Wide-area Evacuation Research Articles

Multiple relocation cases in disaster-related deaths after the Fukushima nuclear accident

IntroductionRelocation after a disaster often has negative health effects on vulnerable people, particularly older adults. However, little is known about the number of repeated evacuations and relocations after disasters among those experienced disaster-related deaths. This case series aimed to summarize the secondary problems and mortality risks in patients involved in relocation after disasters.MethodsWe analyzed and summarized the data on 520 disaster-related deaths in Minamisoma City, a municipality near the Fukushima Daiichi Nuclear Power Plant, focusing on the number of relocations. Herein, we describe the cases of three individuals over 80 years old, who died after eight or more relocations, which were certified as disaster-related deaths.ResultsWe discuss following three cases, which are (1) a female patient in her 90s who had a stroke and was completely disabled, (2) a female patient in her 80s whose cancer was detected later due to her failing to see her family doctor, and (3) a male patient in his 80s whose regular postoperative treatment was disrupted following cancer recurrence.DiscussionOur findings indicate that evacuation led to the worsening of chronic diseases and eventually to post-disaster death. Prolonged wide-area evacuation and repeated relocation likely interrupted the continuum of care and led to the failure of adequate care provision. To reduce the loss of human life, it is necessary to review the number of wide-area evacuations and relocations over the medium to long term after large-scale disasters, including nuclear disasters, which may occur in the future. Simultaneously, it is important to establish a medical system at the evacuation site so that disaster victims can continue to receive medical care even after evacuation or relocation.

Utilization and development of evacuation time estimates in wide-area evacuation planning for nuclear disasters in Japan

Utilization and development of evacuation time estimates in wide-area evacuation planning for nuclear disasters in Japan

Categorizing resident evacuation behaviors within a flood-protected area

ABSTRACT Flood management due to global warming is one of the most important issues to be considered worldwide. Communicating about flood risk between government and residents is important for enhancing awareness of residents’ evacuation. However, not enough risk information is provided to residents for evacuation from floods (e.g. where, when, and how to evacuate). Therefore, an evacuation analysis linked with a time series of inundation depths was conducted in Kawajima Town, which is surrounded by a ring levee in the watershed of the Arakawa River, Japan. According to the analysis of evacuation by walking, the evacuation should be started by the time an evacuation instruction is issued to avoid getting caught in flooding before reaching shelters. Although the analysis of evacuation by car did not consider road and bridge closures, it indicated that approximately 40% of the town’s residents would likely have difficulty evacuating to even the nearest bridge or road. The central and southern part of the town was also identified as an area where a wide-area evacuation, i.e. outside the town, would be difficult if road and bridge closures were considered. The risk map identifies high-risk areas and districts in the central, southern, and southwestern parts of the town. It also indicates the need for structures for emergent use, such as small mounds or towers for evacuation starting at the breaching time (BT) in these areas. Since there is no area where all residents can evacuate at the start of breaching time, it is necessary to start evacuation to shelters immediately after the evacuation instruction is issued. Because the number of municipalities with similar problems will increase in the future in Japan, the study of evacuation plans from flood inundation for residents in Kawajima Town is expected to serve as a model case for other municipalities to consider.

The Possibility of Wide Area Evacuation in the Event of Natural Disasters: A Survey in Amagasaki City, Hyogo Prefecture

In industrial clusters that are affected by earthquakes and tsunamis, advance countermeasures are necessary to ensure the continuity of business operations of companies. This article presents the results of a questionnaire survey of small- and medium-sized enterprises in Amagasaki City, Hyogo Prefecture, to determine the current status of disaster countermeasures, and a questionnaire survey of residents’ awareness of risks and their current countermeasures.

