Mobile QR Code QR CODE : Journal of the Korean Society of Civil Engineers
Title Analysis of Flood Level Changes by Creating Nature-based Flood Buffering Section
Authors 류지원(Ryu, Jiwon) ; 지운(Ji, Un) ; 김상혁(Kim, Sanghyeok) ; 장은경(Jang, Eun-kyung)
Page pp.735-747
ISSN 10156348
Keywords 홍수완충공간; 홍수위변화; 홍수관리시설; 제방후퇴; 자연기반해법 Flood buffer zone; Flood level variation; Flood management facility; Levee setback; Nature-based solution
Abstract In recent times, the sharp increase in extreme flood damages due to climate change has posed a challenge to effectively address flood-related issues solely relying on conventional flood management infrastructure. In response to this problem, this study aims to consider the effectiveness of nature-based flood management approaches, specifically levee retreat and relocation. To achieve this, we utilized a 1D numerical model, HEC-RAS, to analyze the flood reduction effects concerning floodwater levels, flow velocities, and time-dependent responses to a 100-year frequency flood event. The analysis results revealed that the effect of creating a flood buffer zone of the nature-based solution extends from upstream to downstream, reducing flood water levels by up to 30 cm. The selection of the flow roughness coefficient in consideration of the nature-based flood buffer space creation characteristics should be based on precise criteria and scientific evidence because it is sensitive to the flood control effect analysis results. Notably, floodwater levels increased in some expanded floodplain sections, and the reduction in flow velocities varied depending on the ratio of the expanded cross-sectional area. In conclusion, levee retreat and floodplain expansion are viable nature-based alternatives for effective flood management. However, a comprehensive design approach is essential considering flood control effects, flow velocity reduction, and the timing of peak water levels. This study offers insights into addressing the challenges of climate-induced extreme flooding and advancing flood management strategies.