The combined storage in lakes Buchanan and Travis sits at 698,913 acre-feet, about 35 percent of the full capacity, but the Lower Colorado River Authority is preparing Mansfield Dam and other dams of the Highland Lakes for flooding. "It is going to flood again. History tells us that, and we are getting ready for it," said Ryan Rowney, LCRA vice president of water operations. "It could happen tonight or it could happen months from now, but it is going to happen." LCRA launched a 10- to 11-year, more than $10 million plan to completely overhaul the dams 24 floodgates in late 2014, the first time the gates have been overhauled in the more than 70-year history of the dam, which was completed in 1942. "We do regular maintenance of the floodgates every 42 days or so," Rowney said. "We are very diligent about maintenance."

Removing the gates

The floodgates are removed and repaired one at a time, leaving the remaining 23 gates to operate in the rare-chance of a flood, Rowney said. "The most floodgates we have ever had open at one time was six back during the 1991 Christmas floods," he said. Because of the severely confined area inside the dam the gates are manually lifted 1/8 of an inch with every 4-foot pull of the original chain lifts, energy services mechanic Eric Spurlock said. The 50,000-pound gates are then loaded onto a railroad-type cart and shipped off for repairs, Rowney said. Rowney said each gate costs about $600,000 and takes six to eight months to repair. The majority of the repair work is done at LCRA facilities, such as the Fayette Power Projects machine shop. "The first gate was a bit of a learning curve," he said. "The guys who originally put the gates in aren't around anymore. Now that we have done one gate we anticipate the process will go a little quicker and cost a little less." Kara Gilliland, an owners representative with Construction Services, said there are more than 5,000 working parts and pieces on one gate. "It is a once-in-a-lifetime opportunity," she said. "You go in and pull out a gate that hasn't been pulled out in since the dam was built. Its exciting." Because the floodgates are located at the bottom of the dam and are underwater, each must be capped before it can be removed. Divers are routinely used to make sure no brush or debris is blocking the gates, Rowney said.

Area effect

The project, which was budgeted and paid for as a capital improvement project by LCRA, will not affect local water prices and outside of a monthly parts delivery, should have a minimal effect on traffic on RR 620, Rowney said. "Folks wont even know what is going on," he said. "All the work is done in the bowels of the dam." Senior Project Manager Monica Masters said it is very important that even though the gates work now, LCRA makes sure the gates continue to be properly maintained. "These gates need to work like they were designed to, that way when we do get that next flood which is going to happen someday they are ready to go and operate exactly how they were designed in the 40s." The Mansfield Dam work is part of a project to work on all six of the dams of the Highland Lakes.