Total Trihalomethanes (TTHM)
Unresolved Total Trihalomethanes Rule violation cited in 2021 (total trihalomethanes (tthm)).
PWSID NM3522912 · GroundwaterMunicipal
118 people served. No health-based SDWIS violations recorded in the past 5 years. 13 remain unresolved. Last cited 2 years ago.
Unresolved Total Trihalomethanes Rule violation cited in 2021 (total trihalomethanes (tthm)).
Unresolved Total Trihalomethanes Rule violation cited in 2021 (total trihalomethanes (tthm)).
Unresolved Total Trihalomethanes Rule violation cited in 2021 (total trihalomethanes (tthm)).
Unresolved Total Trihalomethanes Rule violation cited in 2021 (haloacetic acids (haa5)).
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
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled
OTHER; returned to compliance
Monitoring failure; returned to compliance
Monitoring failure; returned to compliance
Monitoring failure; returned to compliance
Monitoring failure; returned to compliance
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
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
OTHER; returned to compliance
OTHER
OTHER; returned to compliance
OTHER; returned to compliance
OTHER; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled
Hidalgo County, New Mexico (utility's served county per SDWIS GEOGRAPHIC_AREA — city-level not yet matched): a service population of 4,160. Local disparity score for pm2.5 (fine particulate) sits well below the reference (2). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 2 | well below the reference |
| Ozone | 181 | well above the reference burden |
| Nitrogen dioxide (NO₂) | 77 | below the reference |
| Diesel particulate | 41 | well below the reference |
| Toxic releases (RSEI) | 8 | well below the reference |
| Traffic proximity | 26 | well below the reference |
| Lead-paint risk (pre-1960 housing) | 105 | near the reference |
| Superfund site proximity | 0 | well below the reference |
| RMP-facility proximity | 0 | well below the reference |
| Hazardous-waste site proximity | 0 | well below the reference |
| Underground storage tanks | 110 | moderately above the reference |
| NPDES wastewater proximity | 30 | well below the reference |
| Drinking-water non-compliance | 200 | well 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.