Water quality · Ohio
Water quality in Ohio
Water quality (EPA SDWIS) data for ZIP codes in Ohio. Pick a ZIP below to dive into the water quality summary.
Last verified 2026-05-13 · methodology
What lands here
Pages show the CWS serving the address, any health-based violations in the last 3 years, most recent lead and copper sampling result, and a link to the primary SDWIS record.
Source & refresh
EPA SDWIS. Refreshed quarterly (federal mandate). Primary source →
Ohio top concern
Lead service lines, Great Lakes erosion
Ohio has heavy LCRR obligations in Cleveland, Cincinnati, Columbus, Toledo. Lake Erie shoreline erosion expands FEMA AE zones in some lakefront counties. Tornado exposure on the Indiana/Ohio border.
See Ohio state page for the full state-level rollup across all 12 dimensions.
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