Westwood Water Hardness & Quality Report (2026)

The Dedham-Westwood Water District supplies drinking water to Westwood and parts of Dedham in Norfolk County, Massachusetts. The utility operates seventeen groundwater wells, with five located in Westwood near the Neponset River by University Avenue and one by Rock Meadow Brook near Dover Road. There are no surface water treatment plants; water is sourced entirely from local aquifers and treated at wellhead facilities before distribution. The service area covers residential, commercial, and institutional users in these communities.

The water originates within the Neponset River Watershed, where glacial deposits form productive sand and gravel aquifers. These unconsolidated sediments, derived from Pleistocene glaciations, overlie crystalline bedrock and contain variable carbonate materials that influence chemistry. The moderately mineralised character stems from interaction with these limy glacial drift layers, dissolving hardness ions while keeping total dissolved solids moderate. No major reservoirs are involved; the supply relies on confined and unconfined aquifer zones recharged by local precipitation and river infiltration.

Moderately hard water promotes moderate scale buildup in appliances like water heaters, dishwashers, and coffee makers, reducing efficiency over time. Laundry may feel stiffer, and soap lathering is somewhat reduced. Regular maintenance includes deliming fixtures annually and flushing water heaters. A water softener is often recommended for households with hard water concerns to extend appliance life and improve cleaning, especially if spotting on dishes or film on skin is noticed. DWWD reports full compliance with EPA standards, including lead and copper rule (90th percentile copper 0.22 mg/L, lead below action level). No PFAS detections above limits noted in recent CCRs. Treatment includes disinfection (chlorine), corrosion control, and wellhead filtration; groundwater inherently low in organics. Surface waters like Neponset River face recreational issues with E.coli and phosphorus, but drinking supply is separate and high-quality. pH typically 7.0-8.0.