Model Assessment Of Harvesting Rainwater Green Spce

China has begun on the exploratory construction work Since 2014,due to frequent urban waterlogging and serious water shortages in northern and southern cities.To Landscape architecture industry,"Sponge city" has both advantages and disadvantages as well as opportunities and challenges.Harvesting rainwater green space is an important part in the development of "sponge city".The design and construction of harvesting rainwater green space is guided by Landscape architecture industry and finished by the cooperation of different professions.For the lack of scientific assessment measures,some relevant work cannot be controlled scientifically in current design and construction.This article explores the assessment objects and evaluation methods of harvesting rainwater green space design from the point of greenbelt assessment and model assessment,and takes Zizhuyuan Park as an example to carry out the practice test,From the angle of model assessment on harvesting rainwater green space design,the middle layers and the index layers are established based on relevant research data.Through the analytic hierarchy process and the Delphi method,the important assessment factors are selected out:Rainfall infiltration,post-rain infiltration,peak flow time,green water total,water storage emptying time,SS reduction rate,COD reduction rate,TN reduction rate,TP reduction rate,rainwater utilization,return rate of rainwater using,rainwater emissions,runoff control rate.At the same time,all the assessment factors are quantified by means of software SWMM combined with the GIS model and "cost-benefit" model of economics.According to relevant research theory,the actual simulation was carried out in Beijing Zizhuyuan Park,setting one year as recurrence period,Chicago rainfall model as rainfall model.It shows that Zizhuyuan Park has made certain achievements on rainwater runoff control,peak flood flow control and rainwater utilization,while it still has problems on solving rainwater pollution and discharged boundary rainwater.In view of the assessment results,this article puts forward specific promotion strategies on improving park boundaries and adding purification measures.