What a drinking water violation notice means

Why water systems send these notices

Every public water system, from a city utility to a campground well, must give public notice when it violates a national primary drinking water regulation. Under 40 CFR 141.201 that covers four kinds of violation:

• exceeding a maximum contaminant level (MCL) or a maximum residual disinfectant level (MRDL)
• failing to follow a required treatment technique
• failing to carry out required water quality monitoring
• failing to follow a required testing procedure

Notices are also required for some situations that are not violations, such as a waterborne disease outbreak or emergency, an exceedance of the lead action level, or the availability of results from EPA's unregulated contaminant monitoring. Because notice is required even for paperwork-type lapses, receiving one does not by itself mean anything was found in your water. The notice will say which kind of problem it is.

The three tiers and their deadlines

Federal rules sort every notice into one of three tiers by how serious the potential health effects are.

Tier 1 covers violations and situations with significant potential for serious health effects from short-term exposure. Examples in the rule include an E. coli MCL violation, a nitrate or nitrite MCL violation, a waterborne disease outbreak or other waterborne emergency, and an exceedance of the lead action level. The system must notify people as soon as practical and no later than 24 hours after it learns of the problem, using broadcast media, posting throughout the area served, hand delivery, or another method the state approves. It must also consult the state within 24 hours.

Tier 2 covers all other MCL, MRDL and treatment technique violations, plus monitoring violations the state decides warrant it. Notice is due as soon as practical and no later than 30 days after the system learns of the violation, and it must be repeated every three months while the violation continues, unless the state sets a different frequency (never less than once a year). Community systems typically send it by mail or direct delivery to each customer.

Tier 3 covers most monitoring and testing-procedure violations, operation under a variance or exemption, and a few other situations. Notice is due within one year and is repeated annually while the situation continues. A community water system may deliver a Tier 3 notice inside its annual Consumer Confidence Report.

If your notice says the system did not monitor

Many notices people receive are monitoring violations. These use standard federal wording: the system says it is required to monitor your drinking water for specific contaminants on a regular basis, that during a stated period it did not monitor or test (or did not complete all monitoring or testing) for named contaminants, and "therefore cannot be sure of the quality of your drinking water during that time."

That wording describes a gap in testing or reporting, not a test result. It means the required sample was missed, taken late, or not reported on time. It is still a real compliance failure, because regular monitoring is how problems are caught, and the notice should say what the system is doing to get back on schedule.

What every notice must tell you

Under 40 CFR 141.205, a notice for a violation must include:

1. A description of the violation or situation, including the contaminant and, where applicable, the level found.
2. When it occurred.
3. Any potential adverse health effects, using EPA's standard health effects language.
4. The population at risk, including people who may be especially vulnerable.
5. Whether you should use an alternative water supply.
6. What actions you should take, including when to seek medical help, if known.
7. What the system is doing to correct the problem.
8. When the system expects to return to compliance.
9. The name, business address and phone number of a contact at the water system.
10. Where applicable, a request to share the notice with others who drink the water, such as people in apartments, nursing homes, schools and businesses.

Items 5 and 6 are the ones to read first. Because every notice must state whether an alternative water supply should be used, a notice that does not ask you to change how you use your water should make that clear.

Boil water and do-not-drink advisories

Urgent problems are often communicated as a drinking water advisory. CDC describes three kinds: a boil water advisory, a do not drink advisory, and the most restrictive, a do not use advisory. Follow the specific instructions from your utility or health department. For boil water advisories, CDC's general guidance is to bring water to a full rolling boil for 1 minute, or 3 minutes at elevations above 6,500 feet. CDC also notes that boiling does not make water with harmful chemicals or toxins safe, which is why a do-not-drink advisory points to bottled water instead.

Checking a system's violation history

Violations are reported to EPA and published in its SDWA data, which AquaCensus shows on each water system page. EPA ECHO defines a health-based violation as an exceedance of an MCL or MRDL, or a treatment technique violation. A monitoring and reporting violation is a failure to monitor or to submit results on time. Each violation also carries a status:

• Resolved: at least one resolving action is on record, meaning the system returned to compliance, the rule no longer applies, or no further action was needed.
• Archived: not resolved, but more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
• Addressed: not resolved or archived, and covered by formal enforcement.
• Unaddressed: not resolved or archived, and not yet covered by formal enforcement.

Across the 5.39 million violation records in AquaCensus, about 564,000 (roughly 10%) are flagged health-based. About 4.09 million are resolved, 1.23 million archived, 9,635 addressed and 56,059 unaddressed. EPA notes that violations reach its public data about four to five months after they occur and that state-reported data can be incomplete, so a recent problem may not appear yet.

Who to contact

Start with the contact named on the notice, since the water system knows the details and the timeline. Each AquaCensus system page names the state drinking water program that oversees the system, which can confirm compliance status. EPA takes general drinking water questions through its online contact form. For questions about your own health, or that of someone who may be especially vulnerable, talk to a health care provider.