Mohamad Reza Madadi

The minimum flow which is needed for preserving the life of various species of aquatic animals and plants is named as environmental flow. Up to now, more than 200 different methods were presented for estimating the river environmental flow, that can be classified into 4 major groups of hydroogical methods, hydraulic methods, habitat simulation methods and holistic method. In this research, two hydrological methods of Tennant and flow duration curve (FDC) were used for estimating the environmental flow at Halil river in Kerman. To this purpose, using river flow data, the environmental flow was determined as a percentage of average annual river flow. The comparison of results of two methods indicated that the FDC method presents more reasonable estimation of environmental flow at this case study.