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HomeMy WebLinkAboutItem 4.08 Water Recycling Study CITY OF DUBLIN AGENDA STATEMENT City Council Meeting Date: March 23, 1992 SUBJECT: Livermore-Amador Valley Water Recycling Study Report by: Public Works Director Lee Thompson EXHIBITS ATTACHED: Summary Report Study Results RECOMMENDATION: UYx Receive report. FINANCIAL STATEMENT: None at this time. The proposal would eventually increase the cost of water delivery to the Tri-Valley area. DESCRIPTION: In an effort to develop new sources of water in the Tri-Valley area, as well as to reduce the need to export treated effluent, the Zone 7 Water Agency, the Dublin San Ramon Services District, and the City of Livermore funded a study regarding the re-use of treated water in the Valley. The summary report by Brown and Caldwell outlines the results of that study. Out of eleven original proposed projects, seven were selected for detailed development and evaluation. Of those seven projects, the report recommends that the following three projects proceed as a preliminary recycling program. 1. Project W-1: Use of nondemineralized recycled water for landscape irrigation in the Valley area, primarily from North Pleasanton northward to the Dougherty and San Ramon Valleys. The unused winter recycled water would-be used to recharge the ground water through injection wells. 2. Project W-4: Recharge of the Central Groundwater Basin with demineralized recycled water through a chain of lakes (rock quarry pits south of the E1 Charro/I-580 interchange) . 3. Project E-6: Groundwater recharge with demineralized recycled water through streams and the basin. The current estimated re-use from the three projects above is 10,600 acre/feet per year with a potential future volume of 25,500 acre/feet per year. The projected cost of producing this recycled water at today's costs is in the $1,000- to $1,200- per-acre/foot range. The present Dublin San Ramon Services District delivered price of potable water is $550 per acre/foot. Implementation of these projects would require a permit from the Regional Water Quality Control Board, would require development of a salt management program, and would require an agreement between these agencies to establish cost sharing and policies and responsibilities for the work to be done. This study identifies initial feasible recycling projects and outlines a work plan to proceed with implementation. It is up to the three agencies to pursue the additional steps for the realization of these projects. a: (corres)\mar\agsth2o ----------- ----------------------------------------------------------------------- ITEM NO. COPIES TO: CITY:1/ C L E R K FILE . �. --.--....._._._WATER RECYCLING STUDY SUMMARY REPORT STUDY RESULTS Alameda County Flood Control and Water Conservation District, Zone 7 Dublin San Ramon Services District City of Livermore Prepared by: BROWN AND CALDWELL CONSULTANTS DAVID KEITH TODD CONSULTING ENGINEERS, INC. EOA, INC. March 5, 1992 WATER RECYCLING STUDY SUMMARY REPORT STUDY RESULTS This summary report presents the results of the Livermore-Amador Valley Water Recycling Study undertaken by the Zone 7 Water Agency, the Dublin San Ramon Services District, and the City of Livermore. This report is an update of the November 21, 1991 summary report. It contains previously presented information on project development and evaluation and on program recommendations. The report also contains additional information on project permitting requirements and institutional arrangements. BACKGROUND The principal objective of the Livermore-Amador Valley Water Recycling Study has been to investigate the feasibility of water recycling in the Valley while continuing to protect and enhance the water resources in the Central Groundwater Basin. The study focused on both indirect potable reuse through groundwater recharge and on direct nonpotable reuse of recycled water transported by pipeline from water reclamation facilities to specific reuse sites. The major tasks of the study have been as follows: • Review of Previous Work. A wealth of information is available from previous investigations undertaken in the Valley over the last 20 years. The purpose of this task was to review that work and to document it in a concise manner. • Water Supply, Groundwater, and Recycled Water. The purpose of this task was to identify potential groundwater recharge methods and areas and to determine the eArepons\6054-01.wxs(030492) 2 potential interrelationships between water supply and groundwater recharge of recycled