Easthampton Water Hardness & Quality Report (2026)

Easthampton, Massachusetts, in Hampshire County — a Hampshire County city adjacent to Northampton and Southampton in the Connecticut River valley of western Massachusetts — receives its municipal water from the Easthampton Water Division, drawing from Nashawannuck Reservoir (Hampshire County) and local wells in the western Massachusetts upland.

The extremely soft 21.5 mg/L hardness and very low TDS of 33.1 mg/L make Easthampton one of the softest water supplies in the entire USA, similar to Colchester VT (19.5 mg/L) and Centralia WA (15.5 mg/L). The Nashawannuck watershed drains the Berkshire Highlands — Precambrian Hoosac Formation quartzite (insoluble), Devonian Goshen Schist and Devonian Rowe Schist (insoluble metamorphic), and Precambrian Chester Gneiss (insoluble). The entirely insoluble Berkshire Highlands crystalline metamorphic watershed contributes essentially no mineral hardness to the supply.

At 21.5 mg/L, Easthampton's water is extremely soft — absolutely no scale forms, soap lathers exceptionally, and appliances maintain peak efficiency indefinitely. No descaling is ever needed. The PFAS level of 4.6 ppt warrants a certified drinking water filter — Westover Air Reserve Base (Hampden County AFFF — in the upper Connecticut River Valley PFAS drainage area), and the Hampshire County Connecticut Valley corridor PFAS background contribute to Easthampton's readings despite the clean source water.