|Rocky Gorge Reservoir|
|Primary inflows||Patuxent River|
|Primary outflows||Patuxent River|
|Catchment area||132 sq mi (340 km2)|
|Basin countries||United States|
|Surface area||773 acres (313 ha)|
|Average depth||74 ft (23 m)|
|Water volume||5,500,000,000 US gal (0.021 km3)|
Rocky Gorge Reservoir is located on the Patuxent River in Howard County, Montgomery County and Prince George’s County, Maryland near the town of Burtonsville. The reservoir was created in 1952 by the construction of the T. Howard Duckett Dam on the Patuxent. The dam is visible from Interstate 95 near mile marker 34. Because of its close association with a dam by the name, the reservoir is sometimes called the T. Howard Duckett Reservoir. It has a surface area of 773 acres. The reservoir is maintained as a drinking water source by the Washington Suburban Sanitary Commission (WSSC).
WSSC provides recreational facilities to the public on portions of the Rocky Gorge property, including hiking, picnicing, fishing, boating, horseback riding, and hunting. Local fish species include pike and largemouth bass.