Investigation And Analysis On Water Quality And Quantity Of Separate Storm System In ChaoHu City

With the rapid urbanization, point source pollution is of control, while non-point source pollution turns into a serious threat to urban water resource, people began to pay attention to the problem of non-point source pollution. The runoff pollution is the main effect to the urban non-point pollution. While water resource is seriously shortage in nowadays, rainwater is the one of available fresh water which may be used to alleviate the shortage of urban water, it is meaningful to the the use of urban water. To grasp the change rule of the quality and quantity in runoff water, which is a necessary prerequisite to control the non-point pollution.This text had monitored5times rainfall from separate storm water system in dongtang road,ChaoHu. While the result of experiment and monitor shows that the rainwater had been seriously polluted in separate storm system., especially in the early period runoff, the concentration of pollutant is even higher than life waste water, the early period runoff is in30minutes at most. During the process of rainfall, the concentration of pollutants is further reduce and eventually stabilize. There are the same change tendency in pipe flow and rainfall intensity, but there is a certain catchment time, the change of pipe flow was behind the rainfall intensity.To analysis the correlation between each pollutant of rainwater runoff, it shows that COD and TP have some relation with SS. To calculate the result from each rainfall got the value of EMC.To analysis the correlation between EMC and precipitation, it shows that there is a negative correlation between EMC and precipitation. This text has used M(v) curve and the b parameter method to analysis the first flush effect, the result shows that each pollutant have first flush effect, but the first flush effect is not evident.The runoff water in urban has been seriously polluted,use for reference of the "Best Management Practices"(BMPs) which have been put forward by USA. To control and cut down runoff pollution from rainy day by project and non-project measures.Not only to improve the urban water environment, but also to use the rainwater resource effective.and then remission the shortage of urban water resource.