Water quality · Hawaii
Water quality in Hawaii
Water quality (EPA SDWIS) data for ZIP codes in Hawaii. 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 →
Hawaii top concern
Tsunami, lava-zone, water-source isolation
Hawaii's federated data is unusual: FEMA tsunami evacuation zones are state-managed alongside NFHL flood maps; Big Island lava-flow zones (USGS) overlay FEMA hazard layers. Each island operates independent water utilities, so EPA SDWIS PWSIDs do not aggregate across the state.
See Hawaii state page for the full state-level rollup across all 12 dimensions.
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