U.S. Army engineers expedite permits for controversial Great Lakes pipeline tunnel project

The U.S. Army Corps of Engineers announced it will expedite permits to build a tunnel around an aging oil pipeline that runs beneath the Straits of Mackinac. This channel connects Lake Michigan and Lake Huron. For years, the pipeline’s continued operation has troubled environmentalists and Native American tribes over concerns about the potential for an oil spill and the perpetuated use of fossil fuels.

The move comes three months after President Donald Trump signed an executive order declaring a “national emergency” over what he called the United States’ “inadequate development of domestic energy resources.” The order calls on federal agencies to identify energy infrastructure projects for expedited energy permitting from the Corps of Engineers and the Environmental Protection Agency (EPA).

The Army Corps designated the tunnel project for the Line 5 oil pipeline as an emergency under the order on April 15.

Line 5 is a 72-year-old pipeline that runs 645 miles from Superior, Wisconsin, through Michigan’s Upper Peninsula, across the Straits of Mackinac, and through the Lower Peninsula to Sarnia, Ontario. The pipeline is owned and operated by Enbridge, a Canadian energy corporation.

Environmentalists and Native American tribes have considered the aging pipeline an existential threat for years. In 2014, a researcher from the University of Michigan identified the Straits of Mackinac as the “worst possible place for an oil spill in the Great Lakes,” as currents would quickly contaminate shorelines miles away in both lakes Michigan and Huron in the event of an oil spill.

Enbridge’s history doesn’t exactly ease concerns. In March 1991, the company’s Line 3 pipeline ruptured near Grand Rapids, Minnesota, spilling 1.7 million gallons of crude oil, the worst inland oil spill in U.S. history. In July 2010, Enbridge’s Line 6B pipeline ruptured near Marshall, Michigan, and leaked more than 843,000 gallons of crude oil into the Kalamazoo River. Last year, Enbridge’s Line 6 pipeline leaked 69,000 gallons of oil in Wisconsin.

Across the pipeline, Line 5 has leaked at least 1.13 million gallons of oil in 29 separate incidents from 1968 to 2017, according to data from the National Wildlife Federation.

Concerns over an oil spill at the Straits of Mackinac escalated in April 2018 after a 12,000-pound anchor damaged the line. That same year, Enbridge reached an agreement with then-Michigan Governor Rick Snyder to bore a tunnel under the channel to house the pipeline. Initial cost estimates for the Great Lakes Tunnel Project were set at $500 million.

In December 2023, the ​​Michigan Public Service Commission approved a permit for the tunnel project. After this, the only remaining obstacle was approval from the U.S. Army Corps of Engineers, which at the time was expected to make a permit decision in 2026 after conducting a review of the project’s potential environmental impact.

After the recent announcement by the Corps, Enbridge spokesperson Ryan Duffy said Line 5 is “critical energy infrastructure” and the tunnel project will “make a safe pipeline safer.”

Despite Enbridge’s assertions, some engineers and pipeline safety experts have previously expressed alarm over the tunnel project.

Transporting propane and crude oil involves hazardous, volatile substances that bear the risk of explosion. Brian O’Mara, the founder of Agate Harbor Advisors LLC, has identified multiple scenarios in which an explosion could occur. This includes the risk that highly explosive dissolved methane could enter the tunnel during the boring process; the risk that groundwater containing methane could enter the tunnel after construction; and the risk of an explosion if crude oil is leaked from Line 5.

In such a scenario, a single spark could cause the pipeline to explode, O’Mara said. In a 2024 opinion article in the Detroit Free Press, O’Mara was quoted as saying, “the spark generated between a person’s finger and doorknob after walking across carpeting on a dry day produces significantly more energy than required to ignite a methane/air explosion.”

Trump’s executive order, which declares a “national energy emergency,” is seen by environmental activist Marc Brodine as an escalation of prior “excuses” for anti-environmental policies.

Brodine, the author of the book Green Strategy, said that while right-wing politicians in the past would push the “false dichotomy” of needing to “choose between jobs or the environment,” Trump instead frames the issue in terms of national security.

