EPA "Serious Violator" Water Systems, Explained (2026 List)

A “serious violator” is a public water system that EPA’s scoring system flags for having a combination of unresolved Safe Drinking Water Act violations. EPA gives each unresolved violation 1, 5 or 10 points depending on how severe it is, and a system with a total of at least 11 points is labeled a serious violator. The label means a system has compliance problems that have not been fixed or formally addressed. It does not by itself mean the water is unsafe to drink.

Of the 1,000 large water systems on TapWaterSafety.org with an EPA record, 34 carried the serious violator label when we checked on October 7, 2026. Together they serve about 4.4 million people. Twenty-seven of the 34 are in Florida. The full list is below.

What “serious violator” means

EPA’s Enforcement and Compliance History Online (ECHO) website publishes a serious violator flag for every public water system. According to EPA’s ECHO FAQ on drinking water:

• Scoring. EPA assigns one, five or ten points to each violation to reflect its severity. Health-based violations are weighted more heavily than monitoring or paperwork violations.
• Threshold. Systems with an aggregate score of at least 11 points, based on unresolved, multiple or continuing violations, are called serious violators.
• “Unresolved” is the key word. A violation stops counting once the system returns to compliance or once the state (or EPA) takes a formal enforcement action to address it. EPA defines “continuing” as a violation that has not been reported as corrected or as addressed by a formal enforcement action.
• Expected timeline. EPA expects a system with serious violations to either return to compliance or be addressed by a formal enforcement action within six months.
• Snapshot in time. The list is updated quarterly. EPA notes that violations may have been corrected or addressed since the last update.

The scoring comes from EPA’s Enforcement Targeting Tool, which supports the agency’s 2009 drinking water Enforcement Response Policy. That policy focuses enforcement on systems with health-based violations and on systems with a history of violations across multiple rules.

Serious violator vs. “significant noncompliance”

You may also see the term significant noncompliance (SNC) on ECHO. That label is used for other programs, such as Clean Water Act discharge permits and hazardous waste facilities. For drinking water systems, ECHO’s comparable label is “serious violator.” The two terms come from different programs and have different rules, so they are not interchangeable.

Who enforces it

States run most drinking water enforcement. EPA says front-line enforcement responsibility rests with states, territories and the Navajo Nation, while EPA keeps enforcement authority in those states. Wyoming, the District of Columbia and most tribal lands are exceptions where EPA has front-line responsibility. Because a formal enforcement action removes violations from the score, how a state handles enforcement can affect whether a system stays on the list.

What the label does and does not tell you

It does tell you that a system has several unresolved violations, or at least one severe one combined with others, and that no formal enforcement action had resolved them as of EPA’s last update.

It does not tell you:

• That the water is contaminated. Most of the serious violators in our data have only monitoring, reporting or notice violations. Missing a test or filing a late report adds points even when no contaminant problem was found.
• That other systems are fine. A system with a serious health-based violation can drop off the list once a formal enforcement order is in place, even if the underlying problem is still being fixed. In our data, 81 systems have a health-based violation listed but are not labeled serious violators. New York City, Boston and Portland are among them.
• Current status. ECHO data lags. EPA says reported violations appear in ECHO about 4 to 5 months after they occur.

The 34 serious violators in our data

Source: EPA ECHO compliance records, checked October 7, 2026; last 12 quarters. This covers only the 1,000 larger systems graded on our site (each serving over 50,000 people). Many smaller systems nationwide also carry the label and are not listed here.

“Health-based” shows whether the EPA record lists any maximum contaminant level (MCL) or treatment technique (TT) violation. “Other violation types” covers monitoring, reporting, public notice and Consumer Confidence Report (CCR) violations.

Patterns in the list

• Most are about testing and reporting. 25 of the 34 serious violators have no health-based violation in their EPA record. Their points come from monitoring, reporting, public notice and CCR violations.
• Nine have a health-based violation listed. These are Trenton, Shreveport, Syracuse, Jackson, Pembroke Pines, Altoona, Monroe, Lauderhill and South Blount.
• Long-running issues. 23 of the 34 were in violation in all 12 of the last 12 quarters.
• Florida stands out. 27 of the 34 are Florida systems. All 27 have a violation listed under the Revised Total Coliform Rule, 21 under the Stage 2 disinfection byproducts rule, 20 under the Consumer Confidence Rule, and 15 each under the Nitrate Rule and the Lead and Copper Rule. Only two of the 27 (Pembroke Pines and Lauderhill) have a health-based violation listed; the rest are monitoring, reporting or notice violations. Our data can’t tell you why so many Florida systems are flagged. Because states handle most drinking water enforcement and data reporting, differences in how violations are recorded, resolved and closed out can affect which systems appear on the list. If you live in one of these areas, the best step is to read your system’s EPA report and ask the utility directly.

For a broader view of long-running violations, including health-based ones at systems that are not serious violators, see US water systems with the most EPA violations. For state totals, see states ranked by drinking water violations.

What to do if your system is a serious violator

1. Open the EPA report. Each utility page on our site links to its ECHO Detailed Facility Report, which lists every violation, the rule involved, and whether it is open or closed. You can find your system on our search page.
2. Check the violation type. A health-based violation (MCL, MRDL or treatment technique) matters more for your health than a missed sample or late report.
3. Read your Consumer Confidence Report and any public notices your utility has sent. Utilities report violations there.
4. Ask your utility whether the violations have been corrected and whether a formal enforcement action is in place. Your state drinking water program can also confirm current status.
5. If you have a specific concern, such as lead or disinfection byproducts, a filter certified for that contaminant can reduce your exposure while issues are resolved. Our guide to how to read your water quality report can help you figure out what applies to you.

Note: a utility may have resolved issues or been removed from the serious violator list since October 7, 2026. Check the utility’s EPA ECHO report or its latest Consumer Confidence Report for current status.

Sources

• EPA ECHO: Safe Drinking Water Act Resources and FAQs
• EPA ECHO: Frequently Asked Questions
• EPA: Drinking Water Enforcement Response Policy (2009)
• Virginia Department of Health: EPA List of Serious Violators (Enforcement Targeting)
• EPA news release: EPA releases searchable website for drinking water violations (2011)