Water Education Foundation

The Los Angeles Aqueduct

Posted by: Maven on August 19, 2008 at 3:27 pm

Owned and operated by the Los Angeles Department of Water and Power, the Los Angeles Aqueduct supplies a portion of the water needed to supply the residents and businesses in its 465 square mile service area. The Los Angeles Aqueduct system includes 8 storage reservoirs along the aqueduct, and 99 reservoirs and tanks located within the city.

The Los Angeles Aqueduct system delivers water 338 miles from the Mono Basin and 233 miles from the Owens Valley by gravity to Los Angeles. The first Los Angeles Aqueduct was completed in 1913. It took five years to build at a cost of $23 million.

Water from the Owens Valley travels through 24 miles of unlined open channels, 37 miles of lined open channels, 97 miles of concrete conduit, 43 miles of tunnels, 12 miles of steel and concrete pipe, 8 miles of reservoirs, 2 miles through the Haiwee bypass, and 10 miles through power tunnels and waterways to reach Los Angeles. The second Los Angeles Aqueduct was completed in 1970 at a cost of $89 million, and utilizes a mix of concrete conduit and steel pipelines.

In the year 2005-2006, the Owens Valley supplied 48% of the water for DWP; Metropolitan Water District of Southern California supplied 41%, groundwater sources provided 11%, and only 1% was recycled. About 72% of water use in DWP’s service area is for residential use; 25% is for commercial & government, and 3% is for industrial use.

In order to acquire the necessary water rights, during the early part of the twentieth century, the city purchased much of the land in the Owens Valley. To this day, DWP still remains the largest private land owner in the Owens Valley area. LADWP owns 314,000 acres, primarily on the Owens Valley floor. Of this, 260,000 acres are leased back to residents mostly for ranching, with a small portion leased for commercial or recreational use. LADWP leases the land for ranching under strict guidelines designed for maximum protection of the watershed.

The dewatering of the Owens Valley has not been without its ill effects on the Owens Valley and on Mono Lake. The export of water south to Los Angeles decimated a thriving agricultural community, dried up Owens Lake, and turned parts of the Owens Valley into a desert. Environmental mitigation for the damage done has been litigated for decades, and currently, DWP is under court mandated obligation to keep water in the Lower Owens River and provide dust control on the dry Owens Lake bed.

Furthermore, DWP is prevented from diverting water from the Mono Lake Basin until the lake level reaches a mandated elevation – which is a long way off. This has resulted in a reduction in the amount of water that DWP can export from the Owens Valley.

Some say that Los Angeles stole the water from the Owens Valley, and whether this is true or not is a subject of debate. Others say that the land management policies of the DWP have discouraged extensive urban development, and have thusly spared the Owens Valley the problems associated with increased urbanization. To this day, Inyo County remains one of California’s least populated counties. The area is a popular recreation destination, offering camping, fishing, hiking, rock climbing, and many other outdoor activities. More on these issues in the Aquafornia article, California’s Water Crisis.

Picture Tour Of La Aqueduct
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