Assessment of Environmental Water Requirement Allocation in Anthropogenic Rivers with a Hydropower Dam Using Hydrologically Based Methods—Case Study

Anthropogenic activities such as damming have caused an alteration in the natural flow regime many rivers around world. In this study, role of constructing a hydroelectric dam on Kor River, Iran, is investigated. Nine different methods, which fall into category hydrological were used to determine environmental water requirement (EWR) River. addition, two indices are introduced evaluate allocation anthropogenic rivers. The results show that although supply some months relatively acceptable conditions average, there deficiency EWR range 1.92–30.2% spawning period dominant fish species. proposed indicators can provide general picture status where little ecological data available and has changed due human activities, particularly with hydropower plants. Moreover, after construction dam, no major floods occurred river, led loss morpho-ecological balance river disruption state habitats. Therefore, negative impact should be considered active management outlets.