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Well water testing in Douglas County, South Dakota

What official data says about private wells in Douglas County, what to test for, and the state-certified labs nearby.

People on private wells (2015)1,336

About 45% of the county's 2,977 residents. Rank 22 of 66 in South Dakota.

Arsenic above EPA’s limit (USGS estimate)about 1 people

95% range 0 to 2 private-well users (2010 base year). Rank 27 of 66 in South Dakota.

EPA radon zone (indoor air)Zone 1

Highest potential (average indoor radon may be greater than 4 pCi/L). EPA says the map should not be used to decide whether an individual home needs testing.

Certified labs in this county0

Labs with an address in this county, from the official state lists on this site, matched by ZIP code.

What to test for in Douglas County

Private wells are not regulated like public water: EPA advises owners to test their well every year for total coliform bacteria, nitrates, total dissolved solids and pH. Your state's own schedule:

  • South Dakota DANR recommends retesting a well for bacteria at least once a year. After heavy rain, snowmelt or flooding near your well, it says to submit a sample for at least bacteria and nitrate. source

Arsenic. USGS estimates that about 1 people using private wells in Douglas County had arsenic above 10 µg/L, EPA's limit for public water (2010 base year; 95% range 0 to 2). USGS describes this kind of estimate as useful "for broad screening of the population at risk", so it says nothing certain about any one well. Arsenic has no taste or smell: test for it by name.

Radon. EPA puts Douglas County in Zone 1: highest potential (average indoor radon may be greater than 4 pCi/L). That map is about radon in indoor air, and EPA says it should not be used to decide whether an individual home needs testing. If radon is found in your air and you have a well, EPA suggests testing the water too: see radon in well water.

For anything specific to your home (farms nearby, old plumbing, a new baby, a smell or stain), use the which-tests checklist. When the results arrive, check your numbers against EPA's limits.

Estimated private-well users with arsenic above 10 µg/L: Douglas County and South Dakota's highest countiespeople (2010 base year)
Show the numbers
ItemValueNote
Pennington County343 people (2010 base year)
Meade County227 people (2010 base year)
Custer County108 people (2010 base year)
Lincoln County80 people (2010 base year)
Perkins County73 people (2010 base year)
Douglas County (this county)1 people (2010 base year)

USGS model estimate for broad screening, not a measurement of any well. Only a test tells you about your own well. Source: USGS, Estimated county level domestic well population with arsenic greater than 10 micrograms per liter (Ayotte, Medalie and Qi, 2017), accessed 2026-11-01.

Testing programs and help in South Dakota

  • Sample bottles and instructions for the state public health lab are also available from County Extension offices. source

Buying a home with a well in Douglas County

Loan test (FHA, VA, USDA) in Douglas County, SD

  • VA. Test results are valid for 90 days from the date the local health authority certifies them, unless the local authority says otherwise. VA’s chapter names no list of contaminants: the water must meet the local health authority’s requirements, or EPA guidelines where it has none. Your lender may ask for specific tests.
  • FHA. A well test is required in the situations FHA’s handbook lists, among others, and the report may not be more than 180 days old at disbursement.
  • USDA. Guaranteed loans need a water quality test for a private well, done by the local health authority or a state-certified lab, and no more than 180 days old at closing.

Lenders can ask for more (extra tests, a particular lab, who takes the sample): ask your lender before you book. Federal rules as read on Nov 3, 2026 source 1 source 2 source 3. Full comparison: VA, FHA and USDA well water test requirements. Loan test kits sold by mail, with price and days to results: kits compared.

State-certified labs in Douglas County

None of the labs on our South Dakota list has an address in Douglas County. Labs elsewhere in the state may take samples by mail or courier: ask the lab, and check the hold time for bacteria before you send one.

Testing by mail from Douglas County. South Dakota Public Health Laboratory, Environmental Laboratory Testing Fees, per-test prices publishes these prices: Total coliform $20; E. coli $22; Nitrate $18 (checked 2 Nov 2026) source. All South Dakota state-lab prices and how to get a kit.

Labs on the South Dakota list whose own websites say they take homeowner samples: Mid Continent Testing Laboratory (Rapid City), Minnesota Valley Testing Laboratories (Bismarck), South Dakota State Health Laboratory (Pierre). Use Check my ZIP to sort labs by distance.

See all South Dakota labs in the finder and filter by the test you need and by labs that take homeowner samples.

Sources and method Private-well population is the USGS 2015 estimate of people on domestic self-supplied water. The arsenic figure is a USGS model estimate on a 2010 population base, not a count of tested wells. Labs are placed in a county by the ZIP code on the state list. These figures come from different USGS products, years and methods, so they can disagree with each other (for example, the arsenic estimate and the well population use different base years). Read them as context for the county, not as facts about any one well. Checked 1 Nov 2026. General information, not medical advice.
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