Well water in Sand Lake, Wisconsin

In Sand Lake, 1% of 393 private wells tested between 1999 and 2025 had nitrate above the Wisconsin enforcement standard (10 mg/L), according to the UWSP Well Water Quality Viewer.

The strongest signal is lead: 4% of 25 local wells tested were above the Wisconsin enforcement standard, too few samples to carry the headline but first on the test list below.

393 private wells tested 2000 to 2024 in state summaries; 69 test results across 9 contaminants from at least 9 wells, 1981 to 1986; nitrate has the most at 14. Data refreshed September 9, 2026.

Compiled by Nick at Well Water Nerd from public records. How these pages are built

What homeowner tests found

Wisconsin Well Water Quality Viewer samples: private wells tested and reported to the state, 2000 to 2024. Shares are against the level the state applies to each contaminant, named in the last column; several are stricter than EPA.

Contaminant	Above state level	Wells tested	Median	95th pct	Highest	State level
Iron	42%	24	208	11,250	11,390	300 ug/L
Manganese	40%	25	227	1,070	1,131	300 ug/L
Lead	4%	25	0	5	19	15 ug/L
Nitrate	1%	393	0.14	2.94	46	10 mg/L
Arsenic	0%	36	0	4.57	6.1	10 ug/L
Copper	0%	25	0.004	0.188	0.396	1.3 mg/L
Chloride	0%	25	1.4	8.5	31.4	250 mg/L
Sodium	0%	23	3.44	7.13	16.7	20 mg/L
Total coliform	0%	1

What individual samples found

Each row summarizes every public sample for that contaminant inside Sand Lake. Above limit means above the EPA maximum contaminant level; where EPA has no enforceable limit, the row shows a health guideline or nuisance level instead.

Contaminant	Above limit	Samples	Detected	Median	Highest	Limit
Nitrate 1985 to 1986	0%	14	43%	0	6.2	10 mg/L EPA limit

Sampled fewer than 10 times, too few to summarize: Lead (6), Fluoride (9), Arsenic (7), Copper (6), Chloride (9), Iron (8), Manganese (8), Sodium (2).

Closer than the town

See the sampled wells near your address

The same records, drawn around one point: which wells within a few miles were sampled and what they found, how deep the wells next to you were drilled, and any leaking tank or cleanup site within a mile.

Check my address

What this means

Among homeowners in Sand Lake who sent a sample to the state lab, the health-based limits most often exceeded were lead (4% of 25 wells) and nitrate (1% of 393 wells). These are ordinary wells tested by their owners, so the shares are the best available picture of a typical well here, with one caveat: people test more often when they suspect a problem.

Iron and manganese exceed the state's advisory level in a sizable share of wells; these are mostly a taste, staining or diet issue rather than a toxicity one.

What to test for in Sand Lake

1
Lead
4% of 25 local wells tested were above the Wisconsin enforcement standard.
2
Nitrate
1% of 393 local wells tested were above the Wisconsin enforcement standard.
3
Coliform bacteria
Recommended for every private well, every year.
4
Iron
42% of 24 local wells tested were above the Wisconsin nuisance level.
5
Manganese
40% of 25 local wells tested were above the Wisconsin enforcement standard.
6
Copper
Detected in 100% of local samples.
7
Chloride
Detected in 100% of local samples.

Test your Sand Lake well for lead, nitrate and coliform bacteria

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.

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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 a well tested in Wisconsin: certified labs, state programs and prices.

Already have results back? Get your lab report read against the Sand Lake numbers, $29. Every line explained, ranked by what matters, with the fix for each.

The rock under Sand Lake

Not a principal aquifer

The USGS map places this area outside any principal aquifer, which usually means wells here draw from fractured bedrock or thin local deposits rather than a large regional aquifer. Bedrock wells of that kind are where arsenic, radon and uranium turn up, and yields vary from well to well.

Classification from the USGS Principal Aquifers of the United States (national map, 2003 edition, GIS release 2015), read at the town centroid. A single well can sit in a different unit, especially near a boundary.

Official help in Wisconsin

Two places to start that are not selling anything: the state program that answers private well questions, and its list of labs certified to run drinking water tests. A certified lab is the difference between a result you can act on and a number.

Wells, Wisconsin DNR
Laboratory Certification, Wisconsin DNR

Contamination sources on record in Sand Lake

Wisconsin DNR records 3 regulated sites in Sand Lake, among 3 regulated sites in total. Groundwater does not follow property lines, so a well within a few hundred feet of one of these is worth testing for what that site could release.

3: lined landfills and transfer facilities

Treatment that fits the local profile

Iron

Oxidizing filter whole-house; Water softener (low levels); Aeration plus filtration

Manganese

Oxidizing filter (greensand, birm) whole-house; Water softener (low levels); Point-of-use reverse osmosis

Systems we would look at first

Some links below are affiliate links. If you buy through one, the merchant pays us a commission at no extra cost to you. It does not change which products we list or what the data says.

For iron

Iron and manganese oxidizing filter

whole-house, at the point of entry, about $1,800

Air-injection or greensand media; fixes staining at the source.

Free, no obligation

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

No water treatment company serves Sand Lake through Well Water Nerd yet. We are signing licensed companies on county by county: they test at your tap for free, walk you through the numbers, and quote treatment only if something needs fixing. Leave your details and you are first in line. Nothing is shared until a company joins for Sand Lake, and you get an email naming it first.

Common questions

How often should I test a private well in Sand Lake?

Test for bacteria and nitrate every year. Test once for arsenic, uranium, radon, fluoride, manganese and PFAS, then again every three to five years or after any change in taste, color, or plumbing.

Towns near Sand Lake

Closest first. Groundwater does not stop at a line on a map, so the next town over is a fair second opinion.

Want the numbers themselves? Download the Wisconsin dataset as CSV, every county and town, with the sources named.

Sources

USGS Water Quality Portal: 69 samples in Sand Lake. Data from the Water Quality Portal, a service of USGS, EPA and USDA; groundwater samples collected by USGS and cooperators. Retrieved September 3, 2026.
Wisconsin Well Water Quality Viewer samples: summaries for 9 contaminants in Sand Lake, up to 393 wells each. Private well samples compiled by the UWSP Center for Watershed Science and Education from the DNR Groundwater Retrieval Network, DATCP surveys, the UWSP Water and Environmental Analysis Lab and county health programs, published in the Wisconsin Well Water Quality Viewer with Wisconsin DHS. Samples are located to the town, village or city they fall in; one result per well and parameter (the latest) so repeat samples do not double count; wells without a state well number are keyed by location. Shares are against Wisconsin NR 140 enforcement standards (arsenic 10 ug/L, nitrate 10 mg/L as N, manganese 300 ug/L, lead 15 ug/L, copper 1.3 mg/L) and the iron and chloride secondary levels. Many samples were submitted by homeowners with a reason to test, so shares can run above a random survey. Retrieved September 9, 2026.
Wisconsin DNR regulated sites: 3 regulated sites located in Sand Lake. Open and closed remediation activities (BRRTS, including leaking underground storage tanks and spills) and landfill and waste sites from the Wisconsin Department of Natural Resources. Retrieved September 9, 2026.

Non-detects count as samples and are treated as zero when computing medians. Exactly at the limit counts as not above it. A sample belongs to the town containing the well's reported coordinates.