Document Type : Research Article
Authors
1 Department of Water Engineering, Urmia University
2 Department of Water Eng. Urmia University
3 Associate Professor of Water Engineering Department, Urmia University Urmia - IRAN.
Abstract
This study aimed to estimate the minimum environmental flow (EF) of the Mahabad-Chay River, located south of Lake Urmia. The research focused on two main tributaries, Bytas and Koter, as well as the mainstream Gerd-Yaghub. The EF demand for the river was assessed and compared using five hydrological methods, leading to the selection of the most appropriate method. The minimum EF requirements were estimated to be 0.35 m³/s for Bytas, 1.17 m³/s for Koter, and 1.15 m³/s for Gerd-Yaghub. Additionally, the annual average flows were recorded as 1.73 m³/s, 6.17 m³/s, and 4.42 m³/s at the Bytas, Koter, and Gerd-Yaghub hydrometric stations, respectively. Based on these results, the Flow Duration Curve (FDC) shifting method at class C was recommended as the best approach for estimating the minimum EF for the Mahabad-Chay River due to its requirement for fewer data and its ability to rapidly analyze accessible data compared to other methods.
Keywords
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