Chad Basin demand for ivory, but stocks have since recovered. The seasonal Korama River in the south of Niger does not reach Lake Chad. Nigeria includes two sub-basins that drain into Lake Chad. The Hadejia - Jama'are - Yobe sub-basin in the north contains the Hadejia and Jama'are rivers, which supply the Hadejia-Nguru wetlands. They converge to form the Yobe, which defines the border between Niger and Nigeria for , flowing into Lake Chad. About of water reaches Lake Chad annually. Construction of upstream dams and growth in irrigation have reduced water flow, and the floodplains are drying up. The Yedseram -
Geography of Chad where its borders converge, Chad's average width is about 800 kilometers. Its area of 1,284,000 square kilometers is roughly equal to the combined areas of Idaho, Wyoming, Utah, Nevada, and Arizona. Chad's neighbors include Libya to the north, Niger and Nigeria to the west, Sudan to the east, Central African Republic to the south, and Cameroon to the southwest. Chad exhibits two striking geographical characteristics. First, the country is landlocked. N'Djamena, the capital, is located more than 1,100 kilometers northeast of the Atlantic Ocean; Abéché, a major city in the east, lies 2,650 kilometers from the Red Sea; and Faya-Largeau,