5.2.2 Key factors for combined and large-scale disaster management

From the international study, it can be inferred that the world has experienced several large and combined disasters compared to previous decades. Preparing for such disasters is one of the actual urgent needs in terms of disaster management.

Based on the study’s findings, the properties of large-scale and combined disasters can be defined using the following characteristics:

• Unfamiliarity of the event
• Affected area or intensity of large-scale disaster.
• Single or multiple disaster mode
• Frequency
• Potential consequences

For managing those disasters in the road network, preparedness should be up to date and new concepts are needed. These concepts should take into account the important key words identified in major Safety Burst situations: robustness, self-sustainment and dynamic risk management (see Figure 5.2.2).

Based on the findings of the international survey, no differences could be found in preparedness for large and combined hazards from that assumed for common-scale disasters. However, a new concept for disaster management considering the Safety Burst condition is emerging after the 2011 combined and serious nuclear plant disaster that occurred in Japan. The road system and network should be well prepared against safety burst situations in which damages are propagating in space and expanding in time often resulting that the expected performance of the system becomes out of control. The recommendations considering such conditions are proposed as follows:

• Robustness: The road system and road network should be redundant and resilient and thus, relative insensitive to minor disturbances against both foreseen and unforeseen events. Shut down of the important lifeline will result in the difficulty for rescue and restoring activities. The road administrators should consider new concept the “disaster resilience” in road plan, design and operation.
• Self-sustainment: The road system and road network should be well operated in order to keep the road function in disasters. Adequate preparedness which would account for early warning, evacuation routing, and routing restoration should guide the operating rule of the road against foreseen and unforeseen events. Public education and training are also very important because the success of the operation in disasters depends on the public awareness and respect for the rule.
• Dynamic risk management: The road system and road network should be monitored, controlled and managed by road administrators in communication, coordination and cooperation with other organizations because of the limited availability of resources of the road administrators. ITS will be one of the powerful tools for dynamic management for improving the capacity of the road administration and its capability for adjusting and adapting to the circumstances of continuously changing conditions.