Kennedy Street Water Hardness & Quality Report (2026)

DC Water supplies Kennedy Street and the District of Columbia with drinking water for over 700,000 residents. The sole source is the Potomac River, drawn from intakes at Great Falls and Little Falls. These waters are purified at the Washington Aqueduct's Dalecarlia and Fort Reno plants, facilities managed by the U.S. Army Corps of Engineers. After treatment, the water travels through an extensive network of 1,300 miles of pipes to reach every corner of the city.

The watershed's geology, particularly the Piedmont region upstream, is key to the water's character. Ancient metamorphic and igneous rocks, including the Loudoun Formation (schist and quartzite) and Mather Gorge Formation (granitic gneiss), are weathered by the river. This natural process releases alkaline earth metals like calcium and magnesium into the water, resulting in its moderately mineralized, moderately hard quality. Unlike some regions, no groundwater aquifers contribute to the supply; the water chemistry is primarily dictated by the river's flow over this rocky terrain.

Homeowners might notice moderate scale buildup in appliances like dishwashers and water heaters, along with soap scum in showers and occasional spotting on glassware. Kettles and coffee makers can also accumulate deposits, potentially affecting their efficiency. To combat these effects and prolong appliance life, regular descaling with vinegar, using detergent boosters, or installing a whole-house water softener are effective strategies. DC Water also provides free lead testing kits, and their latest consumer confidence report indicates all regulated contaminants are well below EPA limits.