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EPA SDWIS High-volume analyte Dense per-system load

Interim Enhanced Surface Water Treatment Rule in Drinking Water

24.7 violations per affected system (72,147 across 2,920) - dense load (> 5.8 violations per affected system).

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EPA contaminant code: 0300

Total Violations
72,147
Systems Affected
2,920
Health-Based %
40%
Violations / System
24.7

Interim Enhanced Surface Water Treatment Rule standing, high-volume SDWIS third

Interim Enhanced Surface Water Treatment Rule sits in the upper third of this extract by raw violation count (72,147), 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: 24.7 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 40% - a material slice of the record is exposure-relevant, with the rest monitoring or reporting. Among 157 indexable contaminants, this page is #42 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

Nitrite (72,418) Vinyl chloride (76,766) Fluoride (78,347) Xylenes, Total (79,013)

Nearest by systems affected

Asbestos (2,694 systems) Aldicarb sulfoxide (3,220 systems) Aldicarb sulfone (3,221 systems) Aldicarb (3,231 systems)

Interim Enhanced Surface Water Treatment Rule: mixed health vs monitoring split

40% health-based · 60.0% monitoring/reporting across 72,147 records.

Health-based (40%) Monitoring/Reporting (60.0%)

Most Affected Water Systems

System State Violations Population
North Havre County Water Dist MT 545 90
City of Toyah TX 492 89
Cassie Water System TX 475 106
Mohawk Valley School District AZ 444 171
Adair Co RWD #5 OK 393 675
Delaware OK 365 456
Fruitland Domestic WC CO 351 335
City of Nome TX 319 825
Specht Store TX 311 170
South Mountain Restoration Ctr PA 306 950
Wewoka Public Works Authority OK 302 3,450
Otoe-Missouria Tribe OK 297 250
Gypsy River Resort TX 290 87
Kongiganak Water System AK 285 547
Locust Grove OK 284 1,600
Metropolitano PR 275 1,077,332
Sardis Lake Water Authority OK 259 307
Pawnee OK 253 2,230
Auth of Boro of Charleroi PA 234 27,000
Clearwater Water Dist ID 232 80
Lamont OK 232 417
Cedro Arriba PR 232 5,482
Seven Hills Ranch TX 232 801
Pine River Mdca NM 228 44
Selawik Safewater Facility AK 220 846
Trollers Cove Water Assn OR 219 32
Alakanuk Water System AK 217 570
City of Rose City TX 217 664
Pinecrest Village MHP PA 215 195
Pittsburg Co. RWD #14 OK 210 1,680

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.