Assessment of environmental flows under limited data availability – Case study of the Acheloos River, Greece

A. Efstratiadis, A. Tegos, A. Varveris, and D. Koutsoyiannis, Assessment of environmental flows under limited data availability – Case study of the Acheloos River, Greece, Hydrological Sciences Journal, 59 (3-4), 731–750, doi:10.1080/02626667.2013.804625, 2014.



The lower course of Acheloos River is an important hydrosystem of Greece, heavily modified by a cascade of four hydropower dams, which is now being extended by two more dams in the upper course. The design of the dams and hydropower facilities that are in operation has not considered any environmental criteria. However, in the last fifty years, numerous methodologies have been proposed to assess the negative impacts of such projects to both the abiotic and biotic environment, and to provide decision support towards establishing appropriate constraints on their operation, typically in terms of minimum flow requirements. In this study, seeking for a more environmental-friendly operation of the hydrosystem, we investigate the outflow policy from the most downstream dam, examining alternative environmental flow approaches. Accounting for data limitations, we recommend the Basic Flow Method, which is parsimonious and suitable for Mediterranean rivers, whose flows exhibit strong variability across seasons. We also show that the wetted perimeter – discharge method, which is an elementary hydraulic approach, provides consistent results, even without using any flow data. Finally, we examine the adaptation of the proposed flow policy (including artificial flooding) to the real-time hydropower generation schedule, and the management of the resulting conflicts.

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Our works referenced by this work:

1. D. Koutsoyiannis, A. Efstratiadis, and G. Karavokiros, A decision support tool for the management of multi-reservoir systems, Journal of the American Water Resources Association, 38 (4), 945–958, doi:10.1111/j.1752-1688.2002.tb05536.x, 2002.
2. A. Christofides, A. Efstratiadis, D. Koutsoyiannis, G.-F. Sargentis, and K. Hadjibiros, Resolving conflicting objectives in the management of the Plastiras Lake: can we quantify beauty?, Hydrology and Earth System Sciences, 9 (5), 507–515, doi:10.5194/hess-9-507-2005, 2005.
3. A. Varveris, P. Panagopoulos, K. Triantafillou, A. Tegos, A. Efstratiadis, N. Mamassis, and D. Koutsoyiannis, Assessment of environmental flows of Acheloos Delta, European Geosciences Union General Assembly 2010, Geophysical Research Abstracts, Vol. 12, Vienna, 12046, doi:10.13140/RG.2.2.14849.66404, European Geosciences Union, 2010.
4. D. Koutsoyiannis, Scale of water resources development and sustainability: Small is beautiful, large is great, Hydrological Sciences Journal, 56 (4), 553–575, doi:10.1080/02626667.2011.579076, 2011.
5. A. Efstratiadis, and K. Hadjibiros, Can an environment-friendly management policy improve the overall performance of an artificial lake? Analysis of a multipurpose dam in Greece, Environmental Science and Policy, 14 (8), 1151–1162, doi:10.1016/j.envsci.2011.06.001, 2011.
6. D. Koutsoyiannis, N. Mamassis, A. Efstratiadis, N. Zarkadoulas, and Y. Markonis, Floods in Greece, Changes of Flood Risk in Europe, edited by Z. W. Kundzewicz, Chapter 12, 238–256, IAHS Press, Wallingford – International Association of Hydrological Sciences, 2012.
7. D. Koutsoyiannis, Water control in the Greek cities (solicited), Water systems and urbanization in Africa and beyond, Uppsala, Sweden, doi:10.13140/RG.2.2.36217.67680, 2012.

Our works that reference this work:

1. H. Tyralis, A. Tegos, A. Delichatsiou, N. Mamassis, and D. Koutsoyiannis, A perpetually interrupted interbasin water transfer as a modern Greek drama: Assessing the Acheloos to Pinios interbasin water transfer in the context of integrated water resources management, Open Water Journal, 4 (1), 113–128, 12, 2017.
2. A. Tegos, W. Schlüter, N. Gibbons, Y. Katselis, and A. Efstratiadis, Assessment of environmental flows from complexity to parsimony - Lessons from Lesotho, Water, 10 (10), 1293, doi:10.3390/w10101293, 2018.

Works that cite this document: View on Google Scholar or ResearchGate

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1. Acreman, M. C., I. C. Overton, J. King, P. Wood, I. G. Cowx, M. J. Dunbar, E. Kendy, and W. Young, The changing role of ecohydrological science in guiding environmental flows, Hydrological Sciences Journal, 59(3–4), 1–18, 2014.
2. #Egüen, M., M. J. Polo, Z. Gulliver, E. Contreras, C. Aguilar, and M. A. Losada, Flood risk trends in coastal watersheds in South Spain: direct and indirect impact of river regulation, Changes in Flood Risk and Perception in Catchments and Cities, Proc. IAHS, 370, 51-56, doi:10.5194/piahs-370-51-2015, 2015.
3. Aguilar, C., and M. J. Polo, Assessing minimum environmental flows in nonpermanent rivers: The choice of thresholds, Environmental Modelling and Software, 79, 120-134, doi:10.1016/j.envsoft.2016.02.003, 2016.
4. Nerantzaki, S. D., G. V. Giannakis, N. P. Nikolaidis, I. Zacharias, G. P. Karatzas, and I. A. Sibetheros, Assessing the impact of climate change on sediment loads in a large Mediterranean watershed, Soil Science, 181(7), 306-314, 2016.
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6. Tegos, M., I. Nalbantis, and A. Tegos, Environmental flow assessment through integrated approaches, European Water, 60, 167-173, 2017.
7. Gemitzi, A., and V. Lakshmi, Evaluating renewable groundwater stress with GRACE data in Greece, Groundwater, 56(3), 501-514, doi:10.1111/gwat.12591, 2018.
8. Theodoropoulos, C., N. Skoulikidis, P. Rutschmann, and A. Stamou, Ecosystem-based environmental flow assessment in a Greek regulated river with the use of 2D hydrodynamic habitat modelling, River Research and Applications, 34(6), 538-547, doi:10.1002/rra.3284, 2018.
9. Zhao, C., S. Yang, J. Liu, C. Liu, F. Hao, Z. Wang, H. Zhang, J. Song, S. M. Mitrovic, and R. P. Lim, Linking fish tolerance to water quality criteria for the assessment of environmental flows: A practical method for streamflow regulation and pollution control, Water Research, 141, 96-108, doi:10.1016/j.watres.2018.05.025, 2018.
10. Operacz, A., A. Wałęga, A. Cupak, and B. Tomaszewska, The comparison of environmental flow assessment - The barrier for investment in Poland or river protection? Journal of Cleaner Production, doi:10.1016/j.jclepro.2018.05.098, 2018.

Tagged under: Course bibliography: Water Resources Management, Environment, Hydrosystems