Baltimore County relies on surface water from precipitation and meltwater as its main source of water. Three reservoirs outside the city limits collect and store the water, which is managed and protected by the Groundwater Management Section (GWM). The GWM is responsible for dealing with issues related to drinking water wells, on-site wastewater (septic) disposal systems, the disposal of residential underground storage tanks, and the disposal of solid and hazardous waste. The water and wastewater system is owned by the City of Baltimore under state and regional agreements.
It serves 1.8 million residents in the city and county of Baltimore, as well as parts of Howard, Harford, Carroll, and Anne Arundel counties. The Harford County Government, together with citizens and the Maryland Department of Natural Resources, created an action strategy for watershed restoration for the Deer Creek watershed. The Urban Rural Demarcation Line (URDL) separates the areas of the county that receive public water and sewage infrastructure from those that depend on private wells and septic systems. The Baltimore Watershed Agreement formalizes the commitment of the City of Baltimore and Baltimore County to work together to manage and monitor shared watersheds.
This agreement encompasses communities from Upperco to Jacksonville, including Hereford, Parkton, and Cockeysville. Baltimore County is no longer processing new lawsuits for domestic well water pollution that was allegedly caused by the application of salt on roads. In addition, numerous water quality improvement projects have been implemented in this watershed, as well as the dredging of Bird River and Railroad Creek. Olszewski and other county officials have long complained about the city-owned Back River wastewater treatment plant, which is located in Back River, in eastern Baltimore County.
The following are lists of tank removal contractors, water analysis laboratories, septic system installers, well drillers, and asbestos removal contractors that are licensed in Baltimore County. Located just north of the Baltimore Ring Road, this watershed takes up nearly all of central Baltimore County. Located in the northwest corner of Baltimore County, the Prettyboy Reservoir is the second largest and most remote of the area's three watersheds. Middle River is a wide, shallow tidal estuary that extends to the southeast approximately four miles from Eastern Boulevard in Baltimore County before entering Chesapeake Bay.
Loch Raven is the largest of three reservoir basins in the area that, together, provide up to 405 million gallons of water per day to the city and county of Baltimore through Gunpowder Falls. The springs begin in the Greenspring Valley and meander east to Lake Roland, where they merge with eastern tributaries before continuing south across a dam and through Baltimore City. Here they emerge from a tunnel in the Inner Harbor before being treated at Ashburton Water Filtration Plant.