Salinity Management in Urban Southern California

The State of California created the Metropolitan Water District of Southern California in 1928 to provide supplemental water supplies to the rapidly developing urban areas of the coastal plain. Today, Metropolitan's service area encompasses virtually all of the Los Angeles and San Diego metropolitan regions, with a population of nearly 17 million. In total, annual water demands placed on all sources within Metropolitan's service area were approximately 3.8 million acre-feet in calendar year 1997. Water supplies for this 5,200-square-mile area come from an array of sources, including local surface and groundwater supplies, as well as the imported supplies from the City of Los Angeles' aqueduct system and Metropolitan's supplies from the Colorado River and Northern California. About 47 percent or 1.8 million acre-feet of the total demand was met from Metropolitan's supplies. In addition, aggressive local programs among Metropolitan's 27 member public water agencies and over 300 subagencies heavily promote groundwater conjunctive use programs, and reclamation programs for reuse of supplies. Approximately 1.6 million acre-feet of local demands are met by these two sources.