Cases of Damage Caused by Mountain Hazards that Occurred in Japan from 2014 to 2022

In Japan, significant heavy rainfall events in Hiroshima in 2014 and 2018, in northern Kyushu in 2017, and Typhoon Hagibis (Typhoon No. 19) in 2019 caused extensive water and soil runoff in various mountainous watersheds. These events were associated with the occurrence of a large number of collapsed soil masses of various sizes. In order to clarify the geological overview and damage status of six mountain disasters that occurred in Japan from 2014 to 2022, we have organized the data from disaster report materials and aerial photographs, LiDAR DEMs. Target areas are Tamba City, Hyogo Prefecture (August 2014), Asakita Ward, Hiroshima Prefecture (August 2014), Asakura City, Fukuoka Prefecture (July 2017), Kure City, Hiroshima Prefecture (July 2018), Marumori Town, Miyagi Prefecture (October 2019), and Murakami City, Niigata Prefecture (August 2022). Heavy rains occurred in the Tamba area due to the effects of a stationary front from August 14 to 17, 2014, and in Tamba City, the total volume of soil washed away due to slope failures and debris flows was estimated to be approximately 500,000 m3, which caused landslides. Damage was confirmed at a total of 256 locations, 104 of which were near people’s homes. The damage caused 1 death and 4 injuries, 18 homes were completely destroyed, 51 homes were partially destroyed (9 were extensively damaged and partially destroyed), and 954 homes were partially damaged. In the Asakita area, heavy rains caused by a stationary low-pressure front from August 15 to 17, 2014 caused landslides at 167 locations, resulting in 76 deaths, 68 injuries, and 179 homes completely destroyed. The damage was severe, with 217 houses partially destroyed and 190 partially damaged. A total of 182 landslide disasters caused by debris flows, landslides, and landslides were reported in the Kure area, with 20 people injured and 227 homes damaged.