Before you look up your water

This map shows reported compliance data, not water testing. Grades reflect violations that water systems and states reported to EPA's Safe Drinking Water Information System. EPA acknowledges underreporting; a system with no reported violations is not guaranteed to have none.

Data lags 3–6 months by design. States report each quarter's violations the following quarter after a verification period.

The grades are ours, not EPA's. We weight violations by contaminant severity, recency, and resolution status. Read the full methodology.

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