An Effectiveness Study on the Use of Different Types of LID for Water Cycle Recovery in a Small Catchment

Low-Impact Development (LID) is alleviating the water cycle problems that arise from an increasing impervious surface area caused by urbanization. However, there is insufficient research on the application and analyses of LID techniques that are used for studying the management goals for water cycle restoration. The present study applied various LID techniques, utilizing the stormwater management model (SWMM) in the Naju-Noan Waterfront Zone Construction Project and studying its effects, aiming to restore the runoff that had increased due to urbanization to its pre-development state. The five LID techniques used in the analysis were permeable pavements, bioswales, rainwater gardens, green roofs, and planter boxes, which took up 36.2% of the total area. Our analysis showed that development increased the runoff rate from 39.4% to 62.4%, and LID reduced it to 34.7%. Furthermore, development increased the peak flow from 0.77 m(3)/s to 1.08 m(3)/s, and the application of LID reduced it to 0.78 m(3)/s. An effective reduction in the runoff and peak flow was shown in every recurrence period that was tested, and the bioretention cell type of LID showed the best effectiveness per unit area compared with permeable pavements and green roofs.