Total Trihalomethanes (TTHM)
Unresolved Total Trihalomethanes Rule violation cited in 2025 (total trihalomethanes (tthm)).
PWSID TX0730002 · Surface waterMunicipal
5,967 people served. 31 health-based SDWIS violations recorded in the past 5 years. 25 remain unresolved. Last cited 1 year ago.
Unresolved Total Trihalomethanes Rule violation cited in 2025 (total trihalomethanes (tthm)).
Unresolved Total Trihalomethanes Rule violation cited in 2025 (haloacetic acids (haa5)).
Unresolved Long Term 1 Enhanced SWTR violation cited in 2025 (contaminant 0300).
Unresolved Volatile Organic Chemical Rule violation cited in 2025 (contaminant 7500).
Health-based violations exceed an MCL or treatment-technique standard. Monitoring violations are reporting failures with no measured exceedance — they tell you the system isn't fully transparent, not that the water is unsafe today.
OTHER; returned to compliance
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Failure to monitor as scheduled
OTHER
OTHER
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
OTHER
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
OTHER
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded; returned to compliance
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Maximum contaminant level exceeded
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
Maximum contaminant level exceeded; returned to compliance
Treatment technique violation; returned to compliance
Treatment technique violation; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Maximum contaminant level exceeded; returned to compliance
Treatment technique violation; returned to compliance
Maximum contaminant level exceeded; returned to compliance
OTHER; returned to compliance
Maximum contaminant level exceeded; returned to compliance
Treatment technique violation; returned to compliance
Treatment technique violation; returned to compliance
Maximum contaminant level exceeded; returned to compliance
Marlin, Texas (Census place; block-group disparity scores aggregated by centroid containment): a service population of 5,478. Local disparity score for pm2.5 (fine particulate) sits moderately above the reference (144). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 144 | moderately above the reference |
| Ozone | 135 | moderately above the reference |
| Nitrogen dioxide (NO₂) | 175 | well above the reference burden |
| Diesel particulate | 105 | near the reference |
| Toxic releases (RSEI) | 102 | near the reference |
| Traffic proximity | 56 | below the reference |
| Lead-paint risk (pre-1960 housing) | 220 | severely above the reference burden |
| Superfund site proximity | 0 | well below the reference |
| RMP-facility proximity | 149 | moderately above the reference |
| Hazardous-waste site proximity | 0 | well below the reference |
| Underground storage tanks | 187 | well above the reference burden |
| NPDES wastewater proximity | 90 | near the reference |
| Drinking-water non-compliance | 255 | severely above the reference burden |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Source. EPA Safe Drinking Water Information System · retrieved 2026-05-07. Reporting period 2020-01-01 → 2026-05-07.
What this is not. SDWIS records compliance against federal MCLs — not a direct readout of tap-water concentrations. Active health-based violations are not the same as a current crisis; we link to the EPA record so you can verify return-to-compliance status before forming a conclusion.