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Grant Lake Proposed Hydroelectric Project Reconnaissance Report Prepared for: Kenai Hydro, LLC HDR Alaska, Inc. 2525 C Street, Suite 305 Anchorage, AK 99503 March 2009

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  • Grant Lake Proposed Hydroelectric Project

    Reconnaissance Report

    Prepared for:

    Kenai Hydro, LLC

    HDR Alaska, Inc. 2525 C Street, Suite 305

    Anchorage, AK 99503

    March 2009

  • Grant Lake and Falls Creek Hv,rir(],p/p'ririr

    Reconnaissance Report Update

    The Grant Lake Falls Creek Hydroelectric project was first reviewed in the 1980's as a potential source of hydroelectric power. More recently, in 2008, a reconnaissance study aimed at identifying new alternatives for hydropower at Grant Lake was completed by Kenai Hydro LLC with a grant from the Alaska Energy Authority. Kenai Hydro LLC is a renewable energy partnership between Homer Electric Association and Wind Energy Alaska.

    This update is intended to document changes to the project layout and features associated with the Grant LakelFalls Creek hydroelectric project development since the completion of the Reconnaissance Report in March 2009. These changes in the project are as a result of many different factors including;

    More accurate environmental data gathered through one full field season of project impact studies;

    Several reconnaissance field trips to walk potential pipeline and road alignments; A ground survey of the lake outlet and the potential power house location; Acquisition of Lidar geographic data provided by the Kenai Watershed Forum; Additional feedback from agency representatives on information gathered in the field; Consultation with Homer Electric operations personnel on how this project would be integrated

    into the existing system.

    This new information has necessitated the modification of many aspects of the preferred layout identified in the March reconnaissance report. These changes are significant and will affect the construction, environmental impact, operation, and cost of the proposed facility.

    The changes are summarized below.

    1. Replacement of penstock with tunnel. This major change was a result of several field visits to the site to stake out a potential penstock alignment as shown in several of the early studies of the project. The site walks and new Lidar data made available showed that there was not a cost effective means of conveying the water from the intake to the powerhouse with a penstock. A route along the edge of the canyon proved to be too steep and unstable to allow excavating a bench for the pipe. An overland route along the north side of Grant Creek had an unfavorable profile which would preclude gravity flow. Low saddles along the lake were also reviewed using the Lidar data and none proved low enough for a penstock alignment.

    After determining that an above ground penstock would not be feasible, focus shifted to a tunnel to bring the water from a low level in the lake directly to the powerhouse. Preliminary work now calls for a 2800-lf 10ft diameter tunnel on the south side of the creek exiting the hillside directly above the powerhouse where the water conveyance system transitions to an above ground penstock for the remaining distance to the powerhouse.

    2. Intake configuration modifications. The switch to a tunnel and penstock necessitated several changes to the layout of the intake. Initially it was thought that a low head diversion structure with an intake and low level outlet integral to this structure was the preferred configuration. With a tunnel being used for conveyance, the intake structure was moved to the south east of the natural outlet and impoundment, into deeper water. It is currently configured as a tower type intake structure, with multiple level intakes to provide for temperature regulation in response to environmental concerns. The tunnel configuration now allows for a direct intake thus improving the reliability and operation of the system. A diversion with a crest elevation of706.0 is still required at the outlet of Grant Lake.

    The requirement of a low level outlet to release bypass flows into the canyon has not yet been determined. Such a requirement becomes very problematic at levels below the natural lake level,

    Technical Memo #1 October 2009

  • Grant Lake and Falls Creek Hvdrr,.el12'ctrlc

    as the topography below the natural outlet does not allow for an easy way to get water into the creek without significant excavation or pumping requirements.

    3. Unit size and configuration. After energy optimization studies and discussions with Homer Electric operations staff and fisheries biologists, the preliminary arrangement of the turbines and how they will be operated was decided. It was initially hoped that the project could be used to balance wind power production that Homer Electric has plans on developing. This type of operation would result in potentially large fluctuations in downstream flow levels in Grant Creek as load is either added or taken away from the turbines.

    Discussions with fish biologists have indicated that this type of operation could be harmful to resident fish. Furthermore, it is unlikely that the generating units would have enough capacity and response times to counter fluctuations in wind generation. With this information, it was decided that the plant would be designed to provide firm capacity in the winter and optimized energy production year round.

    The preferred selection has the plant equipped with two units. One smaller unit will be optimized for winter flows and an additional larger flow unit will be available for higher spring/summer flows. These units are 1.2MW and 3.3 MW Francis units. This unit selection is based upon preliminary studies and may be revised as additional operational constraints become known.

    4. Surge tank requirement. With the length of the water conveyance system and the use of reaction turbines, it is expected that some form of surge protection will be required to absorb water hammer effects and transients as load on the turbine changes. The current configuration uses an above ground surge tank located at the transition from tunnel to the penstock above the powerhouse. The final configuration will be determined once equipment selection and operational considerations are finalized. Other configurations that may be considered in final design to address surge include synchronous bypass valves in the powerhouse, a surge shaft in the tunnel, an inclined surge tank, and a partially buried surge tank excavated back into the hillside.

    5. Falls Creek intake location. The location described and depicted in the 1980's era studies for the Falls Creek Diversion was not in a suitable location. Site visits and Lidar data indicate that the diversion/intake should be located at approximately elevation 800. The exact location will be detailed upon further survey.

    These are the changes that have been made to the project since the original March 2009 HDR Reconnaissance report. These changes are the basis of the project description that was included in the Preliminary Application Document that was submitted to the FERC this fall. The project layout is still preliminary in nature, and will likely undergo changes in order to accommodate agency requirements. Items which still need further research include the intake configuration, surge tank configuration and location, and the exact location of the Falls Creek intake and pipeline. Work will be done to continue to refine the project as the FERC process evolves.

    An inclusion of modifications to the reconnaissance level cost estimate to reflect the above changes in project configuration is attached. Contingency levels and interest rates have been changed based upon KHL input. The revised estimate is included in the following pages.

    Technical Memo #1 October 2009

  • Grant Lake and Falls Creek H",frf)L'/ort .. if'

    GRANT LAKE

    OPINION OF PROBABLE COST

    Alternative 5 - Enhanced Storage + Falls Creek

    litem Amount

    330 LAND AND LAND RIGHTS

    .1 Land Rights Generation Plant LS $50,000 $50,000 0.3 $15,000

    .2 Special use permits LS $50,000 $50,000 0.3 $15,000

    .3 Surveying LS $100,000 $100,000 0.3 $30,000

    331 STRUCTURES AND IMPROVEMENTS .1 POWERHOUSE

    .1 Excavation 700 CY $150 $105,000 0.2 $21,000

    .2 Concrete (inc!. reinforcement) 390 CY $1,200 $468,000 0.2 $93,600

    .3 Metal Building 2700 SF $350 $945,000 0.2 $189,000

    .4 Misc. Metals 1 LS $50.000 $50.000 0.3 $15,000

    .5 HVAC. Plumbing & Electrical LS $50.000 $50.000 0.3 $15,000

    .6 Grounding Grid LS $25,000 $25.000 0.3 $7,500

    .7 Fire Protection LS $25,000 $25,000 0.3 $7,500

    332 RESERVOIRS, DAMS AND WATERWAYS

    .1 SITE WORK

    .1 Clearing/Drainage/Erosion Control LS $50,000 $50.000 0.3 $15.000

    .2 DAM AND SPILLWAY .1 Excavation 330 CY $150 $49.500 0.3 $14.850

    .2 Care of Water/Diversion 1 LS $250.000 $250.000 0.3 $75.000

    .3 Concrete (structural) 0 CY $1,200 $- 0.3 $-

    .4 Concrete (mass) 250 CY $1,000 $250.000 0.3 $75,000

    .3 INTAKE $-

    .1 Excavation 375 CY $150 $56,250 0.3 $16.875

    .2 Care of Water/Diversion 1 LS $100.000 $100,000 0.3 $30,000

    .3 Trash racks LS $50,000 $50.000 0.3 $15,000

    .4 Control Gate w/operator 2 LS $100,000 $200.000 0.3 $60.000

    .5 Shutoff Gate w/operator LS $150,000 $150,000 0.3 $45.000

    .6 Concrete (structural) 225 CY $1,500 $337,500 0.3 $101,250

    .7 Concrete (mass) 0 CY $1.000 $- 0.3 $-

    .8 Misc. Metals LS $25,000 $25,000 0.3 $7,500

    .9 Misc. electrical & mechanical LS $100,000 $100,000 0.3 $30,000 0.10 Access Bridge LS $200,000 $200,000 0.3 $60,000

    .4 LOW LEVEL OUTLET

    .1 Excavation 300 CY $150 $45,000 0.3 $13,500

    .2 Concrete (structural) 90 CY $1,200 $108,000 0.3 $32,400

    .3 Valve w/operator LS $100,000 $100,000 0.3 $30,000

    .4 Misc. Metals LS $50.000 $50.000 0.3 $15.000

    Technical Memo #1 October 2009

  • Grant Lake and Falls Creek H1Jl1rfl,>/pr'tr7t'

