Glendale Heights Water Hardness & Quality Report (2026)

The Village of Glendale Heights Public Water System serves approximately 34,208 residents in DuPage County, Illinois. Water is purchased as surface water primarily sourced from Lake Michigan via the City of Chicago's distribution system. No local treatment plants are operated; the utility relies on purchased finished water with no additional treatment or disinfection applied on-site. Contact the utility at 630-260-6040 or 1615 Glen Ellyn Rd., Glendale Heights, IL 60139.

The supply originates from the Lake Michigan watershed, a massive basin spanning multiple states with inflows from rivers draining forested and agricultural lands. Underlying geology features Paleozoic-era sedimentary rocks — dolomite and limestone formations of the Ordovician and Silurian periods — prevalent around the Great Lakes. These soluble carbonate rocks naturally impart minerals to the water, producing a hard supply character. Glacial deposits from the Pleistocene era overlie the bedrock, adding to mineral content without dilution.

Very hard water causes significant scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan. White deposits on fixtures and soap scum are common, requiring more detergent for cleaning. Regular deliming of appliances and flushing of hot water systems is advised; a water softener is strongly recommended to protect plumbing. The 2021 Consumer Confidence Report notes compliance under Illinois EPA's SWAP program; tapwaterdata.com reports 15+ contaminants tested with 2 above EPA health-based MCLGs. Treatment is handled upstream by Chicago, delivering disinfected surface water.