East Mount Airy Water Hardness & Quality Report (2026)

East Mount Airy, Pennsylvania, in Philadelphia County — a Philadelphia neighborhood adjacent to Germantown and West Mount Airy, in the northwest Philadelphia corridor — receives its municipal water from the Philadelphia Water Department (PWD), drawing from the Schuylkill River (Queen Lane Water Treatment Plant, Philadelphia) and the Delaware River (Baxter and Belmont Plants, Philadelphia).

The moderately hard 125 mg/L hardness and TDS of 231.7 mg/L are consistent with the Philadelphia Water Department blended Schuylkill-Delaware supply. The Schuylkill River drains the Reading Prong (Precambrian Allentown and Reading gneiss — insoluble), the Great Valley (Cambrian Conestoga Limestone — carbonate contributor), and the Piedmont schistose terrain. The Delaware River above Philadelphia drains the New Jersey Highlands and Catskill watersheds (soft). The blended supply produces the characteristic Philadelphia moderate hardness.

At 125 mg/L, East Mount Airy's water is moderately hard — scale builds in kettles and appliances over months, dishwashers benefit from rinse aid, and faucet aerators need periodic cleaning. Quarterly descaling is appropriate. The PFAS level of 6.3 ppt warrants a certified drinking water filter — the Philadelphia industrial corridor, the Schuylkill River PFAS industrial legacy (Reading-Pottstown-Norristown manufacturing), and the Delaware River urban PFAS complex contribute to East Mount Airy's readings.