    .5 WATER CONDUCTORS AND ACCESSORIES

    .1 PENSTOCK ,a Clearing 0.7 ACRE $25,000 $18,652 0.3 $5,596

    .b Steel penstock material 650 LF $370 $240,500 0.2 $48,100

    .c Concrete (thrust blocks and supports) 150 CY $1,200 $180,000 0.3 $54,000

    .d Penstock installation 650 LF $250 $162,500 0.2 $32,500

    .e Slope stabilization 0.1 MI $250,000 $30,000 0.3 $9,000

    .f Surge tank LS $250,000 $250,000 0.3 $75,000

    .2 TUNNEL

    .a Excavation 2800 LF $1,500 $4,200,000 0.3 $1,260,000

    .b Tunnel Support 1400 LF $1,000 $1,400,000 0.3 $420,000

    .c Lining 1400 LF $500 $700,000 0.3 $210,000

    .d Portals 2 EA $250,000 $500,000 0.3 $150,000

    .3 TAILRACE

    .a Excavation LS $75,000 $75,000 0.3 $22,500

    .b Support and lining LS $25,000 $25,000 0.3 $7,500

    .4 FALLS CREEK PIPELINE

    .a Clearing 20.0 ACRE $25,000 $500,000 0.3 $150,000

    .b Steel pipeline material 13000 LF $130 $1,690,000 0.2 $338,000

    .c Concrete (thrust blocks and supports) 620 CY $1,200 $744,000 0.3 $223,200

    .d Pipeline installation 13000 LF $100 $1,300,000 0.2 $260,000

    .e Slope stabilization 2.5 MI $250,000 $625,000 0.3 $187,500

    .6 FALLS CREEK DIVERSION

    .1 Excavation 200 CY $150 $30,000 0.3 $9,000

    .2 Care of Water/Diversion 1 LS $150,000 $150,000 0.3 $45,000

    .3 Concrete (structural) 50 CY $1,000 $50,000 0.3 $15,000

    .4 Concrete (mass) 100 CY $1,000 $100,000 0.3 $30,000

    .5 Valve w/operator 1 LS $75,000 $75,000 0.3 $22,500

    .6 Sluice gate w/operator 1.0 LS $75,000 $75,000 0.3 $22,500

    .7 Misc. metals 1.0 LS $50,000 $50,000 0.3 $15,000

    333 WATERWHEELS, TURBINES AND GENERATORS

    .1 Supply LS $2,025,000 $2,025,000 0.3 $607,500

    .2 Install LS $250,000 $250,000 0.3 $75,000

    334 ACCESSORY ELECTRICAL EQUIPMENT

    .1 SWitchgear LS $300,000 $300,000 0.3 $90,000

    .2 Station Service LS $150,000 $150,000 0.3 $45,000

    .3 Control Panel LS $250,000 $250,000 0.3 $75,000

    .4 Cond uiUwires/cables LS $200,000 $200,000 0.3 $60,000

    .5 Power and controls to intake LS $250,000 $250,000 0.3 $75,000 Power and controls to Falls Creek

    .6 Diversion LS $100,000 $100,000 0.3 $30,000

    335 MISC. POWER PLANT EQUIPMENT

    Technical Memo #1 October 2009

  • Grant Lake and Falls Creek

    .1 Cooling Water System LS $25,000 $25.000 0.3 $7,500

    .2 Powerhouse crane LS $300,000 $300,000 0.3 $90.000

    336 ROADS, RAILROADS AND BRIDGES

    .1 Upgrade Existing Road 1.2 MI $50,000 $60,000 0.2 $12,000

    .2 New Road to Intake and Powerhouse 3.0 MI $250,000 $750,000 0.2 $150,000

    .3 New Road to Falls Creek Diversion 0.4 MI $250,000 $100,000 1.2 $120,000

    .4 Clearing/Drainage/Erosion Control LS $100,000 $100,000 0.3 $30,000

    350 LAND AND LAND RIGHTS ,1 Land rights - transmission line LS $10,000 $10,000 0.3 $3,000

    0,3 $-

    352 STRUCTURES AND IMPROVEMENTS (TRANSMISSION FACILITY)

    .1 Substation foundations 1 LS $50,000 $50,000 0.3 $15,000 ,2 Oil spill containment 1 LS $25,000 $25,000 0.3 $7,500

    .3 Grounding grid 2 LS $10,000 $20,000 0,3 $6,000

    353 STATION EQUIPMENT

    .1 Main transformer LS $157,500 $157,500 0.3 $47,250

    .2 Accessory switchgear equipment LS $350,000 $350,000 0.3 $105,000

    356 OVERHEAD CONDUCTORS & DEVICES .1 New pole line 0.8 MI $750,000 $600,000 0.2 $120,000

    Total Direct Construction Costs 23,300,000 $6,427,621

    Design Engineering 10% $2,330,000 0.2 $466,000

    FERC and other licensing $1,000,000 0.2 $200,000 Owner's General Administration & overhead 5% $1,165,000 0.2 $233,000

    Construction Management 5% $1,165,000 0.2 $233,000

    Subtotal $28,960,000 $7,559,621

    Interest during construction 8.0% $6,162,000

    2009 Estimated Project Cost $42,690,000

    Annual Energy, MWh 23,400

    Debt Service 8.0% $3,792,043

    O&M $639,600

    2009 Cost of Energy, $/kWh $0.189

    Assumptions:

    1 Financing and interest rates have been assumed at 8% per KHL guidance.

    2 The cost of energy is only a representative indicator to evaluate similar alternatives. The actual

    cost of energy will largely be a function of the financing ultimately arranged for the project.

    3 The effect of grant funding is not reflected in the cost of energy.

    GRANT LAKE

    Technical Memo #1 October 2009

  • Grant Lake and Falls Creek

    OPINION OF PROBABLE COST

    Alternative 3 Enhanced Storage

    Item Amount

    330 LAND AND LAND RIGHTS .1 Land Rights - Generation Plant LS $50,000 $50,000 0.3 $15,000

    .2 Special use permits LS $50.000 $50.000 0.3 $15.000

    .3 Surveying LS $100.000 $100.000 0.3 $30.000

    331 STRUCTURES AND IMPROVEMENTS .1 POWERHOUSE

    .1 Excavation 700 CY $150 $105.000 0.2 $21.000

    .2 Concrete (inc/. reinforcement) 390 CY $1.200 $468,000 0.2 $93.600

    .3 Metal Building 2700 SF $350 $945,000 0.2 $189.000

    .4 Misc. Metals LS $50.000 $50.000 0.3 $15.000

    .5 HVAC, Plumbing & Electrical LS $50.000 $50.000 0.3 $15,000

    .6 Grounding Grid LS $25.000 $25.000 0.3 $ 7,500

    .7 Fire Protection LS $25,000 $25,000 0.3 $ 7,500

    332 RESERVOIRS, DAMS AND WATERWAYS .1 SITE WORK

    .1 Clearing/Drainage/Erosion Control LS $50.000 $50.000 0.3 $15.000

    .2 DAM AND SPILLWAY .1 Excavation 330 CY $150 $49,500 0.3 $14.850 .2 Care of Water/Diversion 1 LS $250,000 $250,000 0.3 $75.000 .3 Concrete (structural) 0 CY $1.200 $- 0.3 $ -.4 Concrete (mass) 250 CY $1,000 $250.000 0.3 $75.000

    .3 INTAKE $ .1 Excavation 375 CY $150 $56,250 0.3 $16,875

    .2 Care of Water/Diversion LS $100.000 $100.000 0.3 $30,000

    .3 Trash racks LS $50,000 $50.000 0.3 $15,000

    .4 Control Gate w/operator 2 LS $100.000 $200,000 0.3 $60.000

    .5 Shutoff Gate w/operator 1 LS $150,000 $150,000 0.3 $45,000

    .6 Concrete (structural) 225 CY $1,500 $337,500 0.3 $101,250

    .7 Concrete (mass) 0 CY $1,000 $ 0.3 $ -

    .8 Misc. Metals LS $25,000 $25,000 0.3 $ 7,500

    .9 Misc. electrical & mechanical LS $100,000 $100,000 0.3 $30.000 0.10 Access Bridge LS $200,000 $200,000 0.3 $60.000

    .4 LOW LEVEL OUTLET

    .1 Excavation 300 CY $150 $45.000 0.3 $13.500

    .2 Concrete (structural) 90 LS $1.200 $108.000 0.3 $32.400

    .3 Valve w/operator LS $100,000 $100,000 0.3 $30.000

    .4 Misc. Metals LS $50,000 $50.000 0.3 $15.000

    .5 WATER CONDUCTORS AND ACCESSORIES

    Technical Memo #1 October 2009

  • Grant Lake and Falls Creek

    .1 PENSTOCK

    .a Clearing 0.7 ACRE $25,000 $18,652 0.3 $ 5,596

    .b Steel penstock material 650 LF $370 $240,500 0.2 $48,100

    .c Concrete (thrust blocks and supports) 150 CY $1,200 $180,000 0.3 $54,000

    .d Penstock installation 650 LF $250 $162,500 0.2 $32,500

    .e Slope stabilization 0.1 MI $250,000 $30,000 0.3 $ 9,000

    .f Surge tank LS $250,000 $250,000 0.3 $75,000

    .2 TUNNEL $

    .a Excavation 2800 LF $1,500 4,200,000 0.3 $1,260,000 $

    .b Tunnel Support 1400 LF $1,000 1,400,000 0.3 $420,000

    .c Lining 1400 LF $500 $700,000 0.3 $210,000

    .d Portals 2 EA $250,000 $500,000 0.3 $150,000

    .3 TAILRACE

    .a Excavation LS $75,000 $75,000 0.3 $22,500

    .b Support and lining LS $25,000 $25,000 0.3 $ 7,500

    0.3 $ -

    333 WATERWHEELS, TURBINES AND GENERATORS $

    .1 Supply LS $2,025,000 2,025,000 0.3 $607,500

    .2 Install LS $250,000 $250,000 0.3 $75,000

    334 ACCESSORY ELECTRICAL EQUIPMENT

    .1 Switchgear LS $300,000 $300,000 0.3 $90,000

    .2 Station Service LS $150,000 $150,000 0.3 $45,000

    .3 Control Panel LS $250,000 $250,000 0.3 $75,000

    .4 ConduiUwires/cables LS $200,000 $200,000 0.3 $60,000

    .5 Power and controls to intake LS $250,000 $250,000 0.3 $75,000

    335 MISC. POWER PLANT EQUIPMENT .1 Cooling Water System LS $25,000 $25,000 0.3 $ 7,500

    .2 Powerhouse crane LS $300,000 $300,000 0.3 $90,000

    336 ROADS, RAILROADS AND BRIDGES .1 Upgrade Existing Road 1.2 MI $50,000 $60,000 0.2 $12,000

    .2 New Road to Intake and Powerhouse 3.0 MI $250,000 $750,000 0.2 $150,000

    .3 Clearing/Drainage/Erosion Control LS $100,000 $100,000 0.3 $30,000

    350 LAND AND LAND RIGHTS .1 Land rights transmission line LS $10,000 $10,000 0.3 $ 3,000

    0.3 $ -

    352 STRUCTURES AND IMPROVEMENTS(TRANSMISSION FACILITY)

    .1 Substation foundations 1 LS $50,000 $50,000 0.3 $15,000

    .2 Oil spill containment LS $25,000 $25,000 0.3 $ 7,500

    .3 Grounding grid 2 LS $10,000 $20,000 0.3 $ 6,000

    353 STATION EQUIPMENT

    .1 Main transformer LS $157,500 $157,500 0.3 $47,250

    Technical Memo #1 October 2009

  • 356

    Grant Lake and Falls Creek

    .2

    .1

    Accessory switchgear equipment

    OVERHEAD CONDUCTORS & DEVICES New pole line

    Total Direct Construction Costs

    Design Engineering FERC and other licensing Owner's General Administration & overhead

