Zambezi two largest left-hand tributaries of the Zambezi. The Kafue joins the main river in a quiet deep stream about wide. From this point the northward bend of the Zambezi is checked and the stream continues due east. At the confluence of the Luangwa (15°37' S) it enters Mozambique. The middle Zambezi ends where the river enters Lake Cahora Bassa (also spelled Cabora Bassa). Formerly the site of dangerous rapids known as Kebrabassa, the lake was created in 1974 by the construction of the Cahora Bassa Dam. The lower Zambezi's 650 km from Cahora Bassa to the Indian Ocean is navigable,
Zambezi most is lost through evaporation in its swamp systems. The 1940s and 1950s were particularly wet decades in the basin. Since 1975, it has been drier, the average discharge being only 70% of that for the years 1930 to 1958. Up to the Late Pliocene or Pleistocene (more than two million years ago), the Upper Zambezi river used to flow south through what is now the Makgadikgadi Pan to the Limpopo River. The change of the river course is the result of epeirogenic movements that uplifted the surface at the present-day water divide between both rivers. Meanwhile, east, a western