I've been worried that #5, which runs under the Mackinac Bridge and the Straits of Mackinac will leak and create an environmental disaster in this very sensitive ecosystem.

From the Native American Rights Fund:

Enbridge continues to operate the Line 5 pipeline in defiance of a state order to cease operations and without a valid lease to submerged lands for the project. A repeat offender of U.S. environmental regulations, the Canadian oil company has incurred over $6.5 million in fines to repair and maintain existing Line 5 infrastructure. You don’t have to look far to see the potential impact a devastating oil spill can cause, in fact, Enbridge was responsible for the largest inland oil spill in 2010 in Michigan’s Kalamazoo River, which resulted in nearly 1 million gallons of oil being released into Michigan’s waterways.

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On July 7, 2022, Michigan Public Service Commission requested additional information concerning the safety risks posed by the Enbridge Line 5 pipeline segment in the Straits of Mackinac, and its proposed tunnel replacement. The Commission’s order followed frontline tribal nations stressed that continuing to operate Line 5 jeopardizes the health, safety, and livelihoods of Indigenous communities native to the Great Lakes Basin. Pipeline safety expert Richard Kuprewicz also underscored to the Commission the increased likelihood of an explosion in the Straits when transporting crude oil through a tunnel, which would have catastrophic impacts to water supply, wildlife, and air quality.

“Any decision that may jeopardize the very livelihoods of Tribal Nations deserves serious and careful consideration,” said Bay Mills Indian Community President Whitney Gravelle. “We are grateful the Commission is examining the serious safety risks posed by Line 5 and its proposed tunnel replacement. The Straits are the center of creation for our people, and the construction of a tunnel through this sacred area endangers our livelihoods, our fisheries, and our culture. Every day that the Line 5 dual pipelines continue to pump oil and gas through the Great Lakes amounts to a violation of our treaty-protected rights and an acceleration of climate change. We must stop the tunnel project and shut down Line 5.”

NARF Staff Attorney David L. Gover agreed. “It is reassuring to know that the Commission is doing its due diligence in order to accurately consider the impacts, risks, and damages the existing Line 5 oil pipeline and a tunnel would cause for the public, in particular tribal citizens”, said Gover. “I am hopeful that the Commission will join tribal and state governments in guarding public safety, the local economy, and the Great Lakes ecosystem from a risky and unnecessary project.”

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More here

It seems like anytime there is a spill (major/minor doesn't matter) they send out their troop of "government relations managers" to speak at county board meetings, city council meetings, township meetings to tell us ALL IS WELL!

This exact pipeline and how dangerous it is. Maybe the oil companies are trying to figure out how to get gas prices back up to that profitable sweet spot again.