    Construction Management

    Interest during construction

    2009 Estimated Project Cost

    Annual Energy, MWh

    Debt Service

    O&M

    2009 Cost of Energy, $/kWh

    Assumptions:

    Subtotal

    LS $350.000

    0.8 MI $750,000

    10%

    5%

    5%

    8.0%

    8.0%

    Financing and interest rates have been assumed at 8% per KHL guidance.

    $350.000

    $600,000

    $17,700,000

    $ 1,770,000

    $ 1,000,000

    $885,000

    $885,000

    $22,240,000

    $ 4,742,000

    $32,850,000

    19,000

    $ 2,917,981

    $572,400

    $0.184

    0.3 $105,000

    0.2 $120.000

    $4,959,921

    0.2 $354,000

    0.2 $200,000

    0.2 $177,000

    0.2 $177,000

    $5,867,921

    The cost of energy is only a representative indicator to evaluate similar alternatives. The actual cost of energy will largely be 2 a function of the financing ultimately arranged for the project.

    3 The effect of grant funding is not reflected in the cost of energy.

    Technical Memo #1 October 2009

  • Grant Lake Proposed Hydroelectric Project Reconnaissance Report

    Table of Contents

    Introduction .................................................................................................................................... 1

    Previous Studies ................................................................................................................... 1

    Project Area .......................................................................................................................... 2

    Environmental Considerations ..................................................................................................... 3

    Project Area Fish Resources ............................................................................................... 3

    Grant Lake Fish Resources .................................................................................................. 4

    Grant Creek Fish Resources ................................................................................................. 4

    Falls Creek Fish Resources .................................................................................................. 6

    Wetlands ................................................................................................................................ 7

    Hydrology and Water Quality ............................................................................................ 7

    Recreation ................................................ ~ ...................................................................................... 8

    Subsistence, Cultural and Historical Resources ........................................................................ 9

    Subsistence ......................................................... : ................................................................. 9

    Cultural and historic resources ......................................................................................... 10

    Land Ownership, Mining Claims, and Water Rights .............................................................. 1 0

    Alternative Project Arrangements ............................................................................................. 11

    Powerhouse Location ........................................................................................................ 12

    Active Storage .................................................................................................................... 12

    Alternative I: Run-of-River Project ................................................................................ 1 3

    Alternative 2: Impoundment ............................................................................................ 13

    Alternative 3: Impoundment + Drawdown ..................................................................... 13

    Alternative 4: Ebasco's 1984 Preferred Project ............................................................. 13

    Alternative 5: Impoundment + Drawdown + Falls Creek ............................................ 14

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance Report

    Summary of Alternatives .................................................................................................. 14

    Turbine Sizing .................................................................................................................... 14

    Other Alternatives Evaluated ........................................................................................... 15

    Energy Generation ....................................................................................................................... 15

    Assumptions ....................................................................................................................... 15

    Objective Function ............................................................................................................. 16

    Results ................................................................................................................................. 16

    Cost Estimates .............................................................................................................................. 16

    Results ................................................................................................................................. 18

    Economic Evaluation and Alternative Ranking ....................................................................... 18

    Conclusions and Recommendations .......................................................................................... 18

    References ..................................................................................................................................... 20

    Tables ........................................................................................................................................... 22

    Figures ........................................................................................................................................... 31

    Appendix A - Land Status Information .................................................................................... 46

    Appendix B - Energy Calculations ............................................................................................ 53

    Appendix C - Cost Information ............................................................ , ..................................... 59

    Appendix D - Project Photographs ............................................................................................ 73

    ii

  • Grant Lake Proposed Hydroelectric Project Reconnaissance YO.-.,.. .. ,

    List of Tables

    Table 1. Falls Creek scale factors (determined by APA 1984) used to simulate flow of Falls Creek from stream flow data collected at Grant Creek ........................ 23

    Table 2. Temperature comparisons for Grant Lake, Grant Creek and Falls Creek. Adapted from Table 2-8 in APA (1984) .......................................................... .24

    Table 3. 2008 instantaneous flow measurements collected by HDR staff, October to December 2008 ................................................................................................. 24

    Table 4. USFS campgrounds on the Kenai Peninsula ...................................................... 25 Table 5. USFS-maintained trails on the Kenai Peninsula ................................................. 25 Table 6. Parameters for all five alternatives considered. Elevations of maximum

    headwater (HW), minimum HW, tailwater elevation and net head (in feet) are given for each alternative. Design flow (cfs), capacity (MW), average inflow (cfs), and active storage are detailed for each project. ......................... .26

    Table 7. Seasonal energy valuation for hydroelectric projects. Seasonal variations in energy value are shown for an average water year* (after Table 17-1 of APA 1984) ........................................................................................................ 27

    Table 8. Energy generation estimate summary for the alternatives considered. Capacity (MW) and annual energy production (GWh) are shown for each alternative. The modeled plant factor and seasonal benefit are also given for each alternative. For details of energy calculations, see Appendix B. ...... .28

    Table 9. Reconnaissance-level cost estimates for all alternatives. Rated capacity (MW) and estimated project cost are presented fore each alterative in millions of dollars (For details of cost estimates, see Appendix C ................... 29

    Table 10. Estimated energy cost ($IKWh), economic rank and environmental rank of all alternatives considered ................................................................................. 30

    iii

  • Grant Lake Proposed Hydroelectric Project Reconnaissance Report

    List of Figures

    Figure 1. General location of proposed hydroelectric facilities at Grant Lake on the Kenai Peninsula, Alaska ................................................................................... 32

    Figure 2. The anadromous reach of Grant Creek (section of stream in which anadromous fish are documented by the AWC; Johnson and Daigneault 2008) ................................................................................................................. 33

    Figure 3. The anadromous reach of Falls Creek .............................................................. .34 Figure 4. Average monthly flow data at Grant Creek. Average annual flow (for

    period of record 1947-1958, from USGS gauge #5246000) is shown as a solid horizontal line (193 cfs) .......................................................................... .35

    Figure 5. Flow duration curve for Grant Creek ................................................................ 35 Figure 6. Mean monthly discharge of Falls Creek, modeled using data from USGS

    gage 15246000 (1947-1958) at Grant Creek, adjusted by monthly ratios developed by Ebasco (APA 1984; using one open water season of flow data. at Falls Creek) ........................................................................................... 36

    Figure 7. Flow duration curve for Grant Creek. Percent exceedence, the value of the x-axis, is the percent of the time flow surpasses the value on the y-axis ......... .37

    Figure 8. Grant Creek discharge data ............................................................................... 38 Figure 9. Falls Creek modeled discharge based on data from USGS gauge 15246000

    (1947-1958) at Grant Creek, adjusted by monthly ratios developed by Ebasco (APA 1984) using one open water season of current flow data ........... 39

    Figure 10. Private Parcels near Grant Lake ..................................................................... .40 Figure 12. Private parcels of Falls Creek area ................................................................. .41 Figure 13. Water rights and mineral claims in the Grant Lake area ................................ .42 Figure 14. Water rights and mineral claims in the Grant Lake area ................................ .43 Figure 15. Alternative 1 for propos project at Grant Lake .............................................. .44 Figure 16. Maximum energy analysis for Alternative 3 (impoundment and

    drawdown) during an average water year ........................................................ .45

    IV

  • ADF&G AEIDC AHRS APA AWC BLM C cfs em of

    DNR EPA FERC fps ft G&A GWh HEP in KPB kWh LLC mt mm MSL MW MWh NWI O&M RVDs USACE USFS USFWS USGS

    Grant Lake - Proposed Hydroelectric Project Reconnaissance

    Acronyms and Abbreviations

    Alaska Department ofFish and Game Arctic Environmental Information and Data Center (University of Alaska) Alaska Heritage Resources Survey Alaska Power Authority Anadromous Waters Catalog Bureau of Land Management Degrees Celsius Cubic feet per second centimeter Degrees Fahrenheit Alaska Department of Natural Resources Environmental Protection Agency Federal Energy Regulatory Commission feet per second feet general and administrative Gigawatt-hours Hydroelectric Evaluation Program inch Kenai Peninsula Borough kilowatt-hours Limited liability company mile millimeter Mean sea level Megawatt Megawatt-hours National Wetlands Inventory Operations & maintenance Recreation visitor days U.S. Army Corps of Engineers U.S. Forest Service U.S. Fish and Wildlife Service U.S. Geological Survey

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  • Grant Lake Proposed Hydroelectric Project Reconnaissance

    Introduction

    Kenai Hydro LLC contracted with HDR Alaska, Inc. to evaluate the feasibility of small-scale hydroelectric projects at Crescent Lake, Ptarmigan Lake, Falls Creek, and Grant Lake near Moose Pass, Alaska (Figure 1).

