Southport Harbor is located at the mouth of the Mill River in Fairfield. The harbor is used primarily for recreational boating.
Corps work on Southport Harbor began in 1829 and has since undergone several modifications. The project currently consists of:
A 1.1-mile-long, nine-foot-deep channel extending from Long Island Sound to Golf Club Wharf. From Long Island Sound to East Main Street, the channel is 100 feet wide. From East Main Street to Golf Club Wharf, the channel varies in width between 175-400 feet.
A six-foot-deep anchorage area north of Golf Club Wharf, 300 feet wide and 500 feet long.
A 1,320-foot-long stone breakwater on the east side of the harbor entrance.
A 1,350-foot-long training dike along the east bank of the river.