San Angelo Drinking Water Exceeds Federal Safety Limit for Byproducts

SAN ANGELO, TX - San Angelo’s drinking water recently exceeded federal safety limits for disinfection byproducts, prompting city officials to increase monitoring and notify residents of potential long-term health risks.

The Texas Commission on Environmental Quality (TCEQ) found that levels of trihalomethanes (TTHMs) in the city’s water supply surpassed the Environmental Protection Agency’s maximum contaminant level of 0.080 milligrams per liter, with recent tests showing levels between 0.081 and 0.083 milligrams per liter.

Although no immediate health risk is posed, and no action needs to be taken by citizens, prolonged exposure to TTHMs above this threshold can increase risks of cancer and liver, kidney, and nervous system issues. City officials said that it is not necessary to use an alternative water supply, the City of San Angelo is monitoring disinfection byproduct levels. 

The elevated TTHM levels resulted from San Angelo relying solely on treated surface water during an expansion of the city’s groundwater facility, which is nearly complete.

"Elevated trihalomethane levels occurred as a result of using solely surface water in our treated water supply," the city stated. "We normally blend treated surface water with treated groundwater, which is less likely to form high levels of trihalomethanes." 

Once the facility resumes, blended groundwater is expected to help reduce TTHM formation. In the interim, the city is performing hydrant flushes and closely monitoring water quality.

Residents with questions may contact John Kaufman at 325-657-4209.