Michigan appeals court upholds permits for Line 5 tunnel project

Enbridge wants to build a protective tunnel around a section of its Line 5 pipeline that runs along the bottom of the Straits of Mackinac, which link Lake Michigan and Lake Huron.

Enbridge’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 Indigenous groups that commissioners failed to consider the overall need for the pipeline.

Enbridge wants to build a protective tunnel around a six-kilometre 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, Wis., and Sarnia, Ont.

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.

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.

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.