HomeMy WebLinkAboutKnutson Creek Hydroelectric Feasibility Study - Nov 2013 - REF Grant 7060976KNUTSON CREEK
HYDROELECTRIC FEASIBILITY STUDY
FINAL REPORT
NOVEMBER 2013
Prepared for
PEDRO BAY VILLAGE COUNCIL
P.O. BOX 47020
PEDRO BAY , ALASKA 99647
Prepared by
polarconsult alaska, inc.
1503 WEST 33
RD AVENUE, SUITE 310
ANCHORAGE, ALASKA 99503
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EXECUTIVE SUMMARY
In 2010, the State of Alaska funded the Pedro Bay Village Council (PBVC) to complete a
feasibility study of a hydroelectric project on Knutson Creek near Pedro Bay Village. In July
2010, the PBVC retained Polarconsult Alaska, Inc. (Polarconsult) to complete the feasibility
study. This report presents the results of the feasibility study.
Polarconsult has determined that a hydroelectric project on Knutson Creek is feasible from
technical, regulatory, and economic standpoints. The recommended project is estimated to
supply 95.6% of PBVCs current annual electric demand, and approximately
2/3rds of the villages
total building heating needs through interruptible electric heating services.
1 The recommended
project provides for significant future utility load growth and is estimated to lower the cost of
electricity for the community by up to 92%, depending on permit terms, financing, final
installed cost, and utilization of excess energy through interruptible electric heating services.
This study evaluated run of river hydroelectric project configurations at Knutson Creek with
installed capacity ranging from 100 to 1,000 kilowatts (kW), and finds that a 100 to 250 kW
project is best suited to the villages long term needs. The economic analysis identified a 200
kW hydroelectric project as the most cost effective configuration.
The 200 kW project has a design flow of 18.25 cubic feet per second (cfs), which is conveyed
from a diversion and intake structure at river mile (RM) 2.59 down to a hydro powerhouse near
RM 1.25 via a 26 inch diameter, 7,080 foot long penstock. Total gross head is 223.8 feet, and
net operating head at full flow is 206.5 feet. The hydro powerhouse is connected to the
villages existing electric distribution system via a 9,900 foot long buried power cable. The
project includes 16,400 linear feet of new roads and trails.
Table ES 1 Summary of Features for 200 kW Project
PROJECT FEATURES VALUE
Project Design Flow 18.25 cfs
Normal Headwater Elevation 398.5 feet
Normal Tailwater Elevation 174.7 feet
Gross Project Head 223.8 feet
Penstock 7,080 feet of 26 inch HDPE
Net Project Head at Full Flow 206.5 feet
Turbine Type Single Crossflow Turbine
Installed Generating Capacity 200 kW
Plant Capacity Factor 85.8%
Primary Power Lines 9,900 feet
Communications Lines 18,000 feet
Access Trails 16,400 feet
1 Terms are defined in the Acronyms and Terminology section of this report.
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Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
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To capture the full benefits of a hydro project on Knutson Creek, the village will have to refit its
community buildings and homes with interruptible electric heating systems. Interruptible
electric heating systems powered by the hydro project will supply approximately 85% of the
annual space heating needs of seven community buildings and approximately 53% of the space
heating needs of all 33 homes in the village. Existing electric utility load will use 12% of the
total energy output of the hydro project, and interruptible electric heating services will use
another 73%. The remaining 15% of project output occurs during the summer months and is
unused, but is available for future growth or new beneficial applications.
The recommended project was evaluated under several hypothetical load growth scenarios and
maintains a BCR of greater than 1 over a range from 45% to at least +570% of existing utility
load. Economic analysis of the project indicates it has a benefit cost ratio of between 1.18 and
2.00 compared to continued reliance on the diesel power plant.
Project economics include the benefits realized from interruptible heating applications. If
interruptible heating applications are not developed in conjunction with the hydro plant, the
project benefits are limited to the value of fuel displaced at the diesel power plant, and the
benefit cost ratio is approximately 0.6 to 0.8.
Table ES 2 Summary of Project Performance and Economics
PROJECT FEATURES VALUE
ENERGY PERFORMANCE OF RECOMMENDED PROJECT
Total Annual PBVC Prime Load Supplied by Diesel Plant 8,100 kWh (4.4%)
Total Annual PBVC Prime Load Supplied by Hydro Plant 174,100 kWh (95.6%)
Total Annual PBVC Prime Load (at generation) 182,200 kWh
Total Hydro Energy Dispatched to Supply PBVC Prime Load 174,100 kWh (11.6%)
Total Gross Excess Energy Dispatched to Interruptible Electric Heating Services 1,090,300 kWh (72.5%)
Remaining Excess Hydro Energy 239,300 kWh (15.9%)
Total Annual Hydro Generation 1,503,700 kWh
ECONOMIC EVALUATION OF RECOMMENDED PROJECT
Estimated Total Installed Cost (permitting, design, and construction) $4,502,000
Annual Reduction in Utility Fuel Purchases due to Hydro Project 16,600 gallons
Annual Reduction in Heating Fuel Purchases due to Interruptible Electric Heating Services 24,200 gallons
BENEFIT COST ANALYSIS
Debt Financed
Project
Grant Financed
Project
Present Value of Project Benefits $7,334,000 $8,280,000
Present Value of Project Costs $6,234,000 $4,132,000
BENEFIT COST RATIO OF RECOMMENDED PROJECT 1.18 2.00
Estimated Electric Rate with Hydro Project (Standard Service)$1.255 per kWh $0.065 per kWh
(Interruptible Heating Service)$0.198 per kWh $0.065 per kWh
kWh kilowatt hours
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Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report iii
The bypass reach of the recommended project includes the upper one mile of anadromous fish
habitat in Knutson Creek, and the project will significantly decrease flow in this reach during the
winter months. Fish surveys in 2012 indicate the affected reach receives approximately 100
adult Sockeye salmon. The entire 1.59 mile project bypass reach is also resident fish habitat.
Based on consultations with the Alaska Department of Fish and Game, the feasibility analysis
includes an in stream flow reservation of 6.6 cfs at the diversion site, which is ½ of the median
annual minimum flow in Knutson Creek. A flow reservation would also be supplemented by
significant inflow from tributaries that discharge into Knutson Creek along the project bypass
reach.
In stream flow reservations will have a significant impact on the projects generating capacity
during the winter months, and should be minimized to the extent appropriate through the use
of off site mitigation. This report quantifies the cost of in stream flow reservations to the
village, and identifies promising off site mitigation projects in the immediate project area.
Based on the findings in this study, continued development of this project is warranted. Under
reasonable permitting and financing schedules, the project can be built and commissioned in
2016. The following actions are recommended to advance this project.
(1) Initiate the permitting process for the project. Key permitting activities include
determining whether the project is under the jurisdiction of the Federal Energy
Regulatory Commission, and continuing dialog with the Alaska Department of Fish
and Game regarding fish habitat permit conditions.
(2) Continue collecting hydrology data at the diversion, gauging station, and tailrace sites
along Knutson Creek, as well as at tributaries R1 and L1, to support efforts to secure a
fish habitat permit with reasonable conditions for the project.
(3) Advance designs for the project. Once permit conditions are known, the project
economics and installed capacity should be reviewed to finalize the installed capacity
for the project.
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REPORT PURPOSE, LIMITATIONS, AND COPYRIGHT NOTICE
Purpose of this Report
A feasibility study is the second stage of screening for a potential hydroelectric project, and
represents a comprehensive review of relevant factors that pertain to the technical, economic,
environmental, and political viability of developing a hydroelectric project at a given site or for
a given power need. Depending on the available budget and the quality of existing information,
the feasibility study may include field data collection for key information necessary to complete
a technical, economic, and environmental review of the proposed project.
This feasibility study provides the Pedro Bay Village Council (PBVC) an in depth assessment of
the overall feasibility of a hydroelectric project at Knutson Creek, and provides information on
the advantages and disadvantages associated with various project sites and configurations.
This information is intended for use by the PBVC to decide whether to proceed with project
development.
Limitations
In conducting our analysis and forming the opinions and recommendations summarized in this
report, Polarconsult has relied on information provided by others, and has assumed this
information is complete and correct. Also, Polarconsult has made certain assumptions with
regard to future events, conditions, and circumstances. Polarconsult does not guarantee the
accuracy of the information, data, or opinions contained herein. The methodologies employed
to perform the analysis and arrive at the conclusions in this report follow generally accepted
industry practice for this level of study. We believe that the assumptions and methodologies
used are reasonable and appropriate for meeting the objectives of this study. Future events
and information may result in outcomes materially different from those projected in this study.
Such events and information include, but are not limited to, future energy demand, supply, and
cost in Pedro Bay; actual site conditions such as ownership, topography, hydrology, and
geology; future trends in local construction, material, and labor costs; and national, state, or
local policies that may affect aspects of the project.
The contents and findings of this report are limited to potential development of a hydroelectric
project at Knutson Creek by the PBVC, and are suitable only for this intended purpose. Any use
of this report and the information contained therein constitutes agreement that (1)
Polarconsult makes no warranty, express or implied, relating to this report and its contents, (2)
the user accepts sole risk of any such use, and (3) the user waives any claim for damages of any
kind against Polarconsult. The benefit of such waivers, releases, and limitations of liability
extend to Polarconsult, its subcontractors, owners, employees, and agents.
Copyright
This report is copyright protected by Polarconsult and may not be reproduced in whole or part
without the prior written consent of Polarconsult. The PBVC has the right to reproduce and use
this report for purposes related to hydroelectric development of Knutson Creek including,
without limitation, the right to deliver this report to regulatory and funding entities in support
of, or in response to, their inquires and proceedings.
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TABLE OF CONTENTS
EXECUTIVE SUMMARY..............................................................................................................I
ACRONYMS AND TERMINOLOGY............................................................................................VI
1.0 INTRODUCTION............................................................................................................1
1.1 PROJECT AUTHORIZATION AND PURPOSE ....................................................................................1
1.2 SUMMARY OF FINDINGS ...........................................................................................................1
1.3 PROJECT EVALUATION PROCESS .................................................................................................2
1.4 CURRENT AND PREVIOUS STUDIES ..............................................................................................4
2.0 COMMUNITY PROFILE..................................................................................................7
2.1 COMMUNITY OVERVIEW...........................................................................................................7
2.2 EXISTING ENERGY SYSTEM ........................................................................................................7
3.0 RECOMMENDED PROJECT.......................................................................................... 17
3.1 RESOURCE DESCRIPTION .........................................................................................................17
3.2 OVERVIEW OF RECOMMENDED PROJECT ...................................................................................18
3.3 DESCRIPTION OF PROJECT FEATURES ........................................................................................22
4.0 ECONOMIC ANALYSIS................................................................................................. 27
4.1 COST ESTIMATE FOR RECOMMENDED PROJECT ..........................................................................27
4.2 ECONOMIC EVALUATION OF RECOMMENDED PROJECT ................................................................28
4.3 PROJECTED ELECTRICITY RATES WITH RECOMMENDED PROJECT ....................................................30
4.4 SENSITIVITY ANALYSIS ............................................................................................................32
5.0 CONCLUSIONS AND RECOMMENDATIONS................................................................. 35
6.0 REFERENCES ............................................................................................................ 37
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APPENDICES
APPENDIX A PROJECT MAPS
APPENDIX B SITE PHOTOGRAPHS
APPENDIX C HYDROLOGY DATA
C.1 Available Hydrology Data
C.2 Stream Gauge Station Information
C.3 Flow Measurements and Station Calibration
C.4 Knutson Creek Hydrology Data
C.5 Knutson Creek Hydrology Model
APPENDIX D RESOURCE DATA AND ANALYSIS
D.1 Maximum Probable Flood
D.2 Review of Climate Effects on Hydropower Projects
D.3 Geotechnical Considerations
APPENDIX E ENVIRONMENTAL CONSIDERATIONS
E.1 Threatened and Endangered Species
E.2 Fisheries and Wildlife
E.3 Water and Air Quality
E.4 Wetland and Protected Areas
E.5 Archaeological and Historical Resources
E.6 Land Development Considerations
E.7 Telecommunications and Aviation Considerations
E.8 Visual and Aesthetic Resources
E.9 Mitigation Measures
APPENDIX F PERMITTING INFORMATION
F.1 Federal Permits
F.2 State of Alaska Permits
F.3 Local Permits
F.4 Other Permits and Authorizations
APPENDIX G COST ESTIMATES AND ECONOMIC ANALYSIS
G.1 Project Cost Estimate
G.2 Economic Analysis and Assumptions
G.3 Estimated Utility Electric Rates with Recommended Project
APPENDIX H TECHNICAL ANALYSIS
H.1 Hydro Project Modeling
H.2 Project Sizing Analysis
H.3 Evaluation of In Stream Flow Reservations
H.4 Different Utility Load Scenarios
APPENDIX I DRAFT REPORT REVIEW COMMENTS AND RESPONSES
APPENDIX J TABULAR HYDROLOGY DATA
APPENDIX K CONCEPTUAL DESIGN DRAWINGS
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LIST OF FIGURES
Figure 1 1 Feasibility Evaluation Process Flowchart................................................................3
Figure 2 1 Recent Monthly Peak and Average Power Generation........................................10
Figure 2 2 Recent Electric Utility and Electricity Costs..........................................................15
Figure 3 1 Typical Hydro Energy Output and Utilization, Recommended Project................21
Figure 5 1 Project Development Schedule ............................................................................36
Figure A 1 Project Overview and Location Map ......................................................................2
Figure A 2 Map of Recommended Knutson Creek Project ......................................................3
Figure A 3 Knutson Creek and Iliamna River Drainage Basins and Subbasins.........................4
Figure C 1 Stage Discharge Curve for Knutson Creek Upper Gauging Station........................6
Figure C 2 Stage Discharge Curve for Knutson Creek Lower Gauging Station ........................7
Figure C 3 2010 2012 Knutson Creek Stage and Temperature Data.....................................10
Figure C 4 2010 2012 Knutson Creek Flow Data ...................................................................10
Figure C 5 Daily Flow Statistics for Knutson Creek Based on Extended Record....................12
Figure C 6 Flow Duration Curves for Knutson Creek at Proposed Intake Site.......................13
Figure D 1 Bedrock Geology of the Project Area .....................................................................6
Figure D 2 Surficial Geology of the Project Area......................................................................7
Figure E 1 Estimated Knutson Creek Flow at RM 2.1 (Top of Anadromous Habitat).............. 5
Figure H 1 Typical Daily Performance of Recommended Hydro Project.................................5
Figure H 2 Annual Performance Of Recommended Hydro Project (1996 through
2011)....................................................................................................................... 6
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LIST OF PHOTOGRAPHS
Photograph B 1 Exterior View of Existing Pedro Bay Diesel Power House........................B 2
Photograph B 2 Interior View of Existing Pedro Bay Diesel Power House........................B 2
Photograph B 3 Upper Gauging Station Looking Upstream..............................................B 3
Photograph B 4 Natural Outlet Control Structure at Upper Gauging Station...................B 3
Photograph B 5 View of Knutson Creek Reach at Lower Gauging Station........................B 4
Photograph B 6 View of Knutson Creek Lower Gauging Station.......................................B 4
Photograph B 7 View of Knutson Creek at River Mile 2.2, Looking Upstream..................B 5
Photograph B 8 View of Knutson Creek at River Mile 1.5, Looking Downstream.............B 5
Photograph B 9 View of Knutson Creek Downstream of Upper Gauging Station.............B 6
Photograph B 10 Oblique Aerial View of Lower Knutson Creek..........................................B 8
Photograph B 11 Oblique Aerial View of Upper Knutson Creek..........................................B 8
Photograph B 12 Proposed Knutson Creek Diversion Site Looking Downstream...............B 9
Photograph B 13 Proposed Knutson Creek Diversion Site Looking Upstream..................B 10
Photograph B 14 Oblique View of Proposed Penstock Bridge Site Over Knutson
Creek ................................................................................................................B 10
Photograph B 15 Elevation View of Proposed Penstock Bridge Site over Knutson
Creek ................................................................................................................B 11
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Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report xi
LIST OF TABLES
Table ES 1 Summary of Features for 200 kW Project............................................................... i
Table ES 2 Summary of Project Performance and Economics..................................................ii
Table 2 1 Estimated Community Energy Usage by Fuel Type and Purpose...........................8
Table 2 2 Existing Utility Generation Equipment ...................................................................9
Table 2 3 Recent Electric System Statistics ..........................................................................11
Table 2 4 Historic Population Data.......................................................................................13
Table 2 5 Local Demographics..............................................................................................13
Table 2 6 Comparative Median Household Incomes ...........................................................14
Table 2 7 Pedro Bay Building Inventory ...............................................................................14
Table 3 1 Technical Summary of Recommended Project.....................................................20
Table 4 1 Estimate of Total Installed Cost for Recommended Project (200 kW).................27
Table 4 2 Base Case Assumptions Used for Economic Analysis...........................................28
Table 4 3 Summary of Economic Data for Recommended Project......................................29
Table 4 4 Estimated PBVC Electric Rates with Recommended Project................................30
Table 4 5 Sensitivity Analysis Results (Debt Financed Project)............................................32
Table C 1 Summary of Hydrology Data for Knutson Creek.....................................................2
Table C 2 Flow Measurements at Knutson Creek and Tributaries.........................................3
Table D 1 Maximum Probable Flood at Knutson Creek..........................................................2
Table E 1 Areas of Knutson Creek Subbasins ......................................................................... 4
Table G 1 Cost Estimate for Recommended Project............................................................... 2
Table G 2 Economic Analysis of Recommended Project ........................................................ 3
Table G 3 Estimated Electric Rates with the Recommended Project.....................................8
Table H 1 Generation Dispatch Model Variables, Inputs, and Outputs..................................3
Table H 2 Actual and Modeled Electric Demand....................................................................4
Table H 3 Expected Range of Annual Performance for Recommended Project ....................7
Table H 4 Range of Project Design Parameters Considered and Recommended
Values...................................................................................................................... 8
Table H 5 Economic Evaluation of Hydro Project Configurations.........................................10
Table H 6 Heating Loads for Community Buildings and Homes...........................................11
Table H 7 Impacts of In Stream Flow Reservations on Hydro Performance........................12
Table H 8 Annual Performance of Recommended Project under Load Growth Cases........13
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ACRONYMS AND TERMINOLOGY
F degrees Fahrenheit
ABC Alaska Biological Consulting
ADCCED Alaska Department of Commerce, Community, and Economic Development
ADEC Alaska Department of Environmental Conservation
ADF&G Alaska Department of Fish and Game
ADNR Alaska Department of Natural Resources
AEA Alaska Energy Authority
AEE Alaska Energy and Engineering, Inc.
ATV all terrain vehicle
AS Alaska Statute
BBNC Bristol Bay Native Corporation, Inc.
BCR benefit cost ratio
btu British thermal unit
C.E. Civil Engineer
cfs cubic feet per second
coanda effect
The tendency of a moving fluid to stay attached to a smoothly convex solid
obstruction. A common example is the way a stream of water, as from a faucet,
will wrap around a cylindrical object held under the faucet (such as the barrel of
a drinking glass).
DCRA Division of Community and Regional Affairs (organized under ADCCED).
CPCN Certificate of Public Convenience and Necessity
discharge A synonym for stream flow. Flow and discharge are used interchangeably in this
report.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report vii
EA environmental attributes. The term environmental attributesis used by the
utility industry to describe the desirable aspects of electricity that are generated
from environmentally benign and/or renewable sources. Environmental
attributes are tracked, marketed, bought, and sold separately from the physical
energy. Separating the environmental attributes from the physical energy allows
customers or ratepayers to elect to buy sustainable or greenenergy even if it is
physically unavailable from their electric utility.
excess power, energy, electricity
Electricity generated by the hydro project in excess of the utilitys current load.
Excess energy can be directed to one or more interruptible loads (such as electric
heat) and may or may not have economic value depending on when it is
available and how it is used. At times when there is no beneficial use for excess
energy, water flow into the turbine can be reduced so that no excess energy is
generated.
FERC Federal Energy Regulatory Commission
ft foot, feet
GDM generation dispatch model. A model used to evaluate the performance and
output of proposed electric generation configurations (diesel and hydro).
HDPE high density polyethylene
in. inch, inches
interruptible power, energy, electricity, load, demand
Electricity that is generated by the hydro generator(s) in excess of system
demand (see excess power) and delivered to customers on a special interruptible
basis. Utility generation and delivery of interruptible electricity starts and stops
without notice based on water availability and other criteria. Interruptible
energy is also called dispatchable energyin some documents.
interruptible electric heating service
A special metered electric service that provides energy for space heating, water
heating, or similar purposes. Electricity is made available to the service only
when there is excess hydro (or other low cost) electricity generation capacity
available. The service is automatically turned off by the utility at times when
utility demand is high enough to require operation of more expensive
generators. Because the service is interruptible without notice, it is only suitable
for certain uses, and any important uses require a backup system. Space heating
and water heating are common uses because a buildings existing systems can
serve as backup at modest or no cost. The interruptible system can take many
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forms, and can be integrated with a buildings existing mechanical systems (an
electric boiler installed before an oil fired boiler, for example), or as an
independent supplemental system (an electric baseboard heater installed in a
building with an existing Toyo stove, for example).
ISER Institute of Social and Economic Research (University of Alaska Anchorage)
ISFR in stream flow reservation. A minimum amount of flow that must be left in a
river or stream during all or certain times of the year.
kV kilovolt, or 1,000 volts
kVA kilovolt ampere
kW kilowatt, or 1,000 watts. One kW is the power consumed by ten 100 watt
incandescent light bulbs.
kWh kilowatt hour. The quantity of energy equal to one kilowatt (kW) expended for
one hour.
LFC liquidtite flexible conduit
LFMC liquidtite flexible metal conduit
mi mile, miles
NAD North American Datum
NREL National Renewable Energy Laboratory
O&M operations and maintenance
OMR&R operating, maintenance, repair, and replacement
PBC Pedro Bay Corporation, Inc.
PBVC Pedro Bay Village Council
PCE Power Cost Equalization (program)
P.E. Professional Engineer
Pedro Bay May refer to the village or the water body on Lake Iliamna, but generally refers
to the village in this report.
Polarconsult Polarconsult Alaska, Inc.
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November 2013 Final Report ix
prime power, energy, electricity, load, demand
A use of electricity that utility customers expect to be supplied at their
convenience, as in turning on a light or television. The utility is responsible for
taking all reasonable measures to supply sufficient energy into the utility grid to
meet all instantaneous prime demand of its customers. Prime electricity can be
contrasted with excess or interruptible electricity, which is generated by the
utility only when conditions are favorable, and can be interrupted by the utility
without notice.
PTT pressure and temperature transducer
PVC polyvinyl chloride
RM river mile
rpm revolutions per minute
SDR standard dimension ratio
space heating Heating of buildings. May also include water heating for domestic use,
depending on the specific context and application.
USACE U.S. Army Corps of Engineers
USGS U.S. Geological Survey
V volt
VPSO Village Public Safety Office / Officer
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Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report 1
1.0 INTRODUCTION
1.1 PROJECT AUTHORIZATION AND PURPOSE
In July 2010, the Pedro Bay Village Council (PBVC) hired Polarconsult Alaska, Inc. (Polarconsult)
to perform a feasibility study for a hydroelectric project on Knutson Creek. This report presents
the findings of the feasibility study and makes recommendations for further action based upon
the feasibility study findings.
A draft of this report was issued in November 2012 for review and comment. This final version
of the report incorporates comments received from the community and from the Alaska Energy
Authority through October 2013. Comments and major revisions made to the draft report are
summarized in Appendix I.
1.2 SUMMARY OF FINDINGS
The feasibility analysis described in this report finds that a run of river hydroelectric project on
Knutson Creek is feasible from technical, regulatory, and economic standpoints. An installed
capacity of approximately 100 to 250 kilowatts (kW) is best suited to the villages long term
energy needs. The recommended project can lower energy costs for Pedro Bay Village by up to
92% from current electric utility rates, depending on permit conditions, project financing, final
installed cost, and utilization of excess energy through interruptible electric heating services.
The economic analysis identified a 200 kW hydroelectric project as the most cost effective
configuration. A 200 kilowatt (kW) project will have a design flow of 18.25 cubic feet per
second (cfs), which is conveyed from a diversion and intake structure at river mile (RM) 2.59
down to a hydro powerhouse near RM 1.25 via a 26 inch diameter, 7,080 foot long high
density polyethylene (HDPE) penstock. Total gross head is 223.8 feet, and net operating head
at full flow is 206.5 feet. The hydro powerhouse is connected to the villages existing electric
distribution system via a 9,900 foot long buried power cable. The project includes 16,400
linear feet of new roads and trails. The project location is shown on Figure A 1, and the project
layout is shown on Figure A 2.
The recommended project is estimated to supply 95.6% of Pedro Bays current annual electric
demand, displacing 16,600 gallons of fuel annually. At a fuel cost of $5.83 per gallon, the
project is estimated to reduce utility fuel expenses by $96,778 annually. The recommended
project can also supply approximately 86% of the annual space heating needs of seven
community buildings, and approximately 56% of the annual space heating needs of the
communitys 33 homes, through interruptible electric heating systems. This application of
excess hydro output will displace an additional approximately 24,200 gallons of heating fuel
annually, saving the community an additional $156,500 per year. Interruptible heating
applications use 73% of the total energy output of the recommended project, with normal
utility demand using another 12%. At existing utility demand levels, 15% of the projects total
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energy output is calculated to remain unused and available for future growth. In order to
realize the full benefits of a hydro project on Knutson Creek, it is necessary for the village to
refit its community buildings and homes with interruptible electric heating systems.
An economic analysis of the project indicates it has a benefit cost ratio (BCR) of between 1.18
and 2.00 compared to continued reliance on the diesel power plant. This analysis assumes
utilization of excess hydro energy to provide interruptible heating systems for community
buildings and homes. Further discussion on project costs and economic analysis may be found
in Section 4.0 and Appendices G and H.
1.3 PROJECT EVALUATION PROCESS
Hydroelectric development options for Knutson Creek were evaluated using an iterative
process to arrive at the recommended project. Initially, resource data for Knutson Creek were
collected and analyzed along with the communitys electric demand profile to identify several
initial project configurations for further evaluation. The resource data included stream
hydrology, site topography, and related information. Environmental and regulatory factors
were also considered in developing candidate project configurations. Data from the electric
utility were collected and analyzed to develop a model of the communitys electric demand
profile. These data were input to a generation dispatch model (GDM) to determine how much
prime electricity and interruptible electricity each project configuration would produce.
The electrical output for each project alternative was integrated with economic data comprised
of fuel costs, construction costs, operations and maintenance (O&M) costs, and financing
options to develop a BCR. The recommended project supplies the highest percentage of current
and projected future electrical demand (considering both prime demand and interruptible
energy services) while maintaining an acceptable BCR and satisfying expected environmental
constraints. This evaluation process is represented graphically on Figure 1 1.
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November 2013 Final Report 3
Figure 1 1 Feasibility Evaluation Process Flowchart
GENERATION DISPATCH MODEL
Projects how much electricity is generated by
diesel and hydro for each project configuration.
Also projects excess energy generation.
ELECTRICAL LOADS
PCE & utility reports
Utility load profile
PROJECT RESOURCE DATA
Knutson Creek hydrology
Site topography
Fisheries data
LOAD PROFILE
Prime power demand
Potential interruptible energy loads
ELIGIBLE HEATING LOAD
Building inventory
Climate data
HYDROLOGY
Flood magnitude
Flow duration, timing and frequency
ECONOMIC EVALUATION
COMMUNITY NEEDS MET?
BENEFIT/COST RATIO?
ECONOMIC DATA
Diesel fuel cost
Excess energy value
Financing plan
RECOMMENDED PROJECT
PROJECT COST DATA
Design and permitting costs
Project design approach
Construction methods
Construction cost estimate
Operation and maintenance costs
SURVEYS
Gross head
Pipe, power, access
distances and
alignments
Property ownership
ENVIRONMENTAL &
REGULATORY CONSTRAINTS
Aquatic resources
Aesthetics
Special restrictions
GEOTECHNICAL
ASSESSMENTS
Stream diversion sites
Civil infrastructure
Project alignments
COMMUNITY REVIEW AND
FEEDBACK
RESULTEVALUATION ANALYSISINPUT DATA
ITERATIONS TO
IMPROVE
PROJECT
PROPOSED PROJECT
CONFIGURATION
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1.4 CURRENT AND PREVIOUS STUDIES
1.4.1 1981 Regional Reconnaissance Study
In 1981, the U.S. Army Corps of Engineers (USACE) performed a regional study of potential
hydroelectric resources in southwest Alaska. As part of this study, the USACE looked at two
potential 100 kW run of river projects in the area of Pedro Bay Village, one at Knutson Creek
and the other at Canyon Creek. Ultimately, the USACE concluded that neither project was
economical. Since then, however, improvements in technology and changes in the price and
usage patterns of other energy sources have made the prospect of developing a hydroelectric
project near Pedro Bay far more favorable.
1.4.2 2009 Regional Reconnaissance Study
In 2009, Polarconsult performed a reconnaissance study of potential hydropower resources in
the Pedro Bay area. This study looked at six potential sites: Knutson Creek, its three main
tributaries, Dumbbell Lake/Russian Creek, and Cottonwood Creek. Four of those sites, the main
fork of Knutson Creek and its three major tributaries, were selected as potentially viable sites
for hydropower development. The PBVC ultimately selected the main fork of Knutson Creek as
its preferred development site for continued investigation.
1.4.3 Current Feasibility Study
Between 2010 and 2012, Polarconsult engineers completed several trips to Pedro Bay to
conduct feasibility level field investigations of the Knutson Creek site. Polarconsult personnel
were assisted by Mr. Ben Foss, the community's manager for this project,or other community
representatives on most field investigations. Field trips and activities completed are
summarized below.
October 10 15, 2010 (Joel Groves, P.E., Gary Paulus, C.E.)
Installed a stream gauging station on Knutson Creek at RM 2.04 (lower station).
Measured discharge on Knutson Creek twice and on tributary R1
2 once.
Performed a reconnaissance of Knutson Creek to identify prospective access routes,
intake sites, and penstock routes.
Completed initial topographic surveys of the project area to determine the available
elevation drop for the project.
2 This report references the unnamed major tributaries of Knutson Creek by which side of the creek they are on
looking upstream (Lfor left,Rfor right) and their numerical order of occurrence ascending the creek from
its mouth on Lake Iliamna. Note that this left/rightconvention is opposite the facing downstream
convention customarily used in the natural sciences. This standard was adopted to facilitate visualization of
these tributaries as viewed from Pedro Bay Village, as well as on maps oriented with north up.
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February 4, 2011 (Gary Paulus, C.E.)
Measured discharge on Knutson Creek and downloaded lower stream gauging station
data.
April 4, 2011 (Joel Groves, P.E.)
Measured discharge on Knutson Creek and downloaded lower stream gauging station
data.
May 4 5, 2011 (Joel Groves, P.E.)
Measured discharge on Knutson Creek and downloaded lower stream gauging station
data.
Completed additional topographic surveys of the project area and evaluated
powerhouse sites along the east and west banks of Knutson Creek.
November 15, 2011 (Gary Paulus, C.E.)
Installed a second stream gauging station on Knutson Creek near the mouth of tributary
L1 at RM 2.10 (upper station).
Measured discharge on Knutson Creek and downloaded lower stream gauging station
data.
April 19, 2012 (Joel Groves, P.E.; Mike Dahl, P.E.)
Measured discharge on Knutson Creek and downloaded lower stream gauging station
data.
July 20, 2012 (Joel Groves, P.E.)
Attempted to download upper stream gauging station data, but discovered it was
destroyed. Attempted to measure discharge on Knutson Creek, but was unable to do so
due to unsafe conditions (high flow and velocity).
August 23 25, 2012 (Bruce Barrett, Fisheries Biologist, and Joel Groves, P.E.)
Mr. Barrett conducted fish surveys of the project reach of Knutson Creek to assess fish
habitat, fish presence, and habitat utilization.
Mr. Groves installed new gauge hardware at the upper gauging station and reinforced
the station installation to reduce the likelihood of future hardware loss. Attempted to
measure discharge on Knutson Creek, but was unable to do so due to unsafe conditions
(high flow and velocity).
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2.0 COMMUNITY PROFILE
2.1 COMMUNITY OVERVIEW
Pedro Bay Village is an unincorporated community located at the east end of Iliamna Lake on
the Alaska Peninsula, within Township 4 South, Range 28 West of the Seward Meridian. Its
geographic coordinates are 59 47 14north and 154 6 22west. The community and project
site are both located within U.S. Geological Survey (USGS) quadrangle maps Iliamna D 3 and D
4. The village is approximately 175 miles southwest of Anchorage and 90 miles west of Homer.
The community can be accessed by air or water, and barge service is seasonally available from
Naknek via the Kvichak River and from Homer via Williamsport and the Pile Bay Road. Pedro
Bay is located in the Iliamna Recording District and the Lake and Peninsula Borough School
District.
