The performance of LID (low impact development) practices at different locations with an urban drainage system: a case study of Longyan, China

Abstract

Urbanization has strongly changed the condition of the land surface and therefore rainfall runoff varies greatly. Peak flood flow and flood volumes increase with runoff volume. Low Impact Development (LID) is a sustainable concept that minimizes the effects of urbanization to maintain natural hydrological function in urban cities and has therefore gained increasing attention. This paper studies the effects of low impact development measures on the reduction of runoff generation and peak runoff at different locations in Longyan, China. The study was conducted using the SWMM model (5.1.006) with a newly developed LID module. In this study, the LID module, which includes rain gardens, green roofs, permeable pavements, and rain barrels, was used to simulate different layout scenarios and different rainfall patterns. The results show that the performance of a certain LID is similar at different locations but the reduction effect on runoff and peak flow varies. Rain gardens and permeable pavements perform a similar degree of reduction under different durations, but the peak flow reduction by rain barrels and green roofs varies greatly. Further research should focus on composite LID applications in other locations, combination with the local pipe network layout, which will ensure that the implemented system will be aesthetically pleasing, economically viable, and effective for reducing runoff and peak flow.