3. Analysis of Flood Character in the Mekong River Basin

Mekong River Basin (MRB) has suffered huge injuries and property losses from frequent floods, which would very likely witness an increase of flood magnitude and frequency under climate change. In this chapter, we set up a distributed hydrological model (THREW) to provide fundamental analysis of the flood characteristics in the MRB, the simulation period is 1991–2016, the spatial coverage is the whole basin except the delta region due to lack of reliable topographic data. Two main types of flood in the MRB which are riverine flood and flash flood are discussed. Flood peak frequency at mainstream stations along Mekong are achieved by Pearson-III Frequency Curve Fitting. The annual flood volume and duration at mainstream stations along Mekong River are calculated and analyzed. Taking the flood volume of damaging floods at Stung Treng station (at lower reach of Mekong mainstream) as subject, the THREW model is used to analyze flood’s travel time and regional composition, which would benefit flood prevention and water resources management from a whole-basin view.