High Quality Content by WIKIPEDIA articles! USS Cohoes — a single-turreted, twin-screw monitor — was still under construction at the close of the American Civil War. She 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.