Incorporating Science and Technology for Disaster Risk Reduction, – the Japanese Experience

NISHIKAWA, Satorua

a Vice-President, Japan Water Agency, Saitama, Japan, e-mail: satoru_nishikawa@water.go.jp

Abstract — Japan, throughout her history has long dealt with disasters, has recorded disasters, developed technologies to confront disasters. Even in recent two centuries when modern scientific observation was introduced, has accumulated experience of confronting with typhoons, earthquakes and tsunamis. Through these bitter experiences, Japan was prepared against strong M8 class earthquakes and tsunamis of 30 to 150 year return period. However the 11 March 2011 Great East Japan Earthquake was brought by a crustal movement far greater than the Jogan Earthquake 1100 years back in history. On the other hand, structural and non-structural earthquake countermeasures based on the experiences previous earthquakes have proven to be effective in earthquake disaster risk reduction. New technologies based on the latest scientific knowledge have proven its great value. These experiences are being shared with the international comunity and will be further shared on the occasion of the Third WCDRR in March 2015.

Keywords — disaster risk reduction, application of science and technology, HFA, Great East Japan Earthquake, typhoon, tsunami, post-2015 framework

1 Hazards Confronting Vulnerable Communities Cause Disasters

A typhoon hitting a no-man’s island is not a disaster. A strong earthquake in no-man’s desert is not a disaster. However if they hit squatters in low-lying areas, it will turn immediately into a disaster. Modern science still does not allow us to stop earthquakes nor diminish typhoons. However we can decrease the vulnerabilities of communities which may be affected by such hazards and thus reduce disasters (figure 1).

Figure 1: Hazards confronting vulnerable communities cause disasters
Table 1: Ranking of Earthquakes in 20-21st Century
Strong Earthquakes Deadly Earthquakes
Year Place Magnitude Year Place Casualties
1960 Chili 9.5 1976 China Tangshan 242800
1964 Alaska 9.2 1920 China Ningxia 235502
2004 Indonesia Sumatra 9.1 2004 Indonesia Sumatra 227898
2011 East Japan 9.0 2010 Haiti 222500
1952 Kamchatka 9.0 1923 Japan Kanto 105000
2010 Chili 8.8 2008 China Sichuan 87587
1906 Ecuador 8.8 2005 Pakistan, Afghanistan 86000
1965 Alaska Aleutian Islands 8.7 1908 Italy Sicily 82000
2005 Indonesia Sumatra 8.6 1927 China Gansu 80000
1950 Tibet, Assam 8.6 1970 Peru 66794
1957 Alaska Aleutian Islands 8.6 *
*
*
2011 East Japan 18498
Source: USGS and Cabinet Office Japan

The left half of Table 1 shows ranking of strong earthquakes in the 20th and 21st centuries. The right half shows ranking of deadly earthquakes. The two lists are quite different. It is a simplified indication of “hazards confronting vulnerable communities cause disasters”. The 1923 Japan Kanto Earthquake was magnitude 7.9 but it ranks 5th in number of casualties. In 1923, the Japanese seismic building standard was not adequate, Japanese cities were not well planned to prevent consequent urban fires, thus 105000 lives were lost. The March 2011 earthquake which hit east Japan ranked 4th in its strength. East Japan was an area with numerous cities, including the million city Sendai. However the casualties from this earthquake are far below on the list of deadly earthquakes. Japan has paid numerous efforts for disaster risk reduction, including the application of science and technology for reducing disasters. Nevertheless, casualty over 18000 was a shocking number. Further efforts are being pursued. The following describes how Japan has struggled to reduce disasters including through practical application of science and technology over the centuries.

2 Japan’s Long History of Struggling with Disasters

Japan, due to her location in the circum-Pacific “Ring of Fire” and in the Typhoon alley, has been menaced by numerous natural hazards; typhoons, floods, landslides, heavy snow, earthquakes, tsunamis and volcanic eruptions, throughout her course of history. Japan’s land count for 0.25% of the world, however Japan has the disproportionate share of 20.5% of all earthquakes stronger than M6 in the first decade of the 21st century and 7.0% of active volcanoes on earth. Due to these severe conditions, the Japanese have recorded disasters, have accumulated knowledge, have developed science and technologies to cope with disasters and thus have nurtured a culture of prevention.

2.1 The history of confronting disasters in pre-modern Japan

In the Nihon-Shoki, one of the oldest official history book edited in the 8th century, there are records of earthquakes and tsunamis. The Yamato-Kochi Earthquake on August 416 A.D. is reported and the Hakuho-Nankai Great Earthquake on November 684 A.D. and the subsequent great tsunami and land subsidence are reported. In the succeeding official history book, Nihon-Sandai-Jitsuroku edited in the 9th century, it is reported that on July 869 A.D., “a great earthquake hit the Mutsu-no-Kuni (the old name of Tohoku), toppled people were not able to stand up, houses collapsed and crushed to death, trapped in earth cracks, warehouses, gates, derricks and walls of fortresses were destroyed here and there, seawater surged to the castle of Taganoki and 1000 drowned to death”,(Sangawa, 2007) which describes that there was a similar gigantic earthquake & tsunami (the Jogan Earthquake) as the 2011 Great East Japan Earthquake & Tsunami.

In the history of Japan, there are many renowned historical figures who have contributed to disaster risk reduction. In the 6-10th century, Buddhism was brought to Japan from China through the Korean peninsula. Japanese priests were sent to China to acquire the Buddhist scriptures. They not only studied Buddhism but also acquired medical and civil engineering knowledge. Some of them strongly believed that alleviating the sufferings of fellow people was an important role of the religious leaders. Since the peasants at that time constantly suffered from droughts and floods, some priests stood up to apply their civil engineering knowledge for disaster risk reduction.