    This reconnaissance report examines the viability of several alternatives for small-scale hydroelectric energy generation at Grant Creek that would minimize environmental and other impacts. A team consisting of engineers and environmental scientists made reconnaissance-level site visits and analyzed existing information in order to determine if further feasibility analyses were appropriate based on potential constructability, cost effectiveness, and potential environmental impacts.

    The scope of work defined for this assignment included:

    Field reconnaissance by team members;

    Review of available project documentation and related information;

    Development of conceptual alternatives;

    Review of existing hydraulic and hydrologic parameters;

    Estimation of energy production and new facility costs;

    Preparation of this reconnaissance report.

    This report should be considered a high-level overview intended to identify projects which demonstrate a basic measure of feasibility and to eliminate projects that have evident fatal flaws from an engineering and/or economic perspective.

    Previous Studies

    The hydroelectric potential at Grant Lake (Figure 1) has been evaluated several times as a potential power source for the SewardlKenai Peninsula area. In 1954, R.W. Beck and Associates (cited by APA 1984) prepared a preliminary investigation and concluded that a project was feasible. The U.S. Geological Survey (USGS) conducted geologic investigations of proposed power sites at Cooper, Grant, Ptarmigan, and Crescent Lakes in the 1950s (Plafker 1955). In 1980 CH2M Hill (cited by APA, 1984) prepared a pre-feasibility study for a Grant Lake project and concluded that a project developed at the site would be feasible. The Grant Lake Project was referenced in the 1981 U.S. Army Corps of Engineers (USACE) National Hydroelectric Power Resources Study (USACE 1981). The most extensive study was performed by Ebasco Services, Inc. in 1984 for the Alaska Power Authority (now Alaska Energy Authority; APA 1984). Two of the alternatives evaluated by Ebasco included the diversion of adjacent Falls Creek into Grant Lake to provide additional water for power generation. This report relies on the Ebasco report for the basis of the current technical conclusions with regard to hydrology, geotechnical, and environmental considerations.

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance "n'-Jr. .. '

    The Ebasco report evaluated six project alternatives and concluded that the preferred alternative was a 7 megawatt (MW) hydroelectric project (Alternative D from APA 1984) that consisted of a lake-tap intake on the west shore of Grant Lake connected by a tunnel to a powerhouse located at the narrows between Upper and Lower Trail Lakes. The project would make use of approximately 48,000 acre-feet (AF) of storage during operations between pool elevations of 691-660 feet (ft). Average annual energy from the project was estimated at 25 gigawatt-hours (GWh). The estimated capital cost was $24.7 million in 1983 dollars. The benefit-cost ratio was 1.2.

    The Alaska Power Authority (APA) and Ebasco conducted detailed environmental studies of water use and quality; aquatic, botanical and wildlife resources; historical and archaeological resources; socioeconomic impacts; geological and soil resources; recreational resources; aesthetic resources; and land use. The primary environmental impact of Ebasco's preferred project would have been the complete dewatering and subsequent loss of all fish habitat in Grant Creek (natural outflow from Grant Lake; APA 1984). Under this alternative, Grant Creek would have been completely dewatered except for localized run-off and high flow events resulting in spill from the reservoir (APA 1984).

    Project Area

    The project is located near the town of Moose Pass, Alaska (pop. 206), approximately 25 miles north of Seward, Alaska (pop. 3,016), just east of the Seward Highway (State Route 9); this highway connects Anchorage (pop. 279,671) to Seward. The Alaska Railroad parallels the route of the Seward Highway, and is also adjacent to the project area. The town of Cooper Landing is located 24 miles to the northwest and is accessible via the Sterling Highway (State Route 1) which connects to the Seward Highway approximately 10 miles northwest of Moose Pass.

    Grant Lake is located approximately 1.5 miles southeast from Moose Pass. It is located at an elevation of approximately 696 ft above mean sea level (MSL), with a maximum depth of nearly 300 ft and surface area of 2.6 square miles (APA 1984). Grant Lake's total drainage area is approximately 44 square miles. Tributaries include Inlet Creek at the headwaters and other glacial-fed streams in the watershed. Grant Lake consists of an upper and lower portion separated by a natural constriction and island near the midpoint. The lake is ringed by mountains of the Kenai Mountain Range to the east, north, and south, with elevations ranging from 4, 500 to 5,500 ft.

    Grant Lake supports resident populations of sculpin (Cottidae) and threespine stickleback (Gasterosteus aculeatus), but salmon were not caught in Grant Lake or any of its tributaries during environmental assessments (USFWS 1961; AEIDC 1982; APA 1984); it is not included in the Anadromous Waters Catalog (A WC) published by Alaska Department of Fish and Game (ADF&G; Johnson and Daigneault 2008).

    Grant Lake's only outlet, Grant Creek, runs west approximately 1 mile from the south end of Grant Lake to drain into the narrows between Upper and Lower Trail Lake. Trail River drains Lower Trail Lake, and then flows into Kenai Lake. Kenai Lake drains to the Kenai River at its west end near Cooper Landing (APA 1984). Grant Creek has a mean annual flow of 193 cubic feet per second (cfs; see Hydrology and Water Quality below), is 5,180 ft long, with an average gradient of 207 ftlmi; its substrate includes cobble and boulder alluvial deposits and gravel

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  • Grant Lake Proposed Hydroelectric Project Reconnaissance Report

    shoals (APA 1984). The stream is 25 ft wide on average. In its upper half, the stream passes through a rocky gorge with three substantial waterfalls; in its lower half, the stream becomes less turbulent as it passes over gravel shoals and diminishing boulder substrate (APA 1984). Grant Creek is included in the A WC due to the presence of spawning Chinook, sockeye and coho salmon and rearing coho salmon (Johnson and Daigneault 2008).

    Falls Creek is located approximately 2 miles south of the south end of Grant Lake; it flows into Trail River just downstream of Lower Trail Lake (approximately 1.8 miles downstream of Grant Creek). The Falls Creek watershed drains steep terrain between the Grant Lake and Ptarmigan Lake watersheds, is 11.9 square miles in area, contains no lakes, and has no major tributaries. Estimated mean annual flow of Falls Creek is 38 cfs; stream flow during the winter is minimal. Falls Creek is 42,240 ft (approx. 8 miles) long, average stream gradient is 418 ftlmi and stream width averages 15 ft wide. The Falls Creek substrate includes cobble, boulder deposits, few gravel bars and a thin layer of fine silt near the mouth; the lower one mile of stream has been extensively channelized and modified by placer mining (APA 1984). Three to four acres adjacent to the active channel in the lower 0.5 miles are covered with tailings and 100 yards of the streambed in this area has been relocated (AEIDC 1982).

    The lower 2,300 ft of Falls Creek is classified as anadromous in the A WC (Chinook present; Johnson and Daigneault 2008). Anadromous species Guvenile Chinook and juvenile Dolly Varden) have been found in its lower half; a series of waterfalls prevents fish passage above that point (Johnson and Daigneault 2008; AEIDC 1982).

    Environmental Considerations

    The following presents a general overview of potential expected environmental considerations for a hydroelectric project at Grant Lake. This section describes fish resources, wetlands, hydrology and water quality, recreation, subsistence, and cultural resources of the project area. The area is managed using several specific management plans, including the Chugach National Forest Plan (Meade 2006), Kenai River Comprehensive Management Plan (DNR 1998), and Kenai Borough Coastal Management Plan (KPB 2008). Another search for all relevant land management plans would be required as part of FERC licensing and by other required permitting processes.

    Ebasco (APA 1984) compiled a detailed feasibility report on the Grant Lake hydroelectric project, including environmental issues. The Arctic Environmental Data Center (AIEDC 1982) and USFWS (1961) conducted environmental baseline studies in the project area. For the purposes of this feasibility report, HDR Alaska did not conduct any environmental work beyond initial reconnaissance visits and a few instantaneous flow measurements (see Hydrology and Water Quality below).

    Project Area Fish Resources

    Grant Lake, Grant Creek and Falls Creek support different assemblages of fish species and possess varying quality and quantity of fish habitat. Only non-anadromous fish have been found in Grant Lake (AIEDC 1982, USFWS 1961, Johnson and Daigneault 2008), whereas

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  • Grant Lake - Proposed Hydroelectric Project Reconnaissance

    anadromous fish are present in Grant and Falls Creeks (Figure 2). The following sections provide information on fish resources for each water body.

    Grant Lake Fish Resources

    Grant Lake is divided into upper and lower basins by a narrow shallow area, preventing effective mixing between the basins (Figure 1). Limited mixing results in the upper basin being more sediment-laden than the lower basin. The shoreline of Grant Lake is made up of slopes of steep bedrock with isolated small gravel deposits formed by runoff (APA 1984).

    A 1981-1982 sampling program found no fish in any of the tributaries of Grant Lake (AEIDC 1982). Sculpin and threespine stickleback were the only fish found to inhabit Grant Lake. A series of impassable falls l near Grant Lake's outlet prevents colonization of the lake by salmonids via Grant Creek (APA 1984).

    Grant Lake supports a "small" population of slimy sculpin (Cottus cognatus) and a "dense" population of threespine stickleback (USFWS 1961). Density of threespine stickleback was ten times higher in the lower basin than the upper basin of Grant Lake (AEIDC 1982).

    Grant Creek Fish Resources

    Both anadromous and resident fish are present in Grant Creek, including salmon, trout and other fish. Spawning Chinook (Oncorhynchus tshawytscha), sockeye (Oncorhynchus nerka), and coho salmon (Oncorhynchus kisutch), as well as rainbow trout (Oncorhynchus mykiss) and Dolly Varden are found in the lower reaches of Grant Creek (APA 1984; Johnson and Daigneault 2008). Rearing Chinook, coho and rainbow trout are also present (AP A 1984, Johnson and Daigneault 2008). Round whitefish (Prosopium cylindraceum) and Arctic grayling (Thymallus arcticus) were caught during angling surveys, but not assumed to spawn in Grant Creek (AP A 1984).

