The Planning Research On Drainage System Of A River Basin In Shenzhen Based On SWMM Model

With the speeding up of urbanization,the problem of urban waterlogging is becoming more and more serious.To solve this problem,this paper innovatively has taken a large scale basin-A River Basin in Shenzhen as an example,chosen the SWMM model as the simulation model,and the basic data were processed and analyzed by ArcGIS.The study area was divided into 324 sub-catchment areas,3304 water collection wells,790 stormwater discharge wells and 3379 pipelines,which constructs SWMM model of Maozhou River Basin's drainage system.And using the constructed model,the hydraulic and water quality simulation of the local drainage system is completed.The conclusions is as follows:(1)In this paper,the principle of SWMM simulation model are analyzed and discussed,specifically the principle of surface runoff yield in simulation,modeling and surface contaminants accumulated erosion model to simulate the principle and model parameter calibration method.Taking the a River Basin of Shenzhen as an example,the generalization of sub-catchment area,the generalization of drainage network system and the determination of model parameters were carried out.The SWMM model was established.(2)Based on the SWMM model,the drainage network model of the River Basin in Shenzhen was established.The drainage capacity of the existing drainage network was evaluated,and the waterlogging point and overloaded pipes under typical storms were found out.And the overall planning method and idea of drainage system of the River Basin in Shenzhen was put forward.(3)According to the results of the SWMM simulation study,the innovative scheme of building "Blue Roof" of the studied river basin was put forward according to the local planning and sponge city,and a comprehensive plan of the drainage system planning of the study area was put forward from the drainage network system,LID and road drainage aspects.(4)According to the planning scheme,the effect of the planning is evaluated separately.The results show that the construction of pipe network alone is not enough to deal with heavy rainfall,which means LID measures and road drainage are needed.LID measures mainly handle weak rainfall scenarios.When the intensity of rainfall exceeds the capacity of LID measures,it needs road drainage to deal with the heavy rainfall.Finally,the comprehensive planning proposed in this paper has presented good performance.