Application of low impact development technology in rainwater drainage system reconstruction project

Urban roadway contributing much to the runoff and non-point source pollution in modern cities is one of the key objectives when conducting stormwater management in Sponge City construction, which was recently launched by Chinese government. In the present case study, Qinhuang Avenue ( $$\hbox {length}\times \hbox {width}=2.4\,\hbox {km}\times 80~\hbox {m}$$ ) from Xixian New Area in northwest China was chosen as the research objective. The current limitations within the rainwater drainage system of Qinhuang Avenue were analyzed as well as its environmental background (such as the structure and permeability of the wet-sunk loess). Under the premise of maintaining roadway safety and taking the horizontal and vertical line into consideration, low impact development (LID) technology was applied for the design and planning of the reconstruction project according to the principle and requirement of LID technology. The implementation results of the project indicated that waterlogging and flooding issues in the object region were obviously resolved and environmental capacity was improved as evidenced by the reduced volume, peak value and contaminants concentration of total runoff.