Analysis on characteristics of stormwater runoff flush on different land surfaces
不同地表雨水径流冲刷特性分析

Selected stormwater runoff from typical land surfaces(at campus,cycle way,business street and viaduct) in Beijing as the research objects,characteristics of stromwater runoff in different land surfaces were analyzed.The results showed that the first flush phenomenon of different land surfaces were very obvious.Controlling 20% of the initial stormwater,it is possible to remove 40%~60% of the pollutant total quantity.COD,SS and TP concentrations in the viaduct initial stromwater runoff were the highest,and the highest concentration of TN was from the campus initial stromwater runoff.For different land surfaces,the superior sequence of stromwater runoff water quality was followed: campus,business street,cycle way,viaduct.The particle size of D50 and D90 were almost equal during the entire rainfall process of the campus and cycle way,which were about 30 μm and 50 μm,separately,and the variation range was small.For the business street and viaduct,the particle size of D50 and D90 decreased obviously in initial rainfall,but they had markedly fluctuation in the later period,and the partical size was significantly greater than that from the campus and cycle way.The research results will play an important role in the control of urban stormwater runoff pollution of different land surfaces and sites development.