Facilitating cooperation among users in water conflicts with a tripartite evolutionary game model: A case study in the Hanjiang Basin, China

Water conflict is evolving into one of the most vital social and environmental issues as the global water crisis intensifies in recent years. Previous studies mostly focus on the game between water users but overlook the fact that water resource institutions (WRIs), which are increasingly involved in water conflicts, are also essential players. In this study, a tripartite evolutionary game model that considers WRIs, demand-side users, and supplyside users is developed. Seven potential evolutionary stable strategies and nine evolutionary scenarios are deduced. The theoretical findings are validated by simulating the water conflict of two provinces (i.e., Hubei and Henan) in the Hanjiang basin, China. The results indicate that non-cooperation among water users and ineffective intervention by WRIs are the long-term outcomes of this water conflict case. To foster cooperation, the game structure needs to be altered by affecting the external variables that determine the net benefits of excess water intake and water rights transfer. Owing to the insufficient long-term incentives for WRIs, cooperation among water users cannot rely on the intervention strategy. Nonetheless, even if external conditions are immature, the intervention strategy can act as auxiliary means to foster cooperation in advance but at the cost of some of the WRIs' interests. The outcomes of the present study can provide managers of water resources with contributing information for cooperation promoting among water users.