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Water Quality Report

Oshkosh, WI

Winnebago County · 67,076 residents · 4 water systems

22

Contaminants detected

6

PFAS compounds

380

Hardness (mg/L)

0

Above legal limits

8

Above health guidelines

Oshkosh drinking water comes from a mix of groundwater and surface water sources. Based on the most recent monitoring data, 22 contaminants have been detected in the water supply, including Lead, Nitrate, Arsenic, Copper, and 18 others. PFAS compounds have been detected at trace levels in Oshkosh water. Water hardness is 380 mg/L (very hard), which can cause scale buildup in appliances and reduce soap effectiveness.

Contaminants detected in Oshkosh water

Detection does not necessarily mean unsafe levels. See individual reports for concentrations and EPA limits.

Lead0.0061 / 0.015 mg/L
41% of EPA limit
Nitrate1 / 10 mg/L
10% of EPA limit
Arsenic0.0033 / 0.01 mg/L
33% of EPA limit
Copper88 / 1300 ug/L
7% of EPA limit
Radium1.3 / 5 pCi/L
27% of EPA limit
Uranium0.56 / 30 ug/L
2% of EPA limit
Total Trihalomethanes8.6 / 80 ug/L
11% of EPA limit
Haloacetic Acids (HAA5)6.3 / 60 ug/L
11% of EPA limit
Atrazine0.017 / 3 ug/L
1% of EPA limit
Nickel0.0013 mg/L
UnregulatedInorganic
Selenium0.0099 / 0.05 mg/L
20% of EPA limit
Xylenes0.77 / 10000 ug/L
0% of EPA limit
Fluoride0.658 / 4 mg/L
16% of EPA limit
Bromate0.0041 / 0.01 mg/L
41% of EPA limit
PFHpA (Perfluoroheptanoic Acid)0.89 ng/L
UnregulatedPFAS
Carbon Tetrachloride0.82 / 5 ug/L
16% of EPA limit
Ethylbenzene0.42 / 700 ug/L
0% of EPA limit
Barium0.013 / 2 mg/L
1% of EPA limit
Nitrite0.031 / 1 mg/L
3% of EPA limit
Toc6.3 mg/L
Unregulated
Orthophosphate2240 ug/L
Unregulated
Bromide0.012 mg/L
Unregulated
PFAS (6 compounds detected)
Microplastics (not routinely tested)

Water systems serving Oshkosh

OSHKOSH WATERWORKS

63,000 servedSurface water22 contaminants5 above guidelines
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ALGOMA TN SANITARY DIST 1

3,935 servedGroundwater20 contaminants1 above guideline
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WINNEBAGO AREA SANITARY DISTRICT

90 servedSurface water4 contaminants1 above guideline
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SILVERCREST APARTMENTS

51 servedGroundwater9 contaminants1 above guideline
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Other cities in Winnebago County

Water quality reports for nearby Wisconsin communities.

NeenahOmroWinneconne

Frequently asked questions

Is Oshkosh, WI tap water safe to drink?
Oshkosh tap water meets EPA legal standards (Maximum Contaminant Levels). However, 8 contaminants are present above independent health guidelines, which are often stricter than legal limits. 22 contaminants have been detected in the water supply, including Lead, Nitrate, Arsenic, Copper, Radium. View the detailed report for each water system to see specific levels and how they compare to both legal limits and health guidelines.
What contaminants are in Oshkosh water?
Monitoring has detected 22 contaminants in Oshkosh's water supply: Lead, Nitrate, Arsenic, Copper, Radium, Uranium, Total Trihalomethanes, Haloacetic Acids (HAA5), Atrazine, Nickel, Selenium, Xylenes, Fluoride, Bromate, PFHpA (Perfluoroheptanoic Acid), Carbon Tetrachloride, Ethylbenzene, Barium, Nitrite, Toc, Orthophosphate, Bromide. Additionally, 6 PFAS compounds have been detected at trace levels. 8 exceed health guidelines. See individual system reports for concentrations relative to EPA limits.
Does Oshkosh water have PFAS?
Yes. 6 PFAS compounds have been detected in Oshkosh's water supply at trace levels. PFAS are sometimes called "forever chemicals" because they do not break down in the environment. The EPA has set Maximum Contaminant Levels for several PFAS compounds. View the detailed report for specific concentrations.
Is Oshkosh water hard?
Yes. Oshkosh water has a hardness of 380 mg/L (very hard). Hard water is not a health concern but can cause scale buildup in water heaters and appliances, reduce soap effectiveness, and leave mineral deposits. Water softeners or conditioning systems can address hardness.
Where does Oshkosh get its drinking water?
Oshkosh's drinking water comes from a combination of groundwater and surface water sources. The water is treated and tested according to Wisconsin DNR and EPA requirements before distribution. Oshkosh is served by 4 water systems, the largest being OSHKOSH WATERWORKS (serving 63,000 people).

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