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Table 5-2: Zone 7 Water Supply Sources Stab Water Project Sources Contract Maximum Amount (AFA) Contract TonnlExpilration Zone 7 SWP 1962 Contract (DWR Table A) 46,000 November 20, 2036 New SWP Transfers and Contract Amounts (DWR Table A) Berrenda Mesa SWP Transfer 7,000 November 20, 2036 Lost Hills SWP Transfer 15,000 November 21, 2036 Kem County SWP Transfer 10,000 November 22, 2036 Belridge SWP Transfer 2,219 November 23, 2036 Tulare Lake Basin Water Storage District SWP 400 November 24, 2036 Transfer Subtotal State Water Project 80,819 SWP Delivery Reliability Report 2002' 60,900 Other Surface Water Supply Sources Arroyo Del Valle Water Rights (Lake Del Valle? 9,300 Perpetual Renewal Byron Bethany Irrigation District 2,000 December 31,2028 Reclaimed Wastewater 1,900 In Perpetuity Groundwater Sources Main Basin Safe Yield 13,400 Zone 7 Sustainable Water Supply' 87,500 Calculated Annually Additional Groundwater' 15,000- 20,000 In Perpetuity Total Water Supply 100,500 105,500 Notes: a. Department of Water Resources Stele Water Project Reliability Report 2002 using CALSIM II model data predicted that average future SWP supplies would be 75% -76% of contracted amount Monterey Agreement DWRSIM model estimated 2020 yield at 75.57% of contract amount. Zone 7 staff agreed that 75.57% or 60,900 AFA average future yield is generally valid. b. Zone 7 Sustainable Water Supply Report, May 2007 uses 9,300 AFA for long -term water supply planning. Lake Del Vale estimated 12,000 AFA as Zone 7 reclaims local aggregate mining sites. c. Contract amount is up to 5,000 AFA, for conservative water resources planning purposes, Zone 7 uses 2,000 AFA. d 13,400 AFA is naturaly recharged to the Main Basin. Zone 7 estimates Main Basin Safe Yield at 13,400 AFA and splits this among Zone 7's retal customers (7,800 AFA) and other loaf pumpers make up the balance. GPO Groundwater Pumping Quota e. Zone 7 Sustainable Water Supply Report May 2007. Zone 7 includes irrigation demands met with reclaimed wastewater from Dublin -San Ramon Water District this WSA assumes that recycled water is always available and recycled water can be used to offset future increased irrigation demands but would not be available for potable uses. f. 15,000 20,000 AFA Average Annual Extraction based on historical pumping with no Net Lou to Groundwater Basin Zone 7 pumpage equals adifdal recharge quantity from surplus surface water. g: Total of all Zone 7 Water Supply Sources Source: 2005 Zone 7 Urban Water Management Plan, adapted by PBS&J/EIP September 2007. City of Pleasanton Final Water Supply Assessment Stoneridge Drive Specific Plan Amendment and Staples Ranch Project 4.0 Water Agency Background 5.3.4.3.2. Lake Del Valle Supplies Zone 7 holds water rights in the Arroyo Valle. Within the Arroyo Valle watershed, above Del Valle Dam, winter stormwater runoff is captured and stored in the Del Valle Reservoir also known as Lake Del Valle. Lake Del Valle provides Zone 7's service area with upstream flood protection in addition to local surface water storage. The reservoir is unique in that both winter storm runoff and late winter and spring SWP supplies combine to fill it to its seasonal operational capacity. In late fall, DWR typically lowers reservoir levels in anticipation of capturing winter storm run -off and to provide additional flood capacity prior to the rainy season. Del Valle Reservoir water is available through operating agreements between Zone 7 and DWR. The average annual thirty-year historic delivery to Zone 7 from Lake Del Valle has been about 8,000 AFA." The future reliability and long -term yield to 2025 is calculated at 9,300 acre feet based on modeling of historic runoff data and future changes in winter season demands. It is estimated, that as growth occurs and approaches buildout winter 16 2005 Zone 7 Water Agency, Urban Water Management Plan, page 21. P:wojns -VW onyw11e2°19YFle, Rosati INIIIM INFYW vra AN) 5 -14