Natural Levee

natural levee

[′nach·rəl ′lev·ē]
(geology)
An elongate embankment compounded of sand and silt and deposited along both banks of a river channel during times of flood.

Natural Levee

 

a gently sloping bank that forms in the part of the floodplain adjacent to the channel, where the flow of floodwater from the channel to the floodplain is slowed down and coarse-grained material, primarily sand, is deposited. On large flatland rivers, such as the Mississippi, natural levees may be up to 5–6 m high and 4.5–5 km wide.

References in periodicals archive ?
Once the water level in Pampanga River rises over a natural levee, it overflows toward Candaba Wetlands, which is relatively lower than the levee.
Constructed over centuries, this natural levee contains smaller floods while the largest floods overflow it and build it higher Natural levees, which run the length of the river are made of the fine silts and clays that compact when the water goes down.
The newly acquired tribal property is on part of a natural levee that extends northwest from the former Thibault Plantation to the Clinton National Airport.
Perilous Place, Powerful Storms begins with the history of New Orleans' chronic flood problem, which was accentuated as the city expanded into low-lying areas, that is, away from the natural levee. Starting with the continuous efforts to stave off the annual floods of the Mississippi River, Colten relates how the need for hurricane protection levees developed.
According to them, the upper 7-m-thick part is recognized as a natural levee to floodplain deposits.
The levee at the Sauve plantation upstream gave way, and water careened off Metairie Ridge, a relict river in which sedimentary deposits had created a crescent-shaped natural levee (see map, p.11).
Unlimited hydroplanes roar by at speeds of up to 200 miles per hour, while families picnic under the trees on Madison's natural levee. The Governor's Cup race is the culmination of a week of community activities, including a parade and a balloon race.
High water can cover all these subtle topographies, but a swamp veteran like Charlie, or any local crawfisherman, will know when he's passing over a drowned waterway, or crossing a natural levee.
The transects, with a combined length of 1500 m followed a moisture and elevation gradient from a mesic natural levee (53.4 m above sea level) through a bottomland oak flat, to a cypress swamp (50.6 m above sea level).
Digging into a high natural levee paralleling the Mississippi River, University of Wisconsin-Madison archaeologists have discovered an ancient campsite or village that recurrently was occupied by a procession of native cultures for almost three millennia.
And natural levees, back swamps and coastal swamps between 100 million and 84 million years ago
Extensive floodplain wetlands along the creek are maintained by small natural levees. To minimize impact to these wetlands, the inset floodplain was limited to a width that would not completely remove the levee and drain the floodplain wetlands.