Climate scientists argue Line 5 tunnel would emit harmful emissions

Leonard N. Fleming
The Detroit News

Climate scientists on behalf of environmental groups and Native Americantribes opposed to a controversial tunnel for Line 5 in the Straits of Mackinac are contending the construction would emit "excessive greenhouse gas emissions" harmful to the climate, according to documents filed with the state.

The Environmental Law & Policy Center and the Michigan Climate Action Network filed written testimony from these experts with the Michigan Public Service Commission, which is reviewing whether to approve a permit for the $500 million project proposed by Enbridge Energy.

Both groups say they were allowed last spring to present expert witnesses to show how the climate is impacted by Line 5 as part of a meaningful environmental review of the permit request before the commission.

Enbridge's Mackinaw Station for Line 5. Climate scientists on behalf of environmental groups and Native American tribes opposed to a controversial tunnel for Line 5 in the Straits of Mackinac are contending the construction would emit "excessive greenhouse gas emissions" harmful to the climate, according to documents filed with the state.

Peter Erickson, a greenhouse gas emissions expert and senior scientist at the Stockholm Environment Institute affiliated with Tufts University, said in his testimony that "when compared to a scenario in which the existing Line 5 pipeline no longer operates, construction and operation of the proposed project would lead to an increase of about 27 million metric tons CO2e annually in global greenhouse gas emissions from the production and combustion of oil."

Another expert, Peter Howard, the economics director at the Institute for Policy Integrity at New York University School of Law, said from 2027 to 2070 the average annual climate costs would approximate $1 billion each year over this period, "plus significant unmonetized climate effects and other unquantified pollution costs to human health and the environment."

"The solution to the risk of an oil spill in the Great Lakes is simple: stop operating the existing pipelines," said Margrethe Kearney, senior attorney at the Environmental Law & Policy Center. "The question of what Enbridge can and should do once the existing lines shut down is a separate question, and it is clear that construction of a tunnel under the Straits is not the answer, because it will have a devastating impact on Michigan’s natural resources by contributing to the climate crisis.”  

Enbridge defended its proposed tunnel as environmentally safe and even cited testimony filed by commission staff that gave support to the soundness of the project.

“Staff concludes that the replacement of the dual pipelines with a new pipeline in a tunnel below the lakebed serves a public need, is in the public interest, and is the best option” from the other alternatives, according to Travis Warner, a public utility engineer specialist with the commission.

Enbridge said commission staff found no "concerns with the safety of the replacement segment of the pipeline" in the tunnel and that "transportation alternatives to a pipeline would emit approximately 160% more greenhouse gases than pipeline transportation."

"Placing a pipeline in a new Great Lakes Tunnel will provide extra layers of safety and environmental protection and make what is currently a safe pipeline even safer, while creating Michigan jobs and securing the needed energy for consumers in Michigan and the region," said Ryan Duffy, Enbridge's spokesman.

The company said it completed its engineering and design phase of the 4-mile tunnel that will house the pipeline in March.

Gov. Gretchen Whitmer ordered Line 5 closed by mid-May given the risks of an oil leak into the Straits of Mackinac that environmentalists, Native American tribes and water experts say would have severe consequences long term for the Great Lakes.

Enbridge has refused to shut down Line 5 unless ordered by a judge and filed suit in federal district court where the Canadian oil conglomerate argued federal regulators and not state officials have the last say on what happens to the line.

"These experts confirm that Line 5 is a huge contributor to the climate crisis, and building an oil tunnel would cause billions of dollars more of worsening climate impacts for years to come," said Kate Madigan, the Michigan Climate Action Network director. "Building an oil tunnel works against the goals of the Paris Agreement and Michigan’s Healthy Climate Plan. If we are serious about those goals, and avoiding the worst impacts of climate change, the only reasonable way forward is to shut down Line 5 and not build a new oil tunnel."

lfleming@detroitnews.com

Twitter:@leonardnfleming