an adequate level for this study.
Keith Schrei ner
July 28, 1982
Page 4
Section II, page 5. During the recent meeting with ADF&G and USF&WS
personnel, it was generally agreed that consideration of mitigative and
replacement measures were premature for the Old Harbor Project and that
the fish and wildlife studies to date are sufficient for the present
level of project evaluation.
Section X, page 2. Good spawning gravel occurs only on the alluvial
fan. The remainder of the stream is steep and rocky. Above the weir,
the gradient flattens out and the gravel is potentially good for
spawning. However, it is doubtful many fish, particularly pink salmon,
would make it to this portion of the stream.
Section X, pages 3 & 4; Section XII, page 1. The small size and limited
potential impacts of this project do not warrant the extensive studies
outlined.
Enclosed with this letter is a reply to specific questions raised
in a memorandum dated April 16, 1982 from the acting Refuge Manager,
Kodiak NWR, to the staff of the Western Alaska Ecolooical Services,
which provides further site specific information. -
Through interviews and discussions with local residents, ADF&G
biologists, Kodiak NWR personnel, staff members from Ecological Services
and the input from numerous site visits, existing knowledge of wildlife
in the project area was incorporated into the report. This level of
information appears sufficient for project evaluation at this time.
Larsen Bay:
Section I, paae 5. The Larsen Bay Hydroelectric Project does not appear
to warrant ad itional environmental studies and/or mitigative measures
that could not be accomplished within the estimated project cost.
Section X, ~a~e 1. Due to the location of the existing cannery dam and
the marginaabitat existing between the proposed diversion weir and
the dam, it appears that fish passage structures would not be required.
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has been corrected.
As noted above, fish habitat above the existing cannery site dam is
marginal with a bedrock and boulder substrate, no pools, and very little
quiet water. At this time, the possible upper limit for pink salmon
spawning is the face of the cannery dam. However, as can be seen from
the photo provided on Page 8 of Appendix E, conditions for about
100 yards below the dam are marginal for spawning.
The drainage area for Humpy Creek above the proposed diversion weir
is 6.28 square miles. ~ean annual flow for this drainage area is
estima 3ed to bZ 13.0 ft /sec, resulting in a unit runoff of some
2.1 ft /sec/mi . The drainage area for that reach of the creek between
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July 28, 1982
Page 5
the diversion weir and powerhouse is computed to b~ 0.09 mi 2 The creek
within this reach could potentially release 0.2 ft /sec on a mean annual
basis; although, this estimate is conservative due to excess
streamflows, which must be spilled over the diversion weir during periods
of high flow.
Sources of streamflow for the reach of creek between the diversion
weir and powerhouse include:
Ground-water seepage from the narrow valley slopes.
Several rivulets and overland flow channels on the left valley
banks.
Runoff from the valley slopes during snowmelt and rainstorm events.
Seepage fro~ the diversion weir itself.
Al~o, the turbine generator is sized for a maxim~m design flow of
23.8 ft /sec. Stream flows in excess of this 23.8 ft /sec will spill
over the diversion weir. This situation would obviously only occur
during periods of high surface flows. Ultimately, spillage and
projected discharges will be a function of final design.
It is conceivable that short reaches of Humpy Creek below the
diversion weir may go dry during periods of minimum flow-late winter and
early spring. However, the streambed itself is expected to remain
saturated throughout the year.
Section X, ~age 4. The extent of wildlife habitat and its present use
are outline in Appendix E, pages 10 through 20. With the project area
being located in such close proximity to Larsen Bay itself, it would not
have much additional impact relative to fish and wildlife resources,
other than that which has already occurred.
Enclosed with this letter is a reply to specific questions raised
in a memorandum dated April 16, 1982 from the acting Refuge Manager,
Kodiak NWR, to the staff of the Western Alaska Ecological Services,
which provides further site specific information.
Through interviews and discussions with local residents, ADF&G
biologists, Kodiak NWR personnel, staff members from Ecological
Services, and the input from numerous site visits, existing knowledge of
wildlife in the project area was incorporated into the report. This
level of information appears sufficient for project evaluation at this
time.
Keith Schrei ner
July 28, 1982
Page 6
Togiak:
Section 1, page 1. Mitigation measures such as a fish passage are
included in this cost. If this project were to receive additional
funding, further work would need to be accomplished in order to scope
both impacts and possible mitigation measures.
Section VI, page 5. A recommendation for additional studies on
techniques to insure safe passage of outmigration smolt was included in
the draft report in Appendix E, page 46. This recommendation has been
clarified to show the potential need for changes in design.
Section X, page 1 & 2. It should be pointed out that Togiak was
intended to be only a reconnaissance study. It was understood that
additional studies would be required should this project be funded. At
that time, resource agencies would be invited to participate in scoping
these additional studies. Due to the marginal feasibility of this
project, we feel that any' discussion of additional studies at this time
is premature.
Section X, page 3. This change has been incorporated into the text.
Section XI, page 3. A one year program to collect stream discharge data
is presently being conducted.
Apeendix E, page 21. The potential for changes in stream morphology was
pOlnted out on this page. Due to the preliminary nature of this study,
a detailed analysis of potential impacts was not necessary at this
stage. Future or continued studies of this project would discuss these
potential changes in more detail.
Appendix E, pa*e 22. Mitigation measures will be discussed in more
detail in any uture studies of this potential project.
Because of the uncertain project status in regard to the Togiak
Reconnaissance Study and because some consideration is being given to a
different location on a different river, no further environmental
activities are contemplated for Quigmy River.
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July 28, 1982
Page 7
Thank you again for your consideration and timely input. The
Power Authority looks forward to a successful working relationship with
the U.S. Fish and Wildlife Service in bringing this project forward.
Enclosures:
c?
Eric P. Yould "-\
Executive Director
USFWS memo of April 16, 1982
APA reply of July 28 to the above memo
cc: FWS-ROES, WAES
ADF&G, NMFS, ADEC, OCM, Juneau
ADF&G, NMFS, ADEC, EPA, Anchorage
m
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April 14, 1982
hlaska Power Authority
334 West 5th Avenue
Anchorage, Alaska 99501
OFFICE 01lf~l{ft.1f~'t'd!
SAN FRANCISCO
lWR-MBH_
RNJ_N RR_
PEP_ CO DJC c:n -OCW_"'-OCR GVG_~ JWM=
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CTD_ CAL_
Attention: Eric P. Yould, Executive Director
Gentlemen:
JAY S. HAMMOND. GOYERNOR
P.O. BOX 3·2000
JUNEAU. ALASKA 99802
PHONE: 465-4100
RECElVt:O
!.?R 1 91322
po .. rt:~ A I ITU r"'t:: tTY P.iJ.SK.t.. J.~" r.~ •.. _,
Re: Feasibility Studies for King Cove Hydroelectric Project, Old Harbor
Hydroelectric Project, Larsen Bay Hydroelectric Project and
Reconnaissance Study for Togiak Hydroelectric Project
The Alaska Department of Fish and Game has reviewed the subject documents
and generally concurs with the contents. There are, however, several
informational needs and statutory requirements that need to be addressed.
