6 - Levee along the Sacramento River, USĪ braided channel or river is a river that is divided into smaller channels. These levees are defences against potential floods, depending on their height.įig.
Now, the water will deposit sediments there, with coarser, heavier materials deposited first, creating a raised bank, known as a levee (sometimes spelt levées), at the river's edge. 5 - Floodplain on the Isles of Wight after a massive floodĪ floodplain will seriously reduce the water's velocity by causing friction.
Over time, the floodplain builds up and becomes higher.įig. The flow of water slows down, and the energy is taken out of the river - this means the material is deposited. When a river floods, the water-covered area is called a floodplain. In the end, the only thing left is what we call a 'meander scar', a visual reference that once there was a meander (that became an oxbow lake). Therefore, over time, the lake will silt up and become a bog or swamp before evaporating entirely at some point. 3 - Oxbow lake in Lippental, Germanyįun Fact: Oxbow lakes are still water lakes, meaning no current flows through the water. Oxbow lakes often have the rough shape of a horseshoe.įig. In due course, the deposition can cut off that meander (loop) from the rest of the river, creating an oxbow lake. 2 - Meanders of the Rio Cauto in CubaĮrosion causes the outer banks to grow wider and create bigger loops. The result is a steep cliff on the outer bank and a nice, gentle slip-off slope on the inner bank.įig. The water flows faster on the outer banks, causing erosion, and slower on the inner banks, causing deposition. These curves mean that the water flows at different speeds. Meanders are loopy! These rivers curve along their route in a loop-like pattern rather than going in a straight line. In order to become a delta, the sediment must enter water that moves slower or is stagnant, which often is where a river enters an ocean, sea, lake, reservoir, or estuary. Alluvial fans are found in the river's middle course at the foot of a slope or mountain.ĭeltas, flat, low-lying deposits of sediments, can be found at a river's mouth. When water is confined in a channel, it can then freely spread out and infiltrate the surface, depositing sediments you will see that it has a cone shape. TypeĪlluvium is gravel, sand, and other small(er) material deposited by flowing water. There are several types of river deposition landforms, so let's look at them now. The river reaches its mouth - the river reaches flatter land, so gravity isn't pulling the river down the steeper slopes.The water is or becomes shallower - if evaporation is higher or there is less rainfall.The eroded materials increase - the buildup will slow down the river's current.Falling river volumes - for example, during a drought or following a flood.What are some of the reasons a river slows down, you ask? Well, the reasons include the following:
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