Natural levee
Also called: Levee · Topic: Landforms and their Evolution: Rivers, Groundwater, Glaciers, Waves and Wind · NCERT: Class 9, Ch 2 "Shaping of the Earth's Surface"; Class 11, Ch 6 "Landforms and their Evolution"
Meaning
A natural levee is a low, long ridge of coarse sediment that runs along the banks of a large river. It forms during floods. When water spills over the bank, it slows down at once and drops its heaviest load first, close to the channel. Finer silt is carried further onto the floodplain. Each flood raises the ridge a little more. Levees stand slightly higher than the land around them, so villages are often built on them.
Example
Natural levees line the banks of the Ganga in the plains of Bihar, where villages often sit on the slightly higher ground next to the river.
Don't confuse with
- Embankment (artificial levee): people build these walls to hold back floods, as along the Kosi. A natural levee is built by the river itself.
- Point bar: a point bar is a deposit on the inner bank of a meander. A levee runs along the banks of the river.
Related concepts
- Alluvial fan
- Distributary
- Delta
- Estuary
- Floodplain
- Point bar
- Meander
- Slip-off slope and undercut bank
- Oxbow lake
- Braided channel