Good for Ethiopia, good for Egypt
CRISIS averted? Scientists may be on the verge of resolving a potentially war-triggering water dispute: how to share out the flow of the River Nile. A decades-long row over one of the world\’s longest rivers pits downstream Egypt, whose agriculture depends on the river\’s flow, against upstream Ethiopia, which is building Africa\’s biggest hydroelectric dam.
There have been threats of war over the $5-billion dam, but researchers hope they have come up with the bones of a win-win deal that gives more water and electricity to both countries. They are now pressing for its inclusion in a final deal on the dam to be signed next year.
Ethiopia began construction of the Grand Ethiopian Renaissance Dam in a gorge of the Blue Nile, the Nile\’s biggest tributary, in 2011 and expects to have it up and running in 2017. The dam will be able to hold back the entire flow of the Blue Nile for more than a year, potentially cutting supplies to Egypt and Sudan (see map).
But on 23 March, the three governments announced a surprise preliminary agreement to share the water. Behind the move was an optimistic assessment by international hydrologists and engineers, which has now been made public.
The solution involves reducing the losses to evaporation from Lake Nasser, the reservoir behind Egypt\’s Aswan High Dam in the Nubian desert. Up to 16 cubic kilometres of water evaporate annually from its surface – a quarter of the Nile\’s average flow and up to 40 per cent in a dry year.
Storing more of that water in the reservoir behind Ethiopia\’s dam could cut those losses, as it is deeper, has a surface area less than a third as great and sits in the cool and wet highlands. But it would also cut Egypt\’s electricity generation, so Ethiopia would need to share electricity from its new dam, says Kenneth Strzepek at the Massachusetts Institute of Technology.
Sudan, too, could benefit from the dam and a more even water flow, reducing the risk of flooding and increasing the potential for irrigation. \”The government of Sudan is already selling land leases for new farmland by the river,\” says Alex de Waal of the World Peace Foundation at Tufts University in Boston.
This article appeared in print under the headline \”Avoiding war over Ethiopia\’s Nile dam\”