Army Corps extends environmental review of Michigan pipeline tunnel

The U.S. Army Corps of Engineers has extended its timeline for a decision on a proposed Great Lakes oil pipeline tunnel opposed by Native groups and Michigan Gov. Gretchen Whitmer (D).

The Detroit District of the Corps said Thursday its environmental review of the Enbridge Energy project will take an additional 18 months, after thousands of public comments poured in about the project.

The proposed tunnel, known as Line 5, would run beneath the Straits of Mackinac, which link Lakes Huron and Michigan. Whitmer has called the tunnel a “ticking time bomb” over concerns it could leak and pointed to what she labeled Enbridge’s “troubling” safety record, citing a 2010 pipeline rupture that was the largest inland oil spill in U.S. history.

The Bay Mills Indian Community has also vocally opposed the project, retaining the Native American Rights Fund (NARF) and Earthjustice to represent it in the review process. 

“The area remains integral to daily practice of cultural lifeways and is full of historic and archaeological sites. From time immemorial to today, communities, local businesses, and tribal members depend on the abundant fish and wildlife in the Straits of Mackinac,” NARF said in a statement. “Commercial and subsistence fishing and hunting continue to provide economic survival for the majority of tribal members.” 

The state sued Enbridge in 2020 but dropped the suit to focus on a state lawsuit the next year. Last year, a judge moved the state suit to federal court as well, siding with Enbridge.

The Army Corps of Engineers’ review was previously set to finish by late this year. It will now be issued no earlier than spring 2025, with a final approval decision in early 2026. 

Detroit District Commander Lt. Col. Brett Boyle said the district received more than 17,000 public comments ahead of the decision to push back its timeline. 

“While we are supportive of a thorough, comprehensive and carefully considered permitting process that ensures adequate opportunity for review and comment, we are disappointed with the extended timeline for a project of this scope,” Enbridge said in a statement.

“The Great Lakes Tunnel Project covers only approximately four miles in length, will require no construction within the waters of the Straits, and is anticipated to impact less than one-quarter acre of wetlands,” it added.