Private Well Water Testing in New Jersey
County-by-county USGS area-risk estimates for private wells across New Jersey — arsenic exceedance probability and private-well population — plus how to test your own well at a New Jersey-certified laboratory.
New Jersey private-well risk summary
Counties covered
21
New Jersey counties with modeled risk data.
People on private wells
area estimate767,463
estimated across covered New Jersey counties.
Average arsenic risk
area estimate3%
average modeled chance a well exceeds 10 µg/L arsenic across covered counties.
New Jersey counties
- Ocean County4% arsenic exceedance (area estimate)70,464 people on private wells
- Morris County3% arsenic exceedance (area estimate)66,483 people on private wells
- Sussex County2% arsenic exceedance (area estimate)64,817 people on private wells
- Atlantic County3% arsenic exceedance (area estimate)60,935 people on private wells
- Burlington County2% arsenic exceedance (area estimate)60,278 people on private wells
- Hunterdon County7% arsenic exceedance (area estimate)58,523 people on private wells
- Somerset County8% arsenic exceedance (area estimate)49,023 people on private wells
- Cumberland County3% arsenic exceedance (area estimate)41,671 people on private wells
- Monmouth County3% arsenic exceedance (area estimate)39,198 people on private wells
- Gloucester County3% arsenic exceedance (area estimate)35,817 people on private wells
- Cape May County5% arsenic exceedance (area estimate)33,956 people on private wells
- Warren County2% arsenic exceedance (area estimate)32,603 people on private wells
- Passaic County2% arsenic exceedance (area estimate)27,005 people on private wells
- Bergen County3% arsenic exceedance (area estimate)24,908 people on private wells
- Mercer County4% arsenic exceedance (area estimate)24,748 people on private wells
- Salem County3% arsenic exceedance (area estimate)24,494 people on private wells
- Camden County3% arsenic exceedance (area estimate)24,047 people on private wells
- Middlesex County3% arsenic exceedance (area estimate)20,776 people on private wells
- Essex County2% arsenic exceedance (area estimate)5,107 people on private wells
- Union County2% arsenic exceedance (area estimate)2,183 people on private wells
- Hudson County4% arsenic exceedance (area estimate)427 people on private wells
Find a New Jersey-certified testing lab
Get your well tested at a New Jersey-certified laboratory. We list certification programs by state.
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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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