These are outlined within the enclosed specific comments.
If you have any questions or comments, please do not hesitate to contact me.
Sincerely,
~
Ronald O. Skoog
Commissioner
cc: C. Yanagawa
R. Logan
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Volume B -Feasibility Study for King Cove Hydroelectric Project -Draft Report
SECTION X -ENVIRONMENTAL AND SOCIAL EFFECTS
B. ENVIRONMENTAL EFFECTS
1. Fi sheries
Page X-2, para. 3
Alaska Statute 16.05.840 requires that, if the Commissioner feels it
necessary, dams be fitted with fishways and devices for passage of fish.
This may necessitate a minimum f10w release thrQugh the stream reach below
the diversion weir.
SECTION XI -PROJECT IMPLEMENTATIONS
B. PROJECT LICENSES, PERMITS, AND INSTITUTIONAL CONSIDERATIONS
Page XI-l, general comment
Absent from the list of permit requirements is that pertaining to
AS 16.05.840 as follows:
"Sec. 16.05.840. Fishway required. If the commissioner considers it
necessary, every dam or other obstruction built by any person across a
stream frequented by sa 1 mon or other fi sh sha 11 be provi ded by that person
.....
We question the accuracy of some of the statements regarding substrate sizes
and other optimum spawning conditions, including those obtained from the
ADF&G 1978, Fisheries Atlas. Some work has already been conducted and other
is ongoing regarding development of species suitability curves for several
river systems in Alaska. While it should be recognized that curves
developed for species in one system cannot be directly applied to those in
another, they may be used in making qualified generalizations.
G. FISHERIES IMPACTS
Page 13, para. 3
Any habitat improvement accrued by retention of sediments will be negated by
'loss or absence of flow.
H. FISHERY MITIGATION
Page 14 & 15, general co~ments
The fisheries mitigation section fails to address measures other than
reduction of sedimentation. Other impacts such as loss of habitat in
dewatered streams reaches and impediment to fish migration must also be
addressed.
M. WILDLIFE MITIGATION
Page 24, para. 7
The 330 foot buffer cited here is a USFS reconmendation for minimum
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• •
separation for falling of trees. In instances where there is flexibility to ..
locate camps, material sites, etc. at a distance greater than 330 feet, we
recommend it be done. In addition, we suggest a minimum separation of 500
feet and strongly discourage siting within one-quarter mile.
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With respect to aircraft separation, we recommend 1500 feet separation ..
for helicopters and 500 feet for fixed wing craft.
Pages 24, general comments
.. .. .. -•
The wildlife mitigation section fails to address mitigation measures related_
to restoration of material sites, abandoned camp sites and utilization
transmission lines designed to minimize large raptor electrocution.
U. PERMITTING REQUIREMENTS
Pages 28-29, general comments
Absent from the list of permit requirements is that pertaining to
AS 16.05.840 as follows:
"Sec. 16.05.840. Fish\'I'ay required. If the commissioner considers it
necessary, every dam or other obstruction built by any person across a
of .. .. .. .. ..
• -• ..
• ..
• .. .. .. stream frequented by salmon or other fish shall be provided by that person
with a durable and efficient fishway and a device for efficie~t passage for • ..
downstream migrants. The fishway or device or both shall be maintained in a .. ..
• •
,,, ..
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.....
practical and effective manner in the place, fonn and capacity the
commissioner approves, for which plans and specifica-
tions shall be approved by the department upon application to it. The
fishway or device shall be kept open, unobstructed, and supplied with a
sufficient quantity of water to admit freely the passage of fish through it.
(Par. 30 pat 1 ch 94 SLA 1959)."
A Habitat Protection Permit constitutes approval under AS 16.05.840.
V. RECOMMENDATIONS
Page 31, general comments
We recommend that a determination of a minimum flow requirement to pass fish
between the weir and powerhouse be made. Knowledge of this figure and its
impact on power production will and in making the determination of necessity
to provide fish passage.
Volume C -Feasibility Study for Old Harbor Hydroelectric Project -Draft Rerort
SECTION X -ENVIRONMENTAL AND SOCIAL EFFECTS
B. ENVIRONMENTAL EFFECTS
Page X-2, 1. Fisheries
. Was any effort expended towards sampling for fish between the powerhouse and
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diversion weir site and above to ascertain use by fish? If not (as can be ..
concluded from the report), there is no way to predict the consequences of
habitat lost through dewatering or the impact of impeding fish migrations.
Page X-2, Z. Wildlife
Bear confrontations are likely to be the most serious wildlife consequence
of the project. Confrontations would be most likely from August through
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October when bear are feeding on salmon in Big Creek. If construction were II
• • executed other than in this time period, likelihood of this problem would be
considerably reduced. Precautions with disposal of garbage and other food
scraps (lunches, etc.) during construction will also reduce the potential
for bear problems.
Owing to the large number of bald eagles in the area, transmission line
designs which minimize large raptor electrocution must be e~ployed.
SECTION XI -PROJECT IMPLEMENTATION
B. PROJECT LICENSES, PERMITS, AND INSTITUTIONAL CONSIDERATIONS
Page XI-l, general comment
Absent from the list of permit requirements is that pertaining to
AS 16.05.840 as follows:
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"Sec. 16.05.840. Fishway required. If the commissioner considers it
necessary, every dam or other obstruction built by any person across a
stream frequented by salmon or other fish shall be provided by that person
with a durable and efficient fishway and a device for efficient passage for
downstream migrants. The fishway or device or both shall be-maintained in a
practical and effective manner in the place, form and capacity the
commissioner approves, for which plans and specifi-
cations shall be approved by the department upon application to it. The
fishway or device shall be kept open, unobstructed, and supplied with a
sufficient quantity of water to admit freely the passage of fish through it.
(Par. 30 pat 1 ch 94 SLA 1959)."
A Habitat Protection Permit constitutes approval under AS 16.05.840.
SECTION XII -CONCLUSIONS AND RECOMMENDATIONS
B. RECOMMENDATIONS
Page XII-l, general comments
We recommend that it be determined whether fish utilize that portion of the
stream that will be dewatered below the weir for either residence or as a
migration route. If it is used for either or both, a fishway and/or minimum
release may be required.
