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JF N-e TASK 5 Appendix EKLUTNA LAKE ALTE NATIV E WATER so ul- E EVALUATION Eagle River Water Resource Study Municipality of Anchorage Water and Sewer Utilities 0,0 0001t FtC CH2MnmnmHlLL December 1981 I ID TASK 5 Appendix EKLUTNA LAKE ALTERNATIVE WATER SOURCE EVALUATION Eagle River Water Resource Study Municipality of Anchorage Water and Sewer Utilities US Derartment of commerce 110AA P@ervlces Center LibrarY Hobson Avenu e -@@ston., 13C 29405-2413 CH2MI110HILL December 1981 Cover photo by: Air Photo Tech, Inc. OF A4Cq@%% 49th -70767 - 4092--E This report was prepared under the supervision of a registered professional engineer. The preparation of this report was financed in part by funds from the Office of Coastal Zone Management, National Oceanic and Atmospheric Administration, U.S. Department of Commerce, admin- istered by the Division of Community Planning, Alaska Department of Community and Regional Affairs. K 13765. GO PREFACE To pursue the recommendations for further study that were pre- scribed in the Metropolitan Anchora2e Urban Study, completed by the U.S. Corps of Engineers in 1979, _tFe_7Wu_n'Tc@ipa ity of Anchor- age engaged CH2M HILL to conduct the Eagle River Water Re- source Study. The purpose of the study is to investigate the potential sources of water supply from the Eagle River Valley. The original scope of the study comprised of four tasks: Task 1 Well Drilling Program Task 2 Preliminary Damsite Investigation Task 3 Flour Water Treatment Study Task 4 Transmission Main Design Task 5, Eklutna Lake Alternative Water Source Evaluation, was added to the scope of this project after the completion of the first four tasks. The report for each task is bound separately and is an appendix to the summary of the entire study. This Appendix V is the report for Task 5. on NO ACKNOWLEDGMENTS We wish to express our appreciation to the following people: � The Anchorage Water and Sewer Utilities staff for their contributions at the weekly meetings, updating of task scopes, and overall administrative assistance � The U.S. Department of Energy, Alaska Power Admin- istration, personnel for their valuable assistance, partic- ularly in making available the reports and unpublished data on the Eklutna hydroelectric project, and for their cooperation during our field work v SUMMARY AND CONCLUSIONS The purpose of the Eagle River Water Resource Study was to investigate the potential of the Eagle River Valley to provide 70 million gallons per day (mgd) of water to meet the metropolitan Anchorage area's increasing demands. Expansion 'of existing sources and development of new sources within the Anchorage Bowl are also needed to help meet these demands. The results of the four tasks of the study indicated that the only possible source from the Eagle River Valley would be surface water impounded by a dam and reservoir on the Eagle River. A fifth task was added to identify one or more alternative water supply projects on or near Eklutna Lake, to screen these alterna- tives, to compare them with the proposed Eagle River dam and reservoir project (Appendix 11, Preliminary Damsite Investiga- tion), and to make recommendations. Eklutna Lake is a high-altitude glacially formed lake 30 miles northeast of downtown Anchorage and 16 miles northeast of the Eagle River. The annual inflow to Eklutna Lake averages over 200 mgd and the average elevation of the lake is above 845 feet. Essentially all of this flow and head is used by the Eklutna hydroelectric project, which began operation in 1955. Prior to the development of the project, the lake waters flowed down the 10-mile-long Eklutna River to the Knik Arm of Cook Inlet. Any water supply project drawing on Eklutna Lake must take into consideration this 30-MW project, which generates an average of 155 kWh per year. Diversion of Eklutna Lake water upstream of the turbines would reduce the hydroelectric energy output. Any municipal water supply project that diverts the water below the turbines would require large amounts of pumping energy because the tailrace water is near sea level. The hydroelectric project has several key elements that were con- sidered in identifying alternative water diversion points in this report: a 9-foot-d ia meter, 4-1/2-mile-long concrete-lined tunnel; a tailrace channel near sea level; and a dam with a 30-inch by 30-inch gate at elevation 852 feet and an uncontrolled spillway at elevation 871 feet. There is also a 1,395-foot penstock between the tunnel and the power plant. However, it was not considered in any of the supply development alternatives because tapping the penstock could seriously affect downstream hydraulics. ALTERNATIVES Three conceptual project alternatives were developed using var- ious points of diversion, treatment plant locations, pump stations, and pipeline routes. All the pipeline routes that were considered vii would join the proposed pipeline (Appendix IV, Transmission Main Design) from the Eagle River to the existing Municipal Water Treatment Plant near Ship Creek. The Eklutna alternatives would require about 22 more miles of pipeline than would the Eagle River diversion. The Eklutna River watershed below Eklutna Lake was considered as a supplemental water source in developing these alternatives. This would reduce the project impact on the exist- ing hydroelectric facility or reduce pumping energy requirements, depending on which alternative configuration were used. Each alternative could meet the projected demand of the Anchorage area that cannot be met by local sources. However, the sources within the Anchorage Bowl would have to be developed in order to meet intermediate or peak demands. Alternative 1: Tailrace and River Diversion This alternative draws water from the hydroelectric project tail- race and from the Eklutna River at a point near the Old Glenn Highway bridge. Early in-the life of the project, a large per- centage of the summer demand would be provided by the river flows. Later, as demands increased and during periods of low flow in the river, more water would be pumped from the tailrace. Tailrace and river water would be treated near the village of Eklutna and pumped to Anchorage through a 54- to 48-inch pipe- line. Treated water would be available to communities along the line. Alternative 2: Tunnel Diversion In this alternative, water would be diverted from the pressurized hydroelectric tunnel at the adit near the surge tank. This would divert water upstream of the turbines. All of the ultimate 70-mgd demand would be provided from this location. The water would be treated at a high-altitude treatment plant and would flow by gravity to Anchorage through a 60- to 48-inch pipeline. Commun- ities along the pipeline would take water through pressure- reducing valves. Alternative 3: Eklutna Lake and River Diversion This alternative would take water directly from Eklutna Lake and the Eklutna River. Except for the Eklutna Lake dam, none of the existing hydroelectric project facilities would be affected. Early in the life of the project, a large percentage of the increasing demand would be provided by the river flows. Much of the winter low flows in the river would be required for minimum streamflow maintenance downstream of the diversion structure near the Old Glenn Highway. To meet demands not met by the river, water would be diverted into the river by opening the 30-inch by 30-inch gate in the existing Eklutna Lake dam. When the lake level is too low, the lake water would be pumped to the gate by a low-head pump station. The lake water would flow viii down the river'to the diversion structure near Old Glenn High- way. The lake and river water would be treated near the village of Eklutna and pumped to Anchorage through a 54- to 48-inch pipeline. Treated water would be available to communities along the pipeline. As demand approaches 70 mgd, more lake water would be diverted, which decreases the amount of water available for power generation. COMPARISON OF EKLUTNA ALTERNATIVES WITH THE EAGLE RIVER PROJECT Water Treatment The water quality of Eklutna Lake is similar to that of the Eagle River, though less turbid. Bench-scale testing indicates that treatment processes, as for the Eagle River water, would consist of flocculation with alum, sedimentation, filtration, and disinfec- tion. These processes should make Eklutna Lake water an excel- lent source of potable water. A year of treatment pilot plant test- ing, at a 1-mgd minimum, should be conducted to verify the ade- quacy and effectiveness of the selected treatment systems. Energy Impacts The energy impacts of the Eklutna alternatives and of the Eagle River dam and reservoir project are shown in the following table. ANNUAL ENERGY AND CAPACITY IMPACTSa Eklutna Alternative Eagle 1 1 3 River Total Energy Impact (MWh) 14 mgd 11,869 12,150 15,671 6,850 45 mgd 49,496 43,900 68,945 23,400 70 mgd 88,003 67,737 121,680 38,808 Total Capacity Impact (kW) 14 mgd 1,500 150 1,490 1,150 45 mgd 6,500 Soo 5,720 3,500 70 mgd 12,025 775 10,005 6,175 Annual Cost of Impacts (x $1,000) 14 mgd 1,136 1,056 1,464 676 45 mgd 4,754 3,838 6,383 2,278 70 mgd 8,486 5,922 11,257 3,221 aWithout additional sources developed in the Anchorage Bowl, 14 mgd is needed by 1985, 45 mgd is needed by 2000, and 70 mgd is needed by the year 2012. (Metropolitan Anchorage Urban Study, Volume 2, Water Supply. U.S. Army CoFp-s of Engin e-rs-.--T979.) D e-v-elo -pm e-n t of-A-ncTFo_rage Bowl water sources will delay the need for these volumes of water from a source outside of the Anchorage Bowl. ix These impacts include the replacement energy for lost hydroelec- tric generation, energy for pumping and treatment, and capacity to provide the needed energy. The tunnel diversion, Alterna- tive 2, requires much less energy than the other alternatives, but uses much more than the Eagle River project. The cost of pumping and replacement energy is assumed to be 8.661 per kWh, the expected cost (1981 dollars) of new thermal generation. Costs The capital costs for the four projects (1981 dollars) are: Alternative 1 (Tailrace and River): $149 million Alternative 2 (Tunnel Tap): $151 million Alternative 3 (Lake and River): $131 million Eagle River Dam and Reservoir: $122 million The Eagle River project costs are not complete nor directly com- parable to the costs of the Eklutna alternatives. Substantial cap- ital cost items that have not yet been determined for the Eagle River project are reservoir land acquisition, old Eagle River dump water quality impact mitigation, fish facilities and habitat impact mitigation, and other special environmental considerations. These costs could range over many millions of dollars. In addition, cer- tain features of the Eagle River project were analyzed in more detail than the Eklutna alternatives. Therefore, confidence limits for the Eklutna project cost estimates are broader than for the Eagle River project. The following table compares annual project costs for the least costly Eklutna alternative (Alternative 2) with those for the Eagle River project. It can be seen that total annual costs are quite comparable. TOTAL ANNUAL COST FOR CAPITAL, OPERATION AND MAINTENANCE (1981 DOLLARS) 1985 2012 Project (13. 5 m9d) (70 m9d) Eklutna Alternative 2 Minus 20% Confidence Limit $11 million $16 million Plus 20% Confidence Limit 17 million 25 million Eagle River Dam and Reservoir Minus Undetermined Items 11 million 16 million Plus $30 Million Capital Cost for Undetermined Items 14 million 18 million x Environmental The principal environmental concerns for the Eklutna alternatives a re: 0 The management of the pipeline right-of-way 0 Loss of wildlife habitat 0 Fishery impacts (in the lower Eklutna River) 0 Water quality effects of human activity 0 Recreational use of watershed 0 Operation of a thermal power plant for replacement or pumping energy production The environmental concerns relating to natural resources are less for the three Eklutna alternatives than for a dam and reservoir at Eagle River. Potential fisheries impacts are less, and potential impacts on wildlife are much less. While there might be slightly greater fisheries impacts from Eklutna Alternatives 1 and 3 than from Alternative 2, they are not expected to be large. The impacts on water quality and the potential effects of water quality on human health are much less with the Eklutna options than with Eagle River, particularly in regard to sediment and sludge disposal. The old Eagle River dump also poses potential water quality problems for the Eagle River dam project. Visual impacts are not a problem at Eklutna compared with the impacts of the proposed reservoir on the Eagle River. Projects in either watershed would encourage development in the Eagle River- Eklutna area because they would provide water to this area. The Eklutna alternatives would require less right-of-way and land acquisition than the Eagle River project. Eklutna Alternative 3 requires a shorter pipeline than Alternatives 1 and 2. CONCLUSIONS AND RECOMMENDATIONS The costs for both the Eagle River project and the Eklutna alter- natives would probably be comparable with the addition of the undetermined capital costs to the Eagle River project costs, but the development of a water supply project at Eklutna would have considerably less environmental impact. Potential delays of the Eagle River project for land acquisition, environmental studies, and old Eagle River dump mitigation lead to the conclusion that construction of the Eklutna project can begin sooner. Addition- ally, inflation effects of such delays could severely raise final construction costs of the Eagle River project. All three Eklutna alternatives appear feasible, and none incurs cost, scheduling, construction, and environmental problems of the magnitude that the Eagle River dam and reservoir project must add ress. Alternative 1, tailrace and river diversion, would incur xi energy costs for pumping; however, it does not significantly im- pact the operation of the Eklutna hydroelectric project, whose energy losses would have to be reconciled. Further, it could be implemented sooner than the other alternatives. It is recom- mended, therefore, that Eklutna Alternative 1 be pursued as part of the solution to the Municipality of Anchorage's projected water needs through the year 2025. xii CONTENTS Page Preface iii Acknowledgments v Summary and Conclusions vii 1 Introduction 1-1 Background 1-1 Purpose and Scope 1-4 Site Description 1-6 Limitations 1-6 2 Eklutna Watershed 2-1 Description 2-1 Climate 2-2 Hydrology 2-2 Lake Ice 2-9 Sedimentation 2-10 Lake Evaporation 2-12 3 Existing Eklutna Lake Hydroelectric Facility 3-1 History 3-1 Existing Facilities 3-1 Energy Output 3-10 4 Supply Alternatives 4-1 Possible Diversion Sites 4-1 Assumptions and Criteria 4-4 Alternative 1: Tailrace and River Diversion 4-7 Alternative 2: Tunnel Diversion 4-9 Alternative 3: Eklutna Lake and River Diversion 4-10 Further Considerations 4-12 5 Water Quality and Treatability 5-1 Data Collection and Evaluation 5-1 Treatment Requirements and Design Considerations 5-9 Cost Estimates 5-19 Summary and Conclusions 5-20 6 Energy Impact and Cost Analyses 6-1 Background 6-1 Reservoir Operations 6-1 Energy Lost By Diversion of Water Upstream of Turbines 6-4 Energy Required for Pumping 6-5 Energy Required for the Treatment Plant 6-8 Effect on South-Central Alaska Power and 6-8 Energy Supply xiii Paqe Cost of Replacing Energy Lost to the Electric Systems 6-9 Capital Costs 6-9 Summary 6-19 7 Environmental Considerations 7-1 identification of Environmental Concerns 7-1 Environmental Concerns 7-2 Comparison of Diversion Alternatives 7-3 Comparison of Environmental Effects of the Eagle River Diversion and Eklutna Alternatives 7-5 Summary 7-5 8 Conclusions and Recommendations 8-1 Recommendations 8-4 9 Bibliography 9-1 Exhibit A. Transmission Pipeline Criteria Exhibit B. USGS Water Quality Data xiv TABLES Paqe 2-1 Inflow to Eklutna Lake 2-6 2-2 Outflow of Eklutna Lake 2-7 2-3 Eklutna Lake Water Surface Levels 2-8 2-4 Anchorage Light and Power Dam Inflow Less Eklutna Lake Outflow 2-8 3-1 Eklutna Gross Generation 3-10 5-1 Comparison of Eagle River and Various Eklutna Water Qualities 5-3 5-2 Field Test Quality Results 5-5 5-3 Laboratory Test Quality Results 5-6 5-4 Water Quality Standards and Eklutna Lake Quality 5-11 5-5 Estimated Project Costs 5-19 5-6 Annual Operation and Maintenance Costs 5-28 6-1 Eklutna Hydroelectric Energy Reduction Summary 6-5 6-2 Power Supply Impact of Alternative Diversions of Eklutna Water and Eagle River 1 6-6 6-3 Cost of Future Energy and Capacity Incurred by Diversion of Eklutna and Eagle River Water to Anchorage 6-10 6-4 Order-of-Magnitude Cost Estimate for Alternative 1 6-12 6-5 Order-of-Magnitude Cost Estimate for Alternative 2 6-13 6-6 Order-of-Magnitude Cost Estimate for Alternative 3 6-14 6-7 Order-of-Magnitude Cost Estimate for Eagle River Water Supply Dam and Pipeline 6-15 6-8 Annual Cost Summary Eklutna Alternatives and Eagle River Project 6-18 7-1 Magnitude of Environmental Effects, Eagle River Project and Eklutna Alternatives 7-6 xv FIGURES Page 1-1 Vicinity Map 1-2 1-2 Projected Water Demand Increase, 1980-2025 1-3 2-1 Eklutna Drainage Areas 2-3 2-2 Eklutna River - Thunderbird Creek Watershed, Available Monthly Flow 2-11 3-1 Eklutna Project Features, Schematic Plan and Profile 3-2 3-2 Spillway of New Dam, General Plan and Sections 3-4 3-3 New Dam Spillway Flood Routing Curves 3-5 3-4 Pressure Tunnel, Sections and Detail; Station 20+00 to 255+10 3-6 3-5 Pressure Tunnel Adit, Closure Details 3-8 3-6 Eklutna Hydroelectric Project Location Map 3-9 4-1 Annual Water Diversion From Proposed Water Sources 4-19 4-2 Alternatives 1, 2, and 3 Layout 4-21 4-3 Alternative 1, Tailrace and River Diversion Plan and Profile, Station 600+00 to 1215+00 4-23 4-4 Alternative 1, Tailrace and River Diversion Plan and Profile, Station 1215+00 to 1770+00 4-25 4-5 Tailrace Intake Structure and Pump Station, Site Plan 4-27 4-6 Tailrace Pump Station, Plan and Section 4-28 4-7 Tailrace Pump Station, Annual Energy and Maximum Power Requirements 4-29 4-8 Eklutna River Water Treatment Plant Pump Station, Annual Energy and Maximum Power Requirements 4-30 4-9 Mirror Lake Booster Pump Station, Plan View 4-31 4-10 Mirror Lake Booster Pump Station, Annual Energy and Maximum Power Requirements 4-32 xvii 4-11 Alternative 1, Total Annual Energy and Maximum Power Requirements (Excluding Water Treatment Plant) 4-33 4-12 Alternative 2, Tunnel Diversion, Plan and Profile, Station 600+00 to 1215+00 4-35 4-13 Alternative 2, Tunnel Diversion, Plan and Profile, Station 1215+00 to 1900+00 4-37 4-14 Alternative 3, Eklutna Lake and River Diversion, Plan and Profile, Station 600+00 to 1215+00 4-39 4-15 Alternative 3, Eklutna Lake and River Diversion, Plan and Profile, Station 1215+00 to 1365+00 4-41 4-16 Alternative 3, Eklutna Lake and River Diversion, Plan 4-43 4-17 Eklutna Lake Diversion, Site Plan 4-45 4-18 Eklutna Lake Pump Station, Annual Energy and Maximum Power Requirements 4-46 4-19 Alternative 3, Total Annual Energy and Maximum Power Requirements (Excluding Water Treatment Plant) 4-47 5-1 USGS Water Sampling Points 5-2 5-2 Coagulation of Water With High Turbidity 5-8 5-3 Settled Water Turbidity versus Alum Dosage 5-8 5-4 Settled Water Turbidity versus Settling Time for Various Mixed Speeds 5-10 5-5 Treatment Process Options 5-13 5-6 Typical Plant Flow Schematic 5-15 5-7 Preliminary Plant Layout 5-16 6-1 Eklutna Lake Levels Since 1965 6-2 6-2 Eklutna Alternative and Eagle River Dam and Reservoir, Estimated Annual Impacts on Energy Production 6-7 6-3 Eklutna Alternative and Eagle River Dam and Reservoir, Annual Cost of Energy and Capacity Requirements 6-11 xviii 6-4 Eklutna Alternatives, Total Annual Costs 6-16 6-5 Eklutna Alternative 2 versus Eagle River Dam and Reservoir, Total Annual Cost 6-17 8-1 Comparison of Water Supply Alternatives 8-2 xix Chapter 1 INTRODUCTION BACKGROUND The population and, thus, the water supply needs of the metro- politan Anchorage area are rapidly growing. Presently, water to Anchorage is principally supplied by surface water from Ship Creek and by groundwater wells in the Anchorage Bowl. How- ever, if present growth trends continue, these sources will not meet future needs. In 1974 the United States Congress authorized the U.S. Army Corps of Engineers to perform the Metropolitan Anchorage Urban Study (MAUS), which was completed in 197T. e purpo-si-e-37 VAUS was "to evaluate the adequacy of the developed water sup- ply in the metropolitan Anchorage area, to determine future water demands, to assess sources for water supply development, and to formulate water supply plans to meet the increased future de- mand" (U.S. Army Corps of Engineers, 1979). The MAUS study area comprised the Anchorage Bowl and the area northeast to the town of Eklutna (Figure 1-1). The projected future water demand increases, determined in the MAUS, are shown in Figure 1-2. It is expected that by the year 2025 an additional 81.5 million gallons per day (mgd) of water will be needed to meet the increased demands in the area. The MAUS report identified many potential sources of supply: Eagle River Valley groundwater; Anchorage Bowl groundwater; and surface water from Campbell Creek, Ship Creek, Eagle River, and Eklutna Lake. Two plans were recommended by MAUS for future study. Plan IV, which ranked first environmentally and socially, included a combination of supply from Ship Creek, An- chorage Bowl groundwater, and Eklutna Lake. Plan VI, which ranked first on an economic basis, included an increased supply from Ship Creek, winter diversion from Eagle River, further development of Anchorage Bowl groundwater, and exploration for Eagle River Valley groundwater. To increase the existing water supply sources within the Anchor- age Bowl, the Municipality recently constructed a 36-inch supply main to its water treatment plant from the military diversion facil- ity on Ship Creek. Other developments are expected to include new wells to increase groundwater supply and expansion of the Municipal Water Treatment Plant facilities. However, rapidly growing demands in Anchorage require development of a new source outside the Anchorage Bowl within the next 10 years. Demands in the Eagle River-Chugiak-Eklutna area, northeast of Anchorage, require development of a new source now. 1-1 0 0,0 04@i;, 0 0 D 0 '74@9. C, S.. KIN) L AC %A P EkL' A L EKLU N 00 G )@FQWE L oo A4 JM ,3 -0*--@TU 4EL 'JBIR6@0' PETERS CREEK HIVE EKLUTNA CHLIGIAK 0 0 LAKE 0 P m 01 TOWN OF EAGLE RIVER-------'-,, RR MPGROUNb ".. BRIDGE ...... FORT RICHARDSON LMENDORF EAGLE RIVER 1@@IR FORCE BASE VALLEY EKLUTNA ANCHORAGE RI GLACIER CHUGACH MOUNTAINS EAG E GLACIER 0 Miles 5 Figure 1-1 Vicinity Map 1-2 0 c WATER DEMAND INCREASE (mgd) @n CD z 1980 0 m A m 12. 1985 CD 1990 CD CL 0 1995 0 m 2000 3 2005 - 2010 - r (D R 2015 - IM 0 CD U) 00 (D M -L CL 2020 - co * Go 0 lb P6 ;; 2025 - CIL As a result of the MAUS findings, the Municipality decided to investigate potential sources outside the Anchorage Bowl that could supply 70 mgd of water. Based on the MAUS population projection, this diversion would satisfy the demands of the entire study area through the year 2012. The increases in water supply capacity that are expected to be developed within the Anchorage Bowl will delay the need for the full 70-mgd capacity of the new water source outside the Bowl until approximately the year 2020 or longer. To investigate possible sources of water supply outside the An- chorage Bowl, the Municipality engaged CH2M HILL to conduct the Eagle River Water Resource Study. This original scope of the study comprised four separate tasks to investigate the Eagle River Valley (Figure 1-1) as a potential source of municipal and indus- trial water supply: 0 Task 1, a well drilling program to study the feasibility of developing the Eagle River Valley as a groundwater source 0 Task 2, a preliminary damsite investigation to determine the feasibility of developing the Eagle River as a sur- face water source 0 Task 3 was a study to determine if glacial rock flour in the Eagle River water could be easily removed 0 Task 4, a preliminary design of a pipeline to transport groundwater or surface water from the Eagle River Val- ley to Anchorage Each task was conducted independently. The results of the first four tasks clearly indicate that a substan- tial dam and reservoir are required to develop the Eagle River as a water source. Before committing itself to this dam and reser- voir project, the Municipality of Anchorage increased the study scope to include Task 5. The purpose of Task 5 is to analyze the capability of Eklutna Lake (Figure 1-1) to supply the 70 mgd of water to the area. The report of each task appears as an appendix to the Executive Summary of the entire study. This Appendix V is the report for Task 5, Eklutna Lake Alternative Water Source Evaluation. PURPOSE AND SCOPE The purpose of Task 5 is to identify one or more alternative water supply projects on or near Eklutna Lake, to screen these alter- natives, to compare them with the proposed Eagle River dam and reservoir project (Appendix 11, Preliminary Damsite Investigation), 1-4 and to make recommendations. Each alternative should be able to provide a safe water supply to meet the projected future needs of the Anchorage area. This study is to consider the proposed Eagle River dam and reservoir as the only other feasible source to meet the future demands. Impacts of the project on the exist- ing hydroelectric facility, such as reduced energy production and operational changes, also must be considered. This appendix contains discussions of the following: 0 Eklutna watershed � Existing hydroelectric project � Supply alternatives � Analysis of Eklutna Lake water as a potential potable water source � Cost, power, and energy considerations of the proposed alternatives and a 'comparison with the proposed Eagle River dam project � Environmental concerns for each alternative as compared to the proposed Eagle River dam project � Conclusions and recommendations Three alternatives were identified and analyzed. The conceptual layout of each alternative, the costs and associated impacts of each alternative, and recommendations for required future studies are presented to aid the Municipality of Anchorage in its compari- son of Eklutna Lake with the Eagle River as major water supply sources. Each alternative was developed to provide a 70-mgd water supply to serve the MAUS study area: Anchorage, Eagle River, Chuglak, Eklutna, Peters Creek, and Birchwood. However, prior to design of any Eklutna or Eagle River water supply facility, the MAUS demand projections should be updated. Current Municipality projections indicate that there are immediate needs to expand existing Anchorage Bowl sources. Each alterna- tive has elements that could be constructed in stages to accommo- date changing demands. The capital, operation, and maintenance costs were evaluated for each alternative. Particular emphasis was placed on the analysis of energy requirements and of impacts on the existing Eklutna hydroelectric facility. Energy requirements for any of the alter- natives and replacement energy for lost hydroelectric energy are assumed to come from a new source of energy at a cost substan- tially higher than Eklutna energy costs. 1-5 SITE DESCRIPTION Eklutna Lake is a high-altitude glacially formed lake. Eklutna Glacier now terminates several miles upstream of the lake. The lake is 30 miles northeast of downtown Anchorage and 16 miles northeast of Eagle River (Figure 1-1). It varies in elevation about 50 feet annually, with an average elevation of 845 feet above mean sea level. The waters of Eklutna Lake are turbid with glacial rock flour and have historically flowed down the 10-mile-long Eklutna River to the Knik Arm of Cook Inlet. In 1955 diversion of the lake water began for a hydroelectric project. This diversion substantially reduces the Eklutna River flows. The 30-MW Eklutna hydroelectric project diverts an average of about 300 cubic feet per second (cfs) of water through a tunnel under Coat Mountain to a powerhouse at the upper end of Knik Arm. The major project features are an earth and rockfill dam with an uncontrolled spillway crest at an elevation of 871 feet, a 640-square-foot screened intake, a 23,550-foot-long tunnel, a 1 , 39 5-foot- long penstock, and a powerhouse containing two Francis-type turbines, 15 MW each. The turbines extract about 800 feet of head from the lake water and normally control the lake. The average annual energy production is 155 million kWh, and total generation through August 1981 is over 4 billion kWh. The only major project shutdown occurred after the 1964 earthquake. LIMITATIONS This report has been prepared for the use of the Anchorage Water and Sewer Utilities for specific application to the Eagle River Water Resource Study, Eklutna Lake Alternative Water Source Evaluation, in accordance with generally accepted engi- neering practice. No other warranty, expressed or implied, is made. In the event of any changes to the conditions considered under this study, the conclusions and recommendations contained in this report will not be considered valid unless the changes are reviewed and the conclusions or recommendations are modified or verified in writing by CH2M HILL. The majority of the data used for this study was supplied by var- ious Federal and state agencies. Alaska Power Administration (APA) operation records and construction drawings of the Eklutna hydroelectric facilities were used for most of the alternatives anal- ysis. Except for water quality and treatability tests, no new field data were collected during this study. The conceptual alternatives presented in this report are believed to be workable, but the concepts are not refined enough for incorporation into a final design. Additional investigations will be required prior to final design of any of the alternatives. 