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The California State Water Project (SWP) is a water storage and delivery system of reservoirs, aqueducts, power plants and pumping plants. It extends for more than 600 miles, two-thirds the length of California.

Planned, constructed, and operated by DWR, the SWP is the largest state-built, multi-purpose water project in the U.S. It provides water supply to more than 25 million Californians in Northern California, the Bay Area, the San Joaquin Valley, the Central Coast and Southern California. The system also provides flood control, power generation, recreation, fish and wildlife protection, and water quality improvements in the Sacramento-San Joaquin Delta.

In 1951, the Legislature authorized what is now the State Water Project. Construction began on facilities at Oroville in 1957, and in 1960 voters approved a $1.75 billion bond act to build the initial SWP facilities. Work began on the California Aqueduct in 1963 and by 1968, the SWP was able to deliver water to the San Joaquin Valley. By 1973, the initial facilities were completed to allow water delivery to Lake Perris in Riverside County, the southernmost point in the system. Costs for water development and delivery are paid by the SWP water supply contractors, 29 local and regional water agencies.

As major SWP facilities were being planned, designed and constructed, features to mitigate impacts to and provide enhancement for fish and wildlife were also incorporated. Some forward-thinking features, such as the multiple-level outlet structure at Oroville Dam, that help water managers control water temperature for fish, demonstrated the SWP’s commitment to the environment from its earliest days.

Today, the job of balancing environmental concerns and moving water has grown exponentially. Over the past 50 years, environmental stresses have greatly increased and compliance with regulations such the California Environmental Quality Act and the Federal and California Endangered Species Acts has added complexity to the SWP’s multipurpose operations. Adapting California’s water management systems to climate change presents one of the most significant challenges for the State Water Project.

More about the State Water Project


The State Water Project uses the "Notice to State Water Project Contractors" as a format to provide key information regarding SWP water allocations, water supply programs, billing information, and other administrative issues. The list below contains notices starting with the January 10, 1996 notice and ending with the most recent notice to date.

More about Water Deliveries


The Operations Control Office directs overall water and power operations of the California State Water Project.

More about Operations Control Office


The State Water Project’s Oroville Facilities are operated in part pursuant to a license issued by the Federal Energy Regulatory Commission (FERC). The original license for the Oroville Facilities was issued on February 11, 1957. For the past decade, DWR has been engaged in an extensive and collaborative process with state, federal and local agencies, stakeholders, the State Water Contractors, and other interested parties to renew the federal license from FERC that will allow DWR to continue generating hydroelectric power while continuing to meet existing commitments and complying with regulations pertaining to water supply, flood control, the environment, and recreational opportunities.

More about Oroville Facilities Relicensing

Complete List of Other State Water Project Topics