When a large tanker truck pulls up to a fire hydrant in Greeley, Colo. -- a midsize town on the semiarid Eastern Slope of the Rocky Mountains -- and starts siphoning water from the city's supply, passersby start looking nervous.
Chances are good the tanker is on its way to an oil or natural gas field, where the water will either go to drilling or be injected underground to reach previously inaccessible resources via a process known as hydraulic fracturing, or "fracking."
Such water transfers are becoming an increasingly common sight. But in a region that has battled drought on and off for decades, and where state officials predict there won't be enough water to sustain expected population and agriculture levels in the not-too-distant future, the tankers spark questions about how water is being used.
A high-profile groundwater contamination case in Pavillion, Wyo., is the latest to stir public debate on the pollution that can stem from hydraulic fracturing, but the amount of water used during extraction is an issue just starting to surface.
In what many are calling the first attempt to document how much water is required for hydraulic fracturing in the Centennial State, the Colorado Oil and Gas Conservation Commission (COGCC) released a fact sheet late last month that projected a 35 percent increase from 2010 to 2015 in water use for oil and gas exploration and production.
Water demand for hydraulic fracturing in the state is expected to increase from roughly 4.5 billion gallons in 2010 to more than 6 billion gallons in 2015, a jump that could supply more than 160,000 people with domestic water for a year.
In fracking, water is used to increase well production. Chemically treated water is pumped into the earth at high pressures, forcing open fissures that allow deep deposits of oil and natural gas to flow into wells.
A typical well site can require anywhere from 200,000 to 5 million gallons of water a year, according to Tisha Schuller, president and CEO of the Colorado Oil and Gas Association (COGA), which represents industry interests. That includes water for drilling and in some cases multiple rounds of hydraulic fracturing.
The amount of water used depends on the geology of the region and whether wells are drilled horizontally or vertically, according to the COGCC. Horizontal wells require more, as do shale formations located deep underground.
COGCC estimates that between 2010 and 2015, barring any major economic, environmental or technological changes, the number of active oil and gas wells in Colorado is likely to remain steady, with much of the expected 1.5-billion-gallon increase in water use linked to an expected swing from vertical oil drilling to new horizontal technologies.
For more information on how fracking might be effecting you and your water levels, continue reading here.
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