2023 · Toxaphene · Nitrate/Nitrite
Failure to monitor as scheduled; returned to compliance
PWSID MD0100030 · Surface waterMunicipal
74,911 people served. No health-based SDWIS violations recorded in the past 5 years. Last cited 3 years ago.
No SDWIS health-based or unresolved violations on the record. Contaminant detail and equity context below.
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.
Failure to monitor as scheduled; 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
Failure to monitor as scheduled; 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
Failure to monitor as scheduled; 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
Frederick, Maryland (Census place; block-group disparity scores aggregated by centroid containment): a service population of 78,390. Local disparity score for pm2.5 (fine particulate) sits well below the reference (27). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 27 | well below the reference |
| Ozone | 78 | below the reference |
| Nitrogen dioxide (NO₂) | 86 | below the reference |
| Diesel particulate | 85 | below the reference |
| Toxic releases (RSEI) | 15 | well below the reference |
| Traffic proximity | 70 | below the reference |
| Lead-paint risk (pre-1960 housing) | 37 | well below the reference |
| Superfund site proximity | 102 | near the reference |
| RMP-facility proximity | 92 | near the reference |
| Hazardous-waste site proximity | 95 | near the reference |
| Underground storage tanks | 75 | below the reference |
| NPDES wastewater proximity | 121 | moderately above the reference |
| Drinking-water non-compliance | 0 | well below the reference |
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 2023-01-01 → 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.