In 1920, work began on a plan for a statewide water development project. Implementation of the “State Water Plan” was authorized by the legislature and $170 million in bond funding was approved by the voters in 1933. However, due to the Great Depression, the state was not able to market the bond funds. The federal government stepped in to develop the Central Valley Project (CVP) as a public works project to provide jobs.
It was originally constructed for three purposes: flood control and navigation; water for irrigation and domestic use, and power generation. In 1992, the Central Valley Project Improvement Act added additional purposes– recreation, fish and wildlife enhancement, and water quality improvements.
Constructed and operated by the U.S. Bureau of Reclamation, the CVP is one of the largest water storage and transport systems in the world, storing and distributing about 20% of the state’s developed water, about 7 million acre-feet. It consists of a massive system of reservoirs and canals and generates over 5 billion kilowatt hours of energy in an average year. Water is transported 450 miles from Lake Shasta in northern California to Bakersfield in the southern San Joaquin Valley. The CVP provides water for nearly 2.5 million Californians and more than 3 million acres of farmland.
The Santa Clara Valley Water District executed a contract with the Bureau of Reclamation to receive CVP water in 1977 and received its first deliveries in 1987. CVP water comes through the Delta to C.W. “Bill” Jones Pumping Plant in Tracy, and then travels south through the Delta Mendota Canal to San Luis Reservoir. From there, the water is diverted through the Pacheco Tunnel to the Pacheco Pumping plant, and then through pipelines to Santa Clara County.
The district has a contract to receive 152,500 acre-feet per year from the CVP. (One acre-foot is approximately the amount of water used by two families of five in one year.)
Each year, water agencies that have contracts with the CVP are allocated a percentage of their contract amount depending on rain and snowfall amounts, regulatory restrictions to protect fish and water quality, as well as other factors.
Unlike SWP contracts, the allocations of CVP water supplies depends on the purpose of use. Up to 130,000 AF of the district’s CVP water supply is given a higher priority for municipal and industrial (M&I) use. At present, the long-term average allocation of these M&I supplies is estimated to be 75% of the M&I contract amount, which represents the district’s largest and most reliable source of imported water.
The long-term average allocation of the remaining CVP contract amount used for agricultural irrigation is estimated to be roughly 43%.
Taking into account various adjustments, the district’s long-term average deliveries from the CVP are estimated to be approximately 110,000 AF.
For more information about the Central Valley Project, visit the U.S. Bureau of Reclamation website.