water. • Recycled Water Market Assessment. For direct reuse of recycled water, potential reuse categories and sites were identified. Landscape irrigation is the largest potential reuse category in the Valley. • Evaluation of Alternatives. Specific water recycling alternatives were developed and evaluated. Key projects, which are expected to receive the focus of future attention for construction, were identified. • Permitting Requirements and Institutional/Policy Considerations. The probable provisions of recycling project permits were identified, and the steps involved in obtaining a permit were outlined. In addition, potential institutional arrangements among project participants were identified, and other policy needs were discussed. IDENTIFIED PROJECTS The term "project" is used in this study to mean specific water recycling elements that will use a given amount of water in a certain way. For example, one project envisions using 4,000 acre-feet per year (acre-ft/yr) of demineralized recycled water to recharge the Central Groundwater Basin by putting the water into the Chain of Lakes. There are two important characteristics of project as defined in this report that should be understood. 1. Minor or even moderate changes within each project can be made without requiring a new project to be identified. Thus, in the example just noted, the eArepmU\60_U-01.VM(03049Z 3 amount of water recycled, 4,000 acre-ft/yr, may be increased above the amount shown if, for example, the overall use of water from the basin is increased. The purpose of this characteristic, permitting change within projects, is to minimize the number of projects that need to be evaluated. 2. Some of the projects identified in this memorandum will be mutually exclusive, i.e., they cannot all be implemented. In particular, the projects that provide for recharge to the Central Groundwater Basin could all provide approximately the same amount of water for the same use: extraction at existing municipal supply wells. Other projects are additive, however. Some provide recharge for domestic use; others recycle water for landscape irrigation. To the extent that there is enough recycled water available, several projects can be added together to form a larger project. Two main reuse categories account for essentially all of the recycled water volume identified in the study. The first is landscape irrigation through direct reuse. The second is groundwater recharge for municipal use, including potable use. Water recharge to the Central Groundwater Basin would be extracted through existing and future supply wells and used in the existing Valley municipal water system. Eleven separate projects were identified. Five of these are located in the western portion of the Valley and would use the Dublin San Ramon Services District wastewater treatment plant as the source of recycled water. These projects are identified as W-1 through W-5. The other six projects would use the Livermore Water Reclamation Plant as the source of recycled water; they are identified as Projects E-1 through E-6. Project W-1, Use of nondemineralized recycled water for landscape irrigation in the San Ramon Valley and Dublin area. «\repcnuk6054-0t.wxs(030492) 4 Project W-2, Use of demineralized recycled water for well injection recharge to the Central Groundwater Basin. Project W-3, Use of demineralized recycled water for landscape irrigation in the Pleasanton area. Project W-4, Use of demineralized recycled water for groundwater recharge to the Chain of Lakes. Project W-5, Use of demineralized or nondemineralized water for landscape irrigation in the Sunol area. Project E-1, Use of nondemineralized recycled water for landscape irrigation in the North Livermore area. Project E-2, Use of demineralized recycled water for injection well recharge to the Central Groundwater Basin. Project E-3, Use of demineralized recycled water for stream recharge, landscape irrigation, stream enhancement, and agricultural irrigation in the southeast Livermore area. Project E-4, Use of demineralized recycled water for stream recharge, landscape irrigation, and agricultural irrigation in the south Livermore area. Project E-5, Use of demineralized recycled water for stream recharge and Chain of Lakes recharge in the area near the Livermore Water Reclamation Plant. o:VcpwU\605"1.WM(03049 5 Project E-6, Use of demineralized recycled water for stream recharge and spreading basis recharge in the Livermore area. SELECTED PROJECTS Based on a screening process, the following seven projects were selected for