Research Of Runoff Storage Conditions Of Rainwater Garden

In the process of urban development,A large area of road construction has changed Urban original path of surface runoff and the Infiltration process,blocking the surface water leakage path,causing floods,water pollution and destruction of aquatic environmental,the rainwater garden-a new type rainwater system of ecological comprehensive utilization,can fully use of rainwater resources,playing a role in retention reducethe surface rainwater peak,realizing the maximization of the rain water infiltration,to prevent the occurrence of the floods.This paper selected the test site of a built rainwater garden system of Chengdu as the research area to perform the experimental study,Analyzing the rainwater runoff,infiltration process and rainwater drainage system structure of rain garden system.Simultaneous monitoring of local rainfall,the flow of discharge pipe and changes of water storage level in rainwater garden.With controlled trial,Analyzing the runoff regulation process of rainwater garden system,comparative analyzing Underground seepage of storm runoff and operation condition of pipeline leakage,to evaluate the storage capacity of rainwater garden,and obtained the following research results:(1)A calculation model of runoff storage rainwater garden system is established,analyzing the operation process of rainwater garden system,comprehensive monitoring data and simulation results,verified the rainwater garden system had obvious stagnant rainwater storage function.And aiming at the rainfall pattern with higher rainfall intensity and shorter rainfall duration,the model is in good agreement with the actual test system of rain garden the rainfall intensity,rainfall duration is relatively short rain type storage effect is more obvious,it is more representative,and the storage effect is more obvious.(2)6 rainfall events which are in good agreement were selected to evaluate the storage,the drainage function of rainwater garden system were evaluated by calculating the effect of runoff reduction,the total reduction rate is in the range of 40.28%?69.84%,the average value is 61.31%,the maximum value is 93.66%,appeared in July 22nd.(3)Calculated by the model system and condition analysis results,in 9 rainfall,runoff water peak flow don't exceed the design limits.The storage capacity of rainwater garden meets the needs of typical rainfall runoff regulation and storage,system operation condition is normal,the system design is in high stability.