Between Segou and Timbuktu the gradient of the river decreases drastically and forms the Inner Niger Delta. The delta is approximately the size of the country Belgium. The decrease gradient causes the flow of the river to slow down resulting in numerous marches, lakes, and streams. In this area about two thirds of the rivers potential flow is lost, leaking into lakes and marches. When the region floods, during the rainy season, excellent conditions for fishing and farming are created.