Lewiston Water Hardness & Quality Report (2026)

Lewiston, Maine, in Androscoggin County — a major west Maine city paired with Auburn (Lewiston-Auburn — known collectively as 'L-A' — form the second-largest metropolitan area in Maine, twin cities on opposite banks of the Androscoggin River), a historic textile and mill city (Lewiston was the center of Maine's Franco-American textile industry in the late 19th and early 20th centuries — one of the largest concentrations of French-Canadian immigrant mill workers in New England), now home of Bates College (a prestigious liberal arts college in Lewiston, one of the 'Three Maine Colleges' alongside Bowdoin and Colby), and a diverse community known for its large Somali-American immigrant population (Lewiston has one of the highest concentrations of Somali-Americans in New England, having received significant immigration since the early 2000s) — draws its municipal water supply from the Androscoggin River via the LAWPCA. Water hardness in Lewiston measures 18 mg/L — classified as very soft.

Lewiston's exceptionally soft supply reflects the Androscoggin River watershed's highly calcareous-poor Maine Appalachian crystalline geology. The Androscoggin River at Lewiston drains: the Maine Appalachian Mountains (Proterozoic–Paleozoic calcareous-poor gneiss, schist, and granodiorite — the highly resistant crystalline Maine Appalachian basement with essentially no dissolved calcium carbonate); and the White Mountain granite (calcareous-poor). The highly calcareous-poor Maine crystalline watershed produces the exceptional 18 mg/L.

With hardness at 18 mg/L, Lewiston residents enjoy exceptionally soft water. LAWPCA consistently delivers water meeting all Maine DEP and EPA Safe Drinking Water Act requirements.