1-6 On Chapter 2 00 EKLUTNA WATERSHED To evaluate Eklutna Lake as a water supply source for the An- chorage area, three drainage basins within the Eklutna watershed were studied (Figure 2-1): (1) Eklutna Lake, (2) Upper Eklutna River below Eklutna Lake and above the old Anchorage Light and Power diversion dam (the location of the old dam is shown on Fig- ure 5-1), and (3) Lower Eklutna River below the upper river basin, near the Old Glenn Highway bridge. The physical and hydrologic characteristics of each basin and of the entire Eklutna watershed are summarized in this chapter. DESCRIPTION The Eklutna watershed lies northeast of Anchorage and is about 26 miles away at its nearest point. The basin extends from Eklutna Glacier, high in the Chugach Mountains, to the Knik Arm of Cook Inlet, approximately 27 miles northwest of the glacier. The three basins within the study area drain to a single point on the river approximately 1/2 mile upstream of the Old Glenn High- way. The total area of the watershed is about 168 square miles. Eklutna Lake and its drainage area comprise close to 119 square miles, 71 percent of the total area. The Upper Eklutna River basin drains almost 19 square miles, and the Lower Eklutna River basin drains about 30 square miles. The topography of the area is very rugged, with elevations rang- ing from near sea level to over 8,000 feet, with many peaks over 7,000 feet. The upper end of the watershed contains several gla- ciers, including Eklutna Glacier. These glaciers constitute over 6 square miles of the study area. Eklutna Glacier, the largest, is a typical alpine glacier, almost 7 miles long. Downstream of Eklutna Glacier, the watershed consists of a steep-sided, trough- like glaciated valley, with widths varying from 2 miles at elevation 4,800 feet to about 400 feet at elevation 1,000 feet. Eklutna Lake covers most of this valley. At the upper end of Eklutna Lake, a stream from Eklutna Glacier forms a large delta. Several other streams draining the Chugach Mountains also empty into Eklutna Lake. Near the lower end of the lake, an intake structure and tunnel divert water from Eklutna Lake through Goat Mountain to the Eklutna hydroelectric power plant. The Eklutna hydroelectric facility regulates the lake sur- face elevation, which varies from about 825 to 870 feet on an annual basis. Lake depth averages about 200 feet. At the ex- treme lower end of the lake, glacial drift forms a natural barrier to most of the lake outflow. An outlet stream passes through this drift and into the Eklutna River. The Eklutna hydroelectric proj- ect dam blocks this stream and regulates the elevation of the lake. 2-1 Below the dam, the Eklutna River flows through a deep gorge cut through glacial drift and, in places, bedrock. The depth of this gorge varies between 50 feet and 500 feet before the river con- verges with Thunderbird Creek. Approximately 1 mile upstream of the convergence with Thunderbird Creek, the flow of Eklutna River is partially blocked by an old diversion dam, built around 1930. This dam was used to divert water for power generation by Anchorage Light and Power (AL&P), but now the area behind the dam is full of sediment, and water flows over the dam. Downstream of the confluence, the slope of the Eklutna River lessens and the river leaves the gorge area. As the river passes beneath the Old Glenn Highway, its floodplain begins to widen until, at its mouth, a large delta is formed. Thunderbird Creek's headwaters originate high in the Chugach Mountains. It, too, flows through a deep gorge on its way to confluence with the Eklutna River. Just above the confluence point, the creek passes over a waterfall. CLIMATE The climate of the Eklutna area is very similar to that of the Eagle River. Both temperature and -precipitation are moderate because of the climatic barrier formed by the Chugach Mountains. Approximately 6 years of climatic information, beginning in 1941, was recorded at the old diversion dam on the Eklutna River. Precipitation and temperature were recorded at Eklutna Lake be- tween 1947 and 1976. Currently, the nearest weather station to the Eklutna area is at the Eklutna hydroelectric facility, where climatic information has been gathered since 1952. The annual temperature in the lower reaches of the Eklutna water- shed averages about 33 degrees F, with the daily high tempera- tures averaging around 54 degrees F. Temperatures in the upper parts of the basin are considerably lower, as evidenced by the glaciers and the length of time snow is present in the basin. Precipitation in the Eklutna area is estimated to be slightly higher than in Anchorage. The average annual precipitation at the Eklutna hydroelectric facility, based on 15 years of record, is just over 19 inches per year. In the upper part of the water- shed, precipitation is much higher because of the proximity of the Prince William Sound area. HYDROLOGY Hydrologic data for the Eklutna Lake watershed have been gath- ered by various agencies. AL&P made estimates of runoff at the old diversion dam between 1929 and 1949. Fragmentary records of the storage change at Eklutna Lake were kept between 1942 and 1949. The USGS measured discharge at the outlet of Eklutna Lake between 1946 and 1962. It also gaged Eklutna Lake heights 2-2 t yt@ inbarh mer c I to? Four 3 20 PARK Uorn Vit ma 3 'A yBlac@17_-PNP Cif Down g'@ 1-4 r L tie i le V'W' iden., rig -W -,700-, @41 dy zoo'@ van, @@j L 47 ke --a ke IV, I reav? z Ott Wood t 1,'Ile _77777 SfI 4,m Ko I A Eldbtn4 meil 'e, .- ' Z. pi I w o, Pe:frs W -1 Mv ON& ;W ;ft' > -1 On. 7", IN 01 .4;z L A AY 'N MCI Goose Bay "2v tL_ UU \IV 'N A IT ZV 44 91T I A LI 4 01 Ta & '7717 77@ /'Ft g r 00 JL: @ @kj Hh@u kl Hh@u W 3@_ @J' @kl Glact @.+Ca 'id reA Un during part of this period. The most complete hydrologic records are kept by the various Federal agencies in charge of the Eklutna Lake hydroelectric project. These extend from 1947 through the present. The records are of estimates of the inflow to Eklutna Lake, outflow of Eklutna Lake through the power plant, lake ele- vation records, and estimates of spill over the dam. Eklutna Lake Basin The hydroelectric project's estimation of inflow to Eklutna Lake (Table 2-1) is based on project records of changes in the lake level, the flow through the power plant, spill over the dam, and any flow through the dam. Table 2-2 shows the outflow of Eklutna Lake by month between 1966 and 1980. The spill over the dam at the outlet of the lake is estimated by a weir equation based on the lake elevation. Leakage through the dam is based on visual inspection when the lake elevation measurements are made. When there is no spill from the lake or leakage through the dam, the water passing through the power plant constitutes the total outflow of Eklutna Lake. Flow passing through the power plant is recorded daily. The water used by each turbine is determined from turbine per- formance curves. Lake levels are normally measured on a weekly basis unless the lake is higher than the spillway, at which time daily measurements are made. Table 2-3 is a tabulation of the average monthly lake levels measured by staff at the hydroelectric facility. Upper Eklutna River Basin A relationship between Eklutna Lake outflow and the Upper Eklutna River basin inflow was derived by the Anchorage Public Utilities for water years 1940 through 1949. It was estimated that approximately 11 percent of the flow at the AL&P dam entered the Eklutna River from the Upper Eklutna River drainage area. Table 2-4 shows 10 years of estimated inflows to the area between Eklutna Lake and the AL&P dam. These flow values are derived from discharge records of Eklutna Lake and also of the old diver- sion dam for water years 1947, 1948, and 1949. Storage records of Eklutna Lake also were kept for these years. From the lake storage and the discharge measurements, the natural inflow be- tween the lake and the diversion dam was computed. The inflows for water years 1940 through 1946 were calculated on the basis of the average monthly percentage of runoff derived from the 1947 through 1949 records. 2-5 Table 2-1 I N FLOW TO EKLUTNA LAKE Water Inflow (ac-ft x10 3) Year' Oct. Nov. Dec. Jan. Feb. Jul - - - @a r June July Aug. Sept Total 1947 4.8 4.2 1.6 1.1 0.6 1.4 1.3 5.5 28.9 75.6 55.8 32.5 213.3 1948 14.3 7.3 4.5 3.2 0.8 0.8 0.9 7.3 33.3 59.0 56.7 17.2 205.3 1949 8.0 3.8 6.2 2.0 0.8 0.5 0.7 8.7 31.1 60.5 61.3 41.7 225.3 1950 9.1 6.0 3.6 2.3 0.9 1.1 0.7 3.2 36.4 62.5 70.0 18.8 214.6 1951 5.9 1.5 2.1 1.2 0.4 0.4 1.2 5.4 31.5 85.8 69.2 60.5 265.1 1952 9.1 4.9 2.6 2.4 0.4 0.7 0.3 2.5 23.4 62.4 49.4 20.0 178.1 1953 21.4 9.9 5.3 2.1 1.3 1.0 1.4 12.1 63.1 103.3 78.2 29.7 328.8 1954 13.5 4.8 3.1 1.1 0.2 0.6 0.6 9.5 36.2 63.4 73.4 33.4 239.8 1�55 11.7 7.2 5.9 2.2 2.0 2.8 2.6 5.2 22.2 69.5 54.8 23.8 209.9 1956 7.8 3.1 3.2 3.2 2.0 1.5 3.6 8.6 24.5 75.9 63.1 34.2 230.7 1957- 7.4 6.3 5.2 1.0 3.2 2.6 2.5 11.5 59.2 79.5 73.1 50.4 301.9 1958 11.9 7.1 4.7 4.1 2.2 1.3 3.0 12.9 52.2 68.8 57.7 13.1 239.0 1959 6.7 5.7 2.7 1.2 1.6 1.1 2.1 12.4 59.0 62.5 60.8 17.6 233.4 1960 9.5 6.0 5.1 1.8 3.2 3.1 -1.7 20.3 46.0 68.3 55.8 27.1 244.5 1961 11.6 5.5 6.3 7.5 3.8 2.0 1.1 12.8 39.7 64.9 62.4 34.9 252.5 1962 12.4 5.6 2.9 2.4 1.8 1.8 3.5 7.6 43.6 69.3 61.9 21.3 234.1 1963 6.9 5.1 3.2 2.9 2.1 1.8 2.6 11.7 25.5 73.5 72.0 30.6 237.9 1964 8.2 3.5 4.3 1.2 1.9 -1.0 4.3 9.0 52.0 61.8 48.1 21.9 215.2 1965 6.9 5.3 0.8 0.3 -3.9 3.8 4.5 5.3 18.5 49.2 53.8 46.1 190.6 1966 11.9 3.7 5.0 1.8 1.8 1.9 2.7 5.9 42.1 68.1 63.2 36.1 244.2 1967 16.0 6.0 3.6 3.3 0.1 3.6 -1.0 9.7 43.7 67.1 76.3 51.9 280.3 1968 46.7 6.6 4.0 7.0 0,9 2.5 1.6 13.4 37.2 67.7 65.2 19.0 271.8 1969 6.5 5.6 2.9 0.6 0.1 1.2 3.2 13.2 46.2 63.9 31.2 16.7 191.3 1970 21.9 6.5 4.6 3.0 1.3 2.8 3.8 7.5 29.9 48.5 45.1 22.0 196.9 1971 5.5 10.1 1.6 2.6 0,7 2.0 1.9 3.4 25.6 70.3 81.0 20.6 225.3 1972 8.9 5.4 1.1 0.6 0.1 2.3 1.9 6.0 21.4 70.1 63.7 34.7 216.2 1973 4.7 5.2 0.1 2.6 1.7 7.4 5.5 3.7 20.6 54.4 44.4 14.8 165.1 1974 5.9 2.9 2.4 1.9 -1.2 5.5 .1 1.8 27.5 50.0 57.4 43.6 197.8 1975 3.2 7.2 4.0 -5.3 1.1 3.1 2.8 13.4 21.3 68.9 53.7 25.8 199.2 1976 8.9 -1.1 4.6 1.1 1,4 5.5 -5.4 10.6 26.2 70.8 49.8 37.2 209.6 1977 12.0 8.6 13.3 0.2 2.3 7.1 8.6 -1.6 50.7 84.6 84.9 37.1 307.8 1978 15.1 7.6 -0.7 6.7 2.2 0.8 1.9 13.9 24.1 59.5 59.7 34.1 224.9 1979 10.9 5.5 5.5 0.9 3.2 7.7 4.1 9.9 29.8 79.5 72.2 37.6 266.8 1980 17.8 7.8 5.8 5.4 3.8 0.3 10.0 14.2 27.9 87.9 61.8 9.9 252.6 1981 7.8 8.2 7.5 19.1 4.7 13.3 -0.8 8.4 57.9 66.6 84.4 9.0 286.1 Monthly Average 11.2 5.7 4.0 2.7 1.4 2.7 2.2 8.7 36.0 68.4 62.0 29.3 234.3 Notes: 1. One acre-foot per month = .0109 mgd = .0168 cfs = 7.54 gpm (30-day month). 2. Negative values represent revisions. Data Source: Operations records of the Eklutna Hydroelectric Project. 2-6 Table 2-2 OUTFLOW OF EKLUTNA LAKE Water Outflow a (acre-feet) Year Oct. Nov. Dec. Jan. Feb. Ma r. Apr. May June- July -Aug. @@e- p . Avg. 1966 13,947 15,650 12,980 14,769 12,807 13,889 13,175 19,426 16,151 16,607 18,217 18,065 15,474 1967 15,494 20,529 18,599 20,328 18,098 23,643 21,570 21,235 18,679 23,725 23,694 20,732 b 20,527 1968 24,317 b 13,026 23,972 23,340 21,579 19,544 18,111 19,453 16,674 16,680 20,007 10,046 b 18,896 1969 22,518 b 22,618 17,935 19,599 19,131 21,192 16,233 17,241 21,186 22,867 22,179 20,108 20,234 1970 17,946 19,046 20,462 21,016 16,089 18,263 14,898 16,466 21,955 22,416 18,174 14,039 18,398 1971 14,737 19,820 23,355 18,202 12,742 8,978 6,866 13,437 19,624 19,760 19,013 17,629 16,180 1972 23,916 21,480 28,182 28,296 25,073 22,251 8,308 8,022 14,978 19,093 17,380 19,147 19,677 1973 23,040 24,393 22,596 21,571 14,917 15,133 14,017 13,313 11,576 6,860 8,709 10,194 15,527 1974 9,667 15,894 13,134 14,172 13,766 12,531 11,636 16,587 19,199 14,416 16,355 13,092 14,202 1975 14,871 21,394 18,963 22,139 17,469 14,764 12,112 9,683 12,254 18,045 14,915 16,026 16,053 1976 17,990 21,867 21,843 18,876 17,570 14,394 15,293 17,239 12,297 13,300 13,048 13,386 16,425 1977 13,976 12,241 16,824 17,927 17,090 20,771 17,165 27,409 23,040 26,761 30,625 b 30,231 b 21,172 b 1978 27,393 20,897 21,695 25,079 21,057 21,194 221,727 16,512 23,794 25,649 25,849 23,319 22,930 1979 17,268 16,547 15,459 13,280 10,541 21,638 23,268 24,176 19,476 21,873 19,686 18,744 18,496 1980 25,459 21,723 23,581 21,182 16,236 21,159 17,328 31,842 25,884 22,499 32,072 23,602 23,547 aBased on actual water used at the power plant. b Lake spilled during these months. Data Source: Operations records of the Eklutna Hydroelectric Project. Table 2-3 EKLUTNA LAKE WATER SURFACE LEVELS Wa ter Elevation (feet) I ea r Mar. Apr. May June July Aug. ep. 1955 B64,4 860.8 857.8 855.0 852.6 852.5 863.3 869.5 869.5 1956 867.8 865.4 861.5 856.3 852.3 8411.1 843.9 841.3 842.3 854.5 868.3 868.8 855.9 1957 867.0 863.4 859.1 854,4 849.7 B44.4 839.6 836.3 845.8 867.3 869.5 869.4 855.0 1958 868.1 866.7 862.8 857.6 853.6 849.3 844.0 839.3 843.6 856.0 867.2 868.1 856.4 1959 865.0 860.0 855.0 849.8 843.9 838.2 832.8 828.7 833.1 848.8 860.0 867.4 848.6 1960 865.3 861.7 857.0 851.6 846.2 840.3 833.6 828.0 832.1 844.3 858.3 864.0 848.5 1961 863.5 059.3 853.9 848,1 842.9 836.3 828.0 821.0 821.2 831.3 847.0 856.5 842.4 1962 858.4 853.1 846.3 839.3 833.1 $25.9 819.5 815.5 815.7 833.3 849.3 858.0 837.3 1963 856.5 853.0 848.6 844.6 839.9 835.4 831.4 828.8 830.1 841.8 856.4 865.8 844.4 1964 864.0 859.3 855.0 851.7 846.5 839.9 835.0 833.0 842.6 857.0 861.4 859.6 850.4 1965 855.5 848.8 842.1 832.6 823.1 814.0 820.5 830.8 840.4 1966 847.2 844.2 840.7 837.3 833.3 829.3 825.3 821.5 822.3 835.9 853.6 862.3 837.7 1967 865.2 862.8 858.0 852.9 847.5 841.4 834.0 828.3 829.6 842.3 857.4 B69.0 849.0 1968 870.5 867.8 863.8 857.3 850.9 844.6 839.5 834.7 837.0 050.0 864.3 870.5 854.2 1969 869.3 863.9 858.4 853.0 847.4 841.7 835.3 832.9 834.8 848.0 856.3 856.5 849.8 1970 856.9 855.3 850.3 845.3 839.0 835.5 830.8 026.5 826.3 832.0 842.0 847.5 840.7 1971 847.4 873.1 838.5 832.6 827.7 824.0 022.1 819.9 817.1 826.1 847.3 858.4 836.2 1972 856.4 851.8 844.3 835.5 827.0 818.0 812.8 811.2 811.1 820.8 838.2 849.0 831.4 1973 849.4 843.0 836.4 829.5 823.6 819.5 B16.4 812.4 811.0 821.7 836.9 844.2 828.7 1974 844.0 842.0 837.7 833.9 829.3 825.4 022.2 820.1 820.9 826.6 840.4 852.9 833.0 1975 857.9 8541.6 849.0 844.2 037.0 832.1 827.7 825.6 826.8 837.2 852.8 860.3 042.2 1976 860.9 856.6 850.6 844.7 0311.9 032.8 829.3 824.2 822.6 833.6 851.3 857.9 842.0 1977 864.9 863.8 862.9 860.3 B54.3 849.8 844.6 838.3 834.3 848.4 869.0 872.4 055.3 1978 869.7 866.0 061.2 855,3 848.4 842.6 836.1 831.0 830.0 835.0 848.5 855.4 848.3 1979 856.2 854.1 850.3 846.6 843.6 839.6 832.2 825.7 823.3 832.9 853.0 864.6 843.6 1980 867.5 864.2 860.3 854.5 B50.1 845.5 840.0 833.7 829.7 839.2 858.3 062.7 850.5 1901 865.3 865.3 862.3 860.4 855.5 848.5 839.0 833.7 839.6 853.9 867.4 872.1 855.3 Average 66-80 859.0 857.6 850.9 845.5 839.9 834.8 829.9 825.7 825.1 835.3 851.3 859.0 842.8 -Records incomplete. Data Source: Operations records of the Eklutna Hydroelectric Project. Table 2-4 ANCHORAGE LIGHT AND POWER DAM INFLOW LESS EKLUTNA LAKE OUTFLOW Water Inflow Less Eklutna Lake Outflow (ac-ft x 10 3) Year Oct. Nov. Dec. Jan. Feb. Mar. _@pr. y2y Lune @uly =. 1@ept.@a - - - - - at 1940 10.8 0.6 0.4 1.5 1.5 1.3 0.9 2.0 4.0 3.7 7.3 7.1 41.1 1941 9.7 0.3 0.4 1.5 1.7 0.9 0.6 1.0 6.0 3.4 5.8 2.9 34.2 1942 3.2 0.2 0.6 2.3 1.9 1.0 0.6 6.2 4.4 2.4 2.6 4.3 29.7 1943 7.5 0.2 0.3 1.3 1.0 0.4 0.4 1.3 2.3 1.2 4.5 1.9 22.3 1944 3.5 0.5 0.5 1.7 0.8 0.4 0.5 3.0 6.4 4.2 8.8 3.3 33.6 1945 4.3 0.2 0.3 0.9 0.8 0.3 0.4 2.5 4.7 3.8 6.1 2.3 26.6 1946 5.0 0.1 0.1 0.8 1.0 0.5 0.4 2.7 5.2 4.1 4.3 2.9 27.1 1947 3.0 -1.3 0.2 0.2 0.0 -1.0 0.9 0.6 4.3 1.0 4.2 6.4 16.3 1948 9.0 1.2 1.7 2.0 5.0 3.3 2.2 4.9 5.0 4.9 5.6 0.7 45.5 1949 1.4 0.8 0 4.2 .5 0 0.3 1.2 2.0 3.8 -1.1 2.8 15.9 Average 5.7 0.3 0.4 1.6 1.4 0.7 0.5 2.5 4.4 3.3 4.8 3.2 29.2 Percent Average 238 12 17 68 59 29 22 105 184 135 200 131 100 D-ata_S_o_u_r_c_e:__1J . S . Bureau of Reclamation, 1950. Note: Negative values represent revisions. 2-8 At present, very little water from Eklutna Lake flows to the Ek- lutna River above the old diversion dam. For this analysis, an- nual runoff between Eklutna Lake and the old diversion dam was estimated on the basis of drainage basin size. Monthly flow dis- tribution was also estimated, using a monthly distribution similar to that of Peters Creek. Peters Creek was chosen because it is a fairly small basin with only a few glaciers and is adjacent to the Eklutna watershedf indicating that climatic conditions are sim- ilar. A comparison of these monthly flow estimates with the An- chorage Public Utilities records of the 1940's indicates that the annual runoff as predicted by the basin size is fairly accurate. The monthly runoff distribution differs slightly but is considered to be a good representation of actual flows. Lower Eklutna River Basin Flows from the Lower Eklutna River drainage basin also were es- timated from basin size and the monthly distribution of Peters Creek. Eklutna River-Thunderbird Creek Monthly Flows Figure 2-2 shows the predicted average monthly flows for both Thunderbird Creek and the Eklutna River between the lake and the old diversion dam. Also shown is an estimate of the monthly fish flow requirements at the confluence of these basins. The fish flow requirements are based on 30 percent of the average annual flow during the summer months of June through September and on 30 percent of the average winter flow during the months of October through May. The monthly differences between the combined Thunderbird Creek and the Eklutna River streamflows and the required fish flows are estimates of the amount of water that potentially would be available for use by the Municipality of Anchorage. Actual downstream flow requirements should be estab- lished prior to diversion. LAKE ICE Careful consideration of ice effects on potential intake structures on Eklutna Lake, Eklutna River at the old diversion dam, and on Thunderbird Creek is required. Potential problems include growth of ice on water surfaces, ice jamming in the vicinity of the structures, ice forces, and frazil ice production and accumu- lation. Ice growth on lake and reservoir surfaces will decrease the avail- able storage for water supply. Usually 3 feet of ice forms on Eklutna Lake during the winter, but it is estimated that 4 feet or more of ice may develop during colder years (about 12,000 ac-ft of storage). The volume occupied by ice above the old diversion dam or a new diversion dam is not known, but it could be significant. 2-9 Ice jamming at the old diversion dam and on Thunderbird Creek could occur during spring breakup if the ice cover on either stream is fairly solid when high spring flows begin. High flows could break up the ice and force it against any structures in the river. The force of these ice flows must be considered in the design of any intake or impoundment structures on the Thunder- bird Creek and Eklutna River. Because both streams are fairly steep, large quantities of frazil ice may regularly form, which could seriously hinder water works. No mention of operational problems resulting from frazil ice can be found in the literature for the old hydroelectric project on Eklutna River, but the Municipal Water Treatment Plant on Ship Creek occasionally receives large quantities of frazil ice. The Municipality is considering the use of waste heat from natural gas energy generation to combat the short but intense periods of frazil ice accumulation at the Ship Creek treatment plant. Frazil ice production should be evaluated during design of any structures on Eklutna River or Thunderbird Creek. A winter ice survey similar to that discussed in Appendix 11, Preliminary Dam- site Investigation, would be invaluable. SEDIMENTATION Sedimentation in the Eklutna watershed occurs in both Eklutna Lake and the small lake above the old diversion dam. The sedi- ment is caused mainly by glaciers and by a combination of steep terrain, lightly vegetated areas, and moderate to heavy precipita- tion in parts of the basin. Eklutna Glacier, whose toe is about 4-1/2 miles from the upper end of Eklutna Lake, is the main contributor to glacial sediment in the area. A considerable amount of glacial material has been deposited at the upper end of the lake, forming a large delta. A portion of the very fine sediment coming into Eklutna Lake is carried through the lake to both the Eklutna River and the hy- droelectric facility. This is evidenced by the turbidity and vis- ual "milkiness" of the water. Sediment moving down the Eklutna River is partially trapped behind the old diversion dam. Estimates of sediment accumulation in Eklutna Lake and above the old diversion dam were made by Anchorage Public Utilities. These estimates indicate that sediment accumulates above the old diver- sion dam on Eklutna River at a rate of 1.70 ac-ft per square mile per year. The sedimentation rate at Eklutna Lake has been esti- mated by the USGS at 10,000 ac-ft per 50-year period. Actual sediment measurements indicate that this estimate is high. The amount of sediment passing through the Eklutna power plant is lower than previously predicted. The rate of sedimentation of Eklutna Lake could have a long-term effect on any diversion project on Eklutna Lake. A program to measure the sedimenta- tion rates should be made to predict more accurately the actual sedimentation rates. 2-10 120- -180 110- 100- -150 90- 80- E -120 3: 70- 0 0 -j 60- 90 -j U. LL 50- 40- 60 30- 20- 30 10- - - - - - - - - - - - - - - - - - - - - - - - - I- - - - - - - - - - - - - - 0- .0 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP COMBINED FLOW OF THUNDERBIRD CREEK MAXIMUM AND EKLUTNA RIVER BELOW EKLUTNA LAKE DIVERSION TO ANCHORAGE (mgd) FLOW OF EKLUTNA RIVER AT OLD ANCHORAGE LIGHT AND POWER DIVERSION DAM OCT 23.7 APR 3.9 ESTIMATED FISH FLOW REQUIREMENTS NOV 13.6 MAY 15.0 DEC 10.2 JUN 59.3 JAN 8.0 JUL 70.0 FEB 6.3 AUG 64.6 MAR 4.2 SEP 39.4 Figure 2-2 Eklutna River- Thunderbird Creek Watershed Available Monthly Flow LAKE EVAPORATION The effect of evaporation on the amount of water available at Eklutna Lake is inherent in the hydroelectric facility estimates of lake runoff. Therefore, further study of the evaporation rate at Eklutna is not necessary. 2-12 Chapter 3 EXISTING EKLUTNA HYDROELECTRIC FACILITY HISTORY The current Eklutna project was built as a single-purpose 30,000- kilowatt-plus project by the United States Bureau of Reclamation to serve the expanding electrical needs of the greater Anchorage, area. The project is operated by the APA. (Figure 1-1 in Chap- ter 1 shows the relative location of the project and lake with re- spect to the Anchorage area.) The project went on line in 1955 after a 4-year construction period. Its construction diverted most of the flow from Eklutna Lake through a mountain ridge and di- rectly into Knik Arm (except during infrequent periods of spill) and required the abandonment of the Anchorage Light and Power Company hydroelectric facility on the Eklutna River. Facilities remaining from this abandoned project include the dam (now silted to the crest), the diversion tunnel, the penstock, and the power- house. All electrical and mechanical equipment has been removed from the old powerhouse. EXISTING FACILITIES The Eklutna project survived the 1964 earthquake with some dam- age, but was able to provide power at a reduced capacity until repair work was begun. The project was shut down several weeks during repairs. The main features of the Eklutna project are the dam, reservoir intake, tunnel, surge tank, penstock, power plant, and tailrace. Figure 3-1 shows the locations of all these features except the dam. Major engineering considerations, including post-earthquake modifications, are as follows: Reservoir (as Modified) Location: Approximately 10 miles southeast of Eklutna power plant and 30 miles northeast of Anchorage Reservoir statistics: Total live capacity: 213,271 acre-feet Active capacity: 174,798 acre-feet Present inactive capacity: 38,473 acre-feet Surface area (at total capacity): 3,420 acres High-water elevation (spillway crest): 871.0 feet Length: 7 miles Width: 0.7 mile Depth: 200 feet 3-1 --SUMMIT E1.5340 GOAT DIA. GATE SHAFT, ,EI.1015 MOUNTAIN -EI.905 ,-EKLUTNA LAKE 115-KV 3d DI& SURGE TANK---- TRANSMISSION FIXED WHEEL GATE (OPEN)-, Ll N ES-, It El.800-11 El. 791 ANCHORAGE- 4TO p pkGE E1.713-,. PALMER "Atic"o HWY ----------- - INTAKE '-PRECAST CON I it, S=.00341 STA.266-38 TO STRUCTURE- STA.27-25--.: PAL iWee 9'DIA. CONCRETE LI N E D TU NN EL 23,550 FT LON.G-' STA. 255 30" L 25-, 0 PROFILE El. 15 INTAKE POWERHOUSE-' STRUCTURE- -.--HIGH WATER LINE TAILRACE -ROAD STA.254-65.67--@ ,--ACCESS CHANNEL---'-'-' TUNNEL 0 PENSTOCK-" GATE SHAFT SURGE TANK KNIK RIVER PLAN TAILRACE CONDUIT-- BEFORE 1964 EARTHQUAKE -SUMMIT E1.5340 GOAT I DIA. GATE SHAFT-, !1, 1015 MOUNTAIN -El.905 1 115- KV -EKLUTNA LAKE 3d DIA. SURGE TANK-- . TRANSMISSION MAxWS884.8-- LINES-,, I FIXED WHEEL GATE (OPEN)-,, ANCHORAGE- To E1.800-1, A05kgGE I I :: : ; @ E1.791 E1.713-, PALMER A%Cli ...... HWY-- : "'o STA.266-38- OLD INTAK , '0 ECAST CONDUI Sm-00341 STRUCTU E` 40 @O PAL.VER STA. 27-25--' 2 NEW INTAKE STRU U E, STA. 255- 30-` El. 25-, '0 0 9'DIA. CONCRETE LINED TUNNEL 23,550 FT. LONG' PROFILE NTAKE STRUCTURE E1.15 OLD INTAKE ,,NEW I POWERHOUSE" STRUCTURE- -HIGH WATER LINE TAILRACE (ABANDONE -ROAD STA. 254 - 63.67- 0-ACCESS CHANNEL ------ TUNNEL ------------------- PENSTOCK-- KNIK SURGE TANK- `-GATE SHAFT RIVER PLA N TAILRACE CON DU I T- AFTER REHABILITATION FOLLOWING EARTHQUAKE DAMAGE SOURCE: U.S. Bureau of Reclamation. 1967. Figure 3-1 Eklutna Project Features 3-2 Schematic Plan and Profile Dam (as Replaced) Type: Earth and rock fill Foundation: Firm glacial till Slopes: 3-to-1 upstream, 2-to-1 downstream Slope protection: No special slope protection; rockfill (zone 3) was placed in 3-foot layers on both upstream and downstream faces Crest length: 815 feet Crest width: 30 feet Crest elevation: 891 . 0 feet Volume: 85,000 cubic yards Spillway (as Replaced) The spillway plan and cross-section are shown in Figure 3-2. Location: On right bank but almost midway between abut- ments of dam Ty pe: An ungated overflow crest with a rectangular rein- forced concrete conduit through the dam and a still- ing basin energy dissipator Crest elevation: 871 .00 feet Crest width: 18 feet Capacity: 3,315 second-feet with reservoir at maximum (surcharge) elevation 884.8 Flood routing curves are shown in Figure 3-3. Intake Structure (as Replaced) Location: Eklutna Lake bottom Type: Rectangular reinforced concrete box structure, open and protected by trashracks on its top, front, and two sides Dimensions: Trashracked portion about 23 feet wide, 20 feet high, and 22 feet long in direction of conduit flow; 42 feet 4 inches in overall length Elevation of invert: 793.6 feet, which is 77.4 feet below the dam spillway crest Inlet channel: 100 feet wide, about 720 feet long (original intake structure and portions of original in- take conduit remain in inlet channel) Eklutna Tunnel Cross-sections of the Eklutna tunnel are shown in Figure 3-4. Type: Circular, concrete-lined, pressure type Inside diameter: 9 feet Length: 23,550 feet Hydraulic properties: Area: 63.62 square feet Velocity: 10.06 feet per second Capacity: 640 second-feet 3-3 x e -- --------- 7-- 7 "d 's b'd-9 w, A- -d E-1 srcrioii A-A 3 11@ R-P Orr- d y ------ sEc"o. 6-8 --- -------- PROFILE ON f SPILLWAY A OCT-L z T- 1-2 -g -- -------- C, il-7 -d. I-. C,*" ON C-C SE.T, L -8 7-- S-rION E-r sEcr,oN 6-0 Id -I.. C.- -Pz S. SECT- D-D A-1 - 9rcrioN r-r SOURCE: U.S. Bureau of Reclamation. 1967. Figure 3-2 Spillway of IN General Pla Sections SPILLWAY DISCHARGE - 1.000 C.F.S. 0 3 4 5 RESERVOIR CAPACITY - 10.000 A.F. Se 20 21 22 IN IFLOWIDESI IGN FLOOD 213 214 25 .6 -Peak 16,115, C. fs. 3 Day volume 58,300 AF Max. storage - 246, 330 7 5 Day volume 64, Poo A. F. 1 1 1 1 - Is ass I I MOA. WS. E-1 88-1 ,eo@; -W 5@ El, 884.55 -Max 0 z 3315 cfs I I @ 14 -Time - storage curve _,X-Spillway discharge 12 6 1' 0 Ct Reservoir copoci ty 0 Sao La W S. El. 877.521 for flow 000 c. f s. /aIoding STS a --"Ow "ydrograph -PSOA 5,625 C.f S. 6 4 872 'Sjadlvvo@ cr..@@_ E, , '7' 0 0700-- 5 __ 6 7 0 TI.1 IN DAYS NOTE: Reservoir capacity taken from table dated April, 1963. -4 14@Clll A 41-," SOURCE: U.S. Bureau of Reclamation. 1967. Figure 3-3 New Dam Spillway Flood Routing Curves -G pq, s a-ched Gra,,f p,pe 5 OS -ilected romber spreaders to be removed before piocog concr& LO99.9 L -,2 0"- Lange pars 9 4 Line- 51 51, 1 Barrel 9,@ f Sorrel re awls Long" bars Circular hoops 4,111- C-,,iar hoops Stoner lops a, directed. Stagger tops as directed 9 Line TYPE I UNSUPPORTED TUNNEL SEC TION t OW "Circular hoops Stoner eld' or fops on outside hoops 04 each st@e -6rout pipes as drected Longf reinforce. of vertical 0-, and -de hoops 24 each Side, Of h C"c0p, 'Oop, Oil 3@ -ILA -32- 0Lphqt bars each face Pow swface a' 'O"t LM90 reinforcement to prevent bond 9Rtibber Ah" See Wor hoops ovig O_ro 67t, details TUNNEL SECTION TUNNEL CONTRACTION JOINT DETAIL 20 00 00 ro S I.t 21-11 301 Piece anhochoh jaw, at 25'@,hlervols upstream from Sto 27- 5 SCALE OF FEET E,pons,on de"ce- 7 Grout pipes 05 directed GrOul Pipes as dorecled l'0,a pot support anctw bolts in 'j Ahn Did holes tength and' spacing of bolts as directed Fasten to =qart Ifeel plate, as ",cf@ @el jpi@, 4 L he- llo,,,,,, spreaders and polls no, S,a_ ,60,1 ,"Longe po,ed as sho- )r, D,C-- X! If 010 1 Bo,ref ',Circ.la hoops 0 6 Stoner lops as directed Stoner laps as directed. -1 Lango' har, TYPE2 rr E3 SUPPORTED TUNNEL. SECTIONS STA 208,00 @ 10 ST. -9-Op. TUNNEL REINFORCEMENT FROM TO NOTES STATION SUTION LONGIT HOOPS REMARKS Place oil reinforce, ,jent so that the centers at bars in the otiter r .11 be Z., from face of concrete unless omwvvw show ---i4 '000 30- 0 1 0 6D lo' Looloye S ---77+385 44+000 @ 000 0 09, CO oil bars 34 diameters Of splices ncrele desigh posed on a compressive strM91h of 3,000 pounds --TF*-0-0-0 -190 @ -?5D - Unredorced per square inch @90+250 -793 @ ?5:0 to 6" H93 +250 - 206 * 500 - U"einforced 206+50,0 io-8+ 0-0 -2 30- 1 6D 8, _io_ 206 00 9+001 - hon 3 2i5+oao 30- 0 254ft5O 30- * SOURCE: U.S. Bureau of Reclamation. 