Seasonal assessment of eutrophication potential and thermal stratification in Esteghlal reservoir

Document Type : Research Paper

Author

Department of Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

10.22059/jwim.2024.365447.1105

Abstract

This study investigates the water quality dynamics of Esteghlal Reservoir over a five-year period, with a specific emphasis on evaluating its eutrophication potential. We employed a two-dimensional water quality model, CE-QUAL-W2, to simulate daily variations in key variables, including temperature, dissolved oxygen, algae, phosphate, ammonia, and nitrate, which influence nutrient conditions and eutrophication. Due to significant fluctuations in the reservoir's water volume, water quality analysis was conducted seasonally. The results reveal a complex dynamic pattern within the nutrient cycle in the reservoir. In spring and summer, temperatures vary throughout the water column, indicating strong thermal stratification. There is a notable difference in dissolved oxygen concentration between the epilimnion and hypolimnion due to factors such as oxygen consumption by algae, limited wind-induced mixing, thermal stratification, and an extended detention time. In autumn, a reduction in inflow during the summer and evaporation lead to a decrease in water volume. This, along with a reduction in temperature, weakens thermal stratification. With the influx of floods in winter, water volume increases, and complete mixing occurs due to cooling. This provides a suitable environment to improve dissolved oxygen levels. However, it also leads to an increase in nutrient input. Simulation results and an assessment of nutrient criteria underscore the presence of eutrophication potential in most months. A well-defined monitoring program with optimized sampling frequency and location, coupled with the control of nutrient input through watershed management and detention time adjustment, can be considered effective strategies for improving the reservoir's condition.

