Well Water Nerd

Well water testing in Wisconsin

Nobody tests a private well unless the owner does. In Wisconsin, the public record says to start with PFOA, PFOS, nitrate, then bacteria every year. Below: what to order, where, what it costs, and the county-by-county results that set the order.

What to test for first

  1. 1
    PFOA
    30% of 10 local samples were above the limit.
  2. 2
    PFOS
    20% of 10 local samples were above the limit.
  3. 3
    Nitrate
    13% of 10,364 local samples were above the limit.
  4. 4
    Total coliform
    10% of 11,282 local wells tested were above the Wisconsin limit (any detection).
  5. 5
    Arsenic
    4% of 22,114 local wells tested were above the Wisconsin enforcement standard.

Test your Wisconsin well for PFOA, PFOS and nitrate

Certified lab analysis of your own tap water, bottles and prepaid return shipping included. The Essential well panel covers arsenic, uranium, nitrate, lead, copper, manganese, iron, sodium and bacteria; radon and PFAS are add-ons.

Order the Tap Score well water test kit, from $209Already tested? Upload the report

Just want bacteria checked first? Tap Score coliform and E. coli test, $99. Coliform and E. coli are the tests every well needs every year.

Want a quick look before paying for a lab? Home well water test strips on Amazon check hardness, iron, pH and nitrate in minutes. They are a screen, not a result: arsenic, bacteria, uranium and PFAS need a certified lab.

Affiliate links: the merchant pays us a commission and the price is the same for you. It does not change what the data above says. As an Amazon Associate we earn from qualifying purchases.

Where to get it tested

Three routes, and all of them work. A mail-in kit from a certified lab is the simplest: the lab ships bottles, you fill them at the kitchen tap, and results come back by email. The full panel above is $209.

A local certified lab is the second route. Laboratory Certification from Wisconsin DNR lists every lab certified for drinking water in Wisconsin. Call ahead: some take walk-in samples, some ship bottles.

The Wisconsin State Laboratory of Hygiene sells well test kits to the public, including a Homeowner Package (total coliform, E. coli, nitrate, fluoride, metals, hardness, VOCs, and atrazine screens) at $450.00, a bacteria test at $35.00, a nitrate test at $35.00, and an arsenic test at $38.00. Details from the state

Free or low-cost testing: Through the Well Testing Access Program (WellTAP), private well users may get no-cost testing through their local or Tribal health department if the well serves someone who is pregnant, a child 12 or under, or a person with a weakened immune system and a financial or other burden prevents them from testing on their own. How to get it

For questions about your well, Wells at Wisconsin DNR is the official source.

Already have results? Get the lab report read line by line, $29.

Testing by county

The contaminant most often over its limit in each county's public record, highest share first. Open a county for the full test list and its towns.

CountyTest first forOver the limit
Lafayette CountyTotal coliform26%
Rock CountyNitrate23%
Portage CountyNitrate21%
Trempealeau CountyNitrate21%
Pepin CountyTotal coliform20%
Winnebago CountyArsenic19%
Outagamie CountyArsenic19%
Green Lake CountyNitrate19%
Columbia CountyNitrate18%
Dane CountyNitrate18%
Pierce CountyTotal coliform18%
Jefferson CountyTotal coliform17%
Richland CountyTotal coliform17%
Washington CountyTotal coliform16%
Polk CountyTotal coliform15%
Dunn CountyNitrate15%
Florence CountyArsenic14%
Burnett CountyTotal coliform14%
Iowa CountyTotal coliform14%
Green CountyNitrate14%
Calumet CountyNitrate14%
Sauk CountyNitrate13%
Oconto CountyTotal coliform13%
La Crosse CountyNitrate12%
Price CountyTotal coliform12%
Shawano CountyArsenic12%
Crawford CountyTotal coliform12%
Vernon CountyTotal coliform12%
Dodge CountyTotal coliform12%
Fond du Lac CountyTotal coliform12%
Marinette CountyArsenic12%
Waupaca CountyTotal coliform12%
Chippewa CountyNitrate12%
St. Croix CountyNitrate11%
Door CountyTotal coliform11%
Lincoln CountyTotal coliform11%
Ozaukee CountyArsenic11%
Washburn CountyTotal coliform11%
Waushara CountyNitrate11%
Kewaunee CountyTotal coliform11%
Marquette CountyTotal coliform11%
Adams CountyTotal coliform10%
Menominee CountyArsenic10%
Sheboygan CountyTotal coliform10%
Manitowoc CountyTotal coliform10%
Wood CountyTotal coliform9%
Buffalo CountyNitrate9%
Marathon CountyTotal coliform9%
Taylor CountyTotal coliform9%
Clark CountyTotal coliform9%
Juneau CountyNitrate9%
Monroe CountyNitrate9%
Barron CountyNitrate9%
Douglas CountyTotal coliform9%
Walworth CountyArsenic8%
Vilas CountyTotal coliform8%
Oneida CountyLead8%
Langlade CountyTotal coliform6%
Sawyer CountyTotal coliform6%
Grant CountyNitrate6%
Racine CountyArsenic6%
Eau Claire CountyNitrate5%
Kenosha CountyArsenic5%
Jackson CountyNitrate5%
Waukesha CountyArsenic4%
Forest CountyArsenic4%
Ashland CountyArsenic4%
Brown CountyArsenic3%
Rusk CountyNitrate2%
Milwaukee CountyNitrate<1%
Bayfield CountyNitrate<1%
Iron CountyArsenic0%

Closer than the county: see the sampled wells near your address.

Free, no obligation

Get on the list for a free in-home water test in Wisconsin

We are signing licensed water treatment companies county by county. They test at your tap for free, walk you through the numbers, and quote treatment only if something needs fixing. Nothing is shared until a company joins for your area, and you get an email naming it first.

What are you worried about?

The test is free and there is no obligation. No company is named yet; your details stay with us until one joins for your area, and we log the time and address of this request.

Common questions

What should I test my well for in Wisconsin?

Start with PFOA, PFOS, nitrate. 30% of 10 local samples were above the limit. Add total coliform bacteria and nitrate every year for any private well.

Where can I get my well water tested in Wisconsin?

Use a lab certified for drinking water. Wisconsin DNR keeps the list of certified labs. A mail-in kit from a certified lab works anywhere in the state.

How much does well water testing cost in Wisconsin?

A full mail-in panel from a certified lab costs $209 (Tap Score well water test kit). A bacteria-only test costs $99 (Tap Score coliform and E. coli test). The Wisconsin State Laboratory of Hygiene sells well test kits to the public, including a Homeowner Package (total coliform, E. coli, nitrate, fluoride, metals, hardness, VOCs, and atrazine screens) at $450.00, a bacteria test at $35.00, a nitrate test at $35.00, and an arsenic test at $38.00.

Is there free well water testing in Wisconsin?

Through the Well Testing Access Program (WellTAP), private well users may get no-cost testing through their local or Tribal health department if the well serves someone who is pregnant, a child 12 or under, or a person with a weakened immune system and a financial or other burden prevents them from testing on their own.

How often should a private well be tested?

Bacteria and nitrate every year. A full panel once, then again after flooding, a change in taste, smell or color, work on the well, a new baby in the house, or a nearby result above the limit. Contaminants that come from the rock, like arsenic, radon and uranium, change slowly, so one good test and a check every few years is enough.