…and that’s not taking into account what’s already gone or the worldwide water ruined by shale drilling.
Natural Gas Drilling: What We Don’t Know
by Abrahm Lustgarten, ProPublica –
Another uncertainty arises from the enormous amounts of water needed for “fracking.” The government estimates that companies will drill at least 32,000 new gas wells annually  by 2012. That could mean more than 100 billion gallons of hazardous fluids will be used and disposed of each year if existing techniques, which often involve 4 million gallons of water per well, are used.
And the remaining water could be contaminated by the toxic chemicals mixed with the water and used in hydraulic fracturing.