Transboundary water management is complex with competing interests in different countries. When the Grand Ethiopian Renaissance Dam near the Ethiopian-Sudan border will be completed the Nile will have two of the world's largest dams, with the High Aswan Dam located downstream. While the dams could significantly change the river's flows, there is no specific agreement yet on the dams' reservoir operations. Nearly all of the consumptive water use takes place downstream in Sudan and Egypt, though 85% of the Nile's water originates in Ethiopia.
In a
study published in Nature Communications IWP's Adjunct Senior Research Fellow Dale Whittington and his co-authors analyse the impacts of the Grand Ethiopian Renaissance Dam during the filling process of the reservoir, during the 'new normal' situation after the reservoir is filled, and during multi-year drought. They find that during the filling the High Aswan Dam reservoir could fall to levels not seen in recent decades, although the risk of water shortage in Egypt is relatively low. The 'new normal' will benefit Ethiopia and Sudan without significantly affecting water users in Egypt. Management of multi-year droughts will require careful coordination if risks of harmful impacts are to be minimised.