Pedro Bay is located in a transitional climactic zone. Average temperatures fall between 42
degrees Fahrenheit (F) and 62 F in the summer and 6 F and 30 F in the winter. Extreme
temperatures range from 50 F to 84 F. Average annual precipitation is 35 inches, comprised
of 26 inches of rainfall and 64 inches of snowfall.
The population of Pedro Bay is approximately 42. Most residents have seasonal employment in
the Bristol Bay fishery or in the local tourism industry. The majority of residents also depend
upon fish and game (e.g., trout, salmon, bear, and moose) obtained through subsistence
hunting and fishing activities. Pedro Bay has a federally recognized Alaska Native tribe,
organized as the PBVC.
Most of the houses in Pedro Bay are fully plumbed and utilize individual wells and septic
systems although Pedro Bay does maintain a community washeteria and some residents still
rely on honey buckets for waste management. Honey bucket hauling services and septic
pumping services are provided by the PBVC, which also maintains the landfill and provides
electrical service. Community services available in Pedro Bay include a school and a health
clinic, although the school was closed in fall of 2011 due to low enrollment.
3
2.2 EXISTING ENERGY SYSTEM
2.2.1 Community Energy Overview
Pedro Bay has an isolated electrical system with no transmission interconnections to other
communities. Pedro Bay relies 100% on diesel generation for electricity. Diesel and other
petroleum fuels are delivered by barge or airplane several times annually. Other local energy
usage includes diesel and gasoline fuels for transportation, wood and fuel oil for space and
3 All information was complied from the ADCCED community profile for Pedro Bay Village.
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water heating, and propane gas for cooking and heating. Table 2 1 lists estimated annual fuel
consumption by type and purpose.
Table 2 1 Estimated Community Energy Usage by Fuel Type and Purpose
Purpose (1)Fuel Estimated Annual Quantity Estimated Annual Cost
(2)
Electric Diesel 22,000 gallons $118,800
Heating (3)Diesel/Fuel Oil 20,000 gallons $128,000
Heating (3)Wood 50 80 cords NA
Transportation Diesel/Gasoline 8,000 gallons $55,200
Total Hydrocarbon Fuels 50,000 gallons $302,000
NOTES:
(1) Electric system data from PCE program and utility reports. Other fuel usage estimates based on the Pedro Bay Bulk Fuel
Consolidation and Upgrade Concept Design Report (Alaska Energy and Engineering, Inc. [AEE], 2003) and energy data
from the Alaska Energy Authoritys (AEAs) 2010 Alaska Energy Plan Community Database,
http://www.akenergyauthority.org/alaska energy plan.html
(2) Based on $5.40 per gallon for power plant fuel, $6.40 per gallon for heating fuel, $6.90 per gallon for transportation fuel.
(2012$).
(3) 25% of building heating needs is assumed to be met by wood and 75% by fuel oil. Wood is assumed to be locally
harvested at no direct expense (only transportation fuel, labor, etc.).
2.2.2 Electric Utility Organization
Pedro Bays electric service is provided by the PBVC pursuant to Certificate of Public
Convenience and Necessity (CPCN) No. 662, which allows the PBVC to operate a public utility
for providing electric services in and around Pedro Bay Village. The CPCN was issued in 2002 by
the Regulatory Commission of Alaska, which has exempted the PBVC from rate regulation
pursuant to the public interest exception included in Alaska Statute (AS) 42.05.711.
4 PBVC
participates in the states Power Cost Equalization (PCE) program. This program subsidizes
electrical rates for residences and community facilities served by eligible rural Alaska utilities.
2.2.3 Generation System
Pedro Bay's diesel power plant is located at the school. The power plant has one 95 kW diesel
generator and two 62 kW diesel generators. The school has a separate 62 kW generator for
emergency power. This fourth generator is not configured to feed the village power grid. The
power plant switchgear is fully automatic with paralleling capability and uses a programmable
logic controller to match the generators to system load. AEA upgraded the power plant
switchgear in 2012.
5 The plant generates at 480 V single phase, which is stepped up to 7,200 V
for distribution with a 100 kilovolt amp (kVA) transformer. The 95 kW generator set was
installed new in 2000, and the three 62 kW generator sets were installed new in 2001. Installed
generation equipment is listed in Table 2 2. The diesel power plant is fitted with a waste heat
4 The certificate and exemption were grantedin RCA docket U 89 005, Order #4.
5 Switchgear upgrade design drawings dated January 19, 2012 (AEA, 2012c) and undated switchgear redlines.
(AEA, 2012d).
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system that provides heat to the school.
6 AEA completed upgrades to the waste heat system in
2013.7
Table 2 2 Existing Utility Generation Equipment
No. Equipment
Prime Power
(kW)
Commissioned
Date
Total Hours
(November
2012)
Designated
Use
1 John Deere 6059 TFG01 Engine
Marathon Magnaplus Generator
95 kW 2000 NA Utility Peak
2 John Deere 4045 T150 Engine
Marathon Magnaplus Generator
62 kW 2001 37,000 Utility Base
3 John Deere 4045 T150 Engine
Marathon Magnaplus Generator
62 kW 2001 42,000 Utility Base
NA: not available.
2.2.4 Electrical Distribution System
Pedro Bays distribution system consists of a 7,200 volt (V) single phase buried cable system.
There is also a significant amount of submarine cable running under Lake Iliamna to several
sites in the vicinity of the village. There is a reactor installed on the system to compensate for
the capacitance of these cables and maintain an acceptable power factor on the electric
system.8
2.2.5 Planned Upgrades
No upgrades are planned for the diesel power plant, bulk fuel facility, or distribution system.
The two 62 kW gensets have high hours, and are in need of overhaul or replacement in the near
future.
2.2.6 Existing Load Profile
Total system electrical demand from 2003 to 2013 is presented on Figure 2 1 and in Table 2 3.
From 2003 to 2011, average wintertime demand was approximately 25 to 30 kW. Average
summer time demand from 2003 to 2011 ranged from 20 to 25 kW.
Since the school closed in late 2011, seasonal variation in demand has decreased and demand is
now generally constant at approximately 16 to 20 kW year round.
Total generation from 2009 to 2011 (approximately 256,500 kilowatt hours [kWh] per year)
was approximately 5% lower than the average generation from 2004 through 2008
6 Pedro Bay Power System Upgrade, Record Drawings, AEE, Inc., September 1, 2005.
7 Pedro Bay Heat Recovery Expansion Drawing Red Lines, AEE, Inc., September 21, 2013.
8 Record drawings dated September 2005 indicate this reactor was still present in Pedro Bay but was not
connected to the distribution system (AEE, 2005). Its current status is unknown.
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0
10
20
30
40
50
60
70
80
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Peak Monthly Generation (kW)
Average Monthly Generation (kW)
(approximately 269,000 kWh per year). This decrease is attributed to conservation efforts and
sacrifices made by Pedro Bay ratepayers in response to the 51% increase in the price of
electricity that was implemented in late 2008 due to increasing fuel costs.
Since the school closed in late 2011, total generation has decreased significantly, with year
over year declines of approximately 10% occurring in 2011, 2012, and 2013 (year to date).
Total generation in 2012 was approximately 204,000 kWh, and total generation in 2013 is
estimated to be 180,000 to 190,000 kWh.
Figure 2 1 Recent Monthly Peak and Average Power Generation
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final Report 11Table 23 Recent Electric System StatisticsParameter 2003(1)2004 2005 2006 2007 2008 2009 2010 2011 2012 2013(3)kWh Generated 102,314 249,083 295,974 272,211 264,939 262,759 256,409 256,677226,927(2)203,953 139,690kWh for Station Service(% of total generation)5,257(5.1%)10,411(4.2%)14,239(4.8%)14,474(5.3%)12,112(4.6%)12,217(4.6%)12,222(4.8%)12,299(4.8%)11,718(5.2%)10,793(5.3%)9,698(6.9%)kWh Sold 85,778 212,284 246,953 237,475 232,618 231,273 233,755 236,982200,942 174,562 116,412System Losses(1(sold + station service)/generated)11.02% 10.59% 11.75% 7.44% 7.63% 7.33% 4.07%2.88% 6.32% 9.12% 9.72%Fuel Used (gallons) 10,403 23,349 22,552 19,454 20,325 23,458 21,01821,673 19,514 20,583 14,035Generation Efficiency(kWh/gal)9.8 10.7 13.1 14.0 13.0 11.2 12.2 11.8 11.6 9.9 10.0Fuel Price (annual average) $2.24 $2.57 $2.74 $3.04 $5.06 $6.14 $4.60 $4.56 $5.23 $5.78 $5.91Total Fuel Expense $23,321 $60,121 $61,798 $59,181 $102,886 $144,133 $96,669 $98,880 $102,132 $118,974 $82,989Total Nonfuel Expense $18,870 $41,233 $47,015 $41,811 $38,664 $44,833 $44,696 $53,855 $52,248 $34,539 $27,487Total Utility Expense $42,190 $101,353 $108,814 $100,992 $141,550 $188,966 $141,365$152,735 $154,380 $153,513 $110,476Electric Cost per kWh $0.492 $0.477 $0.441 $0.425 $0.609 $0.817 $0.605 $0.645 $0.768 $0.879 $0.949Utility Rate ($/kWh) $0.600 $0.600 $0.600 $0.600 $0.600 $0.600 $0.910 $0.910 $0.910 $0.910 NAResidential Rate with PCE($/kWh, annual average)(4) (4) (4) (4) (4)$0.262(4)$0.424 $0.424 $0.466 $0.259 NANOTES:All data are compiled from monthly PCE program records provided by the AEA (2012).(1) Records for 2003 include July through December only.(2) Generation data for March 2011 are missing, and are estimated from kWh sales, powerhouse consumption, and line losses of 6.3%.(3) Records for 2013 include January through September only.(4) Older data not provided in the AEA database.kWh kilowatthourNA not available.
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2.2.7 Projected Future Load Profile
Community electrical demand is a function of population, electricity cost, and available income.
Commercial, industrial, and transient loads can also be major factors in total electrical demand.
In small Alaska villages with extremely high electric rates such as Pedro Bay Village, demand
often increases significantly in response to reduced electric rates. Reduced electric rates may
also encourage an increase in population over time, which can also cause an increase in
electrical demand.
The recommended 200 kW hydro project provides significant capacity for future load growth.
As prime utility demand grows, some of the interruptible energy that is proposed to be
dispatched to building heating loads would instead be dispatched to prime loads. Project
performance was evaluated for the following four load growth scenarios.
(1) 50% reduction in demand from current levels.
(2) Continuation of existing demand.
(3) 200% increase from current levels.
(4) 400% increase from current levels.
Under the different load growth scenarios, total project output remains relatively constant, and
the portion of the projects output that is used to supply prime demand varies. These load
growth scenarios are discussed in greater detail in Section H.4 of Appendix H.
2.2.8 Population
The population of Pedro Bay in 2010 was 42, and the estimated 2011 population was 47.
Historically, the population of Pedro Bay has fluctuated somewhat from decade to decade but
has always remained below 70 (Table 2 4). In the years for which population data are available,
Pedro Bays highest population figure was 65 in 1970. Its lowest population figure was 33 in
1980. Population has been relatively stable since 1990, at approximately 46 +/10%. Future
population in Pedro Bay is assumed to stay within the historic range and is expected to be
influenced by demographic trends (see Table 2 5) and local economic opportunities.
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Table 2 4 Historic Population Data
Year Population
1
1950 44
1960 53
1970 65
1980 33
1990 42
2000 50
2010 42
2011 47
2
2012 42
2
Future Projection 30 to 70
NOTES:
(1) Population data from decennial U.S. Census Bureau reports.
(2) 2011 population is estimated by the DCRA.
Table 2 5 Local Demographics
Age Cohort (2010) Cohort Population
0 to 9 4
10 to 19 9
20 to 29 4
30 to 39 4
40 to 49 5
50 to 59 8
60 to 69 3
70 to 79 2
80+ 3
Total Population (2010) 42
Median Age (2010) 40
NOTE:
Data from 2010 Census.
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2.2.9 Income
Median household incomes for Pedro Bay, Alaska, and the United States are summarized in
Table 2 6. In 2010, household income in Pedro Bay was approximately 68% of household
income in Alaska.
Table 2 6 Comparative Median Household Incomes
Population Group 1990 2000 2010
Pedro Bay Median Household Income as percentage
of Alaska Median Household Income
NA NA 68%
Pedro Bay NA NA $40,750
1
Alaska $65,556
2 $69,021 2 $59,672 2
United States $49,950
2 $54,841 2 $50,831 2
NOTES:
(1) 2005 2009 5 Year estimate from Alaska Department of Labor and Workforce Development. American Community
Survey. Web http://labor.alaska.gov/research/census/
(2) Data from U.S. Census Bureau, Table H 8, 2011 version. Amounts are in 2011 dollars.
NA: Not Available.
2.2.10 Public Buildings and Housing Units
Major buildings in Pedro Bay Village are summarized in Table 2 7. The villages building
inventory is a potential market for excess energy from the hydro project by adding interruptible
electric heating services to these buildings to offset fuel used by their existing heating systems.
Table 2 7 Pedro Bay Building Inventory
Type of Building Estimated Quantity
Housing Units 33
(1)
Village Council Building (Meeting Hall, Washeteria) 1
Village Public Safety Officer (VPSO) Office 1
Church 1
School 2
Airport maintenance building 1
NOTE:
(1) Number of housing units recorded in the 2010 Census (U.S. Census Bureau, 2012). Pedro Bay Village has 33 housing units,
of which 19 are occupied, 13 are seasonally occupied, and 1 is vacant. All housing units are assumed to be detached
single family dwellings.
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$0.00
$0.10
$0.20
$0.30
$0.40
$0.50
$0.60
$0.70
$0.80
$0.90
$1.00
$1.10
$1.20
$1.30
$1.40
$1.50
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Non-Fuel Cost ($ per kWh)
Fuel Cost ($ per kWh)
Total Utility Costs ($ per kWh)
Retail Electric Rate ($ per kWh)
2.2.11 Energy Market
Energy from a local hydroelectric project will be fed into the Pedro Bay Village electric system
to offset the need for diesel power generation. In addition, the hydroelectric project will often
generate energy in excess of electrical demand. It is recommended that this excess energy be
made available on an interruptible basis to offset other local energy consumption for space and
water heating.
Fuel prices in Pedro Bay have increased significantly in recent years. The average price of fuel
was $2.68 per gallon in 2003 2006, $4.27 per gallon from 2007 2010, and $5.62 per gallon from
2011 to 2013. This is an increase of 30% in the past 3 years, and 210% within the past decade.
The fuel, non fuel and total electricity costs in Pedro Bay are presented on Figure 2 2.
Figure 2 2 Recent Electric Utility and Electricity Costs
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3.0 RECOMMENDED PROJECT
3.1 RESOURCE DESCRIPTION
The resource considered in this study is Knutson Creek, located immediately west of Pedro Bay
Village, and shown on Figures A 1 and A 2. Knutson Creek is an approximately 7.5 mile long
creek that drains a southwest facing basin measuring 37.11 square miles in area. The basin is a
typical U shaped post glacial mountain valley aligned on a northeast southwest axis and
measuring approximately 10 miles long by 3 to 4 miles wide. It is ringed by mountains to the
east, north, and northwest that rise to elevations of approximately 2,200 to 4,600 feet, with the
highest peaks along the northeast perimeter of the basin. The lowest elevation in the basin, at
the creeks outlet to Lake Iliamna, is at an elevation of approximately 50 feet. Lake Clark
National Park and Preserve abuts the northern drainage divide of the Knutson Creek basin.
Approximately 40% of the basin is vegetated. The lower valley floor and lower mountain slopes
are vegetated by a mature mixed conifer and deciduous forest typical of southcentral Alaska.
Dominant species include white and black spruce, birch, and cottonwood. Willow and alder
bushes become the dominant species above approximately 500 to 1,000 feet, eventually giving
way to open tundra above elevations of approximately 1,500 to 2,500 feet.
Knutson Creeks headwaters are two alpine streams located at the northeast end of the basin.
From the confluence of these streams at approximately RM 7.5, Knutson Creek runs down the
center of the valley confined within an incised notch that is typically 300 to 1,000 feet wide and
50 to 100 feet deep. In a few locations, Knutson Creek has carved a canyon with widths
narrowing to 150 feet. The creek generally descends at a grade of 3% to 4% from RM 7.5 down
to approximately RM 1.5. At this point, the creek leaves its confined corridor and emerges onto
an active alluvial cone for the remaining 1.5 miles to Lake Iliamna. The grade along this lower
reach is approximately 1% to 2%. Based on surface observations, bedrock is at or near the
surface along the reach from RM 1.5 to RM 7.5. No bedrock is visible in the alluvial cone below
RM 1.5.
Knutson Creek is listed by the Alaska Department of Fish and Game (ADF&G) as anadromous
fish habitat.
9 Field surveys completed in August 2012 for this project by Alaska Biological
Consulting confirmed the presence of low numbers (~100 fish) of sockeye salmon in spawning
condition in the proposed bypass reach between RM 1.25 and RM 2.10, and the presence of
resident mountain Dolly Varden throughout the proposed bypass reach from RM 1.25 up to RM
2.70. Fish surveys were not completed beyond these limits, but similarity of habitat conditions
9 Knutson Creek is listed in the Atlas and Catalog of Waters Important to the Spawning, Rearing, and Migration
of Anadromous Fishes,maintained by the Alaska Department of Fish and Game.
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suggest Dolly Varden occur farther up and downstream. Based on the August 2012 survey
results, anadromous habitat in the bypass reach is considered marginal.
Negotiating reasonable fish habitat permit conditions associated with this marginal habitat will
be very important to realizing the full benefits of this project. Accordingly, Polarconsult
engaged with ADF&G early in the feasibility study, meeting with ADF&G staff in September
2010 and June 2011 to discuss the project, likely fisheries impacts and appropriate mitigation
measures. Alaska Biological Consulting consulted with ADF&G staff in 2012 to discuss the
design of the fisheries survey and to understand the limiting resource conditions for sockeye in
the project area. The fisheries report was provided to ADF&G in October of 2012.
The in stream flow reservations and associated project design elements presented in this
report are based on these consultations with ADF&G. Fish habitat issues and the impacts of
habitat permit conditions are discussed in Sections E.2 and H.3 of the appendices, respectively.
Meeting records from the September 2010 and June 2011 meetings with ADF&G are included in
Appendix E as Attachments E 1 and E 2 respectively. The Fisheries Surveys Report completed
by Alaska Biological Consulting is included as Attachment E 3.
A stream gauging station has been measuring stream flow on Knutson Creek at RM 2.04 since
October 2010. Based on station data, Knutson Creek at the proposed diversion site has a mean
annual flow of approximately 105 cubic feet per second (cfs), with an annual low flow of 7 to 20
cfs occurring in March and April, and seasonal high flows of approximately 1,000+ cfs. Detailed
hydrology and gauging station information is presented in Appendix C and Attachment C 1.
Technical aspects of Knutson Creek and the project area pertinent to the proposed project are
discussed in Appendix D.
3.2 OVERVIEW OF RECOMMENDED PROJECT
Polarconsult evaluated several run of river project configurations on Knutson Creek ranging in
installed capacity from 100 to 1,000 kW. All of these configurations have the same diversion
and powerhouse locations, as these sites are well defined by the configuration of Knutson
Creeks tributaries and the topography of the area. Of these configurations, a project capacity
of approximately 100 to 250 kW is best suited to Pedro Bays long term needs.
The economic analysis presented in Section 4 and Appendix G of this report identify a 200 kW
project as the most economic configuration, and the technical description presented in this
section is for a project of this size. The actual installed capacity of the project, likely within the
100 to 250 kW range, should be determined once permit conditions are known and project
designs and cost estimates are more advanced.
The recommended project is a run of river hydroelectric project on Knutson Creek with an
intake at RM 2.59 and a powerhouse near RM 1.25, returning water to Knutson Creek at RM
1.10 via a 1,400 foot long tailrace channel. The recommended project has a 7,080 foot long,
26 inch diameter buried HDPE penstock, developing total gross head of 223.8 feet and net
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head at full flow of 206.5 feet. The recommended design flow is 18.25 cfs for an installed
generating capacity of 200 kW. Technical details of the recommended project are listed in
Table 3 1. Each major component is discussed in greater detail in Section 3.4 and shown on the
conceptual design drawings in Appendix K.
The hydrology, topography, and geology of the project site clearly define the siting, routing, and
general configuration of the recommended projects major features. Design details of the
features as shown on the conceptual design drawings are subject to refinement as permit
conditions become known and additional site information is collected in the permitting and
design phase of project development.
The optimaldesign flow and installed capacity of the project are not clearly defined by site
conditions. Knutson Creek has sufficient flow to support a significantly larger run of river hydro
project than the current village of Pedro Bay needs.
10 Undersizing the hydro project would
sacrifice an opportunity to support future growth of the community at modest incremental
capital expense. Oversizing the hydro project would result in unnecessary capital expense with
no benefit to the community and could also burden the community with increased O&M
expenses over the life of the project. The challenge in selecting the project capacity is to weigh
these considerations evenly to arrive at an optimal project capacity. Polarconsults analysis,
presented in Section H.2 of Appendix H, identifies a 200 kW project as the most economic size.
This analysis should be revisited once project permit conditions have been finalized and designs
and capital cost estimates are more refined.
With the recommended project, Pedro Bay Village has an opportunity to displace a significant
portion of its heating fuel purchases by using hydro project capacity to supply energy to
community buildings and homes for heating purposes on an interruptible basis. The
recommended project includes provisions to supply approximately 85% of the space heating
needs of community buildings and approximately 53% of the space heating needs of homes.
This will require refitting these buildings with additional electric services that can be
interrupted when needed to prioritize hydro generation capacity toward meeting electric utility
needs. This will avoid unnecessary operation of the diesel power plant.
Figure 3 1 presents hydro energy generated by the recommended project throughout a typical
year (2007) and shows how that energy is dispatched to meet utility system demand and
various interruptible electric heating services in the community.
10 If a market existed for the full output of a run of river project on Knutson Creek, the optimal installed capacity
on a strictly economic basis (lowest $ per kWh for energy) is estimated at 800 to 1,200 kW.
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Table 3 1 Technical Summary of Recommended Project
PROJECT FEATURES VALUE
Access Trails 16,400 feet
Primary Power Lines 9,900 feet
Communications Lines 18,000 feet
Basin Area Above Diversion Site (square miles) 29.17 square miles
Mean Annual Flow (cfs) 108 cfs
Minimum Flow (cfs)
13.3 cfs (average annual minimum flow)
6.8 cfs (extreme minimum flow)
Plant Design Flow (cfs) 18 cfs
Assumed In Stream Flow Reservation (ISFR) 6.6 cfs
Intake Headwater Elevation (ft) 398.5 feet
Powerhouse Finished Floor Elevation (ft) 178.0 feet
Normal Tailwater Elevation (ft) 174.7 feet
Gross Head (ft) 223.8 feet
Pipeline Length (ft)/Diameter (in) 7,080 feet of 26 inch HDPE
Net Head at Full Flow (ft) 206.5 feet
Type of Turbine Single Crossflow Turbine
(1)
Minimum Power Generation (kW) 50 kW
(1)
Installed Capacity (kW) 200 kW
Plant Capacity Factor
(2)85.8%
Dam/Diversion Height (ft) 7 feet
Available Storage Volume (ac ft) none
ESTIMATED ANNUAL ENERGY GENERATION CHARACTERISTICS WITH RECOMMENDED HYDRO PROJECT
Total Existing Annual PBVC Load (kWh) 182,200 kWh
PBVC Utility Demand Supplied by Diesel (kWh) 8,100 kWh (4.4%)
PBVC Utility Demand Supplied by Hydro (kWh) 174,100 kWh (95.6%)
Total Annual Hydro Energy Generation (kWh) 1,503,700 kWh
Hydro Output used to Supply Existing PBVC Load (kWh) 174,100 kWh
Gross Excess Energy Available from Hydro (kWh)
(3)1,329,600 kWh
Gross Excess Hydro Energy Dispatched to
Community Buildings for Heating Applications (kWh)
(4)603,900 kWh
Gross Excess Hydro Energy Dispatched to
Homes for Heating Applications (kWh)
(5)486,400 kWh
Remaining Excess Energy Available from Hydro (kWh) 239,300 kWh
NOTES:
(1) The turbine configuration considered in this study is a single crossflow turbine, which typically has a minimum operating
threshold of 25% of rated output. See Section H.1.1 for discussion of alternate turbine configurations that may warrant
consideration for this project.
(2) The amount of energy the project can produce with available water divided by the amount of energy the project could
produce operating at 100% output year round. This is calculated with an assumed ISFR of 6.6 cfs.
(3)Gross excess energymeans this is the energy generated at the hydro powerhouse, before system losses are subtracted.
(4) Includes 141,000 kWh dispatched to the school to make up for the loss of waste heat from the diesel power plant.
(5) See Appendix H for a full discussion of interruptible electric heating service analysis.
cfs cubic feet per second HDPE high density polyethylene kWh kilowatt hour PBVC Pedro Bay Village Council
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final Report 21Daily Energy Demand and Supply(Average Daily kW)Figure 31 Typical Hydro Energy Output and Utilization, Recommended Project
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3.3 DESCRIPTION OF PROJECT FEATURES
The descriptions of project features in this section are conceptual and are based upon review of
site conditions, construction costs, logistical considerations, long term maintenance and
operational considerations, and related factors. In many cases, there are multiple viable
construction methods or design decisions that can be used. In these cases, decisions will be
made in the design and permitting phase of the project as additional information on
environmental, regulatory, and technical constraints becomes available.
The recommended project has a design flow of 18.25 cfs and an installed capacity of 200 kW.
Conceptual design drawings for the recommended project are included in Appendix K of this
report.
3.3.1 Transmission Line
There are two logical routes and connection points for the hydro project to feed into the
existing Pedro Bay Village electric distribution system. The preferred route is an approximately
9,900 foot long route running from the hydro powerhouse along the hydro access road to the
airport access road, then following the airport access road east to the PBVC building,
connecting with the existing distribution system at transformer TX 2 near the PBVC building.
The alternate route is an approximately 8,700 foot long route running along the hydro access
road, then west along the airport access road to connect with the existing distribution system
at transformer TX 20 at the airport maintenance building.
11
While the preferred route is longer than the alternate route, it provides a more direct
connection to the existing diesel powerhouse, which will result in increased system reliability.
It also runs by approximately 4,000 feet of potentially developable land along the airport access
road and would help facilitate future development of this property. The preferred route is used
for all economic and other analyses in this study.
The transmission line can be either underground or overhead. The villages existing 7,200V
distribution system is entirely underground, and the terrain along the preferred transmission
line route appears suitable for installation of an underground line. The cable can be direct
buried or buried in duct.
3.3.2 Controls and System Integration
The hydro project will have a dedicated communications circuit running between the hydro and
diesel powerhouses to coordinate operations and allow remote monitoring and operation of
the hydro project. There will also be a dedicated communications circuit between the hydro
powerhouse and hydro intake. This circuit will provide the hydro controls information about
11 Transformer numbers taken from the Pedro Bay Distribution Upgrade Drawings (ADCCED, 1995).
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the intake status, including availability of water for power generation. It will also support
remote operation of gates and apparatus at the intake, as well as remote monitoring of the
intake.
The hydroelectric generator will be a single phase 480 V synchronous machine. It will normally
be the sole generation source for the village but will also be capable of paralleling with the
diesel generators when needed. A pad mounted transformer will be located outside the hydro
powerhouse to step the voltage up to 7,200 V to connect with the existing electric distribution
system. A manual disconnect and fuse will be located at the hydro powerhouse, enabling the
hydro powerhouse to be isolated from the distribution system for maintenance and repair.
The switchgear at both powerhouses will be modified to integrate operations. Diesel
switchgear was upgraded by AEA in 2012 and 2013. Under normal operation, the hydro plant
will carry the full system load and the diesel engines will be turned off in standby mode. As
system load approaches the available capacity of the hydro, the switchgear will activate a diesel
engine to parallel with the hydro. The diesel engine will be set at a base load to maintain
reasonable fuel efficiency and avoid wet stacking or other adverse operating conditions.
With this project, the utilitys diesel generators will be turned off for a significant amount of the
time. This will extend the life of the diesels, reduce the frequency of diesel maintenance and
overhauls, reduce usage of consumables, and conserve fuel. The existing waste heat system
that serves the school from the diesel powerhouse will be fitted with an interruptible electric
heating system to keep the standby diesel generator set(s) warm and to continue providing
heat to the school.
Interruptible electric heating services can be implemented in a number of ways. This study
assumes that buildings are fitted with a second electric meter that includes a special relay
controlled by the hydro plant switchgear. The switchgear incrementally closes these
interruptible meter relays when the hydro has excess generating capacity until interruptible
services are using all of the available excess energy. This is a dynamic process, as total hydro
generation and prime utility load are constantly changing, and any given interruptible meter
may or may not have loads turned on when it is activated by the hydro plant switchgear. A
load bank would also be installed at the hydro powerhouse to allow the hydro controller to
regulate system voltage and frequency without using the interruptible meters when necessary.
Communications between the hydro plant switchgear and interruptible meters can use several
different forms, including internet, radio link, dedicated wire, power line carrier, or grid
frequency modulation.
3.3.3 Access
Construction access to the hydro powerhouse will generally follow the existing all terrain
vehicle (ATV) trail that heads up Knutson Creek valley from the airport quarry (Figure A 2). The
proposed hydro powerhouse site is located approximately 5,800 feet from the existing airport
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access road along the proposed hydro access road. The conceptual designs show the access
road located slightly to the east of the existing ATV trail. This alignment was selected to keep
the road as far away from Knutson Creek as possible to reduce the risk that future meanders of
Knutson Creek will wash out the access road. There are no significant known constraints
regarding the final alignment of this road.
Access to the remainder of the hydro project will take one of two routes. Heavy equipment for
construction and periodic maintenance will use a proposed 7,600 foot long access road from
the powerhouse to the intake, fording Knutson Creek above the powerhouse site at RM 1.30
and heading up the west side of Knutson Creek. Constraints on use of the fording location will
be part of the Fish Habitat Permit issued by ADF&G for the project.
A separate trail will follow the penstock route up the east side of Knutson Creek. This trail will
depart from the main access road approximately 600 feet above the powerhouse and continue
for 2,200 feet along the east side of Knutson Creek to a bridge crossing at RM 1.79. It will then
rejoin the main access road approximately 3,700 feet below the diversion site.
3.3.4 Diversion and Intake Structures
Diversion Structure
The project diversion structure site is at an exposed bedrock sill located at RM 2.59 (see
Photographs B 12 and B 13). The diversion structure will consist of a reinforced concrete wall
120 feet long and 0.5 to 7 feet tall. This wall will serve to impound water enough to divert the
project flow through a horizontal slot on the west 20 feet of this wall into the intake structure.
Excess water will flow over the easterly 100 feet of the wall, which will serve as the main
spillway. A short (0.25 foot tall) step halfway along the 100 foot long spillway will confine
lower flows to the west end of the spillway, discharging into the normal channel of Knutson
Creek. Higher flows will spill over the full 100 feet of spillway. A rock dike will extend from the
east end of the concrete spillway approximately 200 feet to the east side of the valley floor.
This dike will be designed to be overtopped by flood flows up to the estimated 500 year flood
event of 2,500 cfs. A similar dike will extend from the west end of the concrete spillway
structure approximately 240 feet to the west side of the valley floor. The west dike will be
taller than the east dike and will not be overtopped by the estimated 500 year flood event to
prevent flood damage to the intake, access road, work pad, penstock, and associated project
infrastructure located immediately downstream of the west dike.
Intake Structure
The intake structure will be a reinforced concrete structure located immediately downstream of
and adjacent to the west end of the concrete diversion structure. The intake structure will
receive raw water and debris from the diversion impoundment and into the intake forebay, and
then direct this flow over a coanda effect type screen. This screen will filter rocks, gravel, and
plant matter out of the water, with clean water collecting in the intake gallery beneath this
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screen. Filtered debris will be flushed off the screen and back to the main channel of Knutson
Creek by excess water flowing over the screen. Filtered water will flow by gravity from the
gallery into the penstock and to the powerhouse. The normal headwater elevation in the
intake gallery will be approximately 398.5 feet.
The diversion structure and intake structure will be fitted with gates to flush out accumulated
sediments and debris on an as needed basis. These gates may be remotely operated from the
hydro or diesel powerhouse by the plant operator.
