Characterization of Stormwater Runoff Pollution in Mountain City

Taking indicators the case of an university campus runoff quality in Main Urban Area of Chongqing,three kinds of stormwater runoff quality were monitored,where indicators included pH,suspended Solids(TSS),chemical oxygen demand(COD),ammonia-nitrogen(NH3-N),total phosphorus(TP),and so on.The results show that the average concentration of stormwater runoff pollutants exceed the fifth level of the environmental quality standards for China except TP,SS concentration of runoff can reach 1 730 mg/L,COD and NH3-N concentration of runoff can reach 76.25 mg/L and 3.67 mg/L;First flush takes effect evidently,and SS、COD、NH3-N first flush concentrations of concrete road surface were 2330mg/L,106.4mg/L,5.64mg/L.First flush concentrations were equivalent to 2-4 times of Event Mean Concentrations(EMCs),and the highest concentration value of pollutants appeared when runoff produced 10~15 minutes later.Comparison on runoff quality of three different rainfall intensity,higher intensity was positively correlated with TSS,COD,NH3-N,and TP concentrations,among which rainfall intensity taked greatest effect on runoff pollutants concentration of large slope road.