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Published on Sep 17, 2013
How did we come up with the number 4 liters? It's the minimum amount of water a person can live on everyday. It's also the same amount that can change the way you think about water forever. Sign up at 4liters.org
Video by Beverly Rosenzweig Direction and Voice-Over by George McGraw Photos and Video by George McGraw, Ryan Youngblood and WHI