    Upper Grant Creek is impassable to salmon one half (APA 1984) to one mile (Johnson and Daigneault 2008) upstream of the mouth; fish habitat is most likely concentrated within the lower portion of stream. Habitat for juvenile fish exists mainly in stream margins, eddies, deep pools and side channels offering reduced velocities (APA 1984). Substrate material is coarse throughout the entire length of the creek due to high water velocity, which tends to wash away smaller gravels. Isolated areas of suitable spawning gravels occur in the lower half of the stream (APA 1984).

    Periodic minnow trapping on Grant Creek from July 1959 through January 1961 captured Chinook salmon, coho salmon, Dolly Varden and SCUlpin (extent of sampling area unknown; USFWS 1961). Minnow trapping and electrofishing in lower reaches of Grant Creek for week-long periods in October 1981 and March, May, June, and August 1982 yielded higher catches of trout, salmon and Dolly Varden in the fall and summer than in winter and spring (AEIDC 1982 in APA 1984; AIEDC 1983). Catches of Dolly Varden were generally most abundant in minnow

    12007 ADFG Stream survey referenced in Anadromous Waters Catalog Stream Nomination #08-153, http://www.sf.adfg.state.ak.us/SARRIFishDistriblNominationIFDDNomHome.cfm

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  • Grant Lake - Proposed Hydroelectric Project Reconnaissance wn>4,,, .. r

    traps, followed by juvenile Chinook, juvenile rainbow trout, and juvenile coho. Juvenile Chinook were the most commonly caught fish during electrofishing surveys (APA 1984).

    Fish may delay one to two months between entry into the Kenai River and arrival at Grant Creek, previous studies have concentrated efforts of spawning surveys from mid August and early September (APA 1984).

    AP A (1984) estimated that Grant Creek supported 250 Chinook spawners and 1,650 sockeye spawners (APA 1984). These estimates were likely biased low due to visual counting methods. The stream was also estimated to support 209 8-inch "trout" (including Dolly Varden and rainbow trout; APA 1984). Spawning coho were not surveyed (APA 1984), but have been recorded as being present at unknown levels in the stream by the A WC (Johnson and Daigneault 2008). Maximum counts from intermittent stream surveys by ADFG were 76 Chinook (1963) and 324 (1952) sockeye salmon?

    In 1984, less than 500 angler-days of fishing were estimated for rainbow trout, Dolly Varden and whitefish (APA 1984). Current 2009 sport fishing regulations allow sport fishing on Grant Creek June 11 - May 1. Grant Creek is closed to all salmon fishing. Rainbow trout are limited to one fish less than 16 inches long per day. Dolly Varden are limited to one fish less than 16 inches long per day.3 Current sport fishing effort is unknown.

    Chinook salmon

    Typically, Chinook returning to Grant Creek were part of the early season salmon run (May through late June; APA 1984) which is characterized by salmon that tend to spawn in tributaries (Boggs et al. 1997). Chinook juveniles were observed most often in the lower part of the creek, but during October (1981) were distributed throughout the creek from the mouth of the gorge to the stream mouth at Trail Lake. Fish caught in March, May and June were greater than 65 mm (2.6 in), suggesting they would probably smolt in June (APA 1984). Juvenile Chinook were the second-most abundant fish after Dolly Varden in minnow trap catches (APA 1984). Juvenile Chinook were present year-round in minnow trap surveys, but in low numbers in March, May, and June, suggesting they were either very inactive during these months or had left the system to rear elsewhere prior to downstream migration (APA 1984); these fish may have reared in Trail River or Kenai Lake. Rearing in Trail Lakes is assumed unlikely due to the high turbidity of the lakes (Dudiak 1980). Natural emergence may have been later than June because no young of the year were captured in minnow traps until August, but this could have been caused by gear bias; young of the year were caught during electrofishing surveys in May, though they may have been stimulated out of the gravel by electrofishing (APA 1984).

    2Anadromous Waters Catalog Stream Nomination #08-153, http://www.sf.adfg.state.ak.us/SARRlFishDistriblNominationIFDDNomHome.cfm

    3 http://www.sf.adfg.state.ak.uslstatewide/regulations/southcentral/SCkenai .pdf

    5

    http://www.sf.adfg.state.ak.uslstatewide/regulations/southcentral/SCkenaihttp://www.sf.adfg.state.ak.us/SARRlFishDistriblNominationIFDDNomHome.cfm

  • Coho salmon

    Grant Lake Proposed Hydroelectric Project Reconnaissance Report

    Surveys found juvenile coho to use Grant Creek for rearing, but that they were present in small numbers (APA 1984). Coho were caught nearly exclusively in the lower part of the stream, but were low in abundance. Length (40 mm [ 1.6 in]), of several fish caught in August 1982 suggested that coho spawn in Grant Creek, since juvenile coho do not generally venture far from their natal areas, and flow at the mouth of Grant Creek is very rapid (APA 1984). Older, larger coho were thought to be recruited into Grant Creek from the turbid waters of Trail Lake since fish up to 103 mm (4.2 in) were caught (APA 1984).

    Sockeye salmon

    Peak counts averaged 61 sockeye salmon for the years 1952-1981, but these counts were probably underestimates due to infrequency of spawning surveys (e.g. foot surveys) and poor visibility due to high turbidity and high discharge rates (APA 1984). No juvenile sockeye were caught in minnow trapping or electrofishing efforts (APA 1984).

    Rainbow trout

    Rainbow trout were evenly distributed in the lower reaches of Grant Creek and ranged from 43 to 106 mm in length (1.8 to 4.2 inches). Catches were greatest in October (including many young of the year), suggesting spring spawning may occur in Grant Creek. Many of these young of the year may have moved upstream from the Trail Lakes area to rear and are generally inactive during the winter months (AP A 1984).

    Dolly Varden

    Dolly Varden were more abundant near the mouth of Grant Creek, except in August, when they were distributed throughout the lower creek. No spawning Dolly Varden were observed. It is possible that the high abundance of fish in August may be a result of fish moving into Grant Creek to feed and avoid high turbidity (APA 1984). A variety of size classes of Dolly Varden were caught (55mm to 30cm [2.2 to 11.8 in]; APA 1984).

    Falls Creek Fish Resources

    Anadromous fish are present in Falls Creek (Figure 3), The most information on fish is available for Grant Creek, the only water body in the area possessing documented runs of spawning anadromous fish. Current 2009 sport fishing regulations allow sport fishing on Falls Creek June 11 May 1. Falls Creek is closed to all salmon fishing. Rainbow trout are limited to one fish less than 16 inches long per day. Dolly Varden are limited to one fish less than 16 inches long per day4, Current sport fishing effort is unknown.

    The following provides information on fish resources of Falls Creek. Previous investigators suggested that Falls Creek may have limited salmon spawning potential in the lower mile of Falls Creek due to low water temperatures that may limiting its production; this was supported

    4 http://www.sf.adfg.state.ak.uslstatewide/regulations/southcentral/SCkenai.pdf

    6

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  • Grant Lake - Proposed Hydroelectric Project Reconnaissance ",orln>"1

    by a lack of observations of spawning salmon during week-long field visits in October 1981 and March, May, lune, and August 1982 (AEIDC 1982 and 1983). Instream cover available to juvenile fish consists of debris jams and a few cutbank meanders (AEIDC 1982). In 1960 minnow trapping, juvenile Chinook were only caught in the lower 200 yards of the stream, though traps were set from the mouth to one mile upstream (months sampled: lune-November; USFWS 1961).

    Wetlands

    Most bogs in the project area exist on the ridge separating Lower Trail Lake from Grant Lake. Others exist in areas of low relief in mixed and coniferous forests (APA 1984). These wet meadow range from extremely wet, floating mats to firm, treed bogs with many shrubs. Many of the bogs have a wet spot or small pond in the center (APA 1984). No information exists in historical reports for the Falls Creek area regarding wetlands. No additional investigation of wetlands was performed for the purposes of this feasibility report. Data regarding wetlands resources in the project area are available from the National Wetlands Inventory (NWI) mapping system; this type of detailed assessment was outside the scope of this reconnaissance-level report.

    Hydrology and Water Quality

    In 1947, the USGS installed a stream gage (#15246000) approximately 0.3 miles upstream of the mouth of Grant Creek. This gage recorded continuously for II years between 1947 and 1958 (average annual flow was 193 cfs; drainage area at gage site is 44.2 square miles; Figure 4). Flow was generally lower in the winter months (December through April,

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance f{1'T.IOrl

    neutral in pH, soft and low in suspended and dissolved solids. Grant Lake was found to be oligotrophic (low in nutrients), typical of similar lakes in southcentral Alaska (APA 1984).

    Grant Lake was thermally stratified in August and September, although a sharply defined thermocline was not observed. Summer temperatures ranged from 14C (57F) at the surface to 5C (41F) at 98 ft deep. Fall overturn commenced in mid-September 1982 and October 1981. In March 1982, an inverted thermocline was present, with temperatures ranging from 2C at the ice/water line to 4C (39F) at 9.8 ft deep. Spring overturn was complete by June, with an isothermal profile at approximately 6C (43F; APA 1984).

    Historical Grant Creek temperatures ranged from 13 to OC (55 to 32F), with temperature closely related to Grant Lake surface temperatures (maximum difference was less than 1.7C; Table 2). Falls Creek was generally colder than Grant Creek, ranging from 7.0C (12.6F) colder in July, 1959, to 2.5C (4.5F) colder in October 1981 (APA 1984; Table 2). Water quality of Falls Creek was typical of low-productivity Kenai Peninsula area streams (AEIDC 1982).

