北京市城市屋面径流特征研究

对北京市城区不同功能区和不同类型的屋面进行三场降雨径流监测,并分析屋面径流污染过程和水质特征。采用降雨径流污染物平均浓度(EMC)分析评价径流污染程度,结果表明径流水质与屋面材质、降雨强度等因素有关,沥青屋面污染较重,降雨强度越大,径流水质越差;三场降雨中污染物浓度随降雨历时总体上呈先升高后降低的变化趋势,初期径流水质较差,存在明显的初始冲刷现象。

Study on the Variation of Urban Roof-Runoff Pollution

In this research, we carried out three tests of roof runoffs of different types at different functional districts in the urban area in Beijing, and analyzed the pollution processes of roof runoffs as well as water quality of roof runoff by event mean concentration (EMC). The results show that water quality of roof runoff is correlated with the texture of roofs, the intensity of precipitation, and other factors: asphalt roofs produce the heaviest pollution; besides, the heavier the rain, the worse the water quality of runoff. In the three tests we conducted, pollutant concentration generally first rises and then decreases as precipitation continues. Water quality of roof runoff is low during the early phase, and First flush effect is easily observed.