3.3.5 Penstock
The penstock will be a 26 inch diameter HDPE pipe buried along the project access roads and
trails. The penstock will be buried in the main access road for the first 3,700 feet below the
intake. It will then depart the access road and cross to the east side of Knutson Creek via a 340
foot long bridge at RM 1.79. This bridge will also support ATV, snow machine, or pedestrian
traffic to the intake. The penstock then continues down the east side of Knutson Creek for
2,200 feet, rejoining the main access road 600 feet above the powerhouse. A trail will be built
along the portion of the penstock route deviating from the main access road to provide access
for penstock construction and ATV access to the intake site for routine operation and
maintenance purposes. Intake maintenance requiring heavy equipment will need to ford
Knutson Creek and use the construction access route along the west side of Knutson Creek.
The overall penstock length will be 7,080 feet. At the full design flow of 18.25 cfs, head losses
along the penstock will be approximately 17.3 feet. Most of the penstock will be low pressure
standard dimension ratio (SDR) 32.5 pipe. The approximately 1,000 feet of penstock
immediately above the powerhouse will be higher pressure SDR 26 and SDR 21 pipe. Power
and communications will be buried along the same route as the penstock to operate and
control equipment on the intake and diversion structures.
3.3.6 Powerhouse
The powerhouse will be a 20 by 24 foot building with 10 foot ceilings. The building will include
an overhead gantry beam to move the turbine and generator. The powerhouse will house the
turbine, generator, switchgear, and associated control systems for the project. The turbine will
be a single crossflow type turbine, and the generator will be a single phase synchronous
machine.12 Finished floor elevation in the powerhouse will be 178 feet. The tailrace finished
floor beneath the powerhouse will be 169.5 feet. The normal tailwater elevation will be
approximately 174.7 feet, resulting in a gross project head of approximately 223.8 feet and a
net operating head at full design flow of approximately 206.5 feet.
12 See Section H.1.1 in Appendix H for discussion of alternate turbine configurations that may be appropriate for
this project.
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4.0 ECONOMIC ANALYSIS
To evaluate the economic benefits of the hydro project, a comparative analysis was performed
between a hydro project and future diesel generation costs without a hydro project. Based on
this analysis, the hydro project is a lower cost power supply option for Pedro Bay Village than
continued purchase and consumption of diesel fuel, provided that the hydro projects excess
energy is used for space heating on an interruptible basis. Fitting buildings for interruptible
electric heating services is recommended to be an integral part of the hydro project in order to
realize the full project benefits.
This study conducted comparative analyses for a range of project capacities (100 to 1,000 kW).
Economic data for these alternate project capacities is presented in Section H.2 of Appendix H.
4.1 COST ESTIMATE FOR RECOMMENDED PROJECT
The cost estimate for the recommended project is presented in Table 4 1. This cost estimate
assumes the community contracts with a qualified construction firm to build the project.
Table 4 1 Estimate of Total Installed Cost for Recommended Project (200 kW)
Cost Item
Cost Estimate
(2012 $)
PRE CONSTRUCTION COSTS (STUDY, DESIGN, PERMITTING) $293,000
DIRECT CONSTRUCTION COSTS
Access Roads and Trails $370,000
Power and Communications Lines $375,000
Diversion and Intake Structures $259,000
Penstock $743,000
Building Conversions for Interruptible Electric Heating Service $310,000
Powerhouse $700,000
Shipping/Mobilization/Equipment $555,000
TOTAL DIRECT CONSTRUCTION COSTS $3,312,000
Construction Contingency (20%) $662,000
Construction Management/Administration $120,000
Construction Inspection/Engineering $115,000
ESTIMATED TOTAL INSTALLED COST $4,502,000
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4.2 ECONOMIC EVALUATION OF RECOMMENDED PROJECT
The economic analysis of the hydro project was performed on a relative basis, using continued
operation of the diesel power plant as the reference case. Estimates of major differential costs
were developed for the analysis, which included:
1) Annual costs for hydro project operation, maintenance, repair, and replacements,
2) Annual savings from reduced fuel usage, operations, and maintenance costs at the
diesel power plant,
3) Capital costs of the hydro project, and
4) Salvage value of the hydro project at the end of its life.
All of these expense items were considered over the 50 year life of the project, and then
converted to present value amounts. The present value of the projects benefits and costs
(relative to continued use of the diesel power plant) were then compared to determine the
projects estimated benefit cost ratio. The electric utilitys general and administrative costs are
assumed to be constant for both cases, and so were not considered. Similarly, the diesel power
plant will be needed for both cases, so capital outlays for the diesel plant beyond O&M savings
are also not considered. Major assumptions used in the economic analysis of the project are
summarized in Table 4 2. These assumptions are discussed in greater detail in Appendix G.
Table 4 2 Base Case Assumptions Used for Economic Analysis
Utility Assumptions Value
Annual Electric Demand 182,200 kilowatt hours (1)
Diesel Power Plant Fuel Efficiency 10.5 kWh generated per gallon
(1)
Annual Utility Fuel Usage for Electricity Generation 17,352 gallons
(1)
Per Gallon Fuel Cost to Utility $5.83 per gallon
(2)
Total Annual Utility Fuel Costs $101,162
Utility Load Projections Flat at current load level
(4)
Economic Model Assumptions
Hydro Project Salvage Value (Year 50) $0
(4)
Construction and Commissioning Year 2016
(4)
Project Financing Debt financing, Grant financing
(5)
Debt term 30 years
(4)
Debt interest rate 5%
(6)
Real discount rate 3%
(4)
(1) Approximate annual average for the utility from 2011 to 2013, as determined from PCE program and utility records.
(2) 2012 fuel cost as estimated by the Institute of Social and Economic Research (ISER, 2012).
(4) Assumed value.
(5) The economic analysis for grant financed project used the economic model developed for the AEAs Renewable Energy
Grant Program by ISER (Round 6 version, released July 2012) (AEA, 2012a).
(6) Assumed interest rate is based on the interest rate for the Sustainable Energy Transmission and Supply Development
Loan Program administered by the Alaska Industrial Development and Export Authority as of November 2013. The Power
Project Fund also has an interest rate ranging from 0 to 6%.
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Two financing alternatives were evaluated for the projects capital costs: (1) debt financing and
(2) grant financing.
13 Table 4 3 summarizes the annual costs and savings of the recommended
project for both debt and grant based financing alternatives.
Table 4 3 Summary of Economic Data for Recommended Project
Parameter
Values Used
for Economic
Analysis
ECONOMIC EVALUATION OF DEBT FINANCED PROJECT (Relative to continued diesel generation)
PROJECT BENEFITS
Annual Reduction in Utility Fuel Purchases due to Hydro Project 16,600 gallons
Annual Reduction in Heating Fuel Purchases due to Interruptible Electric Heating Services 24,200 gallons
Annual Savings from Avoided Diesel Plant Operating and Maintenance Costs $15,000
Salvage Value (at year 50) $0
PRESENT VALUE OF PROJECT BENEFITS $7,334,000
PROJECT COSTS
Estimated Total Installed Cost of Project (study, permitting, design, and construction) $4,502,000
Financed Project Cost $4,212,000
Annual Cost of Debt Servicing (for 30 years) $317,600
Estimated Annual Hydro Plant Operations, Maintenance, Repair and Replacement Costs
(for 50 years)
$29,000
PRESENT VALUE OF PROJECT COSTS $6,234,000
BENEFIT COST RATIO (DEBT FINANCED PROJECT) 1.18
ECONOMIC EVALUATION OF GRANT FINANCED PROJECT (Relative to continued diesel generation)
PRESENT VALUE OF PROJECT BENEFITS $8,280,000
PRESENT VALUE OF PROJECT COSTS $4,132,000
BENEFIT COST RATIO (GRANT FINANCED PROJECT) 2.00
NOTE: See Appendix G (Section G.2) for assumptions used in the economic analysis and the project cost estimate. All dollar
amounts are in 2012 dollars.
Table 4 3 assumes that most of the community buildings and homes in Pedro Bay Village are
fitted for interruptible electric heating services in order to use as much of the hydro project
output as possible. The estimated cost of these conversions is included in the projects total
installed cost estimate. If the hydro project is instead used to supply only the existing electric
utility demand, the hydro projects benefit cost ratio is much lower, at approximately 0.6 to 1.0
(depending on hydro project configuration and financing). This underscores the importance of
13 The grant financed scenario is developed using the economic model developed by ISER and used by AEA to
evaluate applications to the Renewable Energy Grant Program (ISER, 2012b).
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using excess energy from the project with interruptible electric heating services, or a similar
beneficial application.
4.3 PROJECTED ELECTRICITY RATES WITH RECOMMENDED PROJECT
Table 4.4 presents estimated PBVC electric rates with the recommended project. Three
potential rate scenarios are presented two for a debt financed project, and a third for a grant
financed project. Assumptions used to develop these estimated rates are discussed in Section
G.3 of Appendix G.
Table 4 4 Estimated PBVC Electric Rates with Recommended Project
Estimated Electric Rates
Project Scenario
Interruptible
Heating Service
(No PCE Subsidy)
Prime Energy Service
(Standard Service)
(Before PCE Subsidy)
Prime Energy Service with
PCE Subsidy (Residential and
Community Services Only)
(1)
Debt Financed Hydro Project
(Discounted Rate for
Interruptible Heating Service)
(2)
$0.198 per kWh $1.255 per kWh $0.255 per kWh
Grant Financed Hydro Project $0.065 per kWh $0.065 per kWh
$0.065 per kWh
(no PCE subsidy)
Current Electric Rate NA $0.910 per kWh $0.173 per kWh
Current Equivalent Cost of
Heating Fuel for Buildings
$0.220 per kWh
(3)NA NA
NOTES:
(1) Based on the fiscal year 2012 PCE base rate of $0.1342 per kWh and full funding for the PCE program. The PCE program
reimburses the utility for up to 500 kWh per month per residential account and for certain community accounts. The
subsidy level is 95% of the difference between the utility rate (up to $1.00 per kWh) and the base rate.
(2) If the hydro project is debt financed, a discounted interruptible service rate is necessary to provide a financial incentive
for ratepayers to convert to interruptible electric heating service. A rate equal to a 10% discount from fuel oil prices is
assumed. This results in a significant rate increase from existing rates for standard electric service.
(3) Based on an assumed heating equipment efficiency of 84%, $7.60 per gallon cost, and 140,000 btu/gallon heat content.
kWh kilowatt hour
NA not applicable
PCE Power Cost Equalization (program)
The estimated rates for a debt financed project presented in Table 4 4 reveal a challenge with
debt financing for this project. Interruptible energy rates must be competitive with heating oil
which limits the revenue from interruptible energy sales. The resulting rates for prime energy
service must then cover the utilitys remaining costs, resulting in rates that are significantly
higher than existing rates.
This conundrum is a function of the particular debt parameters and energy usage patterns that
result from the recommended project configuration and economic evaluation assumptions, and
can be resolved through a combination of grants and/or low cost financing. The electric rates
with a fully grant financed hydro project (6.5 cents per kWh for both interruptible and prime
energy services) represent the lower end of probable electric rates with the recommended
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hydro project. Rural utilities commonly use a combination of grants and low cost loans to
develop acceptable project economics.
With a fully grant financed hydro project, PBVC ratepayers would no longer qualify for PCE
subsidies as the electric rate would be too low. With a debt financed project, PBVC ratepayers
would likely continue to receive PCE subsidies for eligible kWh usage.
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4.4 SENSITIVITY ANALYSIS
A sensitivity analysis was performed to determine how sensitive the economic analysis
conclusions are to variations in assumptions and input parameters. The assumptions and
inputs reviewed and the results are summarized in Table 4 5 for a debt financed project. For
each variable, the input range considered, resulting range of BCR, and value that results in a
BCR of 1.00 are presented. Generally, the BCR of a grant financed project is higher for a given
set of conditions, so evaluating debt financed conditions provides a more rigorous test of the
projects economics.
Table 4 5 Sensitivity Analysis Results (Debt Financed Project)
Parameter Base Case Value
(BCR of 1.18)
Range
Considered
Range of
Resulting BCR
Value for BCR of
1.00 (1)
Installed Cost $4,502,000 +/25% 0.95 1.54 $5,357,000
(+19%)
System load and
Growth trend
182,200 kWh
(No growth)
91,100 to 728,800 kWh
(50% to +400%)
(2)0.98 2.23 45%
In Stream Flow
Reservation (ISFR)
6.6 cfs 0 to 20 0.86 1.29 14 cfs
Incremental Annual
Operations Costs
$29,000/year +/50% 1.11 1.25 +260%
($79,900/year)
Financing Rate 5% 0 to 8% 0.89 2.07 6.7%
Cost of Fuel
(3)$5.83 per gallon 50% to 200% 0.62 2.30 16%
($4.89 per gallon)
Percent Utilization
of Excess Energy
82% 0% to 100% 0.51 1.34 63%
Environmental
Attributes Sales
Price
$0.00 per kWh $0.00 to $0.03 1.18 1.30 NA
NOTES:
(1) The feasibility level project cost estimate includes a 20% contingency on the construction cost.
(2) Load growth cases assume a constant load over the projects economic life at the stated percentage of existing annual
load.
(3) Range of fuel costs is applied to both power plant fuel and heating fuel.
BCR benefit cost ratio
NA Not applicable because variations in the parameter cannot result in a BCR of 1 or less.
Based on this analysis, the project economics are most sensitive to the following four
parameters:
(1) Percent utilization of excess energy,
(2) Cost of fuel,
(3) In stream flow reservations (ISFRs), and
(4) Installed cost.
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Percent Utilization of Excess Energy
Retrofitting public buildings and homes in Pedro Bay to receive interruptible excess energy
from the hydro project on an interruptible basis is critical to realizing the full economic benefits
of the project. Analysis indicates that fitting seven community buildings and 33 homes for
interruptible electric heating is sufficient to use 78% of the excess energy available from the
recommended hydro project under existing utility load characteristics. Without fully
developing this market for the projects energy, the projects benefits are significantly reduced.
Cost of Fuel
The projects benefits are sensitive to the price of fuel. Under the 100% debt financed
alternative for the project, the BCR is 1.00 at a 2012 fuel price of $4.89 per gallon. PBVCs fuel
costs were less than this amount as recently as March 2011. While the long term fuel cost is
considered unlikely to be below $4.89 per gallon in Pedro Bay, it is possible that prices will fall
below this level for a season or more in the early years that the project is operational.
In Stream Flow Reservations (ISFRs)
High ISFRs will reduce or eliminate the ability of the project to produce electricity during the
late winter months, reducing the projects benefits without reducing the projects costs. If
possible, off site compensatory habitat should be constructed in lieu of ISFRs, or in exchange
for decreased ISFRs.
Installed Cost
Construction cost overruns on small hydroelectric projects such as that recommended for
Pedro Bay can significantly reduce the projects benefits. Proper project design and
construction management are both key to a successful on budget project. An adaptive design
that can quickly address changing field conditions using on site materials, equipment, and labor
will help to control construction costs. In addition, selecting a contractor with both local
experience and small hydro experience will help avoid problems during construction. Using
force account construction with a capable superintendent instead of a contractor for all or
parts of the project can also be a good strategy to help the PBVC control construction costs.
Additionally, the challenging logistics and high transportation costs to Pedro Bay mean that
significant attention should be paid to early planning for the project. Last minute shipping of
minor materials due to incomplete material take offs, extended lease terms of imported
construction equipment due to poor planning or unforeseen site conditions, and similar factors
can rapidly increase project costs.
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5.0 CONCLUSIONS AND RECOMMENDATIONS
The run of river hydroelectric project on Knutson Creek recommended in this report will supply
95.6% of Pedro Bays existing electrical demand in an average water year. Additionally, it will
supply approximately 86% of the space heating needs of Pedro Bays community buildings, and
approximately 56% of the space heating needs of homes in the community.
At an estimated installed cost of $4,502,000, the recommended project as an estimated BCR of
1.18 to 2.00 compared to continued reliance on diesel fuel for electricity generation. This BCR
range includes the significant space heating benefits the project is capable of supplying to the
community. Indeed, using the projects output for interruptible electric heating services is
critical to realizing the full benefits of the project.
These findings are based on an assumed ISFR of 6.6 cfs year round, equal to 50% of the average
annual low flow in Knutson Creek at the diversion site. Project benefits improve with a lower
ISFR and decrease with higher ISFRs. Accordingly, negotiating reasonable conditions for the fish
habitat permit for the project will directly impact the projects benefits for the community.
Permit negotiations with the ADF&G should emphasize compensatory off site anadromous
habitat as mitigation for reducing flows in the bypass reach rather than establishing excessive
ISFRs for the marginal anadromous habitat in the bypass reach of Knutson Creek (See Appendix
E). ISFRs in the bypass reach of Knutson Creek represent a direct trade off between providing
for the sustainability of Pedro Bay Village versus preserving marginal anadromous fish habitat in
the bypass reach of Knutson Creek.
Based on the findings of this study, continued development of the project is warranted as the
project can provide a significant long term benefit to Pedro Bay Village. The next major steps
to develop the project are:
(1) Initiate the permitting process for the project.
(a) Prepare and file a Declaration of Intention with the Federal Energy Regulatory
Commission (FERC) to determine if the project falls under FERC jurisdiction.
This will influence the course of permitting for the project, and will also effect
the projects life cycle costs.
(b) Continue consultations with ADFG regarding conditions associated with the
fish habitat permit. Opportunities for off site mitigation, and on site
mitigation within the project tailrace, should be discussed with ADFG
personnel to maximize project benefits.
(2) Continue collecting hydrology data at the diversion, gauging station, and tailrace sites
along Knutson Creek, as well as at tributaries R1 and L1, to support efforts to secure a
fish habitat permit with reasonable conditions for the project.
(3) Complete design of the project, which will include the following:
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Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report 36
(a) Analysis of optimal project capacity once permit conditions are known and
additional site information is available.
(b) More detailed analysis of existing space heating demand in Pedro Bay (e.g.,
fuel usage, building details) to refine the quantity of excess hydro energy that
can be dispatched to space heating loads and the extent of upgrades needed
to implement electric heating services.
(c) Development of financing plans and rate schedules for standard electric
service and interruptible electric heating service to encourage conversion to
interruptible heating service and maximize project benefits to the community.
Figure 5 1 provides the completed to date and anticipated future project schedule and
milestones.
Figure 5 1 Project Development Schedule
2009 2010 2011 2012 2013 2014 2015 2016
ACTIVITY 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
Reconnaissance Study (Completed)
Feasibility Study (Completed)
Permitting
FERC Non Jurisdiction
Other Permitting and Authorizations
Project Design
Construction Plan
Financing Plan
Construction
Project Commissioning
Construction Phase Close out
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November 2013 Final Report 37
6.0 REFERENCES
Alaska Department of Commerce, Community, and Economic Development (ADCCED). 2012.
Pedro Bay. Web site:http://www.commerce.state.ak.us /dca/commdb/CIS.cfm?
Comm_Boro_name=Pedro%20Bay
Alaska Department of Commerce, Community, and Economic Development (ADCCED). Division
of Community and Regional Affairs. 1995. Pedro Bay Distribution Upgrade Drawings.
March 20.
Alaska Department of Labor and Workforce Development. American Community Survey. Web
site:http://labor.alaska.gov/research/census/
Alaska Energy and Engineering, Inc. (AEE). 2003. Pedro Bay Bulk Fuel Consolidation and
Upgrade Concept Design Report.
Alaska Energy and Engineering, Inc. (AEE). September 7, 2005. Pedro Bay Power System
Upgrade Record Drawings.
Alaska Energy and Engineering, Inc. (AEE). 2013. Pedro Bay Heat Recovery Expansion Red Line
Drawings. September 21, 2013.
Alaska Energy Authority (AEA). 2012a. Renewable Energy Fund Round 6. Web site:
http://www.akenergyauthority.org/RE_Fund 6.html. July.
Alaska Energy Authority (AEA). 2012b. Power Cost Equalization. Web site:
http://www.akenergyauthority.org/programspce.html
Alaska Energy Authority (AEA). 2012c. Pedro Bay Easygen Upgrade Design Drawings,
Controlled Power, Inc. (#7443) and Alaska Energy Authority (PO RQ 4071). January 19,
2012.
Alaska Energy Authority (AEA). 2012d. Undated red lines of August 12, 2004 Switchgear Design
Drawings, Controlled Power, Inc. (#5823) and Alaska Energy Authority (PO REG 04 230)
Provided by AEA on November 8, 2013.
Alaska Energy Authority (AEA).2010. Alaska Energy Plan Community Database. Web site:
http://www.akenergyauthority.org/alaska energy plan.html
Institute of Social and Economic Research (ISER), University of Alaska Anchorage. 2012a.
Internal Publications Database Search. Web site: http://www.iser.
uaa.alaska.edu/publications.php?id=1518
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report 38
Institute of Social and Economic Research (ISER), University of Alaska Anchorage. 2012b.
Alaska Fuel Price Projections 2012 2035. ISER Working Paper 2012.1 and Microsoft
Excel Spreadsheet Price Model. July.
U.S. Army Corps of Engineers (USACE). 2007. Alaska Baseline Erosion Assessment: Erosion
Information Paper Pedro Bay, Alaska. October 19.
U.S. Census Bureau. 2010 Census. Web site:http://2010.census.gov/2010census/
U.S. Geological Survey (USGS). 2003. Estimating the Magnitude and Frequency of Peak
Streamflows for Ungaged Sites on Streams in Alaska and Conterminous Basins in
Canada: Water Resources Investigations Report 2003 4188. By Curran, Janet H.; Meyer,
David F.; and Tasker, Gary D.
USGS. 1973. Surficial Deposits of the Iliamna Quadrangle, Alaska: Geological Survey Bulletin
1368 A. By Detterman, Robert L. and Reed, Bruce L.
USGS. 1980. Stratigraphy, Structure, and Economic Geology of the Iliamna Quadrangle, Alaska:
A Comprehensive study of Mesozoic to Holocene Sedimentary, volcanic, and plutonic
rocks of the Iliamna Quadrangle. Geological Survey Bulletin 1368 B. By Detterman,
Robert L. and Reed, Bruce L.
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APPENDIX A PROJECT MAPS
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Figure A 1 Project Overview and Location Map
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Figure A 2 Map of Recommended Knutson Creek Project
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Figure A 3 Knutson Creek and Iliamna River Drainage Basins and Subbasins
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APPENDIX B SITE PHOTOGRAPHS
Photograph Title Page Nos.
Photograph B 1 Exterior View of Existing Pedro Bay Diesel Power House........................B 2
Photograph B 2 Interior View of Existing Pedro Bay Diesel Power House........................B 2
Photograph B 3 Upper Gauging Station Looking Upstream..............................................B 3
Photograph B 4 Natural Outlet Control Structure at Upper Gauging Station...................B 3
Photograph B 5 View of Knutson Creek Reach at Lower Gauging Station........................B 4
Photograph B 6 View of Knutson Creek Lower Gauging Station.......................................B 4
Photograph B 7 View of Knutson Creek at River Mile 2.2, Looking Upstream..................B 5
Photograph B 8 View of Knutson Creek at River Mile 1.5, Looking Downstream.............B 5
Photograph B 9 View of Knutson Creek Downstream of Upper Gauging Station.............B 6
Photograph B 10 Oblique Aerial View of Lower Knutson Creek..........................................B 8
Photograph B 11 Oblique Aerial View of Upper Knutson Creek..........................................B 8
Photograph B 12 Proposed Knutson Creek Diversion Site Looking Downstream...............B 9
Photograph B 13 Proposed Knutson Creek Diversion Site Looking Upstream..................B 10
Photograph B 14 Oblique View of Proposed Penstock Bridge Site Over Knutson
Creek ................................................................................................................B 10
Photograph B 15 Elevation View of Proposed Penstock Bridge Site over Knutson
Creek ................................................................................................................B 11
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Photograph B 1 Exterior View of Existing Pedro Bay Diesel Power House
Polarconsult, July 21, 2009.
Photograph B 2 Interior View of Existing Pedro Bay Diesel Power House
Polarconsult, July 21, 2009.
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Photograph B 3 Upper Gauging Station Looking Upstream
Polarconsult, April 19, 2012.
Photograph B 4 Natural Outlet Control Structure at Upper Gauging Station
Polarconsult engineer Gary Paulus measuring stream flow in Knutson Creek at the upper gauging station site at
river mile 2.10. The mouth of tributary L1is visible at far right. Measured flow is 78.1 cfs.
Polarconsult, October 15, 2010.
View of upper gauging station at river
mile 2.10, looking upstream.
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Photograph B 5 View of Knutson Creek Reach at Lower Gauging Station
Stream gauging station installed October 12, 2010, at river mile 2.04. The index bolt is an arbitrary elevation of
3.00 feet (to top of bolt).
Polarconsult, October 11, 2010.
Photograph B 6 View of Knutson Creek Lower Gauging Station
Lower gauging station installed October 12, 2010, at river mile 2.04. This view is taken from a cliff on the west side
of Knutson Creek. The measured stream flow is approximately 83 cfs.
Polarconsult, October 14, 2010.
HDPE pipe housing
sensor and data logger
Download/charging
cable enclosure
Index bolt
Lower Gauging
Station
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Photograph B 7 View of Knutson Creek at River Mile 2.2, Looking Upstream
View upstream from river mile 2.2 on Knutson Creek. This view shows representative creek grade, section, and bed
materials for the reach from river miles 2.1 through 2.5.
Polarconsult, October 13, 2010.
Photograph B 8 View of Knutson Creek at River Mile 1.5, Looking Downstream
View downstream from river mile 1.5 on Knutson Creek. The creek section widens and grade decreases as it enters
the alluvial cone.
Polarconsult, October 11, 2010.
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Photograph B 9 View of Knutson Creek Downstream of Upper Gauging Station
Polarconsult engineer Gary Paulus measuring stream flow in Knutson Creek at the upper gauging station
site at river mile 2.10. The lower gauging station is located just out of view on the east bank
downstream at photograph left.
Polarconsult, October 11, 2010.
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Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportB8TributaryL1Diversion SiteTributaryR2TributaryR1PowerhouseEquipment Access RoutePenstock BridgeLower Gauging StationUpper Gauging StationPhotograph B10 Oblique Aerial View of Lower Knutson CreekPhotograph B11 Oblique Aerial View of Upper Knutson CreekTributaryR1PowerhouseEquipment Access RoutePenstock RouteTailraceOblique aerial view looking westsouthwest over lower KnutsonCreek from its mouth on Lake Iliamna up to approximately rivermile 1.75. The approximate locations of key project features areshown.Polarconsult, April 26, 2012.Oblique aerial view looking westsouthwest over upperKnutson Creek from approximately river mile 1.0 up to approximately rivermile 3.0. The approximate locations of key project features are shown.Polarconsult, April 26, 2012.
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportB9Photograph B12 Proposed Knutson Creek Diversion Site Looking DownstreamView of proposed Knutson Creek diversion site at RM 2.59 looking downstream (southsouthwest). Polarconsult engineer Gary Paulus is standing on a bedrock outcrop that extendsback toward the east bank and extendsunder the creek channel. The bedrock disappears beneath boulders and cobbles on the west bank of Knutson Creek. The red line traces the approximate bedrock contour.Polarconsult, October 14, 2010.?
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportB10Photograph B13 Proposed Knutson Creek Diversion Site Looking UpstreamPhotograph B14 Oblique View of Proposed Penstock Bridge Site Over Knutson CreekView of proposed penstock bridge site over Knutson Creek from vicinity of east abutment. The approximate penstock alignment is shown in dark red.Polarconsult, May 5, 2011.View of proposed Knutson Creek diversion site at RM 2.59 looking upstream (northnortheast). Polarconsult engineer Gary Paulus is standing ona bedrock outcrop that extends back toward the east bank, and extends under the creek channel. The bedrock disappears beneath boulders andcobbles on the west bank of Knutson Creek.Polarconsult, October 14, 2010.
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportB11Photograph B15 Elevation View of Proposed Penstock Bridge Site over Knutson CreekView of proposed penstock bridge site over Knutson Creek from upstream. The approximate bridge location is shown in dark red.Polarconsult, May 5, 2011.
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APPENDIX C HYDROLOGY DATA
Section Title Page Nos.
C.1 Available Hydrology Data......................................................................... C 2
C.2 Stream Gauge Station Information.......................................................... C 4
C.3 Flow Measurements and Station Calibration .......................................... C 6
C.4 Knutson Creek Hydrology Data ............................................................... C 8
C.5 Knutson Creek Hydrology Model........................................................... C 12
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C.1 AVAILABLE HYDROLOGY DATA
Approximately 1.9 years of hydrology data have been collected at Knutson Creek. Two gauging
stations have been installed at Knutson Creek; these are described in Section C.2. This
appendix summarizes the hydrology data and analysis used for this study. Appendix J provides
the daily stage and calculated flow data for both gauging stations in tabular form.
The collected hydrology information is used to determine the appropriate installed capacity of
the hydroelectric project, evaluate the expected performance of the project, and help
determine the magnitude of flood flows at Knutson Creek. Moreover, this hydrology
information can help assess the effect the project may have on the natural environment.
Existing hydrology data are summarized in Table C 1. Flow measurements at the Knutson Creek
gauging stations are summarized in Table C 2. Hydrographs, stage discharge curves,flow
duration curves, and station notes for both gauges are included in this appendix.
Table C 1 Summary of Hydrology Data for Knutson Creek
Location USGS
Gauge ID
Basin
Size
(square
miles)
Site
Elevation
(ft)(1)
Latitude(1)Longitude(1)Begin
Date End Date
Number
of Daily
Records(2)
Iliamna River 15300300 128 80 59d4531153d50415/24/96 Current 5,936
Knutson Creek
Upper Gauge
NA 30.0 310 59d4911154d065411/10/11 Current
(3)2
Knutson Creek
Lower Gauge
NA 33.1 300 59d4909154d065610/12/10 Current
(3)555
NOTES:
(1) Coordinates for U.S. Geological Survey gauges are in North American Datum of 1927 (NAD 27). All other coordinates are
in NAD 83. Knutson Creek gauging station elevations are in the project vertical datum.
(2) The record count for current gauging stations includes data through the most recent download of the Knutson Creek
gauges on August 25, 2012.
(3) Current status of both gauging stations is unknown. Both stations were in good working order at Polarconsults last field
visit on August 25, 2012.
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Table C 2 Flow Measurements at Knutson Creek and Tributaries
Date and Time Party
Measured
Flow (cfs)
Measuremen
t Quality
Stage at Upper
Gauging Station
(ft)(4)
Stage at Lower
Gauging Station
(ft)(5)
Method/Equipm
ent
Knutson Creek Tributary R1(at 450elevation)
7/22/2009 13:45 Groves/Foss 43 Poor Salt (2), (6)
10/14/2010 17:30 Groves/Paulus 3.7 Good Salt (2)
Knutson Creek Tributary L1(at mouth on Knutson Creek)
10/11/2010 16:00 Paulus/Groves 3.7 Very Poor CV (1), (6)
Knutson Creek at Upper Gauging Station
10/11/2010 15:30 Paulus/Groves 100.9 Good 2.16 1.53 CV
(1)
10/15/2010 12:30 Paulus/Groves 78.1 Good 2.03 1.51 CV
(1)
5/4/2011 11:50 Groves/Foss 51.3 Fair 1.83 1.40 CV
(1)
4/19/2012 16:45 Groves/Dahl 32.8 Fair 1.63 1.30 Salt
(2)
Knutson Creek at Lower Gauging Station
2/4/2011 11:45 Paulus/Foss 38.2 Fair 1.21 Salt
(2)
4/11/2011 14:30 Groves/Foss 10.2 Good 1.03 1.04 Salt
(2)
7/20/2012 12:15 Groves 400 2.91 1.90 Visual estimate
(3)
8/24/2012 15:30 Groves 200 2.50 1.65 Visual estimate
(3)
NOTES:
(1) Current velocity (CV) stream flow method with Marsh McBirney Flo Mate2000 Portable Velocity Flow at 40 second
averaging interval. Reported value is the average of two concurrent measurements unless otherwise noted.
(2) Sudden dose salt integration stream flow method with Hanna HI 9828 conductivity meter. Reported value is the average
of two concurrent measurements unless otherwise noted.
(3) Flow conditions unsafe for current velocity measurement methods. Velocity, depth, and width were partially measured
and/or estimated in order to estimate total flow.
(4) Creek stage is based on manual tapedown measurements from the top of a ¼inch bolt set in rock at the site. The bolt
elevation is +4.70 feet. The approximate point of zero flow for this station is 0.00 feet in this datum.
(5) Creek stage is based on manual tapedown measurements from the top of a ¼inch bolt set in rock at the site. The bolt
elevation is +3.00 feet. The approximate point of zero flow for this station is 0.00 feet in this datum.
(6) Only one measurement taken.
Indicates data are not available.
