Related links: QuickTime* video on the dam modernization project | Fact sheet on dam upgrades
AUSTIN — LCRA and community representatives from throughout Central Texas today (Jan. 12) celebrated an advance in public safety — the completion of a 10-year, $52 million project to ensure the stability of the six Colorado River dams upstream of Austin.
The project strengthened and anchored the four Highland Lakes dams that, engineering studies showed, needed modernization to withstand the worst flood considered possible in the lower Colorado River basin. They are Tom Miller Dam, which forms Lake Austin; Wirtz Dam, which forms Lake LBJ; Inks Dam, which forms Inks Lake; and Buchanan Dam, which forms Lake Buchanan. The other two dams, Mansfield and Starcke, did not require upgrades.
Although the chance of such a severe storm is one in 10,000, according to the U.S. Army Corps of Engineers, the dense population around the lakes and river made it especially urgent to upgrade the dams. LCRA passes floodwaters through the dams and lakes to Lake Travis where a flood pool formed by Mansfield Dam stores the water until it can be safely released downstream.
"This is a highlight of LCRA's 70-year history of carrying out a basic responsibility to minimize the impact of floods on riverside communities," said LCRA General Manager Joe Beal. The dam modernization project is a success because it improves public safety and because it was completed five years ahead of schedule and more than $6 million under the original $58.5 million budget, Beal said.
It took 110 miles of steel cable to anchor the dams to the bedrock of the Colorado River. Increasing the mass of the dams took 665 million pounds of concrete, enough to fill The University of Texas at Austin football field to a height of 140 feet. The weight of the concrete is equal to 220,000 full-size automobiles.
"This massive undertaking has truly life-saving ramifications," said Austin Mayor Will Wynn. "Before this project, Tom Miller Dam was vulnerable to breaching during very severe storms. Since it stands between Lake Austin and Town Lake, a failure would have caused great harm to businesses, residences and potentially human life. Now we do not have that concern."
The Highland Lakes are important to communities, including Austin, as sources of drinking water for more than a million people. LCRA uses the hydroelectric power generators at each dam as sources of renewable energy.
"This is more than a matter of safety," said Ray A. Wilkerson, chair of the LCRA Board of Directors. "The lakes formed by the dams help make Austin and other river communities attractive places to live. The lakes play a major role in sustaining the region's economy. This project ensures that the dams will continue to be a valued asset to the people of Texas for decades to come."
More needs to be done by LCRA and communities to reduce the risk of damages from floods, Beal said. LCRA will continue to improve its flood management and information system, including Hydromet gauges that provide real-time information on rainfall and water flow, he said. The other element of public safety, floodplain management, is the responsibility of local governments.
"Steel, concrete and technology will not fully protect people who live or build in the floodplain," Beal said. He commended the Texas Colorado River Floodplain Coalition, an organization of more than 50 communities, for its efforts to improve floodplain management through education, decisions about development in floodplains, emergency communication and planning, and federal studies to identify floodplains more accurately.
"LCRA, its customers and the communities share a common goal that when the big floods come they will do so without harm to lives and property," Beal said. "Dam modernization is a step toward that goal, but there is more to be done. Together we can make this region an even safer place to live."
*The video requires Apple QuickTime to view. Download the free program. |