detailed development and evaluation: Project W-1, Use of nondemineralized recycled water for landscape irrigation in the San Ramon and Dougherty Valleys, Dublin, and the Stoneridge and Hacienda Business Park areas of north Pleasanton. Portions of this alternative have been studied in detail by both Dublin San Ramon Services District and the East Bay Municipal Utility District, and strong interest has been expressed in implementing this project. Project W-1 could also be linked with existing Livermore recycling facilities and with Project E-1. During the winter when irrigation demand is low or nonexistent, water would be stored in an aquifer. Project W-3, Use of demineralized recycled water for landscape irrigation in the Pleasanton area. This area is in the Zone 7 water service area and over the Central Groundwater Basin. Thus, demineralization of irrigation water is desired to reduce the salt loadings to the Central Basin. Put-and- take groundwater aquifer storage is used for winter recycled water flows. Project W-4, Recharge of the Central Groundwater Basin with demineralized recycled water via the Chain of Lakes. Recycled water would be transported from the Dublin San Ramon Services District wastewater treatment plant to the e:VcporU\605"1.WRS(030492 6 western recharge face of the Chain of Lakes. Full implementation of this project would need to await completion of mining operations in the area, but initial recharge efforts could probably begin sometime between 2000 and 2005 when operations in the western portion of the area have been completed. Project E-1, Use of nondemineralized recycled water for landscape irrigation in the north Livermore area. Because this area is currently undeveloped, it provides an important opportunity for maximizing use of recycled water through dual water systems. Recycled water could be used for or most all irrigation facilities plus nonpotable uses in commercial and industrial facilities. Project E-1 could be connected with existing Livermore water recycling facilities and with Project W-1, providing for an extensive irrigation system north of Interstate 680. A surface reservoir would be needed for winter storage as there is no suitable location for groundwater put-and-take storage*. Project E-3, Use of demineralized water for landscape irrigation in Livermore, agricultural (vineyard) irrigation in the southeast Livermore area, and stream recharge, basin recharge, and Chain of Lakes recharge to the Central Groundwater Basin. This project provides a wide range of uses for recycled water. Recharge basins would include the abandoned Livermore Oxidation Ponds and a city-owned parcel in the Madeiros Parkway. Recycled water would be delivered to the Madeiros Parkway Basin from an upstream discharge into Arroyo Mocho and then pumped out of the Arroyo into the basin. For the irrigation component, winter recycled water flows would be stored in a put-and-take aquifer storage system. e:\reports%605"1.WM(0304M Project E-4, Use of demineralized water for stream recharge, basin recharge, and Chain of Lakes recharge to the Central Groundwater Basin and for landscape and agricultural irrigation in the south Livermore area, particularly in the proposed Ruby Hill development. This alternative could be staged to provide groundwater recharge initially and irrigation in the future when the Ruby Hill development is begun. As with.Project E-1, dual water systems could be included in the new development to maximize recycled water use. Groundwater storage would be used for winter-time recycled water flows. Project E-6, ' Use of demineralized recycled water for groundwater recharge through — stream recharge and basin recharge. The advantages of this project are that with no irrigation component, there are no large winter storage requirements, and that a relatively low-pressure pumping and piping system is needed to deliver the recycled water to the turnout points for stream addition. The projects that were eliminated from consideration are W-2, W-5, E-2, and E-5. These are discussed below. There are hydrogeologic uncertainties associated with Projects W-2 and E-2. First, the potential for forming a "barrier" to prevent migration of salty groundwater from the fringe basins to the Central Basin is incompatible with the need to inject the recycled water at a deep level to maximize the potential for travel to the extraction wells. Further, even at the deeper layers, there may be poor continuity between the injection wells and the existing extraction wells. Recharge to the Central Basin can