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C.2 STREAM GAUGE STATION INFORMATION
Both the lower and upper gauging station sites were identified in October 2010 as good gauging
station locations. The lower station has mediocre low flow stage resolution but is well
protected from high flow hazards and has a deep pool to protect the pressure and temperature
transducer (PTT) from freezing. The upper station has superior low flow stage resolution but is
subject to high flow hazards and freezing conditions. The history of both stations is described
in detail in this section.
C.2.1 Lower Knutson Creek Gauging Station
On October 12, 2010, Polarconsult installed a gauging station (the lower gauging station)at
RM 2.04 on Knutson Creek, at about the midpoint of the proposed project bypass reach (see
Figure A 2). This station was selected based on the perceived stability of the creek bed in the
immediate station vicinity, the relative protection from flood debris and velocities, its
accessibility from Pedro Bay Village for downloading and maintenance, and the presence of a
deep pool to protect the PTT from freezing during the winter months.
The lower gauging station is in a small, deep pool on the inside (east) bank of Knutson Creek
where it negotiates a series of sharp turns through a rock canyon. The pool is on the periphery
of the creek bed at this location, with the main channel approximately 40 feet to the west and
approximately 4 feet below the pool elevation. The outlet of this pool is controlled by a series
of 2 to 4 foot diameter boulders well embedded in the creek bottom. Flow is directed to this
pool year round by a series of cobble and boulder bars located approximately 100 feet
upstream (see Photographs B 5 and B 6).
Instrumentation at this gauging station is a model DCX ECO18VG vented PTT and data logger
manufactured by Keller America, Inc. The PTT is programmed to measure water depth and
temperature at 30 minute intervals, providing approximately 9.5 months of memory capacity.
The PTT is mounted within a 3 inch diameter HDPE stilling tube fastened to two large boulders
on the stream bank with steel pipe clamps and rock bolts. The PTT is secured within the stilling
tube with a 1 inch diameter segment of polyvinyl chloride (PVC) tube. The PVC tube is pinned
to the stilling tube to prevent vertical movement of the PTT. At annual low flow conditions, the
PTT is immersed in approximately 1.3 feet of water. The vent and data cable is routed through
liquidtite flexible metal conduit (LFMC) up to a nearby cottonwood tree, providing easy access
for download and charging. The rechargeable battery is sufficient for 1+ years of operation on
a single charge.
The vertical datum for this station is the top of a ¼inch rock bolt drilled into one of the
boulders at the station. The rock bolt is located approximately 4 feet upstream of the stilling
tube and PTT installation. The top of the rock bolt is +3.00 feet in the station datum. The
approximate point of zero flow for the pool outlet control is 0.00 feet in this datum.
This hardware has remained in service at this station without problems from October 12, 2010,
through the most recent download on August 25, 2012.
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C.2.2 Upper Knutson Creek Gauging Station
The upper gauging station is located immediately upstream of the mouth of tributary L1 at RM
2.10. A ¼inch index bolt was installed on a bedrock outcrop at this station in October 2010 to
establish a vertical datum for the station. The top of the bolt is +4.70 feet in the station datum.
The approximate point of zero flow for the station is 0.00 feet.
This station is approximately 300 feet upstream of the lower gauging station. It was selected
based on the perceived stability of the creek bed in the immediate station vicinity and the good
outlet control, which consists of a string of well embedded boulders spanning the
approximately 40 foot wide channel. This station lacks an accessible pool and is subject to
inundation and high velocities during high flow events, which places any instrumentation
installations at risk. This station also features one of the better locations for performing
current velocity measurements on Knutson Creek between approximately RM 1.00 and
RM 2.75.
Upon review of 2010 11 winter stage data from the lower gauging station, instrumentation was
installed at the upper gauging station on November 10, 2011, to improve the low flow record
for Knutson Creek. Instrumentation at this gauging station is a model DCX 22VG vented PTT
and data logger manufactured by Keller America, Inc. The PTT is programmed to measure
water depth and temperature at 30 minute intervals. At annual low flow conditions, the PTT is
immersed in approximately 0.8 feet of water. The PTT was mounted directly in the stream,
clamped to a section of liquidtite flexible conduit (LFC). The LFC was fastened to 20 feet of an
exposed rock outcrop and back to the east stream bank. The vent tube/data cable was routed
through the LFC to a small enclosure mounted to a rock face on the stream bank (see
Photograph B 3). This installation survived the winter of 2011 12, but the July 20, 2012, site
visit revealed that the PTT enclosure had been ripped away from the LFC by high flows. The
enclosure was inaccessible under snowdrifts during the April 11, 2012, site visit, so the data
from this installation were lost.
A second DCX 22VG was installed on August 24, 2012, to replace the lost instrumentation. The
PTT/data logger installation was reinforced with a 2x4 anchored to bedrock, and the LFC was
reinforced with additional anchors to the bedrock. Additionally, a 1/8 inch steel cable was fixed
to the PTT and run through the LFC and anchored to bedrock to help prevent loss of the
PTT/data logger. The DCX 22VG is fitted with a non rechargeable battery with a 5 year life.
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y = 1.3072e1.9943x
R2 = 0.9984
0
50
100
150
200
250
300
350
400
450
500
0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50
Creek Stage (feet, station datum)
Upper Station Rating Curve
Expon. (Upper Station Rating Curve)
(estimate)
(estimate)
C.3 FLOW MEASUREMENTS AND STATION CALIBRATION
The stage discharge curve for each gauging station has been developed by measuring flow in
Knutson Creek multiple times between October 2010 and August 2012 (Table C 2).
Measurements at the upper or lower gauging stations are adjusted to the other station by
scaling the measured flow by the ratio of the basin areas above each station.
The existing flow measurements and calibrated sections of the stage discharge curves have
good confidence at low and medium flows (up to 100+ cfs), which are of primary interest for
hydropower assessment of Knutson Creek. Additional high flow measurements would be
useful to increase confidence in the upper end of the stage discharge curves. These data would
improve estimates of infrequent high flow events that have limited hydropower value but are
important for design of the diversion structure.
Stage discharge curves for each station are empirical best fit equations. The stage discharge
curves are presented on Figure C 1 and C 2 for the upper and lower Knutson Creek gauging
stations, respectively.
Figure C 1 Stage Discharge Curve for Knutson Creek Upper Gauging Station
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y = 0.1152e4.3857x
R2 = 0.9879
0
50
100
150
200
250
300
350
400
450
500
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
Creek Stage (feet)
Lower Station Rating Curve
Expon. (Lower Station Rating Curve)
(estimate)
(estimate)
Figure C 2 Stage Discharge Curve for Knutson Creek Lower Gauging Station
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C.4 KNUTSON CREEK HYDROLOGY DATA
Hydrology data for the lower Knutson Creek gauging station are presented in this section. No
hydrology data have been recorded at the upper station due to the loss of the first PTT (winter
2011 12 data) in early summer 2012. Data on the second PTT installed in August 2012 have not
been downloaded yet.
Figure C 3 presents measured and recorded stage and temperature data at the lower gauging
station for the full period of record. Figure C 4 presents calculated and measured flow data at
the lower gauging station for the full period of record. Calculated flow data on Figure C 4 is
based on the stage discharge curve and equation presented on Figure C 2. Apparent ice
affected stage data, as determined by field observations, flow measurements, and concurrent
weather records, have been adjusted to provide an estimate of actual flow.
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Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportC10Water Temperature (F)Creek Stage (ft, Lower Gauge Site Datum)Knutson Creek Flow atLower Gauge Station (cfs)Figure C3 20102012 Knutson Creek Stage and Temperature DataFigure C4 20102012 Knutson Creek Flow Data
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0
10
20
30
40
50
60
70
80
90
100
Jan 1 Feb 1 Mar 3 Apr 3 May 4 Jun 4 Jul 5 Aug 5 Sep 5 Oct 6 Nov 6 Dec 7
Flow at Proposed Intake Site, cfs
Median Daily Flow
Mean Daily Flow
(Knutson Creek extended record based on gauged Knutson Creek flow Oct. 2010 - April 2011 and correlated Iliamna River flow 1996 - 2011)
C.5 KNUTSON CREEK HYDROLOGY MODEL
Brailey Hydrological Consultants, Inc. (BHC) was contracted to analyze the 1.9 years of stream
flow data for Knutson Creek and concurrent flow data from the Iliamna River and develop an
extended record for Knutson Creek based on the 16.3 years of flow data for the Iliamna River.
The BHC report is included at the end of the feasibility study as Attachment C1.The resulting
extended record provides an improved model of the expected variability of flows in Knutson
Creek that can be used for hydroelectric generation or that must be kept in the creek for
environmental reasons. Using this extended record produces a better understanding of the
long term variability in performance of the hydro project in helping meet Pedro Bays energy
needs.
Figure C 5 presents daily flow statistics for Knutson Creek based on the extended record.
Figure C 5 Daily Flow Statistics for Knutson Creek Based on Extended Record
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Figure C 6 presents two flow duration curves for Knutson Creek. One curve is based on flow
data for the lower gauging station and the second curve is based on the extended record for
Knutson Creek.
Figure C 6 Flow Duration Curves for Knutson Creek at Proposed Intake Site
0
50
100
150
200
250
300
350
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0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percent of Time Flow is Equalled or Exceeded
Flow Duration Curve for Intake Site, Based on Lower Gauge Data
Flow Duration Curve for Intake Site, Based on Extended Record
Design Flow for Recommended Project
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report C 14
ATTACHMENT C 1
KNUTSON CREEK STREAMFLOW ANALYSIS REPORT
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report C 15
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Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report
APPENDIX D RESOURCE DATA AND ANALYSIS
Section Title Page Nos.
D.1 Maximum Probable Flood........................................................................ D 2
D.2 Review of Climate Effects on Hydropower Projects................................. D 2
D.3 Geotechnical Considerations................................................................... D 4
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 1
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Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 2
D.1 MAXIMUM PROBABLE FLOOD
Determining the maximum probable flood for Knutson Creek is important for (1) designing the
in stream diversion structure at Knutson Creek so it can withstand flood flows, and (2)
designing the creek crossing, powerhouse, and other project features so they are not damaged
by flood events. Existing data from the gauging station are compared with U.S. Geological
Survey (USGS) statistical models for southwest Alaska streams to develop initial estimates of
the 100 year and 500 year flood flows for Knutson Creek (USGS, 2003).
The USGS has developed statistical models to estimate the maximum probable floods for
streams in southwest Alaska. These models are developed based on stream gauging data
throughout the region and specific parameters for the drainage basin of the stream of
interest.14 The USGS model input parameters and estimated flood flows are summarized in
Table D 1. The highest calculated flow in the extended record (1,500 cfs) is approximately 30%
greater than the estimated 15 year flood flow based on the USGS model. This is reasonable
agreement, given the accuracy of the USGS estimation method and the length of record at
these gauging stations. The estimated 500 year maximum probable flood flows are used for
the conceptual designs described in this feasibility study.
Table D 1 Maximum Probable Flood at Knutson Creek
Parameter Knutson Creek Diversion Site
Basin Area (square miles) 29.2
Mean Annual Precipitation (inches)
(1)40
Percentage of Basin as Storage (lakes, ponds) 0%
Estimated 500 year flood 2,423 cfs
Estimated 100 year flood 1,803 cfs
Estimated 10 year flood 1,027 cfs
Maximum Flow in Extended Record (15 years) 1,500 cfs
NOTE:
(1) Data are from source maps specified in the USGS Water Resources Investigation Report 2003 4188 (USGS, 2003).
D.2 FLOOD HAZARDS
Upstream of RM 1.7, Knutson Creek is confined to its general course by bedrock topography.
Minor shifting within the valley floor is possible and appears to occur regularly, but these
meanders will not significantly impact the hydro project improvements. Aside from the
diversion/intake structure, which is located at an exposed bedrock sill, the major project
features that are most exposed to flood or erosion hazards are portions of the upper intake
access road that are located along the westerly fringe of historic meander limits, and the
eastern most penstock bridge pier that is located within the historic meander limits. These
project features will be designed to withstand these flood and scour hazards.
14 See USGS Water Resources Investigation Report 2003 4188 (USGS, 2003).
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 3
From RM 1.7 to its mouth on Lake Iliamna, Knutson Creek flows in an actively moving channel
over an alluvial cone. In the early 1990s, Knutson Creek jumped its easterly bank in the vicinity
of RM 1.00 to 1.30 and flowed down to the airport, causing significant erosion of the runway. A
berm was built along the original creek bank to restore the creek to its original and still current
channel (USACE, 2007). The age of vegetation across much of the cone suggests that Knutson
Creek is not rapidly accreting large volumes of material in this area, however, the cone is not
significantly gullied and Knutson Creeks history of channel shifting indicates the cone remains
subject to Knutson Creeks meanders.
Given the history of the creek and the topography of the alluvial cone, it is conceivable that the
creek will experience major channel meanders during the 50 year life of the hydro project.
Potential impacts of channel meanders to the hydro project are summarized below.
(1) Erosion of the equipment access road from station 66+00 to 86+00. This road is built
on grade and could be easily rebuilt or moved using on site material if washed out in
a flood. The precise road alignment or creek fording locations are not critical, and the
road can be readily adapted to future site conditions. If a future Knutson Creek
channel developed along the west edge of the alluvial fan, the road grade off the
alluvial fan from station 86+00 to 88+00 could need to be relocated to a more
suitable location.
(2) Erosion or strandingof the tailrace. By necessity, the tailrace channel crosses the
area where Knutson Creek flowed toward the airport in the 1990s. A repeat of this
event would damage the tailrace. Alternately, if Knutson Creek meandered to the
west, it could strandthe tailrace, effectively lengthening the tailrace. Corrective
action would depend on the nature of changes and the future location of Knutson
Creek. The tailrace could be easily rebuilt or moved using on site material.
(3) Erosion of the powerhouse site. The powerhouse has been sited at the base of an
approximately 50 foot tall embankment that marks the easterly edge of the alluvial
cone, and downstream of a 20 foot tall terrace that has not been eroded by Knutson
Creek. This location is well shielded from Knutson Creek meanders. The presence of
mature birch and spruce trees in the powerhouse vicinity indicates that Knutson
Creek has not been in this area in at least several decades. A meander toward the
powerhouse site would first jeopardize the airport, likely resulting in corrective action
to rechannelize Knutson Creek before it directly threatened the powerhouse site.
(4) Meander toward the hydro access road. The hydro access road traverses the lower
easterly fringe of Knutson Creeks alluvial fan. A meander toward the hydro access
road would first jeopardize the airport, resulting in corrective action to rechannelize
Knutson Creek away from this area before it threatened the hydro access road.
From 2010 to 2012, Knutson Creek eroded approximately 5 feet of the east bank from
approximately RM 1.25 to RM 1.30 the same general area of the breach in the early 1990s.
This project will help prevent future erosion along the east side of Knutson Creek by improving
access to this area. Improved access will allow for increased monitoring of bank erosion and
will help facilitate timely corrective actions to keep Knutson Creek in its existing channel.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 4
D.2 REVIEW OF CLIMATE EFFECTS ON HYDROPOWER PROJECTS
Long term climate trends can affect precipitation, temperature, snowpack, evapo transpiration,
and related hydrological processes, changing the amount and timing of discharge in local
streams and therefore the amount of energy that a hydro project can generate.
Because the proposed design flow for this project is a relatively small fraction of the mean
annual flow in Knutson Creek, these climate effects are not likely to impact project
performance significantly over its 50 year design life.
D.3 GEOTECHNICAL CONSIDERATIONS
Review of surface conditions suggests that bedrock is unlikely to be encountered along most of
the power line route between the village and the hydro powerhouse site. This route should be
easily trenched for installation of the underground power and communications lines using
conventional equipment and methods. It is noted that bedrock outcrops do occur in the village
and it is possible that bedrock be encountered along the power line route.
The hydro access road to the powerhouse can be readily graded and shaped from on site
materials. Use of non organic on site material may be appropriate for the finish course of the
road prism given the low volume of traffic along the road.
Based on surficial observations, bedrock is unlikely to be shallow enough at the powerhouse
site to be of use for the powerhouse foundation. The location at the top of Knutson Creeks
alluvial cone and the surficial geology suggest that the powerhouse site will likely be a poorly
sorted and fairly course aggregate deposited by Knutson Creek. Test pits are recommended to
verify subsurface conditions at the powerhouse site.
The first bedrock outcrops occur along Knutson Creek approximately ½mile upstream of the
powerhouse site, and continue upstream to the diversion site. Bedrock is inferred to be at or
near the surface throughout this area based on these occurrences. In the immediate vicinity of
the creek, surficial deposits consist of poorly sorted sands, gravels, cobbles, and boulders, with
the largest boulders measuring 6+ feet. An excavator in the 40,000 to 60,000 pound class fitted
with a thumb can efficiently manage most of the boulders in the project work areas.
Bedrock may be encountered along the penstock route, and may require blasting in a few areas
in order to achieve sufficient burial of the pipe. In most areas, it will be more cost effective to
import additional fill than to excavate, rip, or blast the rock. Rock is expected to be shallower
along the upper portion of the penstock route along the west side of Knutson Creek. Blasting
could be necessary in the vicinity of the junction between the penstock and the access road,
where the penstock traverses a saddle area.
Bedrock is exposed at the diversion site. The exposed rock appears to be a competent and
suitable foundation material for a low diversion structure. Subsurface flow underneath the
diversion structure should be minimal because of the presence of this rock.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 5
D.3.1 Area Geomorphology
The Knutson Creek project is located in either the southern extents of the Alaska Range, or
northern extent of the geographically contiguous Aleutian Range, depending on the
nomenclature used by various source documents. The project is located on the northwestern
side of this mountain range which extends from the Alaska Range to the northeast (in the
vicinity of Skwentna and Rainy Pass), and runs southwest, following the west shore of Cook
Inlet and continuing down the southern side of the Alaska Peninsula before transitioning into
the Aleutian Islands.
Bedrock Geology
Bedrock geology of the Iliamna Quadrangle was mapped by the USGS in the late 1960s and
1970s, and is shown for the project vicinity in Figure D 1 (USGS 1980). The Knutson Valley and
surrounding mountains are formed from an intrusive pluton of quartz monzonite that has been
tentatively assigned a late Cretaceous age. The quartz monzonite is a massive coarse grained
light gray prophyritic rock. Samples considered typical of the formation contain approximately
24 percent quartz, 25 percent orthoclase, 46 percent plagioclase, 4 percent hornblende, and
minor accessory minerals. Quartz diorite and granodiorite are present in adjacent formations,
and may occur in bedrock of the project area as well. (USGS, 1980)
Numerous surface presentations of bedrock are visible in Knutson Creek and rock outcrops
along the creek. The material typically has widely spaced joints, and appears very competent.
Most of the boulders, cobbles and sand grains in Knutson Creek are of this same parent rock in
various stages of weathering and decomposition.
Surficial Geology
Surficial geology of the Iliamna Quadrangle was mapped by the USGS in the late 1960s, and is
shown for the project vicinity on Figure D 2 (USGS 1973). Surficial geology in the project area is
predominately flood plain alluvium and alluvial cones in the immediate vicinity of Knutson
Creek. The access road to the powerhouse, powerhouse site, tailrace, and intake site are
located in such areas. Portions of the penstock route and intake access road located on
benches above Knutson Creek are in areas that include talus and rubble deposits from the
surrounding mountain slopes. Surface presentations of these features suggest the deposits and
the up gradient source terrain are all currently vegetated and stable. Most of the mass
movements that created these deposits are attributed to past glaciation or immediate post
glacial periods.
The project is located in a region of sporadic permafrost. Most permafrost occurrences in the
region are characterized as relict permafrost surviving from the colder climate of the last
glaciation (USGS, 1973). The southern aspect and typical surficial geology of the immediate
project area are not favorable to permafrost, but isolated occurrences are possible.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 6
Figure D 1 Bedrock Geology of the Project Area
Detail from Plate 1, USGS Geological Bulletin 1368 B (USGS, 1980)
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 7
Figure D 2 Surficial Geology of the Project Area
Detail from Plate 1, USGS Geological Bulletin 1368 A (USGS, 1973)
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 8
D.3.2 Tectonics and Volcanism
The project site is located midway between two major area faults. The Lake Clark fault, which is
likely a splay of the Castle Mountain fault system, is located approximately 26 miles northwest
of Knutson Creek, and runs in a northeast southwest direction. The Bruin Bay fault, which
generally traces the western shore of Cook inlet, is located approximately 26 miles southeast of
Knutson Creek and also runs in a northeast southwest direction. The Bruin Bay fault in the
vicinity of the project probably has not moved since Oligocene time (23+ million years ago)
(USGS, 1980). The Cottonwood Creek canyon, immediately north of Pedro Bay Village and
normally oriented to the major axis of Knutson Valley, has been identified as a minor local
lineament that may represent a fault, fracture, or joint system (USGS, 1980).
Design of project features in accordance with building codes and accepted engineering practice
is adequate to address seismic activity in the project area.
Several active volcanoes are located in the general vicinity of Knutson Creek. These include
Fourpeaked, Augustine, Redoubt, and Spurr Volcanoes, all of which have erupted in the past
two decades. The closest of these is Augustine, which is approximately 35 miles southeast of
Knutson Creek.
The only notable potential hazard to the project from these volcanoes is ash fall. A significant
ash fall in the Knutson Creek basin could result in suspended ash flowing in Knutson Creek,
which may not be removed by the intake structure. The abrasiveness of the ash could cause
accelerated wear of the turbines water surfaces, shortening its useful life. Also, airborne ash
entering the hydro powerhouse through inadequately filtered ventilation systems could
damage the generator, switchgear, or controls. More severe ash falls would compound these
problems and likely create others as well.
A test pit on Pedro Mountain in the project vicinity encountered three significant ash layers ½
to one inches thick within 20 inches of the ground surface, with the most recent being an
approximately ¾inch thick layer from the 1912 eruption of Katmai / Novarupta Volcano. (USGS,
1973).
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report D 9
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Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report
APPENDIX E ENVIRONMENTAL CONSIDERATIONS
Section Title Page Nos.
E.1 THREATENED AND ENDANGERED SPECIES......................................................................E 2
E.2 FISHERIES AND WILDLIFE.................................................................................................E 2
E.3 WATER AND AIR QUALITY................................................................................................E 5
E.4 WETLAND AND PROTECTED AREAS.................................................................................E 5
E.5 ARCHAEOLOGICAL AND HISTORICAL RESOURCES...........................................................E 6
E.6 LAND DEVELOPMENT CONSIDERATIONS.........................................................................E 6
E.7 TELECOMMUNICATIONS AND AVIATION CONSIDERATIONS ..........................................E 6
E.8 VISUAL AND AESTHETIC RESOURCES...............................................................................E 6
E.9 MITIGATION MEASURES..................................................................................................E 6
Attachment E 1 September 22, 2010 Meeting Record
Attachment E 2 June 9, 2011 Meeting Record
Attachment E 3 Fisheries Survey Report
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report E 1
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Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report E 2
E.1 THREATENED AND ENDANGERED SPECIES
The U.S. Fish and Wildlife Service and National Marine Fisheries Service were contacted about
this project. Both agencies confirmed that the project area is not listed as critical habitat for
any threatened or endangered species.
E.2 FISHERIES AND WILDLIFE
The project does not significantly affect upland habitat areas, so no wildlife impacts are
expected.
Because the proposed project would partially dewater anadromous and resident fish habitat,
Polarconsult consulted with ADF&G at the beginning of the feasibility study to scope out the
resource studies and environmental restrictions that would apply to the project to protect fish
habitat. Polarconsult met with Ronald Benkert of ADF&G on September 22, 2010, and met
again with Ronald Benkert, Monte Miller, Jason Mouw, and Stormy Haught on June 9, 2011.
ADF&G indicated that the project could be permitted, and the key issues would be the level of
study warranted to define fisheries impacts and the proper design of mitigation measures to
protect or compensate for habitat impacts. Records of these meetings are included as
Attachments E 1 and E 2 to this appendix.
In 2012, Polarconsult contracted with Alaska Biological Consulting, Inc. (ABC) to complete an
assessment of fisheries resources in Knutson Creek that may be affected by the hydro project.
ABC conducted more in depth consultations with ADF&G in the summer of 2012, contacting
ADFG personnel (including Dr. Robert Piorkowski, Slim Morstad, Fred West, and Jason Dyle)
regarding design of the fisheries survey performed at Knutson Creek in August 2012, and also
consulting with biologists Slim Morstad (ADF&G) and Dr. Thomas Quinn (University of
Washington) regarding the limiting resources for sockeye production in the Iliamna Lake
system. ABCs full report is included at the end of this section as Attachment E 3. Key findings
are summarized below.
The lower portion of Knutson Creek up to approximately RM 2.1 is anadromous habitat for
Sockeye salmon, and the entire reach of Knutson Creek under consideration for this project is
resident habitat for Dolly Varden.
The project will seasonally reduce flow in approximately one mile of anadromous habitat, from
the proposed tailrace discharge at RM 1.1 upstream to the limit of anadromous habitat at RM
2.1. The project will significantly reduce flow in the bypass reach of Knutson Creek (50%
reduction or more) from approximately mid November through mid April. Flow reductions of
approximately 90% would occur from approximately mid January to early April. During the
summer and fall (approximately mid April to mid November), flow reductions would be minor
to negligible (less than 30% flow reduction). See Figure E 1.
Flow would be maintained in Knutson Creek by tributary flow from numerous minor drainages
and the two major tributaries R1 and L1. Tributary L1 discharges to the bypass reach at RM 2.1,
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report E 3
above anadromous habitat, and Tributary R1 discharges to the bypass reach at RM 1.3,
approximately 0.2 miles upstream of the tailrace. The drainage subbasins for these tributaries
are shown on Figure A 3. Subbasin drainage areas are tabulated in Table E 1. Figure E 1
presents flow at the top of anadromous fish habitat under natural conditions, with the hydro
project without in stream flow reservations (ISFR)s, and with the 6.6 cfs year round ISFR
assumed in this study.
Without any ISFRs, the recommended hydro project is able to meet 100% of existing utility
demand year round. The 6.6 cfs ISFR assumed for this study reduces that performance to
94.5% year round, meaning that the utility would still need to purchase and burn approximately
1,200 gallons of fuel annually. The present value of this fuel expense over 50 years is
approximately $200,000. The 6.6 cfs ISFR also reduces the amount of excess energy that can be
used by interruptible electric heating services, increasing the amount of heating fuel burned in
Pedro Bay Village for space heating. This is estimated at 3,300 gallons of heating fuel annually.
The present value of this fuel expense over 50 years is approximately $570,000, resulting in a
total present worth of the 6.6 cfs ISFR estimated at $770,000.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report E 4
Table E 1 Areas of Knutson Creek Subbasins
Subbasin Subbasin Area
(square miles)
Subbasin as
Percentage of
Diversion Subbasin
Total Upstream
Basin Area
(square miles)
Above hydro project diversion
(RM 2.59 to headwaters)
29.17 100% 29.17
Hydro project diversion to Tributary L1
(RM 2.10 to 2.59)
0.74 2.6% 29.91
Tributary L1
(enters Knutson Creek at RM 2.10)
3.16 10.8% 33.07
Tributary L1 to Tributary R1
(RM 2.10 to RM 1.30)
0.77 2.6% 33.84
Tributary R1
(enters Knutson Creek at RM 1.30)
1.67 5.7% 35.51
Tributary R1 to hydro project tailrace
(RM 1.30 to RM 1.10)
0.19 0.6% 35.70
Hydro project tailrace to Lake Iliamna
(RM 1.10 to 0.00)
1.41 4.8% 37.11
Total Knutson Creek drainage (at Lake Iliamna) 37.11 126% 37.11
E.2.1 Anadromous Habitat
It appears that most of the anadromous habitat in the projects bypass reach is marginal. ABC
estimated the productivity of this one mile reach of Knutson Creek to be approximately 100
returning adult salmon, which may or may not successfully spawn in the bypass reach. By
comparison, the lower mile of Knutson Creek below the project and shores of Knutson Bay
support many 1,000s of sockeye salmon. Off site mitigation appears to be a good option for
addressing impacts to anadromous habitat in the bypass reach. Two options suggested by ABC
include construction of additional highly productive fish ponds near the airport or constructing
the project tailrace channel to provide replacement habitat.
E.2.2 Resident Habitat
Dolly Varden are present throughout the proposed bypass reach of Knutson Creek. ABC
concluded that suggested off site compensatory habitat proposed to mitigate impacts to
anadromous habitat would also address impacts to resident fish habitat.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report E 5
0
10
20
30
40
50
60
70
80
90
100
Jan 1 Feb 1 Mar 3 Apr 3 May 4 Jun 4 Jul 5 Aug 5 Sep 5 Oct 6 Nov 6 Dec 7
Proposed Design Flow, cfs
ExistingMean Daily Flow
Bypass Flow with 6.6 cfs ISFR
Bypass Flow with no ISFR
Figure E 1 Estimated Knutson Creek Flow at RM 2.1 (Top of Anadromous Habitat)
ISFR: in stream flow reservation RM: river mile cfs: cubic foot per second
E.3 WATER AND AIR QUALITY
The project will not negatively impact water or air quality. By reducing diesel combustion in
Pedro Bay, the project will improve local air quality. By reducing the amount of fuel shipped to
Pedro Bay for power generation, the project will also incrementally reduce the risk of fuel spills
that could degrade water quality.
E.4 WETLAND AND PROTECTED AREAS
The diversion and intake structures are by necessity located within the ordinary high water
mark of Knutson Creek. The creek bed at the proposed diversion structure is a combination of
exposed bedrock, cobbles, and boulders.
The penstock route passes near some wetland terraces between approximately station 16+00
and 26+00 and may have some unavoidable wetland impacts. Other project features do not
pass through significant wetland areas although some small unidentified wetlands may exist
along the proposed routes. Many of these small wetland areas can likely be avoided in final
design once they are identified.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report E 6
E.5 ARCHAEOLOGICAL AND HISTORICAL RESOURCES
No archeological or historical resources are known to exist in the project area.
E.6 LAND DEVELOPMENT CONSIDERATIONS
The proposed access road to the powerhouse site will provide improved vehicular access to
undeveloped property north of the airport. The proposed power line route will extend electric
service to undeveloped property along the airport access road, as well as undeveloped property
along the hydro access road up to the powerhouse site. These improvements will help to
reduce the cost of developing this land. Some of this land may be subject to flood hazards from
Knutson Creek.
E.7 TELECOMMUNICATIONS AND AVIATION CONSIDERATIONS
The project will not affect telecommunications or aviation.
E.8 VISUAL AND AESTHETIC RESOURCES
The project will not be visible from popular vantage points on the ground surrounding Pedro
Bay Village. The only vantage point from which the project will generally be visible is from the
air.
E.9 MITIGATION MEASURES
Based on current information, total wetlands impacted by this project will likely be under ½
acre. No mitigation is expected to be necessary for this acreage of wetlands impact.
The project will reduce flow in the bypass reach of Knutson Creek by 50% and more during the
winter months (approximately mid November through mid April). This will impact resident and
anadromous fish habitat in Knutson Creek.
Mitigation options for these potential impacts include a minimum ISFR for the anadromous
portion of the bypass reach of Knutson Creek, construction of off site compensatory habitat to
make up for lost habitat in Knutson Creek, or payment as mitigation as allowed in AS 16.05.851.
These options are discussed in greater detail in the fisheries report included as Attachment E 1
to this appendix.
Based on available information, it appears that construction of compensatory habitat is the
most appropriate mitigation measure for this project. ISFRs would decrease generation
capacity during the winter months, when the need for affordable energy in Pedro Bay is
greatest. Similarly, annual payments would place undue financial stress on the community.
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November 2013 Final Report Appendix E
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Pedro Bay Village Council
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November 2013 Final Report Appendix E
ATTACHMENT E 1
POLARCONSULT MEETING RECORD
SEPTEMBER 22, 2010 MEETING WITH ADF&G
Pedro Bay Village Council
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November 2013 Final Report Appendix E
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polarconsult alaska, inc.
ENGINEERS - SURVEYORS - ENERGY CONSULTANTS
specializing in energy conservation systems
CONVERSATION RECORD
DATE: PROJECT: TIME:
September 22, 2010 10002-Pedro Bay Feas 9:00 AM
CONTACT: COMPANY:
Ron Benkert Adfg
PHONE#: FAX#: Taken By:
267-2113 Joel Groves
SUBJECT:
Knutson Creek Hydro
SUMMARY:
Met w/ Ron at his office to review proposed project.
Existing data: ADFG had field crews in the area this summer, they may have done more
fish studies on Knutson Creek. Not sure, as they are focused on studies related to Pebble
road work, and the road is down in known habitat on Knutson. He will check and see and
let me know. Their consultants are still in the QA/QC phase and hadn’t released data.
He wasn’t sure what the upper limit of fish habitat was, if it was the designated limit at
200’ elevation contour or if that was just how far past studies had looked. He had
requested the data to see what the basis of the existing habitat delineation is.
