Evaluation of different water allocation scenarios from Kalan Malayer Reservoir using MODSIM software

Due to increasing gap between water supply and demand, paying close attention to the principles of optimal water allocation is inevitable. In the present investigation, allocations from Kalan Malayer Reservoir to demands identified by the Iranian Ministry of Energy were evaluated using MODSIM8.1. These demands are environmental and sustainability requirements, City of Malayer drinking water, agricultural requirement of the downstream lands, irrigation of Sahand Malayer farms and industrial centers. The analysis temporal scale was a 12-month period with monthly time steps during year 2016-2017. The purpose of this study was to evaluate the behavior of the dam reservoir when the inflow is reduced. Four scenarios including 5, 10, 15 and 20 percent river reduction in flow to the reservoir were investigated. The results indicated that with decrease in the river inflow, the stored water in the dam reservoir would decreased and there would be shortage to meet all demands. The deficiencies volume in supplying water to demands from the first scenario to the fourth scenario was 0.373, 0.748, 1.124 and 1.508 MCM, respectively. In other words, the relationship between the decrease in stored water volume in the dam reservoir and river inflow reduction was linear. Therefore, in order to meet the demands in all four scenarios, the allocation to the demand points should be reduced according to the priorities of the demands. The other solution is to reduce the target storage volume equal to the total deficiency volume in that month.