A Fast(er) Track for Line 5

Enbridge and environmentalists speak about updated timeline for the tunnel under the Straits of Mackinac

By Victor Skinner | May 17, 2025

The Canadian oil and gas company Enbridge in early March unveiled a revamped information center in St. Ignace that now features a 22-foot model of the boring machine the company plans to use to tunnel hundreds of feet below the Straits of Mackinac.

“There’s been a little bit of momentum and some new developments,” Enbridge spokesman Ryan Duffy says. “I know there’s been a lot of talk about fast-tracking, but whatever happens from here won’t be fast.”

“This has been going on for five years now,” he says, noting Enbridge submitted its permit application to the U.S. Army Corps of Engineers in 2020.

The May 7 open house at Enbridge’s information center in St. Ignace featured representatives from Barnard Construction Company and Civil and Building North America, who discussed the proposed 21-foot diameter, 3.6-mile Line 5 tunnel currently working its way through state and federal permitting processes.

A Truncated Process

The event followed just a couple of weeks after the U.S. Army Corps of Engineers announced plans to expedite its permitting process for the Line 5 tunnel, which is aimed at replacing two pipelines that carry 540,000 barrels of light crude and liquid natural gas from Canada 645 miles through the state every day.

The decision stems from an executive order signed by President Donald Trump on the first day of his second term declaring a national energy emergency to boost fossil fuel production. The order purports “the United States’ insufficient energy production, transportation, refining and generation constitutes an unusual and extraordinary threat to our Nation’s economy, national security and foreign policy.”

It calls for federal agencies to “identify and use all relevant lawful emergency and other authorities available to them to expedite the completion of all authorized and appropriated infrastructure, energy, environmental and natural resources projects that are within the identified authority of each of the Secretaries to perform or advance.”

The emergency designation allows the Corps to reduce the public comment period on an ongoing environmental impact assessment from 60 days to 30, though federal officials insist no decision will be made until all steps in the permitting process, including required consultations with the state’s indigenous tribes, are complete.

“We have full confidence that we will be making the decision based on the best information available,” Shane McCoy, regulatory chief for the Corps’ Detroit District, told reporters in mid-April. “The truncated process will result in a very legally defensible and very well-informed decision in our record of decision.”

An updated timeline shows the Corps will release its draft environmental impact statement on May 30, triggering a 30-day public comment period. The agency plans to prepare a final statement that will undergo a 30-day waiting period this fall, followed by a record of decision in “Fall 2025.”

Environmental Opposition

The shift to move to an expedited permitting process convinced the Native American Rights Fund (NARF) representing tribal interests to withdraw as a “participating agency” in that process in March, though NARF intends to submit objections during the public comment period. NARF attorney David Gover says that’s because tribal leaders “found that process unsatisfactory, flawed.”

“We didn’t want to give the impression we support the decision they are making,” he says. “They’re making their decision regardless of tribal input.”

NARF, Earthjustice, For Love of Water (FLOW), and other environmental groups have steadfastly opposed the project over concerns about the potential for a catastrophic disaster, such as the Enbridge oil spill in 2010 that released a million gallons into the Kalamazoo River.

NARF, working on behalf of the Bay Mills Indian Community, has also pointed to a potential impact on treaty rights and the tribe’s cultural traditions, both in court and through the state and federal permitting processes.

“Definitely this executive order [for] a national energy emergency has shifted the process,” Gover says. “I think the executive order itself needs to be reviewed closely.”

“The U.S. is producing more fossil fuels than ever before, while the administration is cutting back on wind and solar,” he adds.

Back to Court

NARF is also pushing back through other channels, such as government-to-government treaty talks, required cultural resources consultations under the National Historic Preservation Act, and legal challenges to permits issued by Michigan.

The Michigan Court of Appeals in February upheld a lower court order that found the Michigan Public Service Commission’s decision to permit the Line 5 tunnel in December 2023 included “no basis for ordering a reversal or remand.”

“The Commission acted reasonably when one considers its actions and rulings as a whole,” according to the three-judge panel.

NARF, FLOW, and others are now appealing that decision to the Michigan Supreme Court, arguing the MPSC excluded critical evidence in its decision regarding climate change impacts and viable alternatives to transporting Enbridge’s oil and gas that doesn’t involve the tunnel.

