Water quality · District of Columbia
Water quality in District of Columbia
Water quality (EPA SDWIS) data for ZIP codes in District of Columbia. 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 →
District of Columbia top concern
Lead service lines (DC Water), flood
DC Water has documented elevated lead service line replacement obligations under LCRR. The Anacostia + Potomac waterfronts have FEMA AE zones; FBI UCR jurisdictional reporting for DC differs from state UCR aggregations.
See District of Columbia state page for the full state-level rollup across all 12 dimensions.
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