Bili]bili Dam located in Sulawesi Selatan, Indonesia was built as a multipurpose dam. However, it has lost its sediment capacity by deposit resulted from the collapse of Mt. Bawakaraeng. Since then, there has been a criticism that the construction of Bili]bili Dam was not appropriate at the very place. Without Bili]bili Dam, sediment in the river by the collapse would have possibly triggered serious sediment disasters in downstream areas. We evaluate effectiveness of Bili]bili Dam as a sabo dam which prevents sediment from flowing downstream. We simulate one]dimensional riverbed variation of the Jeneberang River and two]dimensional flood in the downstream areas of Bili]bili Dam. The results of one]dimensional riverbed variation simulation show that 22million m3 of sediment would flow downstream in twenty years and the riverbed would rise up to 10m. The results of two]dimensional flood simulation show that the floodwater would inundate 68km2 of the areas including highly populated residential areas. Therefore, Bili]bili Dam functions effectively as a sabo dam.

Key wordsFBili]bili Dam, sediment transport, riverbed variation, flood simulation