Agat Small Boat Harbor is located on the west coast of Guam near Gaan Point. The project was authorized for construction in June 1986 under Section 107 of the River and Harbor Act of 1960, as amended. It was completed in March 1989 at a total cost of $2,821,800 (USACE: $1,711,500; Coast Guard: $2,000; non-Federal: $1,108,300).

The project consists of an entrance channel (930 feet long, 120 feet wide, 14 feet deep); a turning basin (120 feet long, 150 feet wide, 7 to 11 feet deep); a main access channel (500 feet long, 75 feet wide, 9 feet deep); two breakwaters (985 feet long and 50 feet long); and two revetted moles (180 feet long and 300 feet long). The protected basin provides berthing areas for up to 150 boats. The local sponsor is the Government of Guam.