    HDR Alaska gathered instantaneous discharge data at Grant Creek on October 4, October 23, and December 3, 2008. Stream discharge measurements were taken just downstream of the original site of the USGS stream gauge, at a site that allowed safe fording of the stream, using standard USGS gauging protocols (Buchanan and Somers 1969; 3). Measurements from 2008 were compiled with historical discharge data from USGS Gage 15246000 (1947-1958; Figure 8). Wetted stream width ranged from 35.0 (October 4,2008) to 38.9 ft (December 3,2008; Table 3).

    Stream flow and stream widths were measured at Falls Creek on October 5 and October 24, 2008 (Table 2). Measurements were taken at a site approximately 100 ft downstream of the Seward Highway Bridge. Falls Creek modeled discharge data were compiled with field measurements from 2008; data were generated from USGS gauge 15246000 (1947-1958) at Grant Creek and adjusted by monthly ratios developed by Ebasco (APA 1984) using one open water season of current flow data from Falls Creek (Figure 9).

    Recreation

    Lands in the project area are predominantly undeveloped, with high scenic and recreational value. The Kenai Peninsula supports significant tourism from residents of the region, of Anchorage, of Alaska and from outside of Alaska. Kenai Peninsula Borough Coastal Management Plan (KPB 2008) includes Grant Creek/Grant Lake as a designated recreation use area.

    The U.S. Forest Service (USFS) administers Chugach National Forest, which surrounds most of the project area; Grant Lake is located within the Seward ranger district. Peak use of area campgrounds (Table 4) coincides with salmon runs (APA 1984). Total recreational use in the campgrounds in 1981 was estimated at 442,400 recreation visitor days (RVDs), representing 40% of 1.1 million total RVDs for the entire Chugach National Forest (APA 1984).

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  • Grant Lake - Proposed Hydroelectric Project Reconnaissance HOYllu't

    The project area currently is not developed for recreation, with the exception of a few of trails developed by users but not maintained by USFS. These informal trails consist oftrails from both Upper and Lower Trail Lakes to Grant Lake, snow machine trails to Grant Lake and a primitive road to mining claims on Falls Creek. Only the Vagt Lake trail is maintained as part of the US FS trail system; Vagt Lake is stocked with rainbow trout for recreational fishing (AP A 1984). Other USFS-maintained trails on the Kenai Peninsula are shown in Table 5.

    More detailed information assessing recreational use of the project and adjacent areas is needed in order to comply with requirements of the Federal Energy Regulatory Commission (FERC) license application. Detailed user data are available upon request from the USFS, but inclusion and analysis of these data were outside the scope of this reconnaissance-level report.

    The project area received limited recreational use such as fishing, hunting, hiking, backpacking and camping, mostly in spring and summer. Hunters occasionally canoe on Grant Lake. Snowmobiles also utilize the area in winter (APA 1984), The project lies within the Ptarmigan/Grant Lake subunit of Chugach National Forest for backcountry motorized winter use, and receives very little use from any winter user group (motorized or non-motorized; Meade 2006). Helicopter skiing is permitted in the Ptarmigan/Grant Lake subunit (Meade 2006). Principle recreation attractions are hunting, fishing, and opportunity for experiencing the backcountry (APA 1984). Game animals present in the area were: mountain goat, black bear, brown bear, Dall sheep, and moose (APA 1984). Float plane and foot travel were the only means of access to hunting areas such as the east end of Grant Lake (APA 1984). Recreational fishing for Dolly Varden and rainbow trout was limited to the lower portion of Grant Creek and is also limited by difficult access, either by boat via Trail Lakes or by hiking several miles from the highway (APA 1984).

    Estimates of recreational use within the project area or in the project vicinity are limited to USFS statistics on use of Vagt Lake Trail (a two-hour round trip hike), which received an estimated 500 RVDs in 1981 (unpublished data, Chugach National Forest cited by APA 1984). In 1981, a hiking trail paralleled Vagt Creek to lower Trail Lake and appeared to be well used (AEIDC 1982). AEIDC (1981) reported sport fishing in the creek to be poor due to its small size and placement of barriers to prevent fish outmigration from Vagt Lake.

    Backpackers were observed camping at Grant Lake in the 1980s, mostly at the northern end of the lower basin, but the USFS had not estimated use during the 1980s (APA 1984; it is not known whether the USFS currently tracks usage of Grant Lake). APA (1984) estimated 72 RVDs per year for Grant Lake based on two backpacking parties per month, an average party size of three people, a four month backpacking season, and an average stay of 36 hours (APA 1984).

    Subsistence, Cultural and Historical Resources

    Subsistence

    Grant Creek, Grant Lake, and the surrounding areas are not designated a subsistence use area by the Kenai Peninsula Borough Coastal Management Plan (KPB 2008). Qualified residents of Cooper Landing may harvest moose in game units 7, 15A and 15B on the Kenai Peninsula under

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  • Grant Lake - Proposed Hydroelectric Project Reconnaissance Report

    Federal subsistence regulations5 (Grant Lake is located in game unit 7.) Federally-qualified subsistence users of Cooper Landing are also allowed to take salmon through a dip net/rod-and-reel fishery, and lake trout, Dolly Varden, and rainbow trout in the Kenai River through a rod-and-reel fishery6. A more detailed analysis of subsistence uses of the project area will be required by FERC licensing and other pennitting processes.

    Cultural and historic resources

    Based on a preliminary investigation of Alaska Heritage Resources Survey (AHRS) data at the State Office of History and Archaeology, 65 cultural resource sites have been documented in the general vicinity of Grant Lake, Falls Creek, and Ptannigan Lake. Several of the sites are listed on or eligible for the National Register of Historic Places. Most cultural resource sites are located along Upper and Lower Trail lakes and Trail River. Several mining-related sites are located in the area between Falls Creek and Grant Lake. A more detailed review of cultural and historic resources of the project area will be necessary to comply with requirements of the FERC license application process.

    Land Ownership, Mining Claims, and Water Rights

    HDR real estate specialists researched public land, private holdings (Figures 10 and II), mineral claims and water rights (Figures 12 and 13) of the Grant Lake and Falls Creek areas using infonnation from Alaska Department of Natural Resources (DNR) land status maps? arid case file abstracts8, the Bureau of Land Management (BLM)9, the State Recorder's Office lO and Kenai Peninsula Borough II. A detailed investigation of private land holdings, mining claims and water rights will be integral in identifying stakeholders in the pennitting process.

    All lands on which project facilities would be located are under either State or Federal ownership (Figures 10 and 11). No private lands are known to overlap with project facility footprints. Private property (33 parcels; Figure 11) is located along the Seward Highway and the lower portion of the Falls Creek access road.

    HDR real estate specialists investigated both State and Federal mining claims (Figures 12 and 13). It will be necessary to work closely with StatelFederal agencies and the claim holders. Ideally, recreational mining claims would be extinguished by paying a negotiated amount; however it is conceivable that the price for a claim could depend on provable grade and quantity

    5 http://alaska.fws.gov/asm/newsreVr050208.html

    6 http://alaska.fws.gov/asmlnewsrel/r051107.html

    7 http://mapper.1andrecords.info/

    8 http://dnr.alaska.gov/projectsllasllasmenu.cfin

    9 http://sdms.ak.blm.gov/sdmsl

    10 http://dnr.alaska.gov/ssdlrecofflsearch.cfin

    II http://www.borough.kenaLak.us/assessingdeptl

    10

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  • Grant Lake Proposed Hydroelectric Project Reconnaissance Wnrln .. '

    of the locatable mineral. A records search found four mining claims to the north of Grant Lake (Figure 12; see Appendix A for more information).

    As of 1984, Falls Creek was used extensively for placer mining during summer months. Land adjacent to Falls Creek is almost continuously claimed for placer mining from 1,300 ft elevation to the mouth for the creek. Mining claims (Figure 13) are located both along Falls Creek and on hillsides of the drainage (15 federal mining claims and four state mining claims within the project area). Several of these claims were seen during site visits and are located in the vicinity of the preferred intake site (Figure 13; see Appendix A for more information).

    Neither Grant Creek nor Grant Lake is currently used for domestic water supply. In the 1980s, a seasonal mining operation existed on the north shore of Grant Lake's lower basin. Water from streams feeding the lake is used for placer mining; a small amount of this water is presumably used for domestic purposes (APA 1984). APA (1984) reported that this mining operation holds a permit for use of 0.36 cfs to be taken from Grant Lake and an unnamed stream flowing into Grant Lake. No domestic use of water from Grant Creek occurs, though the lower half mile is recreationally fished (APA 1984). HDR's search of official records yielded no documented water rights within the Grant Lake drainage (Figure 12; see Appendix A for detailed information on water rights); more detailed research into water rights is warranted.

    A search of official records found that the Falls Creek project area contains one subsurface water right at its far west end (Figure 13). APA (1984) noted that several cabins were located within 2 miles of the mouth of Falls Creek and operated under USFS special use permits; water was likely carried in from outside the project vicinity. A water right of 1 cfs was reported (for placer mining on Falls Creek at 1200 ft elevation; APA 1984). As with the Grant Lake area, more detailed research of water right in the Falls Creek area is warranted.

    Alternative Project Arrangements

    In the past, several different alternatives were proposed to produce hydroelectric power at Grant Lake. This section of the report revisits the preferred alternative from 1984 (APA 1984) and presents additional new configurations. The following alternatives were considered:

    Alternative 1 - Run-of-river

    Alternative 2 - Low head intake structure

    Alternative 3 - Low head intake structure and drawdown

    Alternative 4 - Lake tap, tunnel and powerhouse located on Trail Lake (1984 preferred alternative)

    Alternative 5 Low head intake structure, drawdown, and diversion of Falls Creek

    All new alternatives assumed that a powerhouse would be located on Grant Creek at elevation 530 ft (which is to be verified with better topography is located near the boundary of high and low quality fish habitat; Figure 2). Each new alternative has a different amount of active storage.

