The Chad Basin is the largest endorheic basin in Africa, centered approximately on Lake Chad. It has no outlet to the sea and contains large areas of semi-arid desert and savanna. The drainage basin is approximately coterminous with the sedimentary basin of the same name, but extends further to the northeast and east.
The basin spans four modern nations, including most of Chad and a large part of Niger, Nigeria and Cameroon. A combination of dams, increased irrigation, climate change, and reduced rainfall are causing water shortages. Lake Chad continues to shrink.