H Street NE Water Hardness & Quality Report (2026)

H Street NE, District of Columbia — a vibrant northeast Washington DC neighborhood anchored by the historic H Street Corridor (Atlas District), one of DC's most dynamic urban revival corridors with diverse restaurants, music venues, and the Lincoln Theatre legacy — receives its municipal water from DC Water (District of Columbia Water and Sewer Authority), which draws from the Potomac River through the Washington Aqueduct operated by the US Army Corps of Engineers at the McMillan and Dalecarlia treatment plants. The entire District of Columbia receives the same Washington Aqueduct Potomac River supply.

The moderately hard 113 mg/L hardness and TDS of 253.3 mg/L match precisely the supply profile of other DC neighborhoods (Mount Vernon Triangle: 113 mg/L, TDS 253.4) — confirming that DC Water's distribution system delivers a consistent, well-mixed supply throughout the District with negligible variation by neighborhood or distribution zone. The Potomac River at the DC intakes drains the full complexity of the upper Potomac watershed — Blue Ridge Province (Precambrian Catoctin metabasalt, Harpers Formation phyllite), Valley and Ridge (Ordovician Martinsburg Shale, Helderberg Group limestone), and Piedmont crystalline terrain — producing a moderately hard, mixed-geology supply typical of the major mid-Atlantic river systems.

At 113 mg/L, H Street NE's water is moderately hard — comfortable for all household applications. Scale builds slowly in kettles and appliances over months, dishwashers benefit from rinse aid, and faucet aerators need periodic cleaning. Quarterly descaling of heating appliances is the standard schedule. The PFAS level of 7.5 ppt warrants a certified drinking water filter — DC Water's Potomac River supply faces consistent PFAS pressure from the river's upstream military and industrial sources (Fort Detrick, Marine Corps Base Quantico, Shenandoah Valley industrial discharge), and DC Water operates an active PFAS monitoring and treatment improvement program to manage this ongoing challenge.