Did You Know? Rainwater Harvesting Facts..... 50% to 60% of water used is outside the home or business. .....Fact..... The average American uses 165 gallons of water per day. .....Fact..... 4% of Electricity in America is used to move water. .....Fact..... 1" of rain on 1 acre of land produces 27,000 gallons of water. .....Fact..... 1" of rain on a 20 by 50 mile area results in 17.4 Billion gallons of water. .....Fact..... Water can be cleaned by aquatic plants which are known as the "Kidneys of the Earth." .....Fact.....