Author(s): Seojun Kim; Jihye Kim; Byungman Yoon; Un Ji
Linked Author(s): Byungman Yoon, Un Ji
Keywords: Hydraulic monitoring; Kyungan River; Nature-friendly river improvement; Riverbank erosion
Abstract: Recently, the paradigm of river improvement has been changed so that many efforts are made to improve the environmental function of rivers. The nature-friendly river improvement works should be designed and constructed so to be environmentally sound and physically stable. However the manuals or guidelines are not well-developed yet to satisfy these purposes. Therefore, hydraulic changes should be analyzed through monitoring works to examine that various methods applied to nature-friendly river improvement works are maintained for design purposes. In this study, physical changes of bed degradation and aggradation, lateral channel movement, and bed material changes and hydraulic stabilities of riverbanks, levees, drop structures, riffles, and groynes applied in river improvement works for Kyungan River are analyzed based on the monitoring results. The Kyungan River of study area is the biggest tributary of Han River. It originates at DongMyun, Youngin-Si, Kyunggi-Do and flows into Paldang Lake. Since Kyungan River and Paldang Lake are located near metropolitan area of Seoul, water quality has been degraded and ecosystems in the stream corridor have been damaged due to population growth and inconsiderate development. The government, therefore, began to make efforts to improve fluvial environments around Paldang Lake. The nature-friendly river improvement work for Kyungan River is one of their efforts. The environment-improvement project of the Kyungan River was initiated in May 2001 and completed in April 2004. Main purpose for this project was to improve the river environment including water quality and ecological habitat as well as geomorphologic and hydraulic stabilities. The monitoring has been carried out since the beginning of the project and continued after the completion of the construction work. The monitoring results indicated that the bed elevation is increased and the riverbank in the meander bend is eroded between inclined groynes installed using riprap to prevent riverbank erosion. Monitoring works are necessary to propose remediation methods as well as to examine the hydraulic stability.
Year: 2010