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2026 Vol.59, Issue 7S-1
Development and application of an index for monitoring environmental drought impact on water quality

수질에 대한 환경가뭄 모니터링을 위한 지수 개발 및 적용

Sangung Leea
,
Jaeyeon Limb
,
Bu Geon Joc
,
Young Do Kimd*
,
Joo-Heon Leee
이 상웅a
,
임 재연b
,
조 부건c
,
김 영도d*
,
이 주헌e
aPh.D. Student, Department of Civil and Environmental Engineering, Myongji University, Yongin, Korea
bJunior Researcher, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology, Goyang, Korea
cPostdoctoral Researcher, Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology, Goyang, Korea
dProfessor, Division of Smart Infrastructure Engineering, Myongji University, Yongin, Korea
eProfessor, Department of Civil Engineering, Joongbu University, Goyang, Korea
a명지대학교 토목환경공학과 박사과정
b한국건설기술연구원 수자원하천연구본부 신진연구원
c한국건설기술연구원 수자원하천연구본부 박사후연구원
d명지대학교 스마트인프라공학부 교수
e중부대학교 토목공학과 교수
*Corresponding Author
31 July 2026. pp. 761-772
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Abstract

Recent abnormal climate patterns have intensified droughts, increasing environmental risks to aquatic ecosystems. This study proposes an Environmental Drought Index for Water Quality (ED(WQ)I) to quantitatively assess drought-induced degradation in riverine systems. The index integrates real-time water quality parameters such as BOD, DO, and EC with hydrological indicators including streamflow, no-rain days, and cumulative rainfall. Using a regression-based weighted summation approach, the index was applied to ten major tributaries of the Nakdong River Basin. Results revealed that as drought severity increased, BOD exceedance rates rose across most basins. In highly impervious basins such as Hoe and Nam Rivers, water quality deteriorated persistently, regardless of flow conditions. In contrast, sharp degradation occurred only under extreme drought conditions in basins like Miryang and Yeong Rivers. To enable early detection, Euclidean distance-based thresholds were applied to identify season- and grade-specific predictive parameters. The proposed method achieved prediction accuracies of 80–100% in most basins. These findings highlight the necessity of water quality-based early warning systems that reflect basin-specific hydrological sensitivity and support the use of ED(WQ)I as a foundational tool for tailored drought response strategies.

Keywords
Environmental drought
Water shortage
Water quality management
Short-term forecast

최근 이상기후로 가뭄이 심화되며 수생태계에 환경적 위험이 증가하고 있다. 본 연구는 가뭄에 따른 수질 악화를 정량적으로 반영할 수 있는 환경가뭄(수질)지수를 개발하였다. BOD, DO, EC 등의 실시간 수질자료와 유량, 무강우일수, 누적강수량 등의 수문자료를 통합하여 가뭄의 환경학적 영향을 평가하며, 회귀기반 가중합 방식으로 산정되었다. 낙동강 수계 10개 주요 지류를 대상으로 분석한 결과, 가뭄 단계가 심화할수록 BOD 초과율이 증가하였고, 회천, 남강 등 불투수율이 높은 유역은 수질이 지속적으로 악화되었다. 반면, 밀양강과 영강 등 일부 유역은 극심한 가뭄에서만 급격한 수질 저하가 발생하였다. 조기 감지를 위해 유클리드 거리 기반 임계값을 활용하여 계절 및 등급별 주요 예측 인자를 도출하였으며, 대부분 유역에서 80~100%의 성능으로 예측되었다. 수문특성에 따른 가뭄 민감도 차이를 반영한 수질 기반 조기경보체계의 필요성을 제시하며, 환경가뭄(수질)는 맞춤형 대응 전략 마련의 기초자료로 활용될 것으로 판단된다.

키워드
환경가뭄
물부족
수질 관리
단기예보
References
1

Crausbay, S.D., Ramirez, A.R., Carter, S.L., Cross, M.S., Hall, K.R., Bathke, D.J., Betancourt, J.L., Colt, S., Cravens, A.E., Dalton, M.S., and Dunham, J.B., et al. (2017). “Defining ecological drought for the twenty-first century.” Bulletin of the American Meteorological Society, Vol. 98, No. 12, pp. 2543-2550.

10.1175/BAMS-D-16-0292.1
2

Eo, G., and Kim, H.S. (2025). “MODSIM-based study on water deficiency and management strategies in the Yeongsan- Seomjin River Basin.” Journal of the Korean Society of Hazard Mitigation, Vol. 25, No. 2, pp. 107-120.

10.9798/KOSHAM.2025.25.2.107
3

Gwak, Y., Cho, J., Jung, I., Kim, D., and Jang, S. (2018). “Projection of future changes in drought characteristics in Korea peninsula using effective drought index.” Journal of Climate Change Research, Vol. 9, No. 1, pp. 31-45.

10.15531/ksccr.2018.9.1.31
4

Han, H., Bai, J., Yan, J., Yang, H., and Ma, G. (2021). “A combined drought monitoring index based on multi-sensor remote sensing data and machine learning.” Geocarto International, Vol. 36, No. 10, pp. 1161-1177.

