The Peripheral Canal is a proposal to divert water from California's Sacramento River, around the periphery of the San Joaquin-Sacramento River Delta. It would transfer water into the California Aqueduct, North Bay Aqueduct, South Bay Aqueduct, and San Luis Canal via the Jones and Banks pumping stations, then be pumped to Central and Southern California (including San Francisco Bay Area water providers, like Santa Clara Valley Water District). Construction costs are estimated at between $3 and $17 billion, depending on the source. Freshwater flowing into the Delta displaces salt water entering from the bay. The freshwater/saltwater gradient has moved inland due to 5 to 7 million acre feet (6.2 to 8.6 km3) of water being exported each year to the Central Valley and Southern California. A peripheral canal would reduce the overall freshwater flow into the Delta and move the freshwater / saltwater interface further inland, causing damage to Delta agriculture and ecosystems.
Because of drought and other low flow issues that cause ocean water to flow far enough into the aqueducts of both the state (California Aqueduct) and federal government (Delta-Mendota Canal) from pumping stations which are located at the southern edge of the Sacramento–San Joaquin River Delta, drinking and irrigation water, as well as fish and waterfowl are in danger. For this reason, both state and federal agencies proposed a plan in 1965 for the second phase of the California State Water Project creating a canal that would transport fresh water from the Sacramento River around the delta, instead of through it.
Voters defeated a ballot initiative to build a similar Canal in 1982.
- Carle, David (2004). Introduction to Water in California. Berkeley, CA: University of California Press. pp. 42–43. ISBN 0-520-24086-3.
- Garone, Philip (2011). The Fall and Rise of the Wetlands of California's Great Central Valley. University of California Press. p. 242. ISBN 978052094849 Check