Modelled observations on Development scenarios in the lower Mekong Basin

The World Bank is in the process of developing a Mekong Regional Water Resources Assistance Strategy that will set out the scope for potential assistance to both regional and national projects in the basin over the next 10 years. A comprehensive Decision Support System is under development. The hydrological component is already in place, and has been calibrated, tested, approved and adopted by the Mekong River Commission (MRC). It comprises a suite of models that make it possible to simulate major hydrological aspects of river basin behaviour, which can in turn support and inform the negotiations that are now addressing the water-sharing issues. The MRC models have the capacity to test and evaluate development scenarios defined generically in terms of hydropower development, irrigation development and inter-basin diversions. The output of the models is quite narrowly hydrological - water utilised for irrigation and power generation; river flow and stage at key locations; volumes; inundated areas, depths and duration of inundation; and salinity levels. These parameters can in turn provide insights into possible impacts on fisheries, flood management, saline intrusion, navigation, and the environment.