Disaster Mitigation Policy in Japan

by

Koji Ikeuchi1 and Nobuharu Isago2

ABSTRACT responsibilities of national and local governments, the relevant stakeholders of the This paper presents the state-of-the-art of public and private sectors cooperate in earthquake disaster mitigation policy in Japan. implementing various disaster countermeasures. The status that Japan is prone to have damage The Central Disaster Management Council from earthquake is dictated. The outline of (CDMC) is established in the Cabinet Office large-scale earthquake such as Tokai, Tonankai based on the Disaster Countermeasures Basic and Nankai, Japan and Chishima Trench and Act. The council, whose chairperson is Prime Tokyo Metropolitan , the result of Minister, promotes comprehensive disaster estimated damage, and the countermeasures countermeasures including deliberating such as their general measures, disaster important issues on disaster reduction. In this reduction strategy and emergency response plan paper, the outline of earthquake disaster are also introduced. mitigation policy in Japan is introduced.

KEYWORDS: disaster mitigation, large-scale 2. EARTHQUAKES IN JAPAN earthquake, the Central Disaster Management Council, Tokyo Metropolitan Earthquakes Figure 1 shows the plate around Japan. Japan locates the peripheral part between oceanic plate 1. INTRODUCTION ( and ) and inland plate. Pacific Plate sinks under inland People’s lives and economical property were plate and Philippine Sea Plate at Chishima greatly lost up to now because numerous Trough, Japan Trough and Izu-Ogasawara large-scale earthquakes and tidal wave () Trough. Also Philippine Sea Plate sinks under happened under the plate and the topographical inland plate at south-western trough, Nankai condition. To protect national land as well as Trough, and . citizen’s lives, livelihoods, and property from This indicates that Japan, locating on the natural disasters including earthquake is an complex crust structure, has more earthquakes important national policy. comparing with other countries and have much damage from past earthquakes. The Along with a series of reforms of the central earthquakes over 6 minus of earthquake government system in 2001, the Cabinet Office intensity in Japanese scale happened 13 times was established to handle the general affairs (25 times when each aftershock was counted which Prime Minister should be in charge. The from the Hyogoken Nambu Earthquake in 1995 Cabinet Office performs planning, making and to the Noto Hanto Earthquake in 2007). executing of general and important policy. As for the area of disaster management, the There are two types of large-scale earthquakes Director-General for Disaster Management is which heavy damages were brought. One is mandated for the necessity of unifying the the type that occurs near the boundary of plate, policies among related government and this is divided into the type occurred organizations. Japan’s disaster management 1 Director for Earthquake and Volcanic Disaster system addressed all of the disaster phases of Management, Disaster Management Bureau, Cabinet prevention, mitigation and preparedness, Office, 1-2-2 Kasumigaseki, Chiyoda-ku, Tokyo 100-8969 emergency response as well as recovery and Japan rehabilitation. With clear roles and 2 Deputy director, ditto between the plates and the type occurred within disaster such as the delay of quick response to oceanic plate. The typical example of grasp the degree of disaster, that is, the number earthquake occurred between the plates was the of casualties and collapsed houses because of Kanto Earthquake in 1923 and the Nankai insufficient information gathering, severe Earthquake in 1946. This kind of earthquake difficulty of rescue activities for evacuation, life occurs when the deformation recovers after the saving and emergency transportation due to the deformation with plate’s sinking in reaches its destruction of transportation facilities and heavy limit. Its frequency is generally said every traffic congestion, material conveyance, medical several hundred years. The Tokai, the activity, voluntary activity, life reconstruction Tonankai and Nankai Earthquake occurred in for people requiring assistance during disaster near future are predicted as this type. such as elderly.

The other type is the one in inland shallow area Various policies have been executed on the basis that strain energy is accumulated by deformation of past experience. The CDMC has estimated of inland plate resulted from plate’s sinking in the damage of earthquake and some and the energy is released by the disruption of countermeasures are proposed for the large-scale underground fault. The typical example of this earthquakes in the next few decades, such as the kind of earthquake was the Hyogoken Nambu Tokai Earthquake, Tonankai and Nankai Earthquake in 1995, the Niigataken Chuetsu Earthquake, Earthquakes around the Japan and Earthquake in 2004, and the Noto Hanto Chishima Trenches, and Tokyo Metropolitan Earthquake in 2007. Earthquakes. Figure 2 shows the location of four large-scale earthquakes above mentioned. The outline of countermeasures and so on

