natural levee

American  

noun

1. a deposit of sand or mud built up along, and sloping away from, either side of the flood plain of a river or stream.

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Example Sentences

The entire delta, under natural conditions, lay above sea level, ranging from a few inches along the coastal fringe to over a dozen feet high at the crest of the Mississippi River’s natural levee.

From Scientific American

Throughout New Orleans’ first two centuries, development was densely clustered on this natural levee, making residents less vulnerable to flooding.

From The Guardian

Photograph: General Photographic Agency/Getty But massive drainage systems installed in the late-19th and early 20th centuries emptied out city-owned cypress tree swamps behind the natural levee.

From The Guardian

Each side of the channel is thus raised so as to form what is termed a natural levee.

From Project Gutenberg

The wetlands also act as a natural levee with its grasses and bushes slowing water from moving inland when storms hit the Gulf.

From Reuters