Flood submergence simulation and risk analysis based on GIS in plain area

A grid-based GIS approach to flood submergence simulation and risk analysis was proposed using an integration of GIS, telemetering stage and high resolution remote sensing image (ALOS), in southeast plain of Yinzhou district. The digital elevation model (DEM) was created based on 1:10000 topographic maps and 1:5000 thematic maps, and several pre-processing methods, including depression filling, urban terrain and river network correction, were applied. After that, the “source flood” algorithm based on visiting every node of the stack, was adopted to simulate the scope and depth of the inundation with DEM and real-time stage data from the telemetry stations. Finally, flood risk was evaluated by taking the factors of flood submergence depth and hazard-affected body. The combination of the real time flood simulation and risk analysis provides an effective decision-making and disaster assessment for the study area.