Paper Submitted to IUPEA Conference, Louisville, USA 4-8 September, 2004
A Japan’s Challenge towards Anticipatory and Participatory Urban Disaster
Risk Management: Case Study of Tonankai Earthquake Disaster Initiative
Norio Okada* and Hirokazu Tatano*
*Professor of Integrated Disaster Risk Management, Disaster Prevention
Research Institute, Kyoto University, Gokasho, Uji, Kyoto, 611-0011 Japan
Seismologists alert that within the next 50 years a gigantic scale of periodic earthquake will
attack the Tokyo-Nagoya-Osaka Pacific Regions in Japan with a probability of more than 90 percent.
This is called “Tonankai Earthquake” and well known as its simultaneous linkage to “Tokai
Earthquake ” and “Nankai Earthquake.” Possible damages of this twin or triple earthquake could be
immense and thus effective risk mitigation and preparedness need to be achieved in anticipation of
such catastrophic risks.
This paper addresses an ongoing challenge in Japan under this earthquake risk, with a view to
introducing a new approach to disaster planning and management, i.e., anticipatory and participatory
disaster risk management. The core of this challenge is three-fold: i) anticipatory approach supported
by the methodology of urban diagnosis and adaptive management, ii) participatory process involving
multiple stakeholders, and (iii) integrated disaster risk management to be linked with urban planning
Based on author’s current field works, two illustrations are made and analyzed : one is an expert
initiative case at a metropolitan level and another an NPO initiative at a community level. Overall
assessment is made of both the effectiveness and limitations of the proposed approach. The paper
concludes by referring to the need for further research on knowledge management to better formalize
the implicit knowledge of socio-cultural contexts as well a the dynamic process of anticipatory and
participatory disaster risk management.
1. Introduction: Paradigm Shift Needed for Disaster Planning and Management
a) From segmental to more integrated
Japan is a country that suffers natural disasters frequently and thus has inevitably developed its
unique culture of living with natural disasters. However the process of modernization,
industrialization and urbanization in the post-war Japan has demanded more efficient and stressful
manners of land use, natural resources and the environment. This was a constant pressure and thus
became a seemingly self-evident mission for disaster prevention in Japan: to combat more
efficiently and effectively with nature and natural disasters, which meant automatically structural
(facility-oriented) approach to prevent natural disasters. Moreover this structural approach became
inevitably segmental (sectoral) and disintegrated into a narrow scope of facility-dependent practice.
For instance, river bodies were corseted by levees and dams and their surrounding regional and
geophysical spaces were cut off from the river bodies in the name of “the combat of flood control”.
Similar things tended to happen in city’s combat with earthquake disaster. Housing approach was
very commonly made, with little linkage to road and utility (lifeline) development, land use and
environmental management. Of course it should be fair to mention that “urban redevelopment and
rehabilitation policies” and their institutional instruments have been introduced to better coordinate
such “otherwise segregated practices.” The idea behind was to modernize disarrayed and unsafe
urban spaces by surgically reshaping the geo-spaces into higher quality ones. Difficulty was: it took
a long time to complete the project and in many cases an earthquake and/or fire disaster occurred
before the project was finished or even started. Consensus-building was a big barrier but economic
and financial ones were even harder, particularly in economically depressed time and areas.
Importantly another drawback to this type of large-scale surgical approach was the risk of damaging
or ruining existing neighborhood communities. Ironically this could have sometimes put the cart
(surgical rearrangement) before the horse (community life). That is, inversion of objectives and
Given such a situation, we need to get back to our objectives and seek for other alternative courses
of action, i.e., more physiological and diagnostic approach (of which surgery is a part.) Let us call
this approach “urban (community) diagnosis” approach.
b) Retroactive to more proactive, and Single-scenario to Multiple-scenario
The segmental approach that dominated the conventional practice of a whole set of structural
(facility-based) disaster planning activities was principally concerned with “proactive” measures to
“prevent” particular disasters. However this approach had the above-mentioned weakness, that is,
lack of integration.
