Gretchen Whitmer, a Democrat, is governor of Michigan.

Oil and water don’t mix — especially when the latter involves the Great Lakes, the repository of more than 20 percent of the world’s fresh water. And yet for nearly 70 years, an oil company has pumped crude oil through the Straits of Mackinac, where Lake Michigan and Lake Huron connect and where Michigan’s upper and lower peninsulas come closest.

The two aging, 4.5-mile sections of underwater pipeline are a ticking time bomb. I’m taking every action I can to shut them down, to protect two Great Lakes and the jobs that depend on them.

Calgary-based Enbridge Inc. owns the pipeline, known as Line 5, which is part of a network that transports crude oil and other petroleum products from Western Canada. In 1953, a forerunner Enbridge company secured an easement from the state of Michigan for $2,450 to run the pipeline through the Straits. It now moves about 540,000 barrels of crude and natural gas liquids through the Great Lakes daily.

For decades, few people even realized that the dual pipelines passed through the Straits. But catastrophic oil spills have since alerted millions of Americans to the enormous potential dangers. In Michigan, the turning point might have been in 2010. In April of that year, the deadly disaster of the BP Deepwater Horizon drilling rig poured millions of barrels of oil into the Gulf of Mexico; three months later, an Enbridge pipeline in Michigan, Line 6B, ruptured, sending hundreds of thousands of gallons of oil gushing into a creek feeding the Kalamazoo River, near Marshall, Mich. It was one of the largest inland oil spills in U.S. history.

After those twin catastrophes, eyes turned to the aging oil pipelines running through the Great Lakes.

While Enbridge says its pipelines pose no threat, the record from just the past few years says otherwise. The Straits of Mackinac is a busy shipping channel, with the dual pipelines lying perpendicular to passing ships. In April 2018, a commercial vessel inadvertently dropped and dragged a massive anchor across the pipelines while passing through the Straits. An “underwater pipeline inspection video shows deep scoring along the lake bottom, then up and over the twin pipelines,” the Detroit Free Press later reported. “Deep marks are etched in both pipelines, and there is evidence of outer protective coating loss.”

It was just a matter of luck that the pipelines did not rupture. Then, in 2020, Enbridge disclosed another strike on Line 5, one that caused significant damage to a pipeline support, likely by either an anchor or cables from a passing ship. Another catastrophe dodged.

The potential costs of a major oil spill are too great to ignore. The Great Lakes support more than 1.3 million jobs that generate $82 billion in wages annually across the United States. We cannot continue to run the risk of the devastating economic, environmental and public health impacts that would follow a disaster involving Line 5.

That’s why I took action. Last November, I filed a lawsuit and notified Enbridge that the state of Michigan was revoking and terminating the 1953 easement for Enbridge’s dual pipelines in the Straits. The notice gave Enbridge 180 days — until this past Wednesday — to cease pumping oil through the Great Lakes. This week, I notified Enbridge that if it continues to operate past the deadline — which it has done — the state would make every effort to disgorge the company of all profits unjustly earned from Line 5 while trespassing on state land.

Enbridge says it will continue pumping until a court orders it to stop. I’m confident the state will prevail. Even under federal law, states retained the right to prescribe the location of pipelines. The company may end up running a new pipeline elsewhere: Although it would be years away at best, Enbridge is exploring the possibility of digging a tunnel under the Straits of Mackinac. The authority is 49 U.S.C. 60104(e).

But at this moment, the company must stop pumping oil across the bottomlands of the Great Lakes. Enbridge is flat wrong in its absurd argument that Michigan, having said yes in the 1950s, cannot say no today. That’s why 16 other states and D.C. have filed an amicus brief supporting my position: to preserve their sovereign rights over where pipelines are laid.

Shutting down Line 5 will require adjustments, which are already underway. For example, Michigan draws propane from the pipeline. Anticipating the coming changes, the market for Michigan’s wholesale propane supply is diversifying and propane retailers are developing alternative sourcing arrangements. The state is also taking steps to prevent price gouging and exploring opportunities to invest in renewable energy, energy efficiency and electrification to bring down long-term costs.

Running pipelines through the water of the Great Lakes is, and always has been, a dangerous threat. I will not sit idle as this time bomb keeps ticking.

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