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Main Subjects


  1. Abdolabadi, H., Sarang, A., Ardestani, M., & Mahjoobi, E. (2016). Eutrophication modeling using variable chlorophyll approach.
  2. Aghasian, K., Moridi, A., Mirbagheri, A., & Abbaspour, M. (2019). Selective withdrawal optimization in a multipurpose water use reservoir. International Journal of Environmental Science and Technology, 16, 5559-5568.
  3. Beiramipoor, S., Qaderi, K., Haghjuie, H., & Rahimpour, M. (2018). Reservoir water quality management of Baft dam through selected drainage from the dam outlet locations using the model CE-QUAL-W2. Irrigation and Water Engineering, 8(3), 237-251. (in Persian).
  4. Borah, D. K., Knapp, H. V., Raman, R. K., Lin, S. D., & Soong, T. D. (1999). HEC-5Q model applied to a lake system in Illinois for water quality evaluations. Water international, 24(3), 240-247.
  5. Chapra, S. C. (2008). Surface water-quality modeling: Waveland press.
  6. Colarusso, L. A., Chermak, J. A., Priscu, J., & Miller, F. (2003). Modeling pit lake water column stability using Ce-Qual-W2. Paper presented at the Tailings and mine waste.
  7. Cole, T. M., & Wells, S. A. (2006). CE-QUAL-W2: A two-dimensional, laterally averaged, hydrodynamic and water quality model, version 3.5.
  8. Debele, B., Srinivasan, R., & Parlange, J.-Y. (2008). Coupling upland watershed and downstream waterbody hydrodynamic and water quality models (SWAT and CE-QUAL-W2) for better water resources management in complex river basins. Environmental Modeling & Assessment, 13, 135-153.
  9. Grey, D., & Sadoff, C. W. (2007). Sink or swim? Water security for growth and development. Water policy, 9(6), 545-571.
  10. Jiang, D. (2012). Temporal and spatial variation of thermal structure in Three Gorges Reservoir: a simulation approach. Journal of Food, Agriculture & Environment, 10(2 part 3), 1174-1178.
  11. Jozi, S. A., Hosseini, L., & Dehghani, A. (2016). Study of Environmental Impact of Minab Esteghlal Dam in Operation Phase Using a Combination of Modified and ICOLD Methods. Journal of Environmental Science and Technology, 18(3), 129-141. (in Persian).
  12. Khalaf, A., & Noshadi, M. (2018). Analysis of thermal stratification of Droodzen dam reservoir using CE-QUAL-W2 model. 11th National Congress of Civil Engineering, Shiraz.
  13. Kuo, J.-T., Lung, W.-S., Yang, C.-P., Liu, W.-C., Yang, M.-D., & Tang, T.-S. (2006). Eutrophication modelling of reservoirs in Taiwan. Environmental Modelling & Software, 21(6), 829-844.
  14. Larabi, S., Schnorbus, M. A., & Zwiers, F. (2022). A coupled streamflow and water temperature (VIC-RBM-CE-QUAL-W2) model for the Nechako Reservoir. Journal of Hydrology: Regional Studies, 44, 101237.
  15. Liang, D., Testa, J. M., Harris, L. A., & Boynton, W. R. (2023). A hydrodynamic model–based approach to assess sampling approaches for dissolved oxygen criteria in the Chesapeake Bay. Environmental Monitoring and Assessment, 195.
  16. Liu, W.-C., Chen, W.-B., & Kimura, N. (2009). Impact of phosphorus load reduction on water quality in a stratified reservoir-eutrophication modeling study. Environmental Monitoring and Assessment, 159, 393-406.
  17. Manatunge, J., Nakayama, M., & Priyadarshana, T. (2008). Environmental and social impacts of reservoirs: issues and mitigation. Oceans and aquatic ecosystems, 1, 212-255.
  18. Moridi, M., Sobra, A. R., Jafarzadeh, N., Amiri, F., & Koh Gardi, I. (2023). Investigation of thermal layering phenomenon of Minab dam using Ce-qual-w2 model and its effect on water quality in Bandar Abbas. Wetland Ecobiology, 14(1), 49-70. (in Persian).
  19. Nazariha, M., Danaei, E., Hashemi, S. H., & Izad Doustdar, A. H. (2010). Prediction of Thermal Stratification in Proposed Bakhtyari Reservoir With CE-QUAL-W2. Journal of Environmental Studies, 36(54). (in Persian).
  20. Nori -najafi, F., Veisi, H., Khoshbakhat, K., & Mirzaei-Talar Poshti, R. (2019). Assessing the Impacts of Dams on the Local Community and Environment in Iran: Systematic Review. Journal of Water and Sustainable Development, 5(2), 141-152. doi:10.22067/jwsd.v5i2.67
  21. Reichert, P., Borchardt, D., Henze, M., Rauch, W., Shanahan, P., Somlyody, L., & Vanrolleghem, P. A. (2001). River water quality model: IWA publishing.
  22. Rezaei Barandagh, H., Salmasi, F., & Sahebi, F. (2018). Water Quality and Temperature Stratification of Zanjan Taham Dam with CE-QUAL-W2 Software. Journal of Water and Soil Conservation, 25(1), 127-145. doi:10.22069/jwsc.2018.13327.2799. (in Persian).
  23. Saadatpour, M. (2020). An adaptive surrogate assisted CE-QUAL-W2 model embedded in hybrid NSGA-II_ AMOSA algorithm for reservoir water quality and quantity management. Water Resources Management, 34(4), 1437-1451.
  24. Salehi, M., Khani Temeliyeh, Z., Parchami, N., & Ahmadpour, Z. (2019). Numerical Modeling Of Thermal Stratification And Water Quality In Reservoir By CE-QUAL-W2 Model. Journal of Water and Soil Conservation, 26(4), 53-73. doi:10.22069/jwsc.2019.14971.3010. (in Persian).
  25. Shabani, N., Rahmanifiroozjaee, A., & Abessi, O. (2019). Thermal Stratification of Seymareh Dam Using Two-Dimensional, Hydrodynamic and Water Quality Model: CE-QUAL-W2. Journal of Environmental Science and Technology, 21(7), 77-87. doi:10.22034/jest.2018.22904.3200
  26. Shahraki Mojahid, R., Noshadi, M., & Alizadeh, A. (2014). Investigation and simulation of thermal stratification and salinity in Minab Esteghlal dam by HEC-5Q model. Paper presented at the National Congress of Irrigation and Drainage of Iran, Ahwaz. (in Persian).
  27. Sharma, D., & Kansal, A. (2013). Assessment of river quality models: a review. Reviews in Environmental Science and Bio/Technology, 12, 285.
  28. Shi, H., Chen, J., Liu, S., & Sivakumar, B. (2019). The role of large dams in promoting economic development under the pressure of population growth. Sustainability, 11(10), 2965.
  29. Talakesh, S., Fatahi Nafechi, R., Samadi Boroujeni, H., Mirabbasi Najafabadi, R., & Khajepour, I. (2019). Investigation on Stratification of Temperature and Dissolved Oxygen in a Large Dam Reservoir (Case study: Karun 3 Dam). Iranian Water Researches Journal, 13(1), 49-57. (in Persian).