Private Well Water Testing in Delaware

County-by-county USGS area-risk estimates for private wells across Delaware — arsenic exceedance probability and private-well population — plus how to test your own well at a Delaware-certified laboratory.

Delaware private-well risk summary

Counties covered

Delaware counties with modeled risk data.

People on private wells

area estimate

141,361

estimated across covered Delaware counties.

Average arsenic risk

area estimate

average modeled chance a well exceeds 10 µg/L arsenic across covered counties.

Delaware counties

Find a Delaware-certified testing lab

Get your well tested at a Delaware-certified laboratory. We list certification programs by state.

Delaware certified labs

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These 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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By TapWaterData Editorial