Tap Water Quality Report
Tap water quality in OSHKOSH, Wisconsin
Tap water in OSHKOSH, Wisconsin receives a grade of D (61/100) from TapWaterSafety.org. It's served by OSHKOSH WATERWORKS. 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. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in OSHKOSH's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving OSHKOSH.
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.
EPA compliance record
Official U.S. EPA records for OSHKOSH WATERWORKS (system ID WI4710457) for the last 3 years. Checked 2026-10-07.
| Rule | Type | Since | Status |
|---|---|---|---|
| Stage 1 Disinfectants and Disinfection Byproducts Rule | Missed testing or reporting | 07/01/2023 | Resolved |
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for OSHKOSH
Filters matched to the specific contaminants in OSHKOSH's water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in OSHKOSH's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. 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, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from OSHKOSH WATERWORKS.