Allocation and Management of Water Resources in the Yamchi Dam Basin with Scenario Analysis Approach Using WEAP Model

Background and Objective: Due to limited water resources and increasing water needs, the potentials of water resource allocation using the traditional methods are decreased and the use of new allocation strategies and managing water resources in choosing projects and making correct decisions in allocating and managing water resources is more important than ever.Method: Accordingly, Yamchi dam and its downstream areas are simulated in the WEAP model environment and the model is implemented for current conditions and future development projects in ten different scenarios. The proposed scenarios included examining the impact of allocation, industry needs, increasing irrigation efficiency, removing groundwater resources, changing cropping patterns, single cropping, and combined scenarios. The entries included information on the Yamchi dam and reservoir, groundwater resources, and the parameters needed to calculate the nodes for drinking, agricultural, industrial and environmental needs.Findings: The results showed that among the proposed scenarios for the areas under study, the scenario of simultaneous change of cropping pattern and 65% increase in irrigation efficiency is the most suitable option among the studied scenarios, which meets time and volume reliability of drinking and agricultural needs by 100% and will reduce the needs of the current situation by 44%.Discussion and Conclusion: It is worth noting that if the groundwater source is eliminated for any reason, none of the solutions of changing the cropping pattern, increasing efficiency, etc. can fulfill the shortage and it is necessary to treat urban, agricultural and industrial wastewaters and reuse one of them. The results show that urban wastewater treatment and reuse can provide about 60 percent of the shortage of groundwater resources.