Jan 25, 2022 - News

Dakota Access Pipeline hurt Iowa crop yields, study shows

A photo of the Dakota Pipeline project through an Iowa field.

Keokuk County farmer Steve Roquet says this picture shows how some of the most fertile topsoil in his field was in 2016 buried feet underground as part of the Dakota Access Pipeline. Photo courtesy of Steve Roquet

Iowa's soil in the right-of-way of the Dakota Access Pipeline is still recovering roughly six years after the project was installed.

Why it matters: Three companies are proposing new pipeline projects that would cross Iowa to capture carbon dioxide from ethanol and fertilizer plants.

  • Environmental impacts and the future of agriculture in the area are under debate.

Threat level: During the two crop seasons after the Dakota Access Pipeline's installation in 2016, crop yields in the right-of-way of the project fell as much as 25%, according to an Iowa State University study published late last year.

  • Recovery is ongoing, researchers found.

Catch up fast: The nearly 1,200-mile Dakota underground pipeline cuts diagonally across Iowa to an oil terminal near Patoka, Illinois. It went into service in 2017.

  • About 150 feet of right-of-way was necessary for pipeline trenching and construction, including portions of an ISU agricultural research farm near Ames.

What they found: The project caused severe subsoil compaction and impaired soil structure that can discourage root growth and reduce water infiltration, ISU researchers concluded.

What they're saying: The three proposed carbon pipelines may not be as big or deeply trenched. If that's the case, it could help minimize yield losses, Mehari Tekeste, an assistant agriculture professor who led the study at ISU, told Axios last week.

  • Navigator CO2 Ventures — whose proposal includes areas in northern Polk County — is confident that crop losses would be short term due to a restoration process, spokesperson Andrew Bates told Axios yesterday.
  • Farmers will get a 240% reimbursement for yield losses throughout the life of the Navigator project, Bates said.

The other side: Keokuk County farmer Steve Roquet told Axios that Dakota Pipeline officials made him a similar 240% reimbursement promise in 2016.

  • But it's calculated in such a way that it fails to fully cover losses, he said.

Of note: Dakota Access Pipeline officials didn't return a call seeking comment.

What to watch: If Navigator's proposal gets state approval, construction could begin in 2024.

A map of a proposed pipeline project in Iowa.
Navigator CO2 Ventures' pipeline would cross 36 of Iowa's 99 counties, including Polk. Map courtesy of Navigator CO2 Ventures

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