floodplain
n. countable B2 Upper Intermediate US //ˈfɫədˌpɫeɪn// UK //flˈʌdpleɪn// flood·plain
n. an area of land next to a river that is often flooded when the water level rises. This land is usually flat and very good for farming.
n. an area of land adjacent to a river or stream that is susceptible to flooding during periods of high discharge. Often characterized by fertile soil due to the deposition of silt during inundation.
The farmer lives on a floodplain near the river.
Many ancient civilizations, such as the Egyptians, settled on floodplains because the soil was so rich for growing crops.
While the floodplain provides highly productive agricultural land, modern urban development in these zones often requires significant investment in levees and drainage systems to mitigate seasonal flood risks.
From flood + plain.