Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
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Stratified features in Paldang lake considering induced density currents and seasonal thermal effect

유입하천 밀도와 계절별 수온을 고려한 팔당호 성층 해석

  • Choi, Suin (Department of Civil & Environmental Engineering, Dankook University) ;
  • Kim, Dongsu (Department of Civil & Environmental Engineering, Dankook University) ;
  • Seo, Ilwon (Department of Civil & Environmental Engineering, Seoul National University)
  • 최수인 (단국대학교 토목환경공학과) ;
  • 김동수 (단국대학교 토목환경공학과) ;
  • 서일원 (서울대학교 건설환경공학부)
  • Received : 2023.10.09
  • Accepted : 2024.01.24
  • Published : 2024.02.29
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Abstract

Paldang Reservoir serves as a crucial water source for the metropolitan area, and national efforts are focused on water quality management. The region near Paldang Dam, where the water intake facility with the greatest depth is located, experiences vertical stratification during the summer. It has been challenging to definitively classify whether this stratification is caused by density currents or summer temperatures. This study aimed to differentiate and analyze stratification due to density currents and temperature variations at key locations in the Paldang Reservoir through vertical water quality measurements. The results allowed us to distinguish between density current and temperature-induced stratification. We found that density currents are primarily caused by temperature differences among inflowing rivers, with flow velocity significantly influencing their persistence. Additionally, based on a combination of monsoon and non-monsoon season characteristics, we classified Paldang Reservoir into regions with distinct river and lake traits.

팔당호 취수장은 수도권 주민에게 상수원을 공급하는 주요 취수장으로, 상수원의 수질 관리를 위해 국가 차원에서 노력을 기울이고 있다. 팔당댐 취수장 인근의 수심이 가장 깊은 지역은 여름철에 연직 방향으로 성층이 발견되는데, 성층의 원인이 밀도류에 의한 것인지 여름철 기온에 의한 것인지 명확하게 분류하기 어려운 실정이다. 본 연구에서는 팔당호 주요 지점의 연직 수질 측정을 통해 밀도류에 의한 성층과 기온에 의한 성층을 분류하고, 발생 원인을 분석하였다. 연구 결과로는 밀도류와 기온에 의한 성층을 구분하였으며, 밀도류의 형성은 유입 하천 간 수온 차이에서 기인하는 것으로 확인되었지만, 밀도류의 지속 거리는 유속에 크게 의존하는 것으로 나타났다. 또한, 갈수기와 풍수기 혼합 특성을 기반으로 하천형과 호소형 특성을 가진 지역으로 팔당호를 분류하였다.

Keywords

Acknowledgement

본 연구는 환경부 미세플라스틱 측정 및 위해성 평가 기술개발사업(202100311003)의 연구비 지원에 의하여 연구되었으며 이에 감사드립니다.

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