Port Washington Water Hardness & Quality Report (2026)

The Port Washington Water District supplies water to about 20,000 residents in the Village of Port Washington and Sands Point in Nassau County, New York. All of its water comes from local groundwater wells that draw from the Upper Glacial and Magothy aquifers deep beneath Long Island. Each well site treats the water, adjusting the pH with sodium hydroxide and disinfecting it with calcium hypochlorite before it enters the distribution system. The district does not use surface water sources or add fluoride. Detailed testing results are available in their yearly Drinking Water Quality Report.

This supply originates from the Northern Atlantic Coastal Plain aquifer system, specifically within Nassau County. As water filters through the Pleistocene glacial outwash sands and gravels, it interacts with the sandy clays of the underlying Miocene Magothy Formation. This geological journey results in naturally harder water, as minerals dissolve from the glacial deposits and sedimentary layers. This contrasts with water sources that rely solely on precipitation, which tend to be softer.

Homeowners may notice a moderate amount of scale buildup in appliances such as dishwashers, washing machines, and water heaters, which can reduce their efficiency over time and cause spotting on glassware. Coffee makers and boilers might need more frequent descaling. To combat scale, regular vinegar rinses for kettles can help. Installing drain screens can catch sediment, and using detergent boosters for laundry might be beneficial. Installing a water softener is often recommended to prevent spotting, extend appliance lifespan, and improve soap's lathering ability.