Lake Austin, just below Mansfield Dam.
LCRA operates six dams on the lower Colorado River in Central Texas: Buchanan, Inks, Wirtz, Starcke, Mansfield and Tom Miller. These dams form the six Highland Lakes: Buchanan, Inks, LBJ, Marble Falls, Travis and Austin.
Each of the dams was built to manage floods, but Mansfield Dam, which forms Lake Travis, is the only one designed to hold back floodwaters.
Between 1843 and 1938, the river basin suffered 15 major floods, causing millions of dollars in damage. Since their completion in 1942, Mansfield Dam and Lake Travis have protected downstream residents by reducing flood impacts.
Lakes Travis and Buchanan also serve as water supply reservoirs. The lakes hold water during wet times for use during dry times. The water supply supports more than 1 million people as well as businesses, industries, the environment and, when available, agriculture in the lower Colorado River basin.
The combined storage capacity of lakes Travis and Buchanan is about 655 billion gallons.
The dams in the Highland Lakes chain have hydroelectric generation stations that contribute to the Central Texas energy supply. Together, the hydroelectric plants at the dams can provide more than 295 megawatts of electricity per year.
Hydroelectricity was once the major source of power for LCRA's electric service area, but hydroelectric generation now is primarily a byproduct of other river operations. Water is moved through hydroelectric generation solely to create power at the request of the Electric Reliability Council of Texas during a power emergency.