Flash Flood Susceptibility Assessment Based on Morphometric Aspects and Hydrological Approaches in the Pai River Basin, Mae Hong Son, Thailand

Flash floods are water-related disasters that cause damage to properties, buildings, and infrastructures in the flow path. often occur within a short period of time following intense rainfall high, mountainous area northern Thailand. Therefore, purpose this study is generate flash flood susceptibility map using watershed morphometric parameters hydrological approaches. In study, Pai River basin, located Mae Hong Son Thailand, divided into 86 subwatersheds, 23 extracted from digital elevation model (DEM). addition, soil conservation service curve number (SCS-CN) used estimate precipitation excess, Snyder’s synthetic unit hydrograph method peak concentration. With respect dataset, we combined CHIRPS data (as satellite gridded data) with measured for runoff analysis. According analysis results, 25 out subwatersheds classified as highly susceptible areas floods. The similarities representing watersheds flood-susceptible indicate categorization included high relief, relief ratios, ruggedness stream frequencies, texture annual runoff, discharge, low elongation lemniscates ratios.