[2] The river crosses the northern part of Togo in a savannah-clad valley some 40 or 50 km (25 or 31 mi) wide.

Along the margins of the river is gallery forest which floods periodically.

Both the Oti and the Koumongou have floodplains, some 10 and 4 km (6.2 and 2.5 mi) wide, respectively.

There is also some small-scale growing of crops, and the hunting of game takes place there.

[3] The river forms part of the international borders between Ghana, Burkina Faso, Togo, and Benin.