In Japan, debris disasters often took place caused by intense rainfall that intensity is more than 70～80 mm/hr. Other characteristics of these intense rainfalls are as follows; 1) affected areas was small within limited areas, and 2) continued period was very short such as 1～5 hours. From 2010 to 2015 years, many debris flows took place by these intense rainfalls and many lives were killed by these debris flows. In order to save human lives from these debris disasters, evacuation is very important in addition to construct check dams. Such evacuation may be achieved by the risk information about for hazardous site and time. For the purpose to mitigate debris disasters, three wears, hard (to construct disaster prevention structures), soft (to delineate hazard area and to push risk information) and human (to participate in evacuation training and to evacuate), are pointed as important measures.