1967. Figure 3-4 Pressure Tunnel Sections and Detail 3-6 Station 20+00 to 255+10 Slope: 0.00341 (80-foot difference in elevation between inlet and the outlet gate at surge tank) Closure: The details of the tunnel closure near the surge tank are shown in Figure 3-5 Surge Tank Location: 22,805 feet downstream from bulkhead gate shaft and directly over tunnel Height above tunnel: 176 feet Inside diameter: 30 feet Wall thickness: 18 inches Type: Restricted orifice Penstock Location: Downstream of surge tank Length: 1,395 feet Variable diameters: 91-, 83-, and 75-inch outside diameters Type: Welded and coupled steel pipe encased in concrete Plate thickness: 5/16 inch for initial section and variable up to 1-1/2 inches at terminal section Profile: A horizontal run of 30 feet, then descending 864 feet at an angle of 53 degrees, then a horizontal run of 501 feet Water Rights Permit Number: 44944, State of Alaska Quantity: 700 cfs Power Plant A location map of the Eklutna power plant is shown in Figure 3-6. Location: Adjacent to Old Glenn Highway, 34 miles northeast of Anchorage Type: Reinforced concrete Maximum head: 850 feet as originally constructed; 865 feet with new dam. Number of units: 2 Installed capacity: 33,334 kilovolt-amperes Turbines: Francis type, 25,000 horsepower at a rated speed of 600 revolutions per minute and an 800-foot ef- fective head Generators: Vertical-shaft type, 16,667 kilovolt-amperes at 90-percent power factor, 3-phase, 60 cycles, 6,900 volts Transformers: Two main power transformers, 3-phase, 60 cycles, forced-air cooled, 20,000 kilovolt- amperes, 6,600 to 115,000 grounded wye-volts 3-7 45-00, lb 1,2 95 E, 71 '1, 5' Hoops ottrod I WhW@ OWCOPW by add @,4 Poe, .10 SECTION A-A OP 87 .6 -1," Hoqp@ P 6'intwOrOWS 2`6 C co@StNc` ON JoW /0/;/ Sto 255 OP 9 8A C Tun 0) At 6 to 0 U.) Sto ?54,150, Itoll NOTES B ------- `H@,V@OD3'b,t-n St. 114@150 IS'. Ploc, .1 -f-owwl w MW fft 'wv. of bors in W -it 25-4 -6,5 P: 255 02 9 8@ - - - ouror ewrs wwr be f'f@ tft fboo of owroto LN*@ offt-M M.- N-Mv @Iofo doSW &MOd . o 0"lWh -*1d, W NVI sho's budt SECTIONAL PLAN fADIT LONNECTION TO TUNNEL Add 'i". 5- Vogg- top, o, d-111d tr dr 'd fr- 783-D-!53 E, 71@ 70 Hopp, off-d w1wr, rf-pted ------- -- J"*08' by Mt -------- It'* Hwp@ OD 5 SECTION C-C SEC TION B-8 SOURCE: U.S. Bureau of Reclamation. 1958. Figure 3-5 Pressure Tunnel Adit Closure Details (s- 1. D Ik" V KEY MAP '14 W-, A -le o,eC f,r -1 P-h- e.c R. El 4 R-_ T, RQ. W ILIII AL 1. A, 4- SOURCE: U.S. Bureau of Reclamation. 1967. Figure 3-6 Eklutna Hy Location M Switchyard Location: At three levels, on and adjacent to the power plant: roof elevation, 92.50 feet; intermediate roof elevation, 58.54 feet; and ground level elevation 41.25 feet Number of units: Two 115-kilovolt bays One 12.47-kilovolt bay Tailrace Location: Extending north from power plant under Old Glenn Highway Type: Combination pressure type and open channel. A re- inforced concrete pressure conduit 209 feet long and of varying width and depth discharges into an open channel with a bottom width of 25 feet, side slopes of 2 to 1, a depth of 12. 5 feet, and a length of about 2,000 feet, that conveys the water into the Knik River. ENERGY OUTPUT Prior to construction, the Eklutna project was intended to yield 143 million kWh of firm energy -and 16 million kWh of nonfirm energy (mostly during the summer and early fall) in an average year (U.S. Bureau of Reclamation, 1950). Table 3-1 presents the actual total energy output, by year, for the project. These figures show that the plant has generally met or exceeded its total generation targets, with the major exception of the drought year of 1973. Table 3-1 EKLUTNA GROSS GENERATION Year Total (kWh) Year Total (kWh) 1955 102,523,000 1969 167,986,000 1956 127,779,000 1970 155,422,000 1957 154,339,000 1971 144,515,000 1958 166,953,000 1972 164,680,000 1959 165,771,000 1973 96,854,000 1960 188,178,000 1974 125,624,000 1961 198,825,000 1975 135,609,000 1962 150,521,000 1976 118,508,000 1963 156,508,000 1977 204,182,000 1964 159,138,000 1978 180,650,000 1965 135,343,000 1979 171,615,000 1966 138,863,000 1980 184,814,000 1967 184,159,000 Tota 1 4, 043, 613, 000 1968 164,263,000 Average 155,520,000 Data Source: ETU'Utna Hydroelectric Facility Operating Records. 3-10 NN Chapter 4 00 SUPPLY ALTERNATIVES Previous studies have identified several projects on or near Eklutna Lake that could provide a water supply for the Munici- pality of Anchorage. These projects include diversion of water from the tailrace of the existing Eklutna hydroelectric facility, diversion of Eklutna Lake water by tapping the hydroelectric pro- ject penstock, pumping water from Eklutna, Lake and transporting it through a pipeline along the Eklutna Lake Road, and developing a new lake tap for gravity flow from Eklutna Lake by pipeline. Our review of the area's potential indicates that additional supply can be developed by diverting runoff water from the Eklutna River watershed below Eklutna Lake. Many possible alternatives can be developed from the various com- binations of supply and diversion points, treatment locations, and pumping facility locations. Additionally, it is possible to stage the construction of system components to meet increasing demands. POSSIBLE DIVERSION SITES In this study, three places were considered for diversion from Eklutna Lake: the Eklutna power plant tailrace, the Eklutna power plant tunnel, and directly from the lake. The power plant penstock is not a feasible point of diversion because of possible serious effects to downstream hydraulics and possible impacts to operation of the hydroelectric facility. Any diversion of water upstream of the turbines will reduce hy- droelectric energy output, and any diversion of water below the turbines will require large amounts of pumping energy. It is assumed that diversion of water from the tunnel near the existing surge tank would have only a single source of supply, Eklutna Lake. A tailrace diversion or a diversion directly from the lake is assumed to be supplemented by water from the Eklutna River watershed below the lake (Eklutna River and Thunderbird Creek). These supplemental diversions would reduce pumping energy requirements and any impacts on the hydroelectric facility. Water from the Eklutna River and Thunderbird Creek could be diverted either at the old Eklutna River dam or downstream at the Old Glenn Highway bridge. Project energy requirements would be lower with a diversion from the old dam because it is approxi- mately 150 feet higher than the lower site. However, for pur- poses of this study, the lower site was chosen because it has more water available, it is much more accessible, and it doesn't depend on a 50-year-old structure whose condition is not known. Before the abandoned dam and tunnel could be incorporated into a.project, their structural integrity must be determined. 4-1 The estimated annual water diversion during an average water year to meet increased demands is shown in Figure 4-1* for each diversion source. The curve representing the diversion from the Eklutna power plant tunnel also represents the total project diver- sion requirements. Each diversion offers distinct advantages and disadvantages, and various combinations of diversions are possible. The following descriptions note advantages and disadvantages of each principal diversion site. Tailrace A diversion from the Eklutna hydroelectric facility tailrace offers the following advantages: 0 Unless the operation of the facility is changed, for ex- ample, to power peaking as the primary function, there will always be at least 70 mgd coming through the tailrace 0 Staged construction potential Its disadvantages are as follows: 0 Difficult construction of the pipeline from the tailrace to the village of Eklutna 0 High pumping energy requirements 0 Possible hydroelectric facility emergency shutdowns This diversion may or may not be institutionally acceptable. It is preferred by the APA because it does not interfere with the op- eration or the capacity of the Eklutna hydroelectric facility nor does it reduce the facility's total annual energy generating capa- bilities. Also, the APA has maintained since 1978 that the tail- race diversion is better than diverting water upstream of the tur- bines because of lower pipeline design pressure requirements and staged construction opportunities." However, the pumping facili- ties may conflict with a fish hatchery, proposed by the Cook Inlet Aquaculture Association, to be located between the Old Glenn Highway and the power plant tailrace on land leased from the Federal Government. (Cook Inlet, 1981). The request for *The figures have been placed at the end of the chapter so as not to impede the flow of the text. "Correspondence from Bob Cross, director of the APA, to William Lloyd, MAUS Study Manager, U.S. Corps of Engineers. Novem- ber 22, 1978. 4-2 proposal indicates that the proposed fish hatchery will be ready for operation during the 1982 brood year. The use of mitigating measures such as fish screens or louvers at the pump station can protect the proposed fishery. Another possible means of reduc- ing potential problems in this area, which was recently suggested by the APA, would be to locate the pump station on the power plant side of the highway. However, the intake structure and associated pipeline could still cause conflicts.* Planning, design, and construction of components for a tailrace diversion will re- quire close coordination with all interested parties. Additionally, to enhance the reliability of this supply the APA should schedule any power plant maintenance shutdowns during the summer months when runoff from the Eklutna River and Thunderbird Creek is at maximum. Tunnel Diverting water from the tunnel offers the following advantages: 0 No pump stations 0 Continued water supply during hydroelectric facility shutdowns 0 Few moving parts Disadvantages include the following: 0 Purchase of lost hydroelectric facility generating capa- bility 0 Regulation of flow under varying heads 0 Difficult access to tunnel connection and penstocks for construction and maintenance 0 Difficult pipeline construction to the village of Eklutna 0 Possible effects on power plant operation 0 High-head pipe 0 Semi-remote water treatment' plant location at a high elevation 0 Construction of numerous pressure-reducing stations along the route for the various users *Verbal communication from Bob Cross, director of the APA, to Floyd Damron, CH2M HILL. December 1, 1981. 4-3 Eklutna Lake Based on optimum hydroelectric facility operations (rule curve), water may be diverted from the lake through the gate under the existing spillway for 4 months by gravity during an average water yea r. During the remaining 8 months, water could be diverted to the river by a low-lift pump station. Diverting water directly from Eklutna Lake to the Eklutna River has some advantages over diverting water from the tunnel: 0 No interference with the components of the Eklutna hy- droelectric facility 0 Less diversion of water or lost generating capability because of the additional water available from the river watershed 0 Less capital expenditures because 8 miles of pipeline, in difficult . terrain, between the power plant and the village of Eklutna would be eliminated 0 Staged construction potential The following are the principal disadvantages of an Eklutna Lake diversion: � Operation and maintenance costs of operating pump sta- tions at Eklutna Lake, the water treatment plant, and at Mirror Lake � Reduction of energy production at the power plant � Frazil ice could have a high impact on the intake facil- ity (this should be studied in more detail) Following a detailed analysis of the possible diversions during preliminary design, a lake tap may prove to be the most econom- ical and reliable method for diverting water from Eklutna Lake to the river. ASSUMPTIONS AND CRITERIA In developing alternatives for the Eklutna project, certain as- sumptions were made on the basis of information presented in the MAUS report, information supplied by the Municipality of Anchor- age and the APA, and field inspections of the proposed alterna- tive sites. In addition, criteria were used for the pipelines, pump stations, intake structures, and diversion dams to develop conceptual plans and to prepare order-of-magnitude cost estimates. For purposes of this initial evaluation, three alternatives were 4-4 developed that appear the most feasible. A detailed description of each alternative follows this section on assumptions and criteria. Water Demands It is assumed that the Eklutna diversion project would divert 70 mgd of water. Of this 70 mgd, 12.2 mgd would be available to the Eagle River-Eklutna area along the pipeline, and the remain- ing 57.8 mgd would be diverted to the Anchorage Bowl. Flow contributions for the Eagle River-Eklutna area were devel- oped for various points along the system by using population pro- jections presented in the report Eaqle River-Chugiak-Eklutna Comprehensive Plan prepared by AnER-orage Planning DepartmeFf and adopfe-dSeptember 13, 1979. The Comprehensive Plan di- vided the area between the Eagle River and the Eklutna River into seven subareas and assigned a Transportation Analysis Zone (TAZ) number to each. The 12.2 mgd was distributed along the route, based on the pro- portion of each subarea saturated population to the total saturated population. The flows distributed to each subarea are as follows: Design Saturation Su ba rea Flow (mgd) Flow (mgd) Eklutna (TAZ 417) 1.1 1.6 Peters Creek (TAZ 415) 3.5 4.7 Birchwood (TAZ 412) 2.7 3.7 Chugiak (TAZ 410) 1.0 1.4 Eagle River (TAZ 405) 1.5 2.1 N. Eagle River Valley (TAZ 408) - 1.8 2.5 S. Eagle River Valley (TAZ 400) -0.6 0.6 Tota 1 12.2 16.6 The approximate location of each point flow is shown on the plan and profile sheets (see Figures 4-3, 4-4, and 4-12 through 4-16). It should be emphasized that the location and size of each point flow is approximate and will vary as comprehensive water distri- bution master plans are developed for each community. Transmission Pipeline Conceptual plans developed for pipeline routes for each alternative extend from the point of diversion to the Eagle River. It is as- sumed that the remainder of the pipeline to the Municipal Water Treatment Plant in Anchorage would follow the route described in Appendix IV, Transmission Main Design. 4-5 Pipeline criteria and other considerations related to the pipeline are contained in Exhibit A of this report. Pump Stations Pump stations for the alternatives were assumed to have the fol- lowing characteristics: 0 Maximum plant efficiency of 70 percent 0 Metering and telemetry required 0 Surge control required for all pump stations 0 Eklutna Lake and tailrace pump stations will require pile-supported foundations 0 Staged construction of each station should be considered for final sizing of the station; for estimating purposes, an ultimate capacity of 70 mgd was assumed Intake Structures Intake structure features were assumed to be the following: 0 Trashracks required 0 Intake designed so that invert is minimum of 6 feet be- low low water elevation 0 Designed for ultimate flow of 70 mgd 0 Two-pipe barrels between intake and pump stations to allow for staged construction of pump stations 0 Stop logs and slide gates to facilitate cleaning of sediment Diversion Dams Any proposed diversion dam was assumed to have the following features for purpose of developing conceptual plans: 0 Weir-type low-head concrete dam 0 Spillway designed for maximum probable storm 0 Six-foot submergence of diversion pipe 0 Designed for maximum diversion of 70 mgd 4-6 0 Gravity flow from dam to water treatment plant 0 Gates at bottom of dam to pass sediment buildup Treatment Plants The conceptual size and type of any proposed treatment plant and the proposed treatment processes are described in Chapter 5. Only locations of treatment plants are included in descriptions of the alternatives. ALTERNATIVE 1: TAILRACE AND RIVER DIVERSION This alternative draws water from the hydroelectric project tail- race and from the Eklutna River. Early in the life of the pro- ject, a large percentage of the summer demand would be provided by the river flows. Later, as demands increased and during periods of low flow in the river, more water would be pumped from the tailrace. Components of this alternative include an intake structure and pump station located adjacent to the Eklutna power plant, a water treatment plant and pump station located at the Eklutna River, a diversion dam and gravity pipeline at the Eklutna River, a booster pump station between Mirror Lake and Peters Creek, and approximately 22 miles of pipeline between the power plant and the Eagle River. Treated water would be avail- able to communities along the line. A layout for this alternative for Alternatives 2 and 3 is shown on Figure 4-2. Transmission Pipeline The 54-inch transmission pipeline generally follows Glenn Highway from the Eklutna power plant to the Eagle River (Figures 4-3 and 4-4). The pipeline begins just south of the Eklutna power plant, with a diversion structure on the tailrace of the Eklutna power plant to divert water to the tailrace pump station. The first 18,000 feet of the pipeline parallels the eastern right-of-way of the Old Glenn Highway. From that point, the next 4,000 feet of pipeline parallels the Alaska Railroad. The pipeline then parallels the eastern right-of-way of Glenn Highway for 18,000 feet to the new water treatment plant (%VTP). The water is again pumped from the WTP in a pipeline paralleling Glenn Highway for 25,000 feet to Peters Creek. Between Mirror Lake and Peters Creek the pressure is boosted. From that point, the pipeline parallels the Old Glenn Highway for 35,000 feet to Eagle River Loop Road. It parallels the Eagle River Loop Road for 2,500 feet, then turns south for 5,500 feet to the Eagle River Road. The pipeline continues 2,750 feet along Eagle River Road to its inter- section with Eagle River Loop Road and then turns south 5,250 feet to the Eagle River. The pipeline route measures approximately 116,000 feet (21.97 miles) in length. It would cross the Eklutna River, Peters Creek, 4-7 the Eagle River, and several small creeks. It also requires two crossings of the Alaska Railroad. The route shown in the Eagle River area may be shortened by approximately 8,000 feet by fol- lowing Glenn Highway. This would require construction of a pipeline in the business area of the town of Eagle River and in the Chugiak State Park Campground. Tailrace Intake Structure and Pump St tion The site plan of the proposed tailrace intake structure and pump station is shown in Figure 4-5. The site location selected is ten- tative because of numerous unknowns. Also, a fish hatchery is scheduled to be constructed in 1982 in the area between Old Glenn Highway and the tailrace. The proposed tailrace intake structure will consist of a trash rack, two bays, and two 48-inch outlet pipes with slide gates. The construction of the intake structure within the tailrace may require the shutdown of the power plant so that a temporary diversion canal can be constructed around the construction site. Once the intake structure is completed, the power plant may have to be shut down again so that the tailrace can be restored to its original location. So that disruption of the hydroelectric facilities can be kept to a minimum, it is recommended the intake structure and piping within the tailrace cross section be constructed for the ultimate diversion of 70 mgd rather than in stages. For the purpose of comparing the cost of the alternatives, the pump station was assumed to have a capacity of 70 mgd. The proposed tailrace pump station consists of eight 350-hp pumps, four 150-hp pumps, flow meters, surge suppression equipment, controls, and telemetry. The concrete structure would be pile supported as shown on Figure 4-6. The construction of this pump station could be staged by constructing redundant stations, each with 35-mgd capacity. (Shown on Figures 4-5 and 4-6 as 11proposed" and "future" 35-mgd pump stations.) The total average annual pump station energy requirements and the maximum horsepower requirements for the years 1985 to 2012 are shown on Figure 4-7. The average annual power consumption is based on a tailrace water elevation of 25.0 and the maximum horsepower requirement is based on a minimum tailrace water ele- vation of 18.0. Eklutna River Water Treatment Plant and Pump Station The proposed water treatment plant would be located near the Eklutna River at an approximate elevation of 110 feet. 4-8 The associated pump station would pump water to Mirror Lake and would have an ultimate capacity of 70 mgd and a peak power re- quirement of approximately 8,500 hp. Figure 4-8 shows this sta- tion's energy and maximum horsepower requirements. Eklutna River Diversion Dam The Eklutna River diversion dam would be located immediately upstream of the Old Glenn Highway-Eklutna River Bridge. The dam would be a fixed-crest concrete structure that would provide 6 feet of submergence over the diversion pipeline. Gates would be installed in the structure for sediment sluicing. Water would gravity flow through a 48-inch-diameter outlet pipe to the intake of the water treatment plant, at an approximate ele- vation of 110 feet. The inlet of the pipe would be equipped with a trash rack. Mirror Lake Booster Pump Station Figure 4-9 is a plan view of the proposed Mirror Lake booster pump station. The structure for this station would be sized to accommodate the pumps, motors, and miscellaneous equipment to handle an ultimate flow of 65.4 mgd (4.6 mgd used upstream). Initially, only the pumps and motors required to handle the year 2000 flows would be installed. The annual energy requirements and maximum horsepower requirements for the years 1985 to 2012 are shown on Figure 4-10. The total annual energy requirements for Alternative 1, excluding the water treatment plant, are shown on Figure 4-11. ALTERNATIVE 2: TUNNEL DIVERSION In this alternative, water would be diverted upstream of the tur- bines from the pressurized Eklutna hydroelectric facility tunnel at the adit near the surge tank by means of a tunnel connection. All of the ultimate 70-mgd demand would be provided from this location. The water would be treated at a high-altitude treatment plant along Eklutna Lake Road and would flow by gravity to An- chorage through a 24.7-mile-long pipeline. Communities along the pipeline would take water through pressure-reducing valves. Transmission Pipeline Alternative 2, the tunnel diversion, would deliver water by grav- ity. Plan and profile drawings for the proposed route to the Eagle River are shown on Figures 4-12 and 4-13. The pipeline begins just east of the Eklutna power plant with a connection to the existing tunnel near the surge tank and adit tunnel. The first 1,400 feet of the 48-inch-diameter pipeline (penstock) would drop 650 feet in elevation to a point near the power plant. From 4-9 the power plant, a 60-inch pipeline would parallel the eastern right-of-way of the Old Glenn Highway 19,000 feet to the Alaska Railroad. The next 17,000 feet of the pipeline parallels the Alaska Railroad. The pipeline then would turn east paralleling the Eklutna Lake access road for 6,400 feet to a new water treat- ment plant, located at an approximate elevation of 650 feet. The water gravity flows from the WTP 7,500 feet along the Eklutna Lake access road to Glenn Highway. The pipeline would parallel Glenn Highway for 27,000 feet to Peters Creek. From that point, it would parallel the Old Glenn Highway for 36,000 feet to the Eagle River Loop Road. The pipeline then would parallel the Eagle River Loop Road for 2,500 feet where it turns south for 5,500 feet to Eagle River Road. It would continue 2,750 feet along Eagle River Road to its intersection with Eagle River Loop Road and then south 5,250 feet to the Eagle River. The pipeline route is 130,300 feet long (24.68 miles). The pipe- line will require three major water crossings, the Eklutna River, Peters Creek, and the Eagle River. It also requires two cross- ings of the Alaska Railroad. The pipeline will require up to 400-psi pipe because of high static and dynamic heads. Eklutna Tunnel Connection The proposed Eklutna tunnel connection would be made upstream of the existing surge tank. A short tunnel would be constructed from the existing adit tunnel to tap the tunnel. This would allow continued access to the Eklutna tunnel through the existing steel access door. The connection would require shutdown and dewat- ering of the tunnel during construction. This shutdown may re- move the tunnel from service for 5 to 10 days. The tunnel con- nection would have an automatic shutoff valve that would respond to a break in the pipeline, and the tunnel head gate should be automated as a backup. A number of options exist for making the actual connection to the tunnel; these options can be studied prior to design. This effort would require close coordination among the APA, the Municipality of Anchorage, and the design engineer. Eklutna Lake Water Treatment Plant The proposed water treatment plant would be located north of the Eklutna Lake Road at an approximate elevation of 650 feet. ALTERNATIVE 3: EKLUTNA LAKE AND RIVER DIVERSION This alternative would divert water directly from Eklutna Lake and the Eklutna River. Except for the Eklutna Lake dam, none of the existing hydroelectric project facilities would be affected. Early in the life of the project, a large percentage of the increas- ing demand would be provided by the river flows. Much of the winter low flows in the river would be required for minimum 4-10 streamflow maintenance downstream of the old diversion structure near the Old Glenn Highway. To meet demands not met by the river, water would be diverted into the river by opening the 30-inch by 30-inch gate in the existing Eklutna Lake dam. Com- ponents of this alternative would be a pump station and river discharge pipeline at Eklutna Lake, a diversion dam and gravity pipeline near the intersection of the Eklutna River and the Old Glenn Highway, a water treatment plant and pump station near the Eklutna River, a booster pump station between Mirror Lake and Peters Creek, and approximately 14.4 miles of pipeline be- tween Eklutna River and Eagle River. Treated water would be available to communities along the pipeline. Transmission Pipeline The 54-inch transmission pipeline generally follows the Old Glenn Highway from the Eklutna River diversion to the Eagle River (Figures 4-14, 4-15, and 4-16). Water from Eklutna Lake would be diverted by gravity into the Eklutna River, when possible, via a gate under the spillway and pumped to the river by a low-lift pump station when the lake is too low for gravity diversion. The diverted water would flow approximately 8 miles down the Eklutna River stream channel to the Eklutna River diversion dam de- scribed for Alternative 1. There it would be diverted from the river to the proposed water treatment plant. The water would then be pumped from the water treatment plant in a 54-inch pipe- line following the same route described for Alternative 1 to the Eagle River. The pipeline route measures -76,000 feet (14.39 miles) in length. It would cross the Eklutna River, Peters Creek, and the Eagle River. Two pump stations would be required to lift water from the diversion dam to hydraulic elevation 553 at the Eagle River. Eklutna Lake Pump Station Eklutna Lake water will be diverted only when required to sup- plement water available from the Eklutna River watershed below Eklutna La ke. During later summer and in the fall, water can be diverted by gravity through a gate in the existing dam. The invert in the gate is at an elevation of 852 feet. Once the lake drops to an elevation of 854 to 856 feet, the water would have to be pumped. A tentative site plan of the proposed pump station, diversion channel, and discharge pipeline is shown on Figure 4-17. The plan was devel 'oped solely for the purpose of preparing an order- of-magnitude cost estimate and for estimating the annual energy requirements. Components of this system would include the following: 4-11 0 2,000 lineal feet of intake channel 0 Pump station with a maximum power requirement of 1,000 hp at 70 mgd 0 Check dam to prevent backflow into the lake when water is being pumped from the lake to the existing dam and to reduce the amount of discharge piping required 0 Flow measuring station located downstream of the exist- ing dam The annual energy requirements and the maximum horsepower requirements for the pump station for the years 1985 to 2012 are depicted on Figure 4-18. Water Treatment, Diversion, and Pumping Facilities A description of the Eklutna River diversion and pumping facili- ties and the location of the treatment plant are presented in the detailed description of Alternative 1 in this chapter. The total annual energy requirements, excluding the water treatment plant, for