Scenario simulation and risk assessment of urban flood in Donghaochong basin Guangzhou
摘要
This study developed an intuitive and reliable urban flood-risk zoning map for scientific decision-making by departments related to urban flood control and drainage. The Donghaochong (DHC) basin of Guangzhou city was the study area. A 1 D-2 D coupled urban flood simulation model was constructed based on InfoWorks ICM to obtain disaster-causing factor data by simulating the flood process under the rainstorm return periods of 1 a,5 a,and 50 a. This study also investigated the surveyed areas of hazard-inducing environment,hazard-bearing body,and hazard prevention and mitigation capacity. Risk assessment of flood disasters was carried out in combination with the analytic hierarchy process (AHP),assessment grade,and threshold value division. The results revealed that the urban flood simulation model had good accuracy and reliability in the 1 D drainage system and the 2 D ground submergence simulation,thus ensuring the reliability of the disaster-causing factor data. Also,the risk-zoning map adequately reflected the risk distribution within the basin;moreover,as the return period increased,medium-high risk zones and high risk zones increased significantly,requiring flood prevention and drainage.