South Lawndale Water Hardness & Quality Report (2026)

South Lawndale, a community area in Chicago, Illinois, is served by the Chicago Department of Water Management (CDWM), which supplies water to over 5 million people across Cook County and surrounding areas. The primary source is Lake Michigan, drawn through two major intake cribs in the lake. Water is treated at the Jardine Water Purification Plant (capacity 1.04 billion gallons per day) and the South Water Purification Plant, then distributed through extensive underground mains to the 60623 ZIP code area and beyond.

Lake Michigan forms the watershed, part of the binational Great Lakes system. Underlying geology features Paleozoic carbonate formations, notably Silurian-age dolomites and limestones of the Racine and Waukegan Formations prevalent in northeastern Illinois, with surficial glacial deposits from the Wisconsinan glaciation overlying deeper shales. These carbonate rocks dissolve to impart minerals; the hard supply character arises from interaction with limestone and dolomite layers during sourcing, treatment, and conveyance through mineral-reactive infrastructure, typical of the Chicago region.

Hard water leads to scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan; faucets and fixtures show white deposits, and soap lathering is poor, increasing detergent use. Annual deliming of heaters and sediment filters are recommended; a water softener is advised to protect appliances. Chicago water typically has pH 7.5–8.5 and complies with EPA lead and copper rules via corrosion control. No significant PFAS exceedances are reported in recent CCRs; treatment includes screening, ozonation, dual-media filtration, and chloramination, with monitoring for chromium-6 and disinfection byproducts staying under limits.