10.1080/10106049.2019.1633423
5

Hao, Z., Zhang, X., Pang, Y., Lv, B., and Singh, V.P. (2025). “Spatial- temporal monitoring of compound droughts over global land areas.” Environmental Modelling & Software, Vol. 189, 106463.

10.1016/j.envsoft.2025.106463
6

Jiang, J., Wang, Z., Zhang, Z., Wu, X., Lai, C., Zeng, Z., and Chen, X. (2025). “Extreme drought-heatwave exacerbates water quality deterioration in China.” Ecological Indicators, Vol. 170, 113008.

10.1016/j.ecolind.2024.113008
7

Jo, B.G., Jung, W.S., Nam, S.H., and Kim, Y.D. (2023). “Prediction of cyanobacteria using decision tree algorithm and sensor monitoring data.” Applied Sciences, Vol. 13, No. 22, 12266.

10.3390/app132212266
8

Jo, B.G., Lim, J., Lee, J.H., and Kim, Y.D. (2024). “Research on the index calculation method for the impact of drought on water quality in the Nakdong River, Korea.” Hydrology, Vol. 11, No. 11, 190.

10.3390/hydrology11110190
9

Kal, B.,Park, J., Kim, S., Shim, K., Shin, S., and Choi, S. (2022). “A study on evaluation of water quality measurement network in the Nakdong River tributary using TOPSIS.” Journal of Wetlands Research, Vol. 24, No. 1, pp. 44-51

10.17663/JWR.2022.24.1.44
10

Kılıç, V.N., and Eşsiz, E.S. (2025). “K-Salp Swarm Anomaly Detection (K-SAD): A novel clustering and threshold-based approach for cybersecurity applications.” Computers & Security, Vol. 151, 104325.

10.1016/j.cose.2025.104325
11

Kim, J.E. , Son, H.J., Kim, T., Kim, W.B., and Kim, T.W. (2024). “Investigation of drought propagation and damage characteristics using meteorological and hydrological drought indices.” Journal of Civil and Environmental Engineering Research, Vol. 44, No. 3, pp. 291-302.

10.12652/KSCE.2024.44.3.0291
12

Lee, C.W., Jung, D., Park, M.J., and Yoo, D.G. (2019). “Application of envelope curve method for quantitative definition of extreme drought conditions.” Journal of the Korean Society of Hazard Mitigation, Vol. 19, No. 5, pp. 245-251.

10.9798/KOSHAM.2019.19.5.245
13

Lee, J.H., and Kim, C.J. (2011). “Derivation of drought severity- duration-frequency curves using drought frequency analysis.” Journal of Korea Water Resources Association, Vol. 44, No. 11, pp. 889-902.

10.3741/JKWRA.2011.44.11.889
14

Lee, S., Jo, B., and Kim, Y.D. (2022). “Assessment of water quality index suitability of domestic watersheds.” Journal of Korea Water Resources Association, Vol. 55, No. 5, pp. 371-381.

10.3741/JKWRA.2022.55.5.371
15

Lee. S., Lee, T., and Lee, J.H. (2023). “Development of alarm grit ratio for drought forecasting and its application to the 2021- 2023 Drought.” Journal of the Korean Society of Hazard Mitigation, Vol. 23, No. 4, pp. 23-30.

10.9798/KOSHAM.2023.23.4.23
16

Lim, J., Lee, S., Jo, B., Do Kim, Y., and Lee, J.H. (2024). “Evaluation of environmental drought index applicability for watershed- specific drought management.” Journal of Korea Water Resources Association, Vol. 57, No. 10, pp. 699-709.

10.3741/JKWRA.2024.57.10.699
17

Liu, J., Zhu, Y., Horton, R., Lü, H., Ahmed, N., Fu, Y., Xu, Y., Chen, T. and Yao, Y. (2025). “Agricultural drought recovery characteristics and water requirement for rapid drought recovery in the Huai River Basin, China.” Journal of Hydrology: Regional Studies, Vol. 59, 102396.

10.1016/j.ejrh.2025.102396
18

Lloyd-Hughes, B. (2014). “The impracticality of a universal drought definition.” Theoretical and Applied Climatology, Vol. 117, pp. 607-611.

10.1007/s00704-013-1025-7
19

Ma, C., Song, M., Zeng, W., Wang, X., Chen, T., and Wu, S. (2025). “Enhancing urban emergency response: A euclidean distance- based framework for optimizing rescue facility layouts.” Sustainable Cities and Society, Vol. 118, 106006.

10.1016/j.scs.2024.106006
20

Mishra, A.K., and Singh, V.P. (2010). “A review of drought concepts.” Journal of Hydrology, Vol. 391, No. 1-2, pp. 202-216.

10.1016/j.jhydrol.2010.07.012
21

Mosley, L.M. (2015). “Drought impacts on the water quality of freshwater systems; review and integration.” Earth-Science Reviews, Vol. 140, pp. 203-214.

10.1016/j.earscirev.2014.11.010
22

Qin, H., Wang, Y., Ma, X., Wang, J., and Jiang, C. (2023). “A euclidean distance-based parameter reduction algorithm for interval- valued fuzzy soft sets.” Expert Systems with Applications, Vol. 234, 121106.

