Mokena Water Hardness & Quality Report (2026)

The Mokena Water Company, operated by the Village of Mokena, serves approximately 17,674 residents in Mokena, Illinois, located in Will County. Water is sourced from purchased surface water, likely from regional providers supplying the broader Chicago metropolitan area. Annual Consumer Confidence Reports are published on the village website at mokena.org, with the 2024 report available as a PDF; the utility is contactable at 11004 Carpenter Street, Mokena, IL 60448 (708-479-3900; administration@mokena.org).

The supply draws from surface watersheds in the Des Plaines River basin, shaped by glacial geology and underlying Paleozoic carbonate formations including Silurian-age dolomite and limestone from the Niagaran Series. These carbonate-rich rocks weather to release dissolved minerals, yielding a hard supply common to Illinois surface waters that retain significant mineral content from the limestone-dominated terrain even after clarification and chlorination. The glacial till plains of the Chicago region concentrate calcium and magnesium, producing characteristically hard water across northeastern Illinois sources.

Very hard water promotes significant scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan — hot water systems and fixtures show white deposits most prominently. Regular deliming of appliances and flushing of heaters is advised; a water softener is strongly recommended to mitigate soap inefficiency and spotting on glassware. Village reports note fluoride adjusted to 0.7 mg/L (range 0.6–0.8 mg/L) and sodium presence. Contaminants flagged in alerts include Di(2-ethylhexyl) adipate, trans-1,2-Dichloroethylene, lead, and 1,1-Dichloroethane; treatment involves standard clarification and chlorination — check the latest CCR for current lead/copper tap results and PFAS data.