A Decision Support System for Water Allocation in Water Scarce Basins

Nowadays, water supply is one of the main causes of tension for scientists in arid countries. Therefore, the assessment of water resources can be considered as a main challenge for the authorities around the world. Successful dicision making in water resources management tries to resolve competing and conflicting needs of water users from different sectors including: domestic, agriculture and industry. In this research, a systematic framework for assessing different scenarios in the system, has been defined based on WEAP. The proposed model was used in the Urmia Lake basin as a case study; A scenario, proposed by the Urmia Lake Reconstruction Team, presists on transmission of water to the lake. In this study, this scenario and some others, proposed by the Urmia Lake Reconstruction Team, were used in this model and the best scenario was identified using a decision support tool based on the principles of TOPSIS, which has been written in FORTRAN. In the following section, water allocation in the catchment was investigated based on the principles of game theory and the outcome of this research shows that applying game theory and using full cooperation games (based on the Shapley Values method), provides better outcomes for all competing users of water. In other words, using the notion of coalition between different sectors including domestic, agriculture and industry, can save about 332 MCM of water which can be used in the dying lake.