APPENDIX E -ENVIRONMENTAL REPORT
D. FISHERIES
Page 4-6 general comments
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•
We question the accuracy of some of the statements regarding substrate sizes ..
and other optimum spawning conditions, including those obtained from the
ADF&G 1978, Fisheries Atlas. Some work has already been conducted and other
is ongoing regarding development of species suitability curves for several
river systems in Alaska. While it should be recognized that curves
developed for species in one system cannot be directly applied to those in
another, they may be used in making qualified generalizations.
H. FISHERY MITIGATION
Page 9 & 10, general comments
The fisheries mitigation section fails to address measures other than
reduction of sedimentation. Other impacts such as loss of habitat in
dewatered streams reaches and impediments to fish migration must also be
addressed.
M. WILDLIFE MITIGATION
Page 22, para. 1
The 330 foot buffer cited here is a USFS recommendation for minimum
separation for falling of trees. 1n instances where there is flexibility to
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locate camps. material site, etc. at a distance 9i'eater than 330 feet, we
recommend it be done. In addition. we suggest a minimum separation of 500
feet and strongly discourage siting within one-quarter mile.
With respect to aircraft separation, we recommend 1500 feet separation
for helicopters and 500 feet for fixed wing craft.
Pages 21 & 22, general comments
The wildlife mitigation section fails to address mitigation measures related
to restoration of material sites, abandoned camp sites and utilization of
transmission lines designed to minimize large raptor electrocution.
U. PERMITTING REQUIREMENTS
Pages 26-28, general comment
Absent from the list of permit requirements is that pertaining to
AS 16.05.840 as follows:
"Sec. 16.05.840. Fishway required. If the commissioner considers it
necessary. every dam or other obstruction built by any person across a
stream frequented by salmon or other fish shall be provided by that person
with a durable and efficient fishway and a device for efficient passage for
downstream migrants. The fishway or device or both shall be maintained in a
practical and effective manner in the place, form and capacity the
commissioner approves, for which plans and specifi-
cations shall be approved by the department upon application to it. The
fishway or device shall be kept open, unobstructed, and supplied with a
sufficient quantity of water to admit freely the passage of fish through
(Par. 30 pat 1 ch 94 SLA 1959)."
A Habitat Protection Permit constitutes approval under AS 16.05.840.
V. RECOMMENDATiONS
Page 28, general comments
it.
We recommend that it be determined whether fish utilize that portion of the
stream that will be dewatered below the weir for either residence or as a
migration route. If it is used for either or both a fishway and/or minimum
release may be required.
Volume D -Feasibility Study for Larsen Bay Hydroelectric Project -Draft Report
SECTION X -ENVIRONMENTAL AND SOCIAL EFFECTS
B. ENVIRONM~NTAL EFFECTS
1. Fisheries
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Page X-3, para. 3
Alaska Statute 16.05.840 requires that, if the Commissioner feels it
necessary, dams be fitted with fishways and devices for passage of fish.
This may necessitate a minimum flow release through the stream reach below
the diversion weir.
Dolly Varden are identified as being trout. They are chars.
SECTION XI -PROJECT IMPLEMENTATION
B. PROJECT LICE~SES, PER~'ITS, AND INSTITUTIONAL CONSIDERATIONS
Page XI-l, general comment
Absent from the list of permit requirements is that pertaining to
AS 16.05.840 as follows:
US ec . 16.05.840. Fishway required. If the commissioner considers it
necessary, every dam or other obstruction built by any person across a
stream frequented by salmon or other fish shall be provided by that person
with a durable and efficient fishway and a device for efficient passage for
downstream migrants. The fishway or device or both shall be maintained in a
practical and effective manner in the place, form and capacity the
con~issioner approves, for which plans and specifica-
tions shall be approved by the department upon application to it. The
fishway or device shall be kept open, unobstructed, and supplied with a
sufficient quantity of water to admit freely the passage of fish through it.
(Par. 30 pat 1 ch 94 SLA 1959)."
A Habitat Protection Permit constitutes approval under AS 16.05.840.
SECTION XII -CONCLUSION AND RECOMMENDATIONS
B. RECOMMENDATION
Page XII-l, general comments
We recommend that a determination of a minimum flow requirement to pass fish
between the weir and powerhouse be made. Knowledge of this figure and its
impact on power production will aid in making the determination of necessity
to provide fish passage relative to AS 16.05.840.
APPENDIX E -ENVIRONMENTAL REPORT
D. FISHERIES
Page 5, general comments
An assessment of the fisheries resources present between the weir and
powerhouse should be made to determine the necessity of maintaining a
minimum flow and the advisability of constructing fish passage structures.
Page 6, para. 1-3
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We question the accuracy of some of the statements regarding substrate sizes
and other optimum spawning conditions, including those obtained from the
ADF&G 1978, Fisheries Atlas. Some work has already been conducted and other
is ongoing regarding development of species suitability curves for several
river systems in Alaska. While it should be recognized that curves
developed for species in one system cannot be directly applied to those in
another, they may be used in making qualified generalizations.
G. FISHERIES IMPACTS
Page 7, general comments
The presence of the weir and lack of flow will impede fish passage
throughout the affected reach.
H. FISHERY MITIGATION
Page 9 & 10, general comments
The fisheries mitigation section fails to address measures other than
reduction of sedimentation. Other impacts such as loss of habitat in
dewatered stream reaches and impediment to fish migration must also be
addressed.
M. WILDLIFE MITIGATION
Page 22, para. 7
The 330 foot buffer cited here is a USFS recommendation for minimum
separation for falling of trees. In instances where there is flexibility to
locate camps, material sites, etc. at a distance greater than 330 feet, we
.. ..
• •
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•
recommend it be done. In addition, we suggest a minimum separation of 500 ..
feet and strongly discourage siting within one-quarter mile.
With respect to aircraft separation we recommend 1500 feet separation
for helicopters and 500 feet for fixed wing craft.
Pages 24, general comments
• -• .. .. ..
•
III
The wildlife mitigation section fails to address mitigation measures related .•
to restoration of material sites, abandoned camp sites and utilization of
transmission lines designed to minimize large raptor electrocution.
U. PERMITTING REQUIREMENTS
Pages 26-29. general comments
Absent from the list of permit requirements is that pertaining to
AS 16.05.840 as follows:
"Sec. 16.05.840. Fish\'/ay required. If the commissioner considers it
nece5sary, every dam or other obstruction built by any person across a
stream frequented by salmon or other fish shall be provided by that person
with a durable and efficient fishway and a device for efficien~ passage for
downstream migrants. The fishway or device or both shall be maintained in a
..
