Oxon Hill Water Hardness & Quality Report (2026)

WSSC Water (Washington Suburban Sanitary Commission) serves Oxon Hill, Maryland, providing water to Prince George's County and surrounding areas. The utility draws from two primary sources: the Potomac River and the Patuxent River, treating water at multiple treatment plants before distribution to residential, commercial, and industrial customers. Treatment employs conventional processes including coagulation, sedimentation, filtration, and chlorination. WSSC Water conducts over 500,000 water quality tests annually, making it one of the most rigorously monitored utilities in the region.

The Potomac River watershed dominates regional hydrology, flowing through the Piedmont physiographic province of Maryland. The underlying geology consists primarily of Precambrian metamorphic rocks — gneiss, schist, and granite — overlain by Paleozoic sedimentary formations including limestone and dolomite. These carbonate-rich formations dissolve into groundwater and surface water as precipitation percolates through soil and rock, contributing dissolved minerals — particularly calcium and magnesium — that produce a moderately hard to hard water supply character.

Oxon Hill's water is classified as hard, making scale buildup in pipes, water heaters, and appliances a common concern. Residents may notice reduced lather from soap, spotting on dishes and glassware, and mineral deposits on fixtures. Water softening is recommended, particularly for households with high usage or sensitive appliances; regular descaling of water heaters and fixtures helps mitigate effects. Recent quality data notes 2 contaminants above EPA MCLGs, though all federal legal limits (MCLs) are met. WSSC Water monitors continuously and reports full compliance with all state and federal regulations.