The high Buddhist priest Gyoki, in 7-8th century, on his road of missionary made civil engineering works for river control. In 731, Gyoki and his followers constructed Koya-ike (Koya-pond), a multi-purpose dam-reservoir for flood control and irrigation in the present Hyogo prefecture.(Kako and Ogata, 1997a) This Koya-ike is still used as tap-water reservoir, and is surrounded by a city park where the citizens enjoy the scenery. In 821, the high Buddhist priest Kukai (alias Kobo Daishi) reconstructed the Mannou-ike (Mannou-pond) dam reservoir by applying the latest civil engineering technology which is compatible to modern dams and saved the livelihood of farmers suffering from water shortage and flooding. This Mannou-ike is presently used as irrigation reservoir for 32 km2 of rice paddies in Kagawa prefecture Japan.

Figure 2: Shingen Tsutsumi (grouped echelon embankments)

The famous 16th century warlord, Takeda Shingen who had his main territories in the Kofu basin which was frequently menaced by violent flooding, newly developed water control levee work called Shingen Tsutsumi (grouped echelon embankments, figure 2) and also invented water control structure called Sacred Cow (lumber made triangular pyramid to be placed in riverbeds of torrents to streamline and ease the flow), thus stabilized the livelihood of his farmers and gained support and power.(Kako and Ogata, 1997b) All of these figures contributed to the welfare and livelihood of commoners by development and application of disaster risk reduction technologies and are regarded as the great saviors in Japanese history.

2.2 The culture of disaster prevention fostered in Japan

Through these bitter experiences Japanese people have fostered a culture of disaster prevention. This is reflected in the traditional listing of dreadful things for Japanese children “Jishin Kaminari Kaji Oyaji” which means “Earthquake, Thunder, Fire and Father (Storm)”. Oyaji which stands for a strict father in normal Japanese also stands for a big storm. There are numerous local legends and proverbs expressing the necessity to be prepared for disasters.

One example is the story of “Inamura-no-hi, Fire on Rice Sheaves” based on the immediate tsunami evacuation led by the Hiro village chief Hamaguchi Gihei right after the 1854 Ansei-Nankai Earthquake. Hamaguchi felt a strong earthquake and when he was looking down from hilltop, he found that the seawater was receding and noticed that this was the sign of a tsunami coming. Since it was getting dark, Hamaguchi having a quick wit, he lit fire on stacks of harvested rice sheaves on the high grounds. His fellow villagers were surprised to see the fire and ran up the slopes to extinguish the fire. Hamaguchi ordered them to let the fire burn on so that their followers will continue to run up the slopes, thus enabling them to flee from the tsunami. When the villagers looked back, their houses facing the seashore were totally inundated. Seeing the devastation by the tsunami, Hamaguchi stood up for the reconstruction of the village and provided funds for construction of a tsunami embankment along the coastline and hired the villagers who lost their means of living. This story was published in the national elementary school reading book from 1937 to 1947 and is widely known among the Japanese population. This tsunami embankment protected the Hiro village in 1946 when the Showa-Nankai Tsunami hit again.(Japan Meteorological Agency, 2014)

Another is a proverb said by a famous physicist Torahiko Terada who investigated the 1923 Great Kanto Earthquake, “Tensai ha wasuretakoro ni yattekuru: Natural hazards will hit us when we have forgotten about it” alerting us of the importance of disaster awareness. Furthermore, every time a large disaster hit, people would erect stone monuments and shrines to pass down the bitter experiences to their descendants. When Edo (the old name of Tokyo) was hit by the Ansei-Edo Earthquake in 1855, a Ukiyo-e (a popular woodblock color print of Edo era) drawing was published, showing the citizens of Edo, trying to beat the legendary monster catfish which at that time was believed to have caused the earthquake (figure 3). This drawing symbolizes the wish of the Edo commoners to eliminate earthquakes. These form an important part of the Japanese culture and are still occasionally used in public awareness programs.

Figure 3: Traditional Ukiyo-e drawing “Shin-Yoshihara Oo-Namazu Yurahi”

Even in the modern age, disasters have continued to ravage Japan. In 1891, 7273 people were killed by the M8 Noubi Earthquake; in 1896, 22000 lost their lives in the Meiji-Sanriku Tsunami, and in 1923 Tokyo and its vicinity was devastated by the M7.9 Great Kanto Earthquake. This latter disaster resulted in the loss of 105000 lives and 40% of the country’s GDP. In 1933, 3064 people were killed by the Showa-Sanriku Tsunami. In response to the devastating damage, the Japanese government not only provided relief and recovery to the affected areas but also tried to investigate the root causes of these damages through the inter-disciplinary Association for Earthquake Disaster Prevention, established in 1892. The association continued its activities until 2010 when its responsibilities were handed over to the Japan Association for Earthquake Engineering.

3 Institutionalization of Disaster Risk Reduction Efforts in Modern Japan

3.1 Typhoons threatened peoples’ lives in 1940s and 50s

In the 1940s and 50s Japan was repeatedly ravaged by typhoons and earthquakes. Almost every year, thousands of lives were lost by typhoons(see table 2). In response, Japanese government incrementally placed measures to cope with disasters.

Table 2: Casualties by series of typhoons in 1940s and 50s
Year Typhoon Death Toll
1945 Makurazaki Typhoon 3756
1947 Catherine Typhoon 1930
1948 Ion Typhoon 838
1950 Jane Typhoon 539
1951 Ruth Typhoon 943
1954 Toyamaru Typhoon 1761
1958 Kanogawa Typhoon 1269
1959 Ise-wan Typhoon 5098

3.2 The first epoch-making turning point 1959 Ise-wan Typhoon

In 1959, when Japan was on her course of revival from the ashes of World War II, Ise-wan Typhoon hit the third largest metropolitan area Nagoya and killed 5098 people. Ise-wan Typhoon was a category 5 super typhoon, with its lowest pressure at 895hpa and maximum wind speed of 75m/s. It brought not only havy rainfall of 650mm/day but also the strong wind generated an enormouse storm surge and inundated the low lying areas of Nagoya and its vicinity where three major rivers assemble to flow into Ise bay.

