Middletown Water Hardness & Quality Report (2026)

Middletown, Connecticut, the Middlesex County seat on the Connecticut River — a major Connecticut River Valley city, home of Wesleyan University (one of the premier liberal arts universities in the United States), the historic Middletown waterfront, a diverse community with significant Puerto Rican and Italian-American populations, and the Connecticut Valley's most significant Connecticut River port city in the colonial and Federal periods — draws its municipal water supply from local reservoir sources via the City of Middletown Water Division. Water hardness in Middletown measures 56.5 mg/L — classified as moderately soft.

Middletown's moderate softness — very soft for a Connecticut River Valley community — reflects the Berkshire Reservoir watershed's calcium-poor New England Upland geology. The Middletown reservoir watersheds drain the Connecticut Eastern Uplands — predominantly Proterozoic and Paleozoic crystalline metamorphic terrain (the Connecticut Eastern Highland — Pennsylvanian–Ordovician gneiss and schist of the Connecticut Eastern Uplands, calcium-poor). The Jurassic Portland Arkose of the Hartford Basin (which underlies central Middletown) contributes modestly to hardness in local Middletown wells, but the reservoir supply from the calcareous-poor upland terrain dominates, producing the moderate 56.5 mg/L at Middletown.

With hardness at 56.5 mg/L, Middletown residents enjoy moderately soft water with minimal scale challenges. City of Middletown Water Division consistently delivers water meeting all Connecticut DEEP and EPA Safe Drinking Water Act requirements.