A Study on the Strategy for Responding to Large-Scale Complex Disasters

Purpose: A large-scale complex disaster refers to a disaster that develops on a huge scale outside the predictable range as natural disasters and social disasters occur serially or simultaneously. The local community must take into account the diversity of residents' situations and organize an evacuation cooperation system in advance in order to respond to such large-scale, complex disasters. The purpose of this paper is to present a direction for improving community response to disasters through a review of large-scale complex disasters.
 Method: This study examines the large-scale flood damage evacuation plan in the 5th district of Koto, Tokyo, Japan, which established an evacuation plan led by the local community after the Great East Japan Earthquake. Evacuation was divided into vertical evacuation, evacuating within the community, and wide area evacuation, evacuating outside the community.
 Results: The main features of these evacuation plans were that they encouraged local residents to make independent judgements, to implement the plans, and to proactively request and prepare for administrative support for the parts that were insufficient.
 Conclusion: First of all, for efficient evacuation from large-scale-complex disasters, various stakeholders need to be recognized and systematically organize, and cooperation with relevant and upper-level administrative agencies is needed to solve problems that are beyond the capacity of local governments. It is also necessary for residents to recognize their own role in disaster response along with the proper implementation of disaster prevention administration, and for the administration to support factors that residents cannot do as much as possible, as the basic structure of the crisis.

Cross-border evacuation and intermunicipal cooperation during large-scale flood disasters

The frequency of flood disasters has increased in recent years, leading to significant damage worldwide. Developing global risk-reduction strategies, such as cross-border evacuation, is necessary. The effective spatial range for intermunicipal cooperation is an important factor in implementing cross-border evacuation. Thus, this study investigates the effects of cross-border evacuation in large-scale floods by comparing inner and cross-border evacuation scenarios using GIS network analysis. The spatial range of inter-municipal cooperation is clarified based on a case study from Japan. The major findings are as follows: First, cross-border evacuation has the potential to reduce the evacuation time in many cities. Specifically, out-of-city shelters constitute the nearest shelter option for 24% of evacuees. Cross-border evacuation may reduce evacuation time by up to 14%. Second, cross-border evacuation is unsuitable for certain cities because of congestion at the boundaries. Third, community detection that finds the subnetwork with strong dependency between cities can suggest the effective spatial range for inter-municipal cooperation. Fourth, the shelters and route of cross-border evacuation considerably differ with inner evacuation. The evacuation plan requires specific guidance. This study helps identify the areas that would benefit the most from implementing cross-border evacuation and contributes to developing a wide-area evacuation plan in cooperation with neighboring cities.

Research conducted in the Dr. Takuya Oki Laboratory

Associate Professor Takuya Oki, Tokyo Institute of Technology, Japan, is using big data and AI technology to address issues associated with architectural planning and urban planning research. Through his research he hopes to provide basic data that can be used in architectural and urban design and in the design and development of urban spaces. He also predicts his research can be used in the analysis of problems within existing spaces and the provision of improvements. Oki is also working to develop a real-time evacuee distribution estimation technology in collaboration with the University of Tokyo's Assistant Professor Yoshiki Ogawa and Associate Professor Masaaki Imaizumi, and the Shibaura Institute of Technology's Associate Professor Yuki Oyama. The goal of this work is to help solve the problems of developing a wide-area evacuation simulation model that was originally proposed in Oki's doctoral thesis. To do this, the researchers are using an AI technology called a graph neural network (GNN) model to learn the movement tendency of evacuees from a limited number of simulation results. The team is also using data assimilation to reduce error. Oki is also working on research for the Consortium for Socio-Functional Continuity Technology (SOFTech) surrounding 'ensuring peace of mind', which involves analysing the gazing tendencies of TV viewers and pedestrians when disaster prevention-related information is presented.

