城区路面径流水质特征与初期径流量研究

Research on Water Quality Characteristics and Initial Runoff Amount of Urban Road Runoff

鉴于研究城区路面径流水质特征与初期径流量可为有效利用城市雨水、控制城市非点源污染等提供参考依据,采用污染物分析法对新乡市2010年城区路面3场降雨径流的水文水质过程进行采样分析,水质指标包括pH值、SS、COD和DO。结果表明:径流初期污染严重,主要污染物COD、SS变化趋势基本一致,随着降雨过程的持续含量逐渐降低,趋于一个稳定值;各指标标准差率呈SS>COD>DO>pH值的趋势,这与各自浓度变化过程的指向性一致;径流中COD、SS之间的相关性较好,DO与其之间的相关性较差;场次降雨路面初期径流量可取为前8 mm^10 mm的降雨量或前25 min^30 min的径流量。

Researching on the variation characteristics of pollutants and initial runoff amount of urban road runoff can provide bases for effectively using the urban rainfall and controlling the non-point source pollution, etc. The hydrology and water quality processes of 3 rainfall events on the urban mad of Xinxiang City in 2010 were sampled and analyzed by using the pollutant analysis method. The examples were taken to analyze the contents of pH, SS, COD and DO. The results show that the runoff water quality is bad at the beginning, as the duration of rainfall, the variation trend of main pollutant index COD and SS in runoff is similar and tends to a steady value. The standard deviation rate of water quality indicators is in the order of SS 〉 COD 〉 DO 〉 pH, which is consistent with the directivity of these indicators＇ concentration variation. The correlation between COD and SS is good in runoff, but that is small between DO and these pollutants. The initial runoff amotmt on the road of event rainfall is equivalent to the former 8 mm- 10 mm rainfall or former 25 rnin - 30 rain runoff.