The constantly increasing demand for a sufficient quantity and quality of water, properly distributed in time and space, has forced engineers and planners to contemplate and propose ever more comprehensive, complex and ambitious plans for water resource systems. Systems analysis methods can help identify plans or sets of plans that achieve to the greatest extent possible the goals and aims of those who plan, pay for and make use of water resource facilities and management plans. The application of systems methods such as simulation and optimization can significantly aid in the evaluation and selection of water resources investments, designs and policies. Optimization is a method to gain best answer in water resources plans. In this research, the estimation of regulated water volume in a multiple-basin region, including Zayanderood reservoir basin, and part of Kuhrang and cheshmelangan river basins has been studied. The water traortation projects from the two latest basins to the Zayanderood basin are either operation or under construction. Three reservoirs including Zayanderood, Kuhrang-3 and Sardab will regulate the water needs downstream of Zayanderood dam. The algorithm genetic method has been used to optimize the whole system. In this research, GA has been used to analyze reliabilities of proposed reservoirs and other facilities to supply future water needs, with basin hydrology represented by sequences of monthly natural streamflows and reservoir net evaporation-precipitation rates at all pertinent locations for a 45 years hydrologic period-of-analysis.