Conflicting Characteristics between Wide-area Evacuation and Intra-area Evacuation for Large-scale Floods

Conflicting Characteristics between Wide-area Evacuation and Intra-area Evacuation for Large-scale Floods

Analysis of Evacuation Time for Vulnerable Individuals During Inundation of Lowland Areas

There is an increasing demand for establishing pre-emptive measures for disaster management. However, there is a lack of support systems available for vulnerable individuals living in disaster-prone regions in Korea. This study constructs a multi-agent simulation model to analyze the evacuation time for Dongnae district and Yeonje district in Busan, Korea. In disaster-prone regions, vulnerable people experience difficulties, such as, obtaining updated information about the disaster situation, and this reduces their evacuation speed. Additionally, there is a possibility that the evacuation speed, while evacuating vulnerable people, may decrease due to environmental and geographic factors, including the slope and elevation of the areas. Therefore, this section of the society requires special attention and policies that are different from those made for people who may not face such calamities and are physically abled. An analysis based on factors such as road slopes and delays in evacuation due to flooding, was conducted to formulate realistic evacuation plans for people who are vulnerable. The location of shelters in the case of flooding in Dongnae and Yeonje district, have been better identified. Furthermore, it was confirmed that the evacuation time could be reduced if wide-area evacuation is implemented. This study provides a base for developing suitable shelters and evacuation plans for disaster-prone regions.

Selecting the Best Links for Lane-reversal in Wide-area Evacuation Based on the Critical Edge Model of Dynamic Maximum Flow Increase

Based on the theory of dynamic flow, we study the optimization problem of dynamic reverse lane, that is, the selection of the road section and the optimization of the time period of lane reverse operation. We abstract an evacuation road network as a directed network with variable capacity, and define the critical dynamical edge for increasing the dynamical maximum flow value of such network. We can get alternative links and corresponding time period for lane-reversal operation by searching critical dynamical edges for increasing the dynamical maximum flow value. We present a modified algorithm to find such critical dynamical edges on the basis of the maximal capacity path algorithm for the static maximum flow problem. We also give a numerical example and test the effects through traffic simulation. The results show that evacuation time can be effectively decreased through taking dynamical reversal lane scheme in regional evacuation.

Building Up a Common Recognition of City Development in the Southern Part of Kofu Basin under the Initiative of Knowledge Brokers with the Cooperation of Experts

Extreme weather caused by global warming has caused an increase in the number and intensity of heavy rain disasters. Almost half the area of the Kofu Basin, Yamanashi Prefecture, Japan, is expected to be flooded by the largest expected rainfall in the basin. Approximately 310,000 people live in the inundation area, and the formulation of a wide-area evacuation plan in the event of a flood is an urgent issue. In the southern part of this area, where the estimated inundation depth is 5–10 m, a new station of the Linear Chuo Shinkansen Line, which will start operation in 2027, is planned, and urban development centered on the station is expected. In order to build a sustainable city that is resilient to floods in such a flood hazard area, the author established a study group on urban development consisting of knowledge brokers—professors at University of Yamanashi—and experts with the participation of local government observers. The group has proposed a future image of sustainable Kofu Basin under the initiative of knowledge brokers with the cooperation of experts. The group attempted to put into practice the concept of sustainable cities presented by the author. As a result, by the unusual town development activities of the study group, perspective drawings that provide the participants a common recognition of the city development were successfully created.

Facilitating Community Risk Communication for Wide-Area Evacuation during Large-Scale Floods.

Large-scale floods have been occurring more frequently in Japan as a result of current global weather anomalies, yet evacuation procedures face several issues. These include low evacuation rates of citizens, wide-area evacuation by car, and residents who cannot evacuate on their own. For example, in the Kofu Basin, Yamanashi Prefecture, due to the size of the potential inundation area and a population that exceeds 300,000 people spread across 10 municipalities, a large number of residents would have to evacuate across municipal boundaries by car. The author proposed and applied a risk communication method to the Riverside District, Chuo City (with about 1400 households and a population of about 4000), assisting in developing a community disaster management plan for wide-area evacuation without a single victim in case of floods, which has been in place for three years. The next step was risk communication to key stakeholders, such as national, prefectural, and municipal governments. Finally, a public symposium on large-scale evacuation in the Kofu Basin was held. During the panel discussion with representatives of the Kofu River and National Road Office, prefectural government of Yamanashi, the municipality, community residents, and the author as panelists, the role of each stakeholder in area-wide evacuation was clarified and confirmed.

