[4] The lake covers approximately 4,000 acres (16 km2) of water and 45 mi (72 km) of shoreline.

Fort Cobb Reservoir has a total capacity of 143,740 acre-feet (177,300,000 m3) and covers an area of 5,956 acres (24.10 km2) at top of flood pool level.

The Fort Cobb Reservoir is part of the Washita Basin Project of the Bureau of Reclamation, which also includes Foss Reservoir on the Washita River in Custer County, along with numerous small flood-control structures on creeks and streams.

The primary fish species include white and smallmouth bass, channel catfish, walleye, bluegill, bullhead, saugeye and crappie.

Fort Cobb State Park and the wildlife management areas of the lake.