Enbridge, MI Plan for Line 5 Changes


Canadian energy firm Enbridge entered into an agreement last week with the state of Michigan, promising to evaluate options for replacing its Line 5 liquids pipeline under the Straits of Mackinac and to take action to replace the same line under the St. Clair River.

According to the new agreement, Enbridge will, by next June, evaluate three alternatives for the “eventual” replacement of Line 5 under the Straits: building a new pipeline in a tunnel, installing a new pipeline via horizontal directional drilling, or installing a new pipeline in a trench under the Straits, within some sort of secondary containment structure.

The agreement does not actually require Line 5’s replacement or put a timeline on the job, but reflects the pressure the state is putting on Enbridge to plan for that outcome.

More immediately, Enbridge says in the agreement that it will shut the pipeline down under the Straits when weather creates sustained waves of over 8 feet on the body of water. A report issued earlier this year by the National Wildlife Federation, authored by former Dow Chemical engineer and fluid dynamics expert Edward Timm, held that “certain sections of the twinned sections of Line 5 under the Straits may be only one peak current event away from catastrophic failure.”

Other Provisions

Enbridge will also begin work on replacing the stretch of Line 5 under the St. Clair River using horizontal directional drilling immediately upon receiving government permits. As part of the agreement, the company says it will increase transparency and coordination with the state regarding the safety of the pipeline.

Line 5 map

Line 5, which itself runs from Wisconsin to Sarnia, Ontario, conveys crude oil and natural gas liquids originating in Alberta to Ontario.

“Business as usual by Enbridge is not acceptable and we are going to ensure the highest level of environmental safety standards are implemented to protect one of Michigan’s most valuable natural resources,” Gov. Rick Snyder said in a press release. “The items required in this agreement are good strides forward. The state is evaluating the entire span of Enbridge’s Line 5 pipeline and its future, but we cannot wait for the analyses to be completed before taking action to defend our waterways.”

Pipeline Controversy

Enbridge has been under increasing fire over the past year from citizens, activists and lawmakers in Michigan who are concerned about the condition of the 64-year-old dual pipeline under the Straits. Last month, Gov. Rick Snyder publicly called on Enbridge to be more transparent about the line after a series of revelations of coating damage on the pipes under the Straits.

In February, Enbridge denied reports of coating loss on the pipeline. In March, the company acknowledged that there were areas of coating loss, but that they only affected the outer layer of the coating system.

More recently, it was revealed that there were areas of bare metal on the line under the Straits, and some Enbridge personnel knew about the gaps soon after they were created in 2014, but the company hadn’t acknowledged their existence for three years. In November, Enbridge revealed that, rather than the three gaps in the coating that the company originally reported, there were dozens of areas of bare metal, some larger than one square foot in area.

Safety Record

Line 5, which originates in Superior, Wisconsin, where several other Enbridge lines terminate, moves crude oil and natural gas liquids to Sarnia, Ontario, via Michigan. According to Enbridge, while much of the crude coming from Alberta goes to refineries in Sarnia, some is also refined in Michigan and Ohio. And it’s not all Canadian oil moving through the pipeline: At points, sweet crude produced in Michigan is pumped into Line 5 to make its way to refineries as well.

Enbridge has held that the pipeline’s integrity has never been compromised. The line has never had a leak in over six decades of service, and this past summer, it passed a pressure test ordered as part of the company’s consent agreement, established after the 2010 spill on its Line 6B.

Enbridge has repeatedly asserted that many of citizens’ and government officials’ concerns about the state of the pipeline have stemmed from misinterpretations of internal documents and procedures.

“We realize our internal technical studies and understanding haven’t translated well into reassuring the public or Michigan leaders about the ongoing safe operation of Line 5,” the company said in a press release on the agreement. “We apologize if our actions sometimes have created confusion.”


Tagged categories: Government; Infrastructure; NA; North America; Pipelines; Quality Control

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