Whitmer: Line 5 shut down after 'significant damage' to anchor support

Craig Mauger
The Detroit News

Lansing — Michigan Gov. Gretchen Whitmer revealed Friday that Enbridge had shut down Line 5 in the Straits of Mackinac after an anchor support sustained "significant damage" from an "unknown" cause.

In a letter to Enbridge CEO Al Monaco, Whitmer detailed the situation, saying Enbridge informed the state of the damage to the anchor support on Thursday night. Whitmer's office released the letter Friday evening.

Enbridge spokesman Ryan Duffy said as part of seasonal maintenance work, the company discovered a screw anchor support had shifted from its original position.

"This is an issue affecting that anchor support and not the pipeline itself," Duffy said.

"We immediately shut down the Line as a precaution and are inspecting the area with divers and the entire pipeline with remotely operated vehicles," he added.

Enbridge provided this photo documenting damage to the west pipeline of Line 5 caused by an April 2018 anchor strike to a U.S. Senate committee.

On Friday, the governor requested Enbridge turn over "all relevant information about this most recent damage." In her letter to Monaco, she asked Enbridge to "provide affirmative evidence, including appropriate diagnostic testing, that establishes the integrity of the dual pipelines in the Straits of Mackinac."

 "The information I have received about this incident leaves many unanswered questions as to the cause of this damage, the catastrophe that may have been narrowly avoided, and the threats that may remain as a result of the damaged infrastructure," Whitmer said in a separate statement.

According to the statement, Enbridge "alerted" the state that an anchor support on one of the dual pipelines in the Straits of Mackinac had incurred "significant damage."

The support lies about 150 feet from a section of the pipeline where damage to the pipeline coating was discovered on or around May 26, according to the governor's office.

After discovering the new damage, Enbridge shut down the pipeline and is gathering more information through divers, the use of a remotely operated vehicle and other means, according to the governor's office.

The state is asking Enbridge to provide "all engineering reports, photographs, video  and other demonstrative evidence of the damage by Monday.

Duffy said Enbridge will provide all of the information Whitmer has requested. But he had no estimate when the shutdown of Line 5 will be over. That will happen after planned inspections are completed, he said.

The news Friday was the latest development in years-long debate about the 66-year-old Line 5 in the Straits of Mackinac as environmental groups have voiced concern about the potential for a rupture and called for the line to be shuttered.

When it's operating, Line 5 transports up to 540,000 barrels per day of light crude oil, light synthetic crude, and natural gas liquids, according to Enbridge.

In May 2019, Whitmer ordered state officials to issue rules requiring large vessels to verify that no anchors are dragging before passing through the Straits of Mackinac to prevent damage to the Line 5 oil and natural gas pipelines.

The governor's directive to the state Department of Natural Resources followed an April 2018 anchor strike that severed two underwater transmission lines and dented the east and west fuel pipeline spans of Line 5.  Whitmer asked the U.S. Coast Guard to hold foreign vessels to the same standards.

Last week, the Michigan Court of Appeals unanimously upheld the constitutionality of a 2018 law that allows Enbridge to build a tunnel to house the pipelines and protect them from potential damage.

Then-Gov. Rick Snyder Snyder said two years ago the $350 million to $500 million tunnel would eventually eliminate "nearly every risk" of an oil leak into the Straits. His top environmental official argued the tunnel would “provide permanent protection for our Great Lakes” by separating the Line 5 oil pipeline from direct contact with the water.

The three-judge panel rejected the arguments of Attorney General Dana Nessel, who argued that the law signed by Snyder violated the Michigan Constitution's title object clause.

In a Friday statement, Nessel said Line 5 is a "clear and present danger to our Great Lakes and to the millions of Michiganders who rely on those lakes for recreation, business and tourism."

"We anxiously await the immediate production of information from Enbridge in response to Gov. Whitmer’s request so that we can evaluate what, if any, additional action my department may need to take," Nessel said. "In any event, this underscores why we will continue to vigorously pursue our lawsuit seeking to shut down the Straits pipelines."

Staff Writer Karen Bouffard contributed.