be accomplished less expensively through some of the other projects under consideration. alrepotu\6054 INN(030492)) 8 Project W-5, landscape irrigation in the Sunol area, was eliminated because it is outside of the Zone 7 water service area and, unlike the area covered by Project W-1, has received little previous attention. It does hold promise for the future, however. A joint study by Zone 7 and the San Francisco Water Department may be appropriate. Project E-5 is merely a truncated version of Project E-6 and could be developed as a first stage of that project. Therefore, it does not warrant evaluation as a separate alternative. DEVELOPMENT OF PROJECTS The seven projects identified in the screening process were developed further for more detailed evaluation. Three important topics relating to project development are (1) target reuse capacity, (2) available wastewater flow, and (3) degree of demineralization. Target Reuse Capacity Based on Zone 7's recent evaluation of future water supply needs plus a desire to increase the reliability of supply as well as recognition of the potential for reverse osmosis to play an important role in salt management in the Central Basin, a target reuse capacity of 10,000 to 20,000 acre-ft/yr has been identified. This is not a firm goal but provides a general objective with regard to water supply needs. Available Wastewater Flow The recommended plan should provide a reasonable overall balance between recycled water demand and available wastewater flow. There are currently continuing debates within the Valley on the appropriate growth scenarios. These debates make future flow projections e:VepoM\601"1.WM(030492) 9 particularly difficult. For the purposes of this study, the following values have been chosen for current and future flows. The range in future flows cover the range in growth projections from a "constrained general plans" scenario to a "prospective general plans" scenario as identified in the subsequent environmental impact report (SEIR) for the Tri-Valley Wastewater Authority (TWA) Wastewater Export Project. These flows are shown below: Current Future DSRSD 8.0 mgd 20-27 mgd (9,000 acre-ft/yr) (22,000-30,000 acre-ft/yr) Livermore 5.0 mgd 10-18 mgd (5,600 acre-ft/yr) (11,000-20,000 acre-ft/yr) Total 13.0 mgd 30-45 mgd (14,600 acre-ft/yr) (33,000-50,000 acre-ft/yr) Degree of Demineralization For the purposes of project evaluation, the identified degree of demineralization, i.e., the specific recycled water salinity level, has been based on current Zone 7 and Regional Water Quality Control Board policy and on proposed Department of Health Services regulations for groundwater recharge projects. The following total dissolved solids ('IDS) concentrations were used for project development and evaluation: • Irrigation, fringe subbasins, 700 mg/L (current wastewater effluent value, no demineralization). • Irrigation, Central Basin, 250 mg/L (current limit identified by Zone 7 and Regional Board policy). e:ltgmU\W5"1.WR.4(030492) 10 0 Recharge, surface spreading, 170 mg/L (based on proposed regulations for organics removal for groundwater recharge by surface spreading. 0 Recharge, direct injection, 100 mg/L (based on proposed regulations for organics removal. It is important to note, that with regard to the Zone 7 and Regional Board policies on total dissolved solids in Central Basin surface and groundwaters, the use of reverse osmosis provides a powerful tool to develop a new approach to salt management in the basin. Therefore, the salinity concentrations used in project development in this study may be modified as project development proceeds and as new policies are developed that provide for a more comprehensive basin management approach than has previously been possible. PROJECT DESCRIPTIONS AND COSTS A summary of the recycled water use associated with each project is shown in Table 1. The layouts for the distribution pipelines for each project are shown on Figures 1 through 7. Recycling volumes associated with "current" conditions are based on (1) serving existing direct reuse sites and (2) restrictions on groundwater recharge associated with ongoing quarry operations. Volumes associated with "future" conditions include provision of recycled water for residential landscape irrigation of new developments using dual water systems. In addition, once quarry operations are complete in the Valley, additional groundwater recharge volumes will be possible. A summary of the capital and operation and maintenance cost estimates for the projects are presented in