Alternative 3 for the years 1985 to 2012 are shown on Figure 4-19. FURTHER CONSIDERATIONS Transmission Pipeline Routes It should be emphasized that the routes shown for each alterna- tive are general corridors and do not represent final alignments. Final alignment selection will reflect the results of meetings with the various agencies involved, detailed design, and a detailed analysis of costs and specific environmental constraints and utility conflicts. An alignment paralleling the Alaska Railroad should be considered during more detailed studies. Utilities Conflicts with existing gas, water, sewer, and electrical utilities are.not significant with any of the alternatives. The following types of utility problems will require solutions: 0 Protecting the proposed pipeline from existing cathodic protection systems 0 Separating the proposed water transmission main from existing sewers in accordance with Alaska State Health Department standards 4-12 0 Protecting existing utility poles and towers from over- turning 0 Protecting workmen from hazards associated with nearby high-voltage lines and natural gas mains 0 Maintaining the operation of existing utilities Easements and Permits Each alternative would require permits from the same agencies. However, because Alternative 3 would require construction in and around Eklutna Lake, which is part of Chugach State Park and a more environmentally sensitive area, permits may be more difficult to obtain. Alternative 2 would require the water treatment facility to be built in Chugach State Park and may present permitting difficulties. Three major water crossings would be required for all the alter- natives. All crossings will be scheduled with the Department of Fish and Game to minimize the risk to the fisheries and to reduce sedimentation. Public Interface Problems caused by noise, dust, traffic control, and interruption of public and governmental access are manageable for all routes. There would be temporary disruption of visitor facilities at Eklutna Lake during construction of Alternative 3, and some long- term visual impact would be incurred. This alternative, however, would make electricity available to several nearby residents and to campers because a new powerline is required for the lake pump station. Alternatives 1 and 2 would require more pipeline than Alternative 3 and would, therefore, have greater construction impact. Traffic control along the pipeline route during construction would be required for all alternatives. One-way traffic may be required during daytime construction at many places along the pipeline route. Normal two-way traffic flow would be restored after work- ing hours. Each alternative would require close coordination with the State of Alaska, Eklutna, Inc., Alaska Power Administration, the commu- nities north of Eagle River, and several Municipality of Anchorage departments. Operation, Maintenance, and Accessibility The transmission pipeline, like any other facility, requires routine and special maintenance. Routine maintenance primarily consists of inspection on a regularly scheduled basis. Items that should 4-13 be checked are blowoff air valves and pressure versus flow read- ings to determine if sediments are depositing in the pipeline. Should cathodic protection be necessary to prevent pipe corro- sion, a routine monitoring program would also be needed. Special maintenance consists of repairing leaks, cleaning the pipe- line if required (particularly during low initial flows), and repair- ing any special linings or coatings. For routine maintenance or special maintenance, the pipeline must be accessible. Alternative 1 would offer the best accessibility. Access to the tunnel connection and penstock of Alternative 2 would present some difficulties, but these would not be insur- mountable. Access to the Eklutna Lake pump station and river diversion facilities may present the most difficulties (Alternative 3). During the preliminary design phase, methods of providing access into the pipeline and provisions for dewatering the pipeline should be addressed. Blowoffs located in the sags of the pipeline and access manholes at convenient stations would allow direct visual as well as television inspection of the inside of the pipe. Geotechnical and Geological Considerations With each alternative, substantial geotechnical input will be neces- sary for pump station and treatment plant siting, pipeline routing, and foundation and earthwork design. Geologic hazard evalua- tions would include (1) seismicity evaluation, which must be done to establish the design parameters, and (2) evaluation of the seismically induced hazards of ground shaking, soil liquefaction, landspreading and cracking (lateral displacement of soil), land- sliding, fault rupture, tectonic subsidence, and soil consolidation. These hazards have occurred in the past and must be evaluated prior to construction of a project. Alternative I Some potentially severe geotechnical and geologic conditions near the diversion and pump station facilities need to be evaluated: 0 Very soft, recent sedimentary deposits where the Eklutna powerhouse ta i I race diversion must be constructed. 0 A tidal marsh consisting of soft organic and silty soils, which the intake pipes must cross. Landspreading and cracking is a potentially severe problem during seismic events. High groundwater may also occur. The poten- tial exists for Lake George breakouts to flood the site as in the past. 4-14 0 Slope stability, where the site is close to the mountain base. The best geologic maps available and the con- struction records from the Eklutna hydroelectric project indicate the Knik Fault Zone passes directly through the proposed site. As part of the site exploration, the exact location of this fault will have to be established and an evaluation made of the potential for fault rup- ture. The degree of acceptable risk from this hazard may differ substantially from that established in the 1950's for the Eklutna powerplant. The pipeline from the pump station to the treatment plant near the Eklutna River will be constructed mostly in coarse, granular soils along the base of the mountains; this should not require any special geotechnical considerations. Starting about 1 mile east of Glenn Highway, the route crosses tidal marsh areas with poten- tially severe landspreading and cracking, soil liquefaction, high ground water, and pipeline support problems. Discontinuous permafrost is present along portions of this alterna- tive from about 1 mile east of Glenn Highway to the proposed treatment plant. These portions will have to be located during the pipeline subsurface exploration. No special geotechnical conditions are involved at the proposed water treatment plant site. Normal foundation exploration and analysis will be sufficient. From the treatment plant to the Eagle River, ground conditions are generally good. Isolated areas of organic (peat) soil, soft silt and clay, or permafrost will be encountered. Some slope sta- bility and potential landspreading or cracking problems may be encountered at stream crossings, especially in recent alluvium. Alternative 2 Rock in the area of the tunnel east portal is described in the Eklutna project construction report as shattered or broken, iron- stained, and containing many fault gouge seams. This will be difficult rock through which to access the Eklutna tunnel, and the rock quality must be established through exploration and evaluation. Slope stability will have to be evaluated and any nec- essary mitigation measures designed for the pipeline route down to the toe of the mountain. Bedrock may be encountered in the northeast corner of Section 30, along the northwest- southeast trending sections that lead to the proposed water treatment plant. Thick peat deposits are also present along this section. The locations of these materials will have to be carefully determined for the pipeline design. 4-15 At the proposed water treatment plant site, 3 to 4 feet of peat is present in places. A thorough foundation exploration will be nec- essary at this site. Alternative 3 Intake Channel. Material around the edge of the lake is de- scribed i-n-t-Fe-Eklutna construction report as soupy and unconsol- idated sift. Cut slopes in this material for the pump station in- take channel will have to be 10:1 or flatter because of the low strength of this material. Deeper portions of this same cut may encounter dense clay and boulders that will be difficult to exca- va te. The use of sheet piling may prove advantageous. For the intake channel design, a difficult subsurface exploration will be necessary to determine the materials to be excavated and appro- priate cut slopes. Old Eklutna River Diversion Dam and Tunnel. A structural engi- neer, a geotechnical engineer, and an engineering geologist should examine the old dam to determine its condition. Stability analysis by the geotechnical engineer may be required. The geo- technical engineer and geologist should also examine any acces- sible portions of the tunnel. No special geotechnical conditions are known to exist at the pro- posed Eklutna River diversion site. The site should be evaluated for the use of sheet pile dam construction as well as other con- ventional designs. Optimization of Costs The three alternatives described can be'further refined to opti- mize their costs. A detailed study would evaluate staged con- struction of each physical component, alignment alternatives, cost of pipe size versus energy cost, and the use of the old Eklutna River diversion dam and tunnel. Staged Construction Methods of staging the project need to be thoroughly explored. Each pump station and the water treatment plant would be con- structed in stages. Phased construction of the pump stations could consist of building the station structures large enough to house the equipment for the ultimate flow, but initially installing only the pumps and motors for an interim flow. Another staging possibility would be to construct a station for the interim flow and construct an additional station when the capacity of the initial station is reached. It also may be advantageous to construct the water treatment plant pump station initially so that the interim flow can be lifted to Anchorage without requiring the Mirror Lake booster pump station. As demand increases and the capacity of the treatment plant pump station is reached, the booster pump station would be added. 4-16 Alignment Alternatives The alignment shown for each alternative is tentative. For ex- ample, in the Eagle River area a route was selected that would tie into the alignment of the Eagle River pipeline developed in Ap- pendix IV. A route through the business district of Eagle River and the Chugach State Park Campground would eliminate the need for constructing approximately 8,000 feet of pipe. Pipe Size Versus Energy As energy costs increase, the head loss caused by pipe friction needs to be more closely analyzed. For example, if the 54-inch pipe selected for Alternatives 1 and 3 were enlarged to 60 inches, head loss in the system could be reduced by approximately 100 feet. An economic analysis of energy saving versus the added cost of capital improvement will need to be performed. Old Eklutna River Diversion Dam and Tunnel The use of the old dam and tunnel on Eklutna River should be evaluated if Alternative 3 is further studied. The use of these facilities could reduce the system head requirements by approxi- mately 130 to 140 feet. 4-17 90,000 80 80,000 70 70,000 M 60 E z z 2 60,000 LU LLJ Q Iq 50 a LLJ LLI Uj 50,000 U.1 0 L) z z 40 1-- LLI LLI LU 40,000 LLJ 2 2 0 0 30 z 0 0 Cn F5 30,000 .,tAN RIVER AND CC LLI LU tva-0 > CREEK > a a cc cc LLI 20 LLI 20,000 10,000 10 0 0 1980 1990 2000 2010 2020 2030 YEAR NOTE: Time base assumes no additional supplies developed within the Anchorage Bowl. Figure 4-1 Annual Water Diversion 4-19 from Proposed Water Sources co t4 oil, 0 C> A, HIG141AIA ALTERNATIVE 1 c 0 (TAILRACE AND RIVER C r. C, 0 94t 5411 TAtLRACE A OA, 0 LEGEND 0 PROPOSED FACILITIES: 48" POWER m TAILRACE PUMP STATION PLANT POWER EKLUTNA RIVER DIVERSION DA rn TUNNEL TREATMENT PLANT AND PUMP rr) PIPELINE EKLUTNA LAKE 0 miles 5 4, ............. C, 0 HIGHwdv ALTERNATIVE 2 r 'i-tN (TUNNEL DIVERSION) 0, b 6%04, 4' T411-RA 6011 1 CE Go", 4, 1- LEGEND 48",/ 13 '1% PROPOSED FACILITIES: POWER m WATER TREATMENT PLANT PLANT TUNNEL DIVERSION TUNNEL PIPELINE rri EKLUTNA LAKE 0 Miles 5 co ALTERNATIVE 3 54@ 4, 0 (EKLUTNA LAKE AND "629A- @Q CO HIGHWAV RIVER DIVERSION) o LEGEND 04, 'p ek 54" 'ILRACE -Q,.l -A PROPOSED FACILITIES: A MIRROR LAKE BOOSTER PUMP POWER EKLUTNA LAKE PUMP STATION PLANT 48" POWER LINE TO PUMP STATION EKLUTNA RIVER DIVERSION DA TUNNEL ...... rn rn WATER TREATMENT PLANT AND PUMP STATION EKLUrNA 0 Mile 5 LAKE -PIPELINE 800+00 t N G TAZ A' 405 As -950+00 8%,4 ALTErATIVE 4 ROUTE 900+0 b, 0 4 V Ail, A A V1, eT, 0%0 TAZ 400 0.6 mgd V, +0 600 0 A; 800- ......... ... ...... ..... ....... .... . .... ........... ... ........... . ................... ........ .......................... ..... .......... .............. ...... . .. .... ... . ................ .. .................... ...... ........ ........... ............ ........... .................. .... . .......... ........... .. ............. ........... ......... ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LINE, (Ht . . . . . . . . . . . . . . . HYDRAULItGRADE ............ MG. ........ .. ............ ....... ... ....... ... ...... ...... .................. ................. .. ........ ...................... ... ........... .............. .............. .......... ..................... .................................... ...... ...... ......... uj /* . . . . . . . . . . . . . . . . .......... ........... ................. ............... ........ . . ................ .. ...... .......... ............................... ........................... ........... . ........ ...................... ............................ ...... . . ..... .. ...... ..... Cl Lu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -Wo .. ...... .............. ....... ....... .............. ............ ................... ............... ................. ........... ...... .. ......................... ............................... .......... ......... ................ .......... .......................... . ............... .......... ....................................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8,900'.- 54" -5;200' 5V I 1,10W - .54". . . . . . . . . . . . . . . 58.4 mgd. -60.2rngd. . . . . . . . . . . . . . 6t7-mgc! . . . . . . 62.7 mgd-'- . . . . . . . . . . . . . . . . . ...... ...... ...... ..... . ......... ... ......... ......... ......... .......... rsoo-ioo . . . . . . . . . 700+00 . . . . . . 800-@oo . . . . . . . goo-loo' . . . 100 ..... ......... ......... ......... ......... . . . . . . . . . . . . . . STATION - I wo+oo PROPOSE WATER TREATMFNtl: PLA AND ob ION' PROPOSED DIVERSION DAM & PIPELINE 7- 1300+00 T 41 4;oo ' v@ 114 K@ 1. 34 's owl 71@ 5+00 ............. BOG ........ ........................ .......................... ................ ............ ............................. ......................... ....................................... .................................... ... ................... ............... .......................... .. ..................... ................ .................. .......... ........................ ....................................... ....................................... ....................................... ......... ......................... ............. ........... .......... .......... ...................... ...... ................................ ....................................... ........................ ....................................... ....... ..... .. I ...... ...... ................ .:.z ....... .......... ......... ......... ......... . . . . . . . . . . . . . . . . . w . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 . . . . . . . . . . . . . . LU 0 . . . . . . . . . . . . . . . . . . . . . . . . . f: ... 460 ......... .................... cc ................................. ....................................... .................. ............ . ...................... ........ ........................... .... ....................................... ....................................... ....................................... ................................... ................ ..................... ......... ....... ui . . ..... ..... .. ......... > . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 'o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _j . . . . . . . . . . . . . . . . . . . . . . . . LU 1110 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............. 40 ......... ........................ ....................................... ....................................... ....... ................... ....... .... ................................. ................................. ............ .......................... ........ .................... ....................................... ....................................... ................................ . ......... . . . . . . . . . . . HG.L . ......... ....... ......... .... ....... ............... ........ ......... ............. ........... ................................... .................. ...... ................... ........................................................... .................... ............ ....................................... ........ .............................. ........... ........... .................. 4t7oW.- ......... .... ................. . . . 68;9-mgd 70-mgd 12154,00 . . . . . . . . . ....... .... .... ... ......... .... . . . . . . . 13W4W . . . . . . 200OW . . . . . . . . 1400+W . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . @tktlON PROPOSED C FISH HATCHERY @SITE INTAKE STRUCTURE 54" 0 PIPELINE FUTURE 35-mgd OLO PUMP STATION PROPOSED 35-mgd PUMP STATION ALTERNATI E PUMP STATION SITE EXISTI NG EKLUTNA POWER PLANT PENSTOCK TUNNEL 250 50 100 150 200 - - ---A SCALE - FEET NOTE: Assumes construction of pump station in two 35-mgd stages. Figure 4-5 Tailrace Int and Pump Site Plan ff III II SMAL LARGE UNITS UNITS EL. 37.0 DISCHARGE HEADER WALL SUPP EL. 12. SECTION PROPOSED 35-mgd PUMP STATION 48"0 54")( BURIED DISCHARGE HEADER n il n nj_ FU FUTURE 35-mgd PUMP STATION Li I r Lj Not to Scale PLAN NOTE: Assumes construction of pump station in two 35-mgd stages. Figure 4-6 Tailrace Pump Station 0- D' HI Plan and Section 4-28 16,000- 14,000- 12,000, 10,000- W > X 0 cc 4,000 0. LU 8,000- LU z Cn LU 4/ 0: 0 6,000- 0 -3,000 4,000- -2,000 2,000- 1,000 0 1980 1990 2000 2010 2020 2030 YEAR NOTE: Time base assumes no additional supplies developed within the Anchorage Bowl. Figure 4-7 Tailrace Pump Station Annual Energy and 4-29 Maximum Power Requirements 60,000- 50,000- -10,000 40,000- - 8,000 LU X 0 CL LU LU z LLJ 0 30,000- -6,000 X 20,000- 4,000 10,000- 2,000 1980 1990 2000 2010 2020 2030 YEAR NOTE: Time base assumes no additional supplies developed within the Anchorage Bowl. ____j I Figure 4-8 Eklutna River Water Treatment Plant Pump Station 4-30 Annual Energy and Maximum Power Requirements TO EAGLE RIVER TO EKLUTNA OLD GLENN HIGHWAY 54"OPIPELINE 54-0 PIPELINE PHASE 1 - ----- DISCHARGE PUMPS PIPING z (TYP.) 42"0 LLI a FUTURE PUMPS 1-:ij IS. I-L-Zjj (TYP.) x X -\A Not to Scale Figure 4-9 Mirror Lake Booster z Pump Station Plan View 30,000 - 24,000 20,000 - 16,000 - 4,000 CC LLJ 0 X a- CC LU W W z LU 0 12,000 - 3,000 8,000 - 2,000 4,000 - 1,000 1 0 1990 2000 2010 2020 2030 NOTE: Time base assumes no additional supplies YEAR developed within the Anchorage Bowl. Figure 4-10 Mirror Lake Booster Pump Station Annual Energy and Maximum Power Requirements 4-32 120,000- 100,000- -20,000 LU 80,000- -16,000 @: CD 0 CIL CC X UJI LLJ Co Cr. 0 X 60,000- -12,000 40,000- - 8,000 20,000- - 4,000 1980 1990 2000 2010 2020 2030 YEAR NOTE: Time base assumes no additional supplies developed within the Anchorage Bowl. Figure 4-11 Alternative 1 Total Annual Energy and Maximum Power Requirements (Excluding Water Treatment Plant) 4-33 800+00 U P F % 4 % 4 50+00 A T 41 4-00/ '2 41 4 050tQ0 Y % x TAZ .460 mod" 04 606+00 -@e V 4, "v, so* ................................. ........... ........................... ....................................... ...................................... ............................ .................. .................... ....................................... ............................. ............. ................ ............... . . . . . . . . . . . . . . . . ........................ ................ ........... ........ .... . ...... ........ ................... .... ..... ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....... ....... . . . . . . . . . . . . . . . . . ........... ................... ............ .......................... ................................ ... ........................ .......... 'HYDRAULIC GRADE LINE (HGL) . . . . . . . ................ .................... . ...... ............. -.. .................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...... ...................... .......... ........ cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . w ........ .. ...... ........ cc . . . . . . . . . . . . . . . . . . . . . . . uj z ........ ..... . . . . .. . . . . ........... ........... ................... . . . . . . . . . . . . . . . . . .......................................: N . . . . . . I . . : ..... ..... ... . ................. .. ................................... .................................. .......... ............................ .................................... ...................... .... ................. ............. ....................................... 7@ LLJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...... ....... . . . . . . . . . . . . . . . F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................ . . . . . . . . . . . . . . . . 200 .. ........ . . . . . . . ........... ................. .................. ................. . : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............... .......... .. ............................ ....................................... .......... ........................... .............. ........................ . ................. ................... ....................................... ....................................... .. ...... ......... ...... ........ ......... ......... ..... ... ........ ...... .......... ......... ...... ....... ...... I, 100, 60'@ . . . . . . . . . . . . . . .. oo,.:6.0 .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89 1 1 1 58.4.mgd . . . . . . . . . . . . . . . . . . 7,000'@ 60 ... . . . . .......... M2 mgd . . . . . . . . . . . . . . . . . . . . . . . 16,500'. - 60 ... . . . . . . . . . . 6.1.7 mid . . . . . . . . . .62,7 lp 6.0 @Mgd . . . . . . . . . . . . . . . . . . . . . 64.0 F.:ngd - 0' . . . . . . . . . . ...... ...... 600@00 - . . . . . . . . . . . . 700+00, . . . . . . . . . . . . . . . . . . . . 800@00 . . . . . . . . . . . . . . . . . 900+00. . . . . . . . . . . . . . . . . . . . . . loob+oo . . . . . . . ...... ........ 'STATION 1700+00 1600+00 +00 f5 1500+00" PROPOSED WAtER TAZ TREATMENT PLAhiT, 1300+00 417 MOO)' @4 4000,, ............. ......................... ....................................... ........................ .............. ....................................... ... ............................. .......................... ........... ....................................... ........ .............................. ........... ....... .................. ................ .......... .................... + Xr ...... .... ........... ......... . .......... ........ ......... ........ ........ ........ ............. ......................... ....................................... ....................................... ................................. .... ... .............................. ......................... ............ ................ ....... ........ .................. . ...................................... ............ ................. .... ..... .............................. .......... :+@ ...... ......... ....... ......... ....... ..... ..... ........ 0 ......... .... ........ ......... p ... 400+.:: ............. ......... ............... ................................ ....................................... ................................. . .......................... ............................... ....................................... ........ ....................... ........... ....... . ................ .............................. ..................................... Ic . . . . . . . . > :: . . . . . . . . . . . . . . . . .......... ........ ........ . . . . . . . . . . . LU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...... ..... ....................................... ......... .... ........ .... ... ...... .......... ............ ............. ... ......... ............... ....................... ........ ,/ .... ............. ........................ ............ ........ .................. ........... I............... .......... ........................ 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UM 17 STATUION' . . . . . . . . . :: . . . . . . . . . 00+00 R r T 4 5 A 1.5 d, 1.0 mgd --950+00 @W, T 8 ALTEMA'11@ t +00 ROUTE 4 IV 900too ,,,I -oo X 056 ve, N@q wffi4d- TAZ 00+06 0 6.6 mgd 50+ 06, Z, 4A 60 00 800 .. .................. .................... ................................ ....................................... ....... ............................... ....................................... ....................................... ....................................... ....................................... ....................................... ....................................... ....................................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HYDRAULI@ GRADE-LINE-fHQ J . . . . . . . . . . . . . . . . . . . .. ..... ......... ......... 60G . .............. ...... ................. ............ ........................... ....................................... . .................................... ....................................... .......................................... .......... ........................... ....................................... ................... ...................... .................................... ..... ....... . ......... ......... .. ...... ......... ......... ......... ...... ......... ..... ......... ..... .. ...... > . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - ...... 4OG- .......... ........................... ....................................... ................. .................. .. ............................... ................................... ......... ........ ... ................................... . ...... .............................. ................................... .......................................... . . . . . . . ..... lu . . . . . . . . . . . . . . . . . . . . . . . . . . Lu ......... ...... ......... ......... ....... ......... ......... ......... ...... ......... ............................... .......... ........................... ....................................... ....................................... .................................... ....................................... .......... .......... ............. ....................................... . ................... ......... ............ ....................................... .. ................ ......... ......... ........ 6,200! 54'! .11,100'.- 54" . . . . . . . . . . . . . . . . . 8,900' 54!* - . . . . 7,000- 54 ... . . . . . . . . . . . . . . . . . . . . . 16,500' - 54" . . . 58.4 m9d - L .60.2 m9d . . . . . . . . . . . . . . . . . . . . 61.7 mgd - 62.7 mgd . . . . . . . . . . . . . . . . . . . 64.0- mgd . . . . . .......... G- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700+00 . . . . . . 800+00 . . . . . . . . . . . . . . . . . . . . . . . . . . 600+00. . . . . . . . . . soo+Go - 1000+00 X'N) K PROPOSED WATER" P 'ANT AND" P STATIM 7 @7 BEGIN, A PROPOSED,- - @"POWERLI NE PROPOSED DIVE RSI ON-DA4"l & PIPELINE POWEJF PROPOSED _(LINE TO Ek LUTNA, LAKE TAZ 417 1,300+00 .1 Tgd AQ 0@ 2" "_,Q o 7" @4,()o 0 l +04 i 6+00 ........ ......................... ....................................... ....................................... ....................................... .... .................................. ....................................... ....................................... ....................................... ............................. ............................ .......... ....................................... Soo-: ............ ......................... ....................................... ....................................... .................... .................. .................. ....................................... ............. ...................... ............. ......................... .................................... ............................ ...... ... .. .......... . ...................... ......... ....... ......... ... ......... ......... .. . . . . . . . . . . . . . . . . . . . . . . . . . . uj 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .......... ........................ ............... ..................... ....................................... ............................... . ........... ........ .... .......... ............ ....................................... ................. ..................... ....................................... ....................................... . . . . LU . ............................