Risk assessment of flood based on dynamic simulation in downstream of reservoirs in coastal area of southeast China

Abstract

The coastal areas of southeast china are characterized by small watersheds with reservoirs in the upstream and high density of population in the downstream, and these watersheds generally have weak ability of storage and short flow concentration time. At the same time, with the rapid development of urbanization, the risk of flood disaster is increasing. So it is urgent to make a research on the risk assessment of flood in downstream of reservoirs with different frequencies of precipitation to provide technology support for decisions on flood prevention and alleviation. Therefore, a flood dynamic simulation model based on remote sensing, GIS, hydrologic and hydraulic model is employed in the hazard risk assessment of flood disaster, as well as analytic hierarchy process and the approach of combining factors are utilized in the comprehensive assessment and analysis of flood risk in views of hazard and vulnerability of flood disasters. This research shows that this simulation model can forecast the dynamic process of flood inundation with different frequencies of precipitation and make an effective assessment of the risk of flood disaster combined with related socioeconomic attributions, so that it can provide strong support for the reservoir dispatching and flood prevention and alleviation.