The plan to dig a nearly four-mile tunnel underneath the Straits of Mackinac and replace the Line 5 oil and gas pipelines continues to move forward.
Last week, Michigan’s Department of Environment, Great Lakes, and Energy said the plan complies with environmental laws on wetland protection, cultural resources, and wastewater discharge.
But other state and federal agencies still need to weigh in on the project. And one big sticking point is climate change and whether carbon emissions from burning the oil and gas that flow through Line 5 should be a factor in deciding if the tunnel project gets greenlit.
That question is before a Michigan judge right now, and could ultimately determine the tunnel’s fate.
Why does climate matter for a pipeline?
For most energy projects that are proposed on public lands, like drilling for oil and gas or installing a solar farm, the government has to review the resulting environmental impacts, including greenhouse gas emissions.
That’s true for pipelines too, explains Pete Erickson, who studies climate policy at the Stockholm Environment Institute.
“There is a clear causal link between a pipeline being built or not built and both the production and consumption of that oil, and therefore carbon dioxide emissions, and therefore climate change,” he says.
And a project’s impact on climate can be the deciding factor in whether or not it goes forward. A high-profile example is the Keystone XL Pipeline, which would have carried oil and gas from Alberta to Nebraska. The main reason the federal government didn’t grant a permit for the project was because of climate change, according to the Obama administration.
And there have been other examples, like recently in Washington, where state agencies have rejected fossil fuel projects because of their projected carbon emissions.
What’s different about Line 5
For the Line 5 tunnel project, Enbridge, the company behind the proposal, requested that government agencies make an exception in this case.
That’s because the company argued this is not a new pipeline — it would just replace the old one and make it safer.
Enbridge made their case to Administrative Law Judge Dennis Mack.
“He’s kind of the gatekeeper,” explains Margrethe Kearney, an attorney at the Environmental Law & Policy Center in Chicago.
“Here, Enbridge asked [the judge] to exclude any evidence that relates to greenhouse gas emissions or to climate change.”
And Judge Mack agreed with Enbridge. Back in October, he said public agencies should not consider greenhouse gas emissions with this tunnel project at all.
Greenhouse gas emissions reconsidered
Then there was this seismic shift in the equation: In November, Governor Gretchen Whitmer ordered the shut down of Line 5. She gave Enbridge a deadline of May to stop the flow of oil and gas through the Straits.
Whether the order will stand is playing out in court right now, but it’s already impacted the tunnel project.
Before the Governor’s shutdown, Enbridge was basically saying we’re going to run this pipeline one way or another, Kearney says. “That narrative goes away if they are no longer able to run the pipeline along the bottom of the Straits of Mackinac.”
If the shutdown goes forward, approving the tunnel project is no longer a choice between running the pipeline at the bottom of the Straits or running the pipeline in a tunnel. “The choice is ‘Are we not going to run the pipeline, or are you going to let us build a tunnel so we can run the pipeline?’” Kearney says.
In a statement shared with IPR, an Enbridge representative said considering climate change impacts are “extraneous issues” and “outside the scope of the proceeding.”
Ultimately, it’s up to the U.S. Army Corp of Engineers and the Michigan Public Service Commission to decide whether Enbridge should be able to build their Line 5 tunnel.
And maybe when they make their decision, they’ll weigh the impacts of carbon emissions from the project too.