Throwing water away
The most common solution, in the end, remains simply to inject the contaminated water down a disposal well that penetrates deeper than any drinking-water resources. More than 90 percent of the water used or produced in oil and gas operations is disposed of in this way, in the nation's more than 150,000 such wells. More and more new disposal wells are being drilled to cope with the rising flood of frack water.
But this injected water is lost forever. Some states such as Pennsylvania also make it difficult to drill such wells, which means operators fracking the Marcellus Shale there must pay to truck the produced water to Ohio for disposal. That can cost as much as $15 a barrel, and "sooner or later Ohio is going to get a bit panicky about that," Bajpayee notes. In addition, it costs at least $5 million to drill each new disposal well.
In states such as Texas that are enduring prolonged droughts, the millions of liters of water required to frack new wells grows more and more problematic. Pennsylvania suspended water use for fracking in some parts of the state this spring due to drought. As Veolia's Hopper argues, "with the water scarcity trends that we see, the trend will be to reduce the net usage of water." After all, reducing the dependence of energy supplies on water—whether drilling for oil and natural gas or generating electricity—will be critical to ensuring there is enough energy and water to go around.