Development of Sustainable Water Supply Scheme in Reservoir Operation: Case Study

The development of societies is dependent upon the sustainable water supply through sound management of resources. It is important to determine the sustainable capacity of the water resources if further development is needed. Reservoirs play an important role in water supply of basins in arid and semi-arid regions. In this paper a methodology is proposed to find a sustainable water supply scheme in reservoir operation considering the impacts of climate change on inflow and water demand variations. Different approaches such as deterministic and chance constraint optimization models are utilized for this purpose in both monthly and annual time scales. The objective function of the optimization model is to maximize the minimum reservoir release. As extreme dry or wet years can highly affect the model results, their effects on the reliable water supply are also evaluated. The proposed method has been applied to the Sattarkhan Reservoir located in Ahar-chay basin in northwest Iran. Through the probabilistic approach, the reservoir operation can be managed with different risk levels and potential hazards. The results show that the reservoir has been overdesigned and it could carry only 60% of its capacity. Furthermore, the potential water resources in the studied basin are decreasing.