Abstract: The aim of this research is to enhance our cognition on the details of inundation area in the flood risk display by MIKE FLOOD model, and reflect dynamically the flood propagation process when danger such as a breach occurs. We summarized the existing expression methods of flood risk, examined the fusion and expression methods of flood process in 3DGIS scene, and built a program framework for 3D dynamic derivation of flood risk. With the South Juma River in Xiongan New Area as a case study, we calculated the flood process after the dam break based on the MIKE Flood models, constructed a 3DGIS environment using the Open Scene Graph technology, and analyzed the flood process in a real three-dimensional topography. Result demonstrates that the presented method is prior to conventional 2D method in terms of detail expression and dynamic simulation. It can also describe the inundation process in multiple scales, and reflects the dynamic flood process more intuitively and efficiently.

Key words: flood risk, 3D dynamic deduction, 3DGIS, MIKE model, Xiongan New Area