As the drought continues and oil and natural gas operations continue to expand throughout the state, companies increasingly are looking for ways to reduce the amount of freshwater they use.
While progress has been made, adoption levels vary widely from state to state and from rock formation to rock formation.
Reuse and recycling is widely used in areas like Pennsylvania where disposal wells are not available. It is growing in popularity in the Permian basin of west Texas, where freshwater is more expensive and harder to find.
But in most of Oklahoma, freshwater is available and relatively inexpensive.
“For a number of our independent operators, it truly is not economically feasible,” said Brian Woodard, vice president of regulatory affairs at the Oklahoma Independent Petroleum Association. “Recycling and reuse have come a long way, but quite frankly, there are still a number of financial and regulatory hurdles.”
Several of the state’s larger operators, however, have taken on recycling projects in the state.
Oklahoma City-based Devon Energy Corp. in 2012 built a pond in Canadian County to hold up 21 million gallons of water. The facility allowed Devon to reuse more than 260 million gallons before the company completed its drilling project in the area late last year.
Devon was able to reuse both the freshwater used in hydraulic fracturing, or fracking, and the produced water, which refers to the water that is recovered along with the oil from deep below the surface. The average oil well in Oklahoma produces about 10 times as much water as oil. The water typically is many times more salty than the ocean.
“We’ve learned quite a bit from the lessons we dealt with by reusing produced water,” said Dean Reynolds, a senior engineering adviser at Devon. “We’ve taken those lessons and used them at other areas of the company.”
In Devon’s operations in Payne County and other parts of the Mississippi Lime formation, Devon has set up a series of three pipelines to connect its wells in the area. The lines transport oil, natural gas and water, reducing truck traffic in the area and allowing the company to transport treated produced water for use in fracking.
“Water management and how we look at water and produced water has been very dynamic and is changing a lot,” Reynolds said. “As a company, our water management philosophy is that we look at recycling and reuse. We look at a lot of reuse projects. They’ve become cost effective versus using surface water. We do use surface water in our locations, but we also use produced water and blend that water so we reduce our amounts of surface water. We’re always looking at where we can improve that and how we can improve that with new technology.”
How it works
Most existing water recycling programs require many wells connected to one system to ensure that there is enough water that can be processed, treated and available to use when the next well is ready. The system works fine for large companies with many wells in the same area, but is more of a challenge for smaller operators.
One challenge is the fact that oil and natural gas operations move around so much. A single well — and even a pad with up to eight wells — is drilled for a few months before the company moves on to the next area. Water and pipeline infrastructure must be flexible enough to move from site to site.
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