This heavy damage triggered a big debate in the Japanese government on how to cope with natural hazards. After two years of debate, the Disaster Countermeasures Basic Act was legislated in 1961. This Act has three major characteristics.

  • The Central Disaster Management Council, chaired by the Prime Minister and with membership of all Ministers of the Government as well as heads of semi-public organizations, such as NHK Public Broadcasting, Bank of Japan, Japanese Red Cross and the NTT Telecommunications Company as well as representatives of Academia. This Council was given the role of formulating the overall policy for disaster risk management and functioned as the national coordinating body for disaster management.
  • The roles and responsibilities of the National, Prefecture and Municipal Governments as well as community organizations and citizens regarding disaster risk reduction were clearly defined and the three layers of governments were obliged to make their master plans for disaster risk reduction. Also all the Ministries and semi-public sectors, such as electricity, gas, railway, bus and forwarder companies were obliged to make their sectoral disaster management plans.
  • The Cabinet must submit annual official report to the National Diet, regarding the status of disaster risk management and the budgetary allocations to disaster risk reduction programs. The National Diet, both in the lower house and the upper house formed a special committee for disaster management, have continued to monitor governmental efforts for disaster risk reduction. Hence, even in years when no major disaster occurred, disaster risk management was always put on the national political agenda, and thus mainstreamed disaster risk reduction in the national policy and as a result, helped in securing the stability of financial basis for disaster risk reduction.

This Basic Act proved to be quite effective in addressing not only the emergency response but also prevention/mitigation, preparedness and recovery/reconstruction, all the four phases of disaster risk reduction through a multi-sectoral approach. In addition, in 1960, “the Erosion and Flood Control Emergency Measures Act” was legislated to enhance preventive works, in 1962, “the Act Concerning Special Financial Aid to Deal with Disaster” was legislated to assist local governments for recovery. (Nishikawa, 2007)

Figure 4: Number of casualties by natural disasters in Japan 1945-2013, source Cabinet Office

Furthermore, this Basic Act was effective in calling for pre-disaster investment. Based on the bitter lessons of Ise-wan Typhoon, Japan Meteorological Agency decided to mount a meteorological radar on top of Mt. Fuji, the highest (3776 meters) & single peak mountain of Japan which makes it ideal location for long range radars. Mt. Fuji radar started operation in 1964, covering 800km radius. A large scale dam was planned in the upstream of Ibi river, one of the three major river flowing into Ise bay to prevent flooding of Nagoya and after decades of negotiations for local concensus, Japan Water Agency constructed the Tokuyama Dam in 2008. Tokuyama Dam has a reservoir capacity of 660 million tons and is the largest dam in Japan and is capable of storing a full rainfall of a typhoon in its upstream 245km2 basin area and thus protect its downstream Nagoya.

In addition, 1 September, the day Tokyo was devastated by the Great Kanto Earthquake and also the day which the typhoons are most frequent to land on Japan, was designated as “Disaster Prevention Day” in 1960 and hence, every year, public awareness programs for disaster risk reduction are conducted.

Another significance of the the Disaster Countermeasures Basic Act was the organization of the Central Disaster Management Council, where the incorporation of latest scientific & technical knowledge for disaster risk reduction was institutionalized. The Central Disaster Management Council will always have representatives of the scientific community in its main council, as well as to invite various scientists and practitioners in its sub-committees. Whenever there is a major problem in addressing disaster risk reduction is newly identified, a special sub-committee will be organized inviting various scientists and practitioners relevant to the new issue. This setting enables to reflect the latest scientific and technological knowledge into policy formulation.

With these efforts, although the number of typhoons attacking Japan has not changed in average over the last 70 years, the number of casualties by natural disasters has greatly decreased (figure 4).

4 Challenges of Earthquake Disaster Risk Reduction in Modern Japan

4.1 Earthquakes, another threat to Japanese people

Since the Japanese archipelago is located in the boundaries of three tectonic plates, the Eurasia, the Pacific and the Phillipines plates, it is frequenly hit by earthquakes and tsunamis. Table 3 shows the list of earthquakes and/or tsunamis between 1945 and 1995. The three earthquakes in 1945, 1946 and 1948 were deadly, claiming thousands of lives by collapsed houses and subsequent urban fires.

Table 3: Casualties by earthquakes & tsunamis 1945-1995
Year Earthquake Magnitude Death Toll
1945 Mikawa Earthquake 6.8 2306
1946 Nankai Earthquake 8.0 1330
1948 Fukui Earthquake 7.1 3769
1952 Tokachi-oki Earthquake 8.2 33
1960 Tsunami by Chile Earthquake (9.5) 139
1964 Niigata Earthqauke 7.5 26
1968 Tokachi-oki Earthquake 7.9 52
1974
Izu-hanto-oki Earthquake
6.9 30
1978
Izu-Oshima Kinkai Earthquake
7.0 25
1978 Miyagi-ken-oki Earthquake 7.4 28
1983 Nihonkai Chubu Earthquake & Tsunami 7.7 104
1984
Nagano-ken Seibu Earthquake
6.8 29
1993
Hokkaido Nansei-oki Earthquake & Tsunami
7.8 230
1995
Hanshin-Awaji (Kobe) Earthquake
7.3 6436

Every time these earthquake brought havoc, thorough scientific investigation on the causes of the destruction to houses and buildings were made. Seismic building standards were revised based on these findings. Table 4 shows the list of major earthquakes which triggerred these revision. The 1968 Tokachi-oki earthquake and the 1978 Miyagi-ken-oki earthquake showed serious structural damage to modern RC and SRC buildings. In 1981, based on these findings, the Building Standard Law was fully revised to make buildings meet the following requirements;

  • No damage aginst medium scale (80-100 gal ground motion) earthquakes,
  • To be able to continue use after these medium earthquakes,
  • No collapse & safety of people inside against large scale (300-400 gal ground motion) earthquakes.

This 1981 revision, later showed its significance when Kobe was hit by a major earthquake in 1995.

