Surface Water Reservoirs and Rainfall Enhance Water Reliability
Across the San Diego region, two dozen surface water reservoirs serve a variety of purposes, including storing imported water and capturing runoff from local rainfall. On average, the semi-arid San Diego area receives just over 10-inches of rain annually as measured at the Lindbergh Field weather station situated on the coast – while inland mountain areas can receive more than three times this amount of rainfall.
Runoff from seven watersheds in the county supply 24 reservoirs – that have a combined capacity of about 723,000 acre-feet. In addition, the region’s ratepayers have invested in reservoirs owned by the Metropolitan Water District of Southern California, and the Water Authority is seeking a storage account in Lake Mead as a low-cost way to increase reserves and provide water to this federal drought-stricken reservoir.
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Historical Data

Reservoirs
Across the San Diego region, two dozen surface water reservoirs serve a variety of purposes, including storing imported water and capturing runoff from local rainfall.

Rainfall
On average, the semi-arid San Diego area receives just over 10-inches of rain annually as measured at the Lindbergh Field weather station situated on the coast.