Inver Grove Heights Water Hardness & Quality Report (2026)

Inver Grove Heights, Minnesota, in Dakota County — a major south Dakota County suburban community (Inver Grove Heights is the most populous city in Dakota County — a significant south Twin Cities suburban community in the rapidly growing Dakota County corridor along the Mississippi River), home of Inver Hills Community College (a significant south metro community college serving Dakota County and surrounding communities), adjacent to Pig's Eye Lake (a major Mississippi River oxbow lake and wildlife area in the south St. Paul–Inver Grove Heights area), a rapidly growing Dakota County community with a significant Native American, Vietnamese-American, and working-class professional population, and a Mississippi River bluffs community with notable natural scenery — draws its municipal water supply from the deep Cambrian–Ordovician aquifer via the City of Inver Grove Heights Water Division. Water hardness in Inver Grove Heights measures 112 mg/L — classified as moderately hard.

Inver Grove Heights's moderate hardness — significantly softer than nearby Roseville (284 mg/L) and Cottage Grove (199 mg/L) — reflects effective lime softening by the City of Inver Grove Heights of the same Paleozoic carbonate aquifer. The Prairie du Chien Dolomite and Jordan Sandstone at Inver Grove Heights draws from the same highly calcareous Ordovician–Cambrian aquifer (raw hardness typically 300–400 mg/L). City of Inver Grove Heights applies more aggressive lime softening, producing the moderate 112 mg/L.

At 112 mg/L, Inver Grove Heights residents encounter moderate scale accumulation. Monthly cleaning with citric acid solution is recommended. City of Inver Grove Heights Water Division consistently delivers water meeting all Minnesota PCA and EPA Safe Drinking Water Act requirements.