FACTORS CONTROLLING THE PLUVIAL FLOODING IN THE DOWNTOWN AREA OF YANGON, MYANMAR WITH THE OLD STORM DRAINAGE SYSTEM

Abstract

 In recent years, cities are facing pluvial floods more frequently due to global climate change and rapid urbanization. This problem causes more severe damages in the cities with old aged drainage infrastructures. In these cases, the urban drainage systems cannot meet the original design requirements, which causes traffic jams and hygienic problems in the downtown areas. This study adopts InfoWorks Integrated Catchment Modeling (ICM) to evaluate the effects of design storms and channel sediment depths for the old storm drainage system in Yangon, Myanmar on the urban flood severities. The simulations with different design storms clarify that they have larger effect on flood discharges but smaller effect on flood durations, relatively. Whereas, those with the varied sediment depositions suggest that they could strongly influence both of the flood discharges and durations. The study could find that the maintenance work was essential for the reduction of such the urban flood severity.