Denver Post: A worker monitors water pressure and temperature at an Encana hydraulic-fracturing site outside Rifle. The process splits open oil- and gas-bearing rock often located more than a mile underground. (Associated Press file)
The move to tap petroleum-rich shale reserves in some of the country's driest regions, including Colorado, may be setting up a battle between oil and water.
The water is needed for hydraulic fracturing, a process that pumps millions of gallons of sand and water into a well...