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EPA SDWIS High-volume analyte Dense per-system load

Coliform (TCR) in Drinking Water

18.7 violations per affected system (1,839,196 across 98,293) - dense load (> 5.8 violations per affected system).

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EPA contaminant code: 3100

Total Violations
1,839,196
Systems Affected
98,293
Health-Based %
30.1%
Violations / System
18.7

Coliform (TCR) standing, high-volume SDWIS third

Coliform (TCR) sits in the upper third of this extract by raw violation count (1,839,196), so the national record is thick enough that system-level lists below are a sample of a much larger compliance trail rather than a near-complete inventory. Load is concentrated: 18.7 violations per affected system (dense load (> 5.8 violations per affected system)), which usually means repeat findings on the same PWSIDs rather than one-off detections spread thin. Health-based share is 30.1% - a material slice of the record is exposure-relevant, with the rest monitoring or reporting. Among 157 indexable contaminants, this page is #1 by violation volume. Utilities listed below are ranked by cumulative violation count for this analyte; pair that with population served to gauge household exposure scale.

Nationwide similar contaminants

Nearest by violation volume

Revised Total Coliform Rule (710,085) Nitrate (490,545) TTHM (327,560) Public Notice (326,526)

Nearest by systems affected

Lead and Copper Rule (41,280 systems) Consumer Confidence Rule (29,061 systems) Total Haloacetic Acids (HAA5) (18,140 systems) E. COLI (17,344 systems)

Coliform (TCR): mixed health vs monitoring split

30.1% health-based · 69.9% monitoring/reporting across 1,839,196 records.

Health-based (30.1%) Monitoring/Reporting (69.9%)

Most Affected Water Systems

System State Violations Population
Rivershore Community LLC MT 998 90
The Missing Well MO 991 173
Hidden Valley MHP LLC MO 943 60
Waterhole Saloon Reedpoint MT 922 25
Coal Mountain Water WV 901 80
Veguita PR 831 90
Clear Creek RV Park MO 780 100
Cubuy-Marines PR 766 150
Villa Blanca PR 764 306
Sist. Rural Graulao PR 716 64
Acued. la Grama PR 701 60
Sector Laguna PR 679 27
Mogote PR 676 140
Hacienda Rullan PR 673 340
Sierrita PR 662 268
Lucas Lugo PR 661 40
Town of Charmwood MO 655 28
Com. Saltos Cabra PR 650 500
Palomas II PR 648 47
Hacienda Planell PR 637 25
Asoc. Pro Bienestar Magueyes PR 636 140
Lumberton Mdwca NM 634 223
Servicio de Agua PR 633 300
Starlight Village MO 631 65
La Cascada Milagrosa PR 627 240
Hiawatha Water WV 613 63
Pandura PR 604 240
Alturas de Collores PR 603 300
Key Road Subdivision Water System TX 602 54
Veguitas Gripinas PR 599 130

Context: understanding water quality data · is my water safe?

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the EPA Safe Drinking Water Information System (SDWIS). Consult a qualified professional before making decisions based on this data.

Read our methodology - how this data is sourced, computed, and verified.

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.