USS Chimo, a single-turreted, twin-screw monitor, was built by the Aquila Adams, South Boston, MA, and launched 5 May 1864, and commissioned 20 January 1865, Acting Master John C. Dutch in command. Chimo was a Casco-class, light-draft monitor intended for service in the shallow bays, rivers, and inlets of the Confederacy. These warships sacrificed armor plate for a shallow draft and were fitted with a ballast compartment designed to lower them in the water during battle.