Finding the Causes and Evaluating Their Impacts on Urmia Lake Crisis ‎Using a Comprehensive Water Resources Simulation Model

Abstract

Urmia Lake in northwestern Iran has been facing critical water level shrinkage in recent years with ‎serious environmental consequences. It is expected that with the current trend, the lake will be ‎completely dried out in a few years from now. This study attempts to assess the impacts of human ‎activities on water level fluctuations of Urmia Lake by developing a comprehensive hydrologic ‎simulation model. Model development and calibration was carefully accomplished by utilizing effective ‎water resources management components in the basin. An important contribution was accomplished by ‎properly estimating the agricultural water demand and consumption in the absence of measured data. ‎Result of long-term simulation reveals that excessive water consumption by inefficient and expanding ‎irrigated agriculture is the main reason for Urmia Lake shrinkage. It was found that main reservoirs are ‎only responsible for 23% of current situation. Whereas, 77% of the current crisis has been caused by ‎miscellaneous agricultural water withdrawals in the basin.‎