Patterns and Trends of Water Level and Water Quality at the Namgang Junction in the Nakdong River Based on Hourly Measurement Time Series Data

낙동강 남강 합류부 수위와 수질 패턴 및 추세

  • Yang, Deuk Seok (National Institute of Environmental Research, Nakdong River Environment Research Center) ;
  • Im, Teo Hyo (National Institute of Environmental Research, Nakdong River Environment Research Center) ;
  • Lee, In Jung (National Institute of Environmental Research, Nakdong River Environment Research Center) ;
  • Jung, Kang Young (National Institute of Environmental Research, Nakdong River Environment Research Center) ;
  • Kim, Gyeong Hoon (National Institute of Environmental Research, Nakdong River Environment Research Center) ;
  • Kwon, Heon Gak (National Institute of Environmental Research, Nakdong River Environment Research Center) ;
  • Yoo, Je-Chul (Department of Environment Engineering, Kumoh National of Technology) ;
  • Ahn, Jung Min (National Institute of Environmental Research, Nakdong River Environment Research Center)
  • 양득석 (국립환경과학원 낙동강물환경연구소) ;
  • 임태효 (국립환경과학원 낙동강물환경연구소) ;
  • 이인정 (국립환경과학원 낙동강물환경연구소) ;
  • 정강영 (국립환경과학원 낙동강물환경연구소) ;
  • 김경훈 (국립환경과학원 낙동강물환경연구소) ;
  • 권헌각 (국립환경과학원 낙동강물환경연구소) ;
  • 유제철 (금오공과대학교 환경공학과) ;
  • 안정민 (국립환경과학원 낙동강물환경연구소)
  • Received : 2017.11.16
  • Accepted : 2018.02.05
  • Published : 2018.02.28


As part of the Four Major Rivers Restoration Project, multifunctional weirs have been constructed in the rivers and operated for river-level management. As the weirs play a role in draining water from tributaries, the aim of this study was to determine the influence of the weirs on the water level of the Nam River, which is one of the Nakdong River's tributaries. Self-organizing maps (SOMs) and a locally weighted scatterplot smoothing (LOWESS) technique were applied to analyze the patterns and trends of water level and quality of the Nakdong River, considering the operation of the Changnyeong-Haman weir, which is located where the Nam River flows into the Nakdong River. The software program HEC-RAS was used to find the boundary points where the water is well drained. Per the study results at the monitoring points ranging between the junction of the two rivers and 17.5 km upstream toward the Nam River, the multifunctional weir influenced the water level at the Geoyrong and Daesan observation stations on the Nam River and the water quality based on automatic monitoring at the Chilseo station on the Nakdong River was affected strongly by the Nakdong River and partly by the Nam River.


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