Design of Runoff Collection System of Expressway across Water Sensitive Areas

If pavement runoff formed by the rain washed road surface pollutants is directly discharged while not be treated, the surrounding environment, especially receiving water will be subject to damage. The expressway inevitably passes through water sensitive areas sometimes. In order to avoid polluting water source, pavement runoff needs to be treated and pollutant control index meet Environmental Quality Standards for Surface Water (GB 3838-2002) in China before being discharged. Aiming at drainage design of expressway across water sensitive areas, this paper has illustrated drainage design concept of collecting independently rain on pavement and slope and solved some problems in process of designing runoff collection system of expressway across water sensitive areas. The results of this research will provide reference for the related engineering examples.