On the other hand, Japan has developed and specialized a unique domain of law-endorsed “bosai
keikaku” or “disaster planning.” This law-based disaster planning intended to cope with all types of
frequent natural hazards (disaster-triggering events but not necessarily resulting in disasters) such as
typhoons, heavy rainfall in the rainy season, high tides, etc. In this sense this disaster planning is
committed to different hazards and thus rather holistic and integrated. Characteristically it is
distinguished from facility-based disaster planning. The former is basically concerned about
retroactive (i.e, response-relief, rescue, and recovery) practice, and the latter proactive. Notably the
planning of such retroactive measures requires some working scenarios. The conventional practice
of law-based disaster planning has commonly adopted a single-scenario in setting up the context of
contingency. Justification was that it mainly assumed coping with frequent natural hazards, rather
than less frequent ones.
c) Lessons from the 1995 Hanshin-Awaji Earthquake Disaster
A turning point of Japan’s disaster planning and management came when Kobe and its neighboring
metropolitan region (Hanshin Region) were struck by a near-field earthquake in 1995.
The region was not prepared at all for such a near-field earthquake and thus the damage was
immense. Lessons learned from this devastating disaster were as follows:
1. low-frequency, high-impact disaster (catastrophic disaster) requires a special approach
different from the conventional one (Japan has been rather familiar with.)
2. Coordinated approach to maximize the integrated capacity for the region to cope with
holistic aspects of such a catastrophic disaster
3. Failure-masked approach to fail-safe, risk management approach
Related to item 2., the importance of coordinating “daily mode” with “emergency mode” was
recognized. That is, coping capacity in the emergency mode will be even more greater and flexible if
repeatedly trained and exercised as continuous activities of daily mode. Related to item 3. risk
mitigation and preparedness particularly before the disaster event calls for more attention in disaster
Item 3 also meant that the mindset attitudes of disaster managers should be changed. They tended
to mask potential failures of disaster planning and management by presenting common people with
rather failure-free (safe and secured) images of disaster prevention. The distinction between
aspiration and actuality in disaster planning and management was not professionally clarified to the
public. This conventional attitude has to be changed, and more accountability and transparency need
to be guaranteed. It is also important to design and introduce its institutional scheme .
With such viewpoints in mind, Okada and Tatano proposed a conceptual model to broaden the
scope of disaster management. The point was to envision the region (land, city, and community) as a
vital (living) common space. Disaster management should treat regions to enhance their holistic
quality in safety and security. Notably regions are vital common temporal and spatial spheres of
different scales. Fig. 1 illustrates their five-storied pagoda system for this purpose. People’s life is on
top with a highest time scale in change, and natural environment is at the base with a lowest time
scale in change. Disaster prevention now needs to extend its approach based on this pagoda model.
Life in Community
Culture and Convention
Fig.1 City as a five-layer vital system (Pagoda Model)
d) Integrated disaster risk management to be incorporated into sustainable management-
with “vitae system” model as a basis
With above discussions overall assessed, Okada (2004) proposed another conceptual model
(see Fig.2) This model proposes to base both “sustainable management” and “disaster planning and
management” on the common ground. The uniqueness of this “conceptual construct” is in its
claim that both “sustainable management” and “disaster planning and management” should address
the fundamental question of “why sustainable?” and “why safe and secured?” The model makes the
point that it is because it has to treat living bodies that are endowed with coping capacity to maintain
both life at the end of death and life at the end of liveliness. The coping capacity facing the former
end is called “survivability” and the latter “vigorousness.” The horizontal latitude between both
ends is considered “vitality” on individual level. Importantly this vitality reveals itself tensed by both
ends, and thus both “survivability” and “ vigorousness” concur and coexist. Let us call this
dimension “horizontal axis.” Another dimension we should not forget is “societal aspects” of living
bodies. Therefore we conceive of the vertical axis that addresses the latitude of any living body
collaboratively coping with risks surrounding itself.
Thus we develop a view of a triangle-shaped coping capacity of the living body (vitae system).
The entire area in size of this triangle vitae system may well be interpreted as its dynamic coping
capacity. Let us call this “viability” of the vitae system.
This conceptual model helps us explain and analyze essential features of framing the scope of
disaster planning and management. For instance, the importance of coordinating “daily mode” with
“emergency mode” as pointed out above can be interpreted as the length of the latitude along the
horizontal axis of the vitae system. The longer the latitude becomes, the greater and flexible the
coping capacity of this living body becomes. Thus we may think of our performance criteria with
which to evaluate the quality of integrated disaster risk management.
