Erosion is one aspect of water quality that can impact many others. Although the amount of erosion is not usually measured to determine the quality of a river or lake, its influence on other water quality issues should be noted.

Erosion is the process by which land is removed and the remaining land being essentially smoothed out. This occurs with moving water which is usually a river.

A key factor that determines the places in which water erodes is geography. In most instances, erosion is most significant when the path of the water begins to turn. Objects, including water, usually travel in straight lines, and so when the river bends, the water wants to continue to travel straight. This causes more friction between the shoreline and the water, and as a result many sediments are eroded away.

This issue creates an elevated amount of solids on the river, and carries these particles until they are deposited in another part of the stream.