Officials expect to complete rehabilitation of a “high-hazard” dam in east Kyle, which has closed a portion of Goforth Road for roughly two years, in April or May.
The upgrade, which was budgeted for $7.95 million, is part of the Plum Creek Conservation District’s (PCCD) effort to meet state safety standards, said Johnie Halliburton, executive manager of the PCCD.
PCCD’s Soil Conservation Site 6 dam, located on Goforth Road, was built in 1967 as an earthen structure meant to hold Porter Creek, a tributary of Plum Creek, into a reservoir. Overflow drainage was meant to flow around the dam and back into Porter Creek.
The dam was built where Beebe, High and Goforth roads all converge.
However, the Site 6 dam was labeled as having a “high-hazard potential” by the Texas Commission on Environmental Quality (TCEQ) in 2002. The TCEQ, which oversees all dams in Texas, determined a possibility of a high loss of life and high economic damage could be caused downstream in the event of a dam failure.
In 2015, the PCCD moved forward with plans to rehabilitate the dam. Halliburton said the high hazard designation, along with need for rehabilitation, came as a result of the rapid growth near the dam. However, Haliburton said in an emailed response the classification “does not reflect the condition or maintenance of the dam.”
Dams are classified based on the population below the structure, several different risk indexes and the probable maximum flood (PMF), which is the largest flood that could conceivably occur based on the most severe hydrologic and meteorological conditions.
“When it was built, it was built as a low-hazard dam,” Halliburton said. “With all of the population growth downstream, and because it was high on the list for the state to be upgraded, it’s being rehabbed to meet state safety requirements.”
The PCCD began construction in 2016 of a new concrete structure that features a labyrinth weir, which will allow any potential overflow water to go over the top of the dam and allow more surface area to travel. The water would then be diverted back into Porter Creek.
Halliburton said labyrinth weirs are a popular method for rehabilitation due to the lack of options for viable drainage solutions.
“We don’t have many options left, as we can’t go around because of the population that’s moved in,” Halliburton said. “We can’t go around. The road below (Goforth Road) can’t hold much water.”
The PCCD will foot roughly $454,000 of the $7.95 million price tag due to a state and federal funding agreement. According to a PCCD 2015 newsletter, the federal government is covering 65 percent of the cost, while the Texas State Soil and Water Conservation Board will take 33 percent.
In addition, the PCCD has also received assistance from Hays County, which has closed off Goforth Road at the dam site. Halliburton said the need to close the roads was due to moving material without “worrying about traffic.”
“It was important to be done for the safety of the community,” said Halliburton. “We know it’s frustrating to a lot of folks in the area, but when this project is finished, it’s a project we can be proud of.”
The PCCD is now placing its focus on potentially rehabilitating two more of its dams in Hays County that are labeled as high hazard due to population growth.
Halliburton said the dams, which are also earthen, are located off FM 2001 between Niederwald and Buda. Halliburton said the design stage of the project has been completed, but no construction sums or funding methods have been determined at this time. Halliburton said it will be up to engineers to determine if a labrynth weir model is needed.
Debbie Ingalsbe, Hays County Pct. 1 commissioner, said in an emailed response it was “great to see” there is a completion date for the Site 6 dam, barring any unexpected delays.
“After speaking to resident and business owners, in the area, the completion date can’t come soon enough,” Ingalsbe said. “Businesses have suffered, tremendously, during the dam rehabilitation and closure of Goforth Road, but we all realize this work is vital to the safety of all who live in the area.”