What Is the EPA? Who Sets the Rules for Your Tap Water

If you’re on city water, the EPA is the reason your utility tests its water, has to stay under legal limits and sends you a yearly report. If you’re on a private well, its rules don’t reach your water, and testing is up to you.

What does the EPA regulate in drinking water?

Under the Safe Drinking Water Act, passed in 1974 and amended in 1986 and 1996, the EPA sets national health-based standards for public water systems, according to its overview of the law. For each contaminant it decides to regulate, it first sets a health goal, then an enforceable limit as close to that goal as feasible, or a required treatment process when a numeric limit isn’t practical, as it explains in how it regulates contaminants. The full list is in its National Primary Drinking Water Regulations. It also publishes secondary standards for taste, odor and color, which it recommends but doesn’t enforce.

The 1996 amendments added your right to know: every community water system must send customers a yearly report on its water. Our guide to reading your water quality report walks through it.

Does the EPA regulate private wells?

No. The law doesn’t cover private wells serving fewer than 25 people, per the EPA’s plain-language summary of the act. Our well water testing guide covers what to test for.

Who enforces EPA drinking water rules?

Mostly your state. States can apply for “primacy”, the authority to run the program, if they adopt standards at least as strict as the EPA’s. They make sure water systems test, inspect them and take action when standards aren’t met. Some states set stricter limits than the EPA, so check your state’s rules too. If a system breaks a standard, it has to tell its customers.

Which EPA drinking water rules are changing?

Two that matter at home, as of October 10, 2026:

• PFAS. The April 2024 rule set the first national limits for six PFAS, with compliance due in 2029. In May 2026 the EPA proposed keeping the PFOA and PFOS limits, letting systems ask for more time (to 2031), and removing the other four limits. Those are proposals, not final, so the 2024 rule still applies. Our PFAS guide and news story track where they stand.
• Lead. The Lead and Copper Rule Improvements, a final rule published October 30, 2024, lower the lead action level from 15 to 10 ppb and require lead pipe replacement within 10 years, with most requirements starting November 1, 2027. See our lead guide.