“What Trump is doing is saying ‘Oh I have this handy new excuse that everything is an emergency, therefore I have emergency powers and I can just declare that we should start digging up more beautiful, clean coal,’ as he likes to say,” Brodine said. “He’s a con man. He’s a salesman and he knows that without escalating their rhetoric, as ridiculous as some of it is, they won’t get the emergency powers that he so much desires.”

“Their old excuses haven’t been working so well; the denialism of 30 years ago, the ‘Let’s balance economics and jobs and environment’ of 20 years ago,” Brodine said. “Now it’s, ‘Oh, this is a giant national security crisis, therefore I get to have emergency powers.’ Therefore, ‘I get to decide on my own without that pesky democracy of laws and regulations.’”

“The reality is there is no energy crisis,” Brodine said. “There is no emergency that justifies any of this.”

Brodine’s sentiment that there is no energy crisis, as Trump claims, is shared by environmentalist groups such as the Sierra Club.

“The only energy ‘emergency’ the American people face is Trump’s efforts to disregard clean air and water safeguards in order to rush through dirty, dangerous fossil fuel projects,” said Mahyar Sorour, the director of the Sierra Club’s Beyond Fossil Fuels Policy, in a statement.

“The United States is already the largest oil producer and gas exporter in the world, yet Trump and his cabinet want to help corporate polluters rake in more profits while we suffer the very real public health and economic consequences,” Sorour said. “Instead of circumventing legally required reviews intended to protect communities, the truly patriotic thing to do would be to invest in clean, affordable energy.”

Others, such as Sean McBrearty with the organization Oil & Water Don’t Mix, described the recent announcement as a “sham” and said they are “simply taking orders” from the Trump administration.

“Let’s call this decision out for what it is: a sham,” McBrearty said in a statement. “By avoiding looking at the impact the Line 5 tunnel would have on the Great Lakes that families, industries, and Indigenous peoples rely on, the Army Corps is simply taking orders to not do their job and avoid looking at the actual problems with building this monster.”

“We need full permitting for the Line 5 tunnel project, which means thoroughly vetting its environmental, economic, and social impacts,” McBrearty said. “Anything short of that would be giving Enbridge—a corporation with a dangerous track record operating in Michigan—a blank check for a project that has no business getting built.”

Native American tribes have also had a contentious history with Enbridge.

In June 2023, a federal judge ordered Enbridge to shut down a portion of Line 5 in Wisconsin that crosses the land of the Bad River Band of Lake Superior Chippewa. The judge gave Enbridge a three-year timeline to reroute the line off the Band’s land, as well as pay the Band more than $5.15 million for trespassing.

Enbridge appealed the decision, and then-President Joe Biden’s administration said the judge’s ruling “failed to adequately assess” treaty obligations between the U.S. and Canada. Native American tribes consider ejecting Enbridge from the Bad River Band’s reservation as important to their sovereignty, and many are concerned about PFAS and mercury contamination.

In 2023, the United Nations Permanent Forum on Indigenous Rights called on Canada to “re-examine its support” for Line 5, saying the pipeline “presents a real and credible threat to the treaty-protected fishing rights of Indigenous Peoples in the United States and Canada.” The forum has recommended that the U.S. and Canada decommission the pipeline.

Multiple Native American tribes withdrew from federal discussions over Line 5 in March, saying the anticipated permit for the tunnel project is “unacceptable.”

Earlier this month, Native American tribes and environmental groups asked the Supreme Court to consider overturning a lower court’s decision to uphold the Michigan Public Service Commission’s permit for the tunnel project.

“Even if the public has been misled into believing this tunnel project is safe, the truth is that it is not,” said Bay Mills Indian Community President Whitney Gravelle in a statement. “Enbridge’s track record speaks for itself—catastrophic spills, environmental destruction, and a complete disregard for tribal sovereignty and the rights of future generations.”

“The Straits of Mackinac are not just a waterway; they are the heart of creation for Anishinaabe people and a vital source of life for all who depend on the Great Lakes. An oil spill here would be devastating, not only to our way of life but to the entire region,” President Gravelle said. “This fight is about more than just one pipeline—it’s about protecting our waters, our treaties, and our future. We cannot allow corporate interests to dictate the fate of the Great Lakes for another century.”