East Moline Water Hardness & Quality Report (2026)

East Moline, Illinois, in Rock Island County — one of the Quad Cities (Rock Island, Moline, Davenport, Bettendorf) on the Mississippi River, an industrial city with deep John Deere and agricultural equipment manufacturing heritage — receives its municipal water from the East Moline Water Division or Illinois American Water, which draws from the Mississippi River at the Rock Island-Moline reach. The Quad Cities municipalities share the Upper Mississippi River as their primary water supply.

The hard 206.5 mg/L hardness and elevated TDS of 452.7 mg/L reflect the Upper Mississippi River's substantial carbonate mineral loading in the Quad Cities reach. The Mississippi River above Rock Island County drains the Driftless Area and the upper Midwest carbonate platform — the Silurian Galena-Platteville Dolomite (the rock unit responsible for the region's famous lead mines and for prolific carbonate spring baseflow), the Ordovician Prairie du Chien Group, and the Silurian Niagaran carbonate group. The Mississippi River's consistent carbonate-rich baseflow from Wisconsin's dolomite springs and the drainage from the Upper Midwest Devonian limestone platform produces consistently hard finished water in the Quad Cities municipal supply zone after conventional treatment.

At 206.5 mg/L, East Moline's water is hard — scale builds in kettles and appliances within weeks, dishwashers require rinse aid or softener salt, and bathroom fixtures develop calcium deposits. Monthly descaling of heating appliances is practical. A water softener is recommended for East Moline households. The PFAS level of 7.2 ppt warrants a certified drinking water filter — the Quad Cities' John Deere and industrial manufacturing legacy, the Rock Island Arsenal (federal armament manufacturing on Arsenal Island), and the Upper Mississippi River industrial corridor's PFAS discharge history all contribute to the Rock Island County supply's PFAS background.