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%
Nile enormous swamps of the Sudd region of South Sudan. More than half of the Nile's water is lost in this swamp to evaporation and transpiration. The average flow rate of the White Nile at the tails of the swamps is about . From here it soon meets with the Sobat River at Malakal. On an annual basis, the White Nile upstream of Malakal contributes about fifteen percent of the total outflow of the Nile. The average flow of the White Nile at Lake Kawaki Malakal, just below the Sobat River, is ; the peak flow is approximately in October and