Malagarasi River - Geography

Geography

The Malagarasi is the second longest river in the country, at 475 kilometres (295 mi), and with a basin area of 130,000 square kilometres (50,000 sq mi), the Malagarasi has the largest watershed of all of the rivers flowing into Lake Tanganyika. The source of the river is near the Burundi-Tanzania border. The first 80 kilometres (50 mi) of the river forms the international boundary between Tanzania and Burundi. Several tributaries from the Burundi highlands join its right bank. After the confluence with the Lumpungu River, the Malagarasi enters Tanzania, makes a circle and empties into the eastern side of Lake Tanganyika about 25 miles (40 km) south of Kigoma, near Ilagala. It is one of the lake's primary inflows. Moyowosi River is the principal tributary, along with its affluent the Nikongo River; other tributaries include Ugalla River, Gombe River, Ruchugi River, Lumpungu River, and Nguya River. At a length of 475 kilometres (295 mi), it is the second longest river in Tanzania, and with a basin area of 130,000 square kilometres (50,000 sq mi), the Malagasi has the largest watershed of all of the rivers flowing into Lake Tanganyika. Characterized as a low stream river, its drainage includes four biotopes: swampy areas, river channels, a flowing river with a few moderate rapids, and a large double-branched delta.

The flow of the river ranges dramatically between the annual cycle of wet and dry seasons, and at times may be susceptible to flooding or reduced to a small stream; flow is also affected by local agriculture and deforestation which increase the level of sediments within the river. At Mberagule, the flow of the river has been gauged to be 6.9 cubic kilometers. About 80 kilometres (50 mi) from the mouth, the river flows through the Moyowosi swamplands, an area of "extensive swamps and floodplains" and a "marshy labyrinth". It passes through the Dodoma Belt, a geological area of Archaean and Proterozoic age Precambrian crystalline rocks.