Abstract: The combined effect of global warming and the urban rain island effect has exacerbated the spatiotemporal heterogeneity of extreme precipitation events,which poses a major pressure on the resilience of urban drainage systems. Based on the topography,climatic characteristics and current status of drainage facilities in the central urban area of Ankang,this study systematically analyzes the formation mechanism of waterlogging risk,and proposes multi-dimensional optimization strategies covering planning coordination,facility upgrading,management coordination and emergency support. By integrating the concept of sponge city （Low Impact Development,LID）,the cross-departmental dynamic risk assessment model and the joint prevention and control mechanism of rainfall in the Hanjiang River Basin,a three-in-one sustainable development framework of “disaster prevention,mitigation and resilience” of cities along the river in mountainous areas was constructed,providing experience for the optimization of flood control systems in similar cities.

Key words: extreme precipitation, drainage system, risk management, low impact development （LID）, resilient cities