Wirtz Dam on Lake LBJ. The Lower Colorado River Authority is starting a $76 million, three-year project to replace the 10 floodgates at the dam. LCRA photo
The Lower Colorado River Authority is starting a $76 million, three-year project to remove and replace the 10 floodgates at Wirtz Dam on Lake LBJ to help ensure the dam continues to operate safely and reliably for years to come, the authority announced in a media release Wednesday, Jan. 18.
The dam was completed in 1951 and has nine original floodgates and a 10th floodgate that was added when the first Thomas C. Ferguson Power Plant was built in 1974. Each floodgate will be carefully removed and replaced with a new custom-made floodgate that meets today’s engineering standards, the LCRA said.
Work will be done on one floodgate at a time to ensure the dam remains operational and available to pass floodwaters downstream.
“We could do this project more quickly if we replaced multiple floodgates at once, but we are in Flash Flood Alley and that is not a viable option,” said John Hofmann, LCRA’s executive vice president of Water, in the LCRA media release. “Dams along the Highland Lakes play a critical role in managing floodwaters, and we have to maintain their readiness at all times.”
The LCRA expects work on each floodgate to take about two months and the entire project to be finished in 2025.
In addition to replacing the floodgates, crews will upgrade the machinery, called hoists, that lifts them. Two hoists will be replaced and eight will be refurbished. The existing hoist bridge also will be replaced.
During the project, the area immediately upstream of Wirtz Dam on Lake LBJ that is off-limits to boaters will be expanded by about 150 feet to about 300 feet to allow construction crews ample room to remove and replace the floodgates. A buoy line will be in place to cordon off the construction area.
The new, 120,000-pound floodgates will be assembled in an area south of the dam and then moved via construction barges and cranes.
Construction crews preparing the laydown yard will be in the area starting in late January. Heavy equipment is expected to begin arriving in mid-February. Installation of the first floodgate is planned to start in April.
Since fiscal year 2010, the LCRA has invested more than $134 million in capital projects at dams along the Highland Lakes, Lake Bastrop, and Lake Fayette, including on the structures themselves and related hydroelectric generation infrastructure. The authority plans to invest more than $107 million in these types of projects over the next five years.