Social Life Quality of Life
Survivability Coping Capacity Vitality
At Death Risk
Fig. 2 Conceptual Model of Vitae System for Sustainable Manegement
And Disaster Management
To summarize our above discussions Table 1 compares the conventional type of disaster
planning and management with a new one. One important point made in this table is still not
covered. That is the need to adopt anticipatory (precautionary) approach and this requires adaptive
management as a methodology. This point will be explored later.
Table 1 Conventional and 21 Century types of Disaster Planning (and Management) Compared
Conventional disaster plan 21st century integrated disaster planning and
emergency and crisis management risk mitigation + preparedness
countermeasure manual approach anticipatory/precautionary approach
predetermined planning adaptive management
sectoral countermeasure approach comprehensive policy-bundle approach
4. Research Challenge: Tonankai Research Project
1) Tonankai Earthquake
Tonankai and Nankai
Return Period：９０-１５０ years
In １９４４ Tonankai E. , and in１９４６ Nankai , each occurred along Ｃ，Ｂ
segments）spreading eastwards, and westwards, respectively.
Fig.3 Tonankai and Nakai Earthqauke Mechanism
Table 2 Occurrence Probability Predicｔ
<Source:Japan Earthquake Investigation Committee(2001)>
next 30 years 50% 40%
next 40 years 70-80% 60%
next 50 years 80-90% 80%
Tonankai Earthquake is potentially a twin or triple earthquake that could occur
practically simultaneously (from the same day scale to years delay scale.) The last case
of the Tonankai Earthquake Disaster happened in 1944 and its twin one, the Nankai
Earthquake Disaster occurred in 1946, two year later (see Fig. 3). The next Tonankai
is predicted to occur within the earlier half of this 21 st century with a probability of 80
to 90 percent (see Table 2). This twin or triple earthquake disaster is known to be
periodic with a frequency of 100 to 150 years. Every time it occurs, it is twin or triple
and the impact of each single earthquake is colossal, with a magnitude of more than
8.0 in Richter scale. If multiplied by simultaneous occurrences, the damage would be
The Government of Japan and research communities of natural hazard and disaster
prevention in Japan have already started special research projects such as “Daitoshi-
Daikibo Jishin Saigai Tokubetsu Project” known as “Dai-Dai-Toku Project” for short.
(The meaning is Pacific Megalopolis Catastrophic Earthquake Disaster Research
Initiative Project. We commonly call this “Tonankai Initiative Project” in English.)
2) Anticipatory and precautionary approach
What is innovative about this special research project in Japan is that it takes a challenge
towards what is predicted by seismologists to occur in a “near” future on “human lifespan
scale.” Notably the hazard mechanism of this earthquake is not totally known and precise
timing and place of its occurrence is not predictable, in a manner enough to prepare and
evacuate before its occurrence. However with our current best knowledge and technology, we
are committed to take appropriate countermeasures at this moment “tentatively”, assuming that
adaptive management will be employed to cope with any deviations possible in the courses of
future development (see Fig.4). This means that we are now exercising an innovative approach:
Let us anticipate with our best knowledge and technology and precaution against doing nothing
until something happens.
Fig. 4 Adaptive Management Cycle
Performance Indices in the
Collaborative Modeling Process
Claims Performance Based
Interest of Stakeholders
Fig. 5Collaborative Modeling in line with Adaptive Management
3) Multi-level Participatory Approach
To anticipate the imminent Tonankai Earthquake, we need to introduce Multi-level Participatory
Approach. The reason is : the impact of the earthquake would be immense and distribute across
regions and down to local communities. Thus how to cope with such a complex disaster, local
communities should be ready to help out each other and in the worst situation each resident would
have to secure one’s life immediately after the event. This kind of coping capacity need to be
fostered on community level in anticipation of the Tonankai Earthquake. On the other hand
administrators and experts engaged in inter-regional disaster management are expected to work
together and develop effective mitigation countermeasures and implement them in advance.
Therefore the scope of concerns and governable means are just different between inter-regional
(metropolitan) and neighborhood community levels. Consequently both require participatory
approach but types of management should be differentiated.
