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Water Quality Report

Monticello, WI

Green County · 1,217 residents · 1 water system

15

Contaminants detected

0

PFAS compounds

360

Hardness (mg/L)

0

Above legal limits

3

Above health guidelines

Monticello drinking water comes from groundwater wells. Based on the most recent monitoring data, 15 contaminants have been detected in the water supply, including Lead, Nitrate, Arsenic, Copper, and 11 others. PFAS testing has been conducted with no detections. Water hardness is 360 mg/L (very hard), which can cause scale buildup in appliances and reduce soap effectiveness.

Contaminants detected in Monticello water

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

Lead0.00025 / 0.015 mg/L
2% of EPA limit
Nitrate6.8 / 10 mg/L
68% of EPA limit
Arsenic0.0011 / 0.01 mg/L
11% of EPA limit
Copper2.1 / 1300 ug/L
0% of EPA limit
Radon113 pCi/L
UnregulatedRadionuclide
Radium2.9 / 5 pCi/L
57% of EPA limit
Uranium0.53 / 30 ug/L
2% of EPA limit
Gross Alpha Radiation5.8 / 15 pCi/L
39% of EPA limit
8% of EPA limit
2% of EPA limit
Atrazine0.012 / 3 ug/L
0% of EPA limit
Nickel0.0021 mg/L
UnregulatedInorganic
Fluoride0.96 / 4 mg/L
24% of EPA limit
Antimony0.001 / 0.006 mg/L
17% of EPA limit
Barium0.035 / 2 mg/L
2% of EPA limit
PFAS (tested — none detected)
Microplastics (not routinely tested)

Other cities in Green County

Water quality reports for nearby Wisconsin communities.

Frequently asked questions

Is Monticello, WI tap water safe to drink?
Monticello tap water meets EPA legal standards (Maximum Contaminant Levels). However, 3 contaminants are present above independent health guidelines, which are often stricter than legal limits. 15 contaminants have been detected in the water supply, including Lead, Nitrate, Arsenic, Copper, Radon. 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 Monticello water?
Monitoring has detected 15 contaminants in Monticello's water supply: Lead, Nitrate, Arsenic, Copper, Radon, Radium, Uranium, Gross Alpha Radiation, Total Trihalomethanes, Haloacetic Acids (HAA5), Atrazine, Nickel, Fluoride, Antimony, Barium. 3 exceed health guidelines. See individual system reports for concentrations relative to EPA limits.
Does Monticello water have PFAS?
Monticello's water has been tested for PFAS compounds with no detections. Testing was conducted as part of the EPA's Unregulated Contaminant Monitoring Rule (UCMR5) program.
Is Monticello water hard?
Yes. Monticello water has a hardness of 360 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 Monticello get its drinking water?
Monticello's drinking water comes from groundwater wells that draw from underground aquifers. The water is treated and tested according to Wisconsin DNR and EPA requirements before distribution. Monticello is served by one water system: MONTICELLO WATERWORKS.

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