Evaluating the Impact of Low Impact Development Practices on the Urban Flooding over a Humid Region of China

Abstract

ABSTRACTGlobal warming and the rapid development of urbanization increase the likelihood of the occurrence of urban inundation, causing serious economic losses and threats to people's lives. Low impact development (LID) practices have attracted increasing attention as an effective approach which can mitigate urban inundation to some extent. Investigating the impact of LID practices on urban inundation is of significant importance to the prevention and control of urban flooding. This study constructed a coupling model with the combination of Storm Water Management Model and a 2D hydrodynamic model to provide a comprehensive simulation of urban inundation. The inundation situations are simulated with various scenarios by considering the implementation of LID practices under various rainfall return periods in Wuhan, China. We found that the LID practices can be more effective for urban inundation mitigation under rainfall events with smaller magnitude, and its ability in reducing the flood risk is weakened for extreme rainfall events. The results showed that LID practices can reduce the inundation area by 22.52%–38.9%. Especially for the inundation area with water depth larger than 0.4 m, the LID practices can reduce the inundation area by 71.52%–88.73% under different scenarios. Besides, the LID practices have a certain impact on the inundation area affecting traffic with a reduced rate of 37.2%–90.06%. This study can provide scientific support and a potential guiding significance for the future implementation of LID practices in cities under similar construction conditions.