Disasters caused by local heavy rainfall have occurred frequently during the past decades in Japan. After World War II, the Tokyo metropolitan area experienced repeated flooding, including that caused by the bursting of the Tone River by Typhoon Kathleen in 1947. Corresponding to increasing urbanization, flood control measures were implemented locally in each basin. Simultaneous occurrence of multiple floods is a matter of concern and requires adequate countermeasures. In this study, the need for new measures involving the monitoring of retarding basins, regulated areas, and floodways after heavy rain , was investigated using satellite images, and the importance of a broad-scale simultaneous disaster response was highlighted.