취수 수심이 합천호의 수온성층과 방류 수온에 미치는 영향 모델링
Modeling the Effect of Intake Depth on the Thermal Stratification and Outflow Water Temperature of Hapcheon Reservoir
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1970~1980년대 준공된 우리나라의 다목적댐 저수지에는 발전방류를 위한 고정식 취수구가 심층에설치되어 있어 일부 댐 하류에서는 냉수 방류에 의한 농작물 냉해, 안개 일수 증가 등의 문제점이 제기된 바있다. 본 연구에서는 고정식 취수구를 통해 심층 취수가 이루어지고 있는 합천호를 대상으로 취수 수심이저수지의 수온 성층 구조와 방류 수온에 미치는 영향을 분석하였다. 3차원 수리수질모형인 AEM3D를 이용하여 합천호의 연직 수온 분포를 재현하고 계절별 수온성층 구조를 분석하였으며, 수문 조건에 따른 수온성층 변화를 비교 분석하기 위하여 풍수해와 갈수해를 대상으로 모델링 하였다. 또한 취수심 변경 시나리오를적용함으로써 취수 수심이 수온성층 구조에 미치는 영향을 분석하였다. 모의 결과 심층 취수를 표층 취수로변경할 경우 수온약층의 형성 위치가 풍수해 6.5 m, 갈수해 6.8 m 감소하여 더 얕은 수심에 형성될 것으로분석되었다. 또한 수체 안정도 지수인 Schmidt Stability Index (SSI)와 Buoyancy frequency (N2 )가 증가하여 수온성층 강도가 증가하는 것으로 나타났다. 표층 취수시 연평균 방류수온이 풍수해 3.5℃, 갈수해5.0℃ 증가하여 하류하천의 영향은 감소하나, 호내의 저수온층 수체적과 수온성층 강도가 증가하므로 추후 수질관리를 위해 취수심을 댐 운영의 주요인자로 고려해야 할 것으로 판단된다.
Abstract
Korea’s multi-purpose dams, which were constructed in the 1970s and 1980s, have a single outlet located nearthe bottom for hydropower generation. Problems such as freezing damage to crops due to cold water discharge and an increase the foggy days have been raised downstream of some dams. In this study, we analyzed the effect of water intake depth on the reservoir’s water temperature stratification structure and outflow temperature targeting Hapcheon Reservoir, where hypolimnetic withdrawal is drawn via a fixed depth outlet. Using AEM3D, a three-dimensional hydrodynamic water quality model, the vertical water temperature distribution of Hapcheon Reservoir was reproduced and the seasonal watertemperature stratification structure was analyzed. Simulation periods were wet and dry year to compare and analyze changes in water temperature stratification according to hydrological conditions. In addition, by applying the intake depth change scenario, the effect of water intake depth on the thermal structure was analyzed. As a result of the simulation, it was analyzed that if the hypolimnetic withdrawal is changed to epilimnetic withdrawal, the formation location of the thermocline will decrease by 6.5 m in the wet year and 6.8 m in the dry year, resulting in a shallower water depth. Additionally, the water stability indices, Schmidt Stability Index (SSI) and Buoyancy frequency (N2 ), were found to increase, resulting in an increase in thermal stratification strength. Changing higher withdrawal elevations, the annual average discharge watertemperature increases by 3.5℃in the wet year and by 5.0℃in the dry year, which reduces the influence of the downstream river. However, the volume of the low-water temperature layer and the strength of the water temperature stratification within the lake increase, so the water intake depth is a major factor in dam operation for future water quality management.
