The Los Angeles Aqueduct 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. Built between 1908 and 1913 at a cost of $23 million, the LA Aqueduct tapped into the waters of the Owens River and delivered water 233-miles south to Los Angeles. When completed in 1913, the Los Angeles Aqueduct was considered to be a great engineering accomplishment only second to the Panama Canal. A century later, it continues to be a marvel in modern engineering. The LA Aqueduct brought water from the Owens Valley hundreds of miles away to a growing area in need of additional resources to sustain its people and their endeavors, helping spur an economy that today rivals that of many nations. A century later, this gravity-fed system continues to be a major source of water for Los Angeles — on an average year supplying 29% of the water needs for four million people.