Park Forest Water Hardness & Quality Report (2026)

The Park Forest water utility, operated by the Village of Park Forest Public Works Department in Park Forest, Cook County, Illinois, serves approximately 21,975 residents. Water is sourced exclusively from groundwater via six wells tapping a dolomite limestone aquifer at depths of 300–340 feet; treatment involves conventional softening and disinfection with hypochlorite. Annual Water Quality Reports are available at villageofparkforest.com/300/Water-Quality-Reports and vopfwaterreport.com; the utility can be reached at 708-283-5602 or 708-503-7702.

Park Forest's groundwater originates from a dolomite limestone aquifer in the region's Paleozoic bedrock, part of the broader Illinois Basin karst system. The geology features dolomite — a magnesium-rich carbonate rock (calcium magnesium carbonate) — that naturally mineralizes infiltrating rainwater, producing a very hard supply with elevated dissolved solids from prolonged rock–water contact. The Illinois Environmental Protection Act enforces a minimum 400-foot protection zone around each well to safeguard this aquifer from surface contamination.

Very hard water accelerates scale buildup in pipes, water heaters, dishwashers, and washing machines — hot water appliances suffer most due to mineral precipitation at higher temperatures. White deposits on fixtures and laundry stiffness are common. Maintenance includes regular vinegar descaling, installing scale-inhibiting filters, and flushing water heaters biannually; a whole-house water softener is strongly recommended. The utility reports 3 contaminants above EPA health-based guidelines in at least one service area, with 1 MCL violation on record; lead ranged 0–11 ppb and copper 0.031–0.49 ppm; treatment includes conventional filtration, softening, and hypochlorite disinfection.