The United Water Conservation District (United) works to maximize the water resources of the Santa Clara Valley and Oxnard Plain, utilizing the surface flow of the Santa Clara River and its tributaries for replenishment of groundwater. Enough water to supply the City of Oxnard for the next 100 years (more than 3 million acre-feet) has been reintroduced to the aquifers via this system. Many strategies and facilities have been developed over the years to provide for local demand while trying to reverse groundwater overdraft and seawater intrusion into coastal aquifers, and to balance this demand with increased need to provide water for environmental purposes.
United's facilities include
- The Santa Felicia Dam, constructed in 1955, was the first dam built to solely to recharge groundwater.
- The Freeman Diversion, constructed in 1991, replenishes approximately 58,000 acre-feet of stream flow to the underground water supply each year. A fish ladder was built into the Diversion to allow for the annual migration of steelhead trout.
- Lake Piru Recreation Area was created by the dam and holds approximentely 82,000 acre-feet of winter run-off while providing year-round camping, boating, fishing and other outdoor recreational opportunities to visitors.
- The Piru, Saticoy, El Rio and Noble Spreading Grounds (also known as artificial recharge basins) facilitate a natural percolation process, allowing water from the Freeman Diversion Facility to seep through layers of sand and gravel in an area known as the Oxnard Forebay to replenish the underground supply.
- The Pumping Trough Pipeline and the Pleasant Valley Pipeline and Reservoirs deliver surface water directly from the Santa Clara River to agriculture on the Oxnard Plain and Pleasant Valley to reduce pumping in the overdrafted lower aquifer system.
- The Oxnard- Hueneme Pipeline provides drinking water to the City of Oxnard, the Port Hueneme Water Agency and a number of mutual water companies. This avoids the necessity for local pumping near the coast where wells are most vulnerable to salt water intrusion.