**At 70 degrees Fahrenheit, one cubic foot of water weighs approximately 62.30 pounds.** Keep in mind, however, that the density of water, and thus its weight by volume, fluctuates based on its temperature. Water that is warmer than 70 F weighs less, while water that is cooler than 70 F weighs more.

According to the USGS Water Science School, a gallon of water at 70 F weighs approximately 8.33 pounds. To arrive at the weight of a cubic foot of water, multiply the weight of one gallon of water by the total number of gallons in a cubic foot, which is 7.48 gallons. The product of the two numbers, and thus the approximate weight in pounds of a cubic foot of water, is 62.30.