Which geological feature helps to prevent flooding along riverbanks?

Levées are natural or man-made embankments that run parallel to riverbanks. Their primary function is to prevent flooding by containing the flow of the river during periods of high discharge, such as during heavy rainfall or snowmelt. When rivers overflow, levées can help ensure that water does not spread into the surrounding land, thus minimizing the risk of extensive flooding in nearby areas.

Levées are built up over time by sediment deposited during floods, as well as through human activities, making them effective in protecting agricultural land, infrastructure, and communities situated close to riverbanks. Their structure allows them to absorb and redirect the flow of excess water, offering a crucial line of defense against floodwaters.

In contrast, other options like dikes are typically used in coastal areas to prevent seawater intrusion, while berms do not offer significant flood protection compared to levées. Cliffs provide natural barriers but do not inherently function to prevent flooding along rivers. Thus, levées are particularly significant in flood management along river systems.