Facing Japan’s Extreme Weather Challenges

Addressing Natural Disaster Risks: The Need for Greater Self-Reliance

Society

When the city of Kamaishi, Iwate Prefecture, was hit by a tremendous tsunami following the Great East Japan Earthquake in 2011, almost all of its 3,000 elementary and junior high school pupils survived. They were quick to flee thanks in part to the disaster-preparedness training by Katada Toshitaka, who here calls for greater self-reliance in the face of the growing risks from natural disasters.

The Critical Danger of Widespread Flooding in Tokyo

I am now also involved in the disaster-prevention efforts of the Tokyo metropolis, particularly with regard to the so-called zero-meter zone, where the land is at or below sea level. All that separates this zone from the adjoining waters is a series of narrow levees. And it is home to a huge number of people. Earthquakes are of course the biggest danger for the capital, but as typhoons grow more intense, the danger of storm surges has also become an urgent issue.

When a typhoon approaching the Tokyo area from the south is preceded by wet air that causes heavy rains to fall in the prefectures north of the capital, particularly Gunma and Saitama, the rising waters of two major rivers, the Tonegawa and Arakawa, all end up pouring into Tokyo. There is a danger that this could lead to a worst-case scenario: strong winds making it hard for people to flee, rising river water, and a storm surge from the bay. Edogawa Ward, 70% of which lies within the zero-meter zone, would likely be hard hit. It has a population slightly under 700,000, and if these people were to evacuate, they would need to do so across a wide area. According to a simulation we did, there would be bottlenecks on the bridges over which residents would need to flee. These bridges are affected by traffic congestion during the everyday morning rush hour, and if an evacuation advisory were issued and residents rushed to the bridges en masse, movement could quickly grind to a halt. Unable to move and caught in rising winds, the fleeing residents could then be hit from water surging through breaks in the levees. This is truly a terrifying scenario.

So the biggest problem in Tokyo’s case is how to cope with the huge flow of people attempting to evacuate. In order to avoid dangerous congestion, the flow needs to be dispersed either geographically or temporally. Geographical dispersion means assigning evacuation destinations across a wide area. But the neighboring wards of Katsushika, Adachi, Kōtō, and Sumida all have their own zero-meter zone problems. Under the Disaster Countermeasures Basic Act, dealing with large-scale flood disasters is under the purview of municipal mayors. So steps like the issuance of evacuation advisories are implemented at the municipal (city, ward, town, or village) level. And there is no mechanism for coordination in the case of a wide-area evacuation involving multiple municipalities.

The first question is who will judge the severity of the situation. If a wide-area evacuation call is issued as a typhoon approaches and a large number of residents respond by fleeing, but it then does not actually strike the area in question, the social repercussions may be huge. On the other hand, hesitation to issue an evacuation call in a timely manner could in the worst case result in tremendous loss of life.

A weighty decision like this cannot be left up to local municipalities like Edogawa. And the Tokyo metropolitan government has no intention of taking responsibility either. The same applies to the other great metropolises of Osaka and Nagoya. When an approaching disaster necessitates evacuation of a wide area, how is the situation to be assessed and who is going to manage the traffic? These are urgent issues, and I am extremely alarmed at the almost complete lack of progress in addressing them.

Developing an Awareness of Natural Disasters as a Common Enemy

In the case of the United States, the decision-making system for large-scale disasters is clearly defined on the national level. The president declares a state of emergency and gives the administrator of the Federal Emergency Management Agency full power to deal with the situation.

Japan should move urgently to create its own system for the national or prefectural authorities to take charge when there is a danger of a large-scale disaster that cannot be handled at the municipal level. At the same time, local residents need to wean themselves from dependence on the government and act on the understanding that they are responsible for protecting their own lives. In a big city like Tokyo, it is difficult to expect community residents to take the initiative in implementing disaster preparedness and mitigation activities. But I think we should try to get residents of areas with shared disaster-vulnerability features to recognize disasters as a common enemy that they need to confront together. This, I believe, can serve as a way of building community spirit.

Japanese people must develop a mind-set of self-reliance and mutual aid in coping with disasters, recognizing the limits to what the government can do for them. Only in this way can we achieve major progress toward the goal of preventing disaster-related fatalities.

 (Original Japanese article based on an August 18, 2014, interview. Banner photo: The Yagi district of Hiroshima’s Asaminami Ward, where landslides caused by torrential rains resulted in many deaths on August 20, 2014. © Jiji Press.)

▼Further reading
“Guerrilla Rainstorms” Assault Tokyo
Sudden, localized summer downpours, known as “guerrilla rainstorms,” have become a recurring problem in Japan. They are particularly prevalent in Tokyo and other large cities, where the “heat island” phenomenon is believed to contribute to their regular occurrence.
In the Path of the Storm: Japan and Typhoons
Typhoons are a part of life in Japan, with several storms lashing the archipelago every year. So far in 2014 typhoons have blustered Okinawa, flooded rivers in Kyoto, and triggered flooding and landslides on the island of Shikoku.

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Great East Japan Earthquake tsunami disaster global warming Kamaishi weather typhoon extreme weather Haiyan Hurricane Katrina FEMA

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