Shovels aren't hitting the dirt anytime soon, despite what you might have heard about the latest federal green light for Enbridge's Line 5.
The U.S. Army Corps of Engineers just issued a long-awaited permit allowing Canadian energy company Enbridge to construct a four-mile-long concrete tunnel beneath the lakebed of the Straits of Mackinac. This tunnel is designed to house the contentious twin oil and natural gas pipelines. Supporters call it a critical upgrade for midwest energy security. Opponents view it as an environmental ticking time bomb.
If you think this federal decision settles the decade-long war over Line 5, you're missing the bigger picture. State courts, tribal sovereignty battles, and looming lawsuits mean this project is still stuck in deep legal mud.
What the Army Corps Actually Decided
After more than six years of review, the Detroit District of the Army Corps released a 54-page decision concluding that the tunnel construction complies with federal laws. Officials stated the project is not contrary to the public interest and does not violate tribal treaty rights.
Yet, the agency's own document acknowledges hard truths. The federal review admits the construction will cause permanent adverse effects on archaeological resources and the Straits of Mackinac Traditional Cultural Landscape. It points to long-term habitat loss and land use impacts.
Enbridge celebrated the decision as a rigorous validation of the project's safety. Company representatives maintain that enclosing the 645-mile pipeline—which runs from Superior, Wisconsin, to Sarnia, Ontario—inside a concrete tunnel deep beneath the lakebed removes the risk of an open-water anchor strike.
Why Construction Is Still Blocked
Getting a federal permit doesn't mean building can start tomorrow. Real-world roadblocks remain massive.
Just weeks before the Army Corps announcement, the Michigan Supreme Court handed Enbridge a major setback. The state's highest court vacated a previous approval from the Michigan Public Service Commission. Justices ruled that regulators failed to properly weigh environmental impacts under the Michigan Environmental Protection Act and ignored questions about whether the pipeline could operate safely without the new tunnel.
That means state regulators must re-evaluate the project from scratch. Until that state-level review clears, Enbridge legally cannot build.
The Tribal Sovereignty Battle
Money and engineering specs aren't the only friction points. Indigenous tribes have fought this project for years, viewing the latest federal approval as a betrayal.
Tribal leaders, including representatives from the Bay Mills Indian Community, point to the 1836 Treaty of Washington. Under this agreement, Ottawa and Chippewa nations ceded millions of acres of land in exchange for protected hunting, fishing, and gathering rights.
Critics argue the federal government trampled those treaty rights by fast-tracking the review under executive energy emergency directives. Legal teams representing environmental and indigenous coalitions have already promised new waves of lawsuits. Environmental law organizations like Earthjustice are doubling down on challenges to stop the construction zone from ever touching sacred Anishinaabe waters.
What Happens Next
If you're tracking energy infrastructure or Great Lakes protection, stop looking at federal permits as the final destination. The battleground has shifted entirely back to state courts and regulatory boards.
Expect months of renewed legal bickering in Michigan over the state-level public service commission remand. Enbridge faces an uphill climb to satisfy state environmental mandates while fending off coordinated federal lawsuits from tribal nations. The Line 5 tunnel is technically closer to reality today than it was last month, but the finish line remains years away.
