US Supreme Court to hear arguments in Enbridge’s Line 5 operation case

LANSING — The battle around Enbridge’s Line 5 entered a new phase this week, potentially impacting the current line’s operation and the proposed protective tunnel project.

The US Army Corps of Engineers concluded its 30-day public comment period for the project Monday, while the US Supreme Court agreed to hear a dispute on potential state action against the pipeline.

“All these decisions are happening simultaneously, and they could create a perfect storm that either kills the project or locks it in for decades to come,” said David Holtz, a member of the Sierra Club’s Board of Directors.

The high court will not rule on Line 5’s operation itself — they will just decide whether the arguments should be held in state or federal court.

“Federal courts are seen as being more favorable to corporations and interstate commerce, and states are more favorable to protecting, in Michigan’s case, the Great Lakes,” Holtz said.

Last year, a court of appeals ruled that Enbridge’s request to move the case to federal court came too late in the process, a decision that the company disagrees with.

The Supreme Court will hear arguments in the case sometime after their next term begins in October. A ruling could come any time after that, as late as June 2026.

While that debate is ongoing, authorities will still be moving forward with the permitting process.

“Frankly, that doesn’t change the bottom line here,” said Ashley Rudzinski, Climate and Environment program director for the Groundwork Center. “We know that the state of Michigan still holds the power to stop this oil tunnel, so our state agencies really need to continue their rigorous review and ultimately reject this proposal.”

Environmental groups say they still have concerns about the project and analysis from the Army Corps, which was expedited under an order from president trump declaring an energy emergency.

“A project that’s going to take more than six years to construct is obviously not going to respond to an immediate emergency,” said Debbie Chizewer, managing attorney for Earthjustice’s Midwest office.

An updated report from the army corps will likely come later this year, with another public comment period before a final ruling.

“We’re anticipating that the agency will likely move forward with rubber stamping those permits, so that just puts even more of an onus on the state to be able to conduct a thorough review,” Rudzinski said.

The proposal will next be considered at the state level. EGLE, Michigan’s environmental agency, says they’re still considering two permits — one for pollutants and one for the impact on the lakes’ bottomlands.

Both processes will include a public comment period, which could be kicked off in the coming months.