Private Well Water Testing in District of Columbia
County-by-county USGS area-risk estimates for private wells across District of Columbia — arsenic exceedance probability and private-well population — plus how to test your own well at a District of Columbia-certified laboratory.
District of Columbia private-well risk summary
Counties covered
1
District of Columbia counties with modeled risk data.
People on private wells
area estimate576
estimated across covered District of Columbia counties.
Average arsenic risk
area estimate3%
average modeled chance a well exceeds 10 µg/L arsenic across covered counties.
District of Columbia counties
Find a District of Columbia-certified testing lab
Get your well tested at a District of Columbia-certified laboratory. We list certification programs by state.
Already tested your well? Get a free plain-English reading
Upload your well water lab report (PDF or a photo) and our team will email you a full, plain-English reading of every result — free. Educational only, never medical advice.
Your upload also helps us keep local water data accurate — we only ever share anonymized, area-level summaries.
Upload my well testThese figures are USGS area estimates: statistical groundwater models describing how likely elevated contaminant levels are across a county. They are not designed to predict the concentration in any single well. Only testing your own well reveals its water quality.
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