Could mega-dams kill the mighty River Nile?

Ethiopia is building one of the largest dams in the world, leaving Sudan and Egypt further downstream the Nile at serious risk of water shortages. If Ethiopia fills the dam within three years, Egypt would lose half of its annual water supply. Al Jazeera has produced a compehensive visual piece on the project and its ramifications. (Also, did you know that the Nile flows very slowly? 65 times slower than the Amazon).