Quick Estimation Method of Property Damage and Human Casualty in the Event of a Large Earthquake

Techniques for quickly and easily estimating wide-area damage are required to support various activities for reducing damage in the event of a large earthquake. In this paper, using a wide-area evacuation simulator, we estimate property damage and human casualties in 32 densely built-up wooden residential areas in Tokyo, assuming a large earthquake. Furthermore, the relationships among local urban environment, property damage, and human casualties are analyzed using multiple regression analysis.

Wide-Area Evacuation Simulation Incorporating Rescue and Firefighting by Local Residents

This article describes the development of a comprehensive simulation model that integrates property damages (building-collapse, fire-spreading, and street-blockage) and various activities (rescue activity, firefighting activity, and wide-area evacuation activity) by local residents in the event of a large earthquake. Using this model, we analyze the effect and risk of rescue and firefighting activities carried out by local residents under the assumption that a large earthquake directly hits the Tokyo area. Furthermore, we attempt to find new knowledge on the situations where there are many fatal casualties caused by people failing to evacuate, being trapped on streets, and so on.

Proposed evacuation tunnels for wide-area disaster

The present paper proposes a safe evacuation method using underground evacuation tunnels for urban area evacuation owing to a wide-area fire disaster that may occur in the aftermath of a major earthquake. To survey the effectiveness of the evacuation tunnels, evacuation completion time was estimated using wide-area evacuation simulations. It was discovered that evacuation completion time for underground tunnels was one hour faster than that of evacuation above ground (even with the widening of the surface roads) if tunnel usage was appropriately controlled so that vulnerable people (i.e., elderly people and children) used it while others evacuated above ground. Moreover, an estimation of the construction cost of evacuation tunnels in a metropolitan area indicated that one could be built at the same, or even lower, cost than that of the road widening above ground.

Modeling Human Behavior of Local Residents in the Aftermath of a Large Earthquake – Wide-Area Evacuation, Rescue and Firefighting in Densely Built-Up Wooden Residential Areas

It is very important in disaster prevention planning to estimate the level of human damage after large earthquakes under various scenarios that takes into account the day of week, the time of the disaster, weather conditions, earthquake intensity, etc. There have been many previous studies based on the spatial characteristics of urban areas about evaluating protection against fires, evacuation risks, and the safety of evacuation routes to designated areas. However, no study so far has integrated models of property damage (building collapse, fire spread, and street blockage) and human behavior (rescue activities, firefighting activities, and wide-area evacuation behavior), and carries out simulations in order to analyze human damage in detail. In this paper, we present a survey of previous studies of the methods of evaluating urban-area characteristics, rescue and firefighting activities, and wide-area evacuation, all of which have been discussed as separate issues. We summarize the findings within the respective fields, their methods of evaluation and modeling, and identify their issues. Based on this survey, we point out that the construction of an integrated simulation model requires six important activities. They are to: 1) carry out evaluations on a microscopic scale at the block or street level; 2) use an evaluation index that allows a direct grasp of the expected level of human damage; 3) take into consideration many detailed and concrete disaster scenarios; 4) take into consideration the interactions among rescue participants, firefighting participants and wide-area evacuees, along with the effects of property damage; 5) incorporate the concept of time; and 6) set up comparative scenarios that allow the quantitative evaluation of the effects of various measures or policies. Therefore, it is necessary to construct a model based on the concept of multi-agent simulation (MAS).