North against these earthquakes is following below. American Plate

Eurasian Plate Chishima trough 1. Tokai J trough a Pacific Tokyo p Plate ima a n Chish t 2. Tonankai- r 3. Japan o Nankai Philippine u n h and a Sea Plate g g p h u a Chishima o

J r t trench

h 4. Tokyo ug ro Metropolitan ait nk Fig.1 Plates around Japan Na

Fig.2 Outline of large-scale earthquakes 3. COUNTERMEASURES AGAINST LARGE-SCALE EARTHQUAKES 3.1 Flow of planning countermeasures against The main cause of many casualties in the large-scale earthquakes Hyogoken Nambu Earthquake in 1995 was Figure 3 shows the planning flow of measures reported as building collapse and crushed body for earthquake in government. with it and more than 80% of casualties were Firstly, the area of epicenter and earthquake resulted from it. The fire around dense area of model is supposed, and the intensity and house also added the number of casualties． In distribution of earthquake tremor and so on are addition, some problems were reported from this estimated. Next, the damage of death person and collapsed buildings are estimated on the with a possibility of being predicted just before basis of earthquake tremor and so on. it occurs. Therefore, eight prefectures Following, general measures, in other words, including Shizuoka prefecture which will have master-plan for mitigating the damage are most damage in the Tokai Earthquake are regulated on the basis of the damage estimate designated as the areas for intensified measures results. Next, strategy by regulating under the act. quantitative damage reduction targets and the underpinning measures are decided. Finally, A death toll of approximately 9,200, total emergency response plan, that is, contingency number of collapse or burned houses of 260 operation plan for all of governments, including thousand and a maximum economic loss of 37 concrete function and the degree of backup are trillion JPY is estimated at the worst case when decided. it occurs.

On the result of damage estimation, the CDMC 1. Supposition of earthquake model and area of decided the ‘General Measures for Tokai epicenter and estimation of earthquake tremor etc. Earthquake,’ containing such main issues as 1) implementation of urgent upgrade of seismic 2. Damage estimates resistance measures, 2) reinforcement of community capabilities against disasters, 3. General Measures (Master Plan) 3) establishment of a tangible disaster management system in the case of a warning 4. Strategy declaration and 4) establishment of wide-area management system in occurrence of disaster. 5. Emergency Response Plan

Kyoto Fig.3 Flow of planning countermeasures Shikoku ： Source Region against large-scale earthquakes of Earthquakes

