Michigan appeals court upholds permits for Great Lakes pipeline tunnel project

MICHIGAN—Enbridge Energy’s plans to build a protective tunnel around an aging pipeline that runs beneath a channel connecting two Great Lakes can continue, a Michigan appeals court ruled.

The state Public Service Commission properly issued permits for the $500 million project, the Michigan Court of Appeals ruled Wednesday in rejecting arguments from environmental groups and Native American tribes that commissioners failed to consider the overall need for the pipeline.

Tunnel would encase pipeline in the Straits of Mackinac

Enbridge wants to build a protective tunnel around a 4-mile (6-kilometer) section of its Line 5 pipeline that runs along the bottom of the Straits of Mackinac, which link Lake Michigan and Lake Huron. Enbridge has been using the pipeline since 1953 to transport crude oil and natural gas liquids between Superior, Wisconsin, and Sarnia, Ontario.

Concerns about a potentially catastrophic spill in the straits have been building since 2017, when Enbridge officials revealed that engineers had known about gaps in the pipeline’s coating in the straits since 2014. Fears of a spill escalated in 2018 when a boat anchor damaged the line.

Enbridge officials maintain that the line is structurally sound, but they still reached an agreement with then-Michigan Gov. Rick Snyder’s administration in 2018 that calls for the company to build the protective tunnel.

Environmental groups, tribes challenge state permits

The Michigan Public Service Commission issued state permits for the project in December 2023. Environmental groups including the Michigan Environmental Council and the National Wildlife Federation, along with the Little Traverse Bay Bands of Odawa Indians, Bay Mills Indian Community, Grand Traverse Band of Ottawa and Chippewa Indians, and the Nottawseppi Huron band of the Potawatomi asked the appellate court last year to reverse the commission’s decision.

The groups and the tribes alleged that the commission improperly considered only the public need for the tunnel rather than whether the entire pipeline as a whole is still necessary. They also argued the commission failed to adequately consider petroleum products’ greenhouse gas impacts.

Court: Commission acted reasonably

The appellate court found that the commission issued a “comprehensive” opinion and acted reasonably. It said there was no basis for a reversal or to order the commission to revisit its decision.

David Scott, a senior attorney for the Environmental Law & Policy Center and the Michigan Climate Action Network, which are also plaintiffs in the case, said in an email that he was disappointed with the ruling and considering further moves. He didn’t elaborate.

Environmental law firm Earthjustice represented the tribes in the case. Adam Ratchenski, an attorney with the firm, said that regardless of the appellate ruling, it was “backwards and dangerous” for the commission to approve the tunnel without truly considering whether Michigan residents need it.

“Nobody wants their water poisoned or their property values torpedoed in order to keep Canadian oil and gas flowing through the Great Lakes,” he said.

Enbridge spokesperson Ryan Duffy praised the appellate ruling, saying the tunnel will make a safe pipeline even safer.

The legal fight isn’t over

The ruling Wednesday doesn’t end the legal battle over the tunnel. Current Michigan Gov. Gretchen Whitmer, a Democrat, opposes the continued operation of Line 5 even if it’s encased in a tunnel. Democratic Attorney General Dana Nessel filed a lawsuit in 2019 seeking to void the easement that allows the line to run beneath the straits. That case is pending in state court in Ingham County. A ruling could come any day.

Enbridge would still need a permit from the Michigan Department of Environment, Great Lakes and Energy as well as federal construction permits from the US Army Corps of Engineers before construction could begin. Environmentalists fear that President Donald Trump’s administration will fast-track that process after Trump declared a national energy emergency on his first day in office.

READ MORE: Anti-Line 5 coalition raises alarms as tunnel project is placed on emergency permitting list