Coast Guard investigates whether vessel activity may be causing Line 5 damage

Apr 13, 2018

The Mackinac Bridge in March 2018
Credit Aaron Selbig

CORRECTION 4/13: A previous version of this story incorrectly stated that the U.S. Coast Guard said damage to an electric transmission line under the Straits of Mackinac may have been caused by an "anchor strike." The Coast Guard says the leak may have been caused by "damage from vessel activity."

Governor Rick Snyder is asking Enbridge Energy to accelerate it’s decommissioning of the Line 5 pipeline under the Straits of Mackinac.

The request comes following a report from the U.S. Coast Guard that says damage from vessel activity may have caused an electric transmission line to leak synthetic fluid.

Line 5 and the underwater electric cables are in the same vicinity. Coast Guard officials say vessel activity may be the cause of three dents to Line 5.

Mike Shriberg is the Great Lakes Regional Director for the National Wildlife Federation. He says state officials didn’t listen to risk analysts.

“An anchor strike was actually listed as the most likely cause of a leak in Line 5, although the consultants for the State said it was a remote possibility," says Shriberg. "Well the remote possibility just struck three times. We have three dents in line 5.”

Shriberg says none of the six electric transmission lines, the natural gas pipe or Line 5, under the Straits, have substantial protective coverings.

Officials with Enbridge Energy, which owns the 65-year- old Line 5, say the pipeline remains safe despite the newly discovered dents. The company released a statement saying that it has confirmed dents to both segments of the twin pipeline. The statement says the structural integrity of the pipeline “has not been compromised.”

State Sen. Wayne Schmidt (R-Traverse City) released a statement Thursday night calling for the shutdown of the pipeline while an independent risk analysis is done. 

“I cannot begin to explain my disappointment with what happened last week — not only because of what happened, but how it was handled as well,” said Schmidt. “The communication efforts by Enbridge and ATC (American Transmission Company) were nonexistent.”

“The line should remain down as we independently verify that there is no potential for risk — including shipping or anchor damage — or come up with an alternative,” Schmidt said. “Taking Enbridge at their word that everything is operating as it should is not good enough. There is simply too much conflict and too great a risk to our state’s natural resources.

Interlochen Public Radio and WCMU Public Radio contributed to this report.