Sherwood Waterworks
What EPA’s and Wisconsin’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.
- Serves
- 3,114 people
- Connections
- 1,153
- Water source
- Surface water bought from another system
- Based in
- Sherwood, WI
- County
- Calumet
- Owner
- Local government
The ZIP code it serves
The short answer
Nothing in EPA’s and Wisconsin’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. 1 health-based violation since 2016.
What was found
Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 1.8 ppm, for the period ending Dec. 31, 1993. None since is on file, so it is not counted as a current finding.
Total trihalomethanes (TTHM) and haloacetic acids (HAA5): Wisconsin’s own results, samples taken from Jan. 14, 2020 to July 14, 2026, with EPA’s 2012 to 2019 file for earlier years.
Below EPA’s limits2
Total trihalomethanes (TTHM)
Forms or is added in treatment
37.1ppb
Highest yearly average, 2020 to 2026
2026 average: 34.4 ppb
Averaged by year, the highest was 37.1 ppb, in 2022, below EPA’s legal limit of 80 ppb. Its highest single sample was 48.7 ppb. In 2026, the latest year on file, its three samples averaged 34.4 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 44.2 ppb, in 2017.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Haloacetic acids (HAA5)
Forms or is added in treatment
19.7ppb
Highest yearly average, 2020 to 2026
2026 average: 17.8 ppb
Averaged by year, the highest was 19.7 ppb, in 2025, below EPA’s legal limit of 60 ppb. Its highest single sample was 23.4 ppb. In 2026, the latest year on file, its three samples averaged 17.8 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 22.4 ppb, in 2019.
What handles it
No certification claim covers this compound yet.
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Lead
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Lead and Copper Rule Revisions | The required inventory of lead service lines was not completed or submitted on time.EPA: LSL Inventory | Oct. 17, 2024 | — | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 4 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Total trihalomethanes (TTHM) and haloacetic acids (HAA5) results here are Wisconsin’s own from 2020 on, with EPA’s national file for 2012 to 2019. Sherwood Waterworks’s own annual report, which it must send you every year, has the contaminants this page does not show.
Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.
What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.
Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Wisconsin’s results run from Jan. 14, 2020 to July 14, 2026.
Testing your own tap
The 3 labs Wisconsin certifies closest to the area Sherwood Waterworks serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Outagamie County Public Health Lab
Appleton, WI · about 9 miles
Certified for bacteria
Farm First Dairy Cooperative
Kaukauna, WI · about 9 miles
Certified for bacteria
Clean Water Testing LLC
Appleton, WI · about 11 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics
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 WisconsinSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- Wisconsin Department of Natural Resources, Drinking Water Program, results from Jan. 2, 2020 to Oct. 5, 2026, read Oct. 8, 2026
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: Wisconsin DNR and DATCP, certified and approved drinking water laboratories, read Oct. 10, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID WI4080271. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Nothing here is above a health goalIn EPA’s and Wisconsin’s records for this utility. They don’t cover everything, which is why the next step matters.Every contaminant TapBuff tracks
- Get the utility’s own reportSherwood Waterworks must send you a water quality report every year. It covers contaminants this page does not show.How to read it
- Test your own tap for leadYour service line, solder and fixtures decide the lead at your faucet, not the utility’s average.Lead in your water: what to do
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded