We’re at the end of a very long pipeline

For more than 70 years, the San Diego County Water Authority has imported water to meet the San Diego region’s needs through times of drought, economic expansion, and population growth. The San Diego region’s reliance on imported water is not surprising given its semi-arid climate and periodic droughts.

The county has relied on Colorado River water since 1946. The San Diego region has significantly increased control over those supplies with the historic Quantification Settlement Agreement of 2003. These highly reliable supplies include a water conservation and transfer agreement with the Imperial Irrigation District and water conserved by lining long stretches of the All-American and Coachella canals.

The county also receives imported water from the Sacramento-San Joaquin Bay-Delta via the State Water Project. While water from the Bay-Delta is a critical resource, San Diego County is reducing reliance on it due to environmental and water supply challenges. 

Imported Water Sources

colorado river aerial view
Colorado River

The Water Authority joined the Metropolitan Water District of Southern California in late 1946, gaining a connection to the Colorado River. Water from the river reached San Vicente Reservoir near Lakeside a year later, via San Diego Pipeline 1 and the Colorado River Aqueduct.

northern califoria water source
State Water Project

Water from Northern California comes via the State Water Project and MWD. The Sacramento-San Joaquin Bay-Delta is the hub of the State Water Project. Efforts have been made in recent years to address the Bay-Delta’s complex environmental and water supply challenges.