LaSalle County · 19,288 residents · 7 water systems
8
Contaminants detected
1
PFAS compounds
329
Hardness (mg/L)
3
Above legal limits
4
Above health guidelines
Ottawa drinking water comes from groundwater wells. Based on the most recent monitoring data, 8 contaminants have been detected in the water supply, including Lead, Copper, Radium, Total Trihalomethanes, and 4 others. PFAS compounds have been detected at trace levels in Ottawa water. Water hardness is 329 mg/L (very hard), which can cause scale buildup in appliances and reduce soap effectiveness.
Contaminants detected in Ottawa water
8 total
Detection does not necessarily mean unsafe levels. See individual reports for concentrations and EPA limits.
Ottawa tap water has 3 contaminants currently measured above EPA legal standards (Maximum Contaminant Levels), and 4 above independent health guidelines. 8 contaminants have been detected in the water supply, including Lead, Copper, Radium, Total Trihalomethanes, Haloacetic Acids (HAA5). View the detailed report for each water system to see specific levels, how they compare to both legal limits and health guidelines, and what actions to take.
What contaminants are in Ottawa water?
Monitoring has detected 8 contaminants in Ottawa's water supply: Lead, Copper, Radium, Total Trihalomethanes, Haloacetic Acids (HAA5), Fluoride, Barium, Lithium. Additionally, 1 PFAS compounds have been detected at trace levels. 3 of these are above EPA legal limits. 4 exceed health guidelines. See individual system reports for concentrations relative to EPA limits.
Does Ottawa water have PFAS?
Yes. 1 PFAS compounds have been detected in Ottawa'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 Ottawa water hard?
Yes. Ottawa water has a hardness of 329 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 Ottawa get its drinking water?
Ottawa'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. Ottawa is served by 7 water systems, the largest being OTTAWA (serving 18,097 people).
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