California State Water Project
The California State Water Project, commonly known as the SWP, is a state water management project in the U.S. state of California under the supervision of the California Department of Water Resources. The SWP is the world's largest publicly built and operated water and power development and conveyance system and provides drinking water for more than 23 million people and generates an average 6.5 million MWh of hydroelectricity annually. However, as the largest single consumer of power in the state, its net usage is 5.1 million MWh.
The original purpose of the project was to provide water for arid Southern California, whose local water resources were insufficient to sustain the region's growth. Construction began in the late 1950s, with major funding approved in a 1960 bond measure. The vote on the bond split along North-South lines, as Northern Californians opposed the measure as a boondoggle and an attempt to steal their water resources. Most of the water (roughly 80%) carried by the project is used for agriculture, primarily in the San Joaquin Valley, since pumping the water over the Tehachapi Mountains is costly and Southern California has other sources of water such as the Owens River, tributary creeks to Mono Lake and the Colorado River.
The primary features of the project include the Oroville Dam, the San Luis Reservoir, and the California Aqueduct. Northern California runoff from the Feather River, a tributary of the Sacramento River is stored in Oroville, Antelope, Frenchman and Davis Reservoirs, and released to the Sacramento-San Joaquin River Delta via the Sacramento River. The water is intercepted at Clifton Court Forebay, located at the southern end of the delta near Tracy, and lifted into the California Aqueduct via the C.W. "Bill" Jones (Tracy) Pumping Plant. The aqueduct travels south for about 100 miles (160 km) to the O'Neill Forebay, where up to one million acre-feet (0.81 km3) of water can be stored in San Luis Reservoir, an offstream facility shared with the federal Central Valley Project. From San Luis Reservoir the aqueduct continues south about 200 miles (320 km), supplying water to the San Joaquin Valley Westside. Near Kettleman City the Coastal Branch splits off from the main aqueduct. The Coastal Branch diverts a portion of the water southwest to Lake Cachuma, a reservoir located northwest of Santa Barbara, while the main branch continues southeast. South of Bakersfield, the aqueduct enters the Edmonston Pumping Plant, the largest pump-lift facility in North America, where the water is raised 1,970 feet (600 m) to cross the Tehachapi Mountains. Once clearing the crest of the mountains, the aqueduct splits again into East and West Branches. The West Branch travels southwest to feed a pair of reservoirs, Pyramid Lake and Castaic Lake, in the mountains north of Los Angeles. The East Branch continues southeast through the Mohave Desert before being pumped into Silverwood Lake and passing through Devil Canyon Powerplant, filling Lake Perris and providing supplemental water for Inland Empire cities.
In dry years, water pumped from the Delta creates a hazard to spring-run salmon, as the currents that the salmon spawn normally follow to the Pacific Ocean go to the pumps instead. This and other water use and environmental problems led to the creation of the CALFED Bay-Delta Program (CALFED) in 1994.
List of all facilities 
- Antelope Dam on Indian Creek in Plumas County, California
- California Aqueduct
- Castaic Dam
- Clifton Court Forebay
- East Branch California Aqueduct
- Elderberry Forebay
- Lake Palmdale on the California Aqueduct in Los Angeles County, California
- Oroville Dam on the Feather River in Butte County, California
- Pyramid Dam
- San Luis Dam (jointly operated with Central Valley Project)
- West Branch California Aqueduct
See also 
- Patrick D. McGee (1916–70), California State Assembly member who fought for the State Water Project
- Peripheral Canal
- Water in California
- State Water Project: Connecting California's Water
- California Department of Water Resources State Water Project overview
- State Water Project - Santa Clara Valley