New London Harbor, located in the New London business district, is about three miles upstream from Long Island Sound and about 12 miles west of the Rhode Island state line.

Corps work in New London Harbor began in 1880, and in 1938, several modifications were completed. These include:

• A 3.8-mile-long main ship channel, 40 feet deep, and 600 feet wide, stretching from Long Island Sound to the State Pier at the northern end of the harbor, close to the US Route 95 Bridge. The deepening of the channel to 40 feet from its previous depth of 33 feet was completed in 1976 by the Department of the Navy. The Corps is responsible for maintaining the channel 40 feet deep and 500 feet wide, if required for military and commercial vessel traffic.
• A waterfront channel 6,000 feet long, 23 feet deep, and a minimum of 400 feet wide. This channel stems from the main channel and provides access to the city’s waterfront, including the Fort Trumbull, Shaw Cove, and the main pier areas. It splits into two branch channels at the State Pier.
• Two branch channels, each 23 feet deep. The east channel, between the State Pier and the Central Vermont Railroad Pier, is 100 feet wide and 1,000 feet long. The west channel, between the Central Vermont Railroad Pier and the New London shoreline (Winthrop Cove), is 250 feet wide and 1,500 feet long.
• A maneuvering area 23 feet deep located west of the waterfront channel and south of State Pier.
• An anchorage basin 15 feet deep in Shaws Cove.