Planning Water Resources Allocation under Various Managerial Scenarios in Gorganroud Basin

Integrated water resources management is very important due to rapid population growth and limitation of water resources. There are different models for optimum water resources planning and management in a watershed area. In recent years the WEAP model has been used by many researchers due to its ability to consider the coupled physical-hydrological processes and the integrated water resources management systems as well as to prioritize water allocation. The main objective of this study was to use WEAP model for determining the amount of water allocated to industry from the Voshmgir and Golestan dams in the Gorganroud Basin (Golestan province). Thus, at first, the Gorganroud basin monthly flow was simulated and then the model was run for existing conditions and different scenarios. For this purpose, the “water year method” option in WEAP was used. In this model, sedimentation volume in reservoirs was incorporated by a cumulative manner as a dead storage at the end of each month. After modeling the Gorganroud basin with WEAP model, the allocated water volume percentages for agricultural, industrial, aquatic and environmental demands, considering the aims of project were obtained. The results showed that with the new allocation planning of the Gorganroud water resources, the water demand of the industry around the Voshmgir dam would be supplied up to 9.5 million cubic meters, accepting a 5% reduction in the system reliability. By ignoring reservoir sedimentation in modeling process, the system reliability reduced significantly. Moreover, considering 1 million cubic meters reduction in reservoir volume due to sedimentation every 5 years and increase of irrigation efficiencies, can preserve the system reliability in planning.