Water quality · Oklahoma
Water quality in Oklahoma
Water quality (EPA SDWIS) data for ZIP codes in Oklahoma. 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 →
Oklahoma top concern
Tornadoes, induced seismicity, water-supply
Oklahoma sits in the heart of Tornado Alley. Induced seismicity (oil/gas wastewater injection) has flagged some EPA SDWIS small systems. Radon risk is Zone 1-2 across most counties.
See Oklahoma state page for the full state-level rollup across all 12 dimensions.
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