View File - Development Services - City of Oxnard

7.0 Summary and ConclusionsThis section provides a summary and conclusions for the evaluation of the groundwaterelevation changes for the Phase 1 and Phase 2 scenarios of the GREAT Program. The generalelements the scenarios for each of these phases are similar and both consist of the following:• In-Lieu Groundwater Recharge using Recycled Water• Direct Injection Groundwater Recharge using Recycled Water• Groundwater Recovery for Potable UseHowever, the quantities of recycled water that were recharged to groundwater (eitherthrough in-lieu or direct injection) and equivalent quantities of groundwater recovered forpotable use are much smaller for the Phase 1 than for Phase 2. This is consistent with theobjectives of Phase 1 and Phase 2 for the GREAT Program, which are to:• Phase 1: Maximize the use of existing facilities to meet current water supply deficits• Phase 2: Expand Phase 1 facilities and build new Phase 2 facilities to meet the projectedwater supply needs of the City (based on planned growth) in 2020.As summarized below, the quantities of water recharged and recovered were approximately6.85 to 7.60 times higher for the Phase 2 scenarios than for Phase 1.Quantities of Recharged and Recovered WaterRecharge MechanismPhase 1(AFY)Phase 2(AFY)Phase 2/Phase 1In Lieu Recharge Only (1a, 1b – 2a, 2b) 2,814 19,286 6.85 xDirect Injection 534 6,172 —In Lieu Recharge + Direct Injection (1c – 2c, 2c2) 3,348 25,458 7.60 xThe changes in groundwater elevations in response to implementing the Phase 1 andPhase 2 scenarios, along with the impacts from those groundwater elevation changes, wereproportional to these quantities of water that were recharged and recovered.7.1 Phase 1 Scenarios7.1.1 Groundwater Recharge Using Recycled WaterIn addition to creating a new source of potable water supply for the City by maximizing theuse of current facilities, implementing the GREAT Program elements of the Phase 1scenarios will have the following benefits:• Scenarios 1a and 1b will result in small increases in groundwater elevations over broadareas across the southern Oxnard Plain and Pleasant Valley areas as a result ofdelivering recycled water to growers (Ocean View pipeline and PTP system) in lieu ofW112003002SCO LW1458.DOC/ 033390002 95