Abstract
In this study, we focused on the effect of the riverbed aggradation to the scale of the flood inundation. Using the distributed runoff model, one dimensional riverbed variation calculation and 2 dimensional flood inundation mode, we performed a flooding analysis for a flash flood in an ungauged basin. Due to the limitation of the available dataset, firstly we performed a riverbed variation calculation using observed daily discharge and water level that were observed during April-Sept 2000. Secondly, we performed a runoff analysis using 3 hourly satellite rainfall data that was observed during April-May 2006. Finally, riverbed data and discharge data was considered to the flash flood inundation analysis. As a result, after the riverbed aggradation was considered, the flood area become 2 times larger that the case riverbed aggradation was not considered.
