Woodbury Water Hardness & Quality Report (2026)

Woodbury, Minnesota, in Washington County southeast of St. Paul — consistently ranked among the best places to live in Minnesota and one of the Twin Cities' fastest-growing suburban communities — draws its municipal water supply exclusively from deep bedrock groundwater wells via the City of Woodbury Public Works Water Division, accessing the Jordan Sandstone (Upper Cambrian) and the Prairie du Chien Group (Lower Ordovician — including the Oneota Dolomite and New Richmond Sandstone) aquifer system beneath Washington County. Water hardness in Woodbury measures 220.5 mg/L — classified as very hard.

Woodbury's very hard supply reflects the Prairie du Chien Group dolomite aquifer's high carbonate reactivity. The Prairie du Chien Group — the Oneota Dolomite and New Richmond Sandstone (Lower Ordovician) — is one of the most calcareous and reactive dolomite formations in the upper Midwest. Unlike Plymouth and Maple Grove (which blend Minneapolis Mississippi River surface water with some groundwater), Woodbury relies entirely on deep bedrock groundwater from the Prairie du Chien Dolomite, which has unlimited contact time with the reactive dolomite ($CaMg(CO_3)_2$) matrix. The very hard 220.5 mg/L reflects unblended deep dolomite groundwater — characteristic of southeast metro Twin Cities communities relying solely on deep bedrock wells.

At 220.5 mg/L, Woodbury residents face significant hard water challenges. Scale deposits form rapidly on faucet aerators, showerheads, shower glass, and tile — monthly descaling with citric acid solution is essential maintenance. City of Woodbury Public Works Water Division consistently delivers water meeting all Minnesota MDH and EPA Safe Drinking Water Act requirements.