Flood risk management an illustrative approach

Abstract

Purpose In Kumamoto, Japan flood risk information is made available on several websites. In the event of heavy rainfall, local citizens need to access these websites and make household-level decisions. It is difficult for citizens to monitor all these sites, analyze and make effective decisions. Evacuation orders are issued by the local government who then filters the information to the relevant multiple stakeholders and local citizens. This takes time and reduces the response lead time of citizens especially in fast-onset floods. There was a therefore a need for illustrative integrated approaches, integrating these data sets. Design/methodology/approach Using precipitation, river water and tide level data, user-friendly real-time graphs were set up for the Shirakawa River, Kumamoto, Japan. Flood data were collected and used to create numerical simulations, and electronic community-based hazard maps were created. Findings The data gathered from the July 2012 flood event were used as a demonstrator, illustrating a flood event, as well as how to utilize the information provided on user-friendly real-time graphs’ website, to determine the location, future time and possibility of flooding. Additionally, an electronically generated flood hazard map-making process was developed for distribution across Japan. Research limitations/implications These illustrative approaches are relatively new and have only been tested and evaluated in communities across Kumamoto, Japan. As such, it is too early to determine robustness and generalized applications worldwide, especially in data-scarce countries and communities. Improvements and maintenance are ongoing. Practical implications These illustrative approaches can be adopted and utilized in cities and communities around the globe, thereby helping in overall disaster risk-reduction initiatives and better flood risk management strategies. Originality/value These illustrative approaches are new to Kumamoto City and Japan. These provide citizens with user-friendly real-time graphs that can be accessed anytime and used in flood hazard preparations, warnings, response or recovery.