Water Supply
• The State Water Resources Control Board may intervene if locals do not form a GSA and/or fail to adopt and implement a GSP.
Ventura County’s groundwater basins
Ventura County’s water purveyors and their service areas
Major Ventura County water districts
A. No. East County cities, such as Simi Valley and Thousand Oaks, depend exclusively on state water imported from Northern California. In the West County, cities such as Ventura, Santa Paula, Fillmore and Ojai receive no imported water and rely entirely on local supplies. In the central part of the county, communities such as Camarillo and Oxnard rely on a blend of local and imported supplies.
A. Agriculture accounts for about 56 percent of Ventura County’s water demand. Cities use about 43 percent.
A. It depends on weather, soil type, location, type of crop and maturity of the plants. But on average, it takes about 3 acre-feet per acre per year to properly irrigate mature orchards and long-season crops such as berries. Crops that mature relatively quickly, such as most vegetables, typically need only 1 to 2 acre-feet per acre during the growing season, but there generally will be several crops planted each year on the same piece of ground.
A. Total annual water demand for cities and farms is about 445,000 acre-feet. An acre-foot is 325,900 gallons, or about enough for two average household for a year.
A. Most growers use high-efficiency drip or micro-sprinkler irrigation systems to minimize runoff and reduce waste. Many have also installed technologically sophisticated soil moisture sensors and computerized irrigation management systems to carefully calibrate plant water needs. Orchard owners also use mulch to control weeds and aid in moisture retention.
A. In a typical year, local groundwater provides 85 percent of the supply used for agricultural irrigation in Ventura County. Local surface water accounts for about 9 percent, and recycled wastewater supplies about 4 percent. Only 2 percent of the agricultural water supply is derived from imported water, which is much more expensive than local surface and groundwater.