Maplewood Water Hardness & Quality Report (2026)

Maplewood, Minnesota, in Ramsey County adjacent to Saint Paul — a major Saint Paul east suburban community, home of 3M Company's global headquarters (one of the world's largest manufacturing companies, founded as Minnesota Mining and Manufacturing Company, headquartered in Maplewood since 1902), the Mall of America's smaller predecessor (Maplewood Mall, one of the largest malls in the Twin Cities), and a diverse Ramsey County community with significant Hmong-American, Somali-American, and Latin American populations — draws its municipal water supply from St. Paul Regional Water Services (SPRWS) or local groundwater via the City of Maplewood Water Division. Water hardness in Maplewood measures 113.5 mg/L — classified as moderately hard.

Maplewood's moderate hardness reflects the east Twin Cities Ramsey County calcareous geology and SPRWS supply. The SPRWS Mississippi River supply (from the Mississippi River in the St. Paul area — the Ordovician Prairie du Chien Dolomite and Cambrian Jordan Sandstone calcareous-moderate aquifer zone) and local Prairie du Chien–Jordan Aquifer wells provide water moderately affected by the highly calcareous Twin Cities Paleozoic carbonate sequence. The effective SPRWS treatment and Maplewood's distribution produce the moderate 113.5 mg/L.

At 113.5 mg/L, Maplewood residents encounter moderate scale accumulation. Monthly cleaning with citric acid solution is recommended. City of Maplewood Water Division consistently delivers water meeting all Minnesota MDH and EPA Safe Drinking Water Act requirements.