Deposition occurs where water is moving the slowest along the inside of the loop.

Erosion by Runoff Gravity causes the water to flow from higher to lower ground. Much of the material eroded by runoff is carried into bodies of water, such as streams, rivers, ponds, lakes, or oceans. Runoff is an important cause of erosion. That’s because it occurs over so much of Earth’s surface.

Thus by eroding its outer bank and depositing material along its inner bank, a stream moves sideways without changing its channel size. Due to the slope of the channel, erosion is more effective on the downstream side of a meander.

A river delta is a landform created by deposition of sediment that is carried by a river as the flow leaves its mouth and enters slower-moving or stagnant water. This occurs where a river enters an ocean, sea, estuary, lake, reservoir, or (more rarely) another river that cannot carry away the supplied sediment.

Wind Deposition All the sediment picked up by wind eventually falls back to the ground. Wind erosion and deposition may form sand dunes and loess deposits. When the wind strikes an obstacle, the result is usually a sand dune. Sand dunes can be seen on beaches and in deserts where windblown sediment has built up.

A floodplain is formed by both erosion and deposition, acting both laterally and vertically. Floodplains are primarily accumulative surfaces typically composed of alluvial deposits, although in some rivers a planation surface cut in bedrock may occur adjacent to the floodplain.

Floodplains are the relatively flat lands adjacent to a body of water, such as a river or stream, that become flooded (inundated with water) when channel capacity is exceeded and overtopping occurs. A commonly overlooked cause of flooding is often as simple as a storm drain blocked by debris.

Flood zones are primarily determined by the history of flooding in the area. Each zone is rated according to the probability of annual flooding.

Most floodplains are formed by deposition on the inside of river meanders and by overbank flow. Wherever the river meanders, the flowing water erodes the river bank on the outside of the meander, while sediments are simultaneously deposited in a point bar on the inside of the meander.

residents of floodplains face the very real risk of flooding and the devastation that it can cause. homes can be damaged or destroyed. property can be ruined. If you live in a floodplain, you can avoid or at least minimize the damage by planning today for flooding that might occur tomorrow.