The Texas Commission on Environmental Quality (TCEQ) has notified the Twin Buttes Water System public water system that the drinking water being supplied to customers had exceeded the Maximum Contaminant Level (MCL) for total trihalomethanes. The U.S. Environmental Protection Agency (U.S. EPA) has established the MCL for total trihalomethanes to be 0.080 milligrams per liter (mg/L) based on a locational running annual average (LRAA), and has determined that it is a health concern at levels above the MCL. Analysis of drinking water in your community for total trihalomethanes indicates a compliance value in quarter four 2025 of 99.6 mg/L for DBP2-1.
Trihalomethanes 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.
Some people who drink water containing trihalomethanes in excess of the MCL over many years may experience problems with their liver, kidney, or central nervous systems, and may have an increased risk of getting cancer.
You do not need to use an alternative water supply. However, if you have health concerns, you may want to talk to your doctor to get more information about how this may affect you.
We are taking the following actions to address this issue:
Monitoring water disinfection, water usage, coordinating with the City of San Angelo on water purchased and necessary treatment changes.