Table 2. Costs are based on 1992 price levels (Engineering News-Record Construction Cost Index of 6300 for capital costs). Total annual costs are based on an e:VvpmU\605"1.WM(03044 11 annualized capital cost computed at 8 percent interest over 20 years. Also shown in Table 2 are the annual use in acre-ft/yr and the unit cost in dollars/acre-ft. The unit cost breakdown between treatment and distribution is shown in Table 3. The unit costs generally fall into two categories: those near $1,000 per acre-ft (W-1, W- 4, E-3, E-4, and E-6) and those in the range of$1,500 per acre-ft (W-3 and E-1). Based on the cost analysis and the initial elements of the noncost evaluation, projects W- 1, W-4, and E-6 warrant the most attention. These projects, or modifications of them, are part of the recommended water recycling program resulting from this study. The final program recommendations go beyond identifying projects for implementation. The recommendations also discuss how other current and proposed recycling projects can fit into the overall program. For example, additional recycling projects in the vicinity of both of the wastewater treatment plants in the Valley may be appropriate. In addition, the recommendations. discuss possible policy changes with regard to demineralization and restrictions on TDS levels' used for various purposes in the Valley. Finally, the recommended program includes a description of data and information needed to effectively manage the Central Groundwater Basin in an era when the use of reverse osmosis demineralization will permit a much more effective approach than has been possible. PROGRAM RECOMMENDATIONS Based on the cost estimates presented in the previous section plus preliminary work on the noncost analyses, the following preliminary program recommendations have been developed. These recommendations are based on development of a Long-Term Water Recycling Program in the Tri-Valley area rather than being restricted to near-term construction of one or more cArepocts\6054-01.wRS(0304912) 12 alternatives. A specific set of projects is identified as the focus of the program, but additional project elements from other identified and evaluated projects can be included. In addition, the framework is developed for constriction of other project elements that may not be specifically identified and analyzed in this study. Key Projects It is recommended that the recycling program focus on Projects W-1, W-4, and E-6. These projects provide for a variety of reuse categories in the West Valley and East Valley areas. The current potential reuse volume associated with these projects is 10,600 acre-ftlyr, and the future potential volume is 25,500 acre-ft/yr. Costs for the key projects are summarized in Table 4. As noted above, additional project elements can also be included in the overall recycling program. Such elements might include (1) landscape irrigation in the Pleasanton area near the DSRSD wastewater treatment plant (elements of Project W-3), (2) landscape irrigation of the Springtown Golf Course (an element of Project E-1), (3) and irrigation of the vineyards in the area southeast of Livermore (part of Project E-3). Project elements that are not evaluated in detail in this study include injection well recharge near the DSRSD plant. Alternative W-2, which envisioned combining well injection with a saline water intrusion barrier adjacent to the fringe groundwater basins was rejected in the screening stage because of technical uncertainties and the ability to accomplish the same recycling goal (groundwater recharge) through other means at less cost. A separate injection well program could be developed, however, focusing on recharge only rather than combined recharge plus salinity intrusion prevention. Such a project would have the advantage that it could be implemented before the Chain of Lakes becomes available in 10 to 15 years. e:krepmUk6O5"1.WM(0304M 13 These examples show how the Recycling Program can be a flexible scenario that can accommodate changing conditions in the Valley, rather than a fixed, inflexible set of alternatives that may become obsolete as technical, regulatory, and political changes occur. Policy Changes The alternatives developed and evaluated in this Summary Report are based on current Zone 7 and Regional Board policy regarding salinity and on proposed Department of Health Services regulations governing groundwater recharge and direct reuse. It is important to understand that, especially with regard to the policies on salinity and recycling, reverse osmosis