2022 Volume 78 Issue 2 Pages I_235-I_240
In Chiba Prefecture, the yatsu topography is widely distributed, and using this topography is expected as one of the flood control measures. In this study, to construct a basin water routing model to evaluate the effect of flood mitigation in the Ichinomiya River basin, we did runoff analysis using hydrological topographic data with different grid resolutions and compared the calculation result of them. As a result, the peak discharge at 150m resolution was 64% of that at 30m resolution, and the calculated results were significantly different. It was shown that when the grid resolution is coarse, the local elevation difference peculiar to the yatsu is smoothed, underestimating the discharge flux, and as a result, underestimating the runoff to the river channel. The above showed that it is necessary to reflect topographical data with high resolution in numerical modeling in watersheds with yatsu topography.
PROCEEDINGS OF HYDRAULIC ENGINEERING
