Developing WEAP an integrated water resources model for modeling in drought conditions

One of the most important problems of water resources operation systems, specifically surface reservoirs in confronting hydrologic variability, is considering drought phenomenon effects on operation methods. As well as flow variations relative to average flow, duration of the drought is another important factor. One way to resist the drought is suitable operation of water resources during drought conditions. There are several models developed for water resources management such as WEAP software. But such models do not have water resources modeling capability during drought conditions. Therefore, developing such capability on WEAP model is highly important for water resources engineers. Developing the hedging rules for operation based on WEAP software was investigated by this research by which an extension program was developed in WEAP software. Developing such model would enable us to jointly optimize and simulate on basins. In order to test the capability of the complementary program, modeling was performed on operation of Gorganrood river reservoirs. Then the results of the developed model were compared to the ordinary WEAP software results. The results indicated 1 to 38 percent increased capability of WEAP software on modeling for hydrologic drought conditions. It is worth mentioning that the complementary model was developed as a general model by which the model can be used on different basins.