On the project, he said that the winter flows were critical to rearing in the habitat reach,
and 80% retained in-stream flow would be a safe number for permitting. Could do less in
the final permitting, 60%, 70%, but would need more studies or analysis to demonstrate
this would be acceptable to fish habitat. 20% is likely not viable.
Would need more fish studies to better determine the upper limit of habitat. Main
question to be answered is if the intake area is habitat. If so, then fish screens at the
intake would be necessary.
He pointed out that negative fish trapping results weren’t always conclusive. They’ve
seen some creeks where fish are intermittently present, and may come and go from year
to year.
I mentioned our intent to install a gauge, he said this would be useful data, as well as
more pictures of the project area and the habitat in Knutson Creek in the project vicinity.
Also discussed tributary ‘R1’. He concurred that it would likely be easier to permit,
based on the apparent higher gradient and presumed lack of fish habitat. This would still
need to be verified with trapping.
He noted that R2 and HDR both are familiar with the area for fish work. Also mentioned
that ballpark numbers for dolly varden and sculpin are that they are not present in creeks
above 20% grade.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report Appendix E
ATTACHMENT E 2
POLARCONSULT MEETING RECORD
JUNE 9, 2011 MEETING WITH ADF&G
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report Appendix E
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polarconsult alaska, inc.
ENGINEERS - SURVEYORS - ENERGY CONSULTANTS
specializing in energy conservation systems
CONVERSATION RECORD
DATE: PROJECT: TIME:
June 9, 2011 10002 3:45 PM
CONTACT: COMPANY:
Ron Benkert Adfg
PHONE#: FAX#: Taken By:
Joel Groves
SUBJECT:
Knutson Creek Fish Issues & Project Update
SUMMARY:
Meeting with Ron Benkert (RB), ADFG Habitat. Also present were:
Stormy Haught (SH)
Jason Mouw (JM) (regional sport fish)
Monty Miller (MM) (statewide hydropower coordinator)
Joel Groves (JG) provided a brief overview of polarconsult, other hydro projects
currently underway at Polarconsult.
JG provided overview of project history, current phase and status of study, current
development concept and configuration.
Discussed existing habitat limit. JG stated that the habitat limit indicated in the Fish
Atlas did not seem to have a physical barrier, although there was a potential barrier in the
canyon. There is little apparent valuable habitat above this point, but if fish can make it
here, they can probably keep going upstream.
MM asked about jurisdiction, JG opined that the project was not likely under FERC
jurisdiction. MM felt that it would be because the fisheries resource is Bristol Bay
sockeye, which has a clear interstate commerce status.
RB stated key issues for habitat: screens at the intake (1 mm) and tailrace, and minimum
flows in the bypass reach. Intake screen is a big challenge and cost, icing in particular is
an issue. This is all in flux until some firm data on the resource are available. Habitat
mapping, fish trapping, etc.
RB requested that future hydrographs be linear, not log, so they are easier to interpolate.
Told him that once the hydrology study is done, will provide a better characterization and
presentation of proposed flow regimes. Current data is interim.
JG mentioned the fish present in fens on the west side of the alluvial fan (far side of
Knutson Creek from village). MM speculated that these fens could be hydraulically
connected to Knutson Creek, and at risk from a diversion. JG clarified that he observed
the fens to be directly fed by surface drainage from the bluffs along the west edge of the
alluvial fan. A surface connection to the main channel of Knutson Creek wasn’t
polarconsult alaska, inc.
ENGINEERS - SURVEYORS - ENERGY CONSULTANTS
specializing in energy conservation systems
observed, but probably existed downstream where the fens presumably exit to Knutson
Creek or perhaps directly to the lake. JG did not hike down to these areas.
JM provided an overview of the typical assessment process:
1. Habitat mapping to understand what is out there.
2. Habitat utilization to understand what is using the habitat. Spatial and temporal.
3. Transects and similar analysis to understand what impacts dewatering the habitat
reaches may have on fisheries.
Unclear at this time how far down this progression the study would need to go. If field
work indicates little spawning habitat, then less study, and so on.
RB stated that ADFG was unable to do any trapping or field work in support of this
project. They might be able to do some work under contract, but he wasn’t sure
(potentially less costly than a contract biologist).
JM mentioned that University of Washington has been doing work on Knutson Creek for
years, and may have some data that is pertinent to this project. Contacts are Tom Quinn
and Dan Schlinder.
Preliminary assessment is that this project looks doable, but need field data and analysis
to make a final determination.
Talked about timing of in stream work. Generally, the window is 6/1 to 7/15. Earlier
JVs are out-migrating, and later adults are in-migrating. This would pertain to equipment
fording of the creek. Intake work would have to occur in March/April to avoid high
water. Intake area would be dewatered so no fish impacts expected.
Mentioned bridge crossing, said that expected to keep supports above OHW to avoid
flood hazards, so habitat permit may not be necessary.
(?) indicated that standard guidance for minor creek crossings was 48” dia culvert or
provide 1.2x bank full width in culvert or under bridge.
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November 2013 Final Report Appendix E
ATTACHMENT E 3
FISHERIES SURVEY REPORT
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November 2013 Final Report Appendix E
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Technical Report No. 12-011
__________________________________________________________
A Fisheries Survey of Upper Knutson Creek Associated with Potential
Hydroelectric Development for Pedro Bay, Alaska
INTRODUCTION
Catalog of
Waters Important for Spawning, Rearing, and Migration of Anadromous Fishes (2012)
OBJECTIVES
METHODS
Oncorhynchus nerka
Salvelinus malma
RESULTS
Resident Fish
Cotus sp
Anadromous Fish
Catalog of Waters Important for Spawning, Rearing, and Migration of Anadromous Fishes (2012)
Fisheries Use
General Habitat Observations
DISCUSSION
Fisheries
Mitigation
Resident Fish
Anadromous Fish
LITERATURE CITED
Table 1. Summary of minnow trap catch results in total number of fish, and average
hourly catch by locaƟ on, date, and species, Knutson Creek, near Pedro Bay, 2012.
TRAP Dates Total TOTAL CATCH Avg. Hourly
# LOCATION Fished Hours DOLLY other Catch
VARDEN Dolly Varden
T-1* N 59 48.786 8/23/2012 7.77 39 0 5.0
W 154 07. 361
1 N 59 48.846 8/23/2012 6.75 71 0 10.5
W 154 07. 341
2 N 59 49.069 8/23/2012 5.72 34 0 5.9
W 154 07. 039
3 N 59 49.146 8/23/2012 4.90 6 0 1.2
W 154 06. 889
4 N 59 49.172 8/23/2012 4.00 34 0 8.5
W 154 06. 850
5 N 59 49.195 8/23/2012 3.47 19 0 5.5
W 154 06. 870
6 N 59 49.204 8/23/2012 2.65 14 0 5.3
W 154 06. 789
7 N 59 49.507 8/24/2012 0.87 17 0 19.5
W 154 06. 502
8** N 59 49.598 8/23/2012 0.38 1 0 2.6
W 154 06. 403 8/24/2012 ** 1 0 **
9 N 59 49.598 8/23/2012 0.22 6 0 27.3
W 154 06. 403 8/23-24/2012 21.25 14 0 0.7
TOTALS 57.98 256 0 Average 8.4
* Site in lateral tributary 50yds upstream of Knutson Cr. confluence
** Trap dislodged from site found x-wise in stream
Table 3. Sampled fork lengths (cm) of Dolly Varden captured, by selected minnow
trap, in upper Knutson Creek, an Iliamna Lake inlet stream near Pedro
Bay Village, 8/23-24/2012.
Specimen Trap Trap Trap Trap Trap Trap Trap
Number # 2 # 3 # 4 # 5 # 6 # 8 # 9
1 6.4 11.9 8.6 14.2 10.4 15.9 15.2
2 10.2 10.9 10.7 15.2 14.2 11.4 14.2
3 9.9 14.0 10.2 11.9 13.7 13.2
4 10.9 12.7 11.4 10.7 11.9 12.2
5 10.4 13.7 12.7 14.7 12.7 11.2
6 9.7 12.4 12.2 15.0 9.9 11.2
7 10.9 11.9 13.5 9.7 13.0
8 11.7 13.2 11.7 10.2 11.4
9 6.9 12.7 13.5 10.9 12.7
10 13.2 11.7 11.9 7.4 17.0
11 7.4 16.3 8.9 12.4 13.5
12 9.9 11.7 15.0 11.4 16.8
13 9.4 13.2 11.2 15.2 11.4
14 12.2 19.3 10.9 15.7 15.0
15 11.2 13.7 11.7 12.4
16 15.5 13.0 11.4 12.2
17 14.5 11.7 12.2 12.4
18 11.7 11.4 10.2 13.7
19 5.8 13.7 5.8 12.7
20 12.2 14.7 14.7
21 11.7 15.5
22 12.4 13.2
23 13.0 11.9
24 11.4 9.4
25 10.2 8.6
26 10.9 9.1
27 9.4 12.2
28 10.7 11.7
29 8.6 11.9
30 10.9 12.2
31 8.9 12.7
32 10.2 7.4
33 15.5 9.1
34 8.9 12.7
Table 4. Selected length (FL) staƟ sƟ cs on Dolly Varden sampled on upper
Knutson Creek, an Iliamna Lake inlet stream near Pedro Bay Village
August 23-24, 2012.
Sample Size Mean Median Range Standard
(n) cm inches cm inches cm inches deviaƟ on
(mm)
129 11.9 4.7 11.9 4.7 (5.8 - 19.3)(2.3 - 7.6) 2.3
Pedro Bay Village Council
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November 2013 Final Report Appendix F
APPENDIX F PERMITTING INFORMATION
Section Title Page Nos.
F.1 Federal Permits........................................................................................ F 2
F.2 State of Alaska Permits............................................................................ F 2
F.3 Local Permits............................................................................................ F 4
F.4 Other Permits and Authorizations........................................................... F 5
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F.1 FEDERAL PERMITS
F.1.1 Federal Energy Regulatory Commission (FERC)
The Federal Energy Regulatory Commission (FERC) has jurisdiction over hydroelectric projects
that meet certain criteria. Generally, these criteria include:
(1) The project is located on navigable waters,
(2) The project is located on federal land,
(3) The project affects interstate commerce, or
(4) The project is part of an interstate electrical grid.
None of the information identified by this study indicates the project meets any of these
criteria. The project reach does receive an estimated 100 adult sockeye salmon, which are part
of the 2 to 10 million escapement on the Kvichak River and Iliamna Lake system. However, it is
not established that these sockeye successfully spawn in the project reach, and they constitute
a negligible percentage (0.001 to 0.005%) of the Kvichak River escapement. Accordingly, the
project should not fall under FERC jurisdiction. A Declaration of Intention will need to be filed
with the FERC in the permitting phase of the project to verify this jurisdictional analysis.
F.1.3 U.S. Army Corps of Engineers (USACE) Permits
The diversion structure, intake structure, tailrace, and other features of the recommended
project will be located within waters of the United States; therefore, permits from the USACE
will be required. Additionally, some project features or mitigation efforts may impact wetlands,
which will also require a USACE permit. The project may be eligible for a Nationwide Permit
#17 for hydro projects, #39 for commercial and institutional developments, or others. If the
project cannot be permitted under a Nationwide Permit, an individual permit will need to be
obtained instead.
F.1.4 U.S. Environmental Protection Agency
A stormwater pollution prevention plan will be required for construction of the project.
F.1.5 Federal Aviation Administration
The recommended project will not have any features likely to present a hazard to aviation.
F.2 STATE OF ALASKA PERMITS
F.2.1 Alaska Department of Natural Resources (ADNR) Permits
F.2.1.1 Coastal Zone Consistency Review
The State of Alaska does not currently have a Coastal Zone Management Program.
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November 2013 Final Report F 3
F.2.1.2 Land Authorizations
None of the project area is on state land.
F.2.1.3 Tidelands Permits
No tidelands permits are needed for the project.
F.2.1.4 Material Sale Agreement
Not applicable. Material sources likely to be used for this project are not state owned.
F.2.1.5 Water Use Permit/Water Rights
The project will need to obtain water rights from the Alaska Department of Natural Resources
(ADNR).
F.2.2 Alaska Department of Fish and Game (ADF&G) Permits
F.2.2.1 Fish Habitat Permit
The project will need to obtain a fish habitat permit from the ADF&G. The fish habitat permit
will include in stream flow reservations (if any), mitigation requirements, restrictions on
construction activities near and below the ordinary high water mark of Knutson Creek, and
authorization for constructing a creek fording location on Knutson Creek for construction and
on going maintenance access to the upper penstock and diversion / intake site.
F.2.3 Alaska Department of Transportation and Public Facilities Permits
Not applicable.
F.2.4 Alaska Department of Environmental Conservation (ADEC) Permits
F.2.4.1 ADEC Wastewater or Potable Water Permits
Not applicable.
F.2.4.2 Solid Waste Disposal Permit
Not applicable.
F.2.4.3 Air Quality Permit and Bulk Fuel Permit
Not applicable.
Pedro Bay Village Council
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November 2013 Final Report F 4
F.3 LOCAL PERMITS
The project is located within the Lake and Peninsula Borough. A development permit will be
required from the Lake and Peninsula Borough for the project.
F.4 OTHER PERMITS AND AUTHORIZATIONS
F.4.1 Material Sales
Locally sourced aggregate material for the project will need to be purchased from the Pedro
Bay Corporation and/or Bristol Bay Native Corporation. An existing quarry at the airport is
likely a suitable material source for road building and related construction work for this project.
F.4.2 Site Access
Property rights for the project footprint will need to be secured in the form of leases,
easements, and right of ways as appropriate. The land in the project area is owned by Pedro
Bay Corporation. Some land in the project area is being held by the Alaska Department of
Commerce, Community, and Economic Development (ADCCED) Division of Community and
Regional Affairs (DCRA) in trust for a future Pedro Bay municipal government. The PBVC may
be able to secure some or all of the required project lands from these trustee holdings.
Pedro Bay Village Council
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November 2013 Final Report F 5
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November 2013 Final Report Appendix H
APPENDIX G COST ESTIMATES AND ECONOMIC ANALYSIS
Section Title Page Nos.
G.1 Project Cost Estimate............................................................................... G 2
G.2 Economic Analysis and Assumptions....................................................... G 2
G.3 Estimated Utility Electric rates with Recommended Project................... G 7
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G.1 PROJECT COST ESTIMATE
The total estimated installed cost of the recommended project is presented in Table G 1. The
estimated costs in Table G 1 assume the project is contracted out for construction.
Table G 1 Cost Estimate for Recommended Project
Cost Item
Cost Estimate
(2012 $)
PRE CONSTRUCTION COSTS (DESIGN, PERMITTING) $293,000
DIRECT CONSTRUCTION COSTS
Access Roads and Trails $370,000
Power and Communications Lines $375,000
Diversion and Intake Structures $259,000
Penstock $743,000
Building Conversions for Interruptible Electric Heating Service $310,000
Powerhouse $700,000
Shipping/Mobilization/Equipment $555,000
TOTAL DIRECT CONSTRUCTION COSTS $3,312,000
Construction Contingency (20%) $662,000
Construction Management/Administration $120,000
Construction Inspection/Engineering $115,000
ESTIMATED TOTAL INSTALLED COST $4,502,000
G.2 ECONOMIC ANALYSIS AND ASSUMPTIONS
Table G 2 presents the life cycle economic analysis of the benefits and costs of the
recommended project. Assumptions used in developing the economic analysis summarized in
Table G 2 are described in this section.
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November 2013 Final Report G 3
Table G 2 Economic Analysis of Recommended Project
NOTES: All dollar values are in 2012 dollars. All present value calculations assume the projects first year of operations is 2016
and are presented as 2012 dollars.
(1) Future prices for power plant and heating fuel in Pedro Bay use the fuel price projections developed by the Institute of
Social and Economic Research (ISER) for the Alaska Energy Authority (AEA) (July 2012).
(2) Gross excess energy is the energy generated at the powerhouse before system losses are subtracted.
(3) Capital cost estimate includes a budget for retrofitting building electrical and mechanical systems to receive interruptible
electric heating service.
(4) The benefits, costs, and benefit cost ratio for a grant financed project are calculated using the ISER economic model
developed for the AEAs Renewable Energy Grant Program Round 6 (July 2012).
Parameter
Recommended
Project
(200 kW)
ECONOMIC EVALUATION OF DEBT FINANCED PROJECT (Relative to continued diesel generation)
PROJECT BENEFITS
Total Annual PBVC Prime Load Supplied by Hydro 174,100 kWh
Resulting Reduction in Utility Fuel Purchases
(5)16,600 gallons
Annual Value of Savings from Reduced Power Plant Fuel Use (first year of operation)
(1)$96,780
Annual Value of Savings from Avoided Diesel Plant Operating and Maintenance Costs $15,000
Salvage Value (at year 50) $0
Present Value of Power Plant O&M and Fuel Savings Over 50 Years $3,185,000
Gross Excess Hydro Energy Dispatched to Interruptible Electric Heating Services
(2)1,090,300 kWh
Resulting Reduction in Heating Fuel Purchases 24,200 gallons
Annual Value of Savings from Reduced Heating Fuel Use (first year of operation)
(1)$136,500
Present Value of Heating Fuel Savings Over 50 Years $4,149,000
PRESENT VALUE OF PROJECT BENEFITS $7,334,000
PROJECT COSTS
Estimated Total Installed Cost of Project (study, permitting, design, and construction)
(3)$4,502,000
Financed Project Cost $4,212,000
Annual Cost of Debt Servicing (for 30 years) $317,600
Estimated Annual Operating, Maintenance, Repair, and Replacement Cost for Hydro
Plant (for 50 years)
$29,000
PRESENT VALUE OF PROJECT COSTS $6,234,000
BENEFIT COST RATIO (Debt Financed Project) 1.18
ECONOMIC EVALUATION OF GRANT FINANCED PROJECT (Relative to continued diesel generation)
PRESENT VALUE OF PROJECT BENEFITS
(4)$8,280,000
PRESENT VALUE OF PROJECT COSTS
(4)$4,132,000
BENEFIT COST RATIO (Grant Financed Project)
(4)2.00
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November 2013 Final Report G 4
G.2.1 Estimated Annual Project Costs
G.2.1.1 General, Administrative, Operation, and Maintenance Expenses
Typical general and administrative costs for a utility like PBVC range from $15,000 to $25,000
per year. This annual expense covers activities such as meter reading, customer service,
managing the utilitys business affairs, etc. These costs will not significantly change if the
means of energy generation changes from diesel to hydro or a combination of the two.
Typical non fuel O&M expenses for a utility like PBVC are also in the range of $15,000 to
$25,000 per year. This annual expense includes the costs of lube oils, filters, and other
consumables for the diesel generators, maintenance labor, and similar costs that are generally
related to the running time of the diesel engines. A significant portion of these costs will be
avoided with the recommended hydro project.
The hydroelectric project will have additional O&M costs. This includes additional labor costs
for monitoring and maintaining the hydro systems as well as direct expenses for parts and
consumables. Annual O&M costs for the recommended project will be approximately $10,000
to $20,000 per year. This will include activities such as plant inspections, maintenance, routine
parts replacement, and trail maintenance costs.
G.2.1.2 Repair and Replacement
Most of the hydroelectric project systems and components have a very long useful life. The
intake, penstock, powerhouse, switchgear, turbine/generator, and power line all are expected
to have useful lives of 30 to 50 years or more. Some components will require periodic repair or
replacement. Components such as pumps, actuators, some control system components and
sensors, and bearings are assumed to have a useful life of 5 to 10 years. The water turbines
may need an overhaul after about 15 to 25 years. The average annual expense for repair and
replacement is estimated at $8,000 for the recommended project.
G.2.1.3 Taxes
Because the PBVC is a not for profit entity, no tax liability is considered.
G.2.1.4 Insurance
It is assumed that the PBVCs existing insurance policies will be adequate for the hydroelectric
project. No additional annual costs are allocated for insurance.
G.2.1.5 Financing
Two financing options are considered for the project: (1) debt financing and (2) grant financing.
A combination of these methods may also be used.
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November 2013 Final Report G 5
Debt Financing
For debt financing, the entire construction cost of the project is assumed to be commercially
financed for a 30 year term at 6% interest. Loan origination costs of 3% are assumed for items
such as application fees and loan guarantee fees. State or federal loan programs can lower
PBVCs borrowing costs for the project below market rates, which would reduce annual debt
payments, enabling PBVC to lower electric rates in the community.
Grant Financing
State or federal grants can help reduce the amount of capital PBVC needs to borrow for the
project. Such grants would enable PBVC to further lower electric rates in the community. BCRs
for a fully grant financed project are developed using the economic model developed for the
Alaska Energy Authoritys (AEAs) Renewable Energy Grant Program by the Institute of Social
and Economic Research (ISER).
13
G.2.2 Estimated Project Revenues and Savings
G.2.2.1 Direct Fuel Displacement
The recommended hydro project will significantly reduce the amount of diesel fuel PBVC
consumed for electricity generation. Fuel savings are calculated using recent operating
efficiency and fuel costs for PBVCs diesel power plant of 12.4 kWh per gallon, and the future
fuel price forecast for Pedro Bay prepared for the AEA by the ISER, which starts at $6.47 per
gallon in 2016.
15 Transportation diesel fuel in Pedro Bay cost $6.90 per gallon in the summer of
2012.16
G.2.2.2 Excess Energy
In addition to reducing diesel fuel usage at the power plant, the recommended hydro project
also generates a significant amount of excess energy that is available on an interruptible basis.
This study assumes this energy is dispatched on an interruptible basis to space heating
applications in community buildings and homes.
The economic model for dispatch of this excess energy assumes that 12% of the gross available
excess energy is consumed by the hydro load governor system, station service, and incremental
energy losses on PBVCs distribution system. The remaining 88% is available as net energy
metered to interruptible utility customer loads such as space heating and water heating
applications at a special rate. Annually, 124,000 kWh of this net excess energy (141,000 kWh
gross at generation) is allocated to the school to replace the existing waste heat it currently
receives from the diesel power plant. This energy will also keep the diesel power plant and
15 Alaska Fuel Price Projections 2012 2035. ISER Working Paper 2012.1 and Microsoft Excel Spreadsheet Price
Model (ISER, 2012).
16 Personal Communication with Mr. Ben Foss.
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November 2013 Final Report G 6
engines warm so they are ready to provide backup power should the hydro plant trip off line.
All of the remaining net excess energy is assumed to be made available to interruptible
services, displacing heating fuel that is consumed with an assumed average efficiency of 84%.
The value of this displaced heating fuel is factored into the economic analysis.
G.2.2.3 Environmental Attributes
The environmental attributes (EA) of the recommended project can be marketed nationwide to
earn PBVC additional revenue. The projects EAs would be sold on the voluntary market, where
pricing for EAs varies. Prices were as high as $0.02 per kWh before the financial crisis of 2008.
Since 2008, prices on the voluntary market have stabilized around $0.001 per kWh.
For several years, there has been an effort at the federal level to implement mandatory
purchase of EAs. Such legislation would likely expand the market and stabilize the pricing for
EAs. It is unknown if or when such legislation would take effect, or what the final terms of such
legislation will be.
While EAs from the project are an additional potential revenue stream for PBVC, at current
rates, the cost to certifythe project to sell EAs would likely exceed the revenue from sale of
the EAs. Accordingly, no revenue from EAs is assumed in the base case of the economic
evaluation.
G.2.2.4 Indirect and Nonmonetary Benefits
The recommended hydroelectric project offers significant indirect and nonmonetary benefits in
addition to direct economic benefits. These other benefits include:
Reduced air pollution (nitrogen oxide [NOx], sulfur oxide [SOx], particulates, and
hydrocarbons) due to decreased operation of the diesel power plant
Reduced noise in Pedro Bay when the diesel plant is turned off.
Reduced risk of oil spills due to decreased throughput and handling of fuel.
More stable energy prices. With a hydro plant, PBVCs electricity rates will be largely
insulated from the increasingly volatile world oil prices.
Secondary benefits arising from the availability of plentiful hydroelectricity with a stable
price. This will increase the affordability of living and doing business in Pedro Bay and
will help to increase the long term viability of the community. An example of such a
secondary benefit is an increase in the population of school age children, helping the
village to reopen the school and ensuring that school enrollment exceeds district and
state thresholds for state funding year to year.
Economic multipliers due to the fact that a greater percentage of the utility's revenues
will be retained in the local community for labor instead of paying external entities such
as fuel suppliers.
Pedro Bay Village Council
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November 2013 Final Report G 7
Local training and experience with small hydroelectric projects. To the extent that local
residents choose to be involved in construction, maintenance, and operation of the
hydroelectric project, they will learn a unique set of skills. These skills will become
increasingly useful as Alaska continues to develop its local hydroelectric resources.
G.3 ESTIMATED UTILITY ELECTRIC RATES WITH RECOMMENDED PROJECT
There are numerous pricing models that electric utilities can adopt, and a detailed discussion of
those models is beyond the scope of this report. This section provides a simple analysis of
estimated utility costs and rate requirements under basic financing scenarios for the
recommended project. Because the recommended project assumes significant energy sales on
an interruptible basis, potential rates include interruptible energy sales. Table G 3 summarizes
estimates electric rates with the recommended project under debt and grant financing
scenarios.
Table G 3 projects an electric rate of between 6.5 and 125.5 cents per kWh for normal electric
service and 6.5 and 19.8 cents for interruptible electric service, depending on how the
recommended project is financed.
Pedro Bay Village Council
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Table G 3 Estimated Electric Rates with the Recommended Project
Parameter Recommended
Project (200 kW)
ESTIMATED ENERGY PERFORMANCE OF RECOMMENDED PROJECT
Total Annual PBVC Prime Load Supplied by Diesel (kWh) 8,100 kWh
Total Annual PBVC Prime Load Supplied by Hydro (kWh) 174,100 kWh
Total Annual PBVC Prime Load (kWh, at generation) 180,200 kWh
Total Hydro Energy Dispatched to Supply PBVC Prime Load (kWh) 174,100 kWh
Total Gross Excess Hydro Energy Available (kWh)
(1)1,329,600 kWh
Gross Excess Hydro Energy Dispatched to Interruptible Electric Heating Services (kWh) 1,090,300 kWh
Percentage of Community Building Heating Needs Supplied by Hydro Energy
(2)86%
Percentage of Home Heating Needs Supplied by Hydro Energy
(2)56%
Remaining Excess Hydro Energy (kWh) 239,300 kWh
Total Annual Hydro Generation (kWh) 1,503,700 kWh
ESTIMATED ELECTRIC RATES WITH DEBT FINANCED HYDRO PROJECT
Estimated Total Installed Cost of Project (study, permitting, design, and construction) $4,502,000
Financed Project Cost $4,212,000
Annual Cost of Debt Servicing $317,600
Annual Utility Fuel Cost $4,200
Annual General and Administrative Cost $20,000
Annual Hydro Plant Operations, Maintenance, Repair and Replacement Cost $29,000
Annual Diesel Plant Operations and Maintenance Cost $5,000
Operating Margins (Contingency) $15,000
Annual Revenue Requirement $390,800
Electric Service Type Sales Volume (kWh) Estimated Rate ($/kWh) Annual Revenue
Prime Energy Services 160,150 $1.255 $201,040
Interruptible Heating Services 958,400 $0.198 $189,760
Total 1,118,550 $390,800
ESTIMATED ELECTRIC RATES WITH GRANT FINANCED HYDRO PROJECT
Annual Revenue Requirement
(3)$76,400
Electric Service Type Sales Volume (kWh) Estimated Rate ($/kWh) Annual Revenue
Prime Energy Services 160,150 $0.065 $10,410
Interruptible Heating Services 958,400 $0.065 $72,710
Total 1,118,550 $78,470
CURRENT ELECTRIC RATE (FOR COMPARISION) $0.91 per kWh
CURRENT EQUIVELENT COST OF HEATINGFUEL FOR BUILDINGS $0.22 per kWh
NOTES: All dollar values are in 2012 dollars. PBVC load and hydro performance based on assumptions detailed in Appendix H.
Economic assumptions are detailed in Appendix G.2.
(1) Gross excess energy is the energy generated at the powerhouse before system losses are subtracted.
(2) See Section H.2.3 for discussion of the assumptions used for interruptible electric heating services.
(3) Same revenue requirement as for the debt financed project but without the debt servicing cost
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November 2013 Final Report G 9
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November 2013 Final Report Appendix H
APPENDIX H TECHNICAL ANALYSIS
Section Title Page Nos.
H.1 Hydro Project Modeling........................................................................... H 2
H.2 Project Sizing Analysis.............................................................................. H 8
H.3 Evaluation of In Stream Flow Reservations........................................... H 12
H.4 Different Utility Load Scenarios............................................................. H 13
H.5 Load Growth Scenarios.......................................................................... H 12
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November 2013 Final Report H 2
H.1 HYDRO PROJECT MODELING
The primary analytical tool used to evaluate various hydro project configurations and load cases
for this feasibility study is a generation dispatch model (GDM). A GDM takes in the technical
parameters of the proposed generation systems (both hydro and diesel), resource availability,
and utility loads, and then simulates operation of the proposed integrated system to determine
how a given hydro project configuration performs.
H.1.1 Generation Dispatch Model (GDM)
The GDM developed for this feasibility study runs at a one day time step and is used to assess
seasonal and annual variations in the performance of various project configurations. Use of a
shorter time step was not warranted because the hydro resource and proposed project
capacity are both sufficient to carry 100% of Pedro Bays existing peak electric load. At this
level of study, short term fluctuations in load and water availability are not significant factors
for the hydro project proposed for Pedro Bay.
At each time step, the model evaluates (1) utility load and (2) available water in Knutson Creek.
If there is sufficient water to supply all of the utility load, the hydro generator is dispatched to
meet 100% of load. If additional water and generating capacity are available, this additional
energy is dispatched to interruptible loads. If there is insufficient water to supply all of the
utility load, the diesel power plant is dispatched to supply all or a portion of the utility load. At
the next time step, this analysis is repeated. Inputs used to develop and run the model are
described in Table H 1.
The model assumes a single crossflow turbine is installed at the hydro powerhouse. When
utility load drops below the minimum operating threshold of the turbine, interruptible loads or
a dump load at the powerhouse are energized to increase load and continue turbine operation.
For project configurations with higher design flows or substantial in stream flow reservations
(ISFRs), the model shuts the hydro project down when there is insufficient water to operate the
turbine at minimum levels.
17
When the GDM calls for the diesel generator(s) to operate, each generator is loaded to a
minimum of 40% of rated output, regardless of the deficit between utility load and hydro
output. Thus, if utility load is 70 kilowatts (kW) and available hydro output is 60 kW, PBVCs 62
kW diesel generator will run at 25 kW (40%), and hydro output will be curtailed from 60 kW to
45 kW. The remaining 15 kW of potential hydro output can be dispatched to interruptible
loads.
17 Other turbine configurations can achieve higher partial flow efficiency than a single crossflow turbine. A series
of pump turbines, or a combination of pump turbines and a smaller crossflow could be appropriate at Knutson
Creek. Final turbine selection should occur during final design, once permit conditions and project capacity have
been determined. These alternate configurations are expected to have slightly increased energy output,
resulting in improved project benefits than those estimated by this study.
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The GDM also monitors utility load and hydro plant availability for opportunities to dispatch
unused hydro plant capacity to interruptible electric heating services for heating buildings in
Pedro Bay. To accurately evaluate these opportunities, generalized building heating demand
was input to the model to estimate how much excess hydro energy could be used for heating
buildings and how much of a buildingstotal energy requirements could be served by
interruptible electric heating services. Assumptions used for this analysis are discussed in detail
in Section H.2.3.
Table H 1 Generation Dispatch Model Variables, Inputs, and Outputs
MODEL INPUT DATA
Input Range of Values Evaluated
Value Used for
Recommended Project
Hydro Project Design Flow (cfs)
10 to 88 cfs
(See Section H.2)
18.25 cfs
Knutson Creek Flow at Diversion
(cfs)
Extended record for Knutson Creek based on
hydrology data for Knutson Creek and
Iliamna River.
Same
In Stream Flow Reservations
0 to 13.3 cfs at diversion site
(See Section H.3)
6.6 cfs at diversion site
PBVC System Demand (kW)
Daily estimate derived from National
Renewable Energy Laboratory (NREL) village
load model and PBVC utility records.
(See Section H.4)
182,200 kWh annual demand
Turbine Efficiency Curve
Standard crossflow turbine efficiency curve,
with peak water to wire efficiency of 62%.
Same
Project Head, Penstock Lengths,
Physical Parameters
Based on field measurements and system
design flows.
Same
Building Data
Square footage and thermal efficiency
estimated from aerial photographs and site
visits.
Same
Climate Data
Average monthly heating degree days for
Iliamna, Alaska.
