Each local government has developed its emergency action plan by law for achieving safety and security of its citizens in case of big earthquakes to happen in its densely populated regions. A prediction of temporal change of the number of pedestrian evacuees described in the emergency action plan for the Nagoya Station area was evaluated quantitatively by our simulations. It has been found that the prediction has a great deal of safety margins by analyzing the crowd densities and speeds of pedestrian evacuees. If the predicted temporal change rate can be realized, there will be a very low possibility of traffic problems and accidents by crowds to happen in evacuation routes. In case of the temporal change rate being increased by 4 times of the predicted one, it has been found that the congestion level grows fast in a short period of time in a crossing area of pedestrian evacuees having different goals and no pedestrian traffics cannot be allowed in the crossing area.

 Based on a questionnaire survey on evacuation behavior of residents during flooding disaster threat in the upper Chikuma River basin (Saku City and Sakuho Town) affected by 2019 Typhoon Hagibis (Japanese name: No. 19), we have found: (1) that the evacuation rate among 50s was lower than the other generations; (2) many more 80s or older evacuated than youngers, and among 80s and older small number families showed higher evaluation rate. From Chi-squared tests and interviews, we have concluded that the awareness of evacuation information and the early warning are significant factors to lure evacuation during disaster threat, but daily practice of disaster preparedness. For the elderly these are more significant. We surmise that close communications in emergency in a community drived evacuation of the elderly.

 Safety inspections of concrete block walls in two districts on the south coast of Tokushima Prefecture were conducted with the aim of improving the safety of tsunami evacuation routes through collaboration between the government, residents, educational institutions, experts, non-profit organizations, etc. The results showed that by conducting an awareness survey and enlightenment activities for owners of concrete block walls in addition to the inspection survey of concrete block walls, we could grasp the issues necessary for the removal and repair and removal and repair of two block walls. In addition to creating a tsunami evacuation map that considers the collapse of concrete block walls, it was possible to clarify individual issues and the direction of countermeasures by examining case management for the removal and repair of concrete block walls.

 Preparation Guidelines for Reconstruction Town Planning came into effect in 2018. Some municipalities are working to relocate public facilities to higher ground in preparation for the Nankai Trough earthquake. The purpose of this study is to understand the current status and issues of pre-earthquake reconstruction efforts, including the relocation of public facilities to higher ground, as of March 2022, four years after the implementation of the Guidelines. A questionnaire survey was conducted with 139 municipalities that have been designated as special areas for tsunami evacuation measures in the event of the Nankai Trough earthquake. The survey asked about issues related to pre-earthquake recovery preparations, the status of public facility relocation, and the availability of subsidy programs for relocation promotion projects. In addition, interviews were conducted with municipalities that have already relocated public facilities to higher ground. The results were compared and characterized by the level of disaster risk, population size, financial size, and other factors. By learning the characteristics of municipalities that have made progress in pre-event reconstruction, it is expected that other municipalities will be able to find clues to solving their problems more easily.

 For large-scale disasters, the introduction of management by objective disaster response in ICS (Incident Command System) is progressing, centering on the operation of the disaster response headquarters. One is "creating a regular response plan", and the other is "setting goals and regularly checking and improving operations". However, although there are various case reports on "delegation of authority," which is another important pillar, discussions on the actual situation are insufficient. In this paper, we will clarify the actual situation and issues of delegation of authority at the disaster site from surveys of the prefectural government's branch offices for disaster cases in Wakayama Prefecture. In addition, it is presented that discussions such as "inter-organizational relationship theory" and "organizational behavior theory" are necessary.

 In July 2008, residents from Yoshida Town, Uwajima City, Ehime Prefecture, suffered tremendous damage from a torrential rain disaster. Positive evaluation of one’s life, a sense of happiness about life and the reduction of feeling isolated are important considerations to assist victims to rebuild their lives after experiencing a natural disaster. This study investigated the level of isolation risk and life satisfaction (through subjective well-being) of 350 households that were affected by the disaster in Yoshida Town. In addition, the study examined the determinants of life satisfaction. The results showed that life satisfaction of disaster victims was strongly related to their perception of social support and support from private organizations. In addition, significant differences were found in the determinants of isolation risk and life satisfaction between those who relocated and those who did not relocate after the disaster. Findings suggest that relocated persons feel more isolated. This highlights the importance of taking care of relocated persons so that they do not feel isolated in their new environment.

 In recent years, there has been a growing shortage of public transportation drivers. In addition, the increase in working hours associated with the shortage of drivers has encouraged drivers to retire. The result is a vicious cycle that leads to further driver shortages.

 Therefore, this study examined as a proposal a region facing increasing driver work hours and decreasing public transportation.

 For the study, multiple scenarios were created that would allow for both a reduction in bus driver work hours and the level of public transportation service, and scenario analysis and multiple regression analysis were conducted.

 The results of this study showed that a combination of increasing the number of bus drivers and withdrawing from some bus routes was more effective in reducing the workload of bus drivers than increasing the number of bus drivers engaged in route bus operations only.

 Permanent form method was used for concrete casting in the construction of a retaining wall for slope-failure control works. This method is to be effective in shortening the construction period, improving workability, and reducing construction costs because it does not require scaffolding or removal of the formwork, such as is the case with standard formwork. Further more, this method provides safety during the construction, because it reduces the number of work steps on the back side of the retaining wall, where there is a higher risk of slope failure. This paper examines the safety and economics of this method when applied to the construction of retaining walls, and confirms its effectiveness based on case studies of actual construction.