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ui . . . . . . . . . . . . . . . A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . uj ....... ......... Lu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......... ... ....... .0c) ...... ......... ......... . ....... ...... . . . . . . . . . . . . . . . . 00 . . . . . . .......... ...... .. ......... ...... ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . ui 0.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-:: ............ ......................... ..................................... ............ .... ..... ... ..... .............I ....... ....................................... ........ ............... ....................................... ....................................... ....................................... ...................................... ........... ......... . . . . . . . . . . . . . . . . . . . . . . . . . ......... ...... ...... ........ ......... .......... ....... ..... ... ..........o .. ......................... ................................... 14;0001-54!!@ .................. ............................... ...... ....................................... ....................................... ....................................... ....................................... ....................................... ............................ .......... '11-2170"'W"" . . . . . . . . . . . . . . . 69.9 rvlgd 70 inbd . . . . . . . . . . ......... ......... ......... ......... .1215+00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .......... ........... .............. ......... ......... ......... ......... ......... ......... ......... 1200+QQ . . . . . I:ioo+QQ STATION B`E0IN /PAOPOSED P WERLINE 'PROP OiEDY- zJ00M. NN., PROPOSED A- IWATER TREATME, fPLANT A BANDONED. EKLUTIYA, D IVERSJON DAM & TUNNit PR OSED DI RSION DA & PIPEL@@E'- TAZ 4 17 1.1 moo VA /Ir ............... .............................................. ................................ ....................................... ....................................... ....................................... ........... ........ .................. ....................................... ....................................... ....................................... ....................................... ...................................... .......... ......... ........ ........ ......... ......... ....... . ......... ......... ......... ......... .. ............... ......... ......... ......... ......... ....... ......... ......... ......... ........... ......... .................. . ....... ......... ............... ......... ....... . ....... . ......... ...... ...... . ............. ....... ......... ......... ......... ...... ............... ....................................... ................................. .................................... ....................................... .................................. ....................................... ....................................... ....................................... ....................................... ....................................... ...................................... .......... a ......... ......... ......... .......... ......... . ..... ......... ......... ......... ......... . ....... .......... ......... ........ ......... ......... ......... ......... .................... ... ... .. .. ... ......... ......... ... .... ..... . . .......... ......... .... .. ......... ......... ....... . ....... ......................................................................... ....................................... ....................................... ....................................... ....................................... ....................................... ....................................... ............. ......................... ....................................... ...................................... .......................... ................... ........ ......... ...... .. ......... ......... .......... ......... ....... . ...... ........ ......... .................... ....... ... ..... ... . ........ ....... .. ...... ............ ...... . . ... ...... ......... . ................. ....... ... ..... ......... ......... . .............. ......... ...... .................. ............. ..................................... ...... ............................. ....................................... ....................................... ....................................... ............. ......................... ....................................... ....................................... .......................... ........... .... ............. .. .... ......... ......... .............. .... ...... ..... . ......... ......... ... .... ... ..... .... ...... ... ... ....... . ......... ........ ......... ............... ... ....... ...... ......... ......... ......... . ............... ........ .... .... ........ ......... ......... ......... ......... ........... ......... ...... ......... ........... .................... .................. ............................. ....................................... .........................-.... ................... ............... ....................................... ................... ................... ............................ ....................... ........... ......... .......... ................. ...................................... ............... . ...... ......... ......... ......... ......... IN% IEL 2 EXISTING ROAD ACCESS ROAD - 12'WIDTH PROPOSED POW INVERT 0:1 SL TRANSMISSION LINE E R ELEV. 810.0 PROPOSED EKLUTNA LAKE P.S. PAD ELEV. 885� INTAKE CHANNEL Un A3 48".0 DISCHARGE PIPE I "=400t EXISTING DAM It CREST 871.0 DIVERSION DAM OUTLET OF 30"x3O" I @; @Z4 SLIDEGATE w/GATE (ELEV. 852.0) TOP ELEV. 858t Figure 4-17 Eklutna Lak Site Plan 1400- 1400 1200- -1200 1000- 449 -1000 CO 800- 800 X 0 z A. W W 0 600- 600 400- 400 200 200 0 0 1980 1990 2000 2010 2020 2030 NOTE: Time base assumes no additional supplies YEAR developed within the Anchorage Bowl. Figure 4-18 Eklutna Lake Pump Station Annual Energy and 4-46 Maximum Power Requirements 100,000 20,000 80,000 16,000 0 0 Cr X Ar- LU LU z 0 60,000 12,000 a. R: W Z@S Ca cc 0 A 40,000 8,000 20,000 4,000 V- 1980 iggo 2000 2010 2020 2030 YEAR NOTE: Time base assumes no additional supplies developed within the Anchorage Bowl. Figure 4-19 Alternative 3 Total Annual Energy and Maximum Power Requirements (Excluding Water Treatment Plant) 4-47 Chapter 5 WATER QUALITY AND TREATABILITY The objective of this chapter is to present both our investigation of the suitability of Eklutna Lake water as a potable water sup- ply source and our comparison of Eklutna water and Eagle River water. The purpose of the comparison is to determine the need for treatment processes different from those proposed for Eagle River. This chapter is intended to complement the MAUS and to augment water quality data collected by the United States Geolog- ical Survey (USGS) between 1948 and 1973. This chapter summarizes the USGS water quality data; presents the results and evaluation of field and laboratory tests; identi- fies treatment criteria and the best treatment processes for both the summer glacial melt period and the winter clear water period; and presents estimated project and annual operation and mainte- nance costs for a treatment plant suitable for operating the rec- ommended processes. DATA COLLECTION AND EVALUATION Water samples were collected during a 5-week period from the last week in September through October 1981. During this period data were gathered regularly and observations were made of var- iations in Eklutna Lake water quality. Because of the short study period, only a limited amount of new water quality data could be gathered. Some reliance has therefore been placed on the USGS water quality data. USGS Water Quality Data Water quality data collected by the USGS between 1948 and 1973 are included in Exhibit B to this appendix. Water was sampled from six different points along Eklutna Lake and the streams be- low the lake (Figure 5-1): 0 Five Mile Creek at Eklutna Lake 0 Three Mile Creek at Eklutna Lake 0 Eklutna River at Glenn Highway 0 Eklutna Creek near Palmer 0 Eklutna Creek below Eklutna Diversion Dam 0 Eklutna River below the hydroelectric facility These data are summarized in Table 5-1. The USGS data for the sampling point below the hydroelectric facility are most applicable to this study because they represent water from essentially the same source as that sampled in September.and October 1981 in the power plant. The water represented by the USGS data does con- tain contaminants (very small quantity) from the floor drains of the power plant, however. 5-1 AIM EKLUTNA RIVER EALUTNA POW BELOW POWER Pl. PLANT Old EKLUTNA RIVER Diversion Dam AT GLENN HWY EKLUTNA TUNNEL '10 EKLUTNA CRE K BELOW EKLUT A DIVERSION DAM Dam THREE EKLUTNA CREEK AT EK NEARPALMER Ln SCALE IN MILES 4F, 0 1 2 3 4 5 6 0k, SOURCE: U.S. Corps of Engineers. 1979. Figure 5-1 USGS Water Sampling Po Table 5-1 COMPARISON OF EAGLE RIVER AND VARIOUS EKLUTNA WATER QUALITIES Eklutna Water Sept. to Below Hydra Oct. 1980 Parameter Eagle R 5-Mile 3-Mile Glenn Hwy Near Palmer- Below Dam Facility Powerhouse Temp (OC) 3-8 -- -- ?-11.5 0-13 ?-11. 5 0-12.5 8-9 Ca (mg/1) 11-21 30 34 23 19(16-21) 16-24 18-25 3.0-3.1 Fe (mgjl) .4-4.6 -- -- .03 .01-.11 .01-.11 .01-.11 .41-.9 Mn (mg1J) .04-.08 .01-.12 .01- .05 Silica (mg/1) 2.7-30.9 5.9 6.7 4.3-4.9 3(2.3-6.4) 1.9-8.7 2.6-6.3 3-3.1 Nitrate-N(mg/1) .26(.1-.67) .32 .38 .16-.27 '.15 .6-.7 .11 .2-.37 Sulfate (mg/1) .5-38 30 30 18-19 16(13-35) 14-20 13-20 10 TDS (mg/1) 71-137(41-167) 135 159 94 75(64-86) 71-100 71-88 104-105 Turbidity (NTU) 5-400 26-30 Suspended Solids (mg/1) 6.4-400 3-20 4.3-5.6 Hardness CaCO 3 (mg / 1) 34-134 114 138 77-79 60(50-74) 65(51-93) 60(57-74) 56-61 Hardness Noncarb (mg/1) 43-78 24 23 15-16 15(9-18) 14(3-20) 11(7-19) -- Alkalinity as CaCO (mg1l) 44 90 115 62-63 45 55 50 43-46 Uj HCO 3(mg/1) 52 110 140 76-77 55(46-110) 65 60 -- CO 3 3(mg/1) 0 0 0 0 0 0 0 -- Conductivity 100(84-165) 219 264 161-167 130(107-214) 140(112-187) 130(120-144) 103-110 (umhos) Color (cu) jO(10-70) 10 10 5 5-10 5 10(3-30) 25-55 Cl (mg/1) 0 0 1-1.4 .4-2.5 .5-5.8 .9-3.4 1-1.0 Coliform (cols/100 ml) 80-817 0 Arsenic (mg1l) .001 .01 Ba (mg/1) .1 .5 Cd (mg/1) .002 .01 Cr (mg/1) 0 .01- .05 F (mg1l) 0-.2 o-.3 .1-1.0 .1 Pb (mg / 1) .002 .01 Hg (mg/1) .011 - Se (mg/1) .001 0.01 Ag (mg/1) 0 .01- .05 Na (mg / 1) 3.6 4.5 2.5-3.4 1.8 2.1-2.7 2.5-3.0 2-2.1 M g (mg/1) 9.1 12 4.7-5.2 2.4-3.9 2.8-5.6 2.7-3.2 -- K (mg/1) 1.0 .9 1.1-5.8 0.6-7.5 .2-.6 Cu (mg 1) .011 Zn (mg f) .05 pH (mg1l) 6.4-8.1 7.4 7.7 6.8-6.9 7.2(6.6-7.7) 7.3(7.0-7.8) 7.8(7.5-8.1) 7.5-7.7 C 0 2 (mg / 1) 7.0 4.5 15-20 5(2-20) 5(1.6-12) 2(.9-3.3) Source: USUS Water Quality Data, 1948-1973 Sampling Location All samples for testing done in September and October 1981 were collected from a sampling tap off the piping just upstream of the turbine inside the Eklutna power plant. This water is piped from Eklutna Lake through the 5-mile-long tunnel and penstock to the power plant, and is withdrawn from the downstream end of the Lake at approximately elevation 800, 70 feet below the full lake level. Water quality at this point should be relatively constant throughout the year. This sampling site was readily accessible and provided a convenient location to perform jar testing and take other field measurements of water quality. Equipment Equipment used for on-site testing included a four- and six- paddle stirrer, a Hach Model DREL turbidimeter, and a pH meter. Tests Tests performed at the sampling point included temperature, pH, and turbidity. Jar testing was performed to determine optimum coagulant dosage, effects of rapid and slow mixing, and floc set- tling rate. Testing was done weekly. In addition to on-site testing, samples were collected and trans- ported to an off-site laboratory for routine chemical and physical analyses. These tests were performed three times during the testing period. No particle size analysis was done. One sample was tested for radioactivity. The testing started on Septem- ber 29, 1981, and continued through October 30. Temperature No air or surface water temperature measurements were made at Eklutna Lake during the September to October 1981 sampling per- iod. Water temperature at the penstock sampling point in the power plant held fairly constant at 8 to 9 degrees centigrade (C). Powerhouse records indicate that average winter temperature of water in the penstock is 4 degrees C. As air temperature drop- ped through the month of October, it was observed that the color and turbidity of Eklutna Lake began to improve slightly. Turbidity Table 5-2 shows turbidity of water from the powerhouse ranging from approximately 26 NTU* to 30 NTU. Turbidity at the outlet end of Eklutna Lake is probably linked to air temperature and rate of melt of the glaciers feeding the lake, but the sampling period was not long enough to confirm this. The lake appears *NepheloF@'etric Turbidity Unit, a measurement of turbidity. 5-4 light greyish to green in color, which is typical of the rock flour solids that create the turbidity. Several parameters in Table 5-1 suggest that turbidity in the lake is lower at the outlet end, and possibly more constant. The USCS data contain direct measure- ments of turbidity only for the sampling point below the hydro- electric facility. There, turbidity does change over the year in response to glacial melt. Table 5-2 FIELD TEST QUALITY RESULTS 1981 Parameter Sept 29 Oct 5 Oct 9 Oct 16 Oct 23 Oct 29 Temp (1C) 9 8 9 8 8 8 Turbidity (NTU) 30 30 30 30 26, 28 26 pH 7.7 7.5 7.6 7.65 7.6 7.6 Samples were analyzed for both dissolved and suspended solids. Results are shown in Table 5-3. The rough correlation between turbidity and suspended solids demonstrated for Eagle River in Appendix III was also found in this study, with turbidity ranging from 1.1 to 1.5 times suspended solids in the colder months to 3 times the suspended solids during the glacial melt season. As shown in Table 5-1, dissolved solids measured at the powerhouse are less than those found at Five Mile and Three Mile Creeks, but more than those downstream of the dam. Suspended solids par- ticles that cause turbidity were not analyzed for size distribution. The data from tests taken during our testing period resemble the USGS data. Suspended solids measurements and turbidity gener- ally agree with historic data. pH The pH of Eklutna Lake water varies between 7.0 and 7.8. This information is tabulated in Tables 5-1 and 5-2. Alkalinity and Hardness According to the USGS data (Table 5-1) alkalinity and hardness appear to be relatively constant for a given location in the lake and seem to correlate with turbidity. Both alkalinity and hard- ness decrease downstream of Three Mile and Five Mile Creeks. Alkalinity varies from 45 to 60 mg1l; hardness varies from 60 to 90 mg/l. Both alkalinity and hardness are expressed in milli- grams per liter as CaCO 3 (see Tables 5-1 and 5-3). The higher 5-5 Table 5-3 LABORATORY TEST QUALITY RESULTS 1981 Parameter @ept 29 Oct 6 Oct 9 Oct 16---6`ct23 Ca (mg1l) 18 18 19 Fe (mg1l) 0.9 0.41 0.65 Mn (mg1I) 0.02 0.01 0.05 Si/SiO 2 (mg/1) 3.1 2.8 3.u Nitrate-N (mg/1) 0.37 0.20 0.23 Sulfate (mg/1) 10 12 10 TDS (mg/1) 105 65 104 Suspended solids (mg/1) 4.3 5.6 4.3 Hardness CaCO 3 59 56 61 (mg/1) Alkalinity as CaCO 3 43 46 44 Conductivity (umhos) 110 103 110 Color (cu) 55 25 40 Chloride (mg/1) 1 1 1.0 Coliform (cols/100 ml) 0 0 0 As (mg / 1) 0.01 0.01 Ba (mg / 1) 0.5 0.5 Cd (mg / 1) 0.010 0.010 C@ (mg/1) 0.01 0.05 F (mg/I 0.10 0.10 Pb (mg / 1) 0.01 0.01 Hg (mg1l) 0.001 0.001 Se (mg1l) 0.01 0.01 Ag (mg 1) 0.05 0.01 Na (mg 1) 2.0 2.1 Organics Endrin (mg 1) 0.0002 0.0002 Lindane (mg/1) 0.004 0.004 Methoxychlor (mg/1) 0.1 0.1 Toxaphene (mg/1) 0.005 0.005 2,4-D (mg/1) 0.1 0.1 2,4,5-TP Silvex 0.01 0.01 (mg/1) Radionuclides Gross Alpha Particle (pCi/l) 0. 6 � 0. 7 Gross Beta Particle (pCi/l) 4. 5 � 5.6 5-6 level of hardness (approximately 150 mg/1) reported in the MAUS report are not indicated in the USGS data nor by our laboratory tests. I ron and Color According to the USGS data (Table 5-1 and Exhibit B), iron and color content appear to be less, on the average, at all USGS sampling points than at the power plant. Also, both iron and color are higher than the EPA treatment goals only during the glacial melt period. Jar Testing Jar testing is a bench-scale test used to give coagulation and settling insight into full-scale processes. The primary purpose of jar testing in this task was to determine how different coagulant (alum) dosages react over the range of raw water quality sampled from the powerhouse. When the optimum alum dosage was deter- mined, other parameters were investigated to refine further the treatment requirements of Eklutna Lake water. Those parameters included the effects of rapid and slow mixing rates and of the duration of mixing. As in Eagle River water testing, initial jar testing of Eklutna Lake water showed that two separate alum dosages achieved coagulation and clarification within a broad range of alum dosage. Figure 5-2 shows alum dosage plotted against turbidity after mixing and set- tling. The plot shows four distinct zones that occur frequently in treating 'highly turbid water. From left to right, the zones can be described as follows: (1) insufficient alum, thus no co- agulation; (2) effective alum dosage, which achieves coagulation- clarification through destabilization of turbidity particles; (3) another zone of ineffective coagulation; and (4) a second zone of effective coagulation-clarification, this time resulting from adsorp- tion and enmeshment of turbidity particles. Plant-scale operation would use Zone 2 rather than Zone 4 for alum dosage since less chemical is used and a reduced volume of sludge is produced. Subsequent testing focused on this lower dosage zone to establish how dosage requirements varied with changing lake turbidity and temperature. 'Over the 5-week test period, raw water turbidity varied only slightly, from 26 to 30 NTU, and raw water temperature was nearly constant at 80 to 90C. No significant change in alum dosage was required. The optimum alum dosage for the test program was between 10 and 15 mg/l. The jar testing results showed that turbidity can be removed ef- fectively through use of coagulation, flocculation, and sedimenta- tion. The settled water produced from these procedures has a turbidity of 10 NTU or less. Figure 5-3 shows a typical plot of alum dosage against turbidity after settling. 5-7 ZONE I ZONE 2 ZONE 3 ZONE 4 100 Coagulation Region Lu cc 0 ALUM DOSAGE Figure 5-2 Coagulation of Water With High Turbidity 50 0 T 9' C; RAW WATER TURB. 30 NTU 4 MIN. @ 80 RPM >- 15 MIN. @ 25 RPM 20 MIN. SETTLING TIME 30 Fa cc cc LLJ F- 20 LLJ 10 0 10 26 30 40 50 60 ALUM DOSAGE (nng 1) Figure 5-3 1 5-8 Settled Water Turbidity vs Alum Dosage No testing was done to determine the effect of warming the water. Temperature variation tests on Eagle River water indicated little change in treated water quality. There is only a slight possibil- ity that lake water could be preheated as it enters the treatment plant by waste heat energy from another source. Additional testing established, in a general sense, the effect of varying either or both rapid mixing and slow mixing on floc for- mation and settling characteristics. Rapid mixing worked best with the stirrer set at 80 to 90 rpm for 3 to 4 minutes, and the slow mixing appeared to be most effective at 30 to 40 rpm for 12 to 15 minutes. Using optimum rapid and slow mixing, the best observed settled water characteristics resulted after 20 to 25 min- utes. No attempt was made to correlate the jar stirrer with plant-scale mixing equipment. Figure 5-4 illustrates the typical relationship between settled water turbidity and settling time. Because the alum dosage requirement was so low, the testing per- iod was short, and the results using alum with Eklutna Lake and Eagle River water were similar, no testing was done using poly- mers as a substitute coagulant or as a coagulant aid. It was observed that coagulation using 10 to 15 mg/I of alum re- sulted in a small decrease in pH from 7.5 to 7.2. (The use of alum as a coagulant has a side effect of lowering the pH of the water. ) Lowering the pH often increases the corrosiveness of the water to piping systems and household plumbing. Because the lowering of the pH in this case is small, it may not be necessary to add lime to raise the pH after coagulation to reduce corrosion. Lime systems are typically a nuisance both to operate and main- tain. Further investigation is needed during pilot plant testing. TREATMENT REQUIREMENTS AND DESIGN CONSIDERATIONS Treatment Goals Treatment goals should achieve or exceed EPA standards as set forth in the National Interim Primary and Secondary Drinking Water Regulations and State of Alaska drinking water regulations. Table 5-4 lists many of the more common water quality parameters and shows both EPA Maximum Contaminant Level (MCL) standards and natural levels in Eklutna Lake water taken from the power plant. More complete analyses including heavy metals, organic chemicals, and biological quality should be conducted before the design of treatment facilities begins, if Eklutna Lake is selected as a principal water supply source. Raw Water Treatability Based on the USGS water quality data and the water sampled from the power plant, Eklutna Lake displays relatively constant water 5-9 30- LEGEND Raw Water Alum Slow Mix Rate Rapid Mix Rate Turbidity Dosage rpm/duration rpm/duration (NTU) (mg/1) (minutes) (minutes) 28 12 70/6 10/15 28 12 70/6 40/15 X 26 12 90/6 20/15 W 26 12 70/6 20/15 + 11 80/4 35/15 n 20- 30 13 80/4 25/15 z l'- C, LU 40, 4-# LU LU 10-- *4 ANN 4% am ft I ssss m 8- am aft aaa on. as, 6- Imams= =+ 4- 2- OL 1b 115 2b A io i51 4ii SETTLING TIME (min) Figure 5-4 Settled Water Turbidity vs Settling Time for Various Mixed Speeds Table 5-4 WATER QUALITY STANDARDS AND EKLUTNA LAKE QUALITY Eklutna Lake EPA (MCL)' (Power Plant) Phxsical Factors Color (platinum cobalt units) 15 25-55C Odor (threshold odor No.) 3 -- c Turbidity (NTU) 1 26-30 Suspended Solids (mg/0 -- 4.3-5.6 Conductivity (umhos) 103-110 Coliform (No./100 ml) 1 0 pH 6.5-8.5 7.5-7.7 Chemical Factors (mg/1) Iron 0.3 .41-.9c Manganese 0.05 0.1-0.5 Chloride 250 1-1.0 Sulfate 250 10 Copper 1 -- Nitrate-N 10b .2-.37 Fluoride 2.4 .1 Alkalinity (mgll) 43-46 Hardness -- 56-61 Dissolved Solids 500 104-105 THM 0.10 Arsenic 0.05 .01 Barium 1.0 .5 Cadmium 0.010 .01 Chromium 0.05 .01- .05 Lead 0.05 .01 Mercur@ 0.002 .001 Selenium 0.01 .01 Silver 0.05 .01- .05 Sodium 20 2.-2.1 Zinc 5 -- Calcium -- 18-19 Si02 -- 3.01-3.1 Organics Endrin .0002 .0002 Lindane .004 .004 Methoxychlor .1 .1 Toxaphene .005 .005 2,4-D .1 .1 2,4,5-TP Silvex .01 .01 Radionuclides Gross Alpha Particle (pCi/1) 15 0.6�0.7 Gross Beta Particle (pCi/1) 50 4.5�5.6 amaximum Contaminant Level. bMaximum for annual average maximum daily air temperature 50 degrees F. CThese parameters exceed EPA MCL's. 5-11 quality characteristics. During the 8 coldest months when glacial melt ceases, the lake water is colder (approximately 4 degrees centigrade) with low turbidity (approximately 4 to 25 NTU). Dur- ing the summer, warmer weather and glacial melting increase water temperatures to 8 or 10 degrees centigrade, and turbidities range from 25 to 40 NTU. The higher turbidity caused by glacial flour is not likely to present a greater treatment problem. It is cold, low-turbidity water that generally presents the greatest treatment problems. In general, Eklutna Lake raw water will provide an excellent source of potable water. Only turbidity, color, and iron exceed the MCL established by the EPA regu 'lations. The proposed treatment processes should reduce all of these parameters to ac- ceptable limits. This will be verified during pilot plant testing, which is recommended as a part of subsequent predesign activities. Treatment Process On the basis of the limited year-round water quality data pres- ently available, it appears that different water treatment opera- tional modes will be required to accommodate summer and winter variations most efficiently. Figure 5-5 illustrates each of three possible operational modes. The first, conventional treatment, includes flash-mixing of coagulants, flocculation, sedimentation, and filtration. This mode would be applicable during the summer months when the lake water turbidity and color are each over approximately 20 units. Direct filtration involves most of the above facilities but would bypass the sedimentation basins. In-line filtration would bypass the flocculation and sedimentation basins and would move the co- agulant application point closer to the filters. Both direct and in-line filtration should be applicable for Eklutna Lake water treatment during the late fall, winter, and spring months when glacial melt is at a minimum and, therefore, raw water turbidity and color are each less than approximately 20 units and iron con- tent is low. Because of the cold water temperature and the small coagulant dosages required, it is not likely that direct or in-line filtration alone will be sufficient to remove the required amounts of color and iron in the summer months; therefore conventional treatment capability should be provided. Because the available data indicate a hardness of less than 100 mg/l, there is no appar- ent need for a lime softening process as suggested in the MAUS report. Conventional treatment is compatible with either the direct or in- line filtration process. The seasonal transition from one process to the other would be simple; bypass channels or piping achieve operational flexibility. As might be expected, operational cost of 5-12 FLASHMIX FLOCCULATION SEDIMENTATION FILTRATION RAW FINISHED WATER 000 WATER L SLUDGE SLUDGEI CONVENTIONAL TREATMENT DIRECT FILTRATION 000 IN-LINE FILTRATION Figure 5-5 5-13 Treatment Process Options either direct or in-line filtration will be substantially lower than that of conventional treatment. This results from lower chemical dosages, reduced sludge production, and less equipment maintenance. Experience With Ship Creek water at the Municipal Water Treat- ment Plant indicates that removal of color -and turbidity during periods of - low raw water turbidity requires special treatment beyond the addition of 10 to 15 mg/I of alum. The same may be true of Eklutna Lake water. Raw water quality data for samples taken during the test period of October 1981 as well as USGS data indicate an excess of color. To enhance the coagulation, sedimentation, and filtration processes for effective color and low turbidity removal, lime addition at the headworks or other treat- ment methods might be required. It is strongly recommended that, prior to final design, a pilot plant testing program be carried out over a full 1-year period with a minimum 1-mgd plant to establish process design criteria. This testing program should address iron, color, and turbidity removal; chemical dosages required over the full range of raw water parameters; filtration rates and media selection; and the effectiveness of the recommended treatment processes. Treatment Plant Figure 5-6 shows a typical filtration plant flow schematic, and Figure 5-7 shows a preliminary layout for a 70-mgd plant. The layout is amenable to phased construction. The plant could be constructed in increments, with basins and filters added as nec- essary with little disruption to continuing operation of existing facilities. A 7-acre site would be required. Desirable plant sites would be those that provide easy access dur- ing all weather conditions, minimize pumping requirements through careful site selection at the proper elevation, and eliminate the need for either raw or finished water pumping. Elimination of raw water pumping is more desirable because it provides con- struction cost savings and reduced equipment wear, while finished water pumping facilitates customer service along the transmission pipeline. Headworks The headworks contains facilities for applying and mixing chemi- cals plus a metering device to measure raw water flow into the plant. Chemicals can be mixed using either an "in-channel rapid mixer" or a metering device such as a Parshall flume. 