Private Well Water Testing in South Carolina
County-by-county USGS area-risk estimates for private wells across South Carolina — arsenic exceedance probability and private-well population — plus how to test your own well at a South Carolina-certified laboratory.
South Carolina private-well risk summary
Counties covered
46
South Carolina counties with modeled risk data.
People on private wells
area estimate876,656
estimated across covered South Carolina counties.
Average arsenic risk
area estimate2%
average modeled chance a well exceeds 10 µg/L arsenic across covered counties.
South Carolina counties
- Lexington County1% arsenic exceedance (area estimate)47,434 people on private wells
- Horry County3% arsenic exceedance (area estimate)45,388 people on private wells
- York County1% arsenic exceedance (area estimate)45,021 people on private wells
- Berkeley County1% arsenic exceedance (area estimate)43,988 people on private wells
- Florence County2% arsenic exceedance (area estimate)43,769 people on private wells
- Orangeburg County2% arsenic exceedance (area estimate)31,956 people on private wells
- Spartanburg County1% arsenic exceedance (area estimate)31,252 people on private wells
- Greenville County1% arsenic exceedance (area estimate)30,558 people on private wells
- Aiken County1% arsenic exceedance (area estimate)29,391 people on private wells
- Sumter County2% arsenic exceedance (area estimate)27,146 people on private wells
- Richland County2% arsenic exceedance (area estimate)26,582 people on private wells
- Charleston County3% arsenic exceedance (area estimate)26,492 people on private wells
- Williamsburg County1% arsenic exceedance (area estimate)23,606 people on private wells
- Colleton County2% arsenic exceedance (area estimate)23,547 people on private wells
- Darlington County4% arsenic exceedance (area estimate)21,815 people on private wells
- Clarendon County1% arsenic exceedance (area estimate)21,643 people on private wells
- Dorchester County1% arsenic exceedance (area estimate)20,749 people on private wells
- Laurens County1% arsenic exceedance (area estimate)19,955 people on private wells
- Anderson County1% arsenic exceedance (area estimate)19,700 people on private wells
- Chesterfield County2% arsenic exceedance (area estimate)18,300 people on private wells
- Chester County2% arsenic exceedance (area estimate)17,897 people on private wells
- Newberry County2% arsenic exceedance (area estimate)16,233 people on private wells
- Greenwood County1% arsenic exceedance (area estimate)15,601 people on private wells
- Lancaster County2% arsenic exceedance (area estimate)15,145 people on private wells
- Beaufort County4% arsenic exceedance (area estimate)14,254 people on private wells
- Saluda County1% arsenic exceedance (area estimate)13,867 people on private wells
- Jasper County2% arsenic exceedance (area estimate)12,866 people on private wells
- Cherokee County2% arsenic exceedance (area estimate)12,496 people on private wells
- Abbeville County1% arsenic exceedance (area estimate)12,032 people on private wells
- Georgetown County2% arsenic exceedance (area estimate)11,944 people on private wells
- Kershaw County2% arsenic exceedance (area estimate)11,897 people on private wells
- Calhoun County2% arsenic exceedance (area estimate)10,923 people on private wells
- Fairfield County1% arsenic exceedance (area estimate)10,740 people on private wells
- Marion County2% arsenic exceedance (area estimate)10,341 people on private wells
- Barnwell County2% arsenic exceedance (area estimate)10,324 people on private wells
- Marlboro County2% arsenic exceedance (area estimate)10,246 people on private wells
- Hampton County1% arsenic exceedance (area estimate)10,228 people on private wells
- Oconee County1% arsenic exceedance (area estimate)9,599 people on private wells
- Edgefield County1% arsenic exceedance (area estimate)9,441 people on private wells
- Dillon County1% arsenic exceedance (area estimate)9,348 people on private wells
- Lee County2% arsenic exceedance (area estimate)8,451 people on private wells
- Pickens County1% arsenic exceedance (area estimate)6,928 people on private wells
- Bamberg County2% arsenic exceedance (area estimate)6,416 people on private wells
- Allendale County2% arsenic exceedance (area estimate)4,239 people on private wells
- Union County1% arsenic exceedance (area estimate)3,870 people on private wells
- McCormick County1% arsenic exceedance (area estimate)3,038 people on private wells
Find a South Carolina-certified testing lab
Get your well tested at a South Carolina-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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