Table 4: Earthquakes which brought major evolution of Japan’s anti-seismic building code
Year Earthquake Magnitude Casualties Sesmic building standards
1923 Great Kanto M7.9 105000
1924 First Seismic Building Code
1948 Fukui M7.1 3769
1950 Building Standard Law
1968 Tokachi-oki M7.9 52
1978 Miyagi-ken-oki M7.4 28
1981 Revision of Building Standard Law

4.2 The second epoch-making turning point 1995 the Great Hanshin-Awaji(Kobe) Earthquake

Early in the morning of 17 January 1995, a strong M7.3 earthquake hit the City of Kobe and its vicinity. The epicenter was shallow, approx. 12km in depth; the active fault ran directly beneath the center of Kobe. This is called the “the Great Hanshin-Awaji Earthquake”. The collapse of buildings and subsequent fires killed 5521. The total number of casualties, including indirect deaths tolled to 6437. This was the worst natural disaster for Japan since the 1959 Ise-wan Typhoon. The sixth floor of Kobe city hall building was crushed, the Hyogo prefecture Government building was cracked. Local fire and police stations were heavily damaged, local city offices which were designated as emergency command stations also damaged and lost electricity, thus paralyzing the initial local Government response command for a few hours. The passable roads in Kobe were jammed with cars, since the initial traffic control was not strictly enforced, thus delaying ambulance and firefighters. The bottom up damage reporting system formed in 1961, from municipal Government to prefecture Government and then to National Government, also the three layered response system, first the municipal Government, then the prefecture respond at the request of the mayor, then at the request of the governor the national Government respond, did not function, since the initial responders themselves lost base and were not able to grasp the entire damage. Later in the morning, when the daylight came, the aerial footage from NHK (the public broadcasting TV) helicopter showed serious damage, however the casualty reports from local Governments to Tokyo counted for less than 100, which showed the malfunctioning of the reporting system.(Nishikawa, 1995)

The Hanshin-Awaji Earthquake was the first major natural disaster to hit the center of a large modern metropolis, and revealed the weaknesses of the 1961 system. Numerous lessons were learnt from this earthquake. The Japanese Government thoroughly reviewed the Disaster Countermeasures Basic Act and made a major revision in 1995 mainly focusing on the immediate response system. For example, if in case of a major disaster and if the Prime Minister sees that the damage is overwhelming the capacity of the local Government, he can immediately mobilize the national defense force without the request from the governor. The Prime Minister is also given the power to create an on-site emergency coordination headquarters and designate the head. New decision supporting systems, damage estimation systems, emergency communication systems, using GIS and latest IT tools were developed. Whenever a strong earthquake was observed, the damage estimation system would be automatically activated to determine the scale of the human casualties and building damage to give guidance to the immediate response.

New research programs for earthquake science were launched. Nationwide investigations of active faults were launched and the results were published as a map. It showed that all 47 prefectures of Japan have active faults and urged all local Governments to be aware of this fact and revise their local disaster management plans accordingly.

Institutional arrangements for disaster management were enhanced. A new high ranking position, Deputy Chief Cabinet Secretary for Crisis Management was created. In January 2001, on the occasion of National Government Reform, a new position, Minister of State for Disaster Management was created in the Cabinet Office to be in charge of inter-ministerial planning and coordination. The Minister would act on behalf of the Prime Minister who is the chair of the Central Disaster Management Council and is the advocate for disaster risk reducton at the political level and will be the controller and coordinator of the response. This Minster’s presence upgraded the status of disaster risk reducton policy at the national level.

4.3 New initiatives for public awareness launched

Prior to the 1995 Earthquake, many Japanese believed that, it would be the Tokai (the area between Tokyo and Nagoya) and the Tokyo Metropolitan areas which would be hit by major earthquakes in the near future. Especially the citizens of Kobe erroneously believed that they do not face the risk of earthquakes, simply because they have not experienced small earthquakes in their living memory. However, the lifetime of human beings is far shorter than the recurrence period of extreme natural events. Therefore it is absolutely necessary to inherit the lessons learnt from disasters over the generations and also to share them across geographical boundaries.

The Disaster Reduction and Human Innovation Institution (DRI) was newly organized by the Hyogo Prefectural Government with the financial and technical support from the Cabinet Office and opened in April 2002 together with its museum facility in Kobe, with the aim to meet such necessity, in particular to hand down the experience of the Great Hanshin-Awaji Earthquake to younger generations and best use the lessons learned from the Earthquake in future disaster management initiatives. DRI commits itself to create a disaster management culture, improve local capacities for disaster risk reduction, support planning of disaster management policies and help realize a safe and secure community in which citizens work together for disaster risk reduction. DRI also aims to play a pivotal role in developing and disseminating effective and overall countermeasures against disaster, and to serve as a center for research and study of disaster risk management. When a disaster occurs, DRI’s researchers are dispatched to the affected areas to support the local government and offer their disaster management methodology. DRI museum exhibits the devastation by the Earthquake, the sufferings of the people and the reconstruction process. The Earthquake survivors are always available at the exhibition space as volunteers to explain their own personal experiences to the visitors with their own words. DRI has become one of the most popular site visits for junior high school excursions.

In May 2003, for the sake of extracting valuable lessons from historical disasters, the Central Disaster Management Council decided to commission the Special Committee on Inheritance of Lessons Learnt from Disasters to thoroughly review historical disasters from inter disciplinary viewpoints. Academicians from different sciences were convened and mobilized for acquisition of dispersed historical documents on selected individual disasters from 17th to 20th century in Japan and to review them from various perspectives to draw the entire picture of the damage and human response to each disaster. By December 2010, a total of 24 disasters were reviewed and reports on individual disasters, as well as analytical reports on lessons by type of disaster; hydro-meteorological, volcanic, ocean-tectonic earthquake & tsunami, inland earthquake, urban fires, were published. Also educational materials for child and adult education were produced and posted on the Cabinet Office website to be freely used for various public awareness programs.(Cabinet Office of Japan, 2014)

4.4 The improved disaster management system tested in Japan

A major volcano in Hokkaido, Mt.Usu erupted in 2000 to 2001, on-site emergency coordination headquarters was placed, the scientific prediction of lava and ash flows and the local evacuation plans were thoroughly linked at the headquarters. Massive orderly evacuation of residents was successful and resulted in no human casualties.

