West Ridge Water Hardness & Quality Report (2026)

West Ridge is a neighborhood within Chicago, Illinois, served by the Chicago Department of Water Management (CDWM), which supplies over 5 million residents across Cook County and surrounding areas. Water originates from Lake Michigan via two major intake cribs in the lake, treated at the Jardine Water Purification Plant (1 billion gallons/day capacity) and the South Water Purification Plant. No local groundwater wells are used; the supply is purely Lake Michigan sourced. Treatment includes screening, chemical coagulation, sedimentation, dual-media filtration, ozonation, and chloramination.

The supply draws from the Lake Michigan watershed within the Great Lakes Basin, bordered by glacial till plains and Paleozoic bedrock of Ordovician Maquoketa Group shales, Silurian dolomites, and dolomitic limestones. These carbonate-rich formations dissolve to release calcium and magnesium ions, shaping a hard supply character. Glacial deposits from the Wisconsinan glaciation overlay the basin, influencing sediment load and mineral leaching into the lake. The limestone-dolomite geology naturally mineralises the water, contributing to its hardness without reliance on deep aquifers.

Hard water leads to moderate scale buildup in pipes, heaters, and fixtures, most affecting water heaters, dishwashers, washing machines, and coffee makers, where efficiency drops and energy use rises 20–30%. Soap lathering diminishes, leaving films on dishes and skin. Maintenance includes annual descaling of appliances, vinegar soaks for showerheads, and installing sediment filters. A water softener is recommended to mitigate scale, extend appliance life, and improve cleaning efficacy. Chicago's water maintains pH 7.5–8.5, compliant with EPA standards; the lead action level was met at schools including West Ridge per the 2024 CPS report, and no PFAS exceedances have been reported in recent CCRs.