Water Quality Report · Updated May 12, 2026
OSHKOSH WATERWORKS
OSHKOSH WATERWORKS delivers tap water graded F (50/100) by TapWaterSafety.org. The utility serves approximately 63,000 residents in OSHKOSH, Wisconsin using surface water. The most significant water quality concerns are: PFAS contamination; Total PFOS and PFOA significantly above health guideline; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline.
Is OSHKOSH tap water safe to drink?
OSHKOSH WATERWORKS delivers tap water that earns a grade of F (50/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.
The utility serves 63,000 residents in OSHKOSH, drawing from surface water.
Public testing data identifies 18 contaminants in this water above EWG's health-based guidelines, including: Total PFOS and PFOA, Perfluorohexane sulfonate (PFHXS), Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Chloroform, Dichloroacetic acid, Bromodichloromethane, Perfluorononanoic acid (PFNA), Nitrate and nitrite, Nitrate, Trichloroacetic acid, Bromate, Perfluorooctanoic acid (PFOA), Dibromoacetic acid, Chromium (hexavalent), Perfluorooctane sulfonate (PFOS), Uranium. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
Quick actions for OSHKOSH residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for OSHKOSH WATERWORKS.
PFAS contamination
Severe concernPerfluorononanoic acid (PFNA), Perfluorooctane sulfonate (PFOS) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Total PFOS and PFOA significantly above health guideline
Moderate concernTotal PFOS and PFOA detected at 2.01 ppt, 287x above the EWG health guideline of 0.007 ppt.
Perfluorohexane sulfonate (PFHXS) significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS) detected at 0.167 ppt, 167x above the EWG health guideline of 0.001 ppt.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 8.75 ppb, 146x above the EWG health guideline of 0.06 ppb.
Contact OSHKOSH WATERWORKS
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for OSHKOSH
Filters matched to the specific contaminants in this water supply.
Reverse Osmosis or NSF P473 certified carbon
$80-$750Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 50/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Total PFOS and PFOA PFAS |
2.01 ppt | 0.007 | — | 100 | 100 | 0.007 | — | 287× over |
| Perfluorohexane sulfonate (PFHXS) PFAS |
0.167 ppt | 0.001 | 10.0 | — | — | — | — | 167× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
8.75 ppb | 0.06 | — | — | — | — | — | 146× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
9.54 ppb | 0.15 | 80.0 | 100 | — | — | — | 64× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
5.09 ppb | 0.1 | 60.0 | 60 | — | — | — | 51× over |
| Chloroform Disinfection byproduct |
8.45 ppb | 0.4 | — | — | — | — | — | 21× over |
| Dichloroacetic acid Disinfection byproduct |
4.28 ppb | 0.2 | — | — | — | — | — | 21× over |
| Bromodichloromethane Disinfection byproduct |
0.973 ppb | 0.06 | — | — | — | — | — | 16× over |
| Perfluorononanoic acid (PFNA) PFAS |
0.057 ppt | 0.006 | 10.0 | — | — | — | — | 9.5× over |
| Nitrate and nitrite Inorganic |
0.98 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 7.0× over |
| Nitrate Inorganic |
0.955 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 6.8× over |
| Trichloroacetic acid Disinfection byproduct |
0.551 ppb | 0.1 | — | — | — | — | — | 5.5× over |
| Bromate Disinfection byproduct |
0.405 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 4.1× over |
| Perfluorooctanoic acid (PFOA) PFAS |
0.345 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 3.8× over |
| Dibromoacetic acid Disinfection byproduct |
0.094 ppb | 0.03 | — | — | — | — | — | 3.1× over |
| Chromium (hexavalent) Heavy metal |
0.0475 ppb | 0.02 | — | — | — | — | — | 2.4× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.658 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 2.2× over |
| Uranium Radiological |
0.65 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 1.5× over |
| Atrazine Pesticide/Herbicide |
0.0102 ppb | 0.1 | 3.0 | 0.1 | 100 | 0.15 | — | Below guideline |
| Vanadium Other |
1.25 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Dibromochloromethane Disinfection byproduct |
0.00351 ppb | 0.1 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
17.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Manganese Heavy metal |
0.347 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0686 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.106 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
0.4 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
0.25 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.237 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0726 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Bromide Other |
6.82 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.634 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Nitrite Inorganic |
0.049 ppm | — | 1.0 | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
OSHKOSH WATERWORKS service area
This water system serves 1 community in Winnebago County, Wisconsin. Click any city for its dedicated tap water quality page.
Find the right filter for OSHKOSH water
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