日野川河道における土砂管理方策の効果

抄録

The sediment management for the purpose of restoration of sandy shore is implemented at the Hino River basin from mountain area to coastal area. We entrenched a part of a bar in the Hino river with the aim of run-off of deposited sediment on the bar into the sea. The trench is located where the main stream from upstream run upon the trench during times of flooding. The bed elevation of the trench was determined so as the bed material of the trench moves under the condition of the averaged annual maximum discharge by using 2D flood flow numerical simulation and so as to be similar to the bed elevation of bare area around the bar. The largest flood in recorded history was occurred in September 2011. A large part of the bar was flushed by the flood and produced the effect as expected.