The Asan River Flood Control Project is about midway along the western coast of Guam, approximately two miles west of Agana. The project was authorized under Section 205 of the Flood Control Act of 1948. It was completed and dedicated in June 1985 at a cost of $1,901,134 (Federal: $1,275,500; non-Federal: $625,634).
The project consists of a 592-foot-long grass-lined channel along the Calacag River above its confluence with Asan River; realignment of portions of Asan River; a riprap channel along Asan River extending 1,054 feet upstream of Marine Drive; and modification of the Marine Drive culvert. The channel downstream of Marine Drive remains unlined.
The overall project includes a drainage swale totaling 1,960 feet, east of Asan River to divert storm runoff toward the ocean. The local sponsor is the Government of Guam, Department of Public Works (DPW). To date, the project has prevented more than $3.18 million in damages.