provides a powerful new tool for ensuring that water recycling can be accomplished without adversely affecting beneficial uses. It may be appropriate to develop new policies on TDS concentrations in recycled water in the Valley. Cost, water quality impacts, and regulatory requirements will all need to be taken into account as this question is explored. Increased Groundwater Use Currently, groundwater is used principally as a backup source of supply in the Valley, with treated (imported and local) surface water providing the great majority of domestic supply. The maximum amount of recharged recycled water plus required dilution water identified in this study (and included in the set of key projects identified above) is 33,000 acre-ft/yr. An equal amount will need to be extracted and used each year. This will require a significant shift in emphasis by Zone 7 and the Valley water retailers. The implications of this shift should be identified and understood by all the parties involved. Hydrogeologic Data Proper management of the Central Groundwater Basin under future conditions (with additional recharge and groundwater use) will require an improved understanding of the basin e:WcpoM\6054-01.WM(030442 14 characteristics. It is recommended that Zone 7 acquire the necessary hydrogeologic data and expand its existing monitoring system to permit evaluation of the impact of water recycling on groundwater levels and quality. This will, in turn, permit better management of groundwater quality and a more efficient approach to protection of beneficial uses of the basin. Salt Management Water recycling is neither a panacea for solving all of the salt issues associated with the Central Groundwater Basin, nor is it the cause of all the salt accumulation that is occurring. It is important to understand the role of recycling in the overall salt balance and to take steps to efficiently use recycling to protect the beneficial uses of the basin. An overall salt management program should focus not only on water recycling (and associated reverse osmosis treatment) but also on wellhead demineralization and on diversion or barriers to salty flows into the basin. Water recycling can be an important element of the program, but it is not the only element. PROJECT PERMITTING REQUIREMENTS Several discussions have been held with the Regional Water Quality Control Board staff to identify their concerns and to outline the steps necessary for acquisition of a permit for the reclamation program. These discussions have focused on several key issues, including the following: • Use of a "blanket" permit for the entire program, or acquisition of permits on a project-by-project basis. • Compliance with Basin Plan requirements, reuse regulations, and other regulatory constraints. o:Vepom\605 -ol.wxs(030492 15 "Blanket" Permits A desirable goal of the permitting process will be to obtain one "blanket" permit issued to the recycled water producers, distributors, and major users known at that time. One comprehensive permit will allow phased implementation of all potential uses identified as part of the overall program adopted by the responsible agencies. Such a permit would allow new projects to be implemented subject to executive officer approval rather than requiring new permits or permit amendments as each project in the program is brought on-line. Production of demineralized and nondemineralized water could be authorized under one permit for distribution to appropriate agencies and projects. The permit should be designed to allow maximum flexibility in determining which discharger supplies which users, particularly given the interrelated nature of the recharge projects. Permit requirements can be included for generic use categories and general use areas to accommodate future projects. The Regional Board staff has expressed support for the "blanket" permit concept, provided a salt management program is developed to ensure that all projects are undertaken in a manner that will ensure the long-term protection and enhancement of the groundwater basin water quality. Regulatory Compliance Key regulatory elements are (1) the San Francisco Bay Basin_ Plan and associated Zone 7 policies, and (2) the proposed Title 22 requirements for direct reuse and for groundwater recharge. Basin Plan. Current Zone 7 policies and guidelines and policies regarding water recycling are contained primarily in its 1982 Wastewater Management Plan in the context of e:Veporu\60_44-01.WRS(03044 16 regulating disposal practices for community wastewater treatment