Private Well Water Testing in South Dakota
County-by-county USGS area-risk estimates for private wells across South Dakota โ arsenic exceedance probability and private-well population โ plus how to test your own well at a South Dakota-certified laboratory.
South Dakota private-well risk summary
Counties covered
66
South Dakota counties with modeled risk data.
People on private wells
area estimate120,041
estimated across covered South Dakota counties.
Average arsenic risk
area estimate4%
average modeled chance a well exceeds 10 ยตg/L arsenic across covered counties.
South Dakota counties
- Pennington County3% arsenic exceedance (area estimate)11,335 people on private wells
- Minnehaha County5% arsenic exceedance (area estimate)9,149 people on private wells
- Meade County3% arsenic exceedance (area estimate)8,110 people on private wells
- Lawrence County2% arsenic exceedance (area estimate)7,176 people on private wells
- Oglala Lakota County4% arsenic exceedance (area estimate)5,461 people on private wells
- Custer County3% arsenic exceedance (area estimate)4,756 people on private wells
- Beadle County3% arsenic exceedance (area estimate)4,637 people on private wells
- Roberts County6% arsenic exceedance (area estimate)4,095 people on private wells
- Brown County10% arsenic exceedance (area estimate)3,426 people on private wells
- Codington County5% arsenic exceedance (area estimate)3,361 people on private wells
- Brookings County4% arsenic exceedance (area estimate)3,066 people on private wells
- Union County4% arsenic exceedance (area estimate)2,952 people on private wells
- Todd County3% arsenic exceedance (area estimate)2,912 people on private wells
- Spink County6% arsenic exceedance (area estimate)2,209 people on private wells
- Fall River County4% arsenic exceedance (area estimate)1,821 people on private wells
- Davison County3% arsenic exceedance (area estimate)1,674 people on private wells
- Butte County3% arsenic exceedance (area estimate)1,645 people on private wells
- Lincoln County6% arsenic exceedance (area estimate)1,637 people on private wells
- Corson County5% arsenic exceedance (area estimate)1,556 people on private wells
- Turner County5% arsenic exceedance (area estimate)1,533 people on private wells
- Marshall County8% arsenic exceedance (area estimate)1,522 people on private wells
- Perkins County4% arsenic exceedance (area estimate)1,483 people on private wells
- Grant County7% arsenic exceedance (area estimate)1,442 people on private wells
- Hand County5% arsenic exceedance (area estimate)1,441 people on private wells
- Bennett County4% arsenic exceedance (area estimate)1,440 people on private wells
- Jackson County3% arsenic exceedance (area estimate)1,416 people on private wells
- Sanborn County3% arsenic exceedance (area estimate)1,315 people on private wells
- Hughes County3% arsenic exceedance (area estimate)1,256 people on private wells
- Lake County4% arsenic exceedance (area estimate)1,256 people on private wells
- Day County3% arsenic exceedance (area estimate)1,102 people on private wells
- McCook County4% arsenic exceedance (area estimate)1,009 people on private wells
- Yankton County5% arsenic exceedance (area estimate)980 people on private wells
- Hutchinson County4% arsenic exceedance (area estimate)935 people on private wells
- Hamlin County5% arsenic exceedance (area estimate)913 people on private wells
- Moody County5% arsenic exceedance (area estimate)903 people on private wells
- Tripp County2% arsenic exceedance (area estimate)877 people on private wells
- Douglas County3% arsenic exceedance (area estimate)858 people on private wells
- Aurora County3% arsenic exceedance (area estimate)854 people on private wells
- Gregory County2% arsenic exceedance (area estimate)846 people on private wells
- Harding County5% arsenic exceedance (area estimate)824 people on private wells
- Charles Mix County2% arsenic exceedance (area estimate)818 people on private wells
- McPherson County7% arsenic exceedance (area estimate)804 people on private wells
- Miner County3% arsenic exceedance (area estimate)783 people on private wells
- Faulk County5% arsenic exceedance (area estimate)779 people on private wells
- Jerauld County4% arsenic exceedance (area estimate)755 people on private wells
- Lyman County3% arsenic exceedance (area estimate)755 people on private wells
- Dewey County3% arsenic exceedance (area estimate)750 people on private wells
- Clark County3% arsenic exceedance (area estimate)717 people on private wells
- Deuel County6% arsenic exceedance (area estimate)707 people on private wells
- Edmunds County5% arsenic exceedance (area estimate)706 people on private wells
- Kingsbury County5% arsenic exceedance (area estimate)703 people on private wells
- Clay County4% arsenic exceedance (area estimate)689 people on private wells
- Bon Homme County3% arsenic exceedance (area estimate)604 people on private wells
- Sully County4% arsenic exceedance (area estimate)588 people on private wells
- Haakon County3% arsenic exceedance (area estimate)555 people on private wells
- Ziebach County4% arsenic exceedance (area estimate)498 people on private wells
- Potter County4% arsenic exceedance (area estimate)490 people on private wells
- Campbell County5% arsenic exceedance (area estimate)478 people on private wells
- Hyde County4% arsenic exceedance (area estimate)472 people on private wells
- Hanson County3% arsenic exceedance (area estimate)467 people on private wells
- Mellette County3% arsenic exceedance (area estimate)421 people on private wells
- Stanley County3% arsenic exceedance (area estimate)393 people on private wells
- Buffalo County4% arsenic exceedance (area estimate)368 people on private wells
- Walworth County4% arsenic exceedance (area estimate)310 people on private wells
- Brule County3% arsenic exceedance (area estimate)132 people on private wells
- Jones County3% arsenic exceedance (area estimate)116 people on private wells
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Get your well tested at a South Dakota-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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