For 10 years Ethiopia has failed to reach an agreement with Egypt and Sudan on how quickly the reservoir should be filled On the eve of the summer rains on the Ethiopian Highlands, the dam is all but complete and filling is about to begin LONDON: In the decade since Ethiopia announced it was going to build Africa’s biggest hydropower dam on the Blue Nile, the source of the bulk of Egypt’s water, the prospect has loomed over Egyptians as an existential threat. For 10 years Ethiopia has failed to reach an agreement with Egypt and Sudan, its two downstream neighbors, on how quickly its vast reservoir should be filled, and how the electricity-generating Grand Ethiopian Renaissance Dam will be operated in the years to come. Now, on the eve of the anticipated annual summer rains that fall on the Ethiopian Highlands, the dam is all but complete and filling is about to begin in earnest. DEEP DIVE: For a longer, interactive version of this story: https://www.arabnews.com/BattleForTheNile