武汉汉阳地区城市集水区尺度降雨径流污染过程与排放特征

2005年4月至8月对武汉市汉阳地区十里铺集水区进行了8次径流污染过程的水量、水质研究.结果表明,城市集水区尺度径流污染过程是降雨径流对整个集水区地表、排水系统中累积污染物的冲刷、携带过程,受集水区累积污染物数量、污染物可冲刷性和降雨径流特征的共同影响.城市降雨径流中初期污染物浓度显著高于后期,污染物浓度的峰值提前于径流的峰值,具有明显的初期冲刷效应.8次监测结果的算术平均值,初期5 mm、10 mm和15 mm降雨径流中TSS的负荷分别占总负荷的48%、68%和78%.初期径流中TSS的负荷与晴天累积天数呈线性正相关关系.

Catchment-scale pollution process and first flush of urban storm runoff in Hanyang, Wuhan City

Eight storm events were surveyed at Shilipu catchment in Hanyang, Wuhan City. The flux , total suspended solids (TSS), chemical demand oxygen (COD), total nitrogen (TN), and total phosphorus (TP) in the runoff were measured. From the hydrograph and pollutography analysis, the process of urban stormwater runoff pollution was synchronously effected by the amount and availability of pollutants and the characteristics of rain-runoff. The concentration of pollutants was substantially higher during the initial period of stormwater runoff than lasted period. Based on the average of the eight storm events, 48%, 67%, and 78% of the TSS load were transported in the first 5mm, 10mm and 15mm runoff depth, respectively. The pollution load of the initial runoff was positively related to the dry weather period lasting before.