flood plain

American  

Or floodplain

noun

1. a nearly flat plain along the course of a stream or river that is naturally subject to flooding.

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flood plain British  

noun

1. the flat area bordering a river, composed of sediment deposited during flooding

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Etymology

Origin of flood plain

First recorded in 1870–75

Example Sentences

The land sits on low ground and would need fill for any redesign, to get it above the Potomac river flood plain.

From The Wall Street Journal

That designation involves even more restrictions than the 100-year flood plain, generally prohibiting new construction and significant renovations to existing buildings.

From The Wall Street Journal

Texas lawmakers this month passed new laws barring summer camps from having cabins in flood plains.

From The Wall Street Journal

It might be that in an era of what researchers are calling “mega rain” events, a flood plain should now be off-limits.

From Salon

He even ordered the Army Corps of Engineers to release millions of gallons into a flood plain and then weirdly claimed that he'd "invaded" Los Angeles and solved its water problem.

From Salon