View File - Development Services - City of Oxnard

WATER RESOURCES TECHNICAL REPORTclimatically, using ratios of “wet” or “dry” pumpage, to average historical reportedpumpage for each subarea.Base Case Water Supply ProjectsThe following Base Case water supply projects in the existing management plan for theSanta Clara-Calleguas groundwater basin were simulated and analyzed to assess theireffectiveness at helping to manage the effects of increasing demand and variable supply onthe groundwater overdraft conditions.• Cessation of well pumping in the City of Oxnard from July 1995 throughDecember 1996, and a restart of pumping in January 1997.• UWCD surface-water deliveries of 900 AFY to Del Norte in lieu of pumping from theupper aquifer system starting in January 1997.• CMWD ASR project in East Las Posas Valley subarea from January 1997 toDecember 2001, using a proposed injection rate of 5,000 AFY for wet years; 1,250 AFYfor average years; and a pump-back recovery of 2,500 AFY for dry years. In 2002, theproposed injection rate was increased to 10,000 AFY for wet years; 2,500 AFY foraverage years; and a pump-back recovery of stored water of 5,000 AFY for dry years.• Increased artificial recharge by UWCD at El Rio and Saticoy based on projectedincreased capacity of the Freeman Diversion. With the addition of the Rose pit nearSaticoy, the projected artificial recharge ranges from 0 to 127,900 AFY.• Reduced average pumpage from the lower aquifer system by the City of Port Hueneme,the Channel Islands Beach Community Services District, and the U.S. Navy base atPort Hueneme for a combined reduction of as much as 1,000 AFY in lieu of newdeliveries of imported water from the State Water Project starting in January 1997.• Reduced pumpage by the PVCWD in lieu of 5,000 AFY of new surface-water deliveriesfrom the City of Thousand Oaks Hill Canyon wastewater treatment plant starting inJanuary 1998.All simulations of the proposed water supply projects reduced pumpage in the FCGMAareas, which resulted in a reduction, but not an elimination of, storage depletion and relatedcoastal landward flow (seawater intrusion) and subsidence. The objective of the potentialalternative water supply projects was to address these short-comings.Potential Alternative Water Supply ProjectsThe following potential alternative water supply projects were simulated and analyzed toassess their effectiveness at helping to manage the effects of increasing demand and variablesupply on the groundwater overdraft conditions:• Seawater Barrier (UAS) and Increased Pumpage in the Oxnard Plain Forebay• Artificial Recharge in Happy Camp Canyon• Eliminate Agricultural Pumpage in the South Oxnard Plain Subarea• Shift Pumpage to Upper Aquifer System in PTP Wells• Shift Pumpage to Upper Aquifer System in the Northeast Oxnard PlainW112003002SCO LW1458.DOC/ 033390002 68