Much pipeline development in the Bakken region of North Dakota and Montana is focused on transporting crude oil. But pipe is also being laid to carry a humble commodity essential to oil production in the region: water.
Copious amounts of water are required to extract oil from the Bakken’s shale beds. The fracking process—injecting a mixture of water and chemicals into shale rock to release oil—consumes up to 8 million gallons of freshwater per well. And along with oil and natural gas, wells produce even larger amounts of subterranean saltwater over their operating life. “The first thing that’s produced out of a well is water; the last thing ever produced out of a well is water,” said Rodney Wren, president of New Frontier Midstream, a Texas-based developer of oil and gas infrastructure.
Today, most freshwater used for fracking is trucked to wellheads, and tanker trucks also haul away saltwater and used frac (“flow back”) water for disposal in deep wells. Trucking water raises costs for producers—fees in the Bakken range from 2 to 10 cents per gallon, depending on miles traveled—and contributes to wear and tear on rural roads.
It’s cheaper to pipe water to and from the wellhead, especially in areas where wells are close together. Brigham Exploration, an oil company acquired by Statoil of Norway in 2011, was a leader in laying water pipelines in the Bakken, installing them simultaneously with crude oil and gas lines. Incoming pipe delivers freshwater for fracking from municipal or rural water systems; outgoing pipelines carry away wastewater for disposal.
There are no public data on oil-industry water networks in the Bakken, but Statoil, New Frontier and other petroleum and energy transportation firms are laying new water pipe to wellheads. New Frontier has plans to build wastewater gathering systems and disposal wells near Dickinson, N.D., and Sidney, Mont., to serve oil and gas producers in those areas.
The next step in oilfield water management is recycling frac flowback water. Statoil has tested a fracking method that uses a 50:50 mixture of flow back water and freshwater. The company aims to raise the proportion of flow back water used to 80 percent—greatly reducing the volume of freshwater that must be transported to the wellhead.
For much more on pipelines and other energy transportation infrastructure in the Bakken, look for the upcoming April issue of fedgazette.