SAN DIEGO (AP) - For San Diego's regional water agency, its largest supplier is also its biggest adversary.
A trial beginning Tuesday in San Francisco will test the San Diego County Water Authority's claim that its customers subsidize nearly all the rest of Southern California.
Its lawsuit against the Metropolitan Water District of Southern California brings to a head a long-running dispute, and the outcome may affect the pocketbooks of 19 million people.
The San Diego agency says Los Angeles-based Metropolitan overcharges for bringing Colorado River water to the Pacific Coast on its 242-mile aqueduct.
Metropolitan is accused of using the supposed windfall to give lower rates to cities and agencies in in Los Angeles, Orange, Riverside, San Bernardino and Ventura counties.
Metropolitan is fighting the lawsuit.
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