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•
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prrtctical and effective manner in the place. form and capacity the
commissioner approves, for which plans and specifica-
tions shall be approved by the department upon application to it. The
fishway or device shall be kept open. unobstructed. and supplied with a
sufficient quantity of water to admit freely the passage of fish through it.
(Par. 30 pat 1 ch 94 SLA 1959)."
A Habitat Protection Permit constitutes approval under AS 16.05.840.
v. RECOMMENDATIONS
Page 31, general comments
We recommend that a determination of a minimum flow rec\uirement to pass fish
between the weir and powerhouse be made. Knowledge of this figure and its
impact on power production will aid in making the determination of necessity
to provide fish passage relative to AS 16.05.840.
Volume E
Reconnaissance Study for Togiak Hydroelectric Project -Draft Report
SECTION VI -ALTERNATIVE HYDROELECTRIC PROJECTS
Page VI-5, 5. Fish Ladder
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In addition to provisions to pass fish upstream consideration must be given _
to a means of providing passage of downstream migrants (fry, smolts and -
resident fish) without incurring significant mortalities. In many
instances, fish are unable to survive passage through turbines. In response
to this problem, a number of devices such as traveling screens and baffled
intakes have been developed.
SECTION X -ENVIRONMENTAL AND SOCIAL EFFECTS
A. GENERAL
Page X-I, para. 2
B.
With respect to recommendations for additional study, the upstream effects
of the impoundment on salmon and resident spawning and rearing habitat need
to be addressed. We also assume that downstream impacts to all salmon and
resident species will be addressed.
ENVIRONMENTAL EFFECTS
Page X-3, para. I
Dolly Varden are referred to as trout, they are char.
Page X-4, para. I
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Although it is generally known that chum salmon spawning is heaviest in the
lower one-half of the Quigmy River. distribution of all salmon species
should be verified in subsequent studies. This is an important factor when
determining requirements for minimum flows. In addition, it is recognized
that chum salmon typically spawn in areas of groundwater upwelling. If this
can be verified in the Quigmy River, it may have great significance
respective to flow release for fisheries.
SECTION XI -PROJECT IMPLEMENTATION
B. DEFINITIVE PROJECT REPORT
Page XI-3, 5. Hydrology
Statement is made that estimates are based on data from areas 75 to 150 feet
distant. Perhaps the distance is actually 75 to 150 miles .
D. PROJECT LICENSES, PERMITS, AND INSTITUTIONAL CONSIDERATIONS
Page XI-6, 3. ADF&G Permits
Statement is made that a Habitat Protection Permit is required for
Delta Creek. Should this refer to Quigmy River instead?
Absent from the list of permit requirements is that pertaining to
I
AS 16.05.840 as follows:
"Sec. 16.05.840. Fishway required. If the commissioner considers it
necessary, every dam or other obstruction built by any person across a
stream frequented by salmon or other fish shall be provided by that person
II
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• ...
•
•
• with a durable and efficient fishway and a device for efficient passage for _
o·
downstream migrants. The fishway or device or both shall be maintained in a ..
practical and effective manner in the place, form and capacity the
commissioner approves, for which plans and specifi-
cations shall be approved by the department upon application to it. The
fishway or device shall be kept open, unobstructed, and supplied with a
sufficient quantity of water to admit freely the passage of fish through it .
(Par. 30 pat 1 ch 94 SLA 1959)."
A Habitat Protection Permit constitutes approval under AS 16.05.840.
APPENDIX E -ENVIRONMENTAL REPORT
0.1. Spawning
Page 11, para. 2
Optimum stream velocity for coho salmon is cited as being 3-4 cubic feet
.second (cfs). This is a discharge quantity rather than one of velocity.
Page 12, para. 1
Dolly Varden are properly referred to as char rather than trout.
per
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Page 11 & 12, general comments
1.
We question the accuracy of some of the statements regarding substrate sizes
and other optimum spawning condition, including those obtained from the
ADF&G 1978 Fisheries Atlas. Some work has already been conducted and other
is ongoing regarding development of species suitability curves for several
systems in Alaska. While it should be recognized that curves developed for
a species in one system cannot be directly applied to those in another, they
may be used in making qualified generalizations.
FISHERIES IMPACTS
Page 21, para. 3
There may be streambed morphology changes associated with the project due to
attenuation of some flood events and lack of material recruitment from
reaches above the dam.
J. FISHERY MITIGATION
Page 22, para. 2
Is the inference here that improving the road as little as possible will
reduce the erosion potential? If so, we believe this to be an erroneous
conclusion. A maintained gravel surface of adequate dimensions will produce
far fewer fines than an unimproved surface •
Page 22, general comments
This discussion fails to address fisheries mitigation other than
sedimentation and erosion control. There is no mention of flow maintenance,
provision for safe passage of downstream migrants, provisions-for passage of
upstream migrants, etc.
Q. WILDLIFE MITIGATION
Page 36 & 37, general comments
of Discussion should also address mitigation measures related to restoration
disturbed areas, prohibition of vehicular access to project roads,
scheduling of construction events to minimize disturbance to wildlife, etc.
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE· ANCHORAGE, ALASKA 99501
-Mr. Rona 1 d Skoog
Commissioner
Alaska Department of Fish & Game
P.O. Box 3-2000
Juneau, AK 99802
July 28, 1982
Phone: (907) 277·7641
(907) 276·0001
Subject: Feasibility Studies for King Cove Hydroelectric project,
Old Harbor Hydroelectric Project, Larsen Bay Hydroelectric
Project and Reconnaissance Study for Togiak Hydroelectric
Project
Dear Commissioner Skoog:
This letter is in response to your letter of April 14, 1982 and the
subsequent meeting of April 28, 1982 discussing ADF&G's concerns about
the above referenced projects. Note that this meeting included several
representatives from the U.S. Fish & Wildlife Service as well as our
consultant, DOWL Engineers. We appreciate the constructive nature of
the comments and the time members of your staff spent in review and
discussion of these projects.
GENERAL COMMENTS APPLICABLE TO KING COVE, OLD HARBOR AND LARSEN BAY ARE:
The Habitat Protection Permit required by Section 16.05.840,
Fishway required, has been included in the list of permit
requirements. (Volume B, XI-2 and page 29, Appendix E; Volume C,
XI-2 and page 27, Appendix E; Volume D, XI-2 and page 27, Appendix
E) •
The ADF&G 1978, Fisheries Atlas was and is used at this time by
DOWL biologists as a basic reference for fisheries spawning
conditions. References provided by your staff and others relative
to on-going work in the development of species suitability curves
will be utilized for any future work at the project sites and
certainly in future projects to augment the basic information
currently available in the Fisheries Atlas for making qualified
generalizations for each river system.
o ADF&G's recommendations concerning minimum separation from active
bald eagle nests have been incorporated into the text (Volume B,
Appendix E, page 24; Volume C, Appendix E, page 22; and Volume D,
Appendix E, page 22).
o Restoration of material sites and abandoned camp sites has been
addressed in the final report (Volume B, Appendix E, pages 16 and
24; Volume C, Appendix E, page 21; Volume D, Appendix E, page 22).
