Cost allocation in complex water resource systems using a cooperative game theory approach

The interdisciplinary nature of water problems requires methods to integrates the technical, economic, environmental, social and legal aspects into a comprehensive framework that allows the development of efficient and sustainable water management strategies. The research presents a methodology for allocating costs among water users with a cooperative game theory approach based on the integral river basin modelling at monthly time detail. The proposed approach starts from the hydrologic and economic characterization of the system to be modelled. The hydraulic characterization of the basin includes the representation of surface hydrology by long monthly inflow time series, the application of continuity equations in the nodes and balance equations in the reservoirs and aquifers. The characterization of water costs is based on the determination of the construction and operation cost functions for hydraulic infrastructures and water uses. Decision support systems for water resources management (AquaTool, Andreu et al. 1996; WARGI, Sechi G.M. and Zuddas P., 2000) are used to simulate the water system performances and to calculate the characteristic function of each one of the user coalitions that may arise. The final cost allocation is calculated using the Shapley Value.