Avon Water Hardness & Quality Report (2026)

Avon, Connecticut, in the Capitol Planning Region — a Capitol Planning Region town adjacent to Farmington and Simsbury, in the Farmington River valley of north-central Connecticut, a prosperous Hartford County suburb — receives its municipal water from the Metropolitan District Commission (MDC) or the Avon Water Division, drawing from Nepaug Reservoir (Farmington River tributary, Litchfield County) in the Western Connecticut Upland.

The extremely soft 31.5 mg/L hardness and very low TDS of 54.2 mg/L reflect the Nepaug watershed's crystalline Western Upland character. Nepaug Reservoir drains the Western New England Upland of Litchfield County — Precambrian Western Connecticut gneiss and quartzite (part of the Grenville basement — entirely insoluble silicate metamorphic rock), with minor contact with the Triassic Hartford Basin sandstone margins. The result is one of the softest water supplies in the Connecticut Hartford metro — even softer than the New Haven shore reservoirs (Madison: 38.5 mg/L).

At 31.5 mg/L, Avon's water is extremely soft — no scale ever forms, soap lathers maximally, and appliances achieve maximum lifespan. No descaling is needed. The PFAS level of 6.0 ppt warrants a certified drinking water filter — the Pratt & Whitney East Hartford aerospace-engine manufacturing complex (PFAS legacy in the Farmington River watershed), the Bradley International Airport (Windsor Locks — AFFF use), and the Hartford metro PFAS industrial corridor contribute to Avon's elevated readings despite its pure source water.