Commissioner Ronald Skoog
July 28, 1982
Page 2
o Utilization of transmission lines designed to mlnlmlze large raptor
electrocution has been included as a mitigation measure (Volume B,
Appendix E, page 24; Volume C, Appendix E, page 22; Volume D,
Appendix E, page 22).
COMMENTS SPECIFIC TO KING COVE:
Page XII-I; Appendix E, p. 14, 15, & 31
Delta Creek
~1ean annual flow is 24 cfs for a dr~inage area of 3.63 square miles
resulting in a unit runoff of 6.6 cfs/mi. Drainage area between the
proposed dam site and powerhouse is 0.4 square miles. Sizing for
turbine generator is set at the 15 percent exceedance point which
corresponds to a flow of 44 cfs in the flow duration curve for
Delta Creek. This is the maximum turbine design flow. Any flows in
excess of design flow will be routed through the diversion weir spillway
and will flow into the stream channel below the dam. Flows less than
the maximum design flow will be completely diverted into the penstock.
This may result in short reaches of Delta Creek devoid of any observable
streamflow just below the dam although the tributaries and the
groundwater seepage from the valley slopes will maintain some estimated
minimum flows (less than 2 cfs) in most of that stream channel between
the dam site and the powerhouse. A flow duration curve is provided to
indicate the percent of time that streamflow in excess of maximum
turbine design flow (44 cfs) will be let go through an unregulated
spillway. See comments on Appendix E, page 13, below, for additional
discussion.
Appendix E, page 13, para. 3. Habitat improvement accrued by
retention of sediments: DOWL feels that sufficient flow from
groundwater and small tributaries will allow maintenance of resident
populations and that the decreased velocity and sediment load will
improve the available habitat. Additional field work to be performed by
DOWL Engineers in 1982 will address the actual utilization of the upper
portions of the system and minimal flow requirements between the weir
and powerhouse locations, as well as potential hatitat loss.
During our meeting of April 28, 1982 two concerns were stressed by
ADF&G: (1) provision of sufficient flows between the diversion weir and
the powerhouse to maintain the existing Dolly Varden population
(addressed previously in this letter) and (2) insurance of some
transport of sediment from above the diversion weir back into the stream
channel below the weir to provide for recruitment of spawning gravels.
DOWL feels that this would be possible but would require considerable
investigation to assume compliance with DEC w~ter quality standards.
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Commissioner Ronald Skoog
July 28, 1982
Page 3
COMMENTS SPECIFIC TO OLD HARBOR:
Page X-2, I & XII-I. Fisheries: Location of trap sites. Two
traps were set above the proposed powerhouse location. The report has
been corrected to reflect this effort (Appendix E, page 6).
Page X-2, 2. Wildlife: bear confrontations. Assuming no
unexpected delays, it should be possible to avoid construction for most
if not all of the time when bear concentrations will be present.
Precautions will be taken with the handling of garbage to avoid
attracting bears (Appendix E, page 21) .
Appendix E, pages 9, 10, & 28.
The drainage area for Midway Creek above the proposed diversion
weir is 2.2 square mile~. Mean annual flow for this drainage are~ is
estimated to be 10.5 ft /sec resulting in a unit runoff of 4.8 ft /sec/mi 2.
The drainage area for that 'reach of the creek between the diversion weir
and powerhouse is computed to be 0.08 square miles. From this small
drainage basin, the creek could drain on an annual basis some 0.4 ft 3/sec
of water.
Sources of streamflow below the proposed diversion site will
include:
D a significant tributary draining a small area to the east and
discharging 200-300 feet downstream of the proposed diversion weir .
D ground-water seepage from the valley slopes into the creek.
D seepage from the diversion weir .
D runoff from the valley slopes during snowmelt and rainstorm events.
!he turbine generator is sized for a maximum design flow of
19 ft /sec and any surplus will spillover the diversion weir during
periods of high flows .
It is conceivable that short reaches of Midway Creek just below the
diversion weir may be devoid of surface flow certain periods during the
year, (e.g. late winter low-flow periods). However, the streambed will
most likely remain saturated even during low flow periods and may
contain shallow ground water flow in the coarse bed materials. Some
loss of habitat for resident Dolly Varden could occur during these
periods.
Commissioner Ronald Skoog
July 28, 1982
Page 4
COMMENTS SPECIFIC TO LARSEN BAY:
Page X-3, para. 3. Dolly Varden: corrected.
Page 5, Appendix E. Fisheries resources above the powerhouse. The
minnow trap set above the existing dam and proposed powerhouse captured
one Dolly Varden. Additional trapping may be done in the future in
connection with on-going hydrologic studies.
As discussed in our meeting of April 28, 1982, consideration will
be given to removal of the old dam as a possible mitigation for the
current project impacts.
Page XII-I, Recommendation, Page VII-I, Appendix E, page 7,9, 10,
and 31.
The drainage area for Humpy Creek above the proposed diversion weir
is 6.28 square miles. ~ean annual flow for this drainage area is
estimated to be 13.0 ft /sec resulting in a unit runoff of 2.1 ft 3/sec.
The drainage area for that reach of the creek between the diversion weir
and powerhouse is computed to be 0.09 squ~re miles. The creek within
this reach could potentially drain 0.2 ft /sec on a mean annual basis
although this estimate is considered conservative due to the excess
streamflows which must be spilled over the diversion weir during periods
of high flows.
Sources of streamflow for that reach of the creek between the
diversion weir and powerhouse include:
o Considerable ground-water seepage from the narrow valley slopes.
o Several rivulets and overland flow channels on the left valley
banks.
o Runoff from the valley slopes during snowmelt and rainstorm events.
o Seepage from the diversion weir.
Th3 turbine generator is sized for a maxim~m design flow of
23.8 ft /sec. Streamflows in excess of 23.8 ft /sec will spillover the
diversion weir during periods of high surface flows.
It is conceivable that short reaches of Humpy Creek below the
diversion weir may go dry during periods of minimum flow-late winter and
early spring. However, the streambed itself is expected to remain
saturated throughout the year. Some loss of habitat for resident
Dolly Varden could occur during these periods.
