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CheckYourWater

What’s in your water?

Free tool using EPA data. Covers 10,297 water systems serving most Americans.

  • 302M+Americans served by tested systems
  • 10,297Water systems tested
  • 29PFAS compounds tracked

Source: EPA UCMR 5 (2023–2026)

How it works

  1. Enter your zip code

    We look up which water system serves your area using EPA data.

  2. See your grade

    Every system gets a letter grade (A through F) based on PFAS levels vs federal limits.

  3. Know what to do

    Get plain-language explanations and specific action steps based on what's in your water.

What are PFAS?

PFAS (per- and polyfluoroalkyl substances) are synthetic chemicals used since the 1950s in products like non-stick cookware, food packaging, stain-resistant fabrics, and firefighting foam. They’re called “forever chemicals” because they don’t break down in the environment or in the human body. Research has linked PFAS exposure to health effects including certain cancers, thyroid disease, immune system effects, and reproductive issues. In 2024, the EPA set the first-ever federal limits on PFAS in drinking water.

Learn more →

Cities most affected by PFAS contamination

Communities where EPA testing has found the highest levels of PFAS in drinking water.

See all 20 monitored cities →