Moorhead Water Hardness & Quality Report (2026)

Moorhead, Minnesota, the Clay County seat across the Red River from Fargo, North Dakota — a major Minnesota–North Dakota border city, home of Minnesota State University Moorhead (MSUM), Concordia College, and Minnesota State Community and Technical College, a significant Scandinavian-American (Norwegian, Swedish, and Danish) heritage community, the Minnesota twin city to Fargo in the Red River Valley — draws its municipal water supply from the Red River of the North via the City of Moorhead Water Division. Water hardness in Moorhead measures 240 mg/L — classified as very hard.

Moorhead's very hard supply reflects the Red River Valley's extreme calcareous Lake Agassiz geology. The Red River of the North drains through: the Lake Agassiz basin — the former bed of Glacial Lake Agassiz (the largest glacial lake in North American history, which covered most of Manitoba, North Dakota, and northwest Minnesota); the Cretaceous Pierre Shale (highly calcareous marine shale of the Great Plains Cretaceous Interior Seaway — a major calcium and magnesium dissolution zone); the Quaternary Lake Agassiz lacustrine clay and calcareous marl (highly calcareous lakebed deposits). The calcareous Lake Agassiz lakebed terrain and Pierre Shale produce the very hard 240 mg/L at Moorhead.

At 240 mg/L, Moorhead residents face severe hard water challenges. Weekly descaling and appliance protection measures are strongly recommended. City of Moorhead Water Division consistently delivers water meeting all Minnesota MDH and EPA Safe Drinking Water Act requirements.