Ruzizi River

Ruzizi River
Hippopotami in the Ruzizi River in Burundi
Location
Countries	DR Congo (DRC) Rwanda Burundi
Physical characteristics
Source	Lake Kivu
• location	border between Bukavu and Cyangugu, South Kivu, DRC
• coordinates	02°29′27″S 28°53′35″E / 2.49083°S 28.89306°E / -2.49083; 28.89306[1]
• elevation	1,472 m (4,829 ft)[2]
Mouth	Lake Tanganyika
• location	west of Bujumbura, Burundi, Bujumbura Rural Province
• coordinates	03°21′51″S 29°16′04″E / 3.36417°S 29.26778°E / -3.36417; 29.26778[1]
• elevation	768 m (2,520 ft)[2]
Length	117 km (73 mi)[3]
Discharge
• average	100 m3/s (3,500 cu ft/s)[4]

The Ruzizi (also sometimes spelled Rusizi, French: Rivière Ruzizi) is a river, 117 kilometres (73 mi) long,^[3] that flows from Lake Kivu to Lake Tanganyika in Central Africa, descending from about 1,500 metres (4,900 ft) to about 770 metres (2,530 ft) above sea level over its length.^[2][5] The steepest gradients occur over the first 40 kilometres (25 mi), where hydroelectric dams have been built.^[4] Further downstream, the Ruzizi Plain, the floor of the Western Rift Valley, has gentle hills,^[6] and the river flows into Lake Tanganyika through a delta, with one or two small channels splitting off from the main channel.^[5]

The Ruzizi is a young river, formed about 10,000 years ago when volcanism associated with continental rifting created the Virunga Mountains. The mountains blocked Lake Kivu's former outlet to the drainage basin of the Nile and instead forced the lake overflow south down the Ruzizi and the drainage basin of the Congo.