참고문헌 (35)
- Beutel MW, "Effects of aerobic and anaerobic conditions on P, N, Fe, Mn, and Hg accumulation in waters overlaying profundal sediments of an oligo-mesotrophic lake", Water Research, 42(8-9), pp.1953~1962 (2008)
- Dissolved-oxygen depletion and other effects of storing water in Flaming Gorge Reservoir, Wyoming and Utah, "Bolke EL", Geological Survey, 34~35, pp.Water-supply paper 2058 (1979)
- Caissie D, "The thermal regime of rivers : a review", Freshwater Biology, 51(8), pp.1389~1406 (2006)
- Carr MK, "Impacts of varying dam outflow elevations on water temperature, dissolved oxygen, and nutrient distributions in a Large Prairie Reservoir", Environmental Engineering Science, 37(1), pp.78~97 (2020)
- A Review of artificial destratification techniques for cold water pollution mitigation, "Chaaya FC", UNSW Water Research Laboratory, 1~47 (2021)
- Chung SW, "Modelling the propagation of turbid density inflows into a stratified lake: Daecheong Reservoir", Korea. Environ. Model. Softw, 24, pp.1462~1482 (2009)[DOI]
- 정세웅, "탁수조절을 위한 소양호 선택취수설비 설치 효과 분석", 한국물환경학회지, 27(6), pp.743~753 (2011), 한국물환경학회
- Clarkson RW, "Temperature effects of hypolimnial-release dams on early life stages of Colorado River Basin big-river fishes", Copeia, 2, pp.402~412 (2000)
- Duka MA, "Mediating the effects of climate on the temperature and thermal structure of a monomictic reservoir through use of hydraulic facilities", Water, 13(8), pp.1~18 (2021)
- Duka MA, "Thermal stratification responses of a monomictic reservoir under different seasons and operation schemes", Science of the Total Environment, 767, pp.1~15 (2021)
- Gray R, "Mitigation of cold-water thermal pollution downstream of a large dam with the use of a novel thermal curtain", River Research and Applications, 35(7), pp.855~866 (2019)
- Energy production and reservoir water quality, "Higgins J", American Society of Civil Engineers, ~ (2007)
- 한종수, "고빈도 자료기반 유입 수온 예측모델 개발 및 기후변화에 따른 대청호 성층강도 변화 예측", 환경영향평가, 30(5), pp.271~296 (2021), 한국환경영향평가학회
- Hodges B, "Aquatic ecosystem model: AEM3D v1.0 user manual", HydroNumerics, ~ (2019)
- Idso SB, "On the concept of lake stability", Limnol. Oceanogr, 18, pp.681~683 (1973)[DOI]
- Jeon BI, "A change of local meteorological environment according to dam construction of Nakdong-River: I. Meteorological data analysis before and after dam construction", Journal of the Environmental Sciences, 11(3), pp.161~168 (2002)
- 이상욱, "CE-QUAL-W2 모델을 이용한 임하호 선택배제시설의 효과분석", 한국물환경학회지, 23(2), pp.228~235 (2007), 한국물환경학회
- Lugg A, "Review of cold water pollution in the Murray & Darling Basin and the impacts on fish communities", Ecological Management & Restoration, 15(1), pp.71~79 (2014)
- Nürnberg GK, "Lake responses to long-term hypolimnetic withdrawal treatments", Lake and Reservoir Management, 23, pp.388~409 (2007)
- Olden JD, "Incorporating thermal regimes into environmental flows assessments : modifying dam operations to restore freshwater ecosystem integrity", Freshwater Biology, 55(1), pp.86~107 (2010)
- Pardo I, "Influence of dam operation on mayfly assemblage structure and life histories in two south-eastern Austrian streams", Regulated Rivers : Research & Management, 14, pp.285~295 (1998)
- Pujoni D, "Modeling vertical gradients in water columns: A parametric autoregressive approach", Limnol. Oceanogr. : Methods, pp.320~329 (2019)
- Preece RM, "The effect of Keepit Dam on the temperature regime of the Namoi River, Australia", River Research and Applications, 18(4), pp.397~414 (2002)
- Read JS, "Derivation of lake mixing and stratification indices from high-resolution lake buoy data", Environ. Model. Softw, 26, pp.1325~1336 (2011)[DOI]
- Rheinheimer DE, "Optimizing selective withdrawal from reservoirs to manage downstream temperatures with climate warming", J. Water Resour. Plann. Manage, 141(4), pp.04014063~ (2015)
- Status of cold water releases from Victorian Dams, "Ryan T", Victorian Department of Natural Resources and Environment, ~ (2001)
- Scoping Options for mitigating cold water discharges from dams, "Sherman B", CSIRO Land and Water, 1~47 (2000)
- Review of Temperature control options for reservoir release flows, "Svoboda C", U.S. Department of the Interior, Bureau of Reclamation, 1~22 (2020)
- Stevens LE, "Colorado River benthic ecology in Grand Canyon, Arizona, USA : dam, tributary and geomorphological influences", Regulated Rivers : Research and Management, 13, pp.129~149 (1997)
- Todd CR, "The impact of cold water releases on the critical period of post-spawning survival and its implications for Murray cod(Maccullochella peelii peelii) : a case study of the Mitta Mitta River, southeastern Australia", River Research and Applications, 21, pp.1035~1052 (2005)
- Ward JV, "Thermal characteristics of running waters", Hydrobiologia, 125, pp.31~46 (1985)
- Webb BW, "Trends in stream and river temperature", Hydrological Processes, 10, pp.205~226 (1996)
- "rLakeAnalyzer: Lake Physics Tools. R package version 1.11.4.1" (2018)[URL]
- Winton RS, "Reviews and syntheses : Dams, water quality and tropical reservoir stratification", Biogeosciences, 16(8), pp.1657~1671 (2019)