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  • Grant Lake ~ Proposed Hydroelectric Project Reconnaissance Report

    Powerhouse location and active storage are discussed below. Our assumption was that any project would require a low-level outlet at the natural outlet to Grant Lake to release flows into Grant Creek in times of plant outages. Each alternative considered is discussed below.

    Powerhouse Location

    In 1984, Ebasco (APA 1984) completed a detailed feasibility analysis and concluded that the powerhouse should be located approximately Yz mile north of the point where Grant Creek enters the Trail Lake system (Figure 1). With this configuration, flow would have been completely diverted from Grant Creek. To offset negative impacts to Grant Creek fish, the APA (1984) study proposed off-site mitigation at a location other than Grant Creek.

    In the last 25 years, the regulatory climate has changed dramatically. In particular for hydroelectric projects, fish resources have become one of the major issues for proposed projects to address. The resource agencies almost always require diverted flows to be returned to the original source as close as possible to the anadromous barrier (if one exists). In the case of storage projects, instream flow requirements are almost always required for fish.

    It is extremely unlikely that the preferred alternative from APA (1984) would be viable today due to the flow restrictions that would be placed on operations. Preliminary estimates are that energy generation of this alternative could be reduced by 40-70% from what has been previously assumed due to these requirements.

    This study assumes that any new powerhouse would be located on or near Grant Creek so all diverted flows are returned back to Grant Creek. A detailed fisheries assessment is beyond the scope of reconnaissance-level study but for the purposes of defining alternatives, the anadromous fish barrier and subsequently the tailwater elevation was assumed to be at elevation 530 ft (Figure 2). This elevation will be confirmed with more detailed topographic mapping when available.

    Active Storage

    With any hydroelectric project, energy generation will increase and operational concerns will ease if storage of water is possible in comparison to the same project operating in a run-of-river mode. The initial amount of storage to capture this benefit is usually small in comparison to the annual yield of the basin. This operational storage may only be equivalent to a few minutes, hours or days of operation.

    Active storage in excess of operational storage would allow the ability to seasonally shift generation by capturing high flows (that might otherwise have passed as spill) and release this water later in the year (to supplement low natural flows). Thus, the cost of providing storage above the operational requirement needs to be offset by the increase in generating revenue that comes from seasonally shifting the generation.

    The seasonal benefit of generation is much easier to define in isolated power grids where often the new hydroelectric project is the prime generator. In the case of Grant Lake, the project would be a small component of a complex integrated system. Determination of the seasonal

    12

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance Report

    characteristics of the market, and thus the benefits, can be a significant task and is beyond the scope of this study. However, in this evaluation we did assume that a seasonal benefit would exist in some form to allow comparison of alternatives with storage and without.

    For a Grant Lake project, active storage could be accomplished with a siphon or lake tap intake that allows for drawdown, a structure which provides impoundment or a combination of the two.

    Alternative 1: Run-of-River Project

    Alternative 1 is considered the base case and would be comprised of a simple diversion structure or intake located at the natural outlet to Grant Lake (Figure 14). A sluiceway capable of releasing incremental flows (should the plant be taken offline) and a spillway would be located next to the intake. An above-ground steel penstock supported on saddles would convey water to the powerhouse (Figure 14). Water velocity was limited to 12 feet per second (fps) in determining the size of the penstock. A surge tank was assumed to be needed, and would be located near the top of the slope. A concrete-reinforced powerhouse structure would contain a single Francis-type turbine, synchronous generator and associated switchgear and controls (Figure 14). A new route beginning at the downstream end of Lower Trail Lake and continuing around the east side ofVagt Lake would split to provide access to the powerhouse and the intake sites (Figure 14). An overhead transmission line would connect directly to the existing transmission line along the Seward Highway. Detailed parameters for Alternative I are shown in Table 5.

    Alternative 2: Impoundment

    This alternative would provide active storage (see Active Storage, above) by creating a small impoundment of Grant Lake. Key features would include a 9-foot-high concrete gravity structure located at the outlet of Grant Lake. An intake and sluiceway would be constructed integral to the structure. The remaining project features would be the same as in Alternative I (for detailed parameters, see Table 5).

    Alternative 3: Impoundment + Drawdown

    Alternative 3 would enhance Alternative 2 by providing additional active storage through drawdown of Grant Lake below its naturally occurring minimum elevation. Drawdown would be made possible by extending a pipeline into the lake and installing vacuum pump equipment. At low lake levels the intake would act as a siphon allowing the lake to be drawn down to an elevation of 675 ft. Detailed parameters for Alternative 3 are shown in Table 5.

    Alternative 4: Ebasco's 1984 Preferred Project

    Alternative 4 was the preferred project identified by Ebasco (APA 1984; Alternative D), and would consist of a lake tap in Grant Lake, a tunnel from Grant Lake to the powerhouse on Upper Trail Lake and a powerhouse located on Upper Trail Lake. Detailed parameters for Alternative 4 are shown in Table 5.

    13

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance Wor'i>J't

    Alternative 5: Impoundment + Drawdown + Falls Creek

    Earlier evaluations identified the possibility of increasing flows in Grant Creek by diverting nearby Falls Creek. Alternative 4 would combine the features of Alternative 3 with the diversion of Falls Creek in order to augment flows available for hydroelectric generation. Detailed parameters for Alternative 5 are shown in Table 5.

    Summary of Alternatives

    Table 6 summarizes the key parameters of alternatives that were evaluated. Maximum headwater for alternatives that would not include storage would be lower for Alternatives 1 and 4 (691 ft, natural elevation of Grant Lake). For alternatives that would feature storage, the maximum headwater would be located at an elevation of 700 ft. Minimum headwater would be lower in alternatives that would feature drawdown (Alternatives 3 and 5, both 675 ft) or a lake tap (Alternative 4, 660 ft). Projects including no drawdown would have a minimum headwater at 691 ft, Grant Lake's natural elevation. All alternatives would include a tail water elevation of 530 ft (powerhouse located alongside Grant Creek), except the alternative that would employ a lake tap and powerhouse on Trail Lake (470 ft). Alternative 4, with a powerhouse at Trail Lake, would utilize the greatest net head (206 ft); net head for alternatives with a powerhouse along Grant Creek would range from 145 ft (Alternative I) to 154 ft (Alternatives 2,3 and 5; Table 6), depending on drawdown and storage.

    Design flow was 430 cfs (see Turbine Sizing, below) for all alternatives except Alternative 4 (lake tap to Trail Lake), designed for 460 cfs (Table 6). It follows that all alternatives would have a capacity of 4.7 MW, except Alternative 4 which could generate 7.0 MW because of its higher head and flows. All alternatives would use an average inflow of 193 cfs, except for Alternative 5, which would utilize an average inflow for 222 cfs (with addition of flows from Falls Creek). Alternative 1 provides no storage, as would operate in run-of-the-river mode. Alternatives 2, 3 and 5 include 38,500 AF of active storage. Alternative 4 provides the most storage, at 48,000 AF (Table 6).

    Turbine Sizing

    F or Alternative 1, the rated flow of the turbine was sized at 15% on the flow duration curve, or 430 cfs. A sensitivity analysis indicated that design flows within 10% of this assumption yield near identical energy generation estimates12. This assumption is appropriate for reconnaissance-level study. Alternatives utilizing storage (Alternatives 2 through 5) produced similar results; in order to simplify evaluation of competing alternatives; the design flow was kept constant.

    12 For comparison purposes, APA (1984) concluded that the energy from their preferred alternative was nearly constant over flows ranging from 390-531 cfs (Ref. Table 17-3 of APA 1984).

    14

  • Other Alternatives Evaluated

    Grant Lake ~ Proposed Hydroelectric Project Reconnaissance 1

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance Report

    For daily simulations, head loss was calculated using the daily flow. For monthly simulations, the project was assumed to operate at the best gate position, corresponding to a 7.5% head loss.

    All available flow was used for energy production. No minimum instream flow was released in the bypass reach of Grant Creek. The tailwater of the powerhouse was placed at 530 ft elevation to reintroduce water into Grant Creek above the most productive fish habitat.

    Objective Function

    When the prices for energy (or other benefits of generation) are not constant throughout the year due to seasonal variations, it may be desirable to dispatch the project to maximize revenue instead of energy. To model this situation, seasonal variations in energy values were weighted as shown in Table 7.

    [n this reconnaissance-level report, the effect of maximizing energy based upon seasonal incentive is referred to as the "seasonal benefit" (See Energy Calculations, Appendix B, for more detail). Figure 15 illustrates this concept for Alternative 3 (impoundment and drawdown) during an average water year. In this instance weighting the months shifts the generation to the high value months of December and January. Overall energy generation actually decreased by 1.7% due to lower headwater elevations but total revenue increased by 6.1 % (Figure 15) by generating more in more valuable months.

    Results

    Table 8 presents the results of the reconnaissance level energy generation estimates for the various alternatives. Alternatives featuring storage (Alternatives 2 through 5) would produce more energy annually (19.0-25.4 GWh) than a run-of-the-river project (Alternative 1; 13.7 GWh). Plant factor, the ratio of average power load to its rated capacity, was lower for the run-of-the-river project (Alternative 1; 0.33) than for projects featuring storage (Alternatives 2 through 5; 0.42-0.51), due to the lower rated capacity of the run-of-the-river project. Seasonal benefit ranged from 2.7-6.1 % for alternatives with storage, owing to the fact that stored water could be used to produce energy in winter. A run-of-the-river project would not take advantage of storage and thus would have no associated seasonal benefit (Table 8).

    Cost Estimates

    Opinions of probable construction costs were derived for each of the alternatives presented above. Cost information detail is included in Appendix C. We assumed most alternatives would make use of many of the same construction features. At this level of study, variances in alternative project costs can be directly attributed to the type of intake and impoundment.