4) Ima-simulation and Collaborative Modeling
It is noted that anticipating imminent Tonankai Earthquake and take precautionary measures in
advance is a challenge to laymen’s perception and risk attitude because it forces us to raise our
common awareness against “unlikely event, ” to change our behavior and to take a risk-mitigation
action in advance. For this purpose we propose the best use of simulation techniques in order to
activate our imagination of how devastating the disaster would be to each individual and particular
communities. For instance, information technology can be best use of to create inexperienced events
This is not necessarily to reproduce or simply simulate but to create new possible events and their
development processes. Therefore we propose to call it “Ima-simulation” instead of simulation (see
Fig. 6 ).
In our ongoing case study in the Nagoya and Tonankai metropolitan region, there are two different
types of “Ima-simaulation” being “socially tested.” On the metropolitan level, “socio-economic
vulnerability assessment ima-simulator” has been developed as a prototype version and it is used,
tested and evolved by participants from administrators and disaster professionals on a voluntary
basis. This new style of modeling is referred to as “collaborative modeling.” We are finding this
approach an extremely effective and new fashion of participatory-supportive risk management (see
On the community level ima-simulation and collaborative modeling are intended to take a distinct
feature than that on the metropolitan level. For instance, in Nagoya City a workshop-based
participatory disaster management approach is being “socially tested”. Thanks to the initiative taken
by a local NGO who has built on disaster management expertise since 10 years ago. Here ima-
simulation takes the form of letting local residents participating in the series of workshops acquire
the skill of fixing their “risky furniture” rigidly and securely to the wall or floor. This is even
“implemented” by letting the participants practice it with the help of some experts attending. Here
“ collaborative modeling” means the socially tested and evolved process of participation for “small
but steady” implementation.
Characteristic of Risk Management
(Fail-Safe System) Local
(Multiple-Stakeholder Participatory System)
Fig. 6 Imasimulation-oriented Participatory Risk Management
The Tonankai Research Initiative Project is still an ongoing project. The approach challenged in this
research project is itself a part of adaptive management and a participatory approach. With further
evidences and facts collected and monitored through our anticipatory, precautionary research
development, we will monitor and adapt our research development process and our working
scenarios. Further research developments will be reported in a near future.
Hirokazu Tatano, Yasuaki Shoji and Norio Okada, Long-Term Effect of Disaster
Mitigation Investment upon Regional Economy, A Multi-Regional General
Equilibrium Approach Proceedings of Japan-US Workshop on Disaster Risk
Management for Urban Infrastructure Systems, Kyoto, Japan, May 15th,
Hirokazu Tatano, Yasuaki Shoji and Norio Okada, A Multi-Regional General
Equilibrium Analysis Taking Account of Disaster Risk, 2001 IEEE
International Conference, pp.1773-1778, 2001.
Yoshio Kajitani, Norio Okada, Hirokazu Tatano, Spartial-Temporal Analysis of
Human Community Viability by Niche Indices- A case study of Disaster
Affected Region, Proceedings of Third Joint Seminar on Urban Disaster
Management, pp.30-35, 2002.
Ye Yaoxian, Norio Okada, Achievements of Joint Research on Management of
Urban Disaster Risks for the Phase Ⅰof the EQTAP Project, Proceedings of
Third Joint Seminar On Urban Disaster Management, pp.78-82, 2002.
Okada, N., A New Trend in Disaster Management –Towards New Public Risk
Management and Urban Diagnosis, Invited Paper at Japan-China Policy-Maker
Seminar on Urban Disaster Management, Xiamen, China, 2003.
Hiroyuki Sakakabara, Yoshio Kajitani and Norio Okada: Road Network Robustness
for Avoiding Functional Isolation in Disasters, ASCE Journal of
Transportation Engineering, forthcoming, 2004.
Hirokazu Tatano, Kentaro Yamaguchi and Norio Okada: Risk Perception,
Location Choice, and Land-use Patterns under Disaster Risk: Long-term
Consequences of Information Provision in A Spatial Economy, Yasuhide
Okuyama, Stephanie Chang(eds) ‘Modeling Spatial Economic Impacts of
Disasters’, Springer-Verlag, pp163-180, 2004.