Michigan Public Service Commission approves Great Lakes Tunnel application

Animated image of a tunnel boring machine

Decision advances safety-focused Enbridge project in Straits of Mackinac

Dec. 1, 2023

Today the MPSC approved a critical permit necessary to build the Great Lakes Tunnel in the Straits of Mackinac.

By a 2-0 vote, the MPSC ruled that Enbridge could install a new 30-inch diameter pipeline segment into the planned Great Lakes Tunnel. Once installed, the existing dual pipelines would be deactivated. The Great Lakes Tunnel would keep energy flowing safely to Michiganders while reducing to zero the chance of a release into the waterways.

More than 50% of northern Michigan relies on propane that comes from the natural gas liquids transported by Line 5. Similarly, more than 70 percent of Michiganders support construction of the Tunnel.

“The decision by the MPSC is a major step forward in making the Great Lakes Tunnel Project a reality, securing the vital energy people in Michigan and surrounding region rely on every day,” said Mike Fernandez, Enbridge’s senior vice president of public affairs, communications and sustainability.

“The permit from the MPSC is key to building this engineering marvel and continuing to deliver to Michiganders the energy on which they have come to depend on from Line 5.”

Great Lakes Tunnel at a glance:

The tunnel would house Line 5 below the Straits and also have potential to house other important utilities, such as high-speed fiber optic cables to improve emergency services and internet service in the Upper Peninsula
The tunnel would be approximately 21-feet in diameter
The tunnel will be monitored 24/7
Enbridge, not Michigan residents, would pay for Great Lakes Tunnel

“It’s time to build the tunnel so that we can protect the waters of the Great Lakes, the environment, the people who use the precious waters, while keeping energy flowing to this region,” said Fernandez.

“The tunnel is really a win-win solution for Michiganders and the region.”

The MSPSC decision comes after almost four years of public input and review and is the last decision Enbridge requires from the State pertaining to the replacement section of Line 5.

Enbridge is awaiting publication of the Draft Environmental Impact Statement from the U.S. Army Corps of Engineers before it can begin construction on the tunnel.