EPA data for 198 US cities
What's really in your tap water and your air?
Chlorine or chloramine, hardness, lead, PFAS and EPA violations for your utility, plus your county's radon zone. In plain English, with what to do about it whether you rent or own.
102
cities on chloramine
which most shower filters can't remove
Read the guide
81
cities with hard water
where only a softener stops scale
Read the guide
69
cities with a PFAS result over a 2024 limit
in EPA's 2023-25 sampling
Read the guide
35
cities in radon zone 1 counties
EPA's highest-risk tier
Read the guide
01
Your utility's own record
We match each city to the water system that serves it in EPA's database, then pull its disinfectant, lead sampling, violations and PFAS results.
02
Plus the air in your basement
Radon is the second leading cause of lung cancer. We show EPA's radon zone for every county, and when testing is worth it.
03
Advice that fits your lease
Renters get no-plumbing options. Owners get whole-home fixes and free installer quotes where it matters: softeners and radon mitigation.
Largest cities
All 198 citiesExplore by state
Share of each state's counties in EPA radon zone 1, where the predicted average indoor level is above 4 pCi/L.