systems. These policies are also incorporated verbatim into the Basin Plan, where the Regional Board uses them as guidance in developing waste discharge requirements for the Valley. The Basin Plan includes three basic components: identification of waters of the state and associated beneficial uses (potential and existing), water quality objectives necessary to protect those uses, and a time schedule for achieving the water quality objectives. Key groundwater quality objectives are identified for total dissolved solids (TDS) and nitrate; key surface water quality objectives are set for TDS and chloride. It appears that a wide range of recycling projects can be implemented without modifying or amending the Basin Plan. This is probably contingent, however, on the development of the salt management program. The salt management program would be viewed as providing the framework within which local decisions could be made concerning the qualities, quantities, and locations of permitted recycled water use. Title 22. Water recycling regulations in California are developed by the State Department of Health Services and are contained in Title 22 of the California Administrative Code. Currently, specific regulations are being developed for groundwater recharge projects. (These projects were previously evaluated on a case-by-case basis.) In addition, the Title 22 regulations for direct reuse are being revised and refined. The recycling projects identified and evaluated in this study have all been developed to comply with the Title 22 regulations. These regulations are not in. final form, but review of drafts and direct discussion with the State Department of Health Services has provided a reasonable assurance that the projects will be able to comply with the final version. e:VepoiU\6054-01.WRS(030492) 17 INSTITUTIONAL ARRANGEMENTS The water recycling program in the Valley will require the participation of several entities. Zone 7 is the water wholesale supplier in the Valley as well as the agency with responsibility for protection of groundwater quality. Dublin San Ramon Services District and the City of Livermore have both water supply and wastewater disposal responsibilities. The City of Pleasanton and California Water Service Company are additional water purveyors in the Valley. Any large-scale water recycling project will likely involve two or more of these agencies. The institutional arrangements for carrying out reclamation projects among these agencies will be determined by the agencies themselves. Preliminary discussions among staff members have resulted in the following conclusions: • The three principal agencies--Zone 7, City of Livermore, and Dublin San Ramon Services District--will seek a Valley-wide "blanket" permit from the Regional Water Quality Control Board for implementing a Water Recycling Program in the Valley. Zone 7 will act as the "lead" agency with principal responsibility for obtaining the permit and enforcing its terms and conditions. • The three principal agencies will negotiate and execute a memorandum of understanding to develop the permit application. • The agencies will develop a salt management program to ensure that recycling projects are undertaken within a framework that provides for maintenance and enhancement of groundwater quality and protection of the Valley's groundwater resources. cArcpo u\605"1.WaS(030492 18 • Each agency will adopt a Resolution of Intent, which commits the agency to seek advancement of water recycling programs and projects. • Following acquisition of the permit, an agreement will be developed among the agencies to implement the Water Recycling Program. Key elements of this agreement will be cost-sharing arrangements, responsibility for ownership and operation of facilities, and implementation of the salt management program. • Each agency will need to develop policies with respect to its own interests in water recycling projects. For example, direct reuse projects will require policies to encourage or mandate reuse (e.g., use of dual water systems in new developments) as well as development of pricing structures for reclaimed water. The Livermore-Amador Valley Water Recycling Study has determined that water recycling--through groundwater recharge and direct reuse--is a viable method of supplementing limited water supplies in the Valley and that it can assist in meeting wastewater disposal needs as well. The steps for project implementation have now been identified. cAreporu\6054-OLVIRS(030492 Table 1 Summary of Reuse Quantities 19 Annual use, acre