Author(s): Yongwon Seo, Junshik Hwang, Youjeong Kwon
Linked Author(s): Yongwon Seo
Keywords: Directly connected impervious area, width function, green infrastructure, drainage network, hydrograph
Abstract: The concept of directly connected impervious area (DCIA) or efficient impervious area (EIA) refers to a subgroup of impervious cover, which is directly connected to a drainage system or a water body via continuous impervious surfaces. The concept of DCIA is important in that it is a better predictor of stream ecosystem health than total impervious area. DCIA is a key concept for a better assessment of green infrastructure that is drawing more attention recently since DCIA has a direct relation with green infrastructures in urban environments. In this study, we evaluated several methods to calculate the DCIA based on a precise GIS database and showed the importance of the accurate measurement of DCIA in terms of resulting hydrographs. We also combined the width function-based instantaneous hydrograph with the concept of DCIA to evaluate the potential green infrastructures that can be introduced in the test catchment in South Korea. The results showed that the changes of DCIA, by green infrastructures, directly affect the shape of hydrographs and decreases peak flows. These results imply that we can introduce well-planned green infrastructure to urban catchments for flood risk managements and quantitative assessment of spatial distribution of DCIA is crucial for this
Year: 2017