Avulsion

The loss of land as a result of its being washed away by a sudden or violent action of nature. A riparian owner generally does not lose title to land lost by avulsion—the boundary lines stay the same no matter how much soil is lost, and the former owner can reclaim the lost land. In contrast, the riparian owner loses title to land washed away by erosion, which is the gradual and imperceptible washing away of soil.