3.2 Countermeasures for Tokai Earthquake Suruga Trough Nankai Area Tonankai Area Figure 4 shows the time history and location 1605 1605 Keicho Earthquake (M7.9) relating to the Tokai, the Tonankai and Nankai 102 years Earthquake. After the Ansei-Tokai Earthquake 1707 1707 Hoei Earthquake (M8.4) in 1854, strain on the earth’s crust along Suruga 32 hours 147 years 1854 Ansei-Tokai Earthquake (M8.4) Trough has been building up ever since, 1854 1854 Ansei-Nankai Earthquake (M8.4) 90 years approximately 150 years. Therefore, it is 2 years 1944 Tonankai Earthquake (M7.9) 1944 153years 1946 believed that there is a high possibility of the blank Death / Missing 1,223 1946 Nankai Earthquake(M8.0) Tokai Earthquake occurring. 2007 ？ Tokai Death 1,330 Earthquake? Under the Act on Special Measures for Large-Scale Earthquake, the mitigation for Fig.4 Time history and location relating to disaster damage is aimed by designating the Tokai, Tonankai and Nankai Earthquake areas for intensified measures against the earthquake in advance, where the observation system has been reinforced and earthquake As for the ‘Tokai Earthquake Disaster Reduction response system in the case of a prediction Strategy,’ the goal to halve the estimated death report being announced has been developed for toll and economic loss in the next decade is set. the large-scale earthquake with a possibility of being predicted just before it occurs. The CDMC also formulated the ‘Guidelines for Tokai Earthquake Emergency Response The Tokai Earthquake is the only one at present Activities,” and the activities of each disaster management related organization were Under the act, promoted area to advance the determined to execute rapid and proper countermeasure for reduction of damage is emergency response activities in terms of each designated and the set-up of the plan including level, such as at the time of caution information, the evacuation measure from tsunami and the warning declaration and disaster occurrence. arrangement of the facilities including Furthermore, a detailed plan of action was observation site are regulated. decided to designate the content of concrete activities for emergency operations such as It is said that the maximum risk of death may be search and rescue, firefighting and medical approximately 18,000, of which about 8,600 activities, procurement of material, and may be attributable to . Total number transportation activities. In this detailed plan, of collapse or burned houses of 360 thousand two types of plan are made; one is predictive and a maximum economic loss of 57 trillion JPY type when the prepared activities would be is estimated at the worst case when it occurs. finished between the warning declaration and occurrence of earthquake, and the other is The general measures, the disaster reduction sudden type when no warning declaration is strategy and the guidelines for emergency made and the earthquake occurs suddenly. response activities are decided. Concrete plan for activities were shown in the Secretary Start of emergency response after grasping the Organization of the CDMC in March, 2007. damage situation will be late when big disaster happens. For the Tokai Earthquake, in advance, 3.4 Countermeasures for Trench-type that is, before disaster, the concrete and detailed Earthquakes in the Vicinity of the Japan and plan of activity including the contents and Chishima Trenches volume of dispatch and material are set on the There have been many large-scale earthquakes result of damage estimate to cope with that. of magnitude 7 or 8 scale with plate’s sinking Just after big disaster, preparing dispatch and occurring in the vicinity of the , procurement of material is started on the basis of extending in the oceanic areas from off of this plan, and emergency response about rescue eastern Chiba to Sanriku, and in the vicinity of and medical activity is executed. Activity the Chishima Trench, extending from the areas content will be amended after obtaining off Sanrinku, Tokachi and Etrofu Island. There information. are many damages of tsunami, such as the Meiji Sanriku Earthquake in 1896 with casualties of 3.3 Countermeasures for Tonankai and Nankai 22 thousand and the Syowa-Sanriku Earthquake Earthquake in 1933 with 3 thousands of death or missing The Tonankai and Nankai Earthquakes with a people. magnitude of 8 or so have occurred at intervals of 100 to 150 years as well as the Tokai There are many type of earthquakes occurred in Earthquake. Most recently, it occurred in 1944 the vicinity of plates or inside the plate. Also, and 1946 respectively, and it is anticipated that so-called ‘tsunami earthquake’ which did not the next ones will occur in the first half of this have so heavy tremor but bring much damage by century. tsunami happened. The Miyagiken-oki Earthquake is said to occur at intervals of Large damage over the wide area is predicted approximately 40 years and imminence of heavy tremor and big tsunami in the Tonankai earthquake occurrence is pointed out in this and Nankai Earthquake. ‘Act on Special area. Measures for Promotion of Tonankai and Nankai Earthquake Disaster Management’ was It is said that the maximum risk of death may be regulated to advance the countermeasure for approximately 2,700 in the type of the Meiji disaster management steadily. Sanriku Earthquake, total number of collapse or burned houses of 21 thousand and a maximum economic loss of 1.3 trillion JPY is estimated in set through upgrade of seismic resistance of the type of the Miyagiken-oki Earthquake. The houses and buildings, fix of household furniture, general measures for this earthquake focusing improvement of densely populated urban area, on issues such as the promotion of tsunami nourishment of voluntary disaster management disaster countermeasures, the construction of organization, reinforcement of transportation towns capable of withstanding tremors and facilities and promotion of tackling business addressing problems unique to snowy and cold continuity. areas, is decided. In addition, the guidelines for emergency response activities are decided.

3.5 Countermeasures for Tokyo Metropolitan Earthquakes In the capital area around Tokyo, the Kanto Shinjuku-ku Earthquake occurred in 1923 and brought heavy damage. The earthquake with magnitude 8 or Chiyoda-ku so like the Kanto Earthquake occurs every 200 Arakawa river or 300 years in the boundary of plate around the Chuo-ku Sagami Trough, extending from the Sagami Bay Minato-ku in southeast direction. The next earthquake with same level will be expected to occur after 100 or 200 years, however, some earthquakes with magnitude 7 or so may happen in southern Fig.5 Distribution of collapsed buildings due to Kanto area during this period. seismic activity in Tokyo Metropolitan Earthquakes

