What’s in your water?
Free tool using EPA data. Covers 10,297 water systems serving most Americans.
Get notified when new EPA PFAS data is released.
- 302M+Americans served by tested systems
- 10,297Water systems tested
- 29PFAS compounds tracked
Source: EPA UCMR 5 (2023–2026)
How it works
Enter your zip code
We look up which water system serves your area using EPA data.
See your grade
Every system gets a letter grade (A through F) based on PFAS levels vs federal limits.
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.
- F
Parkersburg, WV
Worst: PFOA at 7.3× the federal limit
Read the report →
- D
Calhoun, GA
Worst: PFOA at 3.9× the federal limit
Read the report →
- D
Hastings, MN
Worst: PFOA at 3.0× the federal limit
Read the report →
- D
Security-Widefield, CO
Worst: PFOS at 2.5× the federal limit
Read the report →
- D
Rhinelander, WI
Worst: PFOA at 1.6× the federal limit
Read the report →
- D
Parchment, MI
Worst: PFOS at 1.4× the federal limit
Read the report →
- D
French Island, WI
Worst: PFOS at 1.2× the federal limit
Read the report →
- D
Newburgh, NY
Worst: PFOA at 1.1× the federal limit
Read the report →
- B
Airway Heights, WA
Worst: PFHxS at Below federal limit
Read the report →
- B
Rockford, MI
Worst: PFBA
Read the report →
Latest investigations
Plain-language reporting on what EPA testing has found in specific communities, and what residents can do about it.
- City Investigation
PFAS in Calhoun, GA: What Water Tests Revealed in Georgia's Carpet Capital
EPA testing of Calhoun's drinking water found PFOA at nearly four times the federal limit and PFOS at more than three times. The contamination traces back to decades of carpet treatment in the Dalton industrial corridor.
April 7, 2026 · 5 min read
- Explainer
EPA PFAS Standards Explained: What the 2024 Drinking Water Limits Mean
In April 2024 the EPA set the first-ever federal drinking water limits on six PFAS compounds. Here's what those limits are, how the Hazard Index works, and what happens to your utility if it exceeds them.
April 7, 2026 · 7 min read
- Guide
How to Filter PFAS From Your Drinking Water: What Actually Works
Three filtration technologies have been tested and certified to remove PFAS from drinking water. This is a brand-neutral guide to what they are, what they cost, and what to look for on the box.
April 7, 2026 · 8 min read
Latest PFAS news
Curated coverage of regulations, lawsuits, and research.
- EPA Action
EPA and HHS say they will target forever chemicals in tap water, but new rules may be years away
EPA and the Department of Health and Human Services announced a joint plan to address PFAS, microplastics, and pharmaceuticals in drinking water. The agency said it would add these pollutants to the next Contaminant Candidate List, but the list is not expected to be signed until November and binding limits could take years after that.
CNN · April 2, 2026
- Local Coverage
Small North Carolina water systems warn they cannot afford PFAS treatment
A new study finds that small water utilities in North Carolina are facing rising costs to comply with PFAS limits, and some say they cannot pay for treatment without raising rates sharply. Operators worry that the 2031 federal deadline is too short for systems that serve a few thousand customers. State lawmakers are weighing whether to help with grants from the 3M settlement funds.
North Carolina Health News · April 2, 2026
- Legal
Saint-Gobain to pay $1.71 million to connect contaminated homes in Londonderry to public water
The New Hampshire attorney general reached an agreement with Saint-Gobain requiring the company to pay $1.71 million toward extending a water main to about 350 homes with PFAS-contaminated wells in Londonderry. The deal is the latest in a long line of settlements tied to PFAS from the company's former Merrimack plant. The town will still carry the long-term cost of maintaining the new water line.
Concord Monitor · March 31, 2026