Cedar Falls Water Hardness & Quality Report (2026)

Cedar Falls, Iowa, in Black Hawk County — the home of the University of Northern Iowa (UNI Panthers, a major Iowa comprehensive university known for education, business, and the Campbell Hall performing arts center), the larger of the Cedar Falls–Waterloo metropolitan area's two cities (though Waterloo is the larger city, Cedar Falls hosts UNI and has a higher per-capita income), and a major northeast Iowa college and professional community — draws its municipal water supply from the Cedar River via the City of Cedar Falls Water Division. Water hardness in Cedar Falls measures 163 mg/L — classified as hard.

Cedar Falls' moderate-to-hard supply reflects the northeast Iowa Cedar River valley's calcareous Devonian and Mississippian geology. The Cedar River at Cedar Falls–Waterloo drains: the Devonian Lime Creek Formation and Iowa Formation (highly calcareous marine limestone and dolomite of the Iowa Paleozoic carbonate sequence); the Mississippian Burlington and Keokuk Formations (calcareous limestone); and Wisconsin Age Des Moines Lobe calcareous till (calcareous glacial deposits from the Des Moines Lobe). The City of Cedar Falls' water treatment plant reduces hardness from the Cedar River supply, producing the moderate 163 mg/L.

At 163 mg/L, Cedar Falls residents face moderate-to-hard scale challenges. Monthly descaling with citric acid solution is standard maintenance. City of Cedar Falls Water Division consistently delivers water meeting all Iowa DNR and EPA Safe Drinking Water Act requirements.