Rosedale Water Hardness & Quality Report (2026)

Rosedale, Maryland, in Baltimore County — an unincorporated Baltimore County community in the east Baltimore County suburban corridor adjacent to Essex and Middle River, part of the east Baltimore County Chesapeake Bay shoreline belt — receives its municipal water from the Baltimore City Department of Public Works through the Baltimore County east distribution system, drawing from the Susquehanna River at Conowingo Reservoir and Loch Raven Reservoir (Gunpowder Falls, north Baltimore County).

The moderately hard 179.5 mg/L hardness and elevated TDS of 446.6 mg/L are harder than expected for Piedmont reservoir supply — reflecting that Baltimore's Conowingo Susquehanna supply is harder than pure Piedmont crystalline water due to the Susquehanna's Great Valley carbonate tributaries (Conestoga River, PA — draining the Lancaster County Ordovician limestone). Loch Raven Reservoir on the Gunpowder Falls collects some Baltimore County Piedmont and Great Valley fringe drainage, also contributing to Baltimore's moderately hard supply throughout the east county distribution zone.

At 179.5 mg/L, Rosedale's water is moderately hard — scale builds in kettles and appliances over months, dishwashers benefit from rinse aid, and bathroom fixtures develop calcium deposits. Quarterly descaling is appropriate. The PFAS level of 9.8 ppt warrants a certified reverse osmosis drinking water filter — Aberdeen Proving Ground (Harford County — Army weapons testing PFAS major site in the Susquehanna watershed), Fort Meade (Anne Arundel County), and the Baltimore industrial port PFAS corridor contribute to Rosedale's elevated readings.