Cross Rip Shoals are among the many shoals scattered throughout the central part of Nantucket Sound. Cross Rip Shoals are about 14 miles south of Hyannis Harbor and 15 miles northwest of Nantucket Harbor.

The Corps’ project consists of a 1.7-mile-long channel, running east to west, that is 30 feet deep and 4,000 feet wide. The width of the channel stretches between Halfmoon Shoal on the north and Cross Rip Shoals on the south. The channel is used principally by deep-draft vessels passing through Nantucket Sound.