Drainage Morphology of Imo Basin in the Anambra – Imo River Basin Area, of Imo State, Southern Nigeria

This study involved the delineation of all the river sub-basins in the Imo Basin of the Anambra-Imo River basin area. It the area drained by measuring all the tributaries and their stream order. This study found out that there are basically five sub-basins in Imo State, viz. Imo River, Upper Orashi, Njaba/Lower Orashi, Otamiri, and Ogechie River sub-basins. All of these rivers and their tributaries cover approximately 5, 493.45 km2 in Imo State. The Imo River is one of the largest river basin covering (1,322.82 km2) and drained through northeast tilted topographic slope and disappears into the Atlantic Ocean near Opobo estuary; while Orashi and Njaba flows northwest and down south to the Bight of Bonny in the Gulf of Guinea - (is a part of the tropical Atlantic Ocean).