State Water Project
In 1960, California voters approved financing for construction of the initial features of the State Water Project (SWP). The project includes some 22 dams and reservoirs, a Delta pumping plant, a 444-mile-long aqueduct that carries water from the Delta through the San Joaquin Valley to southern California. The project begins at Oroville Dam on the Feather River and ends at Lake Perris near Riverside. At the Tehachapi Mountains, giant pumps lift the water from the California Aqueduct some 2,000 feet over the mountains and into southern California.
The SWP provides irrigation water to farms in the San Joaquin Valley, and is a major source of supply for cities in Los Angeles, Riverside, San Bernardino, San Diego, and other parts of southern California. In addition, the SWP serves cities in Napa and Solano counties through the North Bay Aqueduct, Santa Barbara and San Luis Obispo counties through the Coastal Aqueduct and communities in Alameda and Santa Clara counties through the South Bay Aqueduct. The project is operated by the California Department of Water Resources.
Other Major Water Systems
A number of large population centers in California have developed their own extensive water projects. The Hetch Hetchy Project transports Tuolumne River water 156 miles from the Central Sierra to San Francisco and peninsula cities.
The East Bay Municipal Utility District supplies cities on the east side of San Francisco Bay with Mokelumne River water.
Aqueducts built by the City of Los Angeles draw water from the Owens River, Mono Lake Basin and reservoirs on the east slopes of the southern Sierra. In Los Angeles, a 223-mile aqueduct completed in 1913 has served as a major water supply source, conveying water from the Owens River in the eastern Sierra. A second aqueduct, completed in 1970, added another 50 percent capacity to the water system. The two aqueducts deliver an average of 430 million gallons a day to the city.
