An integrated assessment of urban flooding risk and resilience based on spatial grids

During heavy rainfall events, stormwater exceeds the drainage capacity and overflows onto the urban surface, causing flooding problems. Risk and resilience assess the severity and recovery characteristics of flooding damage from static and dynamic perspectives independently. This work proposes a spatial grid-based integrated risk-resilience assessment framework for urban flooding to consider both flooding risk and resilience aspects at a detailed level. The framework formulates an urban drainage-surface coupled model to simulate the inundation process. A risk-resilience classification method is proposed to identify the flood-affected characteristics of each grid, with flooding risk and resilience values considering socio-economic characteristics and step-by-step inundation dynamics. According to case results and discussion, the grid-based classification classifies all the grids into four types with different risk and resilience levels, in which 7.02% grids are identified as the worst type with high risk and low resilience. The assessment framework enables detailed-level targeted management for urban flooding problems.