Evaluation And Optimization Of Low Impact Development In Residential District

With the rapid urbanization process in China,extreme weather caused by climate change may lead to flooding and other urban water climate disasters in urban area and endanger the self-regulating ability of the urban water cycling system due to highly concentrated populations and intensively developed urban land in cities.In order to solve the contradiction between the development of residential areas and water resources,this study took the B area of Konggang Garden Community in Xixian New Area of Shaanxi Province as a case,using a model simulation method to assess the current status of flood risk in the study area,and evaluate the ability of runoff control in response to extreme precipitation events between individual and combination low-impact development measures.The main results were as follows:1.Under the extreme rainfall weather scenario,the existing drainage network in the study area developed by the traditional construction model is overloaded and there was a risk of waterlogging.2.The individually deployed low impact development(LID)measures had different time and functional effects in response to extreme rainfall events.Under different recurrence periods,the permeable pavement,rain garden and rain barrel,all had a significant effect in runoff;The peak capacity of vegetative swale was acceptable,but the effect of reducing runoff was not obvious.3.The combined solution of permeable pavement,rainwater garden,vegetative swale and rain barrel was comprehensive and stable.The two types of low impact development combinations were more effective in stormwater control than the individual low impact development measures;the stability of multi-type LID schemes in regulating stormwater was superior to the combination of two LID schemes.4.Based on the characteristics of severe collapsible loess in the study area,the design scale of various measures and multiple combined LID measures were optimized in the plan with the considerations of building safety,environment protection,and feasibility and cost-effectiveness of construction,and designed rainwater reuse system,to maximize the effectiveness of waterlogging prevention and environmental protection.