Water Hardness in Illinois Well Water

In Illinois, water hardness levels average 183.73 mg/L CaCO3, with a maximum recorded level of 356.83 mg/L CaCO3. The EPA limit is 180 mg/L CaCO3. Currently 6.1% of tested wells exceed this limit, affecting approximately 27,450 wells.

Testing for water hardness in Illinois typically costs around $132. If treatment is needed, water treatment systems for water hardness cost approximately $2,730.

The risk level for water hardness in Illinois is rated as low. The state average of 183.73 mg/L CaCO3 is 32.9% above the national average of 138.229 mg/L CaCO3.