Evaluation of Water Management Scenarios for the Rio Grande/Bravo

Due to the scarcity of the water resources in the Rio Grande/Bravo basin, alternative water management policies or "Scenarios" have been evaluated to determine their hydrologic feasibility and the individual or joint benefits to water users in the basin. The policies evaluated are proposals of stakeholders, local water management agencies, technicians, and experts in Mexico and the United States. Scenarios include water rights buybacks, groundwater banking through in lieu recharge, allocation of non-treaty tributary flows toward treaty delivery obligations, and allocation of water savings from agricultural water conservation. For example, the in lieu groundwater banking method is defined by the surface water available in the basin. If there is enough surface water available, recharge is accomplished by curtailing groundwater pumping and providing surface water to water users. On the other hand, if there is not enough surface water, groundwater and surface water are used to meet the water demands. The evaluation model has been constructed in the Water Evaluation and Planning system (WEAP). Various hydrological conditions, such as normal, wet or dry, have been defined to compare the performance of the proposed policies with the current water management policies under different hydrological conditions. The scenarios and their evaluation are presented along with a comparison against the current water management policies.