September 14, 2026.
Four Michigan Tribal Nations are challenging state permits for Enbridge's proposed Line 5 tunnel beneath the Straits of Mackinac, opening another legal front less than two months after the Michigan Supreme Court overturned a separate state approval for the project.
Bay Mills Indian Community, Little Traverse Bay Bands of Odawa Indians and the Sault Ste. Marie Tribe of Chippewa Indians filed a September 10 petition requesting a contested-case hearing before the Michigan Department of Environment, Great Lakes, and Energy (EGLE).
Grand Traverse Band of Ottawa and Chippewa Indians is also challenging the permits and is represented separately.
The challenges seek to overturn wetlands and bottomlands permits EGLE approved in July for construction of the proposed tunnel.
Supreme Court ruling changed the legal landscape.
The new challenges are separate from the case decided by the Michigan Supreme Court July 31.
That case concerned approval granted by the Michigan Public Service Commission, not the EGLE permits.
The four Tribal Nations involved in the Supreme Court litigation were Bay Mills Indian Community, Grand Traverse Band of Ottawa and Chippewa Indians, Little Traverse Bay Bands of Odawa Indians and Nottawaseppi Huron Band of the Potawatomi.
The Supreme Court vacated the PSC's approval and returned the case to the commission for additional proceedings.
Among the Court's findings was that the PSC improperly prevented development of evidence about whether construction of the tunnel could prolong Line 5's operation and therefore cause additional environmental consequences.
The Court also found problems with the PSC's analysis of alternatives and its consideration of public-trust resources.
EGLE had issued its separate resource permit July 15, only 16 days before the Supreme Court decision.
The Supreme Court did not order EGLE to redo that permit. Instead, its decision established legal findings that raised questions about whether EGLE's separate approval can withstand review under the same state environmental law.
On September 9, Gov. Gretchen Whitmer and EGLE Director Phil Roos announced that EGLE would examine what the Supreme Court ruling means for the permits the department had already approved.
Conditions on the EGLE permit currently prevent construction of the tunnel entrance from proceeding while those legal issues remain unresolved.
Tribal petition challenges EGLE's decision.
The petition filed by Bay Mills, Little Traverse Bay Bands and Sault Tribe argues that EGLE's decision violates Michigan environmental law and fails to adequately protect treaty-reserved rights, cultural resources and the Straits.
The Tribal Nations contend construction would permanently affect culturally significant areas and resources and that those losses cannot simply be addressed through mitigation requirements.
For Sault Tribe, the filing puts the Tribe directly into the current EGLE permit challenge.
The Tribe has separately opposed the tunnel through government-to-government consultation and public statements.
The Tribe has also stressed a fundamental sovereignty issue: government consultation does not constitute Tribal consent.
Line 5 supporters continue to back the tunnel.
Enbridge and numerous Michigan business, labor and energy organizations continue to support construction of the tunnel.
Supporters have included the Michigan Chamber of Commerce, Detroit Regional Chamber, Grand Rapids Chamber, Michigan Manufacturers Association, Michigan Laborers' District Council, Michigan Propane Gas Association, National Propane Gas Association and other organizations associated with the Great Lakes Michigan Jobs coalition.
The Michigan Laborers' District Council, Michigan Propane Gas Association and National Propane Gas Association formally intervened in the earlier PSC proceeding in support of the project.
Supporters argue that placing the pipeline inside a concrete-lined tunnel would protect it from anchor strikes and other hazards while preserving energy supplies and construction jobs.
Opponents argue that the tunnel would extend Line 5's operation for generations and that construction itself presents environmental, cultural and treaty-rights concerns that cannot be eliminated by putting the pipeline underground.
U.S.-Canada trade dispute adds uncertainty.
The legal fight is occurring as relations between the United States and Canada are becoming increasingly strained over trade.
Canada has historically treated Line 5 as an important part of its energy infrastructure and has invoked the 1977 Canada-U.S. Transit Pipelines Treaty in opposing efforts that could interrupt the movement of energy products across the border.
Neither Canada nor the United States has announced a change in its Line 5 position because of the current trade dispute.
But worsening relations raise a longer-term question: whether either country could eventually reconsider its dependence on cross-border energy infrastructure if the economic and political relationship continues to deteriorate.
For now, that remains a possibility rather than a government policy.
Multiple proceedings now determine the tunnel's future.
The legal situation surrounding the proposed tunnel is no longer one case.
The Michigan Public Service Commission must reconsider its approval following the Supreme Court's July 31 decision.
EGLE is examining the implications of that ruling for the permits it approved on July 15.
Bay Mills, Little Traverse Bay Bands and Sault Tribe have filed a contested-case petition challenging those EGLE permits, while Grand Traverse Band is pursuing its challenge through separate counsel.
Four environmental organizations — Environmental Law & Policy Center, Flow Water Advocates, Michigan Climate Action Network and National Wildlife Federation — have also filed a separate contested-case petition challenging the EGLE water-resource permit.
The disputes now put several fundamental questions before Michigan regulators: whether the tunnel satisfies Michigan environmental law, whether alternatives have been adequately considered, whether public-trust resources are protected and whether decisions affecting the Straits adequately account for Tribal Treaty Rights, Cultural Resources and Sovereignty.
This story is sponsored by Red Hawk a Native American Broadcasting Company Division.
