Oakdale Water Hardness & Quality Report (2026)

Oakdale, Minnesota, in Washington County — a major east Twin Cities suburban community (Oakdale is a significant Washington County city — an east St. Paul suburban community in the I-694 and I-94 east corridor adjacent to Woodbury and Lake Elmo; Oakdale has grown steadily as part of the east Twin Cities suburban belt's expansion; Oakdale is home of the Oakdale Nature Preserve and a network of natural area parks that are characteristic of the Washington County approach to preserving natural wetlands and oak savanna landscapes within the suburban development), a diverse Washington County community with a primarily middle-class suburban family and professional population, adjacent to Woodbury and Maplewood in the east Washington County corridor, home of a significant east Twin Cities retail corridor along I-94, and a growing east St. Paul suburban community — draws its municipal water supply from the Prairie du Chien–Jordan Aquifer via the City of Oakdale Water Division. Water hardness in Oakdale measures 181 mg/L — classified as hard.

Oakdale's hard supply reflects the east Twin Cities Washington County Paleozoic Platform aquifer's calcareous character. The Prairie du Chien–Jordan Aquifer at Oakdale draws from the Cambrian Jordan Sandstone (calcareous) and Ordovician Prairie du Chien Dolomite (calcareous). City of Oakdale applies limited softening, producing the hard 181 mg/L.

At 181 mg/L, Oakdale residents face regular hard water challenges. Monthly descaling and water softeners are recommended. City of Oakdale Water Division consistently delivers water meeting all Minnesota PCA and EPA Safe Drinking Water Act requirements.