Determination of the Optimal River Basin-Wide Agricultural Water Demand Quantities Meeting Satisfactory Reliability Levels

Abstract

The unbridled increase in water demands and beyond-sustainable water withdrawals have led to decrease reliable supply levels, particularly for agricultural purposes in Iran. Reallocation of water resource in basins and quantification of the optimal agricultural water demands to achieve a desirable reliability is essential. As a result, sustainability of water resources could be guaranteed during the current water scarcity. Optimum water resources allocation through quantification of the agricultural demands in the Atrak River Basin in Iran is investigated in this research by combining the MODSIM simulation engine and the Particle Swarm Optimization (PSO) algorithm provided that the desirable reliability criteria are satisfied. The objective function is defined as the maximization of the Nash bargaining function in the first scenario and maximization of the total water supply with consideration of the reliability constraints in the second scenario while the decision variables are the agricultural demand quantities across the basin. The results revealed that the agricultural demands in the basin should be reduced more than 50% to achieve the desirable reliability levels for water supply.