City, Greenbelt address water quality issue

The City of Clarendon is working with Greenbelt Water Authority to address a water quality issue found by the Texas Commission on Environmental Quality (TCEQ) recently.

Earlier this month, the city gave public notice that the TCEQ had determined the level of trihalomethanes (THMS) in Clarendon’s drinking water had exceeded the maximum containment level of 0.080 milligrams per liter (mg/L), and the city’s level at sampling was 0.114 mg/L. 

The state says people do not need to use an alternative water supply but that exposure to high levels of THMS over many years may cause health problems.

Greenbelt General Manager Bobbie Kidd said THMS is a byproduct of disinfecting water which contains organic matter and said it is not an easy problem to fix.

“It’s a complex problem,” Kidd said. “Unfortunately, with the lake as low as it is, we have a whole lot of organic matter in the water.”

According to the state, THMS are a group of volatile organic compounds that are formed when chlorine, added to the water during the treatment process for disinfection, reacts with naturally occurring organic matter in the water.

Kidd said adding ammonia to the treatment process can help with the THMS level but said Greenbelt had cut back on ammonia to address problems other Greenbelt member cities were having further down the line.

“We kind of hurt ourselves here when we did that,” he said. “We’re going to have to start putting more ammonia in there.”

But Kidd said it won’t be a quick or easy fix. In addition to the low lake levels increasing the organic matter, the high temperatures this summer will also make the problem more difficult to solve.

Interim City Administrator Floyd Hartman says the problem is a challenge that will be ongoing but said the city and Greenbelt are working together to address the matter.

“They [Greenbelt] are going to address this in a positive way with their treatment process, and we’re going to do additional sampling,” Hartman said. 

The city also says compliance with the state is based on a three-test average, so future samples will be averaged against the current samples.

“It’s going to be a process getting into compliance,” Hartman said.