Case Study: Bakken Shale

The Bakken Formation is an unconventional shale play stretching underneath North Dakota, Montana, and Canada. The challenges of the Bakken Formation are the challenges of all unconventional plays around the country. Operators must first source enough water to complete their hydraulic fracturing operations. Then during production they must dispose of the flowback and produced water in an environmentally sound manner that meets regulatory requirements. Let’s look at some statistics during the first decade of the Shale Boom to see the early impact of Bakken exploration and production on water consumption.

Mean hydraulic fracturing water use in the Bakken Shale region peaked in the year 2014 at just under 4.5 million gallons per well.¹Dr. Bridget Scanlon, 2016, personal communication The region has adapted to the increase in water use with a multisource approach. Operators have stewardship of 100,000 acre-feet of water per year from Lake Sakakawea. Water projects such as the Western Area Water Supply Project are expanding to meet demand. Municipalities are expanding their water treatment capacity and infrastructure, and many different agencies are collaborating to modify the hierarchy of water appropriation in the region. For example, operators cannot use the Fox Hills-Hell Creek aquifer for hydraulic fracturing, as it is reserved for livestock mainly watered by flowing artesian wells.

In the years between 2008 and 2014, the ratio of flowback-produced water to oil produced increased.²ibid. Operators produced relatively more water and relatively less oil per well as the wells aged. As a result, there was a significant increase in salt water disposal. Annual disposal volume in 2014 topped out at almost 14 billion gallons. For comparison, water injection from conventional production was around 1 billion gallons in the same year.

What does all of this mean? Production in the Bakken Shale Play is continuing, requiring more water for fracturing and producing more water per barrel of oil. Matching water demand in the region to water supply requires critical analysis of cross-sector use cases and collaboration between a variety of stakeholders. Produced water treatment and management remains a challenge but also an opportunity for operators in the area to make informed decisions toward a sustainable future of developing the resource.

The Bakken Region continues to be a significant contributor to both the U.S. energy portfolio. The U.S. Energy Information Administration reports on production and estimated future production in their monthly reports for the Bakken, as shown below in their December 2022 graphs.