Multi-Objective Programming for the Allocation of Trans-Boundary Water Resources - the Case of the Euphrates and Tigris

The allocation of water in a multi-country river system necessarily involves conflicting objectives, where increasing water benefits to one country may entail losses to other countries. This paper presents the formulation and application of a multi-objective linear programming model, where each objective represents the benefits to a country from using water for agricultural, municipal, and energy uses, net of conveyance costs. This model extends the Euphrates and Tigris River Basin Model (ETRBM), presented in Kucukmehmetoglu and Guldmann (2004), with the three objective functions representing the net water benefits to the three riparian countries – Turkey, Syria, and Iraq. The model is used to delineate the set of non-inferior solutions (Pareto frontiers), where no individual country benefit can be increased without reducing the benefits of at least another country. These Pareto frontiers, and the underlying water resources allocations, are graphically displayed and analyzed under different scenarios related to river flow, electricity price, and agricultural productivity. The trade-offs between the three benefits are assessed, providing the basis for possible compromises among the three countries. Potential policy implications for trans-boundary water resources utilization are discussed.