住民による救助活動を組み込んだ大地震時における木密地域の広域避難シミュレーション分析

In order to reduce human casualties, rescue activities by local residents play an important role in the chaotic times immediately after an earthquake occurs because it is difficult to expect the sufficient and quick support by public rescue teams such as firefighters, police officers and the Self-Defense Forces. Therefore, it is necessary to quantitatively understand both the effects and risk of these activities based on the numerical analyses, and concretely discuss how to perform rescue activities by local residents as part of disaster mitigation planning. In this paper, we incorporate the following aspects into the wide-area evacuation simulation model which we have previously developed: (1) people trapped in a building and on a street; (2) rescue activities by local residents; (3) the behavior of people who get over the rubble of collapsed buildings; (4) the difference of the attribute of evacuees. Using this simulation model, first, we demonstrate the effectiveness of rescue activities by local residents in densely built-up wooden residential areas in the aftermath of a large earthquake. Even considering the influence of property damages (such as building-collapse, fire-spreading and street-blockage) and the necessity of wide-area evacuation after an earthquake occurs, it might be possible to reduce the number of casualties by 13.7% in average in case that local residents themselves perform rescue operations. Also, the number of people who die after the participation in rescue activities is less than half of the people saved from the collapsed buildings in average. Next, we attempt to describe the relationships among elapsed time from an earthquake occurrence, property damages, human casualties and people engaged in rescue activities. Although fires still continue to spread after 12 hours pass since an earthquake occurs, the peak of the number of people who are saved from collapsed buildings or engage in rescue activities is about an hour passes since an earthquake occurrence time. Also, it becomes extremely difficult for local residents themselves to find people trapped in a building after five or six hours pass since an earthquake occurs. The effective hours to perform rescue activities are different according to the earthquake occurrence time, the damage state of each building, the rescue ability of local residents, the spatial characteristics, etc. However, the methods proposed in this paper enable us to quantitatively understand the process of rescue activities by local residents in a certain scenario of a large earthquake. Furthermore, we analyze characteristics of places where many people might be dead or trapped on a street. Focusing on the spatial distribution of casualties and people trapped on a street, we can find the following tendencies: (1) the possibilities that casualties occur are higher and the number of those people is more in more densely built-up wooden residential areas; (2) the possibilities that casualties occur are much lower, but the damage scale is more devastating in the areas where the temporal refuges and large-scale housing complexes are located; (3) the possibilities that casualties occur are lower in areas facing on multiple sufficiently wide streets than other areas; (4) rescue activities by local residents result in a bit higher possibilities that casualties occur due to the delay of evacuation, but can contribute to less number of casualties in each area.

A Method for Evaluation of Wide-area Evacuation Difficulty in Case of a Major Earthquake

In densely built-up wooden residential areas, buildings and streets must be improved so as to safeguard against high risks, which may occur during a major earthquake. In this paper, we evaluate an improvement project in terms of the difficulty of wide-area evacuation by using a multi-agent simulation model. Results show that despite an overall decrease in the average number of people who have difficulty in evacuating, some buildings along narrow and long streets still have high risk that residents cannot evacuate to any evacuation areas.

自律群衆モデルに基づく広域避難シミュレーションからアプローチした滋賀県大津市における地域防災計画の検討

Our regional cities are always scared to big fire accident or earthquake every day. But the number of capacity of shelter does not increase, because budget shortfall of local governments might not take them in action. In contrast, Wide-area evacuation simulation can easily figure out the image to antagonize the regional urban disaster. And more, it can calculate the possibility of blocking escape route when the city is broken, and make safe evacuation plans before disaster occurs.

大地震時の市街地大火を想定した高齢者福祉施設における広域避難について

Senior users of elder care facilities are assumed not to evacuate to outside shelters, since the facilities are generally considered as evacuation centers. In case of a devastating earthquake, however, they might have to evacuate to outside shelters, since big fires are presumed to break out at the same time in different places. In this paper, we construct a simulation model, which describes evacuation behavior of senior users as well as urban fires following a major earthquake. We take into account that senior users with difficulties in walking need special support in evacuation process, and that the assistance of people around the facilities can reduce the human casualties. Using the proposed model, we quantitatively evaluate wide-area evacuation behavior of senior users, and demonstrate some significant factors affecting the availability of evacuation.