Studies on establishing flood control and drainage dispatch model system in Tianjin

Li Min; Zang Wenbin; Wu Binbin; Zheng Jingwei; Zhang Minghui; Li Kuang; Liu Shu

doi:10.3969/j.issn.1000-1123.2025.04.007

Abstract：Nowadays,floods have become the main natural disasters in cities of China.The measure of"flood forecasting,early warning,rehearsal and contingency plan"has played a key role for cities to cope with flood and waterlogging,by using urban flood simulation technology as its key support.Being a coastal city,Tianjin faces a significant threat of upstream flooding,with prominent drainage pressure in the city central areas.There is a risk of flash floods in the northern mountainous areas,while downstream areas are affected by seawater intrusion,resulting in complex and severe flood and waterlogging problems.Currently,there are difficulties in establishing flood control and drainage dispatch model system in Tianjin,because the scope of model is constrained by factors such as forecast period,amount of computation and data acquisition.External and internal floods interact with each other,but each has its own stress.Plain river network and water system are complicated,with various types of structures for dispatching and scheduling.Meanwhile,flood management requires high precision and timeliness of model results.In response to this,a flood prevention model was developed at three scales of coverage area,urban flood control circle and downtown area,with consideration to model scope,simulation method selection and simulation object combination.Regional models integrates hydrological and hydrodynamic models for zoning modeling,while urban flood control circle models are expanded to clarify boundary conditions.The central urban area model is coupled with multiple models based on the former.This model can support coordinated scheduling of complex structures on a large scale,different business application scenarios,and overall evaluation of external and internal floods.