Same
PBVC Diesel Generator Sizes Based on existing installed equipment. Same
MODEL OUTPUT DATA
PBVC Demand supplied by hydro (daily kWh)
PBVC Demand supplied by diesel (daily kWh)
Excess hydro energy available for interruptible loads (daily kWh)
Excess hydro energy dispatched to heat community buildings (daily kWh)
Percentage of community building heating needs met by hydro energy
Excess hydro energy dispatched to heat homes (daily kWh)
Percentage of home heating needs met by hydro energy
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H.1.2 Load Patterns and Load Model
Table H 2 presents average historical PBVC load data and the simulated load data input to the
GDM. Recent PBVC operating data presented in Table 2 3 and Figure 2 1 (from PCE reports and
PBVC records) was used to determine characteristic loads, and the simulated load model was
developed using a village load simulator tool developed by the National Renewable Energy
Laboratory (NREL).
18
Table H 2 Actual and Modeled Electric Demand
Parameter Typical PBVC Load
(1)PBVC Load Model
Peak Load (kW) ~70 47
Average Load (kW) 21 to 30 21
Total Annual Energy Generation (kWh)180,000 to 296,000 182,200
NOTE:
(1) Based on 2003 to 2013 annual utility system records compiled from PCE program and PBVC records.
H.1.3 Model Results
Average daily hydro performance and PBVC load over a typical year (2007) are shown on Figure
H 1. Figure H 2 shows the annual variations in hydro performance from 1996 to 2011. The data
shown on Figure H 2 correspond to the extended water records for Knutson Creek and the
range of annual system performance tabulated in Table H 3.
18 The Alaska Village Electric Load Calculator, NREL/TP 500 36824, NREL, Golden Colorado, Sept. 2004.
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportH5Daily Energy Demand and Supply(Average Daily kW)Figure H1 Typical Daily Performance of Recommended Hydro Project
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportH6Daily Energy Demand and Supply(Average Daily kW)Figure H2 Annual Performance Of Recommended Hydro Project (1996 through 2011)
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November 2013 Final Report H 7
Table H 3 Expected Range of Annual Performance for Recommended Project
Expected Annual Hydro Generation
Energy Performance Parameter Minimum
(1999)(1)Average Maximum
(2001)(1)
Total Annual PBVC Prime Load Supplied by Diesel (kWh)
(Diesel as % of total prime supply)
35,200
(22.3%)
8,100
(4.4%)
0
(0.0%)
Total Annual PBVC Load Supplied by Hydro (kWh)
(Hydro as % of total prime supply)
147,000
(77.7%)
174,100
(95.6%)
182,200
(100.0%)
Total Annual PBVC Prime Load (kWh at Generation) 182,200 182,200 182,200
Total Hydro Energy Dispatched to Supply PBVC Prime Load 147,000 174,100 182,200
Total Gross Annual Excess Hydro Energy Available (kWh)
(2)1,110,100 1,2329,600 1,504,600
Gross Excess Hydro Energy Dispatched
to Community Building Interruptible Heating Services
(kWh)
(Percentage of heating load supplied by hydro)
451,000
(64%)
603,900
(86%)
702,200
(100%)
Gross Excess Hydro Energy Dispatched
to Home Interruptible Heating Services (kWh)
(Percentage of heating load supplied by hydro)
423,600
(49%)
486,400
(56%)
563,100
(65%)
Remaining Excess Hydro Energy (kWh) 236,100 239,300 239,300
Total Annual Hydro Generation (kWh)
(Percent of average year)
1,257,100
(83.6%)
1,503,700
(100%)
1,686,800
(112.2%)
NOTES:
(1) Utility load is uniform for all years in the simulation, but water availability in Knutson Creek is based on the extended
hydrological record, and varies from year to year. The years in parentheses reflect the calendar year for the reported
project performance.
(2) Gross excess energy is the energy generated at the powerhouse before system losses are subtracted.
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November 2013 Final Report H 8
H.2 PROJECT SIZING ANALYSIS
H.2.1 Introduction
Knutson Creek has sufficient flow to support a significantly larger run of river hydro project
than is needed to supply the PBVC electric systems current load, which has a peak demand of
approximately 70 kW. Undersizing the hydro project will sacrifice an opportunity to support
future growth of the community or serve other energy demands in the community at modest
incremental capital expense. Oversizing the hydro project will result in unnecessary capital
expense that results in no benefit to the community and can also burden the community with
increased operations and maintenance (O&M) expenses over the life of the project. The
challenge in selecting the project capacity is to weigh these considerations evenly to arrive at
the optimalproject capacity. This section presents Polarconsults sizing analysis, which
identifies a 200 kW project as the most economical installed capacity.
This project capacity analysis should be revisited once project permit conditions are finalized
and project designs and cost estimates are more refined to verify that a 200 kW project is
optimalfor Pedro Bay.
A range of project configurations was evaluated using the GDM to determine which hydro
project configuration best supplies PBVCs existing electric load while providing for future load
growth and interruptible energy usage, without unduly impacting project economics. The
primary criteria for this evaluation was displacement of diesel fuel used for generating
electricity and heating fuel for space and water heating in buildings.
Table H 4 lists the range of project parameters that were evaluated using the GDM to assess (1)
the amount of diesel generation displaced by each project configuration and (2) the amount of
excess energy each configuration produced. Findings for key technical parameters are
discussed in the following sections.
Table H 4 Range of Project Design Parameters Considered and Recommended Values
Parameter (1)Range Considered Recommended Project
Hydro Project Installed Capacity 100 to 1,000 kW 200 kW
Hydro Project Design Flow 9 to 88 cfs 18.25 cfs
NOTE:
(1) Related project parameters were also modified in conjunction with the parameters listed. For example, the penstock
diameter was varied with design flow to maintain acceptable head losses.
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H.2.2 Results of Sizing Analysis
Table H 5 summarizes the economics for each of the project configurations considered in this
study using debt based financing and grant based financing. With deployment of interruptible
energy services in the community, the recommended 200 kW project results in the highest BCR
for the project of 1.18 on a debt financed basis and 2.00 on a grant financed basis.
19
19 Debt based financing assumes the entire capital cost is financed over 30 years at 5% interest. Grant based
financing is calculated using the financial model developed for AEA by ISER for the Renewable Energy Grant
Program (Round 6 version, released in July 2012).
Pedro Bay Village CouncilKnutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.November 2013Final ReportH10Table H5 Economic Evaluation of Hydro Project ConfigurationsHydro Project Configuration (Installed Capacity)Parameter100 kW 150 kW 200 kW 250 kW 500 kW 1,000 kWENERGY PERFORMANCE OF PROJECTTotal Hydro Energy Dispatched to Supply PBVC Prime Load (kWh) 180,200 175,100 174,100 171,300 153,900 122,600Total Gross Excess Energy Dispatched to Interruptible Heating Services(1, 2)641,700 932,100 1,090,400 1,167,300 1,153,000 978,500Remaining Excess Hydro Energy 0 61,500 239,200 469,900 1,796,000 3,790,700TOTAL ANNUAL HYDRO GENERATION 821,900 1,168,700 1,503,700 1,808,500 3,101,900 4,891,800ECONOMIC EVALUATION OF DEBTFINANCED PROJECT(Relative to continued diesel generation)PROJECT BENEFITSAvoided Utility Diesel Purchases (gallons)(3)17,200 16,700 16,600 16,300 14,700 11,700Avoided Heating Fuel Purchases (gallons)(3)12,800 20,200 24,200 26,200 25,800 21,400Estimated Savings, Avoided Diesel O&M $15,000 $15,000 $15,000 $15,000 $15,000 $15,000PRESENT VALUE OF PROJECT BENEFITS $5,480,000 $6,665,000 $7,334,000 $7,632,000 $7,279,000 $6,013,000PROJECT COSTSEstimated Total Installed Cost of Project(4)(permitting, design, and construction)$4,195,000 $4,380,000 $4,502,000 $4,816,000 $5,783,000 $6,871,000Estimated Annual Operating, Maintenance, Repair, andReplacement Cost for Hydro Plant$21,600 $23,300 $29,000 $30,600 $37,400 $46,800PRESENT VALUE OF PROJECT COSTS $5,665,000 $5,947,000 $6,234,000 $6,684,000 $8,111,000 $9,754,000BENEFITCOST RATIO (DebtFinanced Project) 0.97 1.12 1.18 1.14 0.90 0.62ECONOMIC EVALUATION OF GRANTFINANCED PROJECT(Relative to continued diesel generation)(5)ESTIMATED PRESENT VALUE OF PROJECT BENEFITS $5,979,000 $7,523,000 $8,280,000 $8,148,000 $7,560,000 $6,202,000ESTIMATED PRESENT VALUE OF PROJECT COSTS $3,851,000 $4,021,000 $4,132,000 $4,420,000 $5,304,000 $6,300,000BENEFITCOST RATIO (GrantFinanced Project) 1.55 1.87 2.00 1.66 1.43 0.98NOTES:All present value calculations assume the projects first year of operations is 2016 and all cost are in 2012 dollars. Detailed assumptions are explained in Section G.2.(1) Gross excess energy is the energy generated at the powerhouse before system losses are subtracted.(2) See Section H.2.3 for discussion of the assumptions used for interruptible electric heating services.(3) Future prices for power plant and heating fuel in Pedro Bay use the fuel price projections developed by ISER for the AEA.(4) Project cost estimate includes a budget for retrofitting building electrical and/or mechanical systems to receive interruptible electric heating service.(5) Estimated benefits, costs, and benefitcost ratio for a grantfinanced project are calculated using ISER economic model developed for the AEA Renewable Energy Grant ProgramRound 6 (July 2012).
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H.2.3 Analysis Methodology for Heating Applications
Electric heating applications would be implemented on an interruptible basis, meaning that
normal electric demand would have a priority over electric heating demand. When total
demand approaches available hydro generating capacity, heating loads would be interrupted
without warning by a central controller to avoid activating the diesel power plant. This
operating scheme is desirable because using diesel fired electricity to heat buildings is less
efficient (and more costly) than using fuel oil to directly heat the building.
The analysis first considered serving public and community buildings, such as the PBVC building,
Village Public Safety Officer (VPSO) office, school, and church. Once these heating loads were
served, significant excess energy remained, so additional service to private homes and buildings
was evaluated. The analysis assumes the 33 homes identified in the 2010 U.S. Census are fitted
for electric heat. Nineteen of these homes are assumed to be occupied and heated year round,
and the remaining 14 are assumed to be occupied and heated from June 1 to September 30.
The relative benefits of just serving community buildings versus community buildings and
homes were reviewed, and in all cases serving homes resulted in an increased BCR. Project
scenarios that consider interruptible heating service also include building mechanical system
retrofits as part of the total project cost. The village distribution system and individual electric
services are assumed to be adequate to handle the increased load of heating service.
Building heating loads were estimated using average monthly climate data for Iliamna, Alaska
(11,030 annual heating degree days at 65 F). The approximate square footage of each of the
community buildings was estimated from aerial photographs and site visits, and a unit heating
load was developed for each building based on these criteria. For homes, a generic model was
developed using similar methods. The resulting heating loads are summarized in Table H 6.
Table H 6 Heating Loads for Community Buildings and Homes
Parameter School
PBVC
Building Church VPSO Office House
Estimated Square Footage 5,500 5,600 5,600 3,600 1,200
Estimated Unit Heating Load
(Btu per hour degree F Sq.Ft)0.32 0.45 0.40 0.40 0.40
Calculated Heating Load
(Btu/hour degree F)
1,760 2,520 2,240 1,440 480
Annual MMbtus 465.9 667.1 593.0 381.2 127.1
Efficiency of Mechanical
Equipment (assumed)
84% 84% 84% 84% 84%
Efficiency of Electric
Distribution System
87.9% 87.9% 87.9% 87.9% 87.9%
Gallons of Fuel Oil to Serve
Space Heating Load
3,960 5,670 5,040 1,480 1,080
Gross Hydro Energy Required
to Serve 100% of Building
Space Heating Load (kWh)
155,300 222,300 197,600 127,000 42,400
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In some cases, the total amount of heating fuel displaced by interruptible electric heating
services is greater than the total amount of heating fuel used by the community (Table 2 1).
More detailed analysis of actual heating fuel usage and heating patterns in the community is
needed to determine the cause of this discrepancy. It is likely that the discrepancy is due to a
combination of several factors, such as a greater portion of heating needs being met with wood
than the assumed 25%, more seasonally occupied homes than assumes, and / or setting
thermostats lower to reduce heating costs.
H.3 EVALUATION OF IN STREAM FLOW RESERVATIONS
Because part of the proposed bypass reach in Knutson Creek is anadromous fish habitat, and
the entire bypass reach is resident fish habitat, it is likely that ADF&G will require an ISFR to
maintain minimum flow in the bypass reach of Knutson Creek. An ISFR will affect hydro project
operations and performance primarily in the late winter months, when flow is lowest.
Construction of off site compensatory habitat is preferable to an ISFR for the project, but an
ISFR is a likely permit condition. ISFR requirements will not be known until PBVC completes
permit negotiations with ADF&G for the project.
Five hypothetical ISFRs were evaluated to determine the impacts of ISFRs on the performance
of the recommended hydro project and other project capacities considered by this study. The
ISFRs and project impacts are summarized in Table H 7.
To provide a realistic forecast of hydro project performance, all analyses of hydro project
performance in this report assume an ISFR of 6.6 cfs unless stated otherwise.
Table H 7 Impacts of In Stream Flow Reservations on Hydro Performance
Hydro Project Capacity and
Percent of Current PBVC Load Supplied by Hydro Project
In Stream
Flow
Reservation
(ISFR)
ISFR as Percentage
of Annual Low Flow
at Diversion Site
(1)100 kW 150 kW 200 kW 250 kW 500 kW 1,000 kW
0 cfs (no
reservation)0% 100% 100% 100% 100% 98.6% 78.2%
4.0 cfs 30% 100% 99.5% 99.2% 98.7% 89.1% 70.8%
6.6 cfs 50% 97.6% 94.7%94.0%92.5% 82.6% 68.6%
10 cfs 75% 89.4% 87.4% 87.1% 84.8% 77.0% 63.6%
13.3 cfs 100% 82.6% 80.8% 80.3% 78.8% 71.4% 59.8%
NOTE:
(1) The annual low flow is the extended record median daily flow at the intake site, which is 13.3 cfs on April 2nd
(see Figure C 5).
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H.4 DIFFERENT UTILITY LOAD SCENARIOS
Performance of the recommended hydro project under different PBVC loads was evaluated
using the GDM for the following load growth cases:
(1) Annual load at 50% of 2008 2010 load,
(2) Annual load at 30% of 2008 2010 load (actual load in 2013),
(3) PBVC load in 2008 2010 (base case),
(4) Annual load at 200% of 2008 2010 load, and
(5) Annual load at 400% of 2008 2010 load.
There is a significant amount of excess energy from the hydro project under all load growth
cases. The amount of excess energy decreases as utility load increases. Under the 400% load
growth case, there is only 573,200 kWh of excess energy available (38.1% of total hydro
generation). Interruptible electric heating services are able to put most of this excess energy
(81% to 97%) to beneficial use under all load growth cases.
Table H 8 Annual Performance of Recommended Project under Load Growth Cases
Expected Annual Hydro Generation
Energy Performance Parameter 50% Load
Reduction
Existing
PBVC Load
(Base Case)
+43%
Load
Growth (2)
+285%
Load
Growth (2)
+570%
Load
Growth (2)
Total Annual PBVC Prime Load Supplied by Diesel (kWh)
(Diesel as % of total prime supply)
7,900
(8.7%)
8,100
(4.4%)
14,200
(5.5%)
33,900
(6.5%)
109,500
(10.5%)
Total Annual PBVC Load Supplied by Hydro (kWh)
(Hydro as % of total prime supply)
83,200
(91.3%)
174,100
(95.6%)
245,800
(94.5%)
486,100
(93.5%)
930,500
(89.5%)
Total Annual PBVC Prime Load (kWh at Generation) 91,100 182,200 260,000 520,000 1,040,000
Total Hydro Energy Dispatched to Supply PBVC Prime Load 83,200 174,100 245,800 486,100 930,500
Total Gross Annual Excess Hydro Energy Available (kWh)
(1)1,420,500 1,329,600 1,257,900 1,017,600 573,200
Gross Excess Hydro Energy Dispatched
to Community Building Interruptible Heating Services
(kWh)
(Percentage of heating load supplied by hydro)
620,300
(88.3%)
603,900
(86.0%)
594,900
(84.7%)
549,100
(78.2%)
377,100
(53.7%)
Gross Excess Hydro Energy Dispatched
to Home Interruptible Heating Services (kWh)
(Percentage of heating load supplied by hydro)
519,500
(60.1%)
486,400
(56.3%)
458,000
(53.0%)
356,700
(41.3%)
181,500
(21.0%)
Remaining Excess Hydro Energy (kWh) 280,700 239,300 205,000 111,800 14,600
Total Annual Hydro Generation (kWh) 1,503,700 1,503,700 1,503,700 1,503,700 1,503,700
NOTES:
(1) Gross excess energy is the energy generated at the powerhouse before system losses are subtracted.
(2) 43%, 285%, and 570% load growth cases correspond to the base case, 200%, and 400% load growth cases in the November
2012 draft report. The headings have been revised to reflect the new base case load based on current PBVC system load in
2012 13.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report
APPENDIX I DRAFT REPORT REVIEW COMMENTS AND RESPONSES
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report I 1
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polarconsul t alaska, inc.
1503 West 33rd Avenue, Suite 310
Anchorage, Alaska 99503-3638
Phone: (907) 258-2420
FAX: (907) 258-2419
M E M O R A N D U M
November 27, 2013 Page 1 of 9
DATE: November 27, 2013
TO: John Baalke, Tribal Administrator, Pedro Bay Village Council
FROM: Joel Groves, Project Manager, Polarconsult
SUBJECT: Response to AEA Review Comments on Knutson Creek Hydroelectric Feasibility
Study and Summary of Other Major Revisions to Final Report
CC: Final Report Appendix I
The Client Review Draft of the Knutson Creek Hydroelectric Feasibility Study Final Report was
provided to the Alaska Energy Authority (AEA) on November 12, 2012. The AEA provided
comments on October 21, 2013.
AEA comments and Polarconsult responses are summarized below. As appropriate, AEAs
comments have been incorporated into the final release of the Knutson Creek Hydroelectric
Feasibility Study Final Report,dated November 2013.
AEA Comments Received October 21, 2013 (Polarconsult responses in BLUE)
The feasibility study recommends a 200 kW run of river hydroelectric project on the main stem
of Knutson Creek. The project would have a design flow of 18.25 cfs, intake at river mile 2.59
and a powerhouse near river mile 1.25. The project reach would affect 1 mile of anadromous
habitat. Total generation is estimated at 1,503,700 kWh, of which 16% would be used to meet
94% of electrical demand and 70% would be used for interruptible space heating. Generation
considers a 6.6 cfs of in stream flow requirements to maintain fish habitat.
1)We are concerned with the recommendation of a project with a bypass reach that affects
anadromous salmon habitat. Knutson Creek is listed for sockeye presence and spawning in
the anadromous waters catalog. Permitting such a project will be lengthy and will require
more fisheries studies than what was done during this feasibility study. It does not appear
ADF&G was consulted on the methodology for the most recent fisheries study. The stream
also contains resident Dolly Varden throughout. In stream flow requirements for fish
passage will be required if the project is permitted and that amount is currently unknown.
ADF&G will have to be consulted and make a determination. It is also unknown if the
project falls under FERC jurisdiction. It may not be worth the time and money to try and
permit a project that may receive permitting requirements that make it unfeasible.
Polarconsult met with ADFG twice over the course of the feasibility study to solicit ADFGs
input on the feasibility of the project, discussing fish related issues and identifying
appropriate measures that may be required to accommodate fish that are present within
the projects bypass reach. The first meeting was with Ronald Benkert on September 22,
2010, and the second with Ronald Benkert, Monte Miller, Jason Mouw, and Stormy
Haught on June 9, 2011.
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 2 of 9
Additionally, Polarconsults fisheries subconsultant Alaska Biological Consulting (ABC)
held further consultations with ADFG in 2012. ABC consulted with ADFG personnel
(including Dr. Robert Piorkowski, Slim Morstad, Fred West, and Jason Dyle) regarding
design of the fisheries survey performed at Knutson Creek in August 2012. Biologists Slim
Morstad and Dr. Thomas Quinn (University of Washington) were also consulted regarding
the limiting resources for sockeye production in the Iliamna Lake system.
Lastly, ADFG Headquarters, Sport Fisheries Division, and Commercial Fisheries Division
were each provided copies of the Knutson Creek Fisheries Report (ABC Technical Report
12 011) in October 2012.
These meetings and consultations have been referenced in the main narrative at Section
3.1, and the meeting records and appropriate correspondence have been added to
Appendix E of the Final Report.
ADFG personnel consulted on this project have indicated that the project can be
permitted. Field surveys to date have quantified potential impacts and identified
potential mitigation measures. The proposed in stream flow reservations and associated
findings in the feasibility study are based on these discussions with ADFG. Additional
consultations with ADFG would occur in the permitting phase of the project to finalize
mitigation measures that are acceptable to both PBVC and ADFG.
In the June 2011 meeting, ADFGs Mr. Miller was of the opinion that the presence of
sockeye within the bypass reach would be sufficient basis for FERC jurisdiction on the
basis of interstate commerce. However, subsequent field surveys in 2012 determined
that the bypass reach receives only approximately 100 spawning sockeye, out of a total
sockeye escapement for the Kvichak River system of 2 to 10 million.
1 It is doubtful that
0.001 to 0.005 percent of a significant interstate commerce activity is sufficient basis for
FERC to assert jurisdiction over the project.
Polarconsult agrees with AEA that the question of FERC jurisdiction is important to the
projects economic feasibility (both in controlling development costs and life cycle
costs/benefits), and recommends that one of the first tasks in the permitting phase of
development be to file a Declaration of Intention with the FERC to determine project
jurisdiction.
Polarconsult also agrees with AEA that continued close consultation with ADFG is
appropriate to insure that environmental constraints on the project do not unduly reduce
its economic benefits to Pedro Bay. Further consultations would occur under the
permitting phase of project development.
2) We question the recommendation for off site mitigation. We do not know of any project in
recent past that has been permitted by ADF&G that allowed off site mitigation for a salmon
1 Fishery Manuscript Series No. 12 04. Review of Salmon Escapement Goals In Bristol Bay, Alaska, 2012. ADFG,
November 2012. Table 3, Page 24. Knutson Creek is a tributary of the Kvichak River.
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 3 of 9
stream. Can you provide an example and the permitting process in regard to cost and time
to complete for such a project? Additionally, since there is much question regarding ADF&G
permitting, Pedro Bay should contact ADF&G and share the feasibility study for their
thoughts to see if it can be permitted as proposed. Monte Miller is the hydro coordinator
for ADF&G and his contact information is attached.
Offsite mitigation is an option under Alaska Title 16 including AS 16.05.871 and 16.05.841.
The legislative intent is to ensure no net loss of anadromous fisheries habitat and
production, and through Title 16 laws there is considerable latitude to mitigate for
anadromous fish habitat impacts by a variety of avenues.
Offsite mitigation under Title 16 is quite common for a variety of projects. One recent
example is the Chuniisax Creek Hydroelectric Project in Atka, which became operational
in December 2012. A deterioriated culvert blocking anadromous fish passage on Dancing
Creek in Atka was replaced as off site mitigation for project impacts to pink salmon
habitat in Chuniisax Creek downstream of the hydro project. Offsite mitigation was also
recently used on the Trunk Road improvement project in the Mat Su Borough. Again,
culvert replacements (on Wasilla Creek and Carneti Creek) were used to mitigate fisheries
impacts along the Trunk Road corridor.
3) Table ES 2: Shows 15.5% supplied by diesel plant as well as 94.5%. Perhaps this is a typo.
This was a typo and has been corrected.
4) Annual kWh generated has dropped from 264,000 in 2008 to 185,000 in 2013. This is a 30%
decrease in five years, which reflects the closing of the school in November of 2010. Table
ES 2 in the report assumes 260,000 kWh of electricity generated.
Figure 2 1, Figure 2 2, and Table 2 3 have been updated to include the latest available
utility data. Annual generation decreased by approximately 10% (year over year) in 2011
and 2012, and 2013 is on track for a similar decrease. These decreases can reasonably be
attributed to the schools closure in fall 2011 and related impacts.
Negative load growth trends are addressed in the sensitivity analysis included in Section
4.4 of the report. While the trends reflected by this loss of load are concerning, the
projects benefit cost ratio remains favorable under current conditions. It is hoped that
the reduced energy costs resulting from the hydro project would help to reverse the
declining population in Pedro Bay, allowing the school to reopen and utility load to
increase. It is noted that Pedro Bays population decreased from 65 in 1970 to a low of 33
in 1980, after the energy crises of the 1970s. By 2000, the population had rebounded to
50. A similar or perhaps more pronounced effect could result from the hydro project.
5) The amount of hydro assumed to be used for heating purposes equals the heating value of
36,000 gallons of diesel, which is significantly more than the 26,870 gallons shown in table
ES 2. The school building and teacher housing are no longer heated according to the school
district, so those heating loads should not be included in the analysis.
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 4 of 9
Polarconsults assumptions used to estimate heating fuel displaced by excess hydro
energy are described in Appendix G, Section G.2.2.2, and are restated below:
1,052,900 kWh Excess hydro energy dispatched to heating loads
x 0.879 combined distribution system losses and energy used by hydro load governor
x 3,414 btu/kWh convert to btus
/ 140,000 btu/gal convert to gallons heating oil
/ 0.84 account for efficiency of typical combustion appliance.
26,870 gallons of fuel oil displaced.
Please note that the excess hydro and displaced fuel oil quantities above are no longer
current as the analysis in the final report has been revised to reflect current PBVC system
load (182,200 kWh) instead of 2008 2011 load of 260,000 kWh.
As builts of the powerplant heat recovery expansion dated September 21, 2013 indicate
that the waste heat service to the school remains in service and the waste heat service to
the teacher housing has been disconnected.
Polarconsult understands that the PBVC is obligated to provide heat to the school building
with waste heat from the diesel powerplant. 141,000 gross kWh (part of the total gross
kWh of excess hydro energy) was budgeted to honor this obligation.No excess hydro
energy was specifically allocated to teacher housing in the study. Given that teacher
housing is configured to receive waste heat from the diesel powerplant, this load could
easily be served by the hydro plant if needed.
6) Section 2.0 Community Profile: The school has been closed. It doesnt appear this has been
considered in the analysis? How does this affect the project benefits? I imagine with the
school closed it does consume near the electricity as when it was open, which would reduce
the hydro project benefits. In a small community the school can be the largest electric and
heat consumer. Has the clinic been closed too?
The report narrative has been revised to acknowledge closure of the school in fall 2011.
The clinic is still open as of November 2013.
7)Section 2.2 Existing Energy System: The switchgear was just upgraded by AEA.
The diesel powerplant upgrades completed by AEA in 2012 & 2013 have been added to
the narrative of Section 2.2.
8) Section 2.2.4 Electrical Distribution System: The distribution system includes a substantial
portion in the lake which causes reactive power. There are reactors installed for power
factor correction. These may need to be upgraded or replaced if the load increases
significantly.
The narrative in Section 2.2.4 has been revised to mention the reactor and system
capacitance associated with the underground cable and submarine cable distribution
system. The need for rebalancing the systems reactance and related matters would be
considered in the design phase of the project. Also, it is unknown if the reactor is
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 5 of 9
currently in service, as the system as builts dated September 2005 indicate the reactor
was not connected at that time. More current system records reviewed by Polarconsult
do not mention the reactor status.
9) Section 2.2.5 Planned Upgrades: According to the 2012 RPSU survey, the two 58kW gensets
have 37k and 42k hours on them. They will need to be overhauled or replaced.
The narrative in Section 2.2.5 has been modified to reflect the need for overhaul or
replacement of these gensets. Current hours for the utility gensets have been added to
Table 2 2.
10)Section 2.2.6 Existing Load Profile: Normally, for northern communities we see higher
winter demands than in the summer. It sounds like this is not the case in Pedro Bay. What is
the higher summer demand attributed to?
Before mid 2011, typical winter time utility generation was roughly 25% higher than
typical summer time utility generation. Since mid 2011, generation has been nearly flat
year round. The Section 2.2.6 narrative has been revised appropriately.
11)Section 2.2.6 Existing Load Profile: Attributes the decrease in total generation in 2009 and
after to conservation efforts and sacrifices. Closing of the school would have a huge impact
on generation needs and this should be noted.
The school closure in 2011 has been added to the narrative in Section 2.2.6.
12)Table 2 3: 2011 and 2012 data needs to be updated.
Table 2 3 and Figure 2 1 have been updated to include more recent electric system data.
13)Section 2.2.8 Population: With the school closing how has that effected population?
The narrative in Section 2.2.8 has been modified to discuss the school closure. Table 2 4
has been revised to include the most recent available population estimates.
14)Figure 2 2: Why do non fuel costs go from approximately 30 cents/kWh to 90 cents/kWh in
Figure 2 2 on the far right? This may be an error, and isnt reflected in PCE data.
The non fuel costs in Figure 2 2 are calculated from monthly PCE data (monthly non fuel
expenses divided by monthly total kWh sales) provided by the AEA. The charted value for
October 2011 just reflects higher than normal non fuel costs for that month.
15)Figure 3 1: Why does the figure show similar home heating loads in Jun Aug as in Oct Nov?
The analysis methodology for heating applications is explained in Appendix H, Section
H.2.3. In summary, of the 33 homes identified in the 2010 Census, 19 are assumed to be
occupied year round and 14 are assumed to be only seasonally occupied (June 1 to
September 30). So while the per building heating load is lower during the summer
months, the total number of buildings being heated during the summer increases from 19
to 33, resulting in a similar total residential heating load year round.
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 6 of 9
16)Section 3.3.3 Access: Knutson Creek is an anadromous stream and will require ADF&G
habitat permits for any vehicles fording the river, during construction and periodic
maintenance. This should be clarified.
The narrative at Section 3.3.3 and Appendix F Section F.2.2 has been revised to clarify this
point.
17)Section 3.3.5 Penstock: Overall penstock length is estimated at 7,080and it is
recommended that the portion of the penstock route deviating from the main access road
will be finished as an ATV trail. This may not be suitable for construction. Installing 2,500of
penstock with light equipment is not feasible.
The narrative at Section 3.3.5 was not intended to imply this trail will only be constructed
as an ATV trail and has been revised for clarity. The trail will be developed as needed to
support installation of the penstock. Post construction, this route will only be suitable for
ATV access to the intake, as the penstock bridge will not be rated for larger vehicles.
Whether the construction trail is left in place or finished as an ATV trail is a detail to be
worked out with the relevant stakeholders in the permitting and design phase of the
project.
18)Section 4.1 Cost Estimate: Believe this number to be a bit low. For example, $191,000 for
16,400of access roads and trails does not seem reasonable based on recently bid hydro
projects. Mobilization costs may actually be twice than the estimate. Lastly, power and
communication lines cost estimate seem light. Rural overhead power lines along existing
roads typically cost $250k $500k/mile, and this is a two mile buried line. Buried line
typically costs about twice what overhead line costs.
Polarconsult has reviewed the project cost estimate and concurs that the line item
estimates for the power line and road construction in the draft report were low. The
project cost estimate and economic analysis have been revised throughout the final
report.
Bid costs for rural projects are notoriously variable, and heavily depend on how the
project is structured for bid and which construction firms bid on the project. The cost
estimate implicitly assumes that the project is organized in an efficient manner, managed
by individuals experienced in the unique logistics of rural Alaska projects, and
competitively bid by a range of qualified contractors.
Available information indicates that geotechnical conditions at the project site are
favorable for road construction. Most of the site is underlain by an aggregate alluvial fan,
which is assumed to be suitable for road construction by shaping on site material with
minimal import or processing of material. As construction equipment capable of building
these roads is available in Pedro Bay, road construction appear suitable for completion
under force account with direct hire of qualified operators.
As mentioned in Section 3.3.1, the powerline route appears suitable for overhead or
underground construction. Existing lines in Pedro Bay are underground, so this practice
was followed for the conceptual designs.
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 7 of 9
AEAs suggested cost metric of $250,000 to $500,000 per mile for rural overhead power
lines is applicable to three phase four wire 7.2/12.47 kV power lines. As Pedro Bay is a
single phase system, this cost metric is not directly applicable. The cost of rural single
phase overhead lines is approximately 75% that of comparable three phase lines, inferring
an appropriate cost metric of $187,500 to $375,000 per mile.
2 The upper end of this cost
range is applicable for lines with adverse geotechnical conditions such as warm silty
permafrost soils that require driven steel piling to support the wood poles.