5-14 HEADWORKS FLOCCULATION SEDIMENTATION FILTER CLEARWELL BASIN BYPASS PUMP STATION ............. ... ....... TO SLUDGE U DISPOSAL FINISHED ALUM WATER POLYMER POLYMER TRANSMISSION RAW DISINFECTANT bISINFECTAN WATER FLUORIDE T@ TOSLUDGE DISPOSAL DISINFECTAN FLUORIDE pH CONTROL T@ Figure 5-6 Typical Plant Flow Schematic 650' FINISHED FLOCCULATION /SEDIMENTATION BASINS PUMP i WATER STATION FILTER COMPLEX LO CLEARWELL BENEATH CHEMICAL FEED & STORAGE BU ILDING t Yf HEADWORKS RAW WATER AREA 6.7 ACRES Scale 1"=100' Figure 5-7 5-16 Preliminary Plant Layout Flocculation Flocculation is a building or bridging process wherein floc nuclei (aluminum hydroxide) resulting from coagulation (particles combin- ing chemically into larger aggregates) join together through nu- merous contacts and envelop suspended particles. After sufficient mixing, the floc grows to a size and density that settles readily. It is important in both the flash-mixing and flocculation zones that equipment be furnished with variable-speed drives to allow variation in energy inputs. Since optimum 'mixing requirements, vary from season to season, substantial waste of chemicals can occur if proper adjustments cannot be made. Sedimentation Dense floc particles, including suspended solids, settle out in the sedimentation area leaving comparatively clear water containing a minimum of floc. Because of the heavy rock flour load, the sed- imentation basins should be equipped with mechanical sludge re- moval equipment. It is anticipated that between 3 and 7 tons of equivalent dry solids sludge will be produced daily when the plant is operated at 70 mgd. Filtration System The settled water, containing a small amount of unsettled floc, proceeds from the sedimentation area to the filters. The filters remove the remaining floc. Granular media filters consist of either two or three layers, each exhibiting a different size and specific gravity. The largest grain media, having the lowest specific gravity, is located at the top of the filter with progres- sively smaller and heavier sizes toward the bottom. This ar- rangement permits floc and sediment particles to be removed throughout the entire filter rather than mostly at the surface, as typically occurs in sing le-grain-med ia filters. The addition of polymer as a filter aid immediately ahead of filtration improves floc removal within a filter, even at higher filtration rates. A nominal filtration rate of 6 gallons per minute per square foot is suggested for an Eklutna Lake filtration plant. Pilot filter testing is needed to (1) verify the design filter rates, both summer and winter; (2) select filtering media specifically for local conditions; and (3) identify which filter aid chemicals are needed and in what quantity. Wastewater Disposal Sludge containing rock flour and sediment from the lake water would be produced in two locations in the plant. The first is the sedimentation basin underflow and the second is the filter back- wash water. At a plant flow rate of 70 mgd and a raw water tur- bidity of 30 NTU, the quantity of sludge produced would equal 5-17 7 tons per day of dry solids, which would equal approximately 100 cubic feet per day of solids. Removal of solids from sludge for ultimate disposal is often the most complex problem to be solved in the design of a water treatment plant. Generally, there are two methods of dewatering sludge solids. The first includes drying by natural means such as evaporation, percolation, and freezing. The second is by such mechanical means as vacuum filters, filter presses, and centrifuges. The cost for mechanical dewatering is usually three to ten times the cost for natural drying. For Eklutna, however, the most practical choice of sludge (and backwash water) disposal is to pipe it directly to Knik Arm, with- out clewatering. At 3 percent of plant production (70 mgd), the volume of wastewater in the summer would be approximately 2 mgd. This wastewater could be piped to Knik Arm without. pumping provided the treatment plant is located at an elevation above sea level such that sufficient head is available for gravity f low. Disinfection With the addition of disinfection agents, the water leaving the filters is potable and ready for transmission and distribution to the public. Although chlorine has been the universal disinfectant in public water works, further consideration should be given to the use of other disinfectants for preliminary disinfecting, while continued use of chlorine or hypochlorite will likely remain the choice for postdisinfection as the water enters the transmission and distribution systems. Further investigation is required prior to selecting disinfectants and their application points within the plant. Trihalomethane* formation potential needs to be determined. Alternative Treatment Methods Other treatment methods were also considered, some reported by others in previous studies. These include hydroclone separators, screening with microstrainers, and precoat filters. Only precoat filtration is applicable to the Eklutna Lake conditions and could be considered an alternative to granular media filtration. Histori- cally, granular media filtration is the choice for public water sup- plies, especially installations over 5 mgd. The disadvantage of precoat filtration is the hazard of loss of the precoat from the fil- tering septum, which permits raw water to short circuit through the filter. Loss of precoat can be caused by hydraulic surges, changing flow rate, power failure, and operator error. Granular media filters do not present these handicaps except, possibly and to a lesser degree, the potential for operator error. *An organic compound formed when certain natural organic com- pounds (particularly humic acids) come in contact with chlorine. Thought to cause cancer in animals. 5-18 COST ESTIMATE Table 5-5 shows the total estimated project costs for a 70-mgd plant as well as a 23.33-mgd plant, which provides for ultimate plant development in three equal increments. Table 5-5 ESTIMATED PROJECT COSTS a Plant Capacity 23-1/3 m9d 70 mgd Capital Construction $10,900,000 $26,000,000 (Anchorage) Contingency, Bonds & In- surance, and Technical, Adm. & Legal Services (Anchorage) 6,459,000 15,400,000 TOTAL CAPITAL COSTS b $17,359,000 $41,400,000 Annual O&M Labor $ 443,000 $ 895,000 Chemicals 335,000 1,006,000 Power 193,000 580,000 Maintenance Materials 98,000 212,000 Miscellaneous 6,000 17,000 TOTAL ANNUAL O&M COSTS $1,075,000 $2,710,000 aIn January 1981 dollars. bLand costs are not included. The estimated construction costs and operation and maintenance costs are based on actual experience with plants constructed and operated in the Pacific Northwest, and have been adjusted to re- flect costs for Alaska. They are also based on EPA Estimating Water Treatment Costs, Volumes 1 and 2, and on t_Fe___MAU5, Vol- ume 2. Thes@-e@@T`Imates are considered as "order-of-magnitudell estimates with a -30 to +50 percent reliability range. Construction costs assume the use of reinforced concrete con- struction with all basins and filters enclosed. The estimates in- clude sludge piping to Knik Arm but do not include raw water and finished water pumping, standby power, or water transmission piping. 5-19 Construction costs are for January 1981, using an Engineering News Record Construction Cost Index of 347. Land costs are not included in the estimates; the site requirements are 7 acres for the plant and an additional 10 acres for sludge-drying ponds if sludge is not piped to Knik Arm. SUMMARY AND CONCLUSIONS USGS water quality data and field and laboratory testing indicate that Eklutna Lake water is treatable. Treatment facilities will require two different seasonal treatment processes that can be provided in a single water treatment plant. Transition between processes will occur in June and October, correlating with glacial melting at the lake's headwaters. The recommended treatment processes are (1) flocculation, sedi- mentation, high-rate filtration, and disinfection for the higher turbidity, glacial melt period and (2) coagulation, high-rate filtra- tion, and disinfection for the lower turbidity period during the colder months. The estimated capital cost for a 70-mgd plant facility is $41.4 mil- lion (1981 construction dollars). Operation and maintenance costs are estimated at $2.7 million per year. If Eklutna Lake is selected as the source for additional water supply, we recommend the following prior to starting final design: 0 Pilot plant tests for a full year to determine applicable process design criteria and the effects of lime softening (if needed) 0 An investigation of disinfection alternatives to identify trihalomethane formation potential (formation of poten- tially carcinogenic substances during the disinfection process) 0 Sludge disposal alternatives and cost research 0 Use of polymers as a substitute coagulant or as a coag- ulant aid If other sources of water are used to supplement Eklutna Lake water, those sources should also be investigated. 5-20 Chapter 6 NO ENERGY IMPACT AND COST ANALYSES This chapter contains discussions of the present use of Eklutna Lake as a hydroelectric reservoir, the impact of the three Eklutna water diversion alternatives on the south-central Alaska power supply, and the total capital and operation and maintenance costs associated with each of the three alternatives. The power re- quirements and costs of these alternatives are then compared with those for the Eagle River diversion. BACKGROUND The normal peaking capability of the Eklutna Hydroelectric power plant is 35 MW, and it has operated at 36 MW on occasion. The output of the plant is sold to the Anchorage Municipal Light and Power Utility and the several electric associations operating in south-central Alaska. The contracts for the sale of power pro- vide for delivery of a firm supply of energy at an annual load factor of 58.22 percent. Energy generated in excess of this firm supply is sold at a reduced rate as nonfirm, interruptible energy. The entire project was constructed on federally owned land which had been reserved for a power site. At present, the operation of the plant is by the APA. RESERVOIR OPERATIONS Since the Eklutna hydroelectric project uses essentially all of the inflow to Eklutna Lake, any diversion of water from Eklutna Lake, upstream of the turbines, for a municipal water supply project will reduce the total annual energy production of the hydroelec- tric project. In order to evaluate Eklutna Lake as an alternative water source for Anchorage, an estimate of the impact on power generation at the power plant was made. Historical records from the hydroelectric project were used. Historical Lake Level and Hydroelectric Water Use The annual cycle of the level of Eklutna Lake is a rough indicator of the amount of power that can be generated at Eklutna Lake. The lake level usually varies between elevation 825 and elevation 870 throughout the year, with the lowest levels occurring in March through May and the highest normally occurring in Septem- ber and October. An analysis has been made by the U.S. Bureau of Reclamation to determine the target daily lake levels to provide the optimum hydroelectric generation. These lake levels, when plotted, form a rule curve for hydroelectric generation (Figure 6-1). Near the top of Figure 6-1, at elevation 871.0, a line indi- cates the spillway crest elevation. The spillway was constructed 6-1 IEST 871 ft 180 170 160 150 860 40006@ - 140 'p -130 -120 z 0 79 -110 850- 461 > -100 LU -i LU Uj -90 a LU .:t 0 -80 cc < 940 0 LL -70 fA LU U) -60 @e cc < LU -50 F- 830- -40 -30 820- -20 -10 8101 OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP WATER YEAR Figure 6-1 Eklutna Lake Levels Since 1965 in 1965 after the 1964 earthquake. Prior to that time, the crest was slightly lower on a different dam. The figure indicates that the monthly changes in lake levels have been similar each year, but are either above or below the rule cu rve. A statistical analysis of the total annual inflow to Eklutna Lake (total annual inflow is shown on Table 2-1, Chapter 2) was made to determine the predictable inflow range. It showed that the average low flow with a 50-year return period is approximately 160,000 ac-ft (143 mgd), and the 50-year high flow is approxi- mately 324,000 ac-ft (289 mgd). The historical record of 1947 through 1981 shows that the range of inflows is from 164,700 to 328,800 ac-ft (147 to 294 mgd). The water usage of the Eklutna hydroelectric project was also analyzed. Monthly and annual water usages were statistically analyzed to determine whether any of the historical data were from unusually heavy or low water usage periods. (See Table 2-2 of Chapter 2 for actual water usage.) On an annual basis, water usage was not unusually high or low; however, during several months, abnormal water usage did occur. Water usage was never higher than expected, but it was lower than expected during 4 months of the historical record. (April 1971, April 1972, July 1973, and August 1973.) Inflow to Eklutna Lake was below aver- age during these months. Lake levels were also below normal. ,This indicates that power generation was cut back during these months because of adverse hydrologic conditions. It is probable that, in the future, low lake levels and low inflow could again cause curtailment of the power plant's water usage. Predicted Reductions in Hydroelectric Water Supply The percent reduction in energy production that could occur at the Eklutna hydroelectric project because of diversion for a muni- cipal water supply was estimated. First, a relationship among Eklutna Lake level, water usage of the project, and the amount of energy generated was determined. This relationship made it pos- sible to predict potential hydroelectric generation based on the lake level and the amount of water used. From the MAUS (Vol- ume 2), it has been estimated that 25 mgd diversion will be re- quired in the 1990's, 50 mgd diversion by 2005, and 70 mgd by 2012. Planned water supply developments in the Anchorage Bowl will delay the need for intermediate and peak diversions. These diversion amounts were considered in the estimates for energy reduction. As with the Eagle River dam analysis (Appendix 11), the demands are assumed to be constant year-round. In a future detailed analysis, demand variation considerations will be appro- priate. Table 1-10, "Water Demand Increase" on page 1-15 of MAUS, lists in 5-year increments the population and water demand projections, including the increased demand over 1977. These 6-3 projections are sub ect to revision, possibly downward, and new demand projections should be made prior to final design of any major water supply project. For water year 1977, the high lake level year, monthly estimates of energy reduction due to diversions of 25 mgd, 50 mgd, and 70 mgd were made. The water used by the hydroelectric project was reduced by the amount diverted, which assumes all of the di- verted water comes from Eklutna Lake somewhere upstream of the turbines. This corresponds to Alternative 2. During periods of spill at Eklutna Lake, smaller water reductions were used since excess water was available. The reduced monthly volume of water available for use by the hydroelectric project was converted to potential energy output. These hypothetical energy outputs were then compared to the actual generation to determine the percen- tage of energy reduction. Calculations of monthly energy reduction also were made for water year 1973, the low lake level year, the monthly averages of water years 1966 through 1980, and the monthly averages of 1971 through 1980. Average annual energy reductions for these com- putations ranged from 10 to 16 percent for 25 mgd diversion, 19 to 32 percent for 50 mgd diversion, and 27 to 44 percent for 70 mgd diversion. The percent of energy reduction based on average annual values only, as compared to monthly values, was computed for water years 1966 to 1981. Reduction values ranged from 8 percent to 20 percent for 25 mgd diversion, 19 to 37 percent for 50 mgd diversion, and 28 to 49 percent for 70 mgd diversion. It estimated that the average annual hydroelectric energy reduc- tion for a 25-mgd diversion from Eklutna Lake would be 14 per- cent (22 million kWh). For a diversion of 50 mgd, the reduction would be 28 percent (44 million kWh), while for a 70-mgd diver- sion, the energy reduction would be about 39 percent (61 million kWh). Table 6-1 lists the average and extreme monthly variations calcu- lated for the period after the 1964 earthquake. ENERGY LOST BY DIVERSION OF WATER UPSTREAM OF TURBINES Alternative 1 uses lake water after it passes through the turbines. Both Alternative 2 and Alternative 3 would divert water above the turbines and would reduce the energy produced. Alternative 2, the tunnel diversion, would divert all of the water supply flow away from the power project. The energy lost would average from 11 million kWh in 1985 to 40 million kWh in the year 2000, and up to 61 million kWh in the year 2012 when it is expected that the full 70 mgd will be required. These power supply im- pacts are summarized in Table 6-2 and Figure 6-2. 6-4 Table 6-1 a EKLUTNA HYDROELECTRIC ENERGY REDUCTION SUMMARY Energy Reduction (% Energy Reduction (%lb Energy Reduction (% (25-mgd Diversion) (50-mgd Diversion) (70-mgd Diversion) Month Avg Max Min Avg Max Min Avg Max Min January 14 14 11 27 27 24 38 38 33 February 18 19 12 32 33 27 41 46 37 March 17 19 10 32 35 23 43 50 33 April 21 22 15 37 39 30 49 53 41 May 14 21 8 30 42 16 42 55 23 June 13 21 10 30 42 20 39 58 28 July 13 36 9 27 75 19 38 100 26 August 13 17 0 26 70 0 36 85 0 September 16 19 0 30 45 0 41 79 0 October 12 17 6 25 35 17 36 49 25 Novembee 13 20 11 25 41 21 36 57 29 December 10 15 10 23 29 21 33 41 30 Year 14 20 8 28 43 18 39 59 25 aBased on Eklutna hydroelectric project records for water years 1966-1980 for average and water years 1973, 1977, and 1980 for maximum,and minimum analysis. bAll water diverted upstream of turbines. Alternative 3 would obtain some water from sources below the lake, so it would divert less water from the hydroelectric project. In 2012, 38 percent would come from below the lake and only 62 percent would be diverted from the hydroelectric project. The average annual loss of energy would be 3.6 million kWh in 1985, 23 million kWh in 2000, and 40 million kWh in 2012. This is a smaller impact on hydroelectric generation than that which would be produced by Alternative 2. ENERGY REQUIRED FOR PUMPING Both Eklutna Alternatives 1 and 3 would require energy for pumping water to the treatment plant and to Anchorage. All of 6-5 Table 6-2 POWER SUPPLY IMPACT OF ALTERNATIVE a DIVERSIONS OF EKLUTNA WATER AND EAGLE RIVER Eagle Eklutna Alternative River 1 2 3 Energy Impact (MWh) Reduction in Generation 14 mgd 11,000 3,562 45 mgd 40,000 22,759 70 m9d 61,629 40,307 Pumping Energy 14 mgd 10,719 -- 10,959 5,700 45 mgd 45,596 42,286 19,500 70 mgd 81,895 75,265 32,700 Treatment Plant 14 mgd 1,150 1,150 1,150 1,150 45 m9d 3,900 3,900 3,900 3,900 70 mgd 6,108 6,108 6,108 6,108 Total Energy Impact 14 mgd 11,869 12,150 15,671 6,850 45 mgd 49,496 43,900 68,945 23,400 70 mgd 88,003 67,737 121,680 38,808 Capacity Impact (kW) Pumping Capacity 14 mgd 1 350 -- 1,340 1,000 45 mgd 6,000 5,220 3,000 70 mgd 11,250 9,230 5,400 Treatment Plantb 14 mgd 150 150 150 150 45 mgd 500 500 500 Soo 70 mgd 775 775 775 775 Total Capacity Impact 14 mgd 1,500 150 1,490 1,150 45 mgd 6,500 500 5,720 3,500 70 mgd 12,025 775 10,005 6,175 aWithout additional sources developed in the Anchorage Bowl, 14 mgd is needed by 1985, 45 mgd by 2000, and 70 mgd by 2012 (MAUS, 1979). Development of Anchorage Bowl water sources will postpone the need for these average volumes of water from a source outside bof the Bowl. Assumes operation at 90-percent plant factor. 6-6 150 100 X e\ 50 P, ta P, PX .00000.0 a @.erv oil) %_ C)am Vd Ftes ezi-1010to E GLE 0 1 10 20 30 40 50 60 70 WATER SUPPLY (mgd) *REPRESENTS THE REDUCTION IN THE EKLUTNA HYDROELECTRIC FACILITY ENERGY GENERATION AND THE ENERGY REQUIRED FOR PUMPING AND WATER TREATMENT. Figure 6-2 Eklutna Alternatives and Eagle River Dam and Reservoir Estimated Annual Impacts on Energy Production Alternative 2 flow is by gravity; therefore pumping energy would not be required. Except for the first iew years of operation, Alternative 1 would require more pumping energy than would Al- ternative 3 because much of the Alternative 1 water would be diverted from near sea level at the tailrace of the power project. The pumping energy requirements of Alternative 1 would increase from 10.7 million kWh in 1985 to 81.9 million kWh in 2012 when the full 70-mgd of water are estimated to be needed. The pumping 6-7 would also require 1,350 kW of capacity in 1985, increasing to 11,250 in 2012. Energy requirements for Alternative 3 would in- crease from 10.9 million kWh in 1985 to 75.3 million kWh in 2012. Capacity requirements would increase from 1,340 kW in 1985 to 9,230 kW in 2012. The Eagle River project would also require energy and capacity for pumping. The energy requirements would increase from 5.7 million kWh in 1985 to 19.5 million kWh in 2000 and to 32.7 million kWh in 2012. Capacity requirements would increase from 1,000 kW in 1985 to 3,000 kW and 5,400 kW in 2000 and 2012, respectively. ENERGY REQUIRED FOR THE TREATMENT PLANT Electrical energy would be required for the operation of a water treatment plant for each Eklutna alternative and for the Eagle River dam and reservoir project. Energy requirements, which would be the same in each case, would increase from 1.2 million kWh in 1985 to 3.9 million kWh in the year 2000 and to 6.1 million kWh in 2012. EFFECT ON SOUTH-CENTRAL ALASKA POWER AND ENERGY SUPT17- Each alternative will reduce the amount of electric energy avail- able for other uses on the electric systems serving south-central Alaska. These are the electric associations and the electric sys- tems with contracts for Eklutna energy. Alternatives 1 and 3 would also impact the capacity available to serve other customers. Alternative 3 would have the greatest impact on the electrical sup- ply because it would both reduce generation at Eklutna and re- quire pumping energy and capacity. Altogether, under average water conditions Alternative 3 would reduce the supply of elec- tricity for other uses by 15.7 million kWh in 1985, 68.9 million kWh in 2000, and 121.7 million kWh in 2012. Alternative 3 also would reduce the capacity of the systems to carry their other peak loads by 1,490 kW in 1985, 5,720 kW in year 2000, and 10,005 kW in 2012. Alternative 1 would have the second greatest impact on the elec- tric supply. Although it would not reduce generation at Eklutna, it would require large amounts of energy and capacity for pump- ing. Energy requirements would increase from 11.9 million kWh in 1985 to 49.5 million kWh in 2000 and to 88 million kWh in 2012. Alternative 2 would have the least impact on the electric supply. Although it would reduce the energy generated at the Eklutna project, it would require no pumping capacity or energy. 6-8 COST OF REPLACING ENERGY LOST TO THE ELECTRIC SYSTEMS The estimated electric energy impact of each Eklutna water supply alternative is either the result of a reduction of the water supply to the Eklutna hydroelectric generating plant or is due to the pumping energy needs of the water supply project. Alternative 3 reduces the water supply to the Eklutna plant and requires pump- ing energy. The lost energy will have to be replaced and new pumping energy demands generated if the growing electrical loads of the region are to be met. Though the region's electric energy prices are now relatively low, the future cost of electric power is expected to be much greater. At present, most of the region's electric power is generated in thermal plants using relatively in- expensive natural gas. In the future, when natural gas prices are decontrolled at the well head, gas prices (on a Btu basis) are expected to rise to a level close to or equal to the cost of No. 2 heating oil. At that time it is believed that increases in power supply will be supplied from coal-fired thermal plants with generation cost of about 8.66 cents per kWh (1981 prices) compared with the current cost of less than 2 cents per kWh.. The energy lost at the Eklutna power plant and the energy re- quired for pumping diverted Eklutna Lake water supply to Anchorage is assumed to cost 8.66 cents per kWh. The annual energy impacts of the three Eklutna alternatives and the Eagle River project are shown in Table 6-3 and Figure 6-3. The total cost of energy for Alternative 2, the tunnel tap, is 84 percent greater than for the Eagle River dam and reservoir project. En- ergy costs for the other alternatives are substantially higher. CAPITAL COSTS Order-of-magnitude capital cost estimates (reflecting November 1981 construction costs) were made for the three alternative meth- ods of diverting Eklutna water to Anchorage. Order-of-magnitude estimates have a reliability range of -30 to +50 percent. Tables 6-4 through 6-6 show itemized costs for the Eklutna water supply Alternatives 1, 2, and 3. Alternative 2, the most expen- sive, at $151 million, is 16 percent higher than Alternative 3, the least expensive, which costs $131 million. Table 6-7 summar- izes the identifiable costs ($122 million) for the Eagle River dam and reservoir project. This does not include certain substantial cost items, such as: 0 Acquisition of approximately 2,500 acres of reservoir land owned by Eklutna, Inc. 0 Old Eagle R.iver Dump water quality impacts mitigation 6-9 Table 6-3 COST OF FUTURE ENERGY AND CAPACITY INCURRED BY DIVERSION OF EKLUTNA AND EAGLE RIVER WATER TO ANCHORAGE Cost in $1,000 E a g Fe Eklutna Alternative River 2 3 Annual Cost of Energya 14 mgd 1,028 1,052 1,357 593 45 mgd 4,286 3,802 5,971 2,026 70 mgd 7,621 5,866 10,537 2,832 Annual Cost of Capacityb 14 mgd 108 4 107 83 45 mgd 468 36 412 252 70 mgd 865 56 720 389 Annual Cost of Impact 14 mgd 1,136 1,056 1,464 676 45 mgd 4,754 3,838 6,383 2,278 70 mgd 8,486 5,922 11,257 3,221 aBased on October 1981 analysis of a 200-MW mine-mouth coal- fired steam electric station operating at 50 percent plant factor: 8.66@IkWh. bBased on 1.8 x annual capacity cost of most recently com- pleted pump station built on the West Coast: $72/kW/yr. 0 Facilities and mitigation measures for fish passage 0 Special requirements determined during environmental analysis Work has not been done to determine the cost impact of these items on the feasibility of the Eagle River dam and reservoir pro- ject. It is anticipated that these costs will be many millions of dollars. The capital and operation and maintenance costs for all four proj- ects are shown on a 1981 annual basis in Table 6-8. Fifty-year, 8-percent annualizing is assumed for the capital costs. Total an- nual costs for the Eklutna alternatives are also shown in Fig- ure 6-4. Alternative 3 is the least expensive project until flows are 35 mgd, and most expensive at 70 mgd. Up to 30 mgd, Al- ternatives 1 and 2 are essentially equal; Alternative 2 is less expensive than either Alternative 1 or 3 at 70 mgd. 6-10 Figure 6-3 Eklutna Alternatives and Eagle River Dam and Reservoir Annual Cost of Energy and Capacity Requirements Although the cost estimate for the Eagle River dam does not in- clude all items (such as reservoir land, old dump mitigation, and fish facilities, for example), those that are included were treated in greater detail than were the estimates for the Eklutna project. Extensive field data and detailed mapping were used for the Eagle River tasks (Appendixes II and IV), for example. Almost no new field data were collected and USGS scale maps were used to de- velop the three Eklutna alternatives. Therefore, the reliability of the Eklutna cost estimate must be less than for the Eagle River Dam project. The Eklutna design can be improved and made less conservative if more detailed studies are conducted. Figure 6-5 illustrates that Alternative 2, for example, may be quite compar- able in total annual cost to the Eagle River project. 6-11 Table 6-4 ORDER-OF-MAGNITUDE COST ESTIMATE FOR ALTERNATIVE 1 1 tem Quantity Unit Price- Total Cost General Requirements lump sum lump sum 5,000,000 Transmission Piping Clearing and Grubbing lump sum lump sum 330,000 Pipe: 54-inch, Class 100-250 117,000 If $290 33,930,000 48-inch, Class 150 41,000 If $260 10,660,000 30-inch, Class 150 1,200 If $175 210,000 Valves and Appurtenances lump sum lump sum 940,000 Stream Crossings lump sum lump sum 180,000 Railroad Crossings 2 each $145,000 290,000 Eagle River Crossing lump sum lump sum 120,000 Pavement Replacement lump sum lump sum 1,950,000 Telemetry and Controls lump sum lump sum 440,000 Tailrace Pump Station and Intake Structure lump sum lump sum 4,600,000 Mirror Lake Booster Pump Station lump sum lump sum 3,100,000 Water Treatment Plant lump sum lump sum 26,000,000 Water Treatment Plant Pump Station lump sum lump sum 4,800,000 Eklutna River Diversion Structure and Piping lump sum lump sum 750,000 Subtotal 93,300,000 Bonds and Insurance (2.5%) 2,330,000 Legal, Administrative, and Engineering (20%) 18,660,000 Subtotal 114,290,000 Contingency (30%) 34,290,000 Total 148,580,000 6-12 Table 6-5 ORDER-OF-MAGNITUDE COST ESTIMATE FOR ALTERNATIVE 2 I tem Quantity Unit Price Total Cost General Requirements 4,500,000 Transmission Piping Clearing and Grubbing lump sum lump sum 330,000 Pipe: 60-inch, Class 150 7,400 If $300 2,220,000 Class 200 29,600 If $320 9,470,000 Class 250 37,600 If $355 13,350,000 Class 300 17,000 If $375 6,380,000 Class 350 4,100 ff $415 1,700,000 Class 400 33,200 If $435 14,440,000 48-inch, Class 150 41,000 If $260 10,660,000 ' Class 400 1,400 If $450 630,000 30-inch' Class 150 1,200 If $175 210,000 Valves and Appurtenances lump sum lump sum 1,040,000 Stream Crossings lump sum lump sum 180,000 Railroad Crossings 2 each 145,000 290,000 Eagle River Crossing lump sum lump sum 120,000 Pavement Replacement lump sum lump sum 1,950,000 Telemetry and Controls lump sum lump sum 440,000 Penstock/Tunnel Connection lump sum lump sum 1,000,000 Water Treatment Plant lump sum lump sum 26,000,000 Subtotal 94,910,000 Bonds and Insurance (2.5%) 2,370,000 Legal, Administrative, and Engineering (20%) -18,980,000 Subtotal 116,260,000 Contingency (30%) 34,880,000 Total 151,140,000 6-13 Table 6-6 ORDER-OF-MAGNITUDE COST ESTIMATE FOR ALTERNATIVE 3 1 tem Quantity Unit Price Total Cost General Requirements 4,000,000 Transmission Piping Clearing and Grubbing lump sum lump sum 330,000 Pipe: 54-inch, Class 100-250 84,800 If $290 24,590,000 48-inch, Class 150 41,000 If $260 10,660,000 30-inch, Class 150 1,200 If $175 210,000 Valves and Appurtenances lump sum lump sum 660,000 Stream Crossings lump sum lump sum 180,000 Eagle River Crossing lump sum lump sum 120,000 Pavement Replacement lump sum lump sum 1,400,000 Telemetry and Controls lump sum lump sum 440,000 Eklutna Lake Pump Station, Intake Structure, and Power Transmission Line lump sum lump sum 5,250,000 Mirror Lake Booster Pump Station lump sum lump sum 3,100,000 Water Treatment Plant lump sum lump sum 26,000,000 Water Treatment Plant Pump Station lump sum lump sum 4,800,000 Eklutna River Diversion Structure and Piping lump sum lump sum 750,000 Subtotal 82,490,000 Bonds and Insurance (2.5%) 2,060,000 Legal, Administrative, and Engineering (20%) 16,500,000 Subtotal 101,050,000 Contingency (30%) 30,310,000 Total 131,360,000 6-14 Table 6-7 ORDER-OF-MAGNITUDE COST ESTIMATE FOR EAGLE RIVER WATER SUPPLY DAM AND PIPELINE I tem Quantity Unit Price Total Cost General Requirements lump sum lump sum 3,650,000 Transmission Piping Clearing and Grubbing lump sum lump sum 330,000 Pipe: 48-inch, Class 150 41,000 If $260 10,660,000 30-inch, Class 150 1,200 If $175 210,000 27-inch, Class 150 5,200 If $160 830,000 24-inch, Class 150 20,000 if $140 2,800,000 20-inch, Class 150 23,500 If $120 2,820,000 18-inch, Class 150 12,600 If $110 1,390,000 10-inch, Class 150 14,200 If $ 60 850,000 Valves and Appurtenances lump sum lump sum 1,750,000 Ship Creek Crossing lump sum lump sum 60,000 Eagle River Crossing lump sum lump sum 120,000 Trench Stabilization and Compacted Embankment lump sum lump sum 40,000 Pavement Replacement lump sum lump sum 1,130,000 Telemetry and Controls lump sum lump sum 50,000 Eagle River Pump Station and Inlet Structure lump sum lump sum 6,750,000 Eagle River Booster Pump Station lump sum lump sum 1,000,000 Eagle River Dam (excl. land) lump sum lump sum 16,200,000 Water Treatment Plant lump sum lump sum 26,000,000 Subtotal 76,640,000 Bonds and Insurance (2.5%) 1,920,000 Legal, Administrative, and Engineering (20%) 15,330,000 Subtotal 93,890,000 Contingency (30%) 28,170,000 Total 122,060,000 6-15 25- z 20- CL LU 0 < @- r- 0 z x cc ;@ 0 OEM LL z _j 0 < 0 Z 0 0 ()0 z Z LU (L 15- 0 0 10 20 30 40 50 60 )0 WATER SUPPLY (mgd) NOTE: Assume 50 Year, 8% for Capital Annualization. Figure 6-4 Eklutna Alternatives Total Annual Cost 6-16 25 @XO -jx A P_ 20 'Ae j 0. 