札内川における旧流路復元箇所における分岐部の流れの特性

抄録

In Satsunai River, maintenance of old channels is performed by artificial floods so that a river channel disturbance may arise at the time of a large-scale flood. The field survey and the numeric simulation were conducted to examine the characteristic of the flow at the bifurcation part considered to be important for maintenance of old channels. It became clear that there was a tendency for the rate of the flow which flows into the old channel to become high relatively at a small discharge. Moreover, it was found that the flow which flows into the old channel at the time of a large-scale flood is greatly dependent on upstream river channel form.