“The court of appeals argued in a nutshell that the [MPSC] is not subject to common trust law,” FLOW Executive Director Liz Kirkwood says, noting the law requires the protection of public waters. “That’s incorrect, so we are appealing that to the Michigan Supreme Court.”

The court of appeals also “failed to review [the MPSC approval] de novo—with their own eyes—so we’re challenging that, as well,” she says.

Permitting Plans

The Army Corps and MPSC permits represent two of the three Enbridge needs to forge ahead with the tunnel, while the Michigan Department of Energy, Great Lakes and Environment issued the third set of permits in 2021.

The EGLE permits are set to expire in early 2026, and Enbridge is now working to submit fresh documentation to renew, Duffy says.

“We have applied to renew those EGLE permits … and that’s a process that could take months,” he says. “Given EGLE did approve already in 2021, we think it will be a similar process and we’re going to follow their timeline on that.”

“Nothing has really changed substantially,” he explains. “We have some additional better information on things since we’ve done more survey work.”

FLOW and other opponents argue the renewal “requires a full and brand-new review of the impact to the wetlands,” Kirkwood says.

Pending Cases

Enbridge also faces multiple court cases in Michigan and Wisconsin that could impact if or when tunnel construction begins. Those cases include Nessel v. Enbridge in state court, in which Michigan Attorney General Dana Nessel is working to shut down the pipeline, as well as Enbridge v. Whitmer, a lawsuit brought by Enbridge that argues the former is moot.

“We have urged the federal court in Enbridge v. Whitmer to determine that the State cannot take any action to interfere with Line 5’s operation, and that ruling should apply equally to the Attorney General’s complaint,” Duffy wrote in an email.

In Wisconsin, another ongoing case centers on Enbridge’s effort to re-route Line 5 around a reservation owned by the Bad River Band of Lake Superior Chippewa. The tribe and environmental groups are contesting a decision from the Wisconsin Department of Natural Resources to permit the 41-mile re-route, setting up hearings before an administrative law judge that have yet to commence.

The Wisconsin case is expected to face an appeal regardless of the decision, suggesting that case could eventually end up in Wisconsin Supreme Court.

In both Michigan and Wisconsin, the high courts hold a liberal majority political observers believe will be sympathetic to tribal and environmental interests.

More to Say

While the permitting and legal challenges slog along, both Enbridge and its opponents continue to make their case to the public.

“Why would the federal government and state government of Michigan allow this tunnel to be built when this pipeline, which is about to be 72 years old this month … is a pipeline that transports Canadian oil through the pipeline back to Canada?” Kirkwood says, adding FLOW is also concerned about the potential for an explosion during construction that would devastate one of the largest sources of freshwater in the world.

“It’s deeply concerning to see the federal government try to circumvent federal law,” Kirkwood concludes. “It really makes no sense to fast track this project when there’s so many question marks.”

In St. Ignace, Enbridge’s revamped information center, open 9 am to 5 pm on weekdays, is “a big piece” of the company’s efforts to convince the public about the safety of Line 5 and the tunnel.
It includes information about the company’s Straits Monitoring Center, which is staffed by an operator 24/7 to monitor seven cameras on the lake bed and provide electronic alerts to passing ships.

The new information center also highlights more than 40,000 hours of survey work since 2018, offers an up-close look at the boring model, and offers facts about Line 5 itself, which provides more than half of the state’s propane, jet fuel for Michigan airports, and materials for manufacturing more than 6,000 consumer products in the state, according to Duffy.

In addition, Enbridge is pointing to its tunnel contractors’ track record for safety, noting the companies have built more than 100 tunnels in 15 countries equating to 370 miles under places like downtown San Francisco and the Port of Miami.

“Some of the projects had similar geological conditions to the conditions at the straits,” Duffy says. “They’ve done tunnels of all sizes, including bigger than this one we will be doing.”

So far, more than 33 Michigan counties have passed resolutions in support of the tunnel project, he says, including “all the [Upper Peninsula] counties and most of the counties on the route of Line 5 down through the state.”

“As we proceed with this modernization project, we remain committed to operating Line 5 responsibly with enhanced safety measures in the Straits that protect Michigan’s natural resources and infrastructure,” Duffy wrote in an email.

Photo Courtesy of FLOW