The CVP stores about 13,000,000 acre feet (16 km3) of water in 20 reservoirs in the foothills of the Sierra Nevada, the Klamath Mountains and the California Coast Ranges, and passes about 7,400,000 acre feet (9.1 km3) of water annually through its canals. Of the water transported, about 5,000,000 acre feet (6.2 km3) goes to about 3,000,000 acres (12,000 km2) of irrigated agricultural fields, 600,000 acre feet (740,000,000 m3) supplies municipal uses, and 800,000 acre feet (990,000,000 m3) is released into rivers and wetlands in order to comply with state and federal ecological standards.
Two large reservoirs, Shasta Lake and Trinity Lake, are formed by a pair of dams in the mountains north of the Sacramento Valley. Water from both of these lakes are released into the Sacramento River, which flows to the Sacramento-San Joaquin Delta, at controlled rates. There, before it can flow on to San Francisco Bay and the Pacific Ocean, some of the water is intercepted by a diversion channel and transported to the Delta-Mendota Canal, which conveys water southwards through the San Joaquin Valley, supplying water to San Luis Reservoir (a SWP-shared facility) and the San Joaquin River at Mendota Pool in the process, eventually reaching canals that irrigate farms in the valley. Friant Dam crosses the San Joaquin River upstream of Mendota Pool, diverting its water southwards into canals that travel into the Tulare Lake area of the San Joaquin Valley, as far south as the Kern River. Finally, New Melones Lake, a separate facility, stores water flow of a San Joaquin River tributary for use during dry periods. Other smaller, independent facilities exist to provide water to local irrigation districts.
San Joaquin River
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