Prettyboy Reservoir occupies 206.5km2 of northern Baltimore County, Maryland, also known as the Hereford Zone. Even though the reservoir is located in the county, the City of Baltimore owns the reservoir and the surrounding land of forested watershed. The reservoir is one of three reservoirs created to supply the Metropolitan Baltimore municipal water system for Baltimore City, Baltimore County and northern Anne Arundel County constructed by the Baltimore City Department of Public Works. Prettyboy Reservoir, along with Loch Raven Reservoir that is downstream on the Gunpowder Falls, provide about 61% of the drinking water for the entire Baltimore Metropolitan system. For this reason, the Prettyboy is considered a “source water” or drinking water watershed. The reservoir on average contains about 19e9USgal of water.The water from Prettyboy Reservoir is transferred to Loch Raven Reservoir via Gunpowder Falls rather than directly to Baltimore. It is then transferred via tunnel from Loch Raven to the Montebello Filtration Plants in Baltimore for treatment and distribution. Prettyboy Dam, completed in 1932, impounds the Gunpowder Falls to create the Reservoir. The dam has a spillway crest elevation of 520ft of MSL and covers about 1500acre.Prettyboy Reservoir sits behind Prettyboy Dam on the Gunpowder River which flows into the northwestern Chesapeake Bay. The Gunpowder River also serves as a State Park and borderline between Baltimore County and Harford County. The reservoir serves as land for hiking, mountain biking, road cycling, fishing, and boating. Hunting is also permitted, though limited to archery only and requires a special permit. Swimming is officially prohibited. Sport bike riders and sports car enthusiasts also flock to the roads in the parklands that surround the reservoir.
