Comparison of Hedging Policies in Reservoir Management under Drought Condition

Tehran, with a population of about thirteen million has experienced severe municipal water shortages during past two decades. Under these circumstances, optimum use of available water resources through establishing certain policies considering priorities of various water demands seems inevitable. In this regard, hedging models can play an important role in proper utilization of water resources in Tehran especially during drought periods. The main objective of this research is to investigate the application of different types of hedging policies and the efficiency of some of the evolutionary algorithms in solving these policies. For this purpose, first comprehensive and integrated water resources systems operation models were established and then the application of different types of hedging policies using heuristic methods was carried out. In the next step, the efficiency of Harmony Search algorithms including the original method (HS) and an improved version called SGHS was evaluated in solving these problems. In this regard, the optimization of long-term multiple reservoir system operation was carried out using hedging rules and another case without any operation rule for comparison purposes. Finally, the results were compared with those of other methods including the space rule and the WEAP software.