Los Angeles Aqueduct

The Los Angeles Aqueduct system, comprising the original Los Angeles Aqueduct from the Owens Valley and the Second Los Angeles Aqueduct, is a water conveyance system built and operated by the Los Angeles Department of Water and Power under chief engineer William Mulholland, carrying water from the Owens River in the eastern Sierra Nevada to the city of Los Angeles. Its construction was controversial from the start because the diversion of water eliminated the Owens Valley as a viable farming community, and a clause in the city's charter barring the sale of surplus water outside the city pressured neighboring communities into annexation. The system included the St. Francis Dam, completed in 1926 to provide storage, whose collapse two years later killed at least four hundred thirty one people, slowed annexation, and led to the creation of the Metropolitan Water District of Southern California to build the Colorado River Aqueduct. The aqueduct's continued operation remains the subject of public debate, legislation and litigation over its environmental effects on Mono Lake and other ecosystems.