Author(s): Gwangseob Kim; Sunghwan Lee; Jin Moon

Linked Author(s):

Keywords: Bi-modal; Impacts of temporal variability of storms; Rainfall time distribution; Urban flood

Abstract: This study aimed to calculate and analyze the impacts of different bi-modal temporal distribution characteristics of heavy rainfall on urban floods. The manhole overflow quantity in the target urban basin was computed using the EPA-SWMM model and the inundation behavior was estimated using the two-dimensional flood model (FLO-2D). The bi-modal extreme rainfall events were produced using a rainfall time distribution model using the truncated Laplace function for different storm durations and return periods such as such as 1 to 3-hours and 20-year, 50-year, 80-year, 100-year respectively. The inundation model was validated using the inundation trace map of a urban basin in the Chunan city. The total overflow amount for same quantity and different time distribution rainfall events showed considerable differences. Furthermore, the inundation behaviors also were related to the temporal characteristics of storms such as the temporal location of storm peak and quantitative ratio of bi-modal distribution etc. Results demonstrated that the consideration of temporal distribution characteristics of extreme rainfall events is essential to understand the accurate inundation behavior in urban drainage basins.

DOI: https://doi.org/10.3850/iahr-hic2483430201-436

Year: 2024