Acre-foot

Non-SI unit of volume

The acre-foot is a non-SI unit of volume equal to about 1,233 m³ commonly used in the western United States in reference to large-scale water resources, such as reservoirs, aqueducts, canals, sewer flow capacity, irrigation water, and river flows. An acre-foot is approximately the volume of water needed to fill an eight-lane swimming pool, 82 ft (25 m) long, 52 ft (16 m) wide and 9.8 ft (3 m) deep.

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