California & Arizona
A concrete arch-gravity dam that crosses the Colorado River 155 miles (249 km) downstream of Hoover Dam. Built between 1934 and 1938 by the Bureau of Reclamation, it is 320 feet (98 m) high, 235 feet (72 m) of which are below the riverbed, making it "the deepest dam in the world". The dam's primary functions are to create a reservoir, and to generate hydroelectric power. The dam straddles the border between California and Arizona. The reservoir behind the dam is called Lake Havasu and can store 647,000 acre·ft (798,000 dam³) or over 210 billion US gallons.
The total system consists of more than 2800 miles of transmission lines serving 40 power substations managed by a Central System Dispatching Office in Phoenix, Arizona. The installed generating capacity of Colorado River projects managed by Western is about 3000 megawatts -- enough energy to provide electric service for a year to more than two million homes. More than 9.5 billion kilowatt-hours of Colorado River hydroelectric energy is marketed each year, resulting in annual revenues to the U.S. Treasury of more than $140 million.
Parker Dam Penstock Intakes
Power Turbine from Parker Dam
In addition to its water storage and power producing capabilities, Parker Dam also performs other functions. It provides flood control by capturing and delaying flash floods discharged into the river from tributaries below Davis Dam. It reregulates water releases from Hoover and Davis power plants, smoothing the Colorado's flow for the benefit of downstream water users. Self-Guided Tour Canceled as of June 1997.
Parker power plant, located on the California side of the Colorado River immediately below the dam, houses four hydroelectric generating units. Each unit can produce 30,000 kilowatts of non-polluting hydroelectric power. Four 22-foot-diameter pipes called penstocks can each carry up to 5500 cubic feet of water per second (over 41,000 gallons) to feed the generating units. About 50 percent of the plant's power output is reserved by the Metropolitan Water District of Southern California (MWD) for pumping water through the Colorado River Aqueduct to the Pacific Coast. The remaining power is marketed by the Western Area Power Administration.