Ashburn Water Hardness & Quality Report (2026)

Ashburn, Virginia, an unincorporated community in Loudoun County — one of the most economically dynamic communities in Virginia, the 'Data Center Capital of the World' (the Ashburn–Dulles Technology Corridor hosts the world's largest concentration of data centers, processing an estimated 70% of global internet traffic), home of Salesforce, Telos Corporation, and numerous cloud computing companies, a major Northern Virginia tech community adjacent to Dulles International Airport — draws its municipal water supply from Loudoun Water (formerly Loudoun County Sanitation Authority). Water hardness in Ashburn measures 93 mg/L — classified as moderately soft.

Ashburn's moderate softness reflects Loudoun County's mixed watershed geology and Loudoun Water's effective treatment. Loudoun Water's supply comes from the Potomac River and Upper Occoquan Reservoir — the Potomac drains the Blue Ridge and Piedmont (Catoctin Formation metavolcanic greenstone — moderately calcareous volcanic greenstone of the Blue Ridge anticlinorium; Cambrian–Ordovician calcareous dolomite of the Valley and Ridge zone). Loudoun Water applies effective treatment, and the Ashburn area's distribution infrastructure is relatively new (major Ashburn suburban buildout occurred in the 1990s–2010s), producing the moderate 93 mg/L.

With hardness at 93 mg/L, Ashburn residents enjoy moderately soft water. Loudoun Water consistently delivers water meeting all Virginia DEQ and EPA Safe Drinking Water Act requirements.