TTHM (Total Trihalomethanes) violations in Texas
514 active public water systems in Texas had a TTHM (Total Trihalomethanes) violation in the past three years, 157 of them in the latest quarter of EPA's data. What TTHM (Total Trihalomethanes) is and why it matters.
Systems with a TTHM (Total Trihalomethanes) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Ocean Mobile Home Park Chambers County |
347 | 5 | 1 | |
|
Copano Heights Water Aransas County |
330 | 2 | 0 | |
|
National Oilwell Gray County |
325 | 5 | 1 | |
|
Parkway Water System San Augustine County |
322 | 4 | 0 | |
|
Baker Hughes Emmott RD Plant Harris County |
319 | 8 | 0 | |
|
Mountain Crest Water Hays County |
309 | 1 | 0 | |
|
Amberwood Water System Randall County |
300 | 7 | 2 | |
|
Llano Grande Lake Park West Hidalgo County |
300 | 4 | 2 | |
|
Cedar Bayou Park Harris County |
294 | 4 | 2 | |
|
Blue Ridge Water System Parker County |
285 | 7 | 1 | |
|
Harmony Water System Parker County |
285 | 8 | 0 | |
|
Moores Water System McLennan County |
285 | 7 | 4 | |
|
Green Rich Shores and Sterling Island SU Walker County |
275 | 2 | 0 | |
|
Cotton Bayou Park Chambers County |
270 | 5 | 1 | |
|
Garden Acres Subdivision Gregg County |
255 | 7 | 2 | |
|
Summit Ridge Medina County |
252 | 2 | 0 | |
|
Ineos Green Lake Plant Calhoun County |
250 | 2 | 0 | |
|
Martin Lake Steam Electric Station Rusk County |
250 | 6 | 0 | |
|
Minerva WSC Milam County |
250 | 5 | 0 | |
|
Rockwell Acres Water System Randall County |
250 | 12 | 4 | |
|
Theall Business Park Harris County |
250 | 3 | 0 | |
|
Holiday Harbor Marion County |
249 | 3 | 2 | |
|
Wilco Water Brazoria County |
243 | 2 | 0 | |
|
Anadarko Carrizo Springs Facility Dimmit County |
238 | 5 | 0 | |
|
City of Moran Shackelford County |
235 | 6 | 0 | |
|
City of Goodlow Navarro County |
234 | 6 | 0 | |
|
River Oaks Subdivision Chambers County |
234 | 3 | 0 | |
|
Houston V & M Star Harris County |
230 | 4 | 1 | |
|
Sudduth Water System Falls County |
230 | 7 | 4 | |
|
Cedarview Estates Henderson County |
228 | 5 | 1 | |
|
Anderson Water System Grimes County |
226 | 10 | 5 | |
|
Deer Run and White Rock City Marina Trinity County |
226 | 8 | 4 | |
|
Comanche County WSC Sipe Springs Comanche County |
219 | 7 | 4 | |
|
Loma Linda Water Supply Jim Wells County |
216 | 12 | 3 | |
|
South Garza WSC Garza County |
216 | 3 | 2 | |
|
Port Alto HOA District 1 Calhoun County |
213 | 2 | 0 | |
|
Clay WSC Burleson County |
210 | 5 | 1 | |
|
Firstday Foundation Harris County |
200 | 1 | 0 | |
|
Katy Plaza Harris County |
200 | 5 | 1 | |
|
Flowserve US Harris County |
200 | 1 | 0 | |
|
Richards Water System Grimes County |
200 | 11 | 4 | |
|
Ten Plaza West Harris County |
200 | 3 | 2 | |
|
The District on 46 Comal County |
200 | 3 | 0 | |
|
Pci Nitrogen Pasadena Harris County |
198 | 3 | 0 | |
|
Target Hospitality West EL Capitan Lodge Culberson County |
198 | 4 | 0 | |
|
Warren Road Subdivision Water Supply Midland County |
195 | 13 | 6 | |
|
Acorn Village Mobile Home Park Harris County |
192 | 6 | 2 | |
|
Rolling Hills Water Supply McLennan County |
186 | 12 | 3 | |
|
Derby Ing Frio County |
174 | 9 | 2 | |
|
City of Midway Madison County |
173 | 1 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved TTHM (Total Trihalomethanes), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not TTHM (Total Trihalomethanes) alone.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Texas records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.