Overwash

Overwash is the flow of water and sediment over the crest of the beach that does not directly return to the water body (such as ocean, sea, bay or lake; hereafter, ocean) where it originated after water level fluctuations return to normal. There are two kinds of overwash: overwash by runup and overwash by inundation. In the fields of coastal geology and geomorphology, 'overwash' refers to a landward flux of sediment due to overtopping of a dune system.