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Water Quality Report

Mchenry, IL

McHenry County · 27,183 residents · 9 water systems

16

Contaminants detected

7

PFAS compounds

403

Hardness (mg/L)

0

Above legal limits

9

Above health guidelines

Mchenry drinking water comes from groundwater wells. Based on the most recent monitoring data, 16 contaminants have been detected in the water supply, including Lead, Nitrate, Copper, Radium, and 12 others. PFAS compounds have been detected at trace levels in Mchenry water. Water hardness is 403 mg/L (very hard), which can cause scale buildup in appliances and reduce soap effectiveness.

Contaminants detected in Mchenry water

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

Lead0.0067 / 0.015 mg/L
45% of EPA limit
Nitrate0.3 / 10 mg/L
3% of EPA limit
Copper490 / 1300 ug/L
38% of EPA limit
Radium1.1 / 5 pCi/L
21% of EPA limit
Total Trihalomethanes46.5 / 80 ug/L
58% of EPA limit
18% of EPA limit
Barium0.088 / 2 mg/L
4% of EPA limit
Fluoride0.375 / 4 mg/L
9% of EPA limit
PFHpA (Perfluoroheptanoic Acid)0.6 ng/L
UnregulatedPFAS
PFPeA (Perfluoropentanoic Acid)1.8 ng/L
UnregulatedPFAS
cis-1,2-Dichloroethylene0.97 / 70 ug/L
1% of EPA limit
Methyl Tert Butyl Ether1.6 ug/L
Unregulated
Phosphorus Total12 ug/L
Unregulated
Orthophosphate320 ug/L
Unregulated
Lithium9.1 ug/L
Unregulated
PFBA (Perfluorobutanoic Acid)2.5 ng/L
UnregulatedPFAS
PFAS (7 compounds detected)
Microplastics (not routinely tested)

Other cities in McHenry County

Water quality reports for nearby Illinois communities.

Frequently asked questions

Is Mchenry, IL tap water safe to drink?
Mchenry tap water meets EPA legal standards (Maximum Contaminant Levels). However, 9 contaminants are present above independent health guidelines, which are often stricter than legal limits. 16 contaminants have been detected in the water supply, including Lead, Nitrate, Copper, Radium, Total Trihalomethanes. 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 Mchenry water?
Monitoring has detected 16 contaminants in Mchenry's water supply: Lead, Nitrate, Copper, Radium, Total Trihalomethanes, Haloacetic Acids (HAA5), Barium, Fluoride, PFHpA (Perfluoroheptanoic Acid), PFPeA (Perfluoropentanoic Acid), cis-1,2-Dichloroethylene, Methyl Tert Butyl Ether, Phosphorus Total, Orthophosphate, Lithium, PFBA (Perfluorobutanoic Acid). Additionally, 7 PFAS compounds have been detected at trace levels. 9 exceed health guidelines. See individual system reports for concentrations relative to EPA limits.
Does Mchenry water have PFAS?
Yes. 7 PFAS compounds have been detected in Mchenry'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 Mchenry water hard?
Yes. Mchenry water has a hardness of 403 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 Mchenry get its drinking water?
Mchenry's drinking water comes from groundwater wells that draw from underground aquifers. The water is treated and tested according to Illinois EPA and EPA requirements before distribution. Mchenry is served by 9 water systems, the largest being MCHENRY (serving 22,335 people).

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