How many?

Acre Feet

The acre-foot is a unit of volume commonly used in the 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 equals approximately an eight-lane swimming pool, 82 ft (25 m) long, 52 ft (16 m) wide and 9.8 ft (3 m) deep. Lake Mead which is the reservoir created by the Hoover Dam has a capacity of 30,500,000 acre feet.

Board Feet

The board foot or board-foot is a unit of measurement for the volume of lumber in the United States and Canada. It equals the volume of a one-foot (305 mm) length of a board, one foot wide and one inch (25.4 mm) thick. How many board feet of lumber is needed to build a house? A 2,000 square foot home would use around 16,000 board feet of lumber.