Abstract
In this study, the flow and the topography change around the river-mouth bar are clarified by the measurement using ADCP. At the offshore side of river-mouth bar, the clockwise circulation is significant and the river-mouth bar advances toward the offshore. The growth rate of river-mouth bar is controlled by the sandy shoal which is formed at the terrace. After stopping the extraction of sediment at the offshore side of the river-mouth bar, the secular change of the sediment volume is approximately constant. Judging from this result, it is supposed that the sediment budget around the rivermouth bar is related to the extraction of sediment.