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• Department Of Energy
Alaska Power Administration
P.O. Box 50
Juneau. Alaska 99802
Mr. Eric P. You1d
Executive Director
Alaska Pm',er Authority
334 West 5th Avenue
Anchorage, AK 99501
Dear ~1r. You1d:
RECEIVt:O
P,?R 1 91982
~I.ASKA P01J1ER AUTHORITY
April 15, 1982
These are our notes on the studies for King Cove, Old Harbor, Larsen Bay,
and Togiak hydro projects. We found the studies to be very complete and
well done. They certainly rank among the best we have recently reviewed.
We agree with the conclusion and recommendations that actions be
initiated to implement projects at King Cove, Old Harbor, and Larsen Bay.
All of the projects except Larsen Bay are based on synthesized hydrology
which should be carefully reviewed before a construction commitment is
made. Even Larsen Bay data is very minimal with one year rtcord. As the
studies acknowledge, significant local micro climates exist throughout
the region, especially on Kodiak Island.
We question whether or not energy could be sold for electric heat at the
same price as electric energy for other purposes, especially when
compared to the present and projected costs of oil.
We also question tht space heating efficiency rates used from heating
oil. The reports are using 70 percent efficiency. From our experience
and other recent reports, 60 percent may be a more realistic figure for
planning purposes.
For Larsen Bay, will the high growth rate occur even with new HUD houses
in light of the cannery being closed? A couple small items--pagc IV-9,
the 22kWh/gal. should be 11 kWh/gal. and on line 5, page IV-9 of the
Draft Report--"~1ay, 1978 11 shoul d be "Janua ry, 1980".
Thanks for the opportunity to comment.
;g~/d
~Robert J. Cross TV --Adilli ni s trator
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE -ANCHORAGE, ALASKA 99501
-Mr. Robert J. Cross
Administrator
Alaska Power Administration
P.O. Box 50
Juneau, Alaska 99802
July 28, 1982
SUBJECT: Draft Feasibility Reports of Hydroelectric Projects
Phone: (907) 277-7641
(907) 276-0001
at King Cove, Larsen Bay and Old Harbor; Draft Reconnaissance
Report of a Hydroelectric Project at Togiak.
Dear Mr. Cross:
Thank you for your letter of April 15th regarding the above
referenced reports. The following letter addresses issues and answers
questions contained in your letter. We appreciate the participation and
timely input of you and your staff in reviewing the draft reports.
Our responses to your comments are included below:
Paragraph III
Although we feel fairly comfortable with the synthesized hydrology
which resulted in close correlations utilizing three independent methods,
there is no substitute for actual field measurements over an extended period
of time. A stream gaging program has been initiated, and will continue
indefinitely on streams recommended for weir construction. Each project
will be re-evaluated based upon updated hydrology resulting from stream
gage recordings prior to making any construction commitment. Such a
commitment could occur as earlly as spring, 1983. at which time over one
full year of stream gage data would be available.
Pa ragraph IV
In this type of analysis. the dollars relate only to the value of
the oil that is displaced. and not to the projected sales price of the energy.
Paragraph V
Since this analysis relates to the value of displaced oil. using 70%
as a heating efficiency is a more conservative assumption than using
60%. 70% assumes that less oil is used and hence a lower quantity of
oil would be displaced by hydropower.
Pa ragraph VI
Demand forecasts are difficult to make, however, we believe that
have made a reasonable estimate. See text for the other suggested
changes.
Thank you again for your comments and timely input. Should
you have further questions regarding these projects, please contact
myself or Mr. Don Baxter of my staff.
{:er~lY'_
Eric P. Yould
Executive Director
we
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Weste~n Alaska Ecological Services
April 16, 1982
Page 'I"wo
F. A no-road alternative should be considered for both projects.
A major cost in both projects is road construction.
G. Both reconnaissance studies were conducted much too late in
the season to evaluate any in-stream fisheries concerns. Stucies
of the sort described cannot be used as a basis for evaluatio~
of potential damage to pink salmon. I realize neither stream
is considered a major salmon stream, but evaluations during the
pink salmon runs (June-July) should be made.
H. Under fishery impacts, it is stated that proper construction
tec~niques and timing can minimize fishery impacts. This is
true, but on both of these projects timing of construction activ-
ity will be impractical due to the short time window for the
constructl.on.
I. Under the wildlife mitigation section for both projects, it should
be required that all refuse be incinerated on site, then rCEi'JVec.
from the area -this is =ritical to reduce bear problems.
J. Archeologic surveys of all former Refuge lands to be disturbed
by project features are mandatory.
2. Specific Comments:
A. Larsen Bay Hydro Project
Section II A. -Potential maintenance problems, costs, and avail-
ability of parts will likely be worse with hydropower than diesel
systems, not the reverse as stated here.
E. Land Status -See general COll\l'llent A. above.
Figure IY-4 -Same as above -Land Status.
Section Y -Alternatives -See our general comment C. above.
Section VII E. -Installation of a large diesel generation plant
in 1982 ensures the development of demand for cheaper power,
i.e., hydro. Diesel plant should be installe~ concurrently with
hydro project.
Section X-2 Wildlife -page x-5 para. 3 -The potential abuse
discussed here must be more than just discourage; it must be
prevented. Before FWS can issue a permit to construct, we must
have assurances that vehicle access into the upper ridges will
not be aided or provided by this project. Such access must be
physically impossible; not just prohibited or discouraged. This
is an extremely critical issue.
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Western Alaska Ecological Services
P.lJril 16, 1982
Page Three
Section X-4 -See general co~ment J. above.
Section X-6 Recreation -Again, access· by 3-wheelers and other
ORV"s must be prevented, not just discouraged.
Section XI-B.B -Should note that subsurface estate remains
with U. S.
Appendix E -Environment31 Report:
D. Fisheries -Studies should be done in June to properly
evaluate pink salmon use in this stream.
M. Wilclife Mitigation-para 2 -Refuse should be incinerated
on site then removed from the area as soon as possible.
Another mitigation factor should be added to ensure raptor-
proof lines and poles.
S. Socioeconomic Impacts -Why is a distribution system not
inrll1r'1pr1?
T. Land Status -Subsurface estate ...... i th u. S. as stated above.
B. Old Harbor Hydro Project
-Land status errors as described above.
-From a wildlife, fisheries and the Refuges standpoint, alter-
native site no. 1, Ohiouzuk Creek, would be a much more acceptable
project. Reasons for selecting site no. 2 given here are not
very definitive and should be clarified. Site number 1 would
be our preference. Cost differences may not be sufficient to
~ffect wildlife concerns on this project.
-Our previous comments on vehicle use apply to this project
as well.
Section B-1 Fisheries -Studies should be done in June, July
to evaluate pink salmon use.
Section B-4 -An archeologic reconnaissance would be required
by FWS.
