1 Japan and earthquakes
Before the Tohoku Earthquake
1.1 Japan and earthquakes
Japan has experienced countless powerful earthquakes. Before examination of the legal system on earthquake disaster preparation, this chapter briefly outlines the history of powerful earthquakes in Japan and the basic structures of government.
1.1.1 Powerful earthquakes in Japan
Japan is subject to all manner of natural disasters. In addition to powerful hurricanes battering the country every autumn, strong, recurring earthquakes have been known to strike periodically. The island nation is surrounded by four tectonic plates; the North American, the Pacific, the Philippine Sea, and the Eurasian plates.1 Pressure from these four plates and the subduction occurring when they butt up against one another causes forceful tremors. Historic records compiled over the past 2,000 years reveal a steady trend of recurring and extremely powerful earthquakes throughout the Japanese archipelago.2
The Kanto Earthquake (Kanto daishinsai) of 1 September 1923 was especially destructive.3 This earthquake struck the capital, Tokyo, shortly before noon at a magnitude of 7.9 on the Richter scale. It destroyed countless houses and buildings, including many government and office buildings, crushing untold numbers of people beneath rubble. Moreover, as many families had been cooking lunch at the time, widespread fires broke out causing fierce firestorms across the city. All told, some 1.9 million people were rendered homeless while more than 100,000 lost their lives or were classified as missing in one of the deadliest earthquakes in the nationâs history.4
However, the Kanto Earthquake is only one of many devastating earthquakes to have ravaged Japan. In 1854, the Tokai (Eastern Sea) Earthquake (Tokai jishin) (formally known as the Ansei Tokai Earthquake) struck central Japan, at a magnitude of 8.4 on the Richter scale, killing some 2,000 to 3,000.5 The epicenter was believed to be off the coast of Shizuoka Prefecture, just southeast of Tokyo. It is a well-known fact that strong earthquakes assail this area every 100 to 150 years. Merely one day later, an immensely powerful quake, known as the Ansei Nankai (Southern Sea) Earthquake hit yet another area in central Japan at an estimated Richter scale magnitude of 8.5, with more than 3,000 people losing their lives in the ensuing tsunami.6
Almost one hundred years later, on 7 December 1944, another destructive temblor bombarded central Japan. This earthquake came to be known as the Tohnankai (Southeastern Sea) Earthquake.7 The epicenter was off the coast of Mie Prefecture and the magnitude was estimated at 7.9 on the Richter scale. More than 1,000 people were killed or classified as missing. On 21 December 1946, yet another massive earthquake (the Shouwa Nankai Earthquake) struck off the coast of Wakayama Prefecture, registering at 8.3 on the Richter scale.8 Subsequently, a massive tsunami inundated several coastal cities in Kochi, Wakayama, and Tokushima Prefectures leaving more than 1,400 people dead or missing. These areas are also famously prone to violent earthquakes every 100 to 150 years.
Another massive earthquake is expected to hit Tokyo and the Kanto Region in the near future (another Kanto Earthquake). Still, there is broad consensus that the likelihood of a powerful earthquake assailing the Tokai area in central Japan is even more likely. Some sources put the likelihood of another Tokai Earthquake striking again within 30 years at more than 87%.9 Others predict that another Tokai Earthquake will hit together with another Nankai earthquake and Tohnankai earthquake, a triple mega earthquake also known as the Nankai Trough Megathrust Earthquake, and will inflict even more extensive damage.10
1.1.2 Preparing for earthquakes
Owing to Japanâs susceptibility to powerful earthquakes, the Japanese government has an imperative responsibility to prepare for these disasters. Thus, in 1961, the Diet (Japanâs national legislature), enacted the Basic Act on Disaster Countermeasures (saigai taisaku kihonhĹ).11 This Act was concerned with enabling a governmental response to natural disasters, including earthquakes. The Diet also enacted the Special Measures Act on Large-Scale Earthquake Countermeasures (daikibo jishin taisaku tokusohĹ) in 1978.12 This statute was premised upon the assumption that with close monitoring of the movement of faults and land, it is possible to predict powerful earthquakes, enabling a âwarningâ in advance of an earthquake, and prompting the central government as well as local governments to prepare countermeasures.
The primary responsibility to prepare and respond to natural disaster lies with the municipal government whereas the prefecture has a responsibility to assist the municipal government and the central government in primary disaster prevention planning and overall coordination of various countermeasures.13 With respect to emergency rescue operations resulting from natural disaster, it is primarily considered the job of rescue teams inside the fire department of the municipal government14 and the rescue team inside the mobile police force of the prefectural police force.15 These groups can provide assistance to those injured or trapped inside collapsed houses. It is the job of the fire department of the municipal government to extinguish any fires caused.16 If the disaster is more serious, Japanâs Self-Defense Forces (jieitai) (SDF) officers could be dispatched as an emergency rescue mission.17 With respect to normal natural disasters, including minor earthquakes, this is the system that is supposed to be employed.
The Basic Act on Disaster Countermeas...