 In Japan, heavy rainfall disasters have been more frequent in recent years due to the effects of global climate change, and urban areas are frequently flooded. Flood waters contain generally water, sediment and debris. However, if there are facilities such as factories utilizing chemical materials in the flooded area, there is concern about their spillage. If these spillages occur, they will have a long-term negative impact on the flooded area. Also, farmers possess agricultural chemicals, which could be spilled if their farmland is flooded. Furthermore, households also possess chemicals such as detergents and bleaches, which could also be spilled. The study of countermeasures against the spillage of hazardous materials due to flooding is useful for the rehabilitation and reconstruction of flooded areas and for disaster mitigation measures.

 In this study, firstly, we reviewed past cases of hazardous materials spillage associated with heavy rainfall disasters focusing on USA and Japan. Next, the risk of hazardous materials spills in the event of flooding in Japan was investigated by classifying them into factories, farmhouses and households. Furthermore, the diffusion of hazardous materials was estimated using analytical solutions of the twodimensional diffusion equation without convection. Based on the above studies, countermeasures against the spillage of hazardous materials due to flooding are discussed and a few suggestions have been made.

 In July 2020, the enforcement regulations of the laws regulating real estate companies were partially amended, making prior explanation using flood hazard maps mandatory for transactions of residential land and buildings. However, the flood hazard maps currently prepared are based on maximum damage assumptions to encourage evacuation. Therefore, there are various problems when they are used to select residential areas.

 Therefore, in order to ascertain an actual situation, a questionnaire and interviews were conducted with consumers and real estate companies in Tokushima Prefecture. As a result, the following three problems were identified. First, current explanations using flood hazard maps may mislead consumers about flood risks. Second, consumers can evaluate convenience items but not safety itemas, and in addition they cannot accurately assume damage conditions and evacuation routes. Third, consumers' assessment of safety is affected not only by depth of inundation, but also by cost of the residential area.

 To solve the above issues, following three points were examined to realize a society in which everyone can choose residential areas based on an appropriate understanding of disaster risk: first, a mechanism to promote understanding of multi-hazard risk; second, the relationship between inundation depth and building damage and recovery costs; and third, the need to provide information on evacuation routes. Based on this study, the committee indicated how new flood hazard maps and other information should be utilized.

 In late years city planning and the need of the cooperation with disaster prevention measures are advocated because the inundation damage example of the Residence Guidance Area appointed in Local Normalization Plan occurs. And the government will perform urban development in consideration of a flood because Basinwide Comprehensive Flood Disaster Prevention Law was passed in 2021. Because the range of the Flood Inundation Assumption Area in the Urban Promotion Area is wide, in a past study, the citis that the reduction of the risk has difficult is clarified. This study conducted to ensure the security of such a city. As a result of this inspection, it clarified a problem to utilize a housing development outside the Urban Promotion Area, and to aim at the housing relocation of the inhabitants in the Flood Inundation Assumption Area.

 Typhoon No. 19, which occurred on October 6 in 2019, caused 14 overflows and flood overflows and one levee breach on the Chikuma River in the Shinano River. Although there have been reports of damage surveys of bridges over the Chikuma River, such as Chikuma River Bridge on Bessho Line, Tanaka Bridge, and Unnojuku Bridge, damage surveys focusing on the Chikuma River basin, including its branch rivers, have not been conducted. Therefore, in this study, we conducted a wide-area damage survey of bridges in the Chikuma River basin and organized the damage situation on a map in order to clarify the characteristics of bridge damages. In addition, damage factors of bridges were discussed from the structural (bridging year, total span, width, structural type) and the geographical (river bed gradient, river width, and degree of bends) perspectives. As a result, damage to 6 bridges in the Chikuma River and 14 bridges in the branch rivers were identified. Most of the bridge damage was influenced by bank damage, but 6 cases of bridge damage were found in the branch rivers, 3 of which were wooden bridges.

 In the field of meteorological forecasting, the development of ensemble forecasting has been promoted in recent years, and its use has been expanding. The authors propose "disaster potential," which is the possibility of weather disasters found in the forecast results, should be viewed not only as a future in the present, but also as a future that has passed in the past. In this study, as a basic investigation of disaster potential, based on various studies currently underway, the authors analyzed eight pieces of information indicating potential disaster risks to determine what kind of information can be formed and what characteristics these pieces of information have, and also surveyed their impressions of such information through a web questionnaire. The results showed that each piece of information has its own characteristics, and that these characteristics affect people's awareness of the diversity and potentiality of disaster risks.

 In the typhoon Hagibis in 2019, the embankment broke near 58km on the left bank of the Chikuma River, and one elementary school and two junior high schools in Nagano City were damaged by flooding on the floor. In order to collect the response cases necessary for creating an education continuation plan for inundation disasters, we conducted an interview survey with the Nagano City Board of Education and conducted inundation surveys around the schools. The two junior high schools reopened 18 days and 24 days after using the upper floors, and the elementary school that was flooded about 2 m reopened after 23 days using a nearby elementary school. As a result of efforts such as safety measures for school routes using buses and taxis, supply of school supplies, and cleaning and disinfection of schools, the school was reopened and education continued in a short period of time.

 The Sashiki River was flooded by the flood disaster caused by the heavy rain in July 2020, and more than 1, 500 houses were flooded in Ashikita Town. Due to this flood, schools and nursery schools in Ashikita Town were closed due to flooding of 0.1 to 1.6 m above the floor. From July 2020 to March 2021, a total of three inundation trace surveys and RTK-GNSS surveys were conducted, and inundation depth and elevation surveys were conducted at a total of 43 points. In December 2021, we visited the Board of Education and the nursery school and interviewed them about business continuity methods and issues. A two-dimensional flood inundation analysis was carried out for both the Sashiki and Yunoura river basins, and the inundation process was analyzed. Based on these results, we considered inundation measures for schools and nursery schools located in inundated areas and proactive measures for business continuity.