Geotechnical conditions along the power line alignment in Pedro Bay appear suitable for
direct burial of poles. Accordingly, AEAs suggested cost metric results in an expected cost
for an overhead power line extension of $187,500 per mile, or $351,500 for the power line
extension to the hydro powerhouse. At the current level of study, this cost estimate is
applicable for an overhead or underground power line.
19)Section 4.1 Cost Estimate: Does the proposal include the cost of upgrading the entire
distribution system, service entrances and house electrical and heating systems to allow for
electric heating? The $310,000 estimate ($362,000 found in appendix) only mentions
building conversions. A distribution system analysis may be needed to determine the
capacity of the existing power lines and transformers, and the cost of any needed upgrades.
The budget item for interruptible electric heating services includes installation of a dual
meter base, interruptible service main panel, wiring, and installation of electric heating
equipment. It did not include upgrade of the utility service lines or utility distribution
system.
The existing village distribution system is assumed to have cables with at least #2 copper
conductor, which is adequate to transmit the full 200 kW (~30 amperes) output of the
proposed hydro project. If individual distribution transformers or service lines are
undersized for the additional load of electric heating, the electric heating capacity
installed at that location could be restricted to the capacity of the service, or the service
could be upgraded.
20)Section 4.2 Economic Evaluation: The base case analysis uses 260,000 kWh demand, while
PCE FY13 data shows 185,000 kWh generated (29% less) and 155,000 sold (40% less).
The sensitivity analysis in Section 4.4 addresses the impacts of variations in load from the
260,000 kWh used for the study. Because PBVCs system load has decreased
approximately 30%, the report has been revised where appropriate to acknowledge this
decreased load and discuss how it impacts the project economics.
21)Section 4.2 Economic Evaluation: The grant financed economic analysis scenario may be
valuable to Pedro Bay but is not relevant to AEAs decision making.
2 Comparative costs and cost factors for rural overhead power lines from HVDC Transmission System for Rural
Alaskan Applications, Phase II Prototyping and Testing, Final Report.Polarconsult Alaska, Inc. May 2012. Table
B 1 and associated narrative.
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 8 of 9
No action taken. The grant financedeconomic analysis scenario uses the economic
model developed by ISER and used by the AEA to evaluate grant applications submitted to
the Renewable Energy Grant Program. This has been clarified in the main report
narrative.
22)Page B 8. Photos appear to be identical.
Photograph B 11 has been replaced with the correct photograph.
23)Table C 1. Please clarify what Note 2 is referring to.
Table C 1 Note 2 has been revised.
24)We understand Pedro Bay would like to displace as much diesel fuel as possible; and, unless
there is a reason to assume a sudden change in the trend towards lower electric loads over
time, justifying this project based on higher electric load is not reasonable. With the school
closing and the decrease in population that usually follows it may be more feasible to
permit and design a smaller project that does not affect salmon habitat. There are hydro
projects that operate in conjunction with a diesel plant and have been shown to be feasible.
They contribute to a portion of the communitys generation requirements and still provide
beneficial savings. This may be something that can work for Pedro Bay.
The report narrative has been revised to clarify the report findings with regard to installed
capacity. A project with installed capacity in the range of 100 to 250 kW is best suited to
meet the villages long term energy needs, and the economic analysis identified a 200 kW
project as the most economic installed capacity. The project capacity should be finalized
only after permit conditions are known, and project designs and cost estimates are more
refined.
Projects within the 100 to 250 kW range are technically viable on Knutson Creek. Smaller
projects within this range would reduce, not avoid, partial dewatering of resident and
anadromous fish habitat and the associated habitat impacts. Smaller project capacities
provide modest capital cost and negligible O&M cost savings. As detailed in Table H 5,
downsizing the project from 200 kW to 100 kW reduces the estimated installed cost by
approximately 7% (estimated installed cost decreases from $4.5M to $4.2M). This is
because many of the project costs, such as for pre construction work, mobilization,
shipping, power line, diversion structure, and access roads, do not change with the
decreased project size. The only significant savings come from reduced costs for the
penstock, powerhouse, and turbine/generator.
The current decrease in population is consistent with past fluctuations in Pedro Bays
population, and it is probable that the villages population will continue to track future
economic opportunities in the region. A significant and permanent reduction in electricity
costs from the hydro project will have a clear positive influence on the local economy, and
may result in a rebound in population and utility load. It is not clear that a major
community asset with a 50+ year useful life should be sized based on a 2 3 year transient
P OLARCONSULT M EMORANDUM
November 27, 2013 Page 9 of 9
trend in the local population and utility load. Polarconsult is not aware of any village
hydro project in Alaska that has proven to be over sized over the course of its useful life.
In consideration of these factors, Polarconsult recommends that Pedro Bay proceed with
design and permitting of a 200 kW project, and revisit the matter of installed capacity
once permit conditions are known and designs are more advanced. At that time, the
benefit cost ratio of various configurations should be calculated and the appropriate
project capacity should be selected. Based on available information, it appears that
appropriate installed capacity will be in the range of 100 to 250 kW.
OTHER SIGNIFICANT REPORT REVISIONS
1. The draft report incorrectly included displaced heating fuel for the school building as part of
the total heating oil displaced by the project through interruptible electric heating services.
The school building is currently heated from a waste heat system at the diesel power plant,
and the PBVC is obligated to provide heat to the school. Accordingly, electric heating at the
school displaces waste heat rather than fuel oil, and is not a project benefit. Tables and
narrative throughout the report have been revised to reflect this.
2. Because of the significant decrease in system load that occurred while this report was under
preparation and review, Polarconsult has revised the analysis and final report to reflect the
estimated annual utility load for 2013 of approximately 182,200 kWh, which reflects an
approximately 30% decrease from the 260,000 kWh annual system load that was used in
the draft report. All figures, tables, and narratives reflect this revised system load.
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report
APPENDIX J TABULAR HYDROLOGY DATA
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report J 1
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Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
10/12/2010 23 1.55 1.56 1.59 118 34.40 35.74 37.04 (2)
10/13/2010 48 1.53 1.54 1.56 94 32.79 33.99 35.97
10/14/2010 48 1.51 1.53 1.54 91 31.83 33.25 35.25
10/15/2010 47 1.50 1.52 1.54 91 31.87 33.51 35.38
10/16/2010 48 1.51 1.52 1.53 99 34.24 35.76 36.88
10/17/2010 48 1.51 1.54 1.57 100 36.45 37.19 38.02
10/18/2010 48 1.53 1.54 1.57 103 36.59 37.52 38.76
10/19/2010 48 1.52 1.55 1.58 109 37.30 38.07 39.59
10/20/2010 48 1.55 1.56 1.58 118 37.30 37.96 39.31
10/21/2010 48 1.57 1.69 1.82 127 37.37 37.88 38.14
10/22/2010 48 1.63 1.66 1.73 136 36.92 37.86 39.31
10/23/2010 48 1.58 1.62 1.64 119 37.14 37.85 38.89
10/24/2010 48 1.56 1.58 1.61 112 36.79 37.39 38.24
10/25/2010 48 1.55 1.57 1.59 102 35.90 36.65 37.50
10/26/2010 48 1.53 1.55 1.56 96 35.97 36.81 38.31
10/27/2010 48 1.51 1.53 1.57 115 35.02 35.95 36.91
10/28/2010 48 1.55 1.57 1.61 96 35.25 35.85 36.79
10/29/2010 48 1.51 1.53 1.57 84 34.99 35.63 36.72
10/30/2010 48 1.49 1.50 1.52 78 33.28 34.59 35.58
10/31/2010 48 1.47 1.48 1.50 76 32.06 33.30 34.73
11/1/2010 48 1.47 1.48 1.49 71 34.33 34.81 35.25
11/2/2010 48 1.45 1.46 1.47 68 34.01 34.51 35.22
11/3/2010 48 1.44 1.45 1.47 64 33.88 34.76 35.71
11/4/2010 48 1.43 1.44 1.46 60 32.62 33.37 34.40
11/5/2010 48 1.41 1.43 1.44 56 31.46 32.82 34.01
11/6/2010 48 1.40 1.41 1.43 52 31.53 32.23 33.42
11/7/2010 48 1.38 1.39 1.41 53 31.43 31.60 32.03
11/8/2010 48 1.40 1.62 1.74 51 31.43 31.47 31.51
11/9/2010 48 1.44 1.63 1.93 51 31.40 31.45 31.51
11/10/2010 48 1.39 1.41 1.47 50 31.43 31.66 32.65
11/11/2010 48 1.36 1.38 1.40 46 32.75 33.33 34.10
11/12/2010 48 1.35 1.36 1.37 46 32.39 33.36 34.53
11/13/2010 48 1.35 1.36 1.37 44 32.59 33.18 33.51
11/14/2010 48 1.34 1.35 1.36 44 32.82 33.51 34.23
11/15/2010 48 1.34 1.36 1.46 44 31.43 31.68 32.85
11/16/2010 48 1.47 1.75 1.90 41 31.37 31.45 31.51
11/17/2010 48 1.12 1.22 1.47 38 31.39 31.46 31.53
11/18/2010 48 0.85 0.93 1.10 38 31.42 31.49 31.52
11/19/2010 48 0.97 1.35 2.05 39 31.40 31.47 31.52
11/20/2010 48 1.85 2.19 2.41 44 31.42 31.46 31.52
11/21/2010 48 1.37 1.49 1.89 52 31.43 31.50 31.57
11/22/2010 48 1.36 1.41 1.47 64 31.46 31.64 31.93
11/23/2010 48 1.47 1.67 1.86 76 31.90 33.59 35.22
11/24/2010 48 1.60 1.68 1.86 90 34.73 35.02 35.32
11/25/2010 48 1.50 1.56 1.62 79 31.40 32.65 34.80
11/26/2010 48 1.48 1.49 1.51 86 31.40 31.46 31.50
11/27/2010 48 1.49 1.51 1.53 77 31.47 31.89 32.49
11/28/2010 48 1.47 1.59 1.88 73 31.40 31.66 32.59
11/29/2010 48 1.88 2.12 2.42 70 31.38 31.44 31.51
11/30/2010 48 1.91 2.17 2.50 66 31.39 31.44 31.49
12/1/2010 48 2.02 2.27 2.55 63 31.38 31.44 31.51
12/2/2010 48 2.13 2.31 2.57 60 31.39 31.44 31.49
12/3/2010 48 2.07 2.48 3.25 57 31.39 31.44 31.49
12/4/2010 48 2.26 2.77 3.27 54 31.39 31.46 31.52
12/5/2010 48 1.44 1.68 2.25 48 31.40 31.48 31.57
12/6/2010 48 1.40 1.42 1.44 46 31.43 31.49 31.57
November 2013 Final Report Appendix J Page J 1
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
12/7/2010 48 1.39 1.40 1.41 45 31.43 31.49 31.56
12/8/2010 48 1.37 1.39 1.41 42 31.43 31.47 31.49
12/9/2010 48 1.36 1.37 1.38 40 31.40 31.46 31.49
12/10/2010 48 1.32 1.34 1.37 40 31.40 31.46 31.53
12/11/2010 48 1.32 1.35 1.38 40 31.43 31.47 31.53
12/12/2010 48 1.34 1.35 1.37 39 31.43 31.48 31.53
12/13/2010 48 1.34 1.35 1.36 36 31.46 31.50 31.56
12/14/2010 48 1.31 1.33 1.35 33 31.43 31.48 31.53
12/15/2010 48 1.30 1.31 1.32 32 31.46 31.50 31.56
12/16/2010 48 1.29 1.30 1.32 33 31.46 31.51 31.56
12/17/2010 48 1.28 1.30 1.32 32 31.43 31.52 31.56
12/18/2010 48 1.29 1.29 1.31 33 31.46 31.53 31.56
12/19/2010 48 1.29 1.30 1.31 32 31.49 31.56 31.63
12/20/2010 48 1.28 1.29 1.31 30 31.56 31.62 31.69
12/21/2010 48 1.27 1.28 1.29 29 31.56 31.62 31.66
12/22/2010 48 1.26 1.27 1.28 28 31.53 31.61 31.69
12/23/2010 48 1.25 1.26 1.27 28 31.53 31.60 31.63
12/24/2010 48 1.25 1.26 1.27 27 31.56 31.63 31.69
12/25/2010 48 1.24 1.25 1.27 26 31.60 31.65 31.69
12/26/2010 48 1.24 1.24 1.25 25 31.63 31.69 31.76
12/27/2010 48 1.23 1.23 1.24 24 31.66 31.76 31.86
12/28/2010 48 1.22 1.23 1.24 24 31.69 31.78 31.83
12/29/2010 48 1.22 1.23 1.24 24 31.79 31.96 32.19
12/30/2010 48 1.22 1.23 1.26 28 31.76 32.23 32.49
12/31/2010 48 1.24 1.26 1.30 37 31.53 31.98 32.52
1/1/2011 48 1.24 1.34 1.44 53 31.43 32.02 32.82
1/2/2011 48 1.39 1.45 1.48 40 31.43 31.52 31.69
1/3/2011 48 1.36 1.42 1.57 49 31.63 32.36 33.21
1/4/2011 48 1.41 1.46 1.53 28 31.83 32.56 32.85
1/5/2011 48 1.36 1.38 1.41 22 32.39 32.63 32.89
1/6/2011 48 1.20 1.31 1.36 21 31.40 31.73 32.65
1/7/2011 48 1.14 1.18 1.22 21 31.39 31.45 31.49
1/8/2011 48 1.18 1.23 1.31 20 31.39 31.43 31.46
1/9/2011 48 1.29 1.38 1.45 20 31.40 31.43 31.47
1/10/2011 48 1.42 1.47 1.54 20 31.40 31.43 31.50
1/11/2011 48 1.38 1.46 1.51 19 31.37 31.43 31.50
1/12/2011 48 1.28 1.35 1.47 19 31.40 31.43 31.49
1/13/2011 48 1.31 1.45 1.54 19 31.40 31.44 31.50
1/14/2011 48 1.17 1.25 1.46 18 31.39 31.44 31.49
1/15/2011 48 1.17 1.23 1.30 18 31.36 31.43 31.49
1/16/2011 48 1.05 1.14 1.27 18 31.39 31.45 31.49
1/17/2011 48 1.21 1.34 1.44 18 31.40 31.44 31.50
1/18/2011 48 1.09 1.27 1.46 17 31.36 31.44 31.53
1/19/2011 48 1.46 1.55 1.62 17 31.37 31.43 31.47
1/20/2011 48 1.62 1.70 1.81 17 31.40 31.46 31.51
1/21/2011 48 1.49 1.71 1.83 16 31.40 31.49 31.57
1/22/2011 48 1.30 1.37 1.48 16 31.40 31.47 31.57
1/23/2011 48 1.31 1.34 1.35 14 31.40 31.51 31.60
1/24/2011 48 1.27 1.30 1.34 16 31.49 31.75 32.12
1/25/2011 48 1.25 1.27 1.28 16 32.12 32.57 32.95
1/26/2011 48 1.25 1.26 1.28 15 31.63 32.15 32.52
1/27/2011 48 1.24 1.25 1.27 14 31.43 31.73 32.32
1/28/2011 48 1.22 1.24 1.26 13 32.29 32.64 32.88
1/29/2011 48 1.21 1.22 1.24 12 32.72 32.91 33.11
1/30/2011 48 1.19 1.20 1.22 11 32.88 32.98 33.11
1/31/2011 48 1.18 1.19 1.20 11 32.92 33.03 33.15
November 2013 Final Report Appendix J Page J 2
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
2/1/2011 48 1.18 1.19 1.19 11 32.61 32.80 33.08
2/2/2011 48 1.17 1.18 1.19 11 32.05 32.40 32.55
2/3/2011 48 1.17 1.17 1.18 11 31.99 32.20 32.35
2/4/2011 48 1.15 1.17 1.19 11 31.39 31.64 32.12
2/5/2011 48 1.15 1.16 1.18 12 31.46 31.83 32.22
2/6/2011 48 1.16 1.16 1.17 12 31.82 32.58 33.11
2/7/2011 48 1.15 1.16 1.17 17 32.42 32.83 33.24
2/8/2011 48 1.17 1.21 1.23 16 32.75 33.03 33.21
2/9/2011 48 1.17 1.20 1.22 12 32.91 33.17 33.38
2/10/2011 48 1.15 1.17 1.19 11 31.43 32.16 32.88
2/11/2011 48 1.11 1.40 1.70 11 31.36 31.43 31.47
2/12/2011 48 1.31 1.48 1.60 11 31.37 31.42 31.47
2/13/2011 48 1.57 1.85 2.10 10 31.37 31.43 31.48
2/14/2011 48 1.99 2.31 2.59 10 31.35 31.43 31.49
2/15/2011 48 2.61 2.91 3.07 10 31.37 31.43 31.47
2/16/2011 48 1.24 1.80 2.97 10 31.39 31.47 31.60
2/17/2011 48 1.17 1.19 1.23 10 31.43 31.50 31.60
2/18/2011 48 1.17 1.18 1.20 9 31.46 31.51 31.56
2/19/2011 48 1.16 1.16 1.17 10 31.46 31.51 31.59
2/20/2011 48 1.15 1.15 1.16 10 31.49 31.56 31.62
2/21/2011 48 1.14 1.15 1.16 10 31.56 31.61 31.69
2/22/2011 48 1.12 1.14 1.14 10 31.52 31.62 31.69
2/23/2011 48 1.13 1.13 1.14 10 31.59 31.75 31.95
2/24/2011 48 1.13 1.13 1.13 11 31.79 32.01 32.28
2/25/2011 48 1.12 1.14 1.15 10 31.75 31.95 32.28
2/26/2011 48 1.12 1.13 1.14 10 31.43 31.57 31.79
2/27/2011 48 1.11 1.12 1.13 10 31.43 31.55 31.69
2/28/2011 48 1.11 1.11 1.12 10 31.49 31.55 31.66
3/1/2011 48 1.11 1.11 1.12 9 31.52 31.59 31.69
3/2/2011 48 1.10 1.11 1.11 9 31.52 31.62 31.72
3/3/2011 48 1.10 1.10 1.11 9 31.52 31.61 31.69
3/4/2011 48 1.10 1.10 1.10 9 31.52 31.62 31.72
3/5/2011 48 1.09 1.10 1.10 9 31.52 31.66 31.75
3/6/2011 48 1.09 1.09 1.10 9 31.66 31.77 31.99
3/7/2011 48 1.09 1.09 1.10 9 31.92 32.16 32.38
3/8/2011 48 1.09 1.09 1.09 9 31.99 32.17 32.35
3/9/2011 48 1.08 1.08 1.09 9 31.85 32.08 32.25
3/10/2011 48 1.08 1.08 1.09 8 31.72 31.95 32.12
3/11/2011 48 1.07 1.08 1.08 9 31.62 31.83 31.99
3/12/2011 48 1.07 1.07 1.08 9 31.59 31.75 31.89
3/13/2011 48 1.07 1.07 1.07 8 31.56 31.72 31.89
3/14/2011 48 1.06 1.07 1.07 8 31.59 31.72 31.85
3/15/2011 48 1.06 1.06 1.07 8 31.66 31.82 31.99
3/16/2011 48 1.06 1.06 1.06 8 31.72 31.90 32.05
3/17/2011 48 1.05 1.06 1.06 8 31.62 31.84 32.09
3/18/2011 48 1.05 1.06 1.06 8 32.02 32.34 32.65
3/19/2011 48 1.05 1.05 1.06 8 32.15 32.42 32.65
3/20/2011 48 1.05 1.06 1.06 8 32.38 32.61 32.88
3/21/2011 48 1.04 1.05 1.05 8 32.55 32.77 32.95
3/22/2011 48 1.04 1.04 1.05 8 32.68 32.86 33.04
3/23/2011 48 1.04 1.04 1.05 8 32.75 32.95 33.21
3/24/2011 48 1.04 1.04 1.05 8 32.75 32.98 33.31
3/25/2011 48 1.03 1.04 1.05 8 32.68 33.01 33.41
3/26/2011 48 1.03 1.04 1.04 8 32.68 32.98 33.34
3/27/2011 48 1.03 1.03 1.04 8 32.28 32.68 33.08
3/28/2011 48 1.03 1.03 1.04 8 32.12 32.59 33.01
November 2013 Final Report Appendix J Page J 3
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
3/29/2011 48 1.03 1.04 1.04 9 32.71 33.03 33.37
3/30/2011 48 1.03 1.04 1.05 8 32.84 33.12 33.57
3/31/2011 48 1.03 1.03 1.04 8 32.19 32.60 32.98
4/1/2011 48 1.02 1.03 1.03 8 31.89 32.48 33.08
4/2/2011 48 1.02 1.03 1.04 9 32.68 32.89 33.17
4/3/2011 48 1.03 1.04 1.06 9 32.78 33.06 33.41
4/4/2011 48 1.03 1.03 1.04 8 32.98 33.15 33.47
4/5/2011 48 1.02 1.03 1.03 8 32.52 32.83 33.04
4/6/2011 48 1.01 1.02 1.03 11 31.49 32.05 32.48
4/7/2011 48 1.02 1.06 1.10 10 31.92 32.56 33.01
4/8/2011 48 1.04 1.05 1.06 10 32.65 33.06 33.80
4/9/2011 48 1.03 1.04 1.05 9 32.58 32.98 33.37
4/10/2011 48 1.03 1.03 1.04 9 32.65 32.88 33.08
4/11/2011 46 1.02 1.03 1.03 9 32.65 32.90 33.27
4/12/2011 48 1.02 1.02 1.03 9 32.22 32.67 33.27
4/13/2011 48 1.01 1.02 1.03 9 31.62 32.35 33.08
4/14/2011 48 1.01 1.02 1.02 9 31.66 32.48 33.27
4/15/2011 48 1.01 1.02 1.04 10 32.32 33.11 34.00
4/16/2011 48 1.02 1.04 1.06 11 32.45 33.23 34.10
4/17/2011 48 1.05 1.06 1.09 14 32.48 33.23 34.06
4/18/2011 48 1.08 1.10 1.12 16 32.48 33.22 34.13
4/19/2011 48 1.11 1.12 1.16 19 32.52 33.24 34.16
4/20/2011 48 1.14 1.16 1.18 21 32.35 33.22 34.26
4/21/2011 48 1.16 1.18 1.19 25 32.38 33.15 34.07
4/22/2011 48 1.17 1.21 1.27 55 32.62 33.15 33.67
4/23/2011 48 1.27 1.38 1.52 79 31.60 32.15 32.55
4/24/2011 48 1.43 1.48 1.61 76 31.67 32.69 34.10
4/25/2011 48 1.43 1.48 1.52 57 32.36 33.66 35.84
4/26/2011 48 1.36 1.41 1.49 44 33.02 33.67 34.73
4/27/2011 48 1.32 1.35 1.38 43 33.21 34.91 38.14
4/28/2011 48 1.32 1.34 1.37 45 33.18 33.91 34.66
4/29/2011 48 1.31 1.35 1.41 55 33.84 34.89 36.29
4/30/2011 48 1.39 1.41 1.44 55 33.78 34.96 36.88
5/1/2011 48 1.38 1.41 1.45 57 33.41 35.40 38.30
5/2/2011 48 1.38 1.41 1.45 57 32.42 35.32 40.55
5/3/2011 48 1.40 1.42 1.44 60 33.65 35.63 38.56
5/4/2011 48 1.39 1.42 1.48 69 34.37 35.91 39.49
5/5/2011 48 1.42 1.46 1.51 83 32.85 35.90 40.36
5/6/2011 48 1.45 1.50 1.59 87 33.15 36.17 41.23
5/7/2011 48 1.48 1.51 1.57 82 33.32 35.94 39.43
5/8/2011 48 1.47 1.50 1.53 99 34.66 36.14 38.33
5/9/2011 48 1.50 1.54 1.63 116 34.92 37.09 40.78
5/10/2011 48 1.53 1.58 1.63 106 34.10 37.18 41.96
5/11/2011 48 1.52 1.55 1.60 105 33.05 36.73 41.96
5/12/2011 48 1.52 1.55 1.64 125 33.12 37.20 42.94
5/13/2011 48 1.55 1.59 1.66 132 33.74 37.72 43.13
5/14/2011 48 1.58 1.60 1.65 110 35.58 36.68 38.27
5/15/2011 48 1.54 1.56 1.59 114 35.12 37.37 40.81
5/16/2011 48 1.55 1.57 1.61 133 35.90 37.75 40.30
5/17/2011 48 1.56 1.60 1.71 200 35.87 37.92 41.03
5/18/2011 48 1.67 1.70 1.76 223 35.48 37.93 41.74
5/19/2011 48 1.67 1.72 1.81 307 35.91 38.01 40.94
5/20/2011 48 1.73 1.80 1.88 224 35.61 36.56 38.31
5/21/2011 48 1.68 1.72 1.79 219 35.29 37.58 41.83
5/22/2011 48 1.66 1.72 1.90 285 35.48 37.96 42.28
5/23/2011 48 1.71 1.78 1.88 240 35.88 37.16 38.47
November 2013 Final Report Appendix J Page J 4
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
5/24/2011 48 1.69 1.74 1.80 221 36.13 37.30 38.76
5/25/2011 48 1.67 1.72 1.80 265 35.87 38.21 42.34
5/26/2011 48 1.67 1.76 1.89 364 35.42 38.67 42.38
5/27/2011 48 1.74 1.86 1.99 418 36.34 38.67 43.23
5/28/2011 48 1.82 1.90 2.01 351 35.59 37.89 41.39
5/29/2011 48 1.74 1.83 1.97 413 35.91 38.09 41.49
5/30/2011 48 1.82 1.91 2.04 35.88 39.18 44.41 (1)
5/31/2011 48 1.92 2.01 2.19 36.59 37.82 39.25 (1)
6/1/2011 48 1.96 2.09 2.24 445 36.14 37.06 38.19
6/2/2011 48 1.85 1.98 2.14 35.29 39.01 44.56 (1)
6/3/2011 48 1.92 1.99 2.18 463 36.56 38.26 41.84
6/4/2011 48 1.83 1.93 2.02 424 36.63 37.58 38.70
6/5/2011 48 1.83 1.88 1.96 372 36.43 38.42 41.42
6/6/2011 48 1.78 1.84 1.91 399 35.46 38.54 41.80
6/7/2011 48 1.81 1.87 1.98 448 37.63 39.81 43.68
6/8/2011 48 1.83 1.91 1.97 415 37.41 39.05 40.91
6/9/2011 48 1.83 1.88 1.95 452 37.28 39.32 41.33
6/10/2011 48 1.85 1.90 1.99 428 37.86 39.25 41.36
6/11/2011 48 1.82 1.89 1.95 441 37.37 38.76 40.34
6/12/2011 48 1.81 1.88 1.93 392 38.18 39.46 41.13
6/13/2011 48 1.82 1.86 1.92 383 37.83 39.39 41.13
6/14/2011 48 1.79 1.85 1.90 322 37.86 39.62 42.47
6/15/2011 48 1.74 1.81 1.86 346 37.73 40.42 44.02
6/16/2011 48 1.74 1.82 1.89 353 37.89 40.93 45.09
6/17/2011 48 1.76 1.83 1.92 316 38.05 41.72 46.88
6/18/2011 48 1.76 1.80 1.86 318 38.21 41.45 44.90
6/19/2011 48 1.76 1.80 1.90 426 39.86 40.75 41.77
6/20/2011 48 1.81 1.88 1.94 475 39.31 40.45 41.90
6/21/2011 48 1.88 1.95 2.04 430 39.05 40.30 42.19
6/22/2011 48 1.81 1.90 2.00 387 38.76 40.28 42.69
6/23/2011 48 1.79 1.85 1.94 430 37.34 41.94 47.85
6/24/2011 48 1.82 1.89 1.99 430 40.37 42.86 46.20
6/25/2011 48 1.82 1.89 1.99 416 40.17 41.46 42.76
6/26/2011 48 1.82 1.88 1.96 477 40.17 42.84 46.38
6/27/2011 48 1.90 1.96 2.04 463 40.91 42.21 44.34
6/28/2011 48 1.86 1.93 2.02 391 39.51 40.22 41.40
6/29/2011 48 1.80 1.85 1.90 385 39.24 42.12 47.69
6/30/2011 48 1.81 1.85 1.91 377 40.72 43.20 46.88
7/1/2011 48 1.80 1.84 1.90 360 41.32 43.86 47.41
7/2/2011 48 1.78 1.83 1.90 320 41.36 42.58 44.05
7/3/2011 48 1.77 1.81 1.86 291 41.10 43.64 47.44
7/4/2011 48 1.76 1.79 1.81 288 41.87 43.04 44.81
7/5/2011 48 1.74 1.78 1.86 354 41.10 44.61 49.71
7/6/2011 48 1.78 1.83 1.89 312 42.73 45.36 49.16
7/7/2011 48 1.75 1.80 1.87 256 42.09 43.54 45.03
7/8/2011 48 1.72 1.76 1.80 304 41.68 43.56 46.72
7/9/2011 48 1.73 1.80 1.86 288 42.22 43.08 44.12
7/10/2011 48 1.74 1.78 1.82 295 41.90 43.07 44.56
7/11/2011 48 1.75 1.84 1.99 463 42.76 44.11 45.16
7/12/2011 48 1.88 1.93 2.01 328 42.00 42.92 44.25
7/13/2011 48 1.76 1.81 1.90 259 40.94 42.42 44.40
7/14/2011 48 1.73 1.76 1.80 256 41.45 42.35 43.45
7/15/2011 48 1.73 1.76 1.79 239 41.42 43.51 46.88
7/16/2011 48 1.70 1.74 1.78 264 42.91 44.11 46.82
7/17/2011 48 1.71 1.76 1.89 317 42.82 43.69 44.65
7/18/2011 48 1.76 1.81 1.91 265 42.28 43.61 45.75
November 2013 Final Report Appendix J Page J 5