In May 2003 a strong M7.1 earthquake hit Miyagi in northern Japan, but there were no casualties. Disaster information was immediately shared among local and national authorities. Miyagi was hit again by M7.2 earthquake in August 2005, again with no casualties. Miyagi was previously hit by M7.4 earthquake in 1978 and 28 people were killed. These three earthquakes in Miyagi demonstrated the progress in disaster risk management in Japan and also alerted people in Miyagi to be prepared for future strong earthquakes (Table 5).

Table 5: Comparison of 3 earthquakes which hit Miyagi prefecture
12 June 1978 26 May 2003 16 August 2005

magnitude

7.4 7.0 7.2
focal depth 40km 71km 72km
max. JMA seismic intensity 5 6 lower 6 lower
deaths 28 0 0
injured persons 1325 174 91
collapsed houses 1183 2 1
half-collapsed houses 5574 21 0
partially damaged houses 60124 2342 856

4.5 Earthquake disaster risk reducton strategy for Japan

The series of research programs for disaster risk reducton and the enhanced institutional arrangements following the 1995 Hanshin-Awaji Earthquake brought new findings and policies. Starting from 2003, the Central Disaster Management Council published series of detailed damage estimates for probable major earthquakes, Tokai, Tonankai & Nankai, and Inland Tokyo earthquake. All of these estimates indicated that the damages will be far more serious than the Kobe earthquake. Countermeasures to decrease the damages were sought. Detailed investigation on the causes of death cases in Kobe earthquake revealed that 80% of the deaths were brought by physical collapse of houses and falling furniture, and their majority died within 15 minutes after the quake. This fact indicated that no matter how quick the rescues teams were mobilized, it would have been difficult to save many lives. Houses built before the 1981 building code suffered heavy damage, whereas new houses had slight damage. These facts led to clear conclusion, in order to substantially decrease casualties, preventive measures are much more important than response. Old buildings need to be structurally checked and retrofitted as necessary. Based on these findings, the Central Disaster Management Council decided the Earthquake Disaster Reduction Strategies for Tokai, Tonankai & Nankai, and Inland Tokyo earthquakes. These strategies are comprised of set of menus for action to effectively halve the estimated damage of major earthquakes in ten years. For example, Inland Tokyo Earthquake Strategy lists 5 main pre-disaster menus to halve death casualties:

  • Seismic strengthening of housing and building stocks,
  • Affixing of furniture,
  • Redevelopment of old densely populated area,
  • Upgrade immediate fire extinguishing capacity,
  • Protect steep hill from failures; and 3 main menus to halve economic damage:
  • Mitigation measures to decrease reconstruction costs,
  • Business continuity of enterprises,
  • Early recovery measures for transportation facilities.

4.6 Implementing HFA in Japan, Nationwide movement for disaster risk reduction

In 2004, Japan was hit by a record breaking number of 10 typhoons. In October 2004, a strong earthquake hit Niigata in northern Japan. Thus the year 2004 was named as the “Year of Disasters” in Japan. The December 2004 Indian Ocean Tsunami reminded the threat of possible tsunamis by Tokai and Tonankai & Nankai earthquakes in Japan. The set of menus listed in the Earthquake Disaster Reduction Strategy required full government commitment to halve the estimated damage in 10 years. In addition, certain menus require strong voluntary action of the private sector and the public at large. Following the success of the UN World Conference on Disaster Reduction in January 2005, where the Hyogo Farmework for Action was adopted, the Government of Japan decided to take this opportunity to reinforce disaster risk reducton activities as the implementation of HFA in Japan. In July 2005, the Central Disaster Management Council commissioned its subcommittee to launch the Nationwide Movement for Disaster Reduction.

In 2006 the government increased subsidies and tax incentives for seismic retrofitting of houses. However, the house owner must recognize his own risk of being killed by his house and take his own initiative to invest for his safety and to apply for subsidies and tax exemptions. It is up to the resident to decide on affixing his furniture. The CEO of an enterprise must recognize the significance of business continuity planning for his own sake. New disaster awareness activities involving various sectors and groups; chambers of commerce, parents & teachers associations, Red Cross chapters, local shop unions, were proposed. Public awareness programs and educational materials were developed. Comic books by renowned artists were published. A movie based on a real story of the Kobe earthquake was produced and ranked third in December 2006 national ticket sales.

Special focus was given to the involvement of the business sector in disaster risk reducton activities for 3 reasons; companies need to secure the safety of their employees and customers in their premises, companies need to act as good neighbors in case of emergencies, business continuity is critical to minimize economic damage. The Central disaster management council published the Business Continuity Guidelines 1st edition in 2005 where the concept of Business Continuity Planning is thoroughly defined and elements are described(see Ref.13). Furthermore, the council called on trade unions to adapt this guideline to the specific characteristics of each industry. The Government, in association with the Development Bank of Japan, newly offered special low interest loans to companies which fulfill the basic points of the BC Guidelines. In addition, with the endorsement of the Cabinet Office, BCAO (Business Continuity Advancement Organization) was established in 2006 to widely disseminate BCP in Japan.

Through these activities, “disaster reduction is everyone’s business and should not be limited to emergency managers” started to be widely accepted in Japan.

