Inver Grove Heights Water Hardness & Quality Report (2026)

The Inver Grove Heights Utilities Division manages the public water supply for the city of Inver Grove Heights in Dakota County, Minnesota, serving approximately 22,000 residents across the city limits. Water is sourced exclusively from groundwater wells tapping the Mount Simon-Hinckley aquifer system. The city operates multiple wells with on-site treatment facilities employing filtration and chlorination; there are no surface water treatment plants. Contact the Utilities Division at 651-450-4309 or water@ighmn.gov for inquiries within the Twin Cities southern suburbs service area.

The supply originates from the Mount Simon-Hinckley aquifer, part of Cambrian sandstone formations underlying east-central Minnesota, recharged slowly via precipitation infiltrating glacial till and bedrock fractures in the Upper Mississippi River Basin. The geology features carbonate-rich layers interbedded with sandstones — including the Jordan and Oneota formations — which dissolve over time to release minerals into the groundwater. This prolonged rock-water interaction beneath overlying glacial drift and Quaternary sediments imparts a naturally very hard character to the supply at 370 mg/L.

At very hard levels (370 mg/L), scale buildup is severe, rapidly coating pipes, water heaters, dishwashers, and washing machines — water heaters may fail 2–3 times faster without mitigation. Faucets and fixtures develop stubborn white deposits, and laundry feels stiff. Annual descaling, sediment pre-filters, and vinegar soaks help manage buildup; a whole-house water softener is strongly recommended. pH measures 7.7; iron undetectable at 0.00 mg/L, manganese at 0.02 mg/L, sodium at 4.4 mg/L; the utility reports 5 contaminants above EPA health guidelines, including an MCL violation; filtration and chlorine disinfection are applied.