2016 Volume 69 Issue 4 Pages 37-43
Debris runoff occurred due to heavy rainfall of Typhoon MALOU in Kakidairasawa, Numata City, Gunma Prefecture on Sept. 7, 2016 and caused damage on 4 houses. After the disaster, research team was immediately organized by the Kanto Branch, Japan Society of Erosion Control Engineering with the aim of investigating the processes of generation, flow and deposition of debris movement and clarifying the actual conditions of debris disaster. Following features are observed : 1) the debris runoff was caused by the short period torrential rainfall, 2) the debris runoff was affected by large amount of surface runoff, 3) pumice layers were exposed by the erosion of stream bed, 4) a woody debris dam was formed by deposit of logs and sediment in the stream.
