Application of a Coordination Model for a Large Number of Stakeholders with a New Game Theory Model

Water allocation is an important issue for systems with multiple stakeholders. Individual and collective decisions are very important for such systems. Thus, a new integrated game model is proposed to create a good balance between cooperative and non-cooperative strategies. A dam-aquifer system was selected for the case study in Iraq. The system referred to should supply different stakeholders with water requirements. Three game models are used: 1) cooperative theory, non-cooperative theory, new integrated game structure. Effective factors in the way of cooperation was considered to demonstrate variations in the allocation of water to the stakeholders. The results of the cooperative or centralized model were considered as the best results. The results indicated that the new game model had good agreement with the centralized model. The outputs indicated that the allocation share of the downstream coalition could increase 4, 5 and 7% for high, medium and low inflow, respectively when the allocation share of the upstream coalition decreased 5%, 6% and 5% for high, medium and low inflow, respectively. The inflow excess volume at 90%, 50%, and 10% are considered as low inflow, medium inflow, and high inflow, respectively. It has been observed that the allocated volume of water to coalition downstream is increased by decreasing the more allocated volume of water to the coalition upstream. In addition, the new model supported the individual profits by applying the rationality decision while the cooperative game did not consider the individual benefits. In addition, the effect of inflows to reservoirs was considered to investigate the issue of water allocation in a critical condition.