An Oxbow lake is a middle-course feature of a river which is caused water eroding the corner of a meander, resulting in an isolated corner containing a body of water. This happens as the velocity of the water constructs a more efficient passage through the river channel. The higher the volume of water and the faster the velocity then the erosion rate will increase. Oxbow lakes are often formed over long periods as meanders generally have large sweeping gaps between each other.