Tsunami Preparedness: Is Zero Casualties Possible?

Eddie N. Bernard

doi:10.1007/s00024-022-02948-7

Abstract

Inspired by the goal of Kuroshio Town, a coastal community in southern Japan, to have zero casualties from the next tsunami, this study will focus on a tsunami preparedness program to save everyone’s life. The first step in the program is to determine how many people in a tsunami hazard zone can be protected using existing horizontal and vertical evacuation procedures and shelters. The people who live or work in tsunami hazard zones but cannot or will not use these shelters are identified as “unprotected”. A possible solution to save the “unprotected” is to offer a shelter-in-place option to complement the horizontal and vertical evacuation options. Such a shelter-in-place option would provide protection for those unable or unwilling to use horizontal or vertical evacuation facilities. The shelter-in-place option would offer customized protection for individuals and businesses free of contagious diseases found in gatherings associated with horizontal or vertical evacuation shelters. To be effective, the shelter-in-place option must be immediately accessible to protect people from drowning, being crushed, being hit by floating objects, suffocation by ingesting silt laden water, fires, and hypothermia. An example of a shelter-in-place product is a patented, spherical aluminum capsule that floats on the tsunami protecting people from fire, cold water, being crushed, ingesting contaminated water, being hit by floating objects, and drowning. Since the capsule floats, there is no need to accurately predict tsunami flooding heights. This study includes numerical model simulations for 20 capsules subjected to 3 tsunami flooding scenarios in Newport, Oregon indicating the capsules have a low probability of being washed out to sea. Using a shelter-in-place option, along with horizontal and vertical evacuation options, zero casualties from the next tsunami is possible.

Highlights

Inspired by the goal of Kuroshio Town, a coastal community in southern Japan, to have zero casualties from the tsunami, this study will focus on a tsunami preparedness program to save everyone’s life
A possible third option for those who are unable or unwilling to evacuate is a shelter-in-place option where an appropriate shelter is immediately available to people who live or work in a tsunami hazard area
The 4-person and 12-person capsule options are 34–53% less expensive than the vertical evacuation option on a cost/person comparison

Summary

Horizontal and Vertical Evacuation Case Studies

The town of Kuroshio Town Japan is aiming to have zero victims from the tsunami. Unwillingness to evacuate is a real problem that can lead to more tsunami deaths Their second option is vertical evacuation (Fig. 5) where about 300–500 evacuees climb a 3–5 story tsunami structure to escape tsunami flooding and death. There is the issue of people unwilling to evacuate because they don’t want to gather in the structure due to fear of building failure (McCaughey et al, 2017), personal safety, disease, overcapacity or Figure 5 Problems with vertical evacuations. After the horizonal evacuation upgrades and vertical structures were installed, they conducted additional drills to determine the numbers of unprotected people An unwillingness to evacuate indicates that more options are needed to have zero casualties from the tsunami

Shelter-in-Place Option

Simulations of Capsule Trajectories During Tsunami Flooding

Findings

Conclusions