Fluvial landforms resulting from deposition

Levees: are natural embankments along the sides of a river’s flood-prone lower course. During flood events, the river overflows onto the floodplain, depositing heavy sediment first (e.g. coarse sand and gravel) at the river’s edge. Over time, repeated flooding builds up these deposits, creating raised ridges known as levees that contain the river within its channel during high-flow events, reducing the risk of flooding.
Floodplains: a broad, flat expanse of land adjacent to a river formed by the deposition of alluvium (fine particles of silt, clay, and sand) during floods. When a river overflows, its velocity drops significantly, allowing finer sediments to settle across the valley floor. Over many flood cycles, these deposits build up to create fertile, level land, providing nutrient-rich soils for agriculture and supporting diverse ecosystems.
Estuaries: a partially enclosed coastal body of water where freshwater from a river meets and mixes with ocean saltwater. As the river approaches the sea, its flow slows dramatically, causing sediment carried from upstream to settle and form mudflats which can be colonised by salt-tolerant vegetation, leading to the development of salt marshes. Estuaries are highly productive environments that support a wide range of wildlife between river and marine ecosystems.

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