基于流域系统整体观的城市洪涝治理研究

针对传统城市洪涝治理洪、涝孤立考虑的弊端,在广州市2020年"5·22"特大暴雨洪涝成因分析的基础上,提出了"洪涝同源"的流域系统整体观,建立了统一市政和水利设计雨型的"大包小、长包短"方法,构建了"城市海绵-市政小排水系统-水利大排水系统"耦合的城市洪涝模拟模型。以广州市某区域洪涝治理为例,研究表明,基于流域系统整体观进行工程布局优化,既满足高度城市化地区经济性和约束性原则,也可实现系统治理、整体达标,有效避免了传统洪涝分治模式存在"因洪致涝、因涝致洪"的弊端,为我国城市洪涝治理提供了新思路。

Research on the control measures of pluvial and fluvial urban floods based on holistic view of watershed system

Pluvial and fluvial floods were considered independently in traditional flood disaster prevention. According to the investigation and analysis on flooding occurred in Guangzhou City in May 22, 2020, a new concept, in which the whole river basin is regarded as an integrated system, is proposed in this study. The design rainfall patterns from both municipal authorities and water authorities are integrated as one pattern through the way of "big one include small one,and long one include short one". A simulation model for fluvial and pluvial flooding in urban area is developed by coupling the low impact development facilities, small-scale municipal drainage system, and large-scale hydraulic drainage system. Take the control measures of pluvial and fluvial urban floods in Guangzhou as an example, the case study shows that the control engineering layout optimization based on holistic view of watershed system can not only meet the economic and restrictive principles for highly urbanized areas, but also achieve systematic governance and reach the overall standards. It effectively avoids the disadvantages of "fluvial flooding caused by pluvial flooding and vise versa" in the traditional flood divide-management mode, which provides a new approach for urban flood management in China.