[The Conversation Africa] Ethiopia, Sudan and Egypt are a step closer to resolving their disputes over the filling and operation of the Grand Ethiopian Renaissance Dam. The dam - a huge project on one of the River Nile's main tributaries, the Blue Nile in Ethiopia - is designed to generate 6,000 megawatts of electricity. Its reservoir can hold more than 70 billion cubic metres of water. That's nearly equal to half of the Nile's annual flow.