Marion Water Hardness & Quality Report (2026)

The City of Marion water utility supplies over 17,000 residents in Williamson County, southern Illinois, with groundwater from local aquifers accessed via wells. Water is treated at the city's water treatment plant; the operator Clifford Hogue, Jr. can be reached at 618-993-5533. The Annual Drinking Water Quality Report is available at cityofmarionil.gov. The utility maintains high marks for EPA legal compliance, earning recognition for meeting all enforceable standards, with treatment involving disinfection and basic filtration as documented in annual Consumer Confidence Reports including the 2023 and 2024 CCRs.

The groundwater recharge area encompasses the unglaciated Shawnee Hills region of southern Illinois, feeding confined and unconfined aquifers within the Illinois Basin. Water interacts with Mississippian limestone and dolomite formations along with overlying Pennsylvanian sandstones, which naturally mineralize the supply with dissolved calcium and magnesium. The karst-influenced terrain enhances mineral leaching as water moves through fractures and dissolution channels in these Paleozoic formations, producing a hard supply without softening influences from siliceous rocks.

Very hard water promotes rapid scale buildup in pipes, heaters, and fixtures, leading to reduced efficiency and potential damage to appliances. Hot water heaters, dishwashers, washing machines, and coffee makers suffer most, with white calcium deposits clogging elements and valves. Regular vinegar descaling, installing sediment filters, and using a water softener are recommended to mitigate effects and extend appliance life. Independent health guidelines flag 7 contaminants of concern including TTHMs — bromodichloromethane, chloroform, and bromoform — and radium exceeding advisory levels, though the utility meets all enforceable EPA legal standards.