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
7/19/2011 48 1.74 1.76 1.79 243 42.28 45.12 49.71
7/20/2011 48 1.69 1.74 1.78 228 42.76 46.54 51.59
7/21/2011 48 1.69 1.73 1.79 197 44.31 46.23 48.56
7/22/2011 48 1.67 1.70 1.73 273 44.47 47.27 51.53
7/23/2011 48 1.69 1.80 2.00 440 45.47 47.29 50.21
7/24/2011 48 1.84 1.91 2.00 472 43.52 44.75 46.01
7/25/2011 48 1.88 1.94 2.03 452 43.14 44.14 45.57
7/26/2011 48 1.85 1.92 1.98 414 41.90 44.07 45.60
7/27/2011 48 1.81 1.87 1.92 351 43.04 45.00 47.91
7/28/2011 48 1.78 1.83 1.89 286 43.93 45.27 47.20
7/29/2011 48 1.74 1.78 1.82 269 43.87 45.75 47.97
7/30/2011 48 1.73 1.77 1.81 242 44.84 45.55 46.35
7/31/2011 48 1.72 1.74 1.79 240 44.28 45.25 46.72
8/1/2011 48 1.71 1.74 1.77 378 44.53 45.64 46.76
8/2/2011 48 1.76 1.90 1.98 427 45.32 46.21 47.45
8/3/2011 48 1.83 1.88 1.95 398 45.00 46.25 47.73
8/4/2011 48 1.81 1.97 2.14 471 43.90 45.01 46.07
8/5/2011 48 1.88 1.96 2.04 450 41.87 43.12 44.56
8/6/2011 48 1.85 1.98 2.17 41.58 42.38 43.24 (1)
8/7/2011 48 1.94 2.04 2.13 464 41.52 43.03 44.97
8/8/2011 48 1.87 1.93 2.02 474 42.00 42.66 43.27
8/9/2011 48 1.90 2.01 2.15 450 41.78 43.09 45.23
8/10/2011 48 1.87 1.98 2.13 465 42.63 44.68 47.88
8/11/2011 48 1.88 1.94 2.00 457 42.54 45.27 48.78
8/12/2011 48 1.86 1.91 1.95 391 43.93 45.23 46.51
8/13/2011 48 1.78 1.86 1.95 327 44.68 46.50 49.09
8/14/2011 48 1.76 1.81 1.88 259 45.69 47.03 49.34
8/15/2011 48 1.72 1.76 1.80 215 42.69 46.13 50.23
8/16/2011 48 1.68 1.72 1.75 189 43.58 46.92 50.79
8/17/2011 48 1.64 1.69 1.73 180 45.44 47.29 49.37
8/18/2011 48 1.65 1.68 1.71 238 46.13 46.95 47.72
8/19/2011 48 1.68 1.74 1.83 259 45.78 46.35 46.79
8/20/2011 48 1.71 1.76 1.83 202 44.68 45.99 47.51
8/21/2011 48 1.67 1.70 1.76 191 44.53 46.08 48.07
8/22/2011 48 1.67 1.69 1.72 178 43.99 45.18 46.07
8/23/2011 48 1.65 1.67 1.70 163 43.39 44.58 47.22
8/24/2011 48 1.63 1.65 1.67 167 41.96 43.29 44.40
8/25/2011 48 1.64 1.66 1.68 152 43.48 45.01 47.07
8/26/2011 48 1.61 1.64 1.67 140 43.99 46.13 49.27
8/27/2011 48 1.59 1.62 1.64 128 43.45 45.23 46.47
8/28/2011 48 1.58 1.60 1.61 119 42.31 45.64 50.20
8/29/2011 48 1.56 1.58 1.60 117 43.20 45.85 48.93
8/30/2011 48 1.57 1.58 1.60 242 45.15 46.43 48.31
8/31/2011 48 1.58 1.74 1.84 189 45.19 45.97 47.35
9/1/2011 48 1.65 1.69 1.75 188 42.97 45.06 47.44
9/2/2011 48 1.65 1.69 1.72 181 44.18 45.03 46.10
9/3/2011 48 1.64 1.68 1.71 169 44.02 45.25 46.54
9/4/2011 48 1.64 1.66 1.69 154 43.93 45.24 47.22
9/5/2011 48 1.60 1.64 1.66 142 42.69 44.23 45.59
9/6/2011 48 1.60 1.62 1.65 154 43.42 44.77 46.16
9/7/2011 48 1.61 1.64 1.72 374 43.99 45.22 46.95
9/8/2011 48 1.72 1.86 1.97 256 44.12 45.14 46.66
9/9/2011 48 1.72 1.75 1.80 213 40.98 43.72 47.60
9/10/2011 48 1.68 1.71 1.75 191 42.98 44.52 46.98
9/11/2011 48 1.66 1.69 1.72 181 43.64 44.63 46.57
9/12/2011 48 1.65 1.68 1.70 178 43.77 44.77 46.19
November 2013 Final Report Appendix J Page J 6
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
9/13/2011 48 1.64 1.67 1.78 400 43.89 45.07 47.07
9/14/2011 48 1.80 1.87 1.96 388 43.62 44.51 46.01
9/15/2011 48 1.80 1.93 2.06 444 43.14 43.71 44.72
9/16/2011 48 1.84 1.91 1.99 385 42.16 43.53 45.28
9/17/2011 48 1.80 1.85 1.90 295 42.00 43.17 44.94
9/18/2011 48 1.73 1.79 1.83 250 41.13 42.82 45.16
9/19/2011 48 1.72 1.75 1.79 237 41.87 42.75 43.93
9/20/2011 48 1.69 1.74 1.78 287 42.00 43.28 45.19
9/21/2011 48 1.71 1.78 1.83 254 42.38 43.54 45.47
9/22/2011 48 1.74 1.76 1.81 228 41.93 43.32 45.09
9/23/2011 48 1.70 1.73 1.77 238 40.11 42.17 44.24
9/24/2011 48 1.68 1.74 1.81 241 41.00 41.87 43.14
9/25/2011 48 1.71 1.74 1.78 217 40.14 41.75 43.77
9/26/2011 48 1.69 1.72 1.75 199 38.92 40.71 44.43
9/27/2011 48 1.68 1.70 1.73 183 38.02 39.75 42.66
9/28/2011 48 1.65 1.68 1.72 165 37.63 39.32 41.03
9/29/2011 48 1.63 1.66 1.69 149 37.69 39.41 41.42
9/30/2011 48 1.62 1.63 1.66 141 36.56 38.56 40.91
10/1/2011 48 1.60 1.62 1.65 138 39.05 40.26 42.02
10/2/2011 48 1.59 1.62 1.64 160 39.31 40.42 41.80
10/3/2011 48 1.58 1.65 1.72 136 39.50 40.22 41.39
10/4/2011 48 1.59 1.61 1.63 153 37.30 39.29 41.86
10/5/2011 48 1.57 1.64 1.72 172 38.02 39.17 40.20
10/6/2011 48 1.63 1.66 1.74 164 38.02 39.60 41.42
10/7/2011 48 1.63 1.66 1.68 154 38.95 40.18 41.67
10/8/2011 48 1.62 1.64 1.66 139 38.27 39.45 41.16
10/9/2011 48 1.59 1.62 1.65 126 36.62 38.31 40.39
10/10/2011 48 1.57 1.59 1.62 114 35.65 37.34 39.47
10/11/2011 48 1.55 1.57 1.60 104 34.60 36.04 38.34
10/12/2011 48 1.53 1.55 1.58 107 33.19 34.92 36.66
10/13/2011 48 1.54 1.56 1.59 206 36.10 37.50 38.95
10/14/2011 48 1.59 1.70 1.85 210 38.14 38.80 39.63
10/15/2011 48 1.68 1.71 1.76 171 37.63 38.81 39.95
10/16/2011 48 1.64 1.66 1.70 147 35.48 36.37 37.85
10/17/2011 48 1.61 1.63 1.65 134 33.62 34.84 36.72
10/18/2011 48 1.59 1.61 1.63 122 33.52 34.71 36.56
10/19/2011 48 1.57 1.59 1.62 116 32.26 33.92 35.91
10/20/2011 48 1.56 1.58 1.59 112 33.97 35.54 37.56
10/21/2011 48 1.56 1.57 1.60 102 36.75 37.43 38.66
10/22/2011 48 1.53 1.55 1.57 101 35.25 36.25 37.79
10/23/2011 48 1.52 1.55 1.58 121 35.67 36.92 38.24
10/24/2011 48 1.54 1.59 1.64 356 35.74 37.13 38.27
10/25/2011 48 1.66 1.90 2.12 242 36.62 37.75 38.31
10/26/2011 48 1.70 1.74 1.82 187 34.11 34.94 36.40
10/27/2011 48 1.66 1.68 1.71 173 34.86 36.05 37.27
10/28/2011 48 1.65 1.67 1.69 150 36.10 36.88 38.27
10/29/2011 48 1.61 1.64 1.67 125 35.68 36.49 37.66
10/30/2011 48 1.57 1.59 1.63 118 32.03 33.31 35.81
10/31/2011 48 1.56 1.58 1.61 104 31.93 33.29 34.66
11/1/2011 48 1.51 1.55 1.58 110 31.30 32.68 33.91
11/2/2011 48 1.51 1.71 1.86 118 31.34 31.38 31.44
11/3/2011 48 1.50 1.56 1.81 97 31.37 32.06 33.12
11/4/2011 48 1.50 1.53 1.56 90 31.83 33.16 34.04
11/5/2011 48 1.49 1.52 1.59 80 31.34 31.78 32.72
11/6/2011 48 1.47 1.49 1.51 75 31.37 31.74 32.49
11/7/2011 48 1.47 1.82 2.25 70 31.34 31.39 31.45
November 2013 Final Report Appendix J Page J 7
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
11/8/2011 48 2.25 2.42 2.58 65 31.32 31.38 31.46
11/9/2011 48 1.53 2.50 2.91 63 31.33 31.39 31.54
11/10/2011 48 1.42 1.43 1.52 57 31.60 32.50 33.19
11/11/2011 48 1.40 1.41 1.43 53 31.36 32.32 32.95
11/12/2011 48 1.38 1.40 1.42 55 31.40 32.19 32.59
11/13/2011 48 1.39 1.41 1.43 52 31.30 31.45 31.99
11/14/2011 48 1.38 1.39 1.43 48 31.33 31.71 32.16
11/15/2011 48 1.33 1.62 1.86 34 31.30 31.36 31.43
11/16/2011 48 1.09 1.15 1.29 34 31.29 31.36 31.39
11/17/2011 48 1.08 1.27 1.43 34 31.33 31.37 31.47
11/18/2011 48 1.34 1.63 1.88 34 31.31 31.37 31.41
11/19/2011 48 1.52 1.71 1.83 34 31.34 31.38 31.44
11/20/2011 48 1.35 1.39 1.51 34 31.36 31.41 31.47
11/21/2011 48 1.25 1.31 1.36 34 31.33 31.40 31.43
11/22/2011 48 1.24 1.30 1.35 38 31.33 31.39 31.43
11/23/2011 48 1.30 1.32 1.34 36 31.36 31.42 31.46
11/24/2011 48 1.29 1.31 1.33 34 31.40 31.43 31.46
11/25/2011 48 1.28 1.29 1.31 31 31.40 31.44 31.49
11/26/2011 48 1.26 1.28 1.29 32 31.40 31.43 31.49
11/27/2011 48 1.26 1.28 1.30 32 31.40 31.43 31.49
11/28/2011 48 1.27 1.29 1.30 32 31.49 31.64 31.79
11/29/2011 48 1.28 1.28 1.30 32 31.83 32.22 32.65
11/30/2011 48 1.27 1.28 1.29 31 32.59 33.02 33.24
12/1/2011 48 1.26 1.28 1.29 31 32.36 32.68 33.08
12/2/2011 48 1.26 1.27 1.31 31 33.05 33.22 33.35
12/3/2011 48 1.27 1.33 1.41 31 32.03 32.78 33.48
12/4/2011 48 1.36 1.42 1.49 31 31.53 32.21 32.75
12/5/2011 48 1.32 1.33 1.36 31 31.93 32.21 32.59
12/6/2011 48 1.30 1.31 1.32 31 31.63 32.16 32.69
12/7/2011 48 1.29 1.30 1.32 31 32.09 32.55 33.21
12/8/2011 48 1.29 1.30 1.32 31 33.15 33.47 33.74
12/9/2011 48 1.27 1.29 1.30 31 32.09 32.88 33.11
12/10/2011 48 1.26 1.28 1.29 34 31.43 31.85 32.26
12/11/2011 48 1.27 1.30 1.32 33 31.96 32.39 32.85
12/12/2011 48 1.27 1.29 1.31 54 31.33 31.97 32.29
12/13/2011 48 1.10 1.36 1.58 62 31.33 31.37 31.43
12/14/2011 48 1.26 1.37 1.74 30 31.33 31.62 32.32
12/15/2011 48 1.26 1.27 1.28 30 32.32 32.76 33.15
12/16/2011 48 1.26 1.27 1.28 30 33.02 33.15 33.28
12/17/2011 48 1.26 1.27 1.28 55 33.11 33.34 33.51
12/18/2011 48 1.28 1.40 1.47 43 31.63 32.39 33.44
12/19/2011 48 1.32 1.35 1.37 37 32.19 32.58 32.92
12/20/2011 48 1.30 1.32 1.33 34 31.89 32.49 33.02
12/21/2011 48 1.29 1.30 1.31 34 31.66 32.36 32.78
12/22/2011 48 1.28 1.66 1.84 34 31.31 31.36 31.56
12/23/2011 48 1.34 1.47 1.70 34 31.33 31.36 31.40
12/24/2011 48 1.20 1.56 1.87 34 31.30 31.36 31.43
12/25/2011 48 1.12 1.16 1.21 36 31.29 31.36 31.40
12/26/2011 48 1.22 1.31 1.35 43 31.30 31.36 31.43
12/27/2011 48 1.31 1.35 1.38 46 31.33 31.35 31.43
12/28/2011 48 1.34 1.37 1.39 41 31.30 31.34 31.40
12/29/2011 48 1.29 1.33 1.41 33 31.30 31.36 31.43
12/30/2011 48 1.28 1.29 1.31 32 31.33 31.39 31.43
12/31/2011 48 1.27 1.28 1.29 35 31.36 31.40 31.46
1/1/2012 48 1.28 1.30 1.32 33 31.36 31.41 31.49
1/2/2012 48 1.32 1.35 1.38 40 31.36 31.42 31.46
November 2013 Final Report Appendix J Page J 8
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
1/3/2012 48 1.38 1.40 1.41 39 31.40 31.43 31.49
1/4/2012 48 1.38 1.39 1.41 39 31.40 31.46 31.49
1/5/2012 48 1.37 1.39 1.41 37 31.43 31.48 31.53
1/6/2012 48 1.37 1.38 1.39 36 31.49 31.52 31.56
1/7/2012 48 1.37 1.38 1.39 35 31.53 31.64 31.76
1/8/2012 48 1.34 1.37 1.39 34 31.60 31.74 31.86
1/9/2012 48 1.35 1.36 1.37 41 31.60 31.70 31.79
1/10/2012 48 1.36 1.40 1.55 33 31.56 31.66 31.76
1/11/2012 48 1.34 1.35 1.38 29 31.69 31.79 31.86
1/12/2012 48 1.30 1.33 1.34 30 31.43 31.56 31.83
1/13/2012 48 1.32 1.34 1.35 29 31.46 31.54 31.66
1/14/2012 48 1.32 1.32 1.34 28 31.53 31.58 31.63
1/15/2012 48 1.31 1.32 1.33 28 31.56 31.61 31.69
1/16/2012 48 1.30 1.31 1.33 27 31.56 31.62 31.66
1/17/2012 48 1.30 1.31 1.32 26 31.60 31.63 31.69
1/18/2012 48 1.29 1.30 1.31 26 31.60 31.68 31.73
1/19/2012 48 1.29 1.30 1.31 25 31.60 31.65 31.73
1/20/2012 48 1.29 1.30 1.30 25 31.60 31.66 31.73
1/21/2012 48 1.28 1.29 1.30 24 31.53 31.57 31.66
1/22/2012 48 1.27 1.28 1.30 24 31.53 31.60 31.73
1/23/2012 48 1.27 1.28 1.29 23 31.73 31.87 31.99
1/24/2012 48 1.26 1.27 1.28 22 31.86 31.93 31.99
1/25/2012 48 1.25 1.26 1.27 21 31.76 31.81 31.89
1/26/2012 48 1.25 1.26 1.27 21 31.66 31.72 31.79
1/27/2012 48 1.24 1.25 1.26 21 31.53 31.59 31.66
1/28/2012 48 1.24 1.25 1.26 20 31.49 31.55 31.63
1/29/2012 48 1.24 1.25 1.25 20 31.56 31.73 31.93
1/30/2012 48 1.23 1.24 1.25 18 31.93 32.10 32.29
1/31/2012 48 1.19 1.21 1.24 22 32.22 32.37 32.52
2/1/2012 48 1.18 1.20 1.21 22 32.06 32.30 32.55
2/2/2012 48 1.17 1.19 1.21 21 31.63 31.96 32.39
2/3/2012 48 1.17 1.18 1.19 20 31.52 31.70 31.79
2/4/2012 48 1.13 1.18 1.22 22 31.52 31.58 31.66
2/5/2012 48 1.18 1.20 1.24 25 31.59 31.79 31.96
2/6/2012 48 1.21 1.22 1.24 21 31.66 31.96 32.19
2/7/2012 48 1.17 1.19 1.21 20 32.22 32.45 32.62
2/8/2012 48 1.16 1.18 1.23 26 32.06 32.62 32.92
2/9/2012 48 1.19 1.24 1.26 20 31.63 32.00 32.36
2/10/2012 48 1.15 1.17 1.20 18 32.32 32.66 33.11
2/11/2012 48 1.14 1.15 1.16 16 32.52 32.73 32.84
2/12/2012 48 1.12 1.13 1.15 16 32.25 32.48 32.71
2/13/2012 48 1.11 1.12 1.13 15 31.79 32.11 32.42
2/14/2012 48 1.10 1.11 1.12 14 31.72 31.95 32.28
2/15/2012 48 1.06 1.10 1.14 16 31.56 31.72 31.92
2/16/2012 48 1.11 1.12 1.13 15 31.79 32.14 32.45
2/17/2012 48 1.10 1.11 1.11 14 32.15 32.43 32.75
2/18/2012 48 1.09 1.10 1.11 14 32.28 32.50 32.71
2/19/2012 48 1.09 1.10 1.11 14 32.48 32.71 32.98
2/20/2012 48 1.09 1.10 1.11 14 32.28 32.61 32.84
2/21/2012 48 1.09 1.09 1.10 14 31.89 32.18 32.58
2/22/2012 48 1.08 1.09 1.10 13 31.79 32.10 32.25
2/23/2012 48 1.08 1.08 1.09 13 31.46 31.68 31.85
2/24/2012 48 1.06 1.08 1.13 14 31.33 31.41 31.49
2/25/2012 48 1.07 1.10 1.12 14 31.36 31.59 31.79
2/26/2012 48 1.05 1.09 1.11 13 31.52 31.84 32.05
2/27/2012 48 1.04 1.08 1.09 14 31.43 32.05 32.32
November 2013 Final Report Appendix J Page J 9
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
2/28/2012 48 1.01 1.09 1.16 20 31.36 31.40 31.43
2/29/2012 48 1.11 1.18 1.22 20 31.36 31.42 31.49
3/1/2012 48 1.11 1.17 1.22 13 31.39 31.55 31.66
3/2/2012 48 1.07 1.09 1.10 13 31.62 31.73 31.82
3/3/2012 48 1.06 1.07 1.08 12 31.49 31.66 31.75
3/4/2012 48 1.06 1.07 1.08 13 31.43 31.49 31.56
3/5/2012 48 1.06 1.07 1.08 12 31.43 31.57 31.69
3/6/2012 48 1.06 1.06 1.07 12 31.66 31.95 32.19
3/7/2012 48 1.05 1.06 1.07 12 32.09 32.29 32.61
3/8/2012 48 1.05 1.06 1.07 12 32.02 32.21 32.35
3/9/2012 48 1.04 1.06 1.06 12 31.46 31.65 32.02
3/10/2012 48 1.04 1.05 1.06 12 31.39 31.52 31.72
3/11/2012 48 1.05 1.06 1.07 13 31.39 31.49 31.62
3/12/2012 48 1.05 1.07 1.08 12 31.43 31.49 31.59
3/13/2012 48 1.05 1.07 1.09 11 31.43 31.53 31.62
3/14/2012 48 1.04 1.05 1.06 11 31.49 31.60 31.69
3/15/2012 48 1.04 1.04 1.05 11 31.49 31.63 31.72
3/16/2012 48 1.03 1.04 1.04 11 31.59 31.69 31.85
3/17/2012 48 1.02 1.03 1.05 11 31.43 31.52 31.66
3/18/2012 48 1.02 1.04 1.07 12 31.43 31.49 31.59
3/19/2012 48 1.05 1.06 1.07 12 31.43 31.51 31.62
3/20/2012 48 1.05 1.06 1.08 12 31.43 31.50 31.59
3/21/2012 48 1.05 1.06 1.07 12 31.39 31.50 31.59
3/22/2012 48 1.04 1.05 1.06 12 31.46 31.52 31.62
3/23/2012 48 1.02 1.06 1.10 12 31.43 31.49 31.56
3/24/2012 48 1.03 1.06 1.10 10 31.46 31.54 31.66
3/25/2012 48 1.02 1.03 1.04 10 31.49 31.62 31.82
3/26/2012 48 1.02 1.02 1.03 10 31.59 31.84 32.05
3/27/2012 48 1.02 1.03 1.05 12 31.99 32.15 32.35
3/28/2012 48 1.04 1.06 1.08 12 32.05 32.38 32.78
3/29/2012 48 1.05 1.06 1.08 11 32.52 33.00 33.70
3/30/2012 48 1.04 1.05 1.07 11 32.32 33.05 33.90
3/31/2012 48 1.03 1.03 1.05 10 32.58 33.23 33.90
4/1/2012 48 1.02 1.03 1.03 10 32.91 33.38 33.80
4/2/2012 48 1.02 1.03 1.03 10 32.91 33.45 34.29
4/3/2012 48 1.02 1.02 1.03 10 32.09 32.73 33.27
4/4/2012 48 1.01 1.02 1.03 15 32.25 32.80 33.24
4/5/2012 48 1.02 1.11 1.16 12 31.82 32.26 33.17
4/6/2012 48 1.05 1.07 1.10 11 31.89 32.61 33.44
4/7/2012 48 1.04 1.05 1.05 11 32.35 33.18 34.10
4/8/2012 48 1.03 1.04 1.06 11 32.55 33.06 33.70
4/9/2012 48 1.03 1.04 1.05 11 32.68 33.45 34.32
4/10/2012 48 1.03 1.04 1.05 11 33.01 33.77 34.68
4/11/2012 48 1.03 1.04 1.05 11 32.35 33.57 34.88
4/12/2012 48 1.03 1.04 1.05 11 32.88 33.84 34.91
4/13/2012 48 1.03 1.05 1.06 13 32.81 33.93 35.21
4/14/2012 48 1.05 1.07 1.10 19 33.44 34.09 34.85
4/15/2012 48 1.10 1.17 1.24 26 33.21 33.74 34.46
4/16/2012 48 1.21 1.24 1.26 29 32.95 34.06 35.73
4/17/2012 48 1.23 1.26 1.28 33 33.31 34.31 35.90
4/18/2012 48 1.27 1.29 1.31 34 33.18 34.29 36.03
4/19/2012 46 1.28 1.29 1.31 35 32.75 34.53 36.81
4/20/2012 48 1.29 1.30 1.33 36 32.85 34.47 36.74
4/21/2012 48 1.29 1.31 1.33 33 33.15 33.89 34.75
4/22/2012 48 1.26 1.29 1.34 41 33.31 35.27 38.40
4/23/2012 48 1.32 1.34 1.37 42 33.54 34.91 37.30
November 2013 Final Report Appendix J Page J 10
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
4/24/2012 48 1.33 1.35 1.37 47 32.69 34.89 38.40
4/25/2012 48 1.35 1.37 1.40 55 32.72 34.99 38.56
4/26/2012 48 1.38 1.41 1.45 66 32.92 35.08 38.78
4/27/2012 48 1.42 1.45 1.48 73 33.19 35.14 38.69
4/28/2012 48 1.44 1.47 1.51 78 33.94 35.41 37.72
4/29/2012 48 1.47 1.49 1.52 83 33.84 35.57 38.11
4/30/2012 48 1.48 1.50 1.53 79 33.65 35.41 38.33
5/1/2012 48 1.46 1.49 1.51 68 32.79 34.59 38.14
5/2/2012 48 1.44 1.45 1.47 63 32.03 34.76 38.75
5/3/2012 48 1.43 1.44 1.45 60 33.48 35.78 38.62
5/4/2012 48 1.41 1.42 1.44 60 34.37 36.14 39.43
5/5/2012 48 1.41 1.43 1.45 64 34.37 36.36 39.72
5/6/2012 48 1.42 1.44 1.46 74 34.53 36.55 39.62
5/7/2012 48 1.45 1.48 1.53 82 34.73 36.80 40.71
5/8/2012 48 1.47 1.50 1.53 73 34.27 35.48 37.53
5/9/2012 48 1.45 1.47 1.49 76 33.74 35.46 37.46
5/10/2012 48 1.46 1.48 1.50 75 33.94 36.19 39.88
5/11/2012 48 1.46 1.48 1.49 70 33.81 35.73 38.69
5/12/2012 48 1.45 1.46 1.48 68 34.20 36.35 39.72
5/13/2012 48 1.44 1.45 1.47 67 33.71 36.39 40.04
5/14/2012 48 1.44 1.45 1.46 71 33.48 36.31 39.72
5/15/2012 48 1.44 1.47 1.52 89 33.81 37.51 42.91
5/16/2012 48 1.48 1.52 1.60 130 33.65 37.42 42.94
5/17/2012 48 1.56 1.61 1.68 167 34.79 37.45 42.24
5/18/2012 48 1.63 1.66 1.69 159 33.91 36.39 40.78
5/19/2012 48 1.62 1.65 1.67 158 34.86 36.68 39.27
5/20/2012 48 1.62 1.65 1.68 183 34.90 36.90 39.24
5/21/2012 48 1.65 1.68 1.75 234 34.83 37.42 41.35
5/22/2012 48 1.68 1.74 1.84 329 34.73 37.08 40.59
5/23/2012 48 1.74 1.83 1.93 394 34.83 36.91 41.26
5/24/2012 48 1.80 1.85 1.93 440 34.35 36.16 39.63
5/25/2012 48 1.84 1.89 1.96 385 35.03 36.04 37.86
5/26/2012 48 1.80 1.85 1.92 364 34.61 35.74 36.85
5/27/2012 48 1.80 1.84 1.93 442 35.16 36.88 40.34
5/28/2012 48 1.83 1.89 1.93 425 35.16 36.10 37.70
5/29/2012 48 1.83 1.88 1.93 426 34.77 36.60 39.31
5/30/2012 48 1.83 1.88 1.93 396 34.87 36.59 38.67
5/31/2012 48 1.81 1.86 1.91 413 34.77 36.97 39.95
6/1/2012 48 1.81 1.87 1.95 457 34.38 37.39 41.71
6/2/2012 48 1.86 1.91 1.96 499 35.20 36.84 40.30
6/3/2012 48 1.91 1.99 2.08 464 34.70 36.45 40.02
6/4/2012 48 1.89 2.00 2.08 475 34.48 35.84 37.31
6/5/2012 48 1.88 1.95 2.06 474 33.98 37.10 41.40
6/6/2012 48 1.88 1.94 2.02 34.64 37.23 41.46 (1)
6/7/2012 48 1.98 2.05 2.20 35.52 37.22 39.99 (1)
6/8/2012 48 1.95 2.05 2.17 455 34.61 35.76 36.92
6/9/2012 48 1.89 1.97 2.06 495 35.36 36.95 40.05
6/10/2012 48 1.91 1.97 2.08 482 34.80 36.90 39.60
6/11/2012 48 1.88 1.94 1.98 35.59 36.93 38.54 (1)
6/12/2012 48 1.91 1.98 2.05 486 35.52 36.22 36.92
6/13/2012 48 1.90 1.98 2.08 35.49 36.33 37.25 (1)
6/14/2012 48 2.02 2.12 2.35 35.39 37.29 40.88 (1)
6/15/2012 48 2.04 2.13 2.50 34.58 37.19 41.07 (1)
6/16/2012 48 1.97 2.07 2.18 34.87 38.15 42.63 (1)
6/17/2012 48 2.02 2.14 2.53 35.49 37.93 42.86 (1)
6/18/2012 48 1.92 2.17 2.52 451 35.56 36.45 37.41
November 2013 Final Report Appendix J Page J 11
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
6/19/2012 48 1.89 2.03 2.15 416 35.82 37.06 38.54
6/20/2012 48 1.86 2.06 2.17 36.18 38.02 41.14 (1)
6/21/2012 48 1.97 2.17 2.78 35.75 38.68 42.95 (1)
6/22/2012 48 2.05 2.31 3.15 451 36.18 38.77 43.12
6/23/2012 48 1.89 2.35 2.96 200 35.96 38.54 42.23
6/24/2012 48 1.18 2.22 2.80 329 36.24 37.17 37.86
6/25/2012 48 1.81 2.10 2.49 474 36.18 37.10 38.38
6/26/2012 48 1.90 2.02 2.14 460 36.63 37.29 38.51
6/27/2012 48 1.87 1.93 2.01 459 36.63 38.34 40.43
6/28/2012 48 1.85 1.92 2.01 466 37.18 38.06 39.47
6/29/2012 48 1.85 1.93 1.99 479 37.08 38.72 41.96
6/30/2012 48 1.89 1.96 2.06 462 37.02 39.78 44.00
7/1/2012 48 1.88 1.94 2.03 451 37.66 39.15 40.98
7/2/2012 48 1.84 1.90 1.97 402 37.76 38.47 39.47
7/3/2012 48 1.79 1.86 1.92 460 37.34 38.23 39.31
7/4/2012 48 1.84 1.94 2.11 475 37.21 38.55 40.21
7/5/2012 48 1.88 1.98 2.11 462 36.92 38.86 41.49
7/6/2012 48 1.87 1.92 1.99 451 37.41 39.37 41.39
7/7/2012 48 1.84 1.90 1.95 499 37.63 40.10 43.33
7/8/2012 48 1.91 1.98 2.04 463 37.99 38.71 40.30
7/9/2012 48 1.85 1.91 1.97 428 37.50 39.50 42.67
7/10/2012 48 1.83 1.88 1.96 443 36.73 39.49 42.06
7/11/2012 48 1.86 1.99 2.13 431 38.76 39.33 40.28
7/12/2012 48 1.86 2.00 2.15 426 38.15 39.18 40.66
7/13/2012 48 1.81 1.90 1.99 450 37.76 39.69 41.42
7/14/2012 48 1.84 1.93 2.03 433 39.37 40.17 41.84
7/15/2012 48 1.88 1.96 2.03 451 38.54 39.26 40.21
7/16/2012 48 1.84 1.90 1.98 415 38.47 39.53 40.94
7/17/2012 48 1.80 1.87 1.93 399 37.66 41.45 47.07
7/18/2012 48 1.80 1.87 1.94 425 39.18 42.88 47.91
7/19/2012 48 1.80 1.89 1.97 444 40.46 41.71 43.68
7/20/2012 48 1.84 1.95 2.13 496 39.89 42.33 46.29
7/21/2012 48 1.91 2.09 2.21 41.01 41.52 42.29 (1)
7/22/2012 48 1.95 2.06 2.14 498 39.67 40.78 41.94
7/23/2012 48 1.91 1.99 2.06 457 40.40 41.03 41.74
7/24/2012 48 1.86 1.93 2.02 418 39.89 41.87 45.13
7/25/2012 48 1.81 1.89 2.03 498 39.63 43.38 48.51
7/26/2012 48 1.91 1.96 2.03 420 42.06 44.26 47.73
7/27/2012 48 1.82 1.88 2.00 419 41.49 42.75 44.06
7/28/2012 48 1.81 1.89 1.95 429 41.36 44.17 48.38
7/29/2012 48 1.87 2.06 2.34 272 42.03 42.96 44.60
7/30/2012 48 1.66 2.18 2.43 40.08 41.61 43.72 (1)
7/31/2012 48 1.95 2.02 2.17 39.64 41.79 43.81 (1)
8/1/2012 48 2.05 2.15 2.22 41.37 42.15 42.92 (1)
8/2/2012 48 2.03 2.27 2.83 40.02 40.61 41.88 (1)
8/3/2012 48 1.96 2.13 2.42 39.99 41.00 42.45 (1)
8/4/2012 48 1.99 2.04 2.11 40.24 40.83 41.43 (1)
8/5/2012 48 1.93 1.98 2.06 467 39.99 42.09 45.19
8/6/2012 48 1.87 1.93 2.00 418 39.98 43.27 47.85
8/7/2012 48 1.84 1.87 1.95 339 42.28 43.68 45.32
8/8/2012 48 1.77 1.82 1.86 297 41.65 44.39 48.47
8/9/2012 48 1.75 1.79 1.84 296 42.31 45.11 48.90
8/10/2012 48 1.75 1.79 1.83 259 44.08 45.26 46.95
8/11/2012 48 1.71 1.76 1.81 236 43.14 46.02 50.45
8/12/2012 48 1.70 1.74 1.78 222 43.01 46.48 51.13
8/13/2012 48 1.67 1.72 1.77 232 44.24 47.32 51.47
November 2013 Final Report Appendix J Page J 12
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study
Polarconsult Alaska, Inc.
Recorded Stage (ft, station datum) Water Temperature (F)
DATE Record
Count
Daily
Minimum Daily Mean Daily
Maximum
Calculated Mean
Daily Flow
Daily
Minimum
Daily
Mean
Daily
Maximum Notes
8/14/2012 48 1.70 1.73 1.78 218 45.47 47.41 49.96
8/15/2012 48 1.69 1.72 1.76 203 45.41 46.89 49.53
8/16/2012 48 1.67 1.70 1.77 174 44.50 45.53 46.72
8/17/2012 48 1.62 1.67 1.72 195 43.39 45.22 47.51
8/18/2012 48 1.60 1.69 1.88 269 42.59 44.15 45.16
8/19/2012 48 1.71 1.76 1.88 231 43.58 44.30 45.35
8/20/2012 48 1.67 1.73 1.79 173 42.63 44.25 46.07
8/21/2012 48 1.63 1.66 1.71 149 41.23 43.61 45.60
8/22/2012 48 1.59 1.63 1.66 218 41.29 43.64 45.66
8/23/2012 48 1.64 1.72 1.77 210 43.17 44.31 46.19
8/24/2012 48 1.65 1.71 1.76 241 42.50 43.34 44.65
8/25/2012 17 1.72 1.74 1.76 238 42.98 43.31 43.71 (3)
Notes:
2. Gauge hardware installed.
3. Most recent station data download.
1. Stage value is outside the calibrated range of the stage-discharge curve for the station, so a calculated flow value is not
reported. Flow is estimated to exceed 500 cfs.
November 2013 Final Report Appendix J Page J 13
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report
APPENDIX K CONCEPTUAL DESIGN DRAWINGS
Pedro Bay Village Council
Knutson Creek Hydroelectric Feasibility Study Polarconsult Alaska, Inc.
November 2013 Final Report K 1
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*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
***11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***
*** 11/9/2012 CONCEPTUAL DRAWINGS ***FOR PERMITTING AND PLANNING PURPOSES ONLY*** NOT FOR CONSTRUCTION ***