Free EPA data for 37,734 ZIP codes
Know what's in
your water
Search your ZIP code to see EPA violations, contaminant levels, and personalized filter recommendations.
37,734
ZIP Codes Covered
711,911
Violations (5-Year)
413,916
Water Systems
50
States + DC
Water Quality Across America
EPA violation hotspots by ZIP code. Click to explore an area.
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How It Works
Three steps to understanding your local water quality.
Enter Your ZIP Code
Type in your 5-digit ZIP code to look up the public water systems serving your area.
See Violations
Review EPA-reported violations including contaminant types, measured levels, and resolution status.
Get Recommendations
Receive personalized water filter recommendations based on the specific contaminants found in your area.
Why Water Quality Matters
Every year, the EPA tracks violations of the Safe Drinking Water Act across tens of thousands of public water systems. Many communities face ongoing issues with contaminants like lead, disinfection byproducts, and bacteria. WaterCheck makes this data accessible so you can make informed decisions about the water you and your family drink every day.
Browse by State
Select a state to see its water quality overview.