The Pibor River (also called the River Pibor) is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

in eastern

South Sudan South Sudan (; din, Paguot Thudän), officially the Republic of South Sudan ( din, Paankɔc Cuëny Thudän), is a landlocked country in East Africa. It is bordered by Ethiopia, Sudan, Central African Republic, Democratic Republic of the C ...

, which defines part of South Sudan's border with

Ethiopia Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the ...

. From its source near Pibor Post it flows north for about , joining the Baro River to form the

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. Geography The Sobat River is ...

, which is a tributary of the

White Nile The White Nile ( ar, النيل الأبيض ') is a river in Africa, one of the two main tributaries of the Nile, the other being the Blue Nile. The name comes from the clay sediment carried in the water that changes the water to a pale color. ...

. The Pibor and its tributaries drain a watershed in size. The river's mean annual discharge at its mouth is 98 m³/s (3,460 ft³/s).

Course

The Pibor River is formed by various streams that come together at Pibor Post, a colonial era outpost built in 1912 and originally called

Fort Bruce Fort Defiance (formerly also known as Fort Sevier and Fort Bruce) was a fort built during the American Civil War at Clarksville, Tennessee, on the Cumberland River. It changed hands several times during the war, and is now preserved by the city ad ...

. The Pibor flows north, receiving the

Akobo River The Akobo River is a river on the border between South Sudan and Ethiopia. From its source in the Ethiopian Highlands near Mizan Teferi it flows west for to join the Pibor River. The Pibor flows into the Sobat River, which in turn empties into t ...

near Akobo. Continuing north the Pibor receives the

Gilo River The Gilo River is a river in the Gambela Region of southwestern Ethiopia. It is also known by a variety of names: the Gimira of Dizu call it the "Mene", while the Gemira of Chako call it "Owis", and Amhara and Oromo settlers in the early 20th ce ...

and Bela Rivers on the right, then joins the Baro River, forming the Sobat River.

Natural history

The Pibor, Baro, Gilo, and Akobo rivers all drain the

Ethiopian Highlands The Ethiopian Highlands is a rugged mass of mountains in Ethiopia in Northeast Africa. It forms the largest continuous area of its elevation in the continent, with little of its surface falling below , while the summits reach heights of up to . ...

. The Baro River is by far the largest, contributing 83% of the total water flowing into the Sobat River. During the rainy season, between June and October, the Baro River alone contributes about 10% of the Nile's water at

Aswan Aswan (, also ; ar, أسوان, ʾAswān ; cop, Ⲥⲟⲩⲁⲛ ) is a city in Southern Egypt, and is the capital of the Aswan Governorate. Aswan is a busy market and tourist centre located just north of the Aswan Dam on the east bank of the ...

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...

. In contrast, these rivers have very low flow during the dry season.

History

The boundary between

Sudan Sudan ( or ; ar, السودان, as-Sūdān, officially the Republic of the Sudan ( ar, جمهورية السودان, link=no, Jumhūriyyat as-Sūdān), is a country in Northeast Africa. It shares borders with the Central African Republic t ...

and

was defined for the region near the Pibor River in 1899 by Major H.H. Austin and Major Charles W. Gwynn of the British

Royal Engineers The Corps of Royal Engineers, usually called the Royal Engineers (RE), and commonly known as the ''Sappers'', is a corps of the British Army. It provides military engineering and other technical support to the British Armed Forces and is heade ...

. They had no knowledge of the land, its inhabitants, or their languages, and were short on supplies. Rather than defining a line based on ethnic groups and traditional territories, essentially along the escarpment that separates the Ethiopian Highlands and the plains of the Sudanian Savanna, they simply proposed a line drawn down the middle of the Akobo River and parts of the Pibor and Baro rivers. This boundary was consummated in the Anglo-Ethiopian Treaty of 1902, resulting in an area in Ethiopian

Gambela Region The Gambela Region (also spelled Gambella; am, ጋምቤላ), officially the Gambela Peoples' Region, is a regional state in western Ethiopia, bordering South Sudan. Previously known as Region 12, its capital is Gambela. The Region is situated ...

called the Baro Salient. This area is more closely connected to South Sudan than Ethiopia, both in terms of natural features and people. The Baro Salient was used as a sanctuary by Sudanese insurgents during the country's long civil wars. It was difficult for Sudan to exert authority over a region that is part of Ethiopia, and Ethiopia was reluctant to police this remote region and become involved in the politics of Sudan's internal conflicts.; online a
Internet Archive
/ref>

Course

Natural history

History

See also

References

Further reading