Debris-Wood Capture Effect Controled by Concrete-Slit Dam Under Low-Gradient Flow

In 2017, heavy rains upstream of sabo dams in northern Kyushu, Japan, caused several disasters downstream due to debris-wood flow. These disasters demonstrated the necessity of protective measures against debris-wood flow throughout the entire river basin area. Therefore, it is necessary to examine the potential effects of such measures on the function of concrete slit Sabo dams, which are installed in regions of low-gradient flow. Based on our experimental results, we propose a technique to capture debris-wood in the backwater of concrete slit Sabo dam pools. We further propose the in-stallation of wire-net countermeasures against debris-wood spill-out, and provide detailed diagrams illustrating the mechanisms of these countermeasures.