Sudbury Water Hardness & Quality Report (2026)

Sudbury Water District serves approximately 18,620 residents in Sudbury, Massachusetts (Middlesex County). The utility operates a groundwater-based system drawing from at least two production wells — Well #2 and Well #9 — located at the district's office building at 199 Raymond Road. Treatment includes chloramination as the primary disinfection method, and the district publishes annual Water Quality Reports; the 2024 report is currently available online. The utility recommends flushing faucets for 30 seconds to 2 minutes after periods of stagnation to minimize potential lead exposure from service lines.

The supply originates from groundwater in the New England Upland physiographic province, where bedrock consists of Precambrian metamorphic and igneous rocks typical of eastern Massachusetts. The glacially-derived aquifer is heavily mineralized due to natural dissolution of carbonate and silicate minerals in the bedrock and glacial deposits. This geological setting produces water with very high mineral content, particularly dissolved calcium and magnesium, making the supply characteristically very hard.

At very hard water levels, white calcium deposits accumulate on fixtures and in hot water tanks, and scale buildup occurs in water heaters and appliances, while soap and detergent efficiency is reduced. The district recommends maintaining hot water tank thermostats below 130 °F to minimize calcium precipitation. Many households benefit from point-of-use or whole-house water softening. Iron and manganese minerals in the water can cause staining, particularly in homes with copper plumbing. The 2024 Water Quality Report documents compliance with Safe Drinking Water Act standards.