5 The Great East Japan Earthquake & Tsunami, the Third Epoch

At 14:46 JST on 11March 2011, a gigantic earthquake of Mw9.0 with its hypocenter at longitude E142.9, latitude N38.1, (approximately 130km off to the east of Tohoku Japan) depth 24km, occurred. This earthquake was a gigantic ocean-tectonic earthquake, generated on the plate boundary of the Pacific and the Continental plates. The earthquake source region stretched from off Iwate to off Ibaragi in the Pacific, and it is estimated that a gigantic fault, 200km wide and longer than 450km, ruptured with a maximum slide of 20 to 30 meters. The fault rupture started with its epicenter in the off Miyagi Pacific and propagated north to off Iwate and south to off Fukushima & Ibaragi. It is estimated that this rupture propagation continued for 3 minutes. This resulted in the movement of the seabed for 24meters horizontal and 3meters upward and thus generated a gigantic tsunami.

Seismic intensity level was measured as 7(maximum on JMA scale) in northern Miyagi, a vast area of 34843km2 (9.2% of the Japanese land) in eastern Japan was shaken at a strength more than 5+ on seismic intensity level. Center of Tokyo observed 5+. Almost the entire Japanese archipelago, from Hokkaido to Kyushu was shaken by this earthquake. The shaking lasted very long, in Sendai the strong shaking (stronger than 3 on seismic intensity level) lasted for 9minutes 40seconds, in Oofunato 7minutes 50seconds, in Chiyoda-ku Tokyo 6minutes 40seconds. This strong lasting shake caused liquefaction in numerous places in East Japan where the groundwater level was high. Furthermore, strong aftershocks repeated, at 15:08 on 11 March M7.4, at 15:15 on 11 March M7.7, at 15:25 on 11 March M7.5, at 23:32 on 7 April M7.1, at 17:16 on 11 April M7.0. In addition, the gigantic earthquake induced additional earthquakes in distant locations, on 12 March M6.7 in northern Nagano and on 15 March M6.4 in eastern Shizuoka.

This was the strongest earthquake observed in Japan’s history and was the 4th strongest earthquake observed by modern science in the 20th & 21st century. The consequent tsunami claimed 18498 lives, brought massive destruction to the Pacific coastline of northeastern Japan. Also the very strong and long shaking caused widespread damage to industries. The strength of this earthquake was almost equivalent to the North Sumatra Earthquake, which generated the Indian Ocean Tsunami, claiming the lives of 227898 in December 2004.

5.1 Earthquake early warning and tsunami warning

8.6 seconds immediately after the start of the earthquake, Japan Meteorological Agency (JMA) issued Earthquake Early Warning (EEW) to Iwate, Miyagi, Fukushima, Akita and Yamagata Prefectures.

JMA provides residents in Japan with Earthquake Early Warnings. This is a new system launched on 1 October 2007, which issues prompt alerts through a number of media outlets such as TV, radio and mobile phones, just as an earthquake starts, providing valuable seconds for people to protect themselves before strong shakings arrive. When earthquake occur, primary pressure (P) wave and secondary shake (S) wave propagate through the earth. There is a speed difference between the P and S waves. P wave travels faster than the S wave. The S wave causes the physical damage to structures. EEW system provides advance announcement of the estimated seismic intensities and expected arrival time of principal shake motion. These estimations are based on prompt analysis of the focus and magnitude of the earthquake using wave form data observed by seismographs near the epicenter. The EEW is aimed at mitigating earthquake-related damage by allowing countermeasures such as promptly slowing down trains, controlling elevators to avoid danger and enabling people to quickly protect themselves in various environments such as factories, offices, houses, and near cliffs.

This EEW alert gave 5 seconds advance warning to Oshika Peninsula in Miyagi, which was the nearest land to the epicenter. 10 to 15 seconds advance warning to Sendai. 60 seconds advance notification to people in Tokyo which was 360km away from epicenter, that there is a major earthquake occurring in Tohoku. People were alerted through NHK (public broadcasting station in Japan) TV & radio, and mobile phones that a strong shake is coming.

At 14:49, 3minutes after the start of the earthquake, based on the initial seismic observation, JMA issued Major Tsunami Warning (tsunami higher than 3meters expected) to the Pacific coast from Iwate to Fukushima, Tsunami Warning to Aomori, Ibaragi and Chiba, Tsunami Advisory to other Pacific coastal areas ranging from Kuril Islands in the north to Amami Islands in the south was issued. This initial tsunami prediction estimated 3meters tsunami in Iwate and Fukushima, 6meters in Miyagi. Then, upon receipt of the tsunami wave height propagating towards land caught by the GPS buoy tide gauge installed off the coast of Iwate, at 15:14 JMA upgraded the tsunami warning. Major Tsunami Warning was expanded from Aomori to Chiba, tsunami height prediction raised to 6meters in Iwate and Fukushima, 10meters in Miyagi.

5.2 Arrival of the tsunami

The tsunami generated by the gigantic earthquake, repeatedly surged mainly to the Pacific coasts from Hokkaido to Chiba, but also as far as to Okinawa and Ogasawara Islands and even to the Japan Sea coasts. The highest tsunami level observed at JMA’s tide stations were 9.3meters+ at Souma Fukushima (at 15:51 on 11March), 8.6meters+ at Ishinomaki Miyagi (at 15:25 on 11 March), 8.5meters+ at Miyako Iwate (at 15:26 on 11March). However due to destruction of the tide station by the first tsunamis, there are possibilities of missing observations of consequent higher tsunamis. JMA later surveyed traces of tsunami along the coasts and estimated the highest to be 16.7meters at Oofunato Iwate. Furthermore, a high tsunami run-up more than 40meters was observed in Miyako Iwate.

A strong earthquake and consequent tsunami off the coast of northeastern Japan was not a surprise; scientists have warned of such possibility and the Japanese Government had made assessments of possible damage. But Mw9.0 was one scale larger than what was expected. However, the culture of prevention and the institutional arrangements fostered over the years through bitter experiences of natural disasters in Japan have contributed to reducing the damage. Early warning systems, seismic reinforcement of houses & critical infrastructures, and automated safety mechanisms for Shinkansen bullet trains, were effective in minimizing casualties from the earthquake.

