Despite the fact that Ethiopia is one of the countries with the highest hydropower potential in Africa with 45,000 MW, only about 5% has been exploited9. In the context of modern development of the country, the Government of Ethiopia is developing the Gibe Hydroelectric Cascade scheme (4,600 MW installed capacity) and the Kuraz Sugar Development Project of about 175,000 hectares in the Omo-Gibe basin with the aim of satisfying energy and water demands and enhancing the national economy. A decrease in the flow of the river, a change in the natural flow pattern and silt trapping, due to the above mentioned projects, would considerably affect the biodiversity of the Lower Omo Valley and also the Lake Turkana, in Kenya, since 80% of its inflow depends on the Omo River.