Abstract
Recently, the vegetation and sand bar have been preserved from the viewpoint of maintaining the nature of river. On the other hand, preserved natural environment in the rivers may disturb the flood flow. In the past, most of the vegetation and sand bar had been removed in order to prevent the damage of floods such as the overflow of the bank. Therefore, the control of vegetation and sand bar becomes an important river engineering problem. The purpose of this study is to propose an accurate numerical model which can examine the effect of vegetation and sand bar in the Asahi River. The numerical results compared to high water marks of the flood of typhoon No.10 in 1998 show the usefulness of the presented numerical model.