    The approach used was to develop base work units and unit prices and then apply these units and prices consistently to the various alternatives. This approach allowed a common platform from which to quickly establish priority amongst the alternatives, although slight differences do exist. It should also be noted that the project sizes for the various alternatives may not be the true

    16

    http:0.42-0.51

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance """"Irl

    optimum. For example, future refinement may determine that the design flow for the turbine should be slightly greater or smaller than what was assumed. A sensitivity analysis performed as part of the energy generation estimating process indicated assumed values were appropriate.

    Although future refinement of the estimated unit costs or generation estimates may affect the final benefit/cost evaluation, it should not affect the ranking of the alternatives amongst themselves.

    The following assumptions were used in the cost estimate:

    Indirect construction costs associated with engineering, construction management, licensing, permitting and the owner's internal costs were added to the direct construction cost estimate as either percentages or lump sum amounts.

    Design engineering was assumed to be 10% of the total direct construction costs.

    A lump sum value of $1,000,000 was assumed to provide environmental baseline studies in support of the FERC licensing application. As well as preparation for the FERC licensing application.

    The Owner's General Administration and Overhead of the design and construction was assumed to be 5% of the total direct construction costs.

    Construction management was assumed to be 5% of the total direct construction costs.

    A contingency of 30% was added to the total of the direct and indirect construction costs to reflect uncertainties of layout and design that wouldn't be resolved until later in the development process.

    Interest accrued during a 3-year construction period was assumed to be 7% and was added to the total of the direct and indirect construction costs.

    The estimate assumed first-year operations and maintenance (O&M) expense were comprised of the following three expenses

    o Total labor, expenses and owner's general and administrative (G&A) expenses were estimated at $300,000/yr13

    o A repair and replacement fund of $50,000 was also included.

    o General liability and business interruption insurance was estimated at $1.00 per $100.00 of asset.

    13 The estimated G&A expense could be reduced if several of the sites investigated are constructed which would allow some economies to be realized between the similar operations of the hydroelectric projects.

    17

  • Grant Lake Proposed Hydroelectric Project Reconnaissance Report

    Cost estimates assumed that the project would be designed for un-manned operations and would be part of a larger organization; thereby the project would experience lower administrative expenses. On-site O&M labor would be limited to periodic inspections and seasonal maintenance.

    Results

    Table 9 presents the results of the reconnaissance level cost estimates for the five alternatives considered. It should be noted that the costs in Table 9 are relative and not absolute. A run-of-the-river project (Alternative 1) would have the lowest estimated project cost of $24.0 M. Estimated project cost of Alternatives 2 and 3 was similar at $25.3 and $26.3 M, respectively. Alternatives 1 through 3 would all provide the same 4.7 MW capacity for energy generation. Estimated project cost for Alternative 4 ($52.2M) was more than twice that of Alternatives I through 3, but this project would have a greater capacity of 7.0 MW. Alternative 5 would have the same capacity as Alternatives 1 through 3, but this project would have a greater estimated project cost of $39.8 M (Table 9).

    For comparison, according to the Bureau of Labor and Statistics, consumer prices have risen 217% since 1983. Using this statistic, the preferred alternative identified in the APA (1984; Alternative 4 in this report) would have a current price of approximately $55M.

    Economic Evaluation and Alternative Ranking

    A detailed economic evaluation was not included in the scope of this work. However, in order to provide a conceptual view of the economics and to provide a means of ranking the alternatives, we have made some generic financial assumptions. We have chosen to present the results as estimated annual cost per kilowatt-hour (kWh) in 2008 dollars. In deriving these costs, we assumed that the project could be financed through the issuance of bonds. Our assumption was that 100% of the debt would be financed at 6% for 30 years.

    Results of the economic evaluation and alternative ranking analysis are shown in Table 10. A sensitivity analysis of the key assumptions showed the relative ranking of the alternatives unchanged by reasonable variation in unit prices and quantities, providing verification of the estimating approach outlined above. It should be noted that the costs in Table 10 are relative and not absolute.

    A complete analysis of cost of each of the alternatives requires not only consideration of the financial parameters but also an integration of environmental and licensing considerations. These latter concerns are not nearly as tangible as estimating costs and energy, so their impact on cost is subjective at this point. Based upon past experience, we have integrated them as fairly as possible into the ranking (Table 10).

    Conclusions and Recommendations

    Based upon the results of this reconnaissance level study, development of a project at the outlet to Grant Lake with storage between 10,000-40,000 acre-feet appears to be the most feasible. Storage levels below this minimum reduce the ability to capture and release high flows. Storage

    18

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance

    levels above this maximum must bear the cost of deepening the channel at mid lake without a commensurate increase in energy production. The main benefit of increased storage within this target range is the ability to potentially shift generation to higher valued months.

    It is recommended that Alternatives 2 (impoundment) and 3 (impoundment and drawdown), be studied at a feasibility level in order to better identify project features and costs.

    19

  • References

    Grant Lake Proposed Hydroelectric Project Reconnaissance Report

    Alaska Department of Natural Resources (DNR). 1998. Kenai River Comprehensive Management Plan. Rep. from Division of Land and Division of Parks and Outdoor Recreation in conjunction with Alaska Department of Fish and Game, Habitat and Restoration Division, and Kenai Peninsula Borough. Anchorage, Alaska.

    Alaska Power Authority (APA). 1984. Grant Lake Hydroelectric Project Detailed Feasibility Analysis. Volume 2. Environmental Report. Rep. from Ebasco Services Incorporated, Bellevue, Washington.

    Arctic Environmental Information and Data Center (AEIDC). 1982. Preliminary summary of environmental knowledge of the proposed Grant Lake hydroelectric project area. Interim report submitted to Ebasco Services, Inc., Redmond, Washington, University of Alaska, Anchorage, Alaska.

    Arctic Environmental Information and Data Center (AEIDC). 1983 Summary of environmental knowledge of the proposed Grant Lake hydroelectric project area. Final Report submitted to Ebasco Services, Inc., Redmond, Washington, University of Alaska, Anchorage, Alaska.

    Boggs, K., J. C. Davis, A.A. Milner. January 1997. Aquatic and Terrestrial Resources of the Kenai River Watershed: A Synthesis of Publications. Alaska Natural Heritage Program for the Environmental Protection Agency, 1997, EPA 91O/R-97-001.

    Buchanan, T.1., and Somers, W.P. 1969. Discharge measurements at gauging stations. In Chapter A8, Book 3, Techniques of water resources investigations of the United States Geological Survey.

    CH2M Hill. 1980. Feasibility assessment hydropower development at Grant Lake. City of Seward, AK.

    Dudiak, N. 1980. Environmental assessment, Trail Lakes Hatchery, Kenai Peninsula, Alaska. Submitted to U.S. Forest Service, Chugach National Forest by Alaska Dept of Fish and Game, Fisheries Rehabilitation, Enhancement and Development Division, Anchorage, Alaska. 1980

    Johnson, J. and M. Daigneault. 2008. Catalog of waters important for spawning, rearing, or migration of anadromous fishes Southcentral Region, Effective June 2, 2008. Alaska Department of Fish and Game, Special Publication No. 08-05, Anchorage, Alaska.

    Kenai Peninsula Borough (KPB). 2008. Coastal management plan. Effective June 2008.

    Meade, 1. 2006. Draft environmental impact statement: Kenai winter access. United States Department of Agriculture, Forest Service, Alaska Region, Chugach National Forest. Anchorage, Alaska

    20

  • Grant Lake Proposed Hydroelectric Project Reconnaissance wnr'''' .. '

    Plafker, G. 1955. Geologic investigations of proposed power sites at Cooper, Grant, Ptarmigan, and Crescent Lakes, AK. U.S. Geological Survey Bulletin 1031-A. U.S. Government Printing Office, Washington D.C.

    Quilliam, R. 1982. Personal communication. 1982. Resource Assistant, U.S. Department of Agriculture, Forest Service, Chugach National Forest, Seward, AK.

    R. W. Beck and Associates. 1982. Kenai Peninsula power supply and transmission study supplement.

    U.S. Army Corps of Engineers (USACE). 1981. National Hydroelectric Power Study, Regional Report. Regional Report: Volume XXIII - Alaska. USACE North Pacific Division, Portland, Oregon and Alaska District, Anchorage, Alaska.

    U.S. Fish and Wildlife Service (USFWS). 1961. Ptarmigan and Grant Lakes and Falls Creek, Kenai Peninsula, Alaska, progress report on the fish and wildlife resources. Department of the Interior. Juneau, Alaska.

    U.S. Geological Survey (USGS). 1981. Surface water quality records, Southcentral Alaska, 1949-1974. Unpublished computer printout.

    21

  • Tables

    22

  • Grant Lake - Proposed Hydroelectric Project

    Table 1. Falls Creek scale factors (determined by APA 1984) used to simulate flow of Falls Creek from stream flow data collected at Grant Creek.

    Month Scale factor

    October 6.2%

    November 0

    December 0

    January 0

    February 0

    March 0

    April 0

    May 5.2%

    June 24.2%

    July 21.2%

    August 14.6%

    September 13.4%

    23

    Reconnaissance - Tables

  • Grant Lake - Proposed Hydroelectric Project Reconnaissance - Tables

    Table 2. Temperature comparisons for Grant Lake, Grant Creek and Falls Creek. Adapted from Table 2-8 in APA (1984).

    Values for Grant Lake were surface temperatures.

    Temperature Difference Temperature between difference

    Falls Grant Lake between Grant Grant Cr. and Grant Cr Grant Cr.

    Date Source Lake (OF} Cr. {OF} {OF} {OF} and Falls Cr.

    111311959 USFWS (1961) 39.9 32.5

    6/8/1960 " " 46.0 41.0 611711960 " "