Los Angeles Aqueduct

The Los Angeles Aqueduct system, comprising the Los Angeles Aqueduct (Owens Valley aqueduct) and the Second Los Angeles Aqueduct, is a water conveyance system, built and operated by the Los Angeles Department of Water and Power. The Owens Valley aqueduct was designed and built by the city's water department, at the time named The Bureau of Los Angeles Aqueduct, under the supervision of the department's Chief Engineer William Mulholland. The system delivers water from the Owens River in the eastern Sierra Nevada mountains to Los Angeles. The aqueduct's construction was controversial from the start, as water diversions to Los Angeles eliminated the Owens Valley as a viable farming community. Clauses in the city's charter originally stated that the city could not sell or provide surplus water to any area outside the city, forcing adjacent communities to annex themselves into Los Angeles. The aqueduct's infrastructure also included the completion of the St. Francis Dam in 1926 to provide storage in case of disruption to the system. The dam's collapse two years later killed at least 431 people, halted the rapid pace of annexation, and eventually led to the formation of the Metropolitan Water District of Southern California to build and operate the Colorado River Aqueduct to bring water from the Colorado River to Los Angeles County. The continued operation of the Los Angeles Aqueduct has led to public debate, legislation, and court battles over its environmental impacts on Mono Lake and other ecosystems.