Western Alaska Ecological Services
F,pril 16, 1982
Fage Four
Apendix D:
D. Fisheries -Surveys must be done June, July ~s l'rc'Jiu'.:sly
stated.
I. Wildlife -~lountain goats were introduced to Ug2.k £3.1', n':.ot
Uyak.
Again, ORVis must be restricted.
M. Mitigation -Refuse incinerated en site and rapter-proof
transmission line.
O. Archeologic survey of entire project is required by F~S.
T. Subsurface estate remains in U. S. Government.
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In sUITUTlary I both project reports appear extremely well don(' and very tht)rough. ..
The few relatively minor (for the most part) changes suggested here sh::'>uld
be considered. •
l,pproval by FWS of either project should be withheld until F\'i"S Refuge a:lj
\·:/"E5 personnel have comFleted an on-the-ground assessment (,f the proJect
ilreas. I suggest we try to accomplish same this summer in June cr Jul,/.
I t should be possible to complete such an assessment in one or t· .... o d .. .tys
per project.
Thank you for the opportunity to comment.
~~TV / jb
cc: Larry Calvert, OMS
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE· ANCHORAGE, ALASKA 99501
-Ms. Mary Lynn Nation
Western Alaska Ecological Services
U. S. Fish and Wildlife Service
605 West 4th Avenue, Room G-81
Anchorage, Alaska 99501
Dear Ms. Nation:
July 28, 1982
Phone: (907) 277·7641
(907) 276·0001
This letter is in response to the April 16, 1982 memorandum to your
office from the Acting Refuge Manager, Kodiak Nt·JR. The comments
contained in that memorandum were constructive in nature and we
appreciate this opportunity to provide you with additional information
and/or a response.
GENERAL COMMENTS:
1A. An indepth search for land status information has affirmed, in
part, the statement made by Mike Vivian in regard to the subsurface
estate within the Kodiak National Wildlife Refuge. PLO 1634,
Kodiak National Wildlife Refuge, excluded an area one mile square
surrounding the village of Larsen Bay and it was not until
PL 92-203, and later PLO 5183 and 5184, that the entire township of
T. 30 S., R. 29 W., S.M. was included within the Kodiak National
Wildlife Refuge.
Subsurface estate has consequently been conveyed to Koniag, Inc.
within the NWR boundary, as it exists today .
I~ary Nation
July 28, 1982
Page 2
The following is a BLM listing as of May 11, 1982, of
subsurface interim conveyances and patents in Sections 31 and 32 of
the above mentioned township:
Serial Conve~ance Section Ali 9. Parts Lot Acres
-CP 52780090 31 12 11. 370
CP 52780090 31 13 7.580
CP 52780090 31 14 8.361
1C 02000118 31 15 10.000
1C 02000118 31 16 5.000
CP 52780090 31 NENESE 10.000
CP 52780090 31 SWNESE 10.000
1C 02000118 31 S2SE 30.000
1C 02000118 32 3 2.000
CP 52780090 32 10 3.930
CP 52780090 32 9 8.530
CP 52780090 32 11 8.090
CP 52780090 32 10.000
CP 52780090 32 20.000
1C 02000118 32 8 10.940
1C 02000118 32 7 1.000
CP 52780090 32 SW 95.000
1C 02000118 32 2.370
1C 02000118 32 SENW 30.000
As a further note, the Secretary of the Interior may withdraw and
convey lands out of the National Wildlife Refuge System to the
appropriate Native Corporation for title. This applies to existing
cemetery sites and historical places, which may be conveyed to a
Native group that does not qualify as a Native village. Title to
the surface estate in not more than 23,040 acres surrounding the
Native groupsl locality may occur, with the subsurface estate being
conveyed to the appropriate Regional Corporation. Furthermore,
lands may be conveyed to an individual Native, however, the surface
estate may not exceed 160 acres and must be occupied by the Native
as a primary place of residence on August 31, 1971. The subsurface
estate would again be conveyed to the appropriate Regional
Corporation. This is pursuant to Section 14(h) of PL 92-203.
The land status text and land status map for Larsen Bay has been
changed to reflect the corrected land status based on this
information.
The land status text and land status map for Old Harbor has been
changed to reflect your comment.
lB. This stipulation has been incorporated into the mitigation section.
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.July ~R, 1982
Page 3
1C. A previous study by CH2M Hill entitled "Reconnaissance Study of
Energy Requirements and Alternatives for Akhiok, King Cove, Larsen
Bay, Old Harbor, Ouzinkie and Sand Point" June, 1981, looked at a
number of alternatives for the communities of Larsen Bay and Old
Harbor, and hydropower was judged to be the most feasible. Also,
the U. S. Amy Corps of Engineers had previously suggested
hydropower alternatives for these communities. The current study
focuses on the recommendations of these previous studies. The
final report will contain an analysis of a wind power generation
alternative for the communities.
10. The report states that frazil ice is a potential problem, but that
there are a number of workable solutions that will not seriously
affect the benefit/cost ratios for each of the projects. After
careful review, if found to be necessary, one or more of the
solutions suggested in the report will be incorporated during final
design.
IE. Use of off-the-road vehicles beyond the terminus of the maintenance
road is not possible due to steep cliffs. Vehicles would be
prohibited except for maintenance purposes. This comment has been
incorporated into the text.
IF. Because of requirements generated by dam construction and
subsequent maintenance operations, a road is required.
1G. Neither the Larsen Bay Hydroelectric Project nor the Old Harbor
Hydroelectric Project appear to warrant additional environmental
studies. At Larsen Bay, the powerhouse discharge will be at the
existing cannery dam, which presently blocks further upstream
migration. At Old Harbor, suitable spawning habitat is subject to
loss of flow during winter cold periods, so that survival of
incubating eggs is not likely. In addition, Ken Manthey, AOF&G
biologist in Kodiak, has indicated that he has flown over Midway
Creek several times while doing aerial escapement counts on other
streams in the area, and that he has never seen any salmon in
Midway Cree k .
1H. Under the present schedule, construction would begin in June and it
is possible that instream work could be completed before July 1,
when returning adults may be present. In addition, this is only a
general schedule subject to revision, and there is still room for
some flexibility.
II. This has been incorporated into the mitigation section.
1J. An archaeologic survey will be completed prior to project
construction.
Mary Nation
July 28, 1982
Page 4
SPECIFIC COMMENTS:
A. Larsen Bay Project.
Section II A.
E.
Costs are greater and parts more difficult to obtain for hydropower
systems; however, the probability of needing such maintenance for
hydropower systems is substantially lower than for a diesel
generation plant.
Land Status. See lAo
Figure IV-4. See lAo
Section V. See lC.
Section VII E.
Concurrent installation of hydro and diesel power will be
considered.
