PlainWater
Contaminants →
EPA SDWIS Dense per-system load

Chlorite in Drinking Water

11.6 violations per affected system (3,255 across 280) - dense load (> 5.8 violations per affected system).

Browse all SDWIS contaminants →

EPA contaminant code: 1009

Total Violations
3,255
Systems Affected
280
Health-Based %
16.1%
Violations / System
11.6

Chlorite standing, mid-volume SDWIS third

Chlorite lands in the middle third by violation volume (3,255), large enough for peer comparisons but not one of the handful of analytes that dominate the fleet-wide SDWIS ledger. Load is concentrated: 11.6 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 16.1% - a material slice of the record is exposure-relevant, with the rest monitoring or reporting. Among 157 indexable contaminants, this page is #93 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

Gross Beta Particle Activity (3,274) Stage 2 Disinfectants and Disinfection Byproducts Rule (3,102) COLIPHAGE (2,523) Chloramine (2,449)

Nearest by systems affected

Cryptosporidium (202 systems) Coliform (Pre-TCR) (174 systems) Bromate (140 systems) 38-STRONTIUM-90 (138 systems)

Chlorite: mixed health vs monitoring split

16.1% health-based · 83.9% monitoring/reporting across 3,255 records.

Health-based (16.1%) Monitoring/Reporting (83.9%)

Most Affected Water Systems

System State Violations Population
Mount Carmel IL 144 7,015
Lake Livingston Oakridge North TX 124 3,284
Perry Water & Light Dept OK 104 5,230
Frederick Living PA 98 640
Excela Westmoreland Hospital PA 79 1,500
City of Yuma AZ 68 103,264
Marworth Rehab Center PA 63 178
City of Rio Hondo TX 54 2,640
M & M WSC TX 44 3,208
Fairfield IL 42 6,202
Greenwood Waterworks AR 36 9,905
Colorado City MD CO 36 2,755
Parish Utilities of Ascension LA 36 9,732
Jbsa - Sam Houston TX 36 37,563
Maverick County Airport Water Works TX 35 1,700
Climax Molybdenum Co Henderson Mill CO 34 165
Central Texas WSC TX 34 0
Pueblo West MD CO 33 30,000
Snyder Public Works Authority OK 32 1,509
Lake Durango WA CO 30 1,577
Belle Vernon Boro Muni Auth PA 30 6,000
Woonsocket Water Division RI 29 45,828
Maverick County Airport Water Works TX 29 1,700
Nevada State Veterans Home Boulder City NV 28 708
Blackwell Municipal Authority OK 28 7,668
Eastland County Water Supply District TX 28 0
Lake Livingston Pineshadows East TX 28 5,675
Pagosa Area WSD CO 26 11,069
Lacygne, City Of KS 23 1,119
Public Wholesale WSD 19 KS 22 1

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.