Study On Design Of Rainwater System With Low Impact Development In A College And Guidance Of Rainwater Resources Project In Centralized Residential Area Of Yixing City

In recent years,with the Yixing urbanization process continues to accelerate,frequent urban waterlogging phenomenon,seriously hindered the development of the city.Coupled with the increasing demand for water resources,water pollution has become increasingly serious,Yixing water quality problems highlighted.Rainwater as the culprit of urban waterlogging,but also a clean,economic water resources,rainwater collection and utilization for improving Yixing water environment,promote sustainable development in Yixing is of great significance.The water quality characteristics of 28 runoff and runoff in Yixing City were studied at 2016.04.08?2016.12.23.The results showed that CODMn,SS,TN,TP,NH3-N and NO3--N six pollutants.The results showed that the main pollutants were CODMn,SS and TN,and the highest monthly mean value reached 33.24 mg/L,198.70 mg/L and 9.32 mg/L,respectively.It is recommended that the rainwater be discarded when the rainwater is collected and utilized.When the number of dry days is less than 6 days,the contents of CODMn,SS and TP in the runoff of each surface are increasing slowly.With the increase of the number of dry days,the concentration of pollutants in rainwater runoff is increasing obviously,but still less than that of "surface water environment quality standard"(GB3838-2002)V class limit.Based on the results of on-site monitoring,combined with the actual situation of a college in Yixing City,the rainwater system with low impact on the development of the Institute was designed to collect rainwater in planning areas such as roofs,roads,green spaces,parking spaces,playgrounds and square,to achieve 75%of total annual runoff control rate.The green space is designed as a concave green space,the roof,50%of the road and green rain to collect their own.Parking spaces using pavement pavement,their own rain to absorb.Square with pervious pavement,while a U-shaped line ditch.In addition,the rainwater traps with infiltration and storage of rainwater are used instead of the traditional rainwater ports.The rainwater pipe network is also designed to meet the rainwater harvesting system.The collected rainwater is transported to the rainwater storage tank near the center of the arts.The design "rainwater-the initial rain water discard-grit chamber-transfer pool-filter,disinfection,etc." rainwater treatment process,the initial pollution of the more serious rain water to abandon the flow of water after the sink by the sinking,filtration,disinfection after a series of processing,used for landscape water,green and road pouring.Based on the study on the characteristics of rainwater runoff in Yixing City,this paper draws lessons from the experience of rainwater system development in Yixing University,and draws on a large number of theoretical and practical experiences at home and abroad,and compiles the actual situation of Yixing City Rainwater resources technical guidelines for the Yixing City,the use of rainwater resources to provide theoretical and technical support.