0 erll T -clot FSIX w [email protected]%%_Ocosl le .U 0-0 va t4cs _j Z << z .. ........ woo ................. . . . . . . ... ...... C.) Z x 15 to 0 2 cc LL Z _j cl) 0<0 L) -0 z _j 0 00 < p M D 10 Z<- < w EAGLE RIVER DAM AND RESERVOIR- 0. 0 CONTINGENCY OF UP TO $30 x106 FOR PURCHASE OF RESERVOIR LAND, MITIGATION OF OLD EAGLE RIVER DUMP, FISH FACILITIES AND/OR MITIGATION, ENVIRONMENTAL STUDY AND MITIGATION. 5 0 10 20 30 40 50 60 70 WATER SUPPLY (mgd) Figure 6-5 Eklutna Alternative 2 vs Eagle River Dam and Reservoir 6-17 Total Annual Cost Table 6-8 ANNUAL COST SUMMARY EKLUTNA ALTERNATIVES AND EAGLE RIVER PROJECT Alternative Annual Cost 14 mgd 45 mgd- 70 mgd ALTERNATIVE 1 (Capital Cost = $148,580,000) Annual Capital Cost 12,111,000 12,111,000 12,111,000 (50 years @ 8%) Power and Energy Costs 1,136,000 4,754,000 8,486,000 O&M (excluding power) 641,000 1,581,000 2,353,000 Total 13,888,000 18,446,000 22,950,000 $/ac-ft 857.28 365.99 292.73 $/1,000 gallons 2.63 1.12 0.90 ALTERNATIVE 2 (Capital Cost = $151,140,000) Annual Capital Cost 12,320,000 12,320,000 12,320,000 (50 years @ 8%) Power and Energy Costs 1,056,000 3,838,000 5,922,000 O&M (excluding power) 614,000 1,464,000 2,144,000 Total 13,990,000 17,622,000 20,386,000 $/ac-ft 863.58 349.64 260.03 $/1,000 gallons 2.65 ALTERNATIVE 3 (Capital Cost = $131,360,000) Annual Capital Cost 10,708,000 10,708,000 10,708,000 (50 years @ 8%) Power and Energy Costs 1,464,000 6,383,000 11,257,000 O&M (excluding power) 633,000 1,578,000 2,350,000 Total 12,805,000 18,669,000 24,315,000 $1ac-ft 785.68 368.79 309.09 $/1,000 gallons 2.43 1.14 0.95 EAGLE RIVER b (Capital Cost = $122,060,000) Annual Capital Cost 9,949,000 9,949,000 9,949,000 (50 years @ 8%) Power and Energy Costs 676,000 2,278,000 3.221,000 0 &IA (excluding power) 691,000 1,631,000 2,393,000 Total 11,316,000 13,858,000 15,563,000 $/ac-ft 698.52 275.96 198.51 $/1,000 gallons 2.14 0.85 0.61 Note: A-IT costs are in 1981 Dollars aWithout additional sources developed in the Anchorage Bowl, 14 mgd is needed by 1985, 45 mgd by 2000, and 70 mgd by 2012 (MAUS, 1979). Development of Anchorage Bowl water sources will postpone the need for these average volumes of water from a source outside the Bowl. bDoes not include major capital cost items identified in text such as reservoir land and fish facilities. 6-18 SUMMARY The energy impact of a new water source for Anchorage will be considerable. This is especially true for the Eklutna alterna- tives. Alternative 1 will not impact the energy production at the Eklutna hydroelectric facility, but pumping and treatment energy .requirements, at 70 mgd, will be 88 million kWh per year. Alter- native 2 will reduce the average energy output of the hydroelec- tric facility by 40 percent, (62 million kWh per year) and use 6 million kWh per year for treatment. Alternative 3 will reduce the average energy output of the hydroelectric facility by 26 per- cent (40 million kWh per year) and use 81 million kWh per year for pumping and treatment. The Eagle River water supply proj- ect will use 39 million kWh per year for pumping and treatment at 70 mgd. The capital costs of the alternatives range from $131 to $151 mil- lion. The capital cost for the Eagle River dam project is ex- pected to range from $122 to $160 million, depending on the cost for reservoir land, dump water quality impact mitigation, fish facilities and habitat impact mitigation, and other environmental concerns. The Eagle River dam would be a complex structure and proper operation of the reservoir is somewhat complex. Many uncertainties exist regarding the dam construction. The total annual cost of building and operating a new 70-mgd water supply facility at Eklutna ranges from $20 to $24 million. The partial cost estimate for the Eagle River dam project indicates a total annual -cost of $16 million. If additional capital costs should be $30 million, for example, the total annual cost for 70 mgd is over $18 million. As shown in Figure 6-5, refinement of costs for the Eklutna and Eagle River projects may prove that costs for Eagle River are similar to those of at least one of the Eklutna alternatives. 6-19 NN Chapter 7 ENVIRONMENTAL CONSIDERATIONS This chapter identifies the various environmental concerns of reg- ulatory agencies and interested groups regarding the diversion of water from the Eklutna Watershed. It then compares the three diversion alternatives with each other and the Eagle River Project. IDENTIFICATION OF ENVIRONMENTAL CONCERNS Preliminary studies of possible diversion of water from the Eklutna watershed indicated relatively less environmental impact than would be associated with diversion from the Eagle River (Tryck, Nyman, and Hayes, 1973; U.S. Army, Corps of Engineers, 1979). Having identified specific environmental concerns about a reser- voir and treatment plant at Eagle River (during Task 2 studies), we contacted the same regulatory agencies and interested parties regarding the three Eklutna diversion alternatives. From our contacts with these regulatory agencies, interested par- ties, and the Municipality of Anchorage we derived a list of en- vironmental concerns. Where possible, information from previous reports has been included. The identification process did not include public hearings or meetings, and thus is not fully repre- sentative of the sentiments of all people potentially affected by the various water-supply options. The following agencies and entities were contacted: Federal Agencies 0 Department of the Army Corps of Engineers Fort Richardson Command, Environmental Office and Utilities Division 0 Department of Commerce, National Marine Fisheries Service 0 Department of Energy, Alaska Power Administration 0 Department of Interior, U.S. Fish and Wildlife Service 0 Environmental Protection Agency 7-1 State of Alaska 0 Alaska Department of Environmental Conservation 0 Alaska Department of Fish and Game 0 Alaska Department of Naturai Resources 0 Division of Forest, Land and Water Management 0 Division of Geological and Geographic Surveys 0 Division of Parks 0 Eklutna, Inc. Municipality of Anchorage 0 Planning Department 0 Water and Sewer Utilities 0 Department of Law ENVIRONMENTAL CONCERNS The concerns expressed by the agencies and other groups con- tacted fell within the broad categories of potential impacts on fisheries, wildlife, land use, power production, water quality, and institutional arrangements (rights-of-way) within the project area. Fisheries Present fishery resources of the Eklutna watershed are not well known, but are not thought to be extensive. Studies to deter- mine the extent of the fishery resource would be necessary to establish whether instream flow studies would be required and to aid in establishing minimum flow requirements below the project for Alternatives 1 and 2. The proposed hatchery near the exist- ing Eklutna power plant (see Figure 4-5) should not be adversely affected by the water supply project; hatchery design effort should be coordinated with the Municipality of Anchorage to assure that room is provided for future facilities. Wildlife Wildlife resources will be impacted only during construction of the project, except possibly in the case of Alternative 3, which will require a powerline to the pump station at Eklutna Lake. The design and construction of the powerline should consider potential impacts on wildlife, particularly raptors. Land Use The availability of a reliable water supply is likely to stimulate development in some or all of the affected communities (Eklutna, Peters Creek, Birchwood, Chugiak and Eagle River). Concerns were expressed that deviations from approved land use plans 7-2 might occur. Attitudes toward enhanced development appear to vary considerably within the area. Energy Production The APA expressed concern over the effect of proposed with- drawals of water on the existing Eklutna hydroelectric facility's energy production. This reduction in energy production could be the most significant impact of the project. Any alternative that would minimize or delay withdrawals of water upstream from the facility would be preferred by the APA. The APA would also prefer alternatives that involve as little impact as possible on existing structures. Reduced energy production at Eklutna would have to be offset by energy from other facilities to meet APA contractual obligations. The most likely source of energy might be a thermal plant somewhere in the Anchorage area. Thus, there could be secondary effects of the water supply project from construction and operation of a thermal power plant. Water Quality The primary concern over water quality involves disposal of sludge from the water treatment plant. It is unlikely that dis- posal to a flowing river would be allowed. Disposal to Knik Arm might be possible if it is demonstrated that existing water quality would not be significantly degraded. Land disposal would be re- quired if the use of Knik Arm is not feasible. Right-of-Way A considerable amount of public and private land will be crossed by the pipeline. While right-of-way is not a major environmental issue, an opinion was expressed that witholding right-of-way might be used to express opposition to other impacts of the proj- ect such as its possible effects on land use. COMPARISON OF DIVERSION ALTERNATIVES Alternative 1 Alternative 1, diversion from the. Eklutna River and the tailrace of the Eklutna hydroelectric facility, would not affect existing energy production, but would require energy for pump station operation. Existing Eklutna facility structures would not be altered, except the tailrace channel. A new diversion structure would be required in the lower Eklutna River. Prior to diverting river flows, minimum streamflow requirements would have to be determined. Approximately 7 miles of rights-of-way would be required from public agencies between the hydroelectric facility and the Eklutna 7-3 River. Because of geological conditions, special construction techniques might be required, such as pile-supported the pipe, special bedding, cathodic protection, and special pipe joints. impacts during construction would be greater than those asso- ciated with Alternative 3. The treatment plant would be located near the Glenn Highway crossing of the Eklutna River. Discharge of sludge could be either to Knik Arm or to settling ponds. Alternative 2 Alternative 2, diverting water from the hydroelectric facility's tunnel, would provide sufficient head for gravity flow to a treat- ment plant north of the Eklutna Lake Road, thus eliminating the need for a pump station at the tailrace. From the treatment plant south to Anchorage, this alternative follows a route similar to Alternative I; however, no pump stations would be needed because the treatment plant would be at an elevation allowing gravity flow to Anchorage. This alternative requires a high- pressure pipeline. Although Alternative 2 would reduce energy production of the existing facility the most, its total energy requirements are less than either of the other alternatives because no pumping is necessary. Alternative 3 Alternative 3 involves the installation of a pump station at Eklutna Lake and diversion from the lower part of the Eklutna River. The existing hydroelectric diversion structures would not be altered. As in Alternative 1, the flows in Eklutna River could also be diverted, reducing the total withdrawals necessary from Eklutna Lake. There would thus be less reduction in energy production from the Eklutna facility than would occur with Alternative 2. During the summer months, water contributed by the Eklutna River might be less turbid than that from Eklutna Lake. Sludge volumes and treatment costs may be the same as for Alternative 1 and lower than those for Alternative 2. A power line to Eklutna Lake will be required for the pump sta- tion. However, if a lake tap should prove feasible, pumping would not be required. If use of the old hydroelectric dam is not feasible, a new diversion structure would have to be built on the Eklutna River below its confluence with Thunderbird Creek. Min- imum streamflow requirements will have to be determined prior to diverting water out of the Eklutna River. From the Eklutna River south to the Eagle River the pipeline would follow the same route as Alternatives 1 and 2. The pipe- line for Alternative 3 would be 7 miles shorter than for the other alternatives. 7-4 COMPARISON OF ENVIRONMENTAL EFFECTS OF THE EAGLE RIVER DIVERSION AiTD EKLUTNA ALTERNATIVES Table 7-1 lists the relative magnitude of possible environmental effects of a darn and reservoir at Eagle River and of the three Eklutna Lake alternatives. Magnitude is based on the frequency with which concerns were expressed or on direct statements from persons consulted. SUMMARY The environmental concerns relating to natural resources are less for the three Eklutna alternatives than for a dam and reservoir at Eagle River. Potential fisheries impacts are less, and potential impacts on wildlife are much less. While there might be slightly greater fisheries impacts from Eklutna Alternatives 1 and 3 than from Alternative 2, those are not expected to be great. The impacts on water quality and potential effects of water qual- ity on human health are much less with the Eklutna options, than with Eagle River, particularly in regard to sediment and sludge disposal. The old Eagle River dump also poses potential water quality problems for the Eagle River dam and reservoir project. Eklutna Alternatives 2 and 3 would reduce the total energy gen- eration at the existing Eklutna facility. The Eagle River project would have the lower energy requirements than the Eklutna alternatives. Visual impacts are not a problem at Eklutna compared to the im- pacts of the proposed reservoir on the Eagle River. Projects in either watershed would have similar impacts on land use northeast of Anchorage, because water would be provided to this area from both. The Eklutna alternatives would require fewer, rights-of-way and less land acquisition than the Eagle River project. Of the Eklutna options, Alternative 3 requires a shorter pipeline than Alterna- tives 1 and 2. 7-5 Table 7-1 MAGNITUDE OF ENVIRONMENTAL EFFECTS EAGLE RIVER PROJECT AND EKLUTNA ALTERNATIVES Eagle Eklutna I mpact River ATt-.-T--ATt-. 2 Alt. 3 Fisheries Loss of Habitat H L 0 L Fish Passage Facilities H 0 0 0 Minimum Flow Requirements H L 0 L Sediment (from reservoir flushing) H 0 0 0 Requirement for Mitigation of Losses H L 0 L Changes in Microclimate (including downstream temperature) L 0 0 0 Wildlife Loss of Habitat for Big Game Species H 0 0 0 Loss of Habitat for Nongame Species H L L L Management of Pipeline Right- of-Way H H H H Groundwater Shallow Aquifers Near Eagle River L 0 0 0 Water Quality Leachate from Dump H 0 0 0 Septic Systems in Drainage A rea H L 0 L Recreational Use of Watershed H H 0 H Dilution of Existing Sewage Outfalls L 0 0 0 Power Production Effect on Eklutna Hydroelectric Facility 0 L H H Energy Requirements H H 0 11 Land Use Effects on Land Use Options H H H H Location of Treatment Plant L L L L Powerlines L 0 0 L Dam Safety H 0 0 0 Aesthetic Effects Historic and Archeological Sites L L L L Visual Impacts H 0 0 L Right-of-Way and Difficulty of Reservoir Land Acquisition H L L L L = Low H = High 0 = Zero 7-6 ON Chapter 8 ME CONCLUSIONS AND RECOMMENDATIONS Task 5 has demonstrated the technical feasibility of three alter- native projects for developing a 70-mgd water supply in the Ek- lutna watershed. Figure 8-1 rates the three Eklutna alternatives and the Eagle River project in terms of the potential impact of a number of important aspects. The chart suggests that costs ap- pear higher for the Eklutna alternatives. However, -the develop- ment of a water supply project at Eklutna will have considerably less environmental impact than the Eagle River project. Potential delays of the Eagle River project for land acquisition, environ- mental studies, and old Eagle River dump mitigation lead to the conclusion that the Eklutna project can be implemented in a more timely manner. Additionally, inflation effects of such delays could severely impact final construction costs of the Eagle. River project. It is projected that a new water source will be needed within the next ten years to supplement Anchorage Bowl. sources. (The Eagle River-Chugiak-Eklutna area needs a new source of water now.) We conclude that only the Eklutna water source can be developed in time to meet projected Anchorage Bowl demands. The following eight factors were used in ranking each alternative: 1. Capital Costs: The projects were ranked on a straight- line basis.--Pklutna Alternative 2 was rated 10, because it is estimated to be the most expensive ($151 million). A project costing $100 million would have rated 0. 2. Energy and O&M Costs: The projects were ranked on a straight-line basis. _Tklutna Alternative was rated 10, since it is estimated to have the highest costs ($13.6 million per year at 70 mgd). A project with no annual cost would have rated 0. 3. Expected Cost Changes due to design improvements, staged construction, land purchase requirements, and other unknowns and uncertainties: As shown in Fig- ure 6-5, costs could easily be comparable for Eagle River and Eklutna. Therefore, Eagle River was given a rating of 8 to reflect this. Energy conservation and staged construction is expected to improve Eklutna Alternative I the most; it is rated at 1. 4. 1mpact on Eklutna Hydroelectric Project: The projects were ranked on a straight-line -Fai-s-i's, no impact to 100 percent impact. Eagle River has no impact and is rated 0; Eklutna Alternative 2 (tunnel tap) has an average annual impact of 40 percent at 70 mgd, and is rated 4; Eklutna Alternative 3 (lake diversion and 8-1 IMPACT ON FEASIBILITY OF ALTERNATIVES 0 5 10 5 10 5 10 5 10 10 CAPITAL COSTS 6 4 10 .. IF, 4 ENERGY AND 0 & M COSTS 8 6 ........ .. . B 2 EXPECTED COST CHANGES* IMPACT ON EKLUTNA HYDROELECTRIC PROJECT ... . ....... POTENTIAL 4 ENVIRONMENTAL IMPACTS 10 TIMELINESS OF COMPLETION WOM4 RM3 ............ ....... .... 5 6 SUPPLY DEPENDABILITY 7 5 TECHNICAL CONSIDERATIONS TOTAL 36 41 39 50 EKLUTNA1 EKLUTNA 2 EKLUTNA 3 EAGLE RIVER (RECOMMENDED) DAM & RESERVOIR 0 = NO IMPACT 10 = MAXIMUM IMPACT DUE TO DESIGN IMPROVEMENTS, STAGED CONSTRUCTION, AND LAND PURCHASE REQUIREMENTS Figure 8-1 Comparison of 8-2 Water Supply Alternatives river diversion) has an average annual impact of 26 per- cent at 70 mgd, and is therefore rated 3 (the closest whole number). 41ternative 1, tailrace diversion and river diversion, was given a rating of 1 instead of 0 because the operation and maintenance of the Eklutna hydroelectric facility may have to be modified to ensure that adequate water is flowing through the tailrace at all times. 5. Potential Environmental Impacts: The projects were ranked on a relative basis, no impact to the level of im- pact expected at Eagle River, rated at 10. Eklutna Alternative 2 (tunnel tap) was rated lowest at 2, since its only impact is that associated with the pipeline. This level of impact was felt to be considerably less than that of the Eagle River project. Eklutna Alterna- tive 1 (tailrace and river) rated one point higher be- cause of the Eklutna River diversion and tailrace pump station. Eklutna Alternative 3 (lake and river) was rated the highest of the Eklutna projects at 4. The Al- ternative 3 factors that resulted in the extra point over Alternative 1 include: � The pump station at Eklutna Lake (semi- remote) � The power line to the pump station at Eklutna Lake � The change in river flows 6. Expected Timeliness-of Project Completion: As d is- cussed above, the Eagle River-C_h_u_gT_a_R area needs a new source of water now. The Anchorage Bowl is ex- pected to need a new source of water from outside the bowl within ten years. We believe there is high prob- ability that the Eagle River dam project cannot be com- pleted within ten years, principally because of environ- mental and land ownership questions; hence it is rated 10. Ideally, a project should be ready for start of construction next year to serve the Eagle River- Chugiak area. (increased supplies are also needed now in the Anchorage Bowl.) The project that should en- counter least agency and environmental resistance is the Eklutna Alternative 1. Alternative 3 (rated 3) may incur agency and environmental delays because of the work required in and around the lake. Alternative 2 is rated 4, the highest of the Eklutna projects, because of the delays expected from by the U.S. Department of Energy. 7. Supply Dependability: The Eagle River project offers a FeTatively reliable supply and is rated at 5. Long pipe- lines are involved, with medium-length lines going both 8-3 north and south. The dependence of the project on a somewhat complex reservoir operation reduces its overall reliability. Eklutna Alternative 3 has the shortest pipe- line of the three Eklutna projects, about 22 miles ver- sus about 30 miles for the other two. It is rated 5. Eklutna Alternative 2, with 30 miles of pipeline, has very few mechanical features (no pump stations); how- ever, the water supply can be interrupted by loss of tunnel water. It is rated 6. Infrequently the tunnel is dewatered for inspection, for example after the 1964 Alaska earthquake caused debris to enter the tunnel and disrupt the hydroelectric project. The tunnel was dewatered for inspection, cleaning, and repair. Eklutna Alternative 1 is rated the highest at 7 because of the long pipeline (30 miles), because the tailrace pump sta- tion is subject to damage from an earthquake due to poor ground conditions, and because the water supply is totally dependent on the operation and integrity of the hydroelectric project. 8. Technical Considerations: The Eagle River project has many perceived technical considerations, and is rated 9. Many technical considerations are noted in Appendix 11 for the dam, winter operations of the facility, and sed- imentation considerations. Ekiutna Alternative 1 rates a 5 because of the geotechnical considerations at the tail- race and along the pipeline route from the tailrace to the Village of Eklutna. Additionally, the river diver- sion may experience frazil ice and other winter opera- tions problems. Eklutna Alternative 3 avoids the tail- race and pipeline geotechnical problems, but may have similar or worse problems at the Eklutna Lake shoreline. Technical considerations for Eklutna River frazil ice are more important for Alternative 3 because all of this al- ternative's water is diverted from the lower portion of the steep and turbulent river. It is rated 6. Eklutna Alternative 2 is rated 7 principally because of the poor geology and very steep slopes near the tunnel adit. Additionally, this alternative requires very-high- pressure pipe. In addition, the treatment plant for this alternative must be at an altitude of over 600 feet to allow gravity flow to Anchorage. With this rating method we conclude that Eklutna Alternate 1 is the most viable project for the Municipality of Anchorage's future water supply. This project diverts water from the Eklutna hy- droelectric project's tailrace and the lower Eklutna River. RECOMMENDATIONS Task 5 has with limited time and data addressed many consid- erations for a water supply project at Eklutna. Significant 8-4 improvements in the recommended alternative are needed prior to design. Additional studies should be concluded in the near future to ensure timely project implementation. The following areas of study are recommended: 0 Facility Combination. Combining facilities from the Eklutna alternatives and the Eagle River project could result in a more cost-effective project. For example, a nonwinter diversion pump station upstream of the old dump on the Eagle River could reduce energy demands enough to justify its construction. This addition would face less land and environmental concerns than the dam and reservoir project. 0 Revised Population Proi ections. The size and timing of the water supply facilities depend on population projec- tion. New projections should be made. The Municipal Planning Department has indicated that new data will possibly decrease the existing population projections. This would lead to a subsequent reduction in antici- pated water demands. 0 Evaluation of Existin5 Annual Demand Variations. Low, average, and peak demands should be estimated. Once estimated, we recommend that revisions be made in facil- ity sizing to reflect these demand variations. 0 Integration of the Municipal Water Treatment Plant Ex- pansion and New Water Well Plans with the Eklutna Water Source Project. We recommend that Anchorage Bowl projects be integrated with plans for the Eklutna project to allow for staging and timing of construction considerations. 0 Eneroy Conservation Consideration. Pipeline size optim- ization and integration and co nation of alternatives should ma ke the recommended project more cost- effective. 0 Winter Re0ime Studies. An analysis should be con- ducted to determine methods of minimizing frazil and other ice impacts. 0 Geotechnical Investigations. Complex geological condi- tions exist at pump station and treatment plant sites and on pipeline routes. Field data and testing should be conducted during preliminary -design. 0 Water Treatment Pilot Plant. A pilot plant of at least 1-mgd capacity should be operated for 1 year to deter- mine design parameters, to identify potential operational 8-5 problems, and to establish operational and chemical costs. 0 Preliminary Facilities Design. Preliminary plans and specifications should be prepared for the pipeline, pump stations, diversion structures, and treatment plant, along with a detailed cost estimate. The design should take advantage of the results of the recommended areas of study listed above. 8-6 Chapter 9 BIBLIOGRAPHY Alaska Department of Highways, Engineering Geology Section, Materials Division. Materials Site Report, Centerline Soils and Material Site Investigation, Peters Creek to Eklutna. Project No. F-042-1(7) - (A06022). June 1971. Alaska Power Administration, Department of Energy. Operations records of the Eklutna Hydroelectric Project. Alaska Power Administration. Hydroelectric. Powerplant Sitin in Glacial Areas of Alaska, Prepared by D. L. Shira. Juneau, Alaska. Anchorage Planning Department. Eagle River - Chugiak-Eklutna Comprehensive Plan. 1979. Anchorage Water Sources. Prepared for Anchorage Water Utility Central Alaska Utilities. Anchorage, Alaska: Tryck, Nyman & Hayes; Dames & Moore; and Leeds, Hill & Jewett. December 1973. Cook Inlet Aquaculture Association. Requests for proposals to design and construct the Eklutna Salmon Hatchery. October 1981. Douglass, J. C. Eklutna Project, Appendix B, Water Supply and Power Generation. Anchorage, Alaska. July 1948. The Eagle River Community Water Supply and Distribution Plan. Anchorage, Alaska: Quadra Engineering. 1977. U.S. Army Corps of Engineers, Alaska District. Metropolitan Anchorage Urban Study, Volume 2, Water Supply. Prepared for the Municipality of Anchorage. 1979. U.S. Bureau of Reclamation, Alaska District Office. Eklutna and the Alaska Earthquake. Juneau, Alaska. 1966. U.S. Bureau of Reclamation. Eklutna Dam, Powerpland and Tun- nel, Technical Record of Design and Construction. Denver, Col- orado. March 1958. Friction Factors for Large Conduits Flowing Full. 1977. Rehabilitation of Eklutna Project Features Following 1964 Earthquake. A Supplement to Eklutna Dam, Tunnel and powerplant, Technical Record of Design and Construction. Den- ver, Colorado. June 1967. 9-1 -------. Eklutna Water Supply. 