Flood-Modeling and Risk Map Simulation for Mae Suai Dam-Break, Northern Thailand

Abstract

Dam-break floods are a serious disaster. This study aims to simulate and model the Mae Suai dam-break flood using shallow water equations (SWE) with an adaptive tree grid finite volume method, and determine the relationship between the initial water levels in the dam and the simulation results set regarding arrival times and maximum water depths using a polynomial model. We used elevation data obtained from the Shuttle Radar Topography Mission. The method was evaluated using the Xe-Pian dam-break flood simulation. The numerical results of water propagation was in agreement with the satellite image. The SWE and numerical algorithm was then used for the Mae Suai dam-break flood simulation. The numerical solution sets were approximated by a polynomial function of appropriate degree for flood arrival times and maximum water depth. Comparisons showed that the polynomial model results were similar to the SWE results; however, the proposed method was more efficient and can obtain a flood risk map without the need to fully solve the SWE. The method can also be applied for dam-break flood simulations and models in other regions using information from the dam.