ft/yr Project Current Future West Valley Projects W-1 Irrigation 3,100 8,981 Recharge 01 0 Total 3,100 8,981 W-3 Irrigation 2,079 2,745 Recharge 0 0 Total 2,079 2,745 W-4 Irrigation 0 0 Recharge 0 4X0 Total 0 4,000 Subtotal, West Valley Projects 5,179 151726 East Valley Projects E-1 . Irrigation 180 1,980 Recharge 0 0 Total 180 1,980 E-3 Irrigation 6,094 6,094 Recharge 5,500 13,000 Total 11,594 19,094 E-4 Irrigation 414 L614 Recharge 6,500 13,500 Total 6,914 15,114 E-6 Irrigation 0 0 Recharge 7,500 12,500 Total 7,500 12,500 Subtotal, East Valley Projects 14,188' 26,188' Total, All Projects 19,367- 37,914" Excludes volumes duplicated by two or more projects. Table 2 : Cost Summary Current Future Total Total Capital O&M annual Unit Capital O&M annual Unit Annual cost, cost, cost, cost, Annual cost, cost, cost, cost use, thousand thousand thousand dollars/ use, thousand thousand thousand dollars/ Project acre-ft/yr dollars' dollars/yr' dollars/yrb acre-ft acre-ft/yr dollars• dollars/yr' dollars/yrb acre-ft W-1 3,100 29,100 860 3,820 1,230 8,981 76,600 2,380 10,180 1,140 W-3 2,079 23,200 1,290 3,650 1,760 2,745 27,200 1,590 4,360 1,590 W-4 - - - - - 4,000 22,900 2,410 4,740 1,180 E-1 - - - - - 1,980 25,700 480 3,100 1,560 E-3 11,594 71,400 5,870 13,140 1,130 19,094 94,000 9,530 19,100 1,000 E-4 6,914 35,600 3,570 7,190 1,040 15,114 63,800 7,080 13,580 900 E-6 7,500 37,100 3,770 7,550 1,010 12,500 51,700 5,780 11,040 880 '1992 Price Levels. bCapitai cost amortized at 8 percent over 20 years. N O Table 3 Unit Costs for Treatment and Distribution Current Future Unit cost, dollars/acre-ft Unit cost, dollars/acre-ft Annual Annual use, use, acre-ft/yr Project acre-ft/yr Treatment Distribution Total Treatment Distribution Total W-1 31-100 180 1,050 1,230 8,981 50 1,090 1,140 W-3 2,079 930 830 1,760 2,745 900 690 1,590 W-4 - - - - 4,000 1,100 80 1,180 E-1 - - - - 1,980 110 1,450 1,560 E-3 11,594 780 350 1,130 19,094 760 240 1,000 E-4 6,914 880 160 1,040 15,114 800 100 900 E-6 7,500 900 110 1,010 12,500 810 70 880 N 22 Table 4 Key Projects Current Future Annual use, Capital cost, Annual use, Capital cost, Project acre-ft/yr million dollars' acre-ft/yr million dollars' W-1 3,100 29,100 8,981 76,600 W-4 0 0 4,000 20,900 E-6 7,500 37,100 12,500 51,700 --FTotal 10,600 66,200 25,481 151,200 '1992 Price Levels. e:VreporU\605"1.WRS(030492) Alk 23 W-1 IoF 9.:: At DUBLIN-SAN ARAMON SERVICES DISTRICT WASTEWATER ... ........ TREATMENT PLANT ............ LEGEND CURRENT SITES 1000 FUTURE SITES 0 7000 SCALE IN FEET TURNOUTS FOR STREAM OR CHAIN-OF-LAKES RECHARGE POTENTIAL PUT-AND-TAKE GROUNDWATER STORAGE AQUIFERS FLOW EQUALIZATION TANK Figure 1 Project W-1 i 24 �+ "i DUBLIN-SAN RAMON SERVICES DISTRICT WASTEWATER W-3 _ .- • TREATMENT PLANT - - - .- -- _...,.. _,- - i 7000 ♦ _'�; SCALE IN FEET 4 'r _ - LEGEND �`J c,- FLOW EQUALIZATION f "A •;. /` �, TANK 1. ' a TURNOUTS FOR STREAM = - OR CHAIN-OF-LAKES ' RECHARGE J ..; POTENTIAL ,♦ 3 ,r ,rte�.. �y r PUT-AND-TAKE '_ = --___ _<:�.ti-,� �� . �� • GROUNDWATER ._ \ STORAGE AQUIFERS '•�, �' �'�:... "5 � ,a.�.: ;:y " Figure 2 Project W-3 f 25 tt I I J! I : 10 ............ 7e IN-O F-LAKES DUBLIN-SAN RAMON SERVICES DISTRICT WASTEWATER TREATMENT PLANT 1000 4 1 0 7000 SCALE IN FEET LEGEND TURNOUTS FOR STREAM OR CHAIN-OF-LAKES RECHARGE "Loo Figure 3 Project W- 00 ACRE-FEET 1 26 AVOIR 1. E-1 J, ........... ------- ...... ... ............ LIVERMORE WATER----7" RECLAMATION PLANT iY LEGEND FLOW EQUALIZATION TANK A. TURNOUTS FOR STREAM OR CHAIN-OF-LAKES RECHARGE J 1000 0 7000 SCALE IN FEET t4 4-z .� ff 0 Figure 4 Project E-1 27 vi OXIDATION POND BASIN' AIVERMORE WATER RECLAMATION PLANT M PARKWAY ADEIROS BASIN Qy, CHAIN-OF-LAKES ................ LEGEND ■ SURFACE SPREADING RECHARGE BASINS TURNOUTS FOR STREAM OR CHAIN-OF-LAKES RECHARGE POTENTIAL PUT-AND-TAKE GROUNDWATER STORAGE AQUIFERS mod 1000 5ham 0 7000 — - - r-, SCALE IN FEET Figure 5 Project E- 28 t. OXIDATION POND BASIN f rA .......... ....... LIVERMORE WATER !RECLAMATION PLANT \-ot n%-, reel ............ CHAIN- OF-LAKES E 4' oN­............ N "IN LEGEND m SURFACE SPREADING RECHARGE BASINS G TURNOUTS FOR STREAM OR CHAIN-OF-LAKES RECHARGE POTENTIAL PUT-AND-TAKE GROUNDWATER STORAGE AQUIFERS i000 0 7000 SCALE IN FEET file Y Figure 6 Project E-4 29 ..OXIDATION LIVERMORE WATER • RECLAMATION PLANT. 0 -POND BASIN L\. ... ........ .......... ....... MAI PARKWAY BASIN —......... CHAIN-OF-LAKES ............. LEGEND SURFACE SPREADING RECHARGE BASINS TURNOUTS FOR STREAM OR CHAIN-OF-LAKES RECHARGE V 1000 0 7000 SCALE IN FEET ti- Figure 7 Project E-6