4:15 PM - 4:30 PM
[HDS08-09] A Study on Human Damage Potential in Heavy Rain Disaster
Keywords:Heavy Rain Disaster, Evacuation
In recent years, climate change has led to a greater frequency of rainfall events that exceed river maintenance standards. In 2015, the Flood Control Act was revised to change the rainfall assumption for flooding area mapping from planned rainfall (once every 50-200 years) to expected maximum rainfall (approximately once every 1,000 years), which is also explicitly prohibited in evacuation. In 2015, the Flood Prevention Law was revised to change the rainfall assumption for flood zone mapping from planned rainfall (once in 50-200 years) to maximum rainfall (approximately once in 1,000 years), and to explicitly consider the hazard of excess external forces in evacuation.
Yamori et al. classified cases of torrential rain disasters into four types based on two axes: whether or not the disaster phenomenon was manifested and whether or not human casualties were caused. The objective of this study is to identify potential cases before the occurrence of disaster phenomena.
In this study, human suffering is considered to be highly likely to be caused by a lack of a sense of urgency about disasters, and human suffering potential is defined as an area with high human suffering potential, where flood damage is small in high frequency probability rainfall events, but is large in low frequency probability rainfall events with excess external forces. We attempted to visualize the distribution of such areas.
The data used were the 10-year, 100-year, and 200-year probability rainfall data from the Shiga Prefecture Disaster Prevention Information Map of maximum inundation depths. This data shows the area of inundation depth categories set according to each probability: 001 (less than 0.5 m), 002 (0.5~1.0 m), 003 (1.0~2.0 m), 004 (2.0~3.0 m), 005 (3.0~5.0 m), 006 (3.0~4.0 m) and 007 (5.0 m or more). The areas where the maximum inundation depth is 0 or 001 in the 10-year probability rainfall category and the maximum inundation depth is 2 m or more (004, 005, 006, 007) in the 200-year probability rainfall category, which is the excess external force, are created using GIS, and the areas where buildings are located are extracted from the lot number map information. The result was a distribution of human casualty potential in Shiga Prefecture, with 28 locations in the prefecture. As a result, 28 areas in Shiga Prefecture were identified as areas with high human casualty potential. The figure shows the human casualty potential distribution for the Torahime area of Nagahama City. The figure shows that the target areas are located not in the areas with high inundation depths, but in the surrounding areas in the flood zone map that assumes a 200-year probability of inundation. It can be considered that the district is affected by the fact that frequent rainfalls do not require evacuation.
In the future, we intend to conduct interviews with residents in the districts taken out in this study to verify the effectiveness of the proposed human damage potential.
Yamori et al. classified cases of torrential rain disasters into four types based on two axes: whether or not the disaster phenomenon was manifested and whether or not human casualties were caused. The objective of this study is to identify potential cases before the occurrence of disaster phenomena.
In this study, human suffering is considered to be highly likely to be caused by a lack of a sense of urgency about disasters, and human suffering potential is defined as an area with high human suffering potential, where flood damage is small in high frequency probability rainfall events, but is large in low frequency probability rainfall events with excess external forces. We attempted to visualize the distribution of such areas.
The data used were the 10-year, 100-year, and 200-year probability rainfall data from the Shiga Prefecture Disaster Prevention Information Map of maximum inundation depths. This data shows the area of inundation depth categories set according to each probability: 001 (less than 0.5 m), 002 (0.5~1.0 m), 003 (1.0~2.0 m), 004 (2.0~3.0 m), 005 (3.0~5.0 m), 006 (3.0~4.0 m) and 007 (5.0 m or more). The areas where the maximum inundation depth is 0 or 001 in the 10-year probability rainfall category and the maximum inundation depth is 2 m or more (004, 005, 006, 007) in the 200-year probability rainfall category, which is the excess external force, are created using GIS, and the areas where buildings are located are extracted from the lot number map information. The result was a distribution of human casualty potential in Shiga Prefecture, with 28 locations in the prefecture. As a result, 28 areas in Shiga Prefecture were identified as areas with high human casualty potential. The figure shows the human casualty potential distribution for the Torahime area of Nagahama City. The figure shows that the target areas are located not in the areas with high inundation depths, but in the surrounding areas in the flood zone map that assumes a 200-year probability of inundation. It can be considered that the district is affected by the fact that frequent rainfalls do not require evacuation.
In the future, we intend to conduct interviews with residents in the districts taken out in this study to verify the effectiveness of the proposed human damage potential.