1 acre-foot = 43,560 cu.ft. = 325,825 gals.
1 cu. ft. = 7.48 gals = 62.427 lbs.
1 U.S. Gallon = 0.1337 cu. ft. = 8.330 lbs.
1-1/2 cu. ft./sec. = approx. 1,000,000 gals/day.
Average rainfall for U.S. = 30“/year.
Evapo-transpiration is approx 2/3 annual rainfall.