Water politics in the Nile Basin share the river – Egypt, Sudan, Ethiopia, Uganda, Kenya, Tanzania, Burundi, Rwanda and the Democratic Republic of Congo with Eritrea as an observer. During the colonial period, Britain effectively controlled the Nile through its military presence in Africa. Since Sudanese independence, Sudan has renegotiated with Egypt over the use of the Nile waters. The 1959 agreement between Sudan and Egypt allocated the entire average annual flow of the Nile to be shared among the Sudan and Egypt at 18.5 and 55.5 billion cubic meters respectively, but ignored the rights to water of the remaining eight Nile countries. Ethiopia contributes 80%
Sobat River its name. The Sobat and its tributaries drain a watershed approximately in size. The river's mean annual discharge is 412 m³/s (14,550 ft³/s). Sobat River The Sobat River is a river of the Greater Upper Nile region in northeastern South Sudan, Africa. It is the most southerly of the great eastern tributaries of the White Nile, before the confluence with the Blue Nile. The Sobat River is formed by the confluence of the west-flowing Baro River and the north-flowing Pibor River, on the border with Ethiopia. The river enters the White Nile at Doleib Hill, near the city of Malakal