Is Oakdale, WI tap water safe?
The short answer
2 of the 2 utilities serving Oakdale have a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and Wisconsin’s records: Tomah Waterworks and Oakdale Waterworks.
Tomah Waterworks, which serves the most people here, has 1 result above the legal limit and 1 result above the health goal. The worst: Nitrate at 14.4 ppm, above the legal limit.
The water from Tomah Waterworks is soft to hard depending on the source, 39 to 132 mg/L (2.3 to 7.7 grains per gallon). How Wisconsin’s water compares.
A town can be served by more than one utility, and some homes are on private wells. The name on your water bill tells you which is yours, and your ZIP code narrows it down. They are listed by how many people each serves in Oakdale’s ZIP codes, from EPA’s estimates.
- Open report
Tomah Waterworks
Wisconsin · serves 9,192 people · under 100 in Oakdale
1 result above the legal limit and 1 result above the health goal. The worst: Nitrate at 14.4 ppm, above the legal limit. Hardness: soft to hard depending on the source, 39 to 132 mg/L (2.3 to 7.7 grains per gallon).
11 health-based violations since 2016
- Open report
Oakdale Waterworks
Wisconsin · serves 317 people · lists Oakdale among the places it serves
Nothing in its records is above a health goal. Hardness: moderately hard, 118 mg/L (6.9 grains per gallon).
1 health-based violation since 2016
What handles it
Each of these is certified, on a certifier’s listing, for a result above a line in Tomah Waterworks’s water, which serves the most people here. Another utility’s report names what handles its own results.
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Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Nitrate
Aquasana SmartFlow Reverse Osmosis (AQ-SFRO2)
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Nitrate
Culligan 10-Cup Pitcher with ZeroWater Technology (ZEROP10)
Pitcher
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 9, 2026
Certified for: Nitrate
Water testing near Oakdale
The 3 labs Wisconsin certifies closest to Oakdale, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Monroe County Health Department
Sparta, WI · about 15 miles
Certified for bacteria
Jackson County Public Health Water Lab
Black River Falls, WI · about 25 miles
Certified for bacteria, nitrate
A1 Advanced Pumping Service, Inc.
West Salem, WI · about 30 miles
Certified for bacteria, nitrate
Wisconsin State Laboratory of Hygiene: Well water test kits ordered by phone and shipped free; you pay to mail the sample back, and the lab bills you after testing. Tests run from bacteria alone to a homeowner package covering bacteria, nitrate, fluoride, metals, hardness, volatile organic compounds and atrazine. Bacteria is $35, nitrate $35, lead $38, and the homeowner package $450, as of July 1, 2026. Public Environmental and Water Testing Prices, Wisconsin State Laboratory of Hygiene.
All 156 certified labs for WisconsinZIP codes in Oakdale
Which ZIP codes are in Oakdale: Census 2020 relationship files. Which utilities serve them, and how many people: EPA SDWIS and EPA’s service area map. Each utility’s results: EPA UCMR 5, EPA SDWIS, and EPA’s and the state’s compliance monitoring, as its report lists them. How they are measured: methodology. Certified labs: Wisconsin DNR and DATCP, certified and approved drinking water laboratories; distances from the Census 2020 ZIP code tabulation area gazetteer.
Near Oakdale
Towns nearby with a page of their own.
What to do next
- Read Tomah Waterworks’s full reportEvery result with its dates, the violations, and the certification claim that handles each finding.Open the report
- Filters for NitrateRanked by certification and what they cost over five years.The best reverse osmosis systems, ranked
- On a private well?No utility tests a well. A certified lab test is the first step.How to test well water