Figure 5 shows the distribution of collapsed buildings due to seismic activity in Tokyo 【 Disaster Reduction Objective】 Metropolitan Earthquakes. In the worst case, Halve the number of casualties within next 10 years ・Wind 15m/s Approx. 11,000 → 5,600 people 11 thousand of casualties, total number of ・Wind 3m/s Approx. 7,300→ 4,300 people collapse or burned houses of 850 thousand and a Upgrade of seismic resistance of buildings : e.g. Upgrade ratio 75% -> 90% maximum economic loss of 112 trillion JPY are assumed. On the basis of the result, ‘General Secure household furniture : e.g. Fixation ratio 30% -> 60% Measures for Tokyo Metropolitan Earthquakes’ Improve crowded city blocks : e.g. Fire proofing ratio over 40% for each entity’s countermeasure in all of stages, Improve primary fire control ratio from prevention stage to post-earthquake stage. Measures for steep slope failure In metropolitan area, the core functions such as 【Disaster Reduction Objective】 government, administration, business are highly Reduce economic loss by 40% within next 10 years accumulated and a number of buildings and ・Wind 15m/s Approx. 112 → 70 trillion JPY population are concentrated. To secure the ・Wind 3m/s Approx. 94 → 60 trillion JPY continuity of capital functions such as politics, Business continuities by companies administration, business and economy function Restoration cost reduction measures in essential for the countermeasure of wide-area Restoring quick transportation network disaster emergency response crossing over prefectures should be solved when big Fig.6 Outline of Tokyo Metropolitan earthquake occurs in this area. Earthquakes Disaster Reduction Strategy

Figure 6 shows the outline of ‘Tokyo Metropolitan Earthquakes Disaster Reduction To execute emergency response activity Strategy.’ Disaster reduction goal such as to properly and rapidly by related organizations for halve the estimated death toll and to reduce the Tokyo Metropolitan Earthquakes, ‘Guidelines estimated economic loss by 40% in ten years is for Tokyo Metropolitan Earthquakes Emergency Response Plan’ which regulates the contents for earthquake intensity, within 30 minutes. The emergency activity, procedures and role for each result is offered to all of other ministries and this related organization is decided. This regulates information is considered useful and important contingency operation plan for all of for initial response just after the occurrence of organizations in disaster. earthquake. Figure 7 shows the result of The main contents are as follows; prediction of earthquake intensity distribution in 1) Priority for setting place of establishment of the Niigataken Chuuetsu Earthquake. emergency disaster management headquarter 2) Priority for setting place of establishment of Also, the ‘Disaster information sharing local emergency disaster management platform’ is now constructed. This system can headquarter integrate and see all of disaster information from 3) Act for maintaining business continuity for other ministries on the common map using GIS metropolitan function concept. Up to now, this platform is linked 4) Act for emergency rescue such as rescue, aid, with the system such as weather information, medical and fire-fighting activity, procurement seismic intensity information, river information of food and water, and securing traffic for and lifeline status information in metropolitan emergency transportation area and all of the information above can be visible. The increase of the contents in The discussion and the examination of detailed coordination with other ministries such as plan of activity are in progress for the Tokyo medical information, or satellite picture will be Metropolitan Earthquakes. continued. However, there are many problems to process this policy because the data in Massive number of evacuees and people disaster is difficult to maintain their accuracy stranded without a means of returning home is and security. estimated in this earthquake. In the general measures, the countermeasure is shown such as reducing evacuees to evacuation site, arrangement of evacuation system, secure of food, water and daily necessities, showing of proposal menu of emergency house and means of supporting evacuees. The measure for people stranded without a means of returning home, reducing the number of people’s returning to their home is shown. Concrete countermeasure for this is stated as the problem which should be solved in near future in the disaster reduction strategy, so the committees for technical investigation on evacuation measures and so on for the Tokyo Metropolitan Earthquakes is set in the CDMC and discuss the matters. Fig.7 Result of prediction of earthquake 3.6 Construction of Integrated Disaster intensity distribution in Niigataken Chuuetsu Management Information System Earthquake from DIS Preparing the concrete measure when disaster happens is also important. In Cabinet Office, the Disaster Information Systems is arranged. 4. CONCLUSIONS This system can estimate the number of death person and complete collapsed buildings The outline of the disaster mitigation policy in automatically on the basis of measured Japan was introduced in this paper. Large-scale earthquake may happen anytime, various areas. anywhere in Japan and everyone could have the damage from disaster. National people, 5. REFERENCES community, company and government have strongly tackled with measures for safety. The 1. Cabinet Office, Disaster Management in countermeasure against natural disaster will be Japan. 2007 accelerated by adding the knowledge from