Orland Park Water Hardness & Quality Report (2026)

The Orland Park Water Company serves Orland Park, Illinois, in Cook County, providing drinking water to approximately 56,350 residents across ZIP codes 60462 and 60467. The utility purchases finished surface water from the Village of Oak Lawn, which receives it from the City of Chicago. Chicago's Jardine Water Purification Plant treats raw water drawn from Lake Michigan, delivering it through an extensive distribution network to suburbs including Orland Park. Treatment involves conventional processes including screening, coagulation, sedimentation, filtration, and chlorination at Chicago's plants.

The supply originates from the Lake Michigan watershed, a massive Great Lakes basin spanning multiple states. Paleozoic bedrock formations — including Devonian-era limestones and dolomites — underlie the basin and dissolve to impart a hard character rich in calcium and magnesium. Quaternary glacial deposits from the Pleistocene era further influence mineral leaching into the surface waters, shaping a moderately mineralised profile through regional carbonate dissolution.

Hard water causes scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan. Soap lathering is diminished, often requiring more detergent, and skin may feel drier after bathing. Regular deliming of appliances annually and installing drain screens helps mitigate issues; a water softener is recommended to prevent scaling and extend equipment life. Potential contaminants include haloacetic acids (HAA5), bromodichloromethane, naphthalene, vanadium, and dinoseb, though levels are regulated; pH is typically neutral to slightly alkaline and the supply complies with EPA standards.