What happens to a river when sediment is deposited along its banks?

Erosion and deposition are two continuous processes during the river flow. Typically, when a river comes across a "bend," the erosion takes place on the outer side of the bend, and the deposition takes place along the inner side of the bend. This happens because the water flows at a faster speed on the outer side of the bend as compared to the inner side. This continuous erosion and deposition causes the bend to "move" and the river to meander. Over a large period of time, this may cause the river's course to change. In some cases, the bend may become very large and may be cutoff from the river itself. In the short run, the river channel may become narrower due to deposition along banks.
Such erosion and deposition are typically observed during the middle course of the river. During the lower course, the river deposits most of the sediments that it carries, and a delta may be formed.
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