Evaluation of Environmental Flows in the Ajichay River Using Eco-Hydrological Methods

Authors

1 water eng. dep.

2 4- Assistant professor of water engineering, Urmia University

Abstract

Development of water resources projects are accompanied by several environmental impacts, among them, the changes in the natural flow regime and the reduction of downstream water flows. The assessment of environmental flow requirements in a river eco-system is a challenging practice. Ajichay River is the most important river of Urmia Lakes Basin, Providing 10% of entrance surface water flow to the lake. Therefore, Provision of environmental water requirements of this river is to be an important task. The main aim of the present study was to use different Eco-hydrologic methods to determine the environmental flow requirements in a typical perennial river, the Ajichay River. The overall results indicate that the FDC Shifting method is well adapted to the river condition. In order to maintain the Ajichay River at minimum acceptable environmental status (i.e. Class C of the River environmental management), an average annual flow of 1.52 m3/s is to be allocated along the river in the Akhula Station, located 70 km upstream from the Urmia Lake.

Keywords