"It is estimated that more than 5 million gallons of water per day are used in fracturing operations." ( p. 26 of 34. )
This 2006 Powerpoint may represent the only scholarly study found to date that indicates an accurate estimate of the amount of water used per day in hydrofracking. Further research into this estimated amount is required.
Presented at “The Future of Desalination in Texas,” Global Petroleum Research Institute, Texas A&M University, College Station, Texas, Aug. 6-8, 2006.