The Applicability of Real Time Flood Forecasting Model: A Case Study in Thailand

Abstract

Summary : Severe flood damages in the southern region of Thailand caused by torrential rains or typhoons were found every year. Rainfall and water level were observed from a few monitoring stations in the region on daily basis. A real time flood forecasting model was formulated and applied to this region for flood disaster prevention. The model composed of two major components, the rainfall-runoff model and the hydrodynamic model. The rainfall-runoff model, a storage function model, was used to calculate the direct runoff due to rainfall. The hydrodynamic model, a vertically integrated model for mass and momentum conservation, was used to simulate flow in the river network. The model was able to predict water level and discharge at any location in the basin.Comparison between observed and simulated water levels and discharges from the numerical schemes indicated the applicability of the proposed model with satisfactory results, although time interval of observed data was longer than flood discharge arriving time. However, higher accuracy of the forecasting required more frequency of the observed . rainfall and water level data both in time and space. Telemetering system was also recommended for the implementation of efficient flood forecasting system.