Private Well Water Testing in New York
County-by-county USGS area-risk estimates for private wells across New York โ arsenic exceedance probability and private-well population โ plus how to test your own well at a New York-certified laboratory.
New York private-well risk summary
Counties covered
62
New York counties with modeled risk data.
People on private wells
area estimate1,859,330
estimated across covered New York counties.
Average arsenic risk
area estimate7%
average modeled chance a well exceeds 10 ยตg/L arsenic across covered counties.
New York counties
- Suffolk County7% arsenic exceedance (area estimate)120,590 people on private wells
- Dutchess County3% arsenic exceedance (area estimate)97,130 people on private wells
- Orange County2% arsenic exceedance (area estimate)85,169 people on private wells
- Ulster County3% arsenic exceedance (area estimate)81,457 people on private wells
- St. Lawrence County4% arsenic exceedance (area estimate)54,954 people on private wells
- Oswego County4% arsenic exceedance (area estimate)53,206 people on private wells
- Saratoga County5% arsenic exceedance (area estimate)51,705 people on private wells
- Broome County7% arsenic exceedance (area estimate)51,196 people on private wells
- Rensselaer County5% arsenic exceedance (area estimate)50,846 people on private wells
- Westchester County6% arsenic exceedance (area estimate)49,344 people on private wells
- Oneida County4% arsenic exceedance (area estimate)47,756 people on private wells
- Putnam County5% arsenic exceedance (area estimate)46,992 people on private wells
- Erie County10% arsenic exceedance (area estimate)45,043 people on private wells
- Steuben County7% arsenic exceedance (area estimate)44,319 people on private wells
- Chautauqua County7% arsenic exceedance (area estimate)42,840 people on private wells
- Sullivan County3% arsenic exceedance (area estimate)40,793 people on private wells
- Columbia County5% arsenic exceedance (area estimate)37,950 people on private wells
- Jefferson County4% arsenic exceedance (area estimate)37,011 people on private wells
- Clinton County4% arsenic exceedance (area estimate)34,041 people on private wells
- Onondaga County4% arsenic exceedance (area estimate)33,872 people on private wells
- Cattaraugus County5% arsenic exceedance (area estimate)33,666 people on private wells
- Washington County7% arsenic exceedance (area estimate)31,725 people on private wells
- Tioga County7% arsenic exceedance (area estimate)29,908 people on private wells
- Tompkins County7% arsenic exceedance (area estimate)29,399 people on private wells
- Otsego County6% arsenic exceedance (area estimate)28,216 people on private wells
- Chenango County7% arsenic exceedance (area estimate)27,081 people on private wells
- Cayuga County6% arsenic exceedance (area estimate)26,520 people on private wells
- Genesee County15% arsenic exceedance (area estimate)26,164 people on private wells
- Madison County7% arsenic exceedance (area estimate)26,104 people on private wells
- Chemung County6% arsenic exceedance (area estimate)25,958 people on private wells
- Greene County4% arsenic exceedance (area estimate)25,316 people on private wells
- Ontario County13% arsenic exceedance (area estimate)24,272 people on private wells
- Wayne County5% arsenic exceedance (area estimate)23,104 people on private wells
- Allegany County8% arsenic exceedance (area estimate)22,750 people on private wells
- Franklin County3% arsenic exceedance (area estimate)22,513 people on private wells
- Albany County6% arsenic exceedance (area estimate)22,453 people on private wells
- Wyoming County29% arsenic exceedance (area estimate)21,548 people on private wells
- Delaware County5% arsenic exceedance (area estimate)21,521 people on private wells
- Livingston County20% arsenic exceedance (area estimate)21,213 people on private wells
- Fulton County3% arsenic exceedance (area estimate)21,099 people on private wells
- Herkimer County2% arsenic exceedance (area estimate)20,637 people on private wells
- Schoharie County4% arsenic exceedance (area estimate)20,063 people on private wells
- Orleans County16% arsenic exceedance (area estimate)19,425 people on private wells
- Montgomery County5% arsenic exceedance (area estimate)18,688 people on private wells
- Monroe County8% arsenic exceedance (area estimate)17,439 people on private wells
- Rockland County2% arsenic exceedance (area estimate)17,358 people on private wells
- Cortland County6% arsenic exceedance (area estimate)17,307 people on private wells
- Warren County4% arsenic exceedance (area estimate)15,189 people on private wells
- Lewis County2% arsenic exceedance (area estimate)13,193 people on private wells
- Yates County15% arsenic exceedance (area estimate)13,000 people on private wells
- Seneca County13% arsenic exceedance (area estimate)12,529 people on private wells
- Schuyler County11% arsenic exceedance (area estimate)12,022 people on private wells
- Schenectady County4% arsenic exceedance (area estimate)11,641 people on private wells
- Essex County2% arsenic exceedance (area estimate)9,159 people on private wells
- Niagara County7% arsenic exceedance (area estimate)6,256 people on private wells
- Kings County7% arsenic exceedance (area estimate)5,363 people on private wells
- Nassau County6% arsenic exceedance (area estimate)4,939 people on private wells
- Queens County6% arsenic exceedance (area estimate)3,846 people on private wells
- Hamilton County1% arsenic exceedance (area estimate)2,305 people on private wells
- Bronx County7% arsenic exceedance (area estimate)1,234 people on private wells
- New York County8% arsenic exceedance (area estimate)753 people on private wells
- Richmond County5% arsenic exceedance (area estimate)240 people on private wells
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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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