In order to reduce the potential hazard of life and property loss, research on the flood emergency management is very
important. A flood impact assessing methodology was proposed and examined in Qingshan reservoir. The key
technologies include the flood routing simulation based on 2D hydrodynamic model, and flood losses assessment
based on GIS cell. The 2D hydrodynamic model can quickly calculate flood submerged area, flood water depth
distribution and flood routing time. The flood information could improve efficiency of flood emergency management
and could offer more help in risk indications. The research results provide a powerful tool to analyze flood risk
rapidly and make schemes for the flood resisting.