A Heuristic Evolutionary Game Theoretic Methodology for Conjunctive Use of Surface and Groundwater Resources

In this paper, a methodology based on a new heuristic evolutionary game is developed to determine evolutionary stable equilibrium (ESE) strategies for conjunctive surface and groundwater allocation to water users with conflicting objectives. The methodology provides reasonable and realistic framework to illuminate non-cooperative behaviors of water users in the joint usage of surface and groundwater resources. The developed heuristic evolutionary game theoretic approach can be used for finding equilibrium in asymmetric n-person games with continuous strategies. The penalty function is provided in a way that it can control groundwater table drawdown at monitoring points. It is also shown that applying the proposed penalty function may inhibit the water users’ excessive exploitation and can consequently avoid the tragedy of commons. As the methodology needs to run water allocation optimization and groundwater simulation models for several times, an optimization model based on genetic algorithms is linked with MODFLOW groundwater simulation model. Furthermore, a computational cost reduction method has been used to reduce the computation time caused by several consecutive computational steps in the proposed methodology. A pistachio loss function due to the deficit irrigation is also developed and used for evaluating water users’ objective functions. To illustrate the practical utility of the methodology, it is applied to the Rafsanjan plain in Iran and it is shown that this approach can be used for developing surface and groundwater allocation policies.