Community-based risk management is increasingly recognized as a useful procedure for the mitigation of local-scale flooding. The purpose of this study is to develop supporting tools for flood risk management which match the demands of the local residents of a community in the town of Kosen in Kumamoto prefecture, Japan. The result of three years of community-based flood risk communication activities, including workshop discussions and evacuation drills, indicated the need for 1) sharing flood hazard zone information within the community, 2) tools for the realtime monitoring and alerting of local weather and hydraulic conditions, and 3) schemes for the confirmation of the safety of residents who require the support of others during evacuation. A real-time data acquisition and analysis system was developed which could embed the residents’ requested applications.