Lake Tanganyika Basin
In addition to the Malagarasi, there are smaller basins draining into L. Tanganyika. To the north west of Kigoma, the Luiche is an important river. The lower part of the river forms the Luiche Delta which floods often during the rainy season.
Other major tributaries are the Ruchugi River which drains the hilly landscape north of Kasulu, running in a southerly direction through a low, partly swampy, undulating landscape, before it enters the Malagarasi River at Uvinza.
The Ugalla River drains an area of approximately 52.000km2. and before the confluence with the Malagarasi, it passes through large areas of swamps and marshlands, forming the seasonal Lakes of Sagara and Ugalla.
The basin is dominated by the Malagarasi river system which is 130,000 km2. The main river, the Malagarasi originates in the mountainous area close to the border with Burundi at an altitude of 1750 m.a.m.s.l. from where it runs northeasterly through hilly and mountainous landscape and then southward into the Malagarasi Swamps. Its major tributaries, the Myowosi and Igombe Rivers meet the Malagarasi in the seasonal Lake Nyamagoma. The Ugalla and Ruchugi Rivers join the main river downstream of Lake Nyamagoma. The river then runs west, through the Misito Escarpment where it forms the rapids and waterfalls before entering Lake Tanganyika.
Lake Tanganyika Basin is situated in the Western Part of the country. All the catchments that drain in Lake Tanganyika constitute the Lake Tanganyika basin. The total catchment of Lake Tanganyika basin as a whole is 239.000km2 and the area of the lake is 32,000 km2. The land surface of the basin on Tanzania side is 151,000km2 which contributes 60% of the total runoff to Lake Tanganyika.