Baldwin Water Hardness & Quality Report (2026)

Baldwin, Pennsylvania, in Allegheny County — a large township in the South Hills of Allegheny County immediately south of Pittsburgh, one of the most populous suburban townships in western Pennsylvania — receives its municipal water from Pennsylvania American Water (PAWC) or the Allegheny County municipal water system, which draws from the Monongahela River or local tributaries in the south Allegheny County corridor, serving the South Hills municipalities.

The moderately hard 127.5 mg/L hardness and TDS of 244.6 mg/L are softer than the West Mifflin reading (189 mg/L, TDS 465) — reflecting that Baldwin's service area may use a different treatment plant or source blend in the South Hills. The Monongahela River supply is treated at the McKeesport Water Treatment Plant or similar PAWC facilities, producing moderately hard water from the Appalachian Plateau Pennsylvanian carbonate drainage (Pittsburgh Coal Measures — Allegheny Group and Conemaugh Group calcareous shale and limestone).

At 127.5 mg/L, Baldwin'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 6.7 ppt warrants a certified drinking water filter — the US Steel Pittsburgh corridor (Mon Valley industrial legacy), the Allegheny County manufacturing belt (south Pittsburgh industrial zone), and the western Pennsylvania defense-aerospace PFAS complex contribute to Baldwin's PFAS readings.