1-1 Overview of the Kumamoto Earthquake and Damage
(1) Overview of the Kumamoto Earthquake
At 21:26 on April 14, 2016, a magnitude 6.5 earthquake struck the Kumamoto region of Kumamoto Prefecture, with a seismic intensity of 7 observed in Mashiki Town, Kumamoto Prefecture. This was followed by a magnitude 7.3 earthquake at 01:25 on April 16, with a seismic intensity of 7 observed in Mashiki Town and Nishihara Village (Fig. 1-1-1). These two violent tremors occurred within a short time of each other and triggered intense seismic activity from the Kumamoto district to the Aso district, along with central Oita Prefecture. As a result, there was immense damage in both Kumamoto and Oita prefectures, primarily in Mashiki Town and Nishihara Village.
This marked the first time that two tremors with a seismic intensity of 7 had been observed in the same region since the seismic intensity rating of 7 was added to the Japan Meteorological Agency’s seismic intensity scale in 1949, and the seventh time (including both of the Kumamoto quakes) that an earthquake with a seismic intensity of 6-lower or more has occurred. At least 4,000 earthquakes with a seismic intensity of 1 or more occurred over the six months or so from the first earthquake on April 14 (Fig. 1-1-2).
Fig. 1-1-1 Seismic Intensity Distribution
Earthquake at 21:26 on April 14 Earthquake at 01:25 on April 16
This seismic intensity includes the tremor from the M5.7 (reference value) earthquake that occurred in central Oita Prefecture immediately after this quake.
Source: Japan Meteorological Agency
(2) Damage
The Kumamoto Earthquake caused immense damage. Collapsing houses, landslides resulted in 228 fatalities, while a further 2,753 people sustained severe or minor injuries (Fig. 1-1-3). In addition, approximately 200,000 houses were completely, half and partially destroyed (Fig. 1-1-4).
The number of evacuation centers operated peaked at 855, while the number of evacuees reached approximately 184,000 at its highest (Fig. 1-1-5).
Fig. 1-1-3 Human Casualties
Fatalities: 228 People with severe/minor
injuries: 2,753 (i) Fatalities confirmed by means of police autopsy: 50
(ii) Fatalities due to exacerbation of injuries caused by the disaster or the physical burden of living as an evacuee: 170
(Of which, fatalities recognized by municipalities as having been caused by the disaster, pursuant to the Act on Provision of Disaster Condolence Grant:
167)
(iii) Fatalities caused by the torrential rain between June 19 and 25 that were recognized as being related to the Kumamoto Earthquake: 5
(iv) Fatalities recognized as having been caused by the disaster, pursuant to the Act on Provision of Disaster Condolence Grant: 3
((i)-(iii): Kumamoto Prefecture; (iv): Oita Prefecture)
Severe
*Figures for other prefectures represent the total across Fukuoka, Saga, Oita, and Miyazaki prefectures
Source: Data from the Fire and Disaster Management Agency (as of April 13, 2017)
Fig. 1-1-4 Extent of Damage to Houses
Prefecture
Houses damaged (buildings) Non-residential buildings
damaged (buildings) Fires
Source: Data from the Fire and Disaster Management Agency (as of April 13, 2017)
Fig. 1-1-2 Number of Earthquakes with a Seismic Intensity of 1 or More Observed by Date
Number 2016 Kumamoto Earthquake
(From 14:21 on April 14, 2016; total number with a seismic intensity of 1 or more each day)
Source: Japan Meteorological Agency
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Fig. 1-1-5 Changes in the Number of Evacuees and Evacuation Centers in Kumamoto Prefecture Due to the Kumamoto Earthquake
Source: Produced by the Cabinet Office from various materials, including the Report on the Review of Responses to the Kumamoto Earthquake Over a Period of Approximately Three Months (March 2017, Kumamoto Prefecture)
In addition, lifeline utilities such as electricity, gas, and water supply were damaged, with approximately 480,000 houses suffering power cuts at the worst point. Airports, roads, railways, and other transport infrastructure also suffered a huge amount of damage, causing significant disruption to the daily lives of local citizens and the business activities of small and medium-sized enterprises and operators in the agriculture, forestry, and fishery industries and the tourism sector.
Fig. 1-1-6 Extent of Damage to Lifelines
Maximum Number of Homes Affected Status of Restoration Electric
power
477,000 homes
(14:00, April 16, 2016) Restored April 20, 2016 Ministry of Economy, Trade and Industry data Gas 105,000 homes
(09:00, April 16, 2016) Restored April 30, 2016 Ministry of Economy, Trade and Industry data Water
supply
445,857 homes
(Cumulative total for the number of homes whose water was cut off at the worst point in each local government)
Restored July 28, 2016 Ministry of Health, Labour and Welfare data consolidated due to May 9 reopening of schools used
Slope failure in the area where the Aso-ohashi Bridge stood
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1-2 Response by the National Government
(1) Major Disaster Management Headquarters, etc.
After the Kumamoto Earthquake, the government established a Major Disaster Management Headquarters headed by then Minister of State for Disaster Management Taro Kono at 22:10 on April 14, 2016 (44 minutes after the earthquake struck), pursuant to the provisions of the Basic Act on Disaster Management. This headquarters put together a policy to serve as the basis for the swift and appropriate implementation of emergency measures for disaster. It then carried out tasks including the overall coordination of emergency measures in a diverse array of areas, such as rescue, first aid, and medical care, as well as gathering and distributing information, and liaising with Kumamoto Prefecture and affected municipalities.
In addition, to ensure that the government worked as an integrated team in the area of support for the daily lives of affected people, the Team to Support the Daily Lives of Disaster Victims was established on April 17.
Composed of vice-ministerial level officials from each ministry and agency, the team shared information and identified problems by reporting on the day-to-day status of each ministry and agency’s deliberations concerning issues and the results of their actions in response.
(2) On-site Major Disaster Management Headquarters
Following the magnitude 6.5 earthquake that struck the Kumamoto region, the government immediately deployed a Cabinet Office advance information-gathering team to Kumamoto Prefectural Office at 23:25 on April 14, 2016. At 10:40 the following day, an On-site Major Disaster Management Headquarters (hereinafter
“on-site disaster management headquarters”) headed by State Minister of the Cabinet Office Fumiaki Matsumoto was established at Kumamoto Prefectural Office. Each day, the on-site disaster management headquarters held joint meetings with the Disaster Response Headquarters headed by the Governor of Kumamoto Prefecture, which Kumamoto Prefecture had set up on April 14. The two bodies thus sought to ensure close collaboration. Kumamoto Prefecture disbanded its Disaster Response Headquarters on August 30, due to the fact that the search for missing persons had ended and the number of evacuees had declined. In light of this, the national government disbanded its on-site disaster management headquarters on September 16.
First meeting of the Major Disaster Management Headquarters
(Attended by Prime Minister Abe)
The on-site disaster management headquarters in action