5.3 Pre-assessment and preparedness against tectonic earthquake & tsunami

The Pacific coast of Tohoku has repeatedly experienced tsunamis, in 1896 Meiji-Sanriku Tsunami (M8.3, 22000 casualties), in 1933 Showa-Sanriku Tsunami (M8.1, 3064 casualties), in 1960 Chili Earthquake Tsunami (M9.5, 142 casualties by the tsunami which propagated from Chili). Recent earthquakes were 1978 June Miyagi-ken-oki (M7.4, 28 casualties), 1994 December Sanriku-haruka-oki (M7.6, 3 casualties), 2003 May Miyagi-ken-oki (M7.1, no casualties), 2003 September Tokachi-oki (M8.0, 2 casualties in Hokkaido), 2005 August Miyagi-ken-oki (M7.2, no casualties).

Alerted by these, in April 2004, the Japanese Government legislated “Act on Special Measures concerning Advancement of Countermeasures against Earthquake Disaster in Relation to Subduction Zone Earthquake around Japan Trench and Chishima Trench” and designated 119 municipalities in Hokkaido and Tohoku Pacific coast as the special zone to promote earthquake preparedness. The Central Disaster Management Council published the pre-assessment of estimation of seismic ground motion and tsunami in June 2005. In this pre-assessment, 8 types of earthquakes with evidence of clear repetition, were set as the target earthquakes. The damage pre-assessment for the 8 target earthquakes and tsunamis were published in January 2006. It indicated that, for example, in the case of M8.6 Meiji-Sanriku type, tsunami will surge to the long coastline ranging from Aomori to Chiba and may result in 2700 casualties, in the case of M8.2 scale earthquake off Miyagi coast, 21000 buildings may collapse. In December 2008, the Earthquake Disaster Reduction Strategic Policy to substantially reduce such damage in 10 years was formulated. Based on this policy, seismic retrofitting of houses and buildings, construction of shore protection facilities and mapping & distribution of tsunami hazard maps were promoted. However, the actual magnitude and the source zone of 11 March Great East Japan Earthquake and Tsunami was far larger than any of the 8 targets, since it was an unexpected multiple conjunction of the target earthquakes. The actual tsunami inundation area was twice as large as the pre-assessed maximum of 270km2.

In March 2005, an estimate that the probability of earthquake occurrence off Miyagi coast within the next 30 years would be 99% was published by the Ministry of Education, Culture, Science and Technology. The City of Sendai, which is the largest city in Tohoku with a population over 1 million, was predicted to experience violent ground motion. Therefore, the city with the cooperation of the Cabinet Office, organized a large earthquake disaster prevention expo in September 2005 to publicize to her citizens the importance of earthquake preparedness. In April 2008, the city formulated the plan for promotion of seismic retrofitting in Sendai, and in accordance with this plan, provided diagnosis service of earthquake resistance of houses and subsidies for seismic retrofitting.

In the 1995 Hanshin-Awaji (Kobe) Earthquake, the elevated rail tracks of Sanyo Shinkansen and the elevated highway fell down. Based on this bitter experience, the seismic engineering standard for road bridges was revised in 1996 and 2002. By 2003, out of the 50900 bridges on the important designated emergency transport routes, 45900 were retrofitted. And by 2008, the number of such bridges which were left to be retrofitted decreased to 2000. Seismic engineering standard for railways was revised in 1998. Based on this revision, seismic reinforcement of elevated tracks, bridges, supporting pillars and the tunnels of Shinkansen and main artery lines were promoted.

5.4 The effectiveness of seismic enforcement of buildings and transportation facilities

The shaking by this earthquake was far longer, stronger and wider than the 1995 Hanshin-Awaji (Kobe) Earthquake. However the casualties by structural collapse were very limited compared to 1995. The majority of damage to houses was from tsunami inundation. The City of Kurihara in Miyagi, located inland, observed the strongest ground motion of JMA seismic intensity 7, but there was no casualties, not a single house caught fire by collapse. The City of Sendai observed strong ground motion of seismic intensity 6+ and 6-, no office building collapsed, only 1% of office buildings suffered partial damage such as gaps in the entrance steps or tilted signboards. Out of the 1642 large condominium buildings in Tohoku, not a single building suffered serious structural damage, compared to the 1995 earthquake where 1.6% of the condominium buildings in the affected area suffered serious structural damage. Also the new base seismic isolation buildings proved its value in substantially decreasing the shake inside the building. The anti-seismic preparations against M8 earthquake proved to be effective for M9 earthquake.

5.5 Automated technologies saved lives

The Japanese Shinkansen Bullet Trains are equipped with Early Earthquake Detection System. Seismographs are placed along the shoreline and along the rail lines to detect the preliminary tremors by the primary P wave. Once detected, this system will automatically cut the power supply and activate emergency brake, and speed down the train before the main shake by the secondary S wave. In the case of the 2004 Niigata-Chuetsu Earthquake the system worked for the Joetsu Shinkansen, passengers were safe but several cars derailed. Therefore JR East Company who runs the Joetsu and Tohoku Shinkansen upgraded the system. On 11 March 2011, when the earthquake occurred, 27 Shinkansen trains were running, 2 were running near Sendai at their maximum speed of 270 km/h. The system was triggered, power was cut 9 to 12 seconds before the arrival of the first shake, emergency brake activated, 70 seconds later the main shake came, since the trains were slowed down to 100km/h, safely stopped, no derailments, no injuries to passengers on board (figure 5). Also, thanks to the seismic reinforcement of elevated rail tracks and bridges, none of them collapsed.

Figure 5: Shinkansen Earthquake Early Detection System

All the households in Japan which have city gas service are equipped with micro-chip controlled gas meters which will automatically shut down gas flow when an earthquake stronger than seismic intensity of 5- is detected on the site. On 11 March these meters immediately stopped gas flow to each household and also the Sendai City Gas Service stopped all supplies from their gas factories. Therefore Sendai was saved from large scale fire spread from earthquake. The bitter lessons of large scale fire in Kobe in 1995 earthquake were reflected.