1950. U.S. Environmental Protection Agency. Estimating Water Treat- ment Costs, Volume 1, Summary. EPA-600/2-79-162A. Municipal Environmental Research Laboratory, Office of Research and Devel- opment. Prepared by Culp/Wesner/Culp Consulting Engineers, Santa Ana, California. August 1979. -------. Estimating Water Treatment Costs, Volume 2, Cost Curves Applicable to 200 MCD Treatment Plants. APE-600/2-79-162B. Municipal Environmental Research Laboratory, Office of Research and Development. Prepared by Culp/Wesner/ Culp Consulting Engineers, Santa Ana, California. August 1979. U.S. Geological Survey. Preliminary report on Water Power Re- sources of Eklutna Creek, Alaska. Prepared by Arthur Johnson. Tacoma, Washington. August 1947. 9-2 I I Exhibit A Transmission Pipeline Criteria No Exhibit A ME TRANSMISSION PIPELINE CRITERIA Certain criteria were used in the preliminary design of the pipe- line route from the Eagle River to the Municipal Water Treatment Plant in Anchorage (Appendix IV, Transmission Main Design). This exhibit is a summary of some these criteria as they relate to the proposed pipeline routes from an Eklutna Lake diversion to the Eagle River. VELOCITIES The minimum velocity for untreated water is recommended to be 2 feet per second (fps). No minimum velocity is required for treated water. The maximum velocities should be held to 5 to 7 fps except for that section of the pipeline from the diversion point to the water treatment plant. A higher maximum velo *city in this section of the main may be required in order to meet the minimum desired velocity during initial flow conditions. PRESSURES The pressures in the pipeline may vary from 15 to 355 pounds per square inch (psi), depending on the alternative project se- lected and the operating flow condition. Alternative 2, diversion of water from the Eklutna Lake tunnel will involve high heads of up to 355 psi in order for the water to flow by gravity to An- chorage. Numerous pressure-reducing stations will be required along the pipeline for the distribution systems connecting to this supply main. The alternatives whereby water is diverted from the Eklutna power plant tailrace or the Eklutna River were tentatively de- signed so that the pressures between the communities of Eagle River and Eklutna would range f 'rom a minimum of 40 psi to a maximum of 120 psi. Thus, the pipeline would provide for normal service without the addition of numerous pressure-reducing sta- tions to the various distribution systems served by the main. FRICTION LOSSES A Hazen-Williams coefficient "C" of 120 will be used to size the pipelines. Friction factors for the Eklutna Lake tunnel were de- termined from 1960 field measurements (U.S. Bureau of Reclama- tion. Friction Factors for Large Conduits Flowing Full. 1977). The tunnel'is -@-3-,550 fJe-t fo-n-g a n-d-79--fe-et -Tn-cri a meter, and is concrete-fined. Figure A-1 shows the relationship between flow and tunnel head loss. A-1 FRICTION HEAD LOSS (ft) 0 c 0 z o.. 0 m 6 0 0 0 > Tc ->3- 00 ?. z, 5 "o" -C) m m z 5n ,;c :i co --I M MOCD(D z m 0,7.< 5 0 0 @? 0 z 0) m M, > 3 Z o r- Z 'o 'En 0 0 m -n r r- CL rm 0 m -PEAK POWER FLOW 0 SURGE ANALYSIS No surge analysis was made during the preparation of this report. For the purpose of selecting pipe classes, a surge allowance of 50 psi is assumed. During the preliminary or final design of the selected alternative, a computer analysis of the surge conditions will be required to solve the hydraulic transient problems. EXTERNAL LOADS AND RESTRAINTS Alternative pipeline alignments from the Eklutna hydroelectric facility to the Eklutna River must be designed to withstand live loads from trains. Concentrated pressures on tunnel liners and casing should be calculated using Cooper E80 loadings. ADDITIONAL PIPELINE DESIGN CONSIDERATIONS In evaluating the costs of the various alternatives, the require- ment for pipe access manholes, isolation valves, blowoff/drain valves, and hydrostatic testing must be considered. This task does not include evaluations of the existing adit tunnel of the Eklutna Lake tunnel and the old Eklutna River diversion dam and tunnel. However, some assumptions have been made so that an order-of-magnitude cost estimate can be made of each alternative. No geotechnical investigation or corrosion survey has been made on that section of the pipeline from the Eagle River north to the Eklutna hydroelectric facility. For the purpose of estimating costs, it has been assumed that all the pipeline from the Eklutna River north to the Eklutna hydro- electric facility will require an impressed-current cathodic protec- tion system. Approximately 25 percent of that section of pipeline between the Eagle River and the Eklutna River will need an impressed-current cathodic protection system. During final design, a corrosion investigation should be performed on the selected alignment. The study would include soil resistiv- ities, chemical analysis of the soils and water, measurement of stray electrical currents, and recommendations for the design of a cathodic protection system, including pipe coatings and linings. A-3 I I Exhibit B I USGS Water Quality Data U"IITFr) STITES r)FPA,-'T'4PNT OF IMTFRIM4 - r-POLnGICAL SUPVEY PW)LESS f)ATE 09/;39/'@ l':1?P000() - EwL!)Tt)A C NP PALMFP AK 1115,TPICT C01"@ 0? 4ATFR ')IIALTTy nATA SPF- CIFIC CARBON STRF!o4_ COLOP CON- DIOXIOE ALKA- FLOW, (PLAT- DUCT- DIS- LINITY S11QFACF STREAM- INSTAM- T NUM ANCE: PH SOLVED (MG/L rTMF APrA F LOW T ANF01 IS COFALT (H 1 CRO- FIELD (MG/L AS P @@TF (SO MT) (rrs) (CFS) i.01ITS) IIHOS) (UNITS) AS C02) CACQ311 W049) (Ono6l)) (ooO61) (oooAo) (r)()n9r-) (00400) (00405) (00410) nCT 9 1048 19 ... 11511 119 1?6 117 45 iq ... Q'I C.; 119 1 Pf, 214 90 APR . 1049 2?-2n 119 ill 113 7.1 718 50 "Ay OP-31) 119 116 110 7.1 7,8 so JIM 01-?0 119 362 14? 7.1 8.0 52 J1,11- 01-?Q 119 817 11171 7o2 6o2 so AIJGj 01-20 119 926 I'M 7.1 7o2 47 SFP 02-311 119 6A0 178 7.n 9.0 46 OCT 03-31 119 185 125 6.9 11 44 "Ov 04-?Q lip 12? 1?7 7.0 8.6 44 r)Fr: 0?-3f, 119 133 lin 7*5 209 48 JAN 9 InqO n3-1() 119 133 114 794 3v8 48 FF@i 03-?7 319 125 138 7.7 2*0 51 r4AR n3-v 119 120 11A 7.7 290 52 APR nl-?P 119 109 5 134 7.2 7ol 57 MAY nl-?O 119 94 5 l?A 7.4 3,8 48 JUN OP-3f, lip 349 5 11c) 7.6 2*3 48 Jul, n3-31 lip 976 10 12A 7.6 293 48 At 16 04-?" 119 877 10 liq 7*5 297 43 ,;Fp k ol-;>rl 119 472 5 1?4 7.1 6*9 44 DFC 01-?r- lip 126 5 jl(, 7*0 9o4 48 I IN IT p7 ST t TFS "VP A qT "rt,]T OF T N'TFPT OR OL.()(; I CAL C U VLY PROUSS OAtE 09/29/81 S 192A0000 - FKI-I)T"IA C '1P PAUAH4 AK DI1)TPICT C09F o2 WATFP 011AI ITY DATA NITRO- sonlum+ GFN WARD- MAGNE- POTAS- CHLO- NITPATF HARD- @ IESS , C AL C I I IP Slum, slum RTPF9 RM:ATc' CAP- n I S- ?JFSS NONC AQ- DIS- DIS- DIS_ U 15- ('Arli- RON A TF SOLVED (mr,11- RONATE SoLVFr SOLVED SOLVED SOLVED @@ S (MG/L (MG/L AS (MG/1- (M,;/t- (MG/L (MG/L (MG/L r) T P @4C)3) AS COI) AS M CAC01) r[AC03) AS CA) 61; MG) AS NA) AS CL) (nO440) (00445) (00618) (0090n) (()nc)n?) (nn9lq) (00925) (00933) (00940) nCT jn4P I P 59 0 .14 c;6 2.6 5.8 1.0 IQ... lin f) 25 - .5 APR , 1049 22-PQ 0;1 0 .09 64 14 19 3.9 192 .8 ?A4y 02-3n 61 n .19 6? 12 19 3.5 lee .9 JUNI 0 3-;) 1) 63 n 020 64 13 20 3.5 2*5 101 JOL nj_;@q 61 *16 6;) 12 20 3*0 2,8 160 IN L 1(7 0 1 - S 7 0 .20 C;p 12 1 F% .1.3 2.8 .6 02-3n C;6 n .14 Sp 12 18 3.o 2*8 .9 OrT 01_31 S4 0 .18 C;p 14 Is 3.2 1*6 1.2 rinv 04-pn r )4 n .16 98 14 IR 3.1 2,3 1.0 r)F(- 12-3n 5A n 018 9A 11 19 2*6 393 .9 J A'4 9 1090 0 i- 11) .16 0; 2 13 2 n 2*9 2.0 Is FFP 03-?7 0 o20 1@c; 14 3.1 200 .9 @qr,w n1-31 Al n 11 2n 3*1 3.7 *5 A W1 70 0 lq 74 17 24 3.5 194 1.5 "Ay 9c) n (,6 18 P 1 3.3 101 1.5 ji p; 02-3f) 99 0 .01) 63 15 19 3.8 1.9 1.1 J, J1_ C;6 9 1 A 2.8 4*3 .9 04-29 n .00 SI in 16 3.2 3*5 .9 5;7 n k nl-;),; S4 n .01) 61 17 2n 2.8 2.1 .4 F 1, Sq A? 14 2n 3.0 108 .5 11NITFI) STATES @)f_-AQT'AFmT 1@- INTMOR - (-4 OLOGICAL S1114VEY PROCESS OATE 09/29/81 152Rnooo - F'@I@')Tp,jA C ')P PALMEP AK OISTQICT CODE 02 'WER QIJALITY nATA SOL I Dq , N I TRO_ FLO()- SILICA, SUM Or SOLIOS9 SOLIDS, GEN9 ELEV, Sul.rATF Rlf)Fq DTS- CONSTI- 01S_ OIS- NITRATE OF LAND pyci- Dis- SOLVED TUFrJTsq SOLVFD SOLVFn DIS- SURFACE !101-.VFn @;OLVFD (MG/L PTS- (TONS (TONS SOLVED IRON DATUM ("@',/L (MG& AS SoLVFr) prp PER (MG/L (UG/L (FTo r) A TF AS q04) AS F) ST02) (MG/L) DAY) AC-FT) AS N03) AS FE) NGVD) Wc)45) wqw (On955) (7o31j) (7,1302) (7030) (71851) (71885) (72000) IrT 1048 119 po 3oO 78 26.5 oll .60 856,53 19 ... 6o4 Isl 856o53 '@nQ 9 IQ49 22-pQ )4 3oO 72 21005 .10 040 856,53 A y o,J-30 )3 .1 2.8 7? 22,6 oin 080 856.53 JON 03-2n 16 3.5 7S 71c,,2 oil .90 856o53 JUL n 1-;)c) 16 3o3 77 17o In o70 856o53 AUG nl-2c) 16 3.8 74 isr, In 090 856,53 SEP 02-3() 15 2eg 71 13n sin *60 856,53 nCT n3-31 is 2.4 69 34oS nQ 080 856,53 Nov n4-?Fl 16 2.8 7 0 23.1 10 *70 856,53 DEC n?-I@ I C; 3og 74 2A o 6 In 080 40 856953 JAN 9 1 Q S n 03--An 15 1? 4ol 7c; 26.9 oin o7o 40 856.53 FF(4 n3-P-7 16 .1 5.n 79 26.7 .11 .90 30 856.53 "AF? 03-11 17 .1 5o9 A? 26.6 .11 o7f) 20 856,53 APQ 13-?0 1 f, .? 3*7 H6 ?c;. 3 .12 080 20 8S6.53 4 1k. y 0 1 - p') 16 o;? 3.9 7@ 1915 o 1 t) 080 20 856,53 JUN 0 2-:10 17 .0 3o6 76 71.6 In o4o 100 856.53 J[it_ 0.3-11 16 .0 3o4 7r, 198 In o50 100 856o53 plj(; Ab_?Q I S 00 2o6 161 o40 100 sc;6153 c Srp % 0 1 _;@C; pr) on 3.4 76 9A.9 In .40 70 856.53 rEr -11 -;>e, 76 3.P 74 29.2 .10 *50 40 856. 9 1 @11'11TPI) STATFIS, DEP.ARTMF@IT Or INTERIOR - rVOLOUICAL CURVEY PR',)CESS DATE 09/29/kl 1'32PonnO - FKj_UTNjA C 'M PALmFP AK DISTRICT CUDF 02 4ATEP QJ)ALITY DATA SPF- CIFIr CARBON STREAM- COLOR CON- DIOXIDE ALKA- HICAR- TFN!PFP- FLnW, (PLAT- DUCT- DIS_ LINITY BUNATE /%TIIRF9 SuRFACF STREAM- INcTANI- TNUM ANCE PH SOLVED (MG/L (MG/L T T MF_ OATFP APEA FLOW TANFOIJ!; COPALT (MICRO- FIFLD (MG/L A S AS n A TV ((,Fr, C) (SO MI) (CFS) (CFS) I IN I TS) MHOS) (UNITS) AS C02) CAC03) HC03) (orinl()) (Pon4g) (Or)060) (n0061) (nooSn) (ono9c;) (on400) (00405) W410) (00440) J'A Iar@l nl-?q 119 122 5 I.-3A 7.1 746 49 60 .FrP ()?-?() 119 71 5 116 7.4 3.8 49 60 M A r? n;1-7%0 119 56 ci 137 7,4 3e9 50 61 APP op-in 119 49 c; IP9 7.6 2.3 46 56 kA. A y 04-PR 119 46 5 114 705 3.0 49 60 J! IN nl-Iq 119 357 5 IpFt 7.3 4,6 47 57 In-?Q 119 369 5 126 7.4 3o6 46 56 JOL n?-i6 119 1240 5 I?_1 7.3 4o3 44 54 119 1350 5 110 7.3 398 39 48 Al IS ni ... 1000 13,0 IIq 99Q 5 In9 7.3 4*0 41 50 n #; ... lonn 13.0 119 9sn 1 107 6o6 20 41 50 C,; r P pc@ ... 119 5IR 5 116 6*6 18 38 46 fl()v Pri ... 1430 111) 5 IP? 7.4 3.6 46 56 nrr 27, 119 10 1 7.6 2.3 48 58 JA@! o PQ ... 15no 20 11 Q 0A 10 1;!4 7.5 2*8 46 56 Frn Innn n 119 lip 5 jpc@ 7.5 2o9 48 58 PIAP 1 1... 1100 .5 1?0 C; 1?1 7.2 5.5 44 54 ,@Dp I 11@ ... 11,30 .5 liq 4P 5 1;) 1 7.2 Se4 43 53 A y 14011 ct. 5 119 5 111) 7.4 3.4 44 94 in ... 19nn liq Inn 5 lp6 7.6 2.4 49 60 141n IIQ 5 121) 7.5 12 39 48 jron I o.c; IIQ 4F%4 5 lip 6. Ft. 12 39 48 WITTFn STaTES OEPARTNIF@'T ()r INTFRIOR - rFo(-')GICAL 1;UPWy PROCESS UATE 09129181 152Pnnno - Fv1.lJTl`1A C '@P PALMEr JtK DISTRICT CIDE 02 WATrR 011ALITY 04TA l"TTPn_ SODIUM+ rF No HAQD- fAA(;KJF- SODIUM POTAS- POTAS- NTIPATF HARD- NESS CALCT11M S I 0M 9 SODIUM. AD- SIUM slum* rpD- n T NESS N01`4CAP- Dis- n L DIS- SORP_ DIS- DIS- Rfl@'ATE Sf`OLvF0 (MG/L RONATE SOLVFn SOLVED SOLVFn TION SOLVED SOLvEci ("'GIL p4r./1- AS (MG/L oirvi- I tA(-11[_ (MG/L RATIO SODIUM (MG/L (MG/L n A rF AS r.()I) A", IND CAC03) CAC03) AS CA) AS MG) AS NA) PERCENT AS NA) AS K) (00445) (01`11"118) (tringnil) (on9op) w9lq) (n09;)`5) (0093n) (00931) (00932) (00933) (00935) 1951 p o14 6P 13 20 2.9 3*7 Fvn n?-?6 0 .2() 63 14 20 3.1 2o4 I'/AP _np-In n '?n 62 12 20 2oQ 3.2 Arp n?_io 0 6?5 6n 14 19 1*1 1.8 MAY n4-PA n o;30 64 19 2n 3,5 1.4 jj loo ni-is n 65 111 20 3,7 6 1 .11 63 17 Iq 3.7 1*7 -it n?-I(, 0 *14 99 is is 3.4 2,0 ?n-3n n .()9 53 14 16 1.2 2.o lk I Ir, n -4 ... p; .1A Sp. 11 16 2.9 Sol 605 so 9 16 2,5 4,7 S F P oil SS 17 is 2.4 6 n... .14 56 10 18 2.6 4.2 F)FC *16 511 11 19 2.7 4*8 @IAKI o C) c;;@ 21, ... 1) .14 62 16 19 316 7 F F r, ;)n ... n oil 6? 15 19 3.6 3,2 k4 Ap 11 ... 0 14 19 2,6 2.8 A Df) I Or- . . . A .11 93 10 17 6 4,0 @ Y ng 5A 13 19 3*1 3.6 in ... n *14 673 14 2n 3ol 3.7 ..lilt n .14 59 13 19 2.9 3*6 I Ir .?9 c; 1 12 16 2.9 ion .1 7 .9 WITT17f) STATES DEP.@PTArt!T OF INTFPTOR - rXOLOGICAL SURVFY PROCESS DATE 09/29/81 15?.AfIn0n - FKLI-)T'JA C JR PAL;4FP AK nISTRICT CODF 02 WATrQ 111iALI TY UATA SOL I DS, SnLins, NITRO- C14LO- FLUO- SILICA* RFS I Ol IF SJJ'4 OF SOLIDS9 qOLIDS9 GEN9 ELEV. P T r,,F , ';I)I-FATE RME9 0 1 S- AT I-In CONSTT- DIS_ DIS- NITRATE OF LAND ,')IS- nTc- DIS_ SOLVED DFG. C TiJENTS, SOLVFD SOLVED SURFACE Sr)LVEh SnLVFD SOLVFn (MG/L DIS- D1S_ (TONc; (TONS S rO) LI SV @ D IRON UATUM ("WL (Mr-/L (4G/L AS SOLVFr) SOLVED PFR PER (MG/L (UG/L (FT* nATF AS CL) AS 504) AS F) S102) (MG/L) (MG/0 DAY) AC-FT) AS N03) AS FE) NGVO) ((W)4n) (nIQ45) (nng9n) (OngSS) (7o3On) (70"Inl) (7o3n7) (7003) (71851) (71985) (72000) 1991 nj_?q pi is 11 3,3 79 26.n oil *60 30 856,53 FF',n n;,- 76 1 0 n 16 3.0 76 14.6 6 in 090 40 856,53 HAP np-40 Ion 16 3.? 79 77 1109 oil 090 30 856,53 App np-io .5 16 4.0 7A 73 1001 *10 101 40 856.53 @'A Y 04-Pq A 16 4ol 76 9.44 .10 690 70 856.53 jl IN ni-fe; Jac; 16 .2 Sol 76 76 73.3 *in o40 30 856.53 10-29 2.n 16 .2 4.3 75 74,7 *10 050 30 856e53 JI 11- np-)6 2.0 1c; 4.3 79 72 265 oil o60 60 856.53 ?n-10 P.;, 14 4,6 66 241 .09 940 40 856,53 AIM 1)1... 2,@ is 511 74 2oo *in *80 856,53 ... Ion 17 6.1 72 185 010 .20 856,53 PC; ... 2.2 14 91 3.5 7;; 64 105 .10 050 10 856,53 Nnxt ;" ... 2.5 14 .1 3.3 7;) 7.1 29.9 oin 960 60 856.53 nFr ;,)7... 3.r, 1c; .1 3.2 76 78 ?7.9 010 070 110 856.53 j A Vi 195? 16 on 3.1 6f, 71 24.6 009 60 30 856.53 F F r, ?n J.r) 1A on 3,2 7c; 78 23.9 .10 050 10 856,53 KA @;) 0 ... ?an 16 .0 2.8 71 72 23.n 010 *50 20 856,53 APP 10;... 1.7, 11 .1, 2.6 7n 69 9.07 910 .50 10 856,53 'AAY p 19 an 21.9 74 7,1q 010 940 40 856.53 17 3.3 Ek 0 21 . 0@ all s60 20 856.53 rl .1 ... ?.7 113 an 2.7 76 149 010 *60 30 856,53 A J,r, 2.9 66 72.n 009 1*3 39 856,53 I . 5 1 C; 'JNJTTFn STATES bEPAkTmF'PoT OF INTERIOR - @'-FOLOGICAL SURVEY PROCESS JATE 09/29/81 0@1P23ri141013200 - FIVE MILE r Ar F-KLIITNA LK NR EKLUTNA AK DISTPICT CODE 02 WATEP 011ALTTY DATA S"r- NITRO- CTFTr CfjR80'-A GEN9 HARD- 0 t, 6!:z 'oNj_ DIOXIPE ALKA- HTCAP- NITRATE HARD- NESS9 CALCIUM (Pl- r- Di irT- OTS- L I N I Ty qONATF CAR- NEss NONCAR- DIS- DIS_ I KJ @j A'JCE PH SOLVEO (MG/l.- (M(j,/L BONATE SOLVED (MG/L BONATE SOLVED CtIRALT (!4TrRO- FIELD (MG/L as AS WGIL (MG/L AS (MG/L (MG/L fl TV I VNI T T 5) ".141s) (UNITS) AS C02) CACOI) HC03) AS COI) AS N) CACOJ) CAC03) AS CA) (onoAn) (ono9r;) (On4OO) W405) (on4ln) (n0440) (0044r-) (00618) (00900) (00902) (009151 -@y , 19 C;,3 nj..* In 219 7,4 7.n on 110 932 114 24 3o !JNITFn STATES 0EPr%PT,14FNlI OF INTEPIOR - rFOt-o(:ICAL SURVEY PROCESS DATE 09/29/81 Al?P3S149011200 - FIVE 71ILF r. AT EKLUTNA LK NL? FKI-I.JTNA AK DIST14ICT CODE 02 WATER QUALITY DATA sOLIDS9 NITRO- KA A rNF- 1300TUM POTAS- CHLo- SILICA9 SUM OF SOLIOS9 GEN9 @;Itl 4, c,0r)Tl_J". Af)- ellumo 9Ir,)Eq SULFATF nis- CONSTI- DTS- NITRATE r) T;- nTq- SORP- I)IS- [)Is- r) I S- SOLVED TUENTS9 SOLVED DIS- ';(JLVF'") rinf- k/En TTON SoLVFf) SOLVFD SOLVFn (MG/L DIS- (TONS SOLVED 00('1/1- ('ir,/L RATIO SODIUM (MG/L (MGIL (MG/L AS SOLVED PER (MG/L r)ATc' 45 ms) Al@ NA) PERCENT AS K) AS CL) AS S04) S102) (MG/L) AC-FT) AS N03) (onq?5) (o 0c),30) (an9jj) (on932) (nog3S) 0 nq4n) (00949) (no955) (70301) (70303) (71851) y 9.1 3.6 .1 6 I.o n 30 509 135 118 194 IJNTTFn STATFS ;)Ff)fWT:-!v@.,T nr INTFRIO14 - ',F')L_0(,ICAL SURV@ Y Pq0CFES5 OATE. 09/29/81 AIPIPqI490 31?(.)f) - T-Wf:@_r '411-F C AT @@Kj_[JTNA LK FKLIJTNA AK DISTRICT CODE 02 WATrP 01JALITY nATA NITRO- CTrTC CARRON GEN9 HARD- r (i i *r) r? (-r)Nj- D 10 X I D E ALKA- ATCAR- NITRATE HARD- NESS* CALCIUM (Pt_ A T nlIrT- r) I S_ L If,J I TY RONATF CAR- OIS- NESS NONC AR- DIS_ 7 @jj 1@4 jWrE PH SOLVFr) (mr,/L (mG/L n0NATF SOLVED (MG/L HOKIATE SOLVED CO@IALT (MTCPn- FIELn (MG/L rA S AS (Mr,/L (MG/L AS (MG/L (MG/L n,%Tr I TS) mwns) (UNITS) AS C02) CACOI) HC03) AS C01) AS N) CAC03) CAC03) AS CA) (no()Pi) (nnnQ5) (on4no) W409) (on4ln) (00440) (00445) (of)618) (00900) (00902) (00915) 1 26.4 7.7 4.5 11 C; 140 .3A 138 23 34 1),IJTTFF) STATES @)Ei-'ARljlr@,T OF INTFRIOR - rF,)L0GIcAL SURVEY PkUCFSS UATE 09/29/Pl f,j?3?9j4')njj?or) - THREF MILP C AT EKLUTNA LK @;rl F.KLUTNJA AK DISTRICT COOF 02 WATER QUALITY DATA POTAS- SOLIDS* NITRU- CHLO- SILICA9. SUM OF SOLIDS* GEN9 sTlr4. sonuw, AD- SILIM, RIDEs SULFATE DIS_ CONSTI- DTS_ NITRATE r) T q- 0 T cz- qr)RP- 015- n I S- DIS- SOLVED TUENTS# SOLVED DIs- SOLVEn S0l_VFn TION SOLVFD SOLVED SOLVED (MG/L DIS- (TONS SOLVED (MG/L (mr/L RATIO SOnlum (MG/L (?'('7/L (MG/L AS SOLVED PER (MG/L r) A TF7 AS 1-*r,) AS ., NA) PERCENT AS K) AS CL) AS S04) S102) (MG/L) AC-FT) AS N03) (()nq2g) (n 0 f)3()) (0r)911) (Oo932) (oo93c;) (0094n) (0094r@) (00955) (70301) (70'4n3) (718si) m 11 y I Qc;3 12 4oS 7 n 3 n 60 159 .22 1.7 111,17TFI) STATF, !)FP414T'!r-r,T Or TkITEPInq (;VnLnGICAL smVEY P,4:-)C;7SS UAIE 09/29/81 f,1?701j4q-;,PoPon - Fl<L'JT'4A P @T rq.F7NM HWY AT FKI UTNA AK OISTRICT C001@ 02 WATEq ()iiALTTY ;)ATA SPE_ NITRO- CIFI,^ CARHO4 GENt STPrAM- COLOP CON- nIOXTDE ALKA- BICAR- NITRATE HARD- T@-P'PFP_ FLOW, (PLAT- DUCT- r)ls- LTNITY BONATE CAR- DIS- NESS ,'TIIRF. INSTAN- INUM ANC_@_ PH SOLVFr) (MG/L (MG/L 80NATE SOLVED (MG/L T T 1-1 '@TFP TANFOUS cnRALT (MICQO- FIFLn (m(',IL AS AS (MG/L (MG/L AS n(jF (Ilrr r) (Crl;) UNITS) MHOS) (iiNJTq,) AS C02) CAC03) HC03) AS C03) AS N) CAC03) (C-OnIO) (000051) (r)nn8n) (00099) (no4no) (00405) (n0410) (00440) (00445) (oo618) (oo9oo) IQ49 ?4 ... I 7?n A 574 161 f, . Pi 2o 63 77 0 .27 79 -ili" 9 11)1;1 11.9 323 5 )67 6.9 is 62 76 n .16 77 'J'lTTFn STATES DEPARTHFNIT Or INTEPIOP rFOI.OGICAL SURVLY PROCESS DATE 09/29/81 A127011497?0800 EKLUTN@ P AT GLENN HWY AT PKLUTNA AK DISTRICT CODE 02 WATFP QUALITY nATA SODIUM+ SOLID59 NITRO- H,@ P I)- MACNF- POTAS- CHLO- SILICA9 SUM OF SOLIDS9 SOLIDS9 GEN9@ tlrrS, tll.rTll- SIUM9 sitim RIDFq St!LFATF DIS- CONSTI- DIS- DIS- NITRATE @'Oqc t P_ T f nTc;- nTs- Ols- nIS- SOLVED TIJENTS9 SOLVED SOLVED DIS- PONATF ';()LVFn SOLVED SOLVED SOLVED s0LVFO (MG/L Dis- (TONS (TONS SOLVED IRON (vr./L ('Ar, /L (MG/L (mG/L (MG/L (MG/L AS SOLVED PER PER (MG/L (UG/L ,)ATF r AS NA) AS CL) AS S04) S102) (MG/L) DAY) AC-FT) AS N03) AS FE) Arr)3) (,A) AS MG)) (onon?) (00Q25) (00933) (00940) (0094c;) (00955) (7n3ol) (70o2) (70303) (71851) (71885) J11H , 1949 ;)4 ... 1 3 5.2 2sS Io4 18 4.9 94 146 *13 1.2 JON 9 1051 oor ... 15 pi 4.7 3.4 I*n 19 4.3 94 8290 *13 070 30 WITTrf) STATES 0EP,@RT'Irf\fT ')r INTFPfOR - rF0[_0GlCAL SURVEY PH0CFSS OATE 09/29/81 61P7A0@j4qjQ9000 - FKLIJIN1. C PL F-(LHT@!A OTVFqST(1'4 nAm Np PALMER AK DISTRICT CUUE 02 W A T(7R OfIALITY DATA .,Pr- NITRO- CIFIC C ARRON GEN t HARD- rot-Op CON- Dr0xrnF ALKA_ RICAP- NITRATE HARD- NESSs CALCIUM TEYPFP- (pl'AT_ DUCT- DrS- LTNITy PONATF CAR- r) I S- NESS NONCAR- DIS- ATIIRF* TN'I)M ANCE PH SOLVED (MG/L WG/L RONATE SOLVED (MG/L BONATE SOLVED VI P, T P R rf) r-l AL T (MTCPO- FTELn (MG/L AS AS (MG1L (MG/L AS (MG/L (MG/L P P@ TF (n-6 C) I It-! I TS) MHOS) (UNrTS) AS COP) CAC03) HC03) AS C03) AS NJ CAC03) CAC03) AS CA) (omnln) (onnolo) (Oon95) (on4oo) (00405) (n 0 4 10) (00440) (00445) (00618) (00900) (00902) (00915) APP . 194q P?.?ol 145 7.1 %1* 1 7 69 0 .20 70 13 21 0 Ay 15A 7.6 3.1 63 77 0 .18 76 13 23 il l" nl-pn 146 7* ci 3.4 S6 ('8 0 .18 70 14 P2 J, )I- () I -P0 140 7*3 5*1 92 63 0 .16 64 12 20 Allri nl-?9 136 7.n 919 51 62 0 .14 64 13 20 i0e.. iles IA7 7*1 17, qo qp 0 93 13 sFc, 02-nc) 131 7.1 7*5 48 59 0 .14 61 13 19 nCT 10-31 146 792 70 c37 69 0 .18 70 13 21 @)Ov n4-79 148 7*3 5. 7 98 71 0 .16 72 14 2? r,Fr 0?--40 14A 7.5 395 t; 7 70 0 .16 71 14 22 JAN , lgqn t)7-10 19 2 7.6 ?09 99 72 0 .16 71 12 22 F F. R n3-27 151 7.6 ?.9 c;8 71 0 s14 71 13 22 MAD () I- I I - 15 150 7.8 1.6 5.1 65 0 .18 73 20 22 @)p n -.I-?n C; 193 7.7 2.4 62 71@ 0 .18 73 11 22 "AY I _pQ 160 7*7 P . 6 66 Al .20 go 14 23 C; 1 E;o 7.7 2.3 r, A 71 0 .23 75 17 23 C; 129 7.4 3.6 46 56 0 .14 56 10 18 n4-11 1?1 7.4 3.4 44 54 0 .16 57 13 17 nl--Pq 13n 7.7 1.9 48 99 0 *11 51 3 16 nCT I n 5 144 7.7 2.2 56 69 0 .11 65 9 20 r)l-;)7 1; 141 7.7 2.0 92 63 0 14 61 9 19 WITTFn STATFI, ()FPA0TAFrjT r)F INTEPIOR - (-,FOI-OGICAL r SURVEY PRUCESS UATE 09/29/81 A127061491Qq000 - EKLUTAA C PL FKLIJTNA DIVEQSTON DAM WR PALMER AK DISTRICT CODE 02 WITFR QJ)ALTTY DATA S0')TU%4+ SOL I DS 9 SOLIDS9 NITRO- AliKIF - PIT %r,- CHLO- F1-UO- SILICA, RF S I DUE SUM OF SOLIDS9 GEN9 1; 1 U A R IDE SULFATE QIDE, nis- AT 180 CONSTI- DIS- NITRATE n T S- r) T S- DIS- OTS- [)Is- SOLVED DEG, C TUENTS9 SOLVED Dis- (TONS jOLVEn SnLVFD SOLVED SOLVED SOLVED (MG/L DIS- DIS- SOLVED IRON CIAGIL (MG/L (MG/L (MG/L AS SOLVFD SOLVED PER (MG/L (UG/L r) T`F AS 04G) At; NA) AS CL) AS S04) AS F1 1; 1021 (MGIL? (MG/L) AC-FT) AS N03) AS FE) M'1271) (0r))31) (0094n) (On945) (0095ni (n0999) (70300) (7o3ol) (70303) (71851) (71885) Ar)p 040 2@--q 4.4 1.2 .5 15 3,5 -- 80 .11 .90 -- @4AY np-In 4.; 2.1 .8 15 .1 4.6 89 .12 .80 J1 F\I nl-pn 3-6 1.8 1.1 16 -- 4.2 83 oil oso nl-?q 3.4 2*Ft .9 16 3.8 79 ell *70 Al IC, n1-29 3.4 P*3 .7 16 4.2 78 ell *60 19 ... -- -- -- -- -- -- -- -- -- -- -- SEP nll-r),) 3.3 2.3 .5 16 3,8 75 sio *60 r)rT 1-31 4.2 2.3 19 16 4*2 83 ell 680 Nov n4-;'R 4.? 1.8 .9 16 3.7 84 ell *70 -- n F r, np-In 3.q 2.3 .8 16 .1 5.7 86 e12 o70 40 JANJ . 1915n 0-3n 3.Q 3.7 110 17 .1 5.3 89 *12 *70 60 FFO nl-p? 1.9 2.7 *9 16 *1 4.9 86 o12 .60 30 H@p ()i-ll 4.4 1.3 lo9 la .2 5.8 -- 86 .12 *80 30 '@PQ nl-?9 4.q 4.c; 1*6 17 .1 5.1 91 93 o12 *80 40 Ay ()1-?9 5.4 2.6 1.6 19 .1 A.4 -- 95 s13 *90 30 jw-l n P-jr) 4.P .6 1.6 14 4.9, 84 .12 1.0 40 j1 11 ni-ps 2-f, 4.1 1.1 16 3.4 73 .10 o6o 70 A I I '"@ ()14-11 3.q 2.A 1.0 16 n 3.3 71 .10 *70 80 c,F r' ni-;50 ?. 7. c; lop is 6.1 79 ell *50 50 orT ?n-11) -3 6.3 1.0 20 6. c; 91 *12 *so 60 0 -1 -:) 7 3./- 6.n 7.1 18 86 .12 *60 so UNITTI.f) STATFS DFPwT14F@J Ir, JHTFPTOP - rFOLOGICAL SUPVi-Y P@;,OCFSS DATE 09/29/ki f-1P7n614qj0@,()()n - F'@LIJMA C rL FKLUT@IA nlVFH,;Trm :)o%M NR PALMFR AK r)TSTPTCT CODE 02 W@TFR QUA[_TTY ()ATA SPF_ NITRO- CIFTC CARMN GEN, rnj,.OP com- nTox1nF ALKA- PTCAP- NITRATE HARD- (PI-AT- I)lJrT- DIS- UNITY BONATE CAR- uls- NESS I sJ1.1m ANCE PH SOLVFr) (MG/L (MG/L 80NATF SOLVED (MG/L COPALT (MICRO- FIELD (MG/L AS AS (MG/L (MG/L AS nfJF 01"TTS) MHOS) (UNITS) AS COP) CAC03) HC03) AS C03) AS N? CACOV (rinngn) (nnngS) (On4OO) (oo4oq) (nn4jn) (00440) (00445) (00618) (0090o) ')F(7 4 1,090 01_1c@ 5 14A 7.8 1.6 52 64 0 .14 64 VAP 9 30o.* j!;A 62 7c; 0 018 73 APP n2-30 5 157 7.6 3.1 62 76 0 *20 70 MAY 04-P51 C5 i4A 7.A 1.7 9 7 69 0 o16 68 JUN () I - I r, 5 142 7.5 3.3 94 A6 914 69 J@ IL 02-11 S 129 7.3 4.7 48 5A 0 .14 64 16-1() 5 116 7.3 4.1 43 53 0 oil 57 a U G ()3_11 C; 113 7.2 5.? 43 52 0 .16 57 17-11 9 112 7.4 3.? 42 51 n .16 55 SF@p ol-)4 5 120 7.4 3.6 46 S6 0 *14 56 17-2P 5 120 7.5 ?.A 45 55 ell 61 OCT 5 l3n 7.5 3.? 52 A3 0 Oil 67 9 136 7,4 4.1 52 A4 0 -11 67 02-1? C; 138 7.6 2.7 55 67 0 014 70 1 A - -.1 m C; 1,36 7.6 2) . 0; 53 65 0 ell 65 nFC 03-?" 5 )33 7*1 8.Q t; 7 7 n .14 66 aq? 0 136 7.1 8.1 92 64 n .14 69 1 0 13c; 7.1 8.1 9 3 69 1) 14 72 0 A P 03-31 5 134 7.2 6.7 9 a14 66 54 60; 0 APQ n4-?-" 9 14ck 7.3 9. 0 An 73 0 *09 78 y 197 7.5 4.2 68 Pi 0 ell 80 U'JlTF") STATFS DEPA141'ArNIT OF PITERIOR - rFOLOGICAL SURVLY PPOQFSS UATE 09/29/gi 4@1?7nic,1491nqmOP - Ft@LUTW C rL F-LUTIJA OTVERcTof,j nAH NR PALMER AK DISTRICT CODE 02 WATFR Q11ALITY DATA SODIUM+ MA(;NF- ,Onjum POTAS- POTAS- CHLO- CALCIUM STUM9 SODIUM, AD- sitim S IUM 9 RIDE9 NOIIJCAQ- D TS- D T S_ D I S_ @Opp_ DTS- DIS- DIS- 9()@JATF SOLVF0 SOLVED SOLVEM TIO1ql SOLVEn SOLVED SOLVED 04r/L (MC,/L (MG/L (fAC111_ PATIO SODIUM (MG/L (MG/L (MG/L r) A TF CArO3) AS CA) AS MG) AS NA PERCENT AS NA? AS K) AS CL) (nn,o()2) (nogis) (nn925) (no93n) (on931) (On937) (00933) (00935) (00940) r)EC q I C)9n 01-11; 11 20 3.5 4,9 1.5 14AP v 1051 3n... 290 @Pp 02-10 A 21 4.3 4*0 18 "A Y 04-2A 21 3.8 2*0 JUN 1)I_Ir_ is 21 4*0 3.o 2.5 J1 IL n?-Il 16 20 3.5 3.0 4,2 16-3n 14 is 3.0 2*5 2.8 AIJG @3-11 14 18 2.9 4.3 5.8 17-31 13 17 3.0 3*4 208 SFP 03-14 10 16 3.() 7o9 7*0 17-28 16 19 3.4 393 5*2 OCT 01-ir- 15 2f) 4.1 5.1 4.8 lc)-2f) 14 7n 4.1 So 4.8 Nov f)2-1 ? I C; 22 3.7 3.7 590 16-in 12 21 3.1 5e2 4.2 nFr, 0 3-2'1 9 20 3.9 6.9 J04 9 1')5p n7-;)4 16 21 4.1 2.9 7.5 n I -?r) 39 22 4.1 1.5 2.5 A P ,)I ? n 3*q 1 -11 12 500 2*2 @pp 04-?m 18 ? 4 4..l 6 .7 102 A Y 1 1-2 1 9.6 P.7 .1 7 .7 1.0 UKITTFn STATES 1EP@RTtirj,IT OF INITFRIOP - CVOLOGICAL sUPVEY PRICESS DATE 09/29/81 6127A6149115000 - FKLUTNA C PL F,<L(,ITKIA DTV@JISTON OAM NR PALMER AK DISIRICT CODE 02 WATFR QIIALITY DATA qnLIOS9 SOLIDS, NITRO- FLUO- STLICA# PFSIDi_,iE Sum OF SOLInSt GEN@ SULFATF PII)E, DI'3- AT 19n CONSTI- DTS_ NITRATE 01s_ nIS_ SOLVED DEG. C TUENTS* SOLVEn Ols- SOLVFD SOLVED (MG/L DIS- DIS_ (TONS SOLVED IRON (Mr,/L (MG/L AS SOLVED SOLVED PER (MG/L (UG/L r)PTF AS 5041 Aq F) SIO?? (MrYIL) tMG/L) AC-FT) AS N03) AS FE) (00945) (00950) (00995) (7o3oo) (7(i3ol) (703n3) (71851) (71885) !,F r . 195() ml-I-, 19 4.6 86 .12 60 40 1951 7.0 080 @Pp A?-3n 14 5.4 8A .12 190 10 AY n4-?n 14 4.3 80 .11 70 30 J, IN, 0 1 - I C; 105 02 7*5 87 .12 .60 40 it 11- n;,-13 16 .1 4.6 91 .11 60 10 16-3n 14 *1 4.7 72 .10 .50 30 Ator r) 1 - 11 14 .1 3.7 75 010 .70 30 17-31, is *1 4.0 71 .10 .70 7o qr,p ()1-14 16 61 3.6 83 .11 .60 17-PR is *1 3.8 77 .10 150 40 orT n I - I c; is 5*3 89 .12 .50 110 C)-?C) 17 4.2 87 .12 .50 50 "3-1;? 15 4#1 87 .12 o6o 60 16-3.n 16 *1 109 84 Ill .50 90 r'F,r Is 94 *13 60 j A V@ 9 195'? 11 T_pck IR 5.6 A3 86 *11 .60 3n FFn nl-?Q 17 60 6.1 A4 86 60 3o G 1-31 11 4.4 A -1 87 111 60 60 17 6.1.1 92 .12 .40 40 y 17 P. f qq 100 .13 159 20 k UNITF0 STATFS DFPAWT,IF@IT )F INTERIOR - rr:OLOGICAL SURVEY PROCESS DAIE 09/29/81 6j2A-36141)0R4A0o - EKLIJTNA Q NL PLANIT NP FKLIJTNA AK DISTRICT CODE 02 WATER QoALITY DATA F,PE- CIFIC CARBON STPFAM- COLOR CON- DIOXIDE ALKA- BICAR- TrK!PFP- FLOW, TUR- (PLAT- r)IJCT- oxYGENv ols- LINITY @3ONATE CAR- IMIRE, INSTAN- RID- I tq t.1 14 4NCE DIS- PH SOLVED (MG/L 04G/L SONATE TPIF .'-JATER TANcOljS TTY COBALT (MICRO- SOLVED FIELD (MG/L AS AS (MG/L nATr Mrs C) (CFS) (JTU) UNITS) MHOS) (MG/L) 0JNITS) AS C02) CAC03) HC03) AS COJ) (00()10) (non6l) (W70) (OOOR()) (n0095) (0000) (no4(jo) (nn405) (00410) (00440) (00445) nr.T 9-?2 nA ... 14?n 6.c; 371 25 0 1?6 10.9 7.9 101 44 54 0 nFr lp ... 0on 2,r, 438 9 6 141 7.8 1.6 51 62 0 FFn , 197-t 01 ... inin eq 10 3 144 7,7 2.0 51 62 0 19 ... 1400 3.n 236 4 143 APP 17 ... Ir,20 3.n 193 7 5 143 7.5 3.3 54 66 0 J1 11- 17.o. 1149, 11eq 145 21 30 144 909 -%7 2*2 57 69 0 11 ... i. n 113 1 P. C; I r. 9 40 in 1,38 10.6 801 .9 55 67 0 /Mr 11 ... 1500 lo.n 27n 20 Ils 7.8 1.5 48 59 0 27 ... 1111i lo.q 275 39 9 131 11.0 800 190 52 63 0 SFP ... 1100 9.0 331 is Ipo In.4 45 55 WITTFf) STATFS or I-NTFPI()4 - ';VOLOGICAL SURVEY PW0CFSS DATE 09/29/Al Al?11614qnR4An0 - FKLIJT'JA Q RL POJFP PLPIT fJP FKLIITNA AK DisrRicT CODE 02 -ijAT;.P QiiALITY OATA 14 1 Tp0_ ''TTPO- plios- P140s_ @j 11-Nv PHORIJ-,, PHORUS9 HARD- PAAGNE- SODIUM POTAS- t@TTPATF Nn2@NOI 0QT40PH ORTHOPH HARD- KIESS, CALCIUM SIOM9 SODIUMI AD- STU149 T I;- " T's- CISPHATE OSPHATF N F S S NONCAQ- DIS- M S_ DIS- SORP- OTS- cr)t VFr) r) I S@OL. D I SSOL. (MG/L RONATF SOLVED rIOLVED SOLVED TION SOLVED (1.4r./L p,r/(_ (MG/L (m(3/L AS (MG/L (MG/L (mr,/L (MG/L RATIO SODIUM (MG/L r)ATF Aq ") Ar, N) AS P04) AS P) CACOI) CAC01) AS CA) AS MG) AS NA) PERCENT AS K) (0"Ip) (IOA31) (00660) (nn671) (no9no) (no9n2) (00915) (no925) (no930) (00931) (00932) (00935) f-,rT . 197? 06 ... .11 97 13 iq 247 2.5 *1 9 *2 rF-r I's ... .04 *n3 -Oln 62 11 2o 3.0 3-0 *2 9 .15 Frn . 1973 n1 ... #07 no <.Olo 6c; 14 21 3*1 2eB e2 8 *4 APP 17 ... .13 *00 <.Oln 6r, 11 21 3.1 2.7 *1 a 4 VIL 17 ... '1p no <.Oln 66 9 21 3.2 2.8 e2 8 5 31... 413 nn <-010 74 19 25 2.8 2-9 *1 a 94 AUG 11 .11 .00 <0010 99 11 19 2.9 3.3 2 11 6 77 ... *I? *n3 .0in 99 7 19 2.7 2.6 .1 9 03 CFP 14 *00 <001n 99 14 19 2.8 2-5 61 8 7 UMITr'D STATFS DEPAPPIFmT OF INTFRIOR - rFOLOGICAL sURVEY PROUSS OATE 09/29/81 612AlA14q0q4900 - EKL(]T',IA R RL (3f)UFQ PLA14T 'JP FKLIITf4A AK DISTRICT CODE 02 WATER ()iihLlTy DATA (71 IL n FLIJO- SILICA9 CHRO- 4int. q1.11- CATF R InE D I S_ ARSEN I r UPIUM9 CAnmli.)m M ILIM 9 COPPER9 IRON9 LEADt ()IS- r) T I S- SOLVED DTS- nts- DIS- DIS- DIS_ DIS- DIS- Snj_ vFi) S')j_VF7D SOLVFD (MG/L SOLVFn SOLVED SOLVFr) SOLVED SOLVED SOLVED SOLVED ("111- CA r / 1'. (MG/L A S (UG/L MG/L ((JG/L ((J6/L (UG/L (UG/L (UG/L r)P.Tr AS rL) AS q04) A; F) ST02) AS AS) AS RA) AS CM AS CR) AS CU) AS FE) AS PB) (nn940) (Olq49) (ongso) (00955) (0100n) (nl()f)c;) (01n;-)Cz) (olo3o) (01040) (01046) (01049) ')CT 1972 16... 1.1) 13 <.I 6.3 110 nrc 4.;) 19 80 FPP IQ73 2.8 20 APP 17..* 1.3 17 <.I 2.8 so J1 Ip 7... 18 2.R so 11 ... P.7 19 2.7 1 Q 17 <.I 2.9 <1 <100 NO 11 <10 <2 1.5 is *1 2.6 80 c@; r p 3.4 16 1.0 3 o A 50 11NITF71 SIATFS ')r TNTFRIOP - rFOLOGICAL SUHVFY PPOCESS UAIE 09/29/81 f,jPRlA1490q4q00 - F-KLIJT@IA R AL P010P PLAW NP FKLUTNA AK DISTRICT CODE 92 WATER QIJALITY nATA COLI- SOL I DS . NITRO- SEI) I - k, SELE- FORM, slj@ OF SOLMS, SOLIDS9 GEN9 MENT %IF(;@. ',TLVFP, ZTNCq NIt.jmq TOTAL. CONSTI- DIS- ols- NITRATE SEDI- uls- r) 1 4@,- r) I - - MEWT9 CHARGE9 DIS- r) 1 s- immEn. TijENTS. SOLVFn SOLVED Dis Sol_ vg@ 11 rnl-vFn SOLVFD SOLVED (COLS, r) 15- (TON11r, (TONS SOLVED SUS- SUS- Wr /I- (11r/L Mr,/L MG/L PFP e0LVFr) PER PER (MG/L PENDED PENDED N03) (MG/L) (T/DAY) n,,Tr AS W-1) AS Ar,) AS ZN) AS SE) ion ML) (MG/L) nAY) AC-FT) AS (010511;) (oln75) (ningo) (01145) (11501) (70301) (7nin;)) (70303) (71851) (80154) (80155) (le'T 107?, rll'@ ?@ -- -- -- Rn 71 71.1 .10 050 17 17 ncr in ... <In A3 9q.;) .11 -- 10 12 FFR , jq7-1 <1(1 92 2.21 .11 -- -- -- 4 2*5 APr 17-6 81 4297 .11 3 1*6 ji111 7, R14 A4 32.9 *11 20 7*8 ii ... 817 88 37*A 012 13 5*6 <In NO) 50 <1 sn 76 45.1 .10 -- 27 ?n -- -- -- Ap 79 S8.7 .11 a *. 2 c;Fr 5 4-5 2t, ... 12n 77 68.8 .10 NOAA COASTAL SERVICES CTR LIBRARY 1@ I 3 6668 14110066 1 1