View File - Development Services - City of Oxnard

4.0 GREAT Program Project DescriptionThis section provides a description of the GREAT Program elements. As part of its waterresources master planning process, the City has determined that additional alternativewater supply sources should be developed to continue meeting the City's goal of providingcurrent and future residents and businesses with a reliable and affordable source of highquality water. Limitations on both the City’s local groundwater and imported watersources, plus the increased cost of imported water, prompted the City to conduct anadvanced planning study of alternative water supply sources. The study resulted in thedevelopment of the GREAT Program (proposed project), a water resources project thatcombines wastewater recycling and reuse, groundwater injection, storage and recovery, andgroundwater desalination to provide regional water supply solutions to water users in theOxnard Plain.4.1.1 BackgroundThe Oxnard Plain is one of several groundwater sub-basins within the coastal valleys andplains of the Santa Clara–Calleguas Basin in Ventura County, California. The Oxnard Plainis underlain by a complex aquifer system that has been the primary source of water suppliesin western Ventura County since the early 1900s (Hanson, 1992). Larger groundwater userson the Oxnard Plain include the City, UWCD Conservation District (UWCD), Port HuenemeWater Agency (PHWA), Ocean View Municipal Water District (OVMWD), and the PleasantValley County Water District (PVCWD). In addition to groundwater, other water supplysources on the Oxnard Plain include local surface water diverted from the Santa Clara Riverby UWCD for groundwater recharge and agricultural use, and imported water from theBay-Delta area of northern California, provided by Calleguas Municipal Water District.Since the beginning of groundwater development in the early 1900s, groundwater use hasresulted in water-level declines from 50 to 100 feet in the Upper Aquifer System (UAS) andLower Aquifer System (LAS) of the Oxnard Plain (Hanson, 1992). These declines havereduced the ability of the aquifer system to provide the required water supplies, and thesystem is in a state of overdraft. The Fox Canyon Groundwater Management Agency(FCGMA) was created in 1982 to manage and preserve these groundwater resources. TheFCGMA has adopted a number of ordinances in an effort to eliminate historic groundwateroverdraft and to combat the ongoing threat of seawater intrusion in both the Upper andLower aquifer systems. Through its Ordinance No. 8, FCGMA intends to reduce extractionsfrom the Oxnard Plain to a safe yield level of 120,000 acre-feet per year (AFY). Thisapproach is implemented through assigning groundwater pumping allocations to allgroundwater users in the Oxnard Plain (including the City, UWCD, and PHWA) based onhistorical extractions from 1985 to 1989.Imported water supplies from northern California are similarly limited, and supplies thatexceed current deliveries are expected to be increasingly costly in the future. The City ofOxnard GREAT Program will be implemented to address these water supply issues and todevelop the additional alternative water supply sources that the City has determined arenecessary as part of its master planning process.W112003002SCO LW1458.DOC/ 033390002 47