5.6 Tsunami preparedness education saved the lives of the youth

In line with the Nationwide Movement for Disaster Reduction, the Ministry of Education, Culture, Science and Technology in 2008 initiated a new program to encourage development of effective disaster education programs and called on universities and disaster research institutions for application. The City of Kamaishi in Iwate Prefecture together with Gunma University proposed to develop an effective tsunami awareness and evacuation program for students and pupils. Kamaishi had been menaced by the 1896 Meiji-Sanriku and 1933 Showa-Sanriku Tsunami and furthermore was being warned of a possible M8 earthquake & tsunami in the near future. In March 2010, the “Manuals of Kamaishi Tsunami Preparedness Education” was published. Based on this manual, all the elementary and junior high schools in Kamaishi were trained following a proactive program designed by Gunma University, to act immediately and evacuate to safe grounds as first leaders of evacuation. They were shown the live footages of the 2004 Indian Ocean Tsunami and understood the necessity to be ready for the worst case scenario.

When the Great East Japan Earthquake & Tsunami hit Kamaishi on 11 March 2011, although the inundation in the City of Kamaishi was far broader than what was previously shown on the Kamaishi Tsunami Hazard Map, the 3000 pupils and students at school all evacuated safely to high grounds. In the case of Kamaishi Higashi Junior High School, the students, on their way of evacuation, guided the near-by elementary school pupils hand in hand and ran to safe high grounds. This is known as the “Miracle of Kamaishi” and demonstrated the effectiveness of tsunami preparedness education programs and saved the precious lives of the youth.

6 Sharing the Lessons from the Great East Japan Earthquake & Tsunami and towards the Post-2015 Framework for Disaster Risk Reduction

Japan was prepared against strong M8 class earthquakes and tsunamis of 30 to 150 year return period. However the Great East Japan Earthquake & Tsunami was brought by a crustal movement greater than the Jogan Earthquake 1100 years back in history. It is truly regretful that the latest scientific investigation on tectonics of Japan Trench was not advanced enough to caution with satisfactory scientific evidence, the probability of M9 class earthquake. Nevertheless, structural and non-structural measures based on the lessons of the successive earthquakes in Japan have proven to be effective in disaster risk reduction. New technologies such as the Earthquake Early Warning and seismic base isolation structure have proven its great value. The Central Disaster Management Council immediately commissioned a special Committee for Technical Investigation on Countermeasures for Earthquakes and Tsunamis to draw lessons. Based on the findings of this committee, the Disaster Countermeasures Basic Act was revised twice, in June 2012 and June 2013. One of the pillars of the revision was to institutionalize the inheritance of local disaster lessons and to make compulsory the organization of disaster education by all of the heads of local government organs and managers of important facilities. Furthermore, detailed investigations on causes of casualties and various damages are undertaken by all of the relevant governmental agencies and academic institutions. Numerous new lessons are being revealed.

The Japanese Government was swift in deciding to share the lessons with the international community. In May 2011, only two months after the earthquake & tsunami, on the occasion of the Global Platform for Disaster Risk Reduction, the Vice Minister for Disaster Management expressed the Japanese Government’s will to host the next UN world conference in 2015 so as to share the lessons learnt. The World Bank, together with the Japanese Government, launched a comprehensive study project “Learning from Mega-disasters” in 2011 to draw the lessons for the international community and compiled the detailed “Knowledge Notes” in 2012. The World Bank organized series of in-country workshops around the world, to share the findings with national authorities and to seek ways to best adapt the lessons in each national context.

The UN General Assembly at its 67th session in December 2012 decided to convene the Third World Conference on Disaster Risk Reduction, in Japan, in early 2015 to review the implementation of the Hyogo Framework for Action and to adopt a post-2015 framework for disaster risk reduction (A/Res/67/209). The Third World Conference will be held from 14 to 18 March 2015 and is expected to result in a concise, focused, forward-looking and action-oriented outcome document. Study tours to the tsunami inundated areas will be organized to share with the international community, the live lessons from the gigantic tsunami and the on-going efforts to build back better.

7 Conclusions

Japan, throughout her history has long dealt with disasters, and even in recent two centuries when modern scientific observation was introduced, has accumulated experience of confronting with typhoons, earthquakes and tsunamis. Through these bitter experiences, Japan was prepared against strong M8 class earthquakes and tsunamis of 30 to 150 year return period. However the 11 March 2011 Great East Japan Earthquake was brought by a crustal movement greater than the Jogan Earthquake 1100 years back in history. It is truly regretful that the latest scientific investigation on tectonics of Japan Trench was not advanced to caution with enough scientific evidence, the probability of M9 class earthquake. On the other hand, structural and non-structural earthquake countermeasures based on the experiences of the 1995 Hanshin-Awaji (Kobe) Earthquake and the 2004 Niigata-Chuetsu Earthquake have proven to be effective in earthquake disaster risk reducton. New technologies based on the latest scientific knowledge such as the Earthquake Early Warning, the Shinkansen Early Earthquake Detection System and the micro-chip controlled gas meters have proven its great value. Also disaster awareness programs for students demonstrated how they can save lives.

The entire picture of the Great East Japan Earthquake & Tsunami is still being clarified. Detailed investigations on causes of casualties and various damages are underway. If Japan has the political will to pursue disaster risk reducton as a priority, the casualties will definitely decrease, even if there is to be another M9 earthquake & tsunami in the future. And by sharing these expertises with the international community, Japan would be able to contribute to the global issue of human security. The Third UN World Conference on Disaster Risk Reduction to be held in Sendai in March 2015 will be a good opportunity to share the lessons with the international community and contribute to the formulation of the post-2015 framework for disaster risk reduction.

References

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Citation

Nishikawa, S. (2015): Incorporating Science and Technology for Disaster Risk Reduction, – the Japanese Experience. In: Planet@Risk, 3(1): 95-106, Davos: Global Risk Forum GRF Davos.