The Form and Distribution of Heavy Metals from Highway Runoff in Shanghai

Sampling and monitoring of five rainfall-runoff events from a highway in Shanghai were conducted to characterize particle size distribution and heavy metals content in different particle size.The results indicate that the dominant particles ane of less than 250 μm in all the samples.The main forms of pollutants discharge are particle-bound Pb,Zn,Cu,Ni.Analysis of the effects of first flush finds that the SS and heavy metals all show significantly first flush.Most of the SS and heavy metals can be removed from highway runoff by intercepting and treating the first 20% to 30% of the runoff.Therefore,removal of SS is the effective way to control pollution of heavy metals from highway storm water in Shanghai.