Considerations on hazard prediction method with rainfall index in the case of 2014 Hiroshima landslide disaster

Abstract

On 20th August, 2014, a series of slope failures and debris flows occurred around city of Hiroshima, Japan. The debris flows took place at 107 valleys and slope failures occurred at almost 59 locations between 3 am to 4 am., costing 74 lives and left 44 injured. This calamity was caused by the 2 hours and more continuing torrential rainfall of more than 80 mm/h intensity, which took place under the squall line formed by a sudden weather change. In this report, the considerations were made on how the present hazard prediction methods with the rainfall index were applied and worked in this disaster. The points to be improved were discussed.