Flood Hazard Evaluation and GIS in Guangzhou

The author used both the analytic hierarchy process (AHP) and the factor superposition method to evaluate flood risk and vulnerability of environments subject to continuous hazards in areas and districts of Guangzhou. Natural environmental flood risk factors were evaluated as was the subsequent level of vulnerability to human activities in each area in Guangzhou. To express its spatial relationships, a Flood Hazard Evaluation map was created using GIS software. Analysis of the results produced the following conclusions: flood hazard intensity in Guangzhou is higher in the south and lower in the north; considered from west to east, western and eastern areas have a higher flood hazard intensity while the city´s center is low. These findings are related to central Guangzhou being dominated by mountains and no major rivers, while the western and eastern areas consist of low-lying areas with many rivers and streams. Results from this study should serve as baseline information both for flood prevention and for its mitigation in Guangzhou and similar cities.