Champaign Water Hardness & Quality Report (2026)

Illinois American Water – Champaign District is the public water utility serving Champaign and surrounding areas in Champaign County, Illinois. The system draws groundwater via 19–21 wells primarily in the Mahomet Sands Aquifer. Treated water is produced at two lime softening plants: the Mattis Avenue Plant in Champaign and the Bradley Avenue Plant west of Champaign. The utility distributes water through an extensive network that includes connections to the University of Illinois Urbana-Champaign campus system; lime softening, pH and alkalinity adjustment, and corrosion control are applied per Illinois EPA designation.

The supply originates from the Mahomet Bedrock Valley Aquifer system, specifically the Mahomet Sands — a Pleistocene-age glacial outwash deposit of unconsolidated sand and gravel located in east-central Illinois. Wells range from 208 to 366 feet in depth, protected from surface contamination by overlying geologic barriers assessed as not geologically sensitive by the Illinois Environmental Protection Agency. This aquifer overlies less permeable bedrock formations; dissolution of subsurface limestone and dolomite minerals contributes elevated calcium, magnesium, and bicarbonate, imparting a hard supply character.

At hard levels, users may notice moderate scale buildup on fixtures, reduced soap lathering, and spotty dishes without a rinse aid; water heaters, dishwashers, washing machines, and coffee makers lose efficiency from mineral deposits over time. Regular maintenance such as deliming heaters annually and using rinse aids helps; a water softener is often recommended for households experiencing these issues to extend appliance life and improve cleaning. The utility complies with lead and copper rules via corrosion control designated optimal by the Illinois EPA; eight contaminants exceed health guidelines in some analyses but remain at levels requiring only less frequent sampling.