Wirtz Dam next on floodgate upgrade list

A close-up shot of a few of the 37 floodgates on Buchanan Dam that were recently upgraded. The new gates can be opened quickly and with much less personpower than the older gates in response to floods. Courtesy photo
Now that the 37 floodgates on Buchanan Dam have been upgraded, the Lower Colorado River Authority has moved on to improving the floodgate functions at Alvin J. Wirtz Dam, which forms Lake LBJ. Currently in the design phase, construction is expected to begin in the fall of 2022 and will take two to three years to complete.
The LCRA spent 12 years and $51 million renovating Buchanan Dam, which is 83 years old and the largest in the chain of Highland Lakes.
Tom Miller’s nine floodgates were completed first, in 2020, at a cost of $10.8 million. The project took 22 months.
Water sales pay for these and other capital projects along the Highland Lakes, Lake Bastrop, and Lake Fayette, said John Hofman, LCRA’s executive vice president of water. The LCRA recently raised its firm water rates by $10 an acre-foot, effective January 2022.
Since fiscal year 2010, LCRA has invested more than $110 million in capital water projects. It plans to invest about $64 million more in dam rehabilitation and maintenance over the next five years, including at Wirtz and Max Starcke dams. Max Starcke Dam divides Lake Marble Falls and Lake Travis.
Floodgate improvements could result in a 2-foot increase in the maximum lake level at Lake Buchanan from 1,018 feet to 1,020 feet.
“A lot of time and effort went into raising and lowering those gates,” Hofman said of the older versions, which were built in the 1930s. “We had two sets of hoists for each of the three gate sections. You had to go in and move a hoist over a gate, pull the gate up, lock it out, disconnect the hoist, and do it all over again. It takes a few people some time to do that.”
The new gates allow for off-site activation, although someone always will be on site to make sure conditions are clear for opening floodgates, Hofman continued.
“The FEMA agreement had us operating with a maximum lake level of 1,018 because they were concerned that under a significant flooding event, especially if it was full at 1,020, we could not open the gates fast enough to safely operate the dam,” he said. “You couldn’t open them fast enough to keep water from going over the spillway.”
The new floodgates alleviate that problem and allow for more water in the reservoir during non-drought conditions, something Burnet County Judge James Oakley has long advocated.
“Burnet County requests that LCRA change its operations of Lake Buchanan to store water up to 1,020 feet msl (maximum sea level) year-round, when water is available and not needed to meet downstream demand,” Oakley wrote in a letter dated July 23, 2015, to LCRA General Manager Phil Wilson. “It is our belief the conditions have changed substantially such that a re-examination of the 1990 FEMA agreement is warranted.”
It has taken a while, but the negotiations between the LCRA and FEMA can now get underway. Nothing is going to happen quickly, though, Hofman said.
“As of right now, FEMA’s agreement is still in place,” he told DailyTrib.com. “Our mode of operation remains what it is. I would anticipate it would take us some time to approach FEMA.”
The maximum sea level at Lake Buchanan was lowered to 1,018 feet from 1,020 feet in the 1980s. When Oakley formally requested it be increased again to 1,020 feet, he said the LCRA agreed but told him the work on the floodgates had to be completed first.
“I get it. They had to wait until all that work was done before going through the process with FEMA,” Oakley said.
Oakley’s concerns include lakefront property owners and tourism to the area.
“Think of it as a battery fully charged,” he said. “When release is necessary for the rice farmers downstream, the impacts of drawdown are less. That’s 43,000 acre-feet. That’s a lot of water. You want to keep it full. To me, it was just one of those things that needed addressing.”
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LCRA,
Will the water level on lake LBJ be affected with the upgrade renovation on Wirtz dam ?