Ruvuma and Southern Coast Rivers
The mean temperature in the coastal area is 260oC and that of the hinterland is 240oC. Annual and daily variations in temperature are small. Geomorphology: African, Post African and Congo/Coast land surfaces largely occupies the basin. Gondwana land surface occupy a small part near Songea. Coastal land surface covers Mtwara and Newala Districts. Post African land surface covers Nachingwea, Masasi and part of Tunduru Districts while the African land surface covers the rest of Tunduru, Songea and part of Mbinga Districts. Geology: Dominant rocks in the basin are Karoo and Usagaran crystalline limestone series of Masasi. The main catchments lie on an altitude between 305 – 710 m above mean sea level and drops almost gradually before entering the coastal plains. The Ruvuma River is shared by Tanzania and Mozambique and drains into Indian Ocean. It has the length of about 800 km of which about 650 km forms the border between Tanzania and Mozambique.