View File - Development Services - City of Oxnard

WATER RESOURCES TECHNICAL REPORT2.2 Water Resources Management2.2.1 United Water Conservation DistrictUWCD manages the surface water and groundwater resources over an area encompassingabout 330 square miles covering the downstream portion of the Santa Clara River valleyand the Oxnard Plain area. The UWCD service boundary, groundwater basins within theSanta Clara-Calleguas Basin, and major recharge and conveyance facilities within theUWCD service boundary are shown in Figure 2-3. The UWCD boundary encompasses thearea that would be affected by the GREAT Program. UWCD, originally formed by locallandowners in 1927 as the Santa Clara River Water Conservation District, was created in1950 to address groundwater overdraft issues. UWCD administers a basin managementprogram for the Santa Clara Valley and Oxnard Plain, utilizing surface flow from theSanta Clara River and its tributaries for replenishment of groundwater. UWCD facilities,which are further described in Section 3.0, include Santa Felicia Dam and Lake PiruRecreation Area; Piru, Saticoy, and El Rio Spreading Grounds; Pleasant Valley pipeline andreservoirs; Oxnard-Hueneme (O-H) pipeline, pumping plant and pumping-trough pipeline;and other facilities.2.2.2 Fox Canyon Groundwater Management AgencyGroundwater resources within the Oxnard Plain, Pleasant Valley, Las Posas Valley, andSanta Rosa Valley are managed by the FCGMA, which was created in 1982 to preservegroundwater resources for water users in all areas overlying the Fox Canyon aquifer zone.The FCGMA has jurisdiction over groundwater resources located beneath all land thatoverlies the Fox Canyon Aquifer, which encompasses approximately 185 square miles. TheFCGMA manages groundwater resources through ordinances and does not own any capitalfacilities. Ordinance No. 5, adopted in 1990, is the most significant ordinance adopted by theFCGMA. Ordinance No. 5 addresses groundwater overdraft by requiring reductions ingroundwater extractions via scheduled 5 percent reductions beginning in 1990 every 5 yearsthat will total 25 percent by 2010. The objective is to reduce extractions to a "safe yield" levelby 2010. The reductions are based on actual pumping records during the 5-year “base”period from 1985 through 1989. Funding for FCGMA operations is based on extractioncharges by pumpers within the agency boundary. Ordinance No. 5 has been superceded byOrdinance No. 8 adopted in 2002.2.2.3 United States Geological SurveyThe USGS, in partnership with the FCGMA, other water purveyors on the Oxnard Plain,and numerous other well owners, has performed several studies to assist with managementof groundwater resources within the Santa Clara-Calleguas Hydrologic Unit. These studiesare part of the ongoing Southern California Regional Aquifer System Analysis (RASA)Program. The purpose of the RASA Program has been to analyze the major issues affectinggroundwater use in Southern California, including groundwater overdraft, stream-flowdepletion, subsidence, seawater intrusion, and groundwater contamination. The SantaClara-Calleguas Basin was selected as the typical “coastal” groundwater basin for thisstudy. In 1984 to 1985, the USGS designed and installed a series of clustered monitoringwells along the Oxnard Plain to provide water level and water quality data specific to eachW112003002SCO LW1458.DOC/ 033390002 7