Section X-2.
Vehicle access into the upper ridges will not be aided by the
project.
Section X-4.
An archaeologic survey will be done prior to initiation of
construction.
Section X-6 Recreation. Agreed.
Section XI-B.8. See General Comment lAo
Appendix E:
D. See General Comment lG.
M. Agreed; these comments have been incorporated into the mitigation
plan.
S. A distribution system is a very common installation. There would
be no major socioeconomic impacts other than the minor
inconvenience caused during construction of the system.
T. Note General Comment lAo
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July 28, 1982
Page 5
B. Old Harbor Project.
The land status comments have been incorporated.
Midway Creek is preferable to Ohiouzuk Creek from both a geotechnical
and hydrological perspective. Furthermore, the Midway Creek site
satisfies the needs of the community. This is clearly indicated in
Section V, Pages 1 through 4, of the report.
Vehicle Usage, See Genera 1 Comment IE.
Section B-1, See General Comment 1G.
Section B-4, See Genera 1 Comment IJ.
Appendix 0:
D. , See General Comment IG.
I. This typographical error has been corrected. Also, see Section
X-2.
M. This has been incorporated into the mitigation section.
O. An archaeologic survey will be done prior to the initiation of
project construction.
T. See General Comment lA.
Thank you agai!1 for the constructive comments. We certainly
appreciate your timely input and look forward to a successful working
relationship with the U. S. Fish and Wildlife Service in bringing this
project forward.
cc: Larry Calvert, OMS
C~\~~
Eric P. Yould "\
Executive Director
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ALASKA POWER AUTHORITY
334 WEST 5th AVENUE· ANCHORAGE, ALASKA 99501
Mr. John E. Cook
Regional Director, Alaska Region
U.S. Department of the Interior
National Park Service
Alaska Regional Office
540 W. Fifth Avenue
Anchorage, Alaska 99501
July 28, 1982
SUBJECT: Draft Feasibility Reports of Hydroelectric Projects
Phone: (907) 277·7641
(907) 276·0001
at King Cove, Larsen Bay and Old Harbor; Draft Reconnaissance
Report of a Hydroelectric Project at Togiak.
Dear Mr. Cook:
Thank you for your letter of April 19th regarding the above
referenced reports. We appreciate your participation and timely input
in reviewing the draft reports.
In response to the question raised in your letter, the
State Historic Preservation Office was contacted and has commented on
the proposed projects. Copies of all relevant correspondence will be
included in the final feasibility reports.
Should you have further questions regarding these studies, please
contact myself or Mr. Don Baxter of my staff.
EPY:jls
<Ee:e1S? \ \ JJ.
Eric P. Yould '\
Executive Director
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LARSEN BAY HYDROELECTRIC PROJECT
FEASIBILITY STUDY
APPENDIX G
SPACE HEATING INSTALLATION
AND COST
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APPENDIX G
UTILIZATION OF EXCESS ELECTRICAL ENERGY
FOR SPACE HEAT
During much of the year the hydro unit can provide all of
the electrical needs for the community. In addition there
could be excess water for electric power to be used in space
heat ing. This excess could displace the use of substantial
amounts of fuel oil.
SYSTEM PARAMETERS
1. The system must use only hydro generated power which is
excess. It must be deactivated whenever diesel generators
are on the line.
2. The system must use as much of the excess as possible.
3. The system must not overload the hydro unit electrically or
mechanically.
4. It must not force the hydro to draw more water than the
stream can provide.
5. It must have remote capability to control the loads,
adjusting the heating loads to the available energy.
6. It must be compatible with existing heating systems.
7. It must be reliable because service is not readily
available .
NBISF-426-9523-AG 1
IMPLEMENTATION
A very simple method would be to install a separate meter
at each user, connect heaters and limi ting thermostats, and
then switch them off and on manually. This approach would work
reasonably well at times of very high water flow, but would
require a good deal of effort from the operator at periods of
marginal flow. In all probabil i ty this would lead to great ly
reduced use of the resource.
A more automatic system is probably justified. This system
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is envisioned as follows: •
The main control would be a control computer programmed in
control basic language and capable of storing its programming
in a non-volatile media, eliminating battery backup. Interface
systems would allow the unit to interpret a water level signal
from the dam, drive a keyboard and monitor, interpret dry
contact closures, and run a line driver capable of
communicating with the remote heating loads.
At the user end would be a control which would respond to
the computer command to turn on heaters. The user equipment
could take several forms as described below.
Operation
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1. The control would sense that only the hydro unit is on the _
line by checking the diesel unit circuit breakers.
2. The water level behind the dam would be checked to see that
excess water was available and going over the spillway.
3. The hydro is checked to see that it has excess generation
capacity.
NBISF-426-9523-AG 2
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4. The control begins sending signals to turn on heaters at
the user locations rechecking items 1, 2, and 3 after each
increment. This is a slow process, perhaps over 10
minutes.
5. If the water level drops or the generator approaches full
load, the controller reduces the heating load. This can
happen quickly.
This same control computer could also be used to limit the
hydro water flow by regulating the governor setting and to
start the diesels if more generation was required. It could
control up to 64 remote units in its basic form.
COST ESTIMATE .
The design of this system is qui te preliminary and highly
dependent on final hydro design and nature of heating systems
to be served. The system designs for small and large users are
shown as Figures G-1 and G-2.
It is assumed that the first priori ty heat loads would be
the schools and other public buildings. This tends to spread
the benefits evenly among the tax payers and are more cost
effective to connect.
Major components are estimated as follows:
Dam Water Level Sensors,
Cable, and Transducers
Control Computer and Inter-
face Installed
Electric Heating Equipment,
Boilers or Baseboard Heat
Control Signal Wiring to
Connect Computer to Users
NBISF-426-9523-AG 3
This item is part of
hydro estimate.
$10,000
Installed cost -
$40 per kW
$ 5,000
Software Development and
Fiel d Installation
User Controls, kWh Meters,
Cost for Entire System
$ 5,000
Assumes $15,000
spread over three
projects
$12,000
The cost estimate for the Larsen Bay system is summarized
on Table G-l.
NBISF-426-9523-AG 4
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TABLE G-1
SPACE HEATING INSTALLATION
LARSEN BAY HYDROELECTRIC PROJECT
Item Quantity Unit Unit Price
Control Computer 1 LS $10,000
and Interface
Electric Heating 200 KW 40
Equipment
Control Signal Wiring 1 LS 5,000
Software Development 1 LS 5,000
and Installation
User Controls and 1 LS 12,000
Meters
TOTAL
NBISF-426-9523-G-1
Amount
$10,000
8,000
5,000
5,000
12,000
$40,000