10.1016/j.eswa.2023.121106
23

Raposo, V.D.M.B., Costa, V.A.F., and Rodrigues, A.F. (2023). “A review of recent developments on drought characterization, propagation, and influential factors.” Science of the Total Environment, Vol. 898, 165550.

10.1016/j.scitotenv.2023.165550
24

Senapati, U., and Das, T.K. (2025). “Enhancing agricultural drought monitoring with the Integrated Agricultural Drought Index (IADI): A multi-source remote sensing approach.” Advances in Space Research, Vol. 75, No. 12, pp. 8599-8626.

10.1016/j.asr.2025.04.021
25

Seo, M., Cho, C., Im, T., Kim, S., Yoon, H., Kim, Y., and Kim, G. (2019a). “Statistical analysis of the spatio-temporal water quality characteristics of the Nakdong River.” Journal of Environmental Science International, Vol. 28, No. 3, pp. 303-320.

10.5322/JESI.2019.28.3.303
26

Seo, M., Lee, H., and Kim, Y. (2019b). “Relationship between coliform bacteria and water quality factors at weir stations in the Nakdong River, South Korea.” Water, Vol. 11, No. 6, 1171.

10.3390/w11061171
27

Van Huijgevoort, M.H., Hazenberg, P., Van Lanen, H.A., and Uijlenhoet, R. (2012). “A generic method for hydrological drought identification across different climate regions.” Hydrology and Earth System Sciences, Vol. 16, No. 8, pp. 2437-2451.

10.5194/hess-16-2437-2012
28

Van Loon, A.F. (2015). “Hydrological drought explained.” Wiley Interdisciplinary Reviews: Water, Vol. 2, No. 4, pp. 359-392.

10.1002/wat2.1085
29

Vicente-Serrano, S.M., Beguería, S., and López-Moreno, J.I. (2010). “A multiscalar drought index sensitive to global warming: the standardized precipitation evapotranspiration index.” Journal of climate, Vol. 23, No. 7, pp. 1696-1718.

10.1175/2009JCLI2909.1
30

Vicente-Serrano, S.M., Quiring, S.M., Peña-Gallardo, M., Yuan, S., and Domínguez-Castro, F. (2020). “A review of environmental droughts: Increased risk under global warming?.” Earth- Science Reviews, Vol. 201, 102953.

10.1016/j.earscirev.2019.102953
31

Xiang, K., Wang, B., Li Liu, D., Chen, C., Waters, C., Huete, A., and Yu, Q. (2023). “Probabilistic assessment of drought impacts on wheat yield in south-eastern Australia.” Agricultural Water Management, Vol. 284, 108359.

10.1016/j.agwat.2023.108359
32

Xu, C., Xu, C., and Li, G. (2025). “Establishment and validation of a novel composite index for energy efficiency evaluation of data center chilled water systems based on AHP and Entropy Weight Method.” Energy and Buildings, Vol. 337, 115677.

10.1016/j.enbuild.2025.115677
33

Yang, C., Liu, C., Xing, X., and Ma, X. (2025). “Predicting the risk and trigger thresholds for propagation of meteorological droughts to agricultural droughts in China based on Copula- Bayesian model.” Agricultural Water Management, Vol. 313, 109468.

10.1016/j.agwat.2025.109468
34

Zeybekoglu, U. (2025). “Comparative drought analysis in Amasya and Merzifon with ZSI, PNI and NDI under transitional climatic conditions.” Dynamics of Atmospheres and Oceans, Vol. 110, 101556.

10.1016/j.dynatmoce.2025.101556
35

Zhang, K., Li, Z. L., Shi, W. Z., Tao, R., Yang, X., and Huang, Y.M. (2025). “Spatiotemporal changes and interconnections between meteorological and hydrological droughts in China over past 34 years.” Water Science and Engineering, Vol. 18, No. 3, pp. 274-287.

10.1016/j.wse.2025.04.007
36

Zhang, X., Hao, Z., Singh, V.P., Zhang, Y., Feng, S., Xu, Y., and Hao, F. (2022). “Drought propagation under global warming: Characteristics, approaches, processes, and controlling factors.” Science of the Total Environment, Vol. 838, 156021.

10.1016/j.scitotenv.2022.156021
37

Zink, M., Samaniego, L., Kumar, R., Thober, S., Mai, J., Schäfer, D., and Marx, A. (2016). “The German drought monitor.” Environmental Research Letters, Vol. 11, No. 7, 074002.

10.1088/1748-9326/11/7/074002
Information
  • Publisher :KOREA WATER RESOURECES ASSOCIATION
  • Publisher(Ko) :한국수자원학회
  • Journal Title :Journal of Korea Water Resources Association
  • Journal Title(Ko) :한국수자원학회 논문집
  • Volume : 59
  • No :7
  • Pages :761-772
  • Received Date : 2025-05-09
  • Revised Date : 2025-08-25
  • Accepted Date : 2025-09-05
  • DOI :https://doi.org/10.3741/JKWRA.2026.59.S-1.761
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