Application of Bio-Retention Hydrologic Performance Tool for Urban Runoff Pollutants Removal

To achieve more reasonable and effective treatment of urban stormwater, researchers proposed the Low Impact Development (LID) method, which is regarded as a sustainable solution. Studies have shown that the bio-retention system was effective in tackling urban runoff problems and was one of the most commonly used LID. In hydrologic modeling, DRAINMOD has a new application in bio-retention simulation. A model named Hydrologic Performance Tool (HyPer Tool) is proposed based on the output of DRAINMOD simulations on various bio-retention designs. This paper utilized HyPer Tool to simulate the bio-retention system in the urban road runoff in Xi'an, China with different rainfall conditions and characteristics. Meanwhile, this paper discussed and analysed the dynamic changes of pollutants and impurities during bio-retention system runoff purification in the four typical designs of HyPer Tool bio-retention ponds so as to provide an objective evaluation on bio-retention - an urban rainfall-flood management approach.