Chlorine dioxide in U.S. Drinking Water
Health-based violation data for Chlorine dioxide from EPA Safe Drinking Water Information System (SDWIS). Covers all community water systems with violations on record.
Chlorine dioxide has been found in violation of EPA standards in 25 water systems across 10 states, with 120 total health-based violations recorded. The most affected states are Arizona, Louisiana, Texas.
Chlorine dioxide is regulated under the EPA Safe Drinking Water Act, which sets enforceable Maximum Contaminant Levels (MCLs) and associated treatment technique requirements for public water systems. The EPA Safe Drinking Water Information System (SDWIS) tracks every recorded violation nationwide and links it back to the specific public water system (PWSID), violation type, and begin date.
Across the United States, PlainEnviro's joined extract contains 120 health-based violation records carrying Chlorine dioxide (EPA code 1008) across 25 active community water systems in 10 states. Raw record counts are highest in Arizona, Louisiana, Texas, with Arizona accounting for 44 records across 1 system. Health-effect prose is shown only when the official ECHO substance name matches a verified topic; otherwise the portal stays silent rather than inventing guidance.
A health-based violation does not mean residents were necessarily harmed, it means the contaminant exceeded the federal MCL in a compliance sample, triggering notification and remediation requirements. States and utilities maintain primary enforcement responsibility. To check the status of a specific water system, request its most recent Consumer Confidence Report or consult the EPA's Drinking Water Watch portal for the corresponding state.
Violations by State
States ranked by number of health-based violations for Chlorine dioxide.
Most Affected Water Systems
Top 50 water systems by number of Chlorine dioxide health-based violations.
| Water System | State | Violations |
|---|---|---|
| CITY OF YUMA | AZ | 44 |
| CITY OF FRANKLIN WATER SUPPLY | LA | 14 |
| TOWN OF BLANCHARD WATER SYSTEM | LA | 6 |
| JAMESTOWN WATER DEPARTMENT | RI | 6 |
| LACYGNE, CITY OF | KS | 4 |
| MAVERICK COUNTY AIRPORT WATER WORKS | TX | 4 |
| LAKE LIVINGSTON OAKRIDGE NORTH | TX | 4 |
| BENTON-WASHINGTON REGIONAL PWA | AR | 3 |
| TRYON | OK | 3 |
| BEDFORD COUNTY U.D. | TN | 3 |
| COLORADO CITY MD | CO | 2 |
| ELLSWORTH CO RWD 1 | KS | 2 |
| RUSSELL, CITY OF | KS | 2 |
| PARISH UTILITIES OF ASCENSION | LA | 2 |
| CITY OF HAMMOND WATER SYSTEM | LA | 2 |
| CITY OF RIO HONDO | TX | 2 |
| CITY OF CISCO | TX | 2 |
| CITY OF GRAHAM | TX | 2 |
| ITHACA CITY | NY | 1 |
| CITY OF ANAHUAC | TX | 1 |
| EASTLAND COUNTY WATER SUPPLY DISTRICT | TX | 1 |
Frequently Asked Questions
Is Chlorine dioxide in my water?
Chlorine dioxide has been detected in violation of EPA health standards in 25 water systems across 10 states. To check your specific utility, look up your annual Consumer Confidence Report (CCR) - water systems are required to disclose all violations.
How many water systems have Chlorine dioxide violations?
EPA SDWIS records show 25 community water systems with health-based Chlorine dioxide violations, totaling 120 violations. These represent cases where the contaminant exceeded the EPA Maximum Contaminant Level (MCL).
Which states have the most Chlorine dioxide violations?
The states with the most Chlorine dioxide violations are: Arizona (44 violations), Louisiana (24 violations), Texas (16 violations), Kansas (8 violations), Rhode Island (6 violations).
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About This Data
Violation data is from the EPA Safe Drinking Water Information System (SDWIS). Only health-based violations are shown, these include Maximum Contaminant Level (MCL) and Treatment Technique (TT) violations. Monitoring and reporting violations are excluded. Data may not reflect the most current enforcement actions.
Source: U.S. Environmental Protection Agency, SDWIS Federal Reporting Services
Read our methodology - how this data is sourced, computed, and verified.