NUMERICAL SIMULATION OF FLOOD LAKE BEHAVIOR IN NORTHEASTERN BANGLADESH

摘要

In Sylhet, a low-lying region located in northeastern Bangladesh, a large number of depressions store rain and floodwater during the rainy season. These flooded areas become large lakes. Such a flood lakes is referred to as a Haor. The largest flood lake (Haor) in Bangladesh is Hakaluki Haor, which extends over as much as 700 km~2. Local People use Hakaluki Haor as grassland, for farms and for conditional paddy fields that fill during the dry season. During the rainy season, Hakaluki Haor acts as a water reservoir and allows transportation via boat or bamboo raft. In the present paper, in order to clarify the hydrological and hydraulic behavior of Hakaluki Haor during the rainy season a numerical inundation model was developed, in which one-dimensional and two-dimensional unsteady flow equations are applied to rivers and the flood plain, respectively. In addition, the behavior of Hakaluki Haor and the possibility of developing this area after simulating the flooding process of 1988 are discussed.