Enbridge’s Line 5 Straits Crossing is safe and fit for purpose, says PHMSA
Pipeline regulator's independent assessment based on 18 years of inspection data
America’s pipeline regulator has given Enbridge’s Line 5 Straits of Mackinac crossing a clean bill of health.
The U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) recently completed an independent review of Enbridge’s inspection data on Line 5, whose twin 20-inch-diameter pipelines travel across the bottom of the Straits of Mackinac, in northern Michigan, for about 4.5 miles.
PHMSA’s review, which can be found on its website, concluded that the Line 5 Straits crossing is safe and fit for purpose.
The 26-page report is significant because “it is the first independent assessment of Line 5 under the Straits of Mackinac. It provides validation from a third-party expert that these pipelines are in good condition,” says Millan Sen, an engineer with Enbridge’s Pipeline Integrity department.
“That’s important reassurance,” he adds, “for everyone who cares about the waters of the Great Lakes.”
The Line 5 Straits crossing has never experienced a leak in more than 60 years of operation. It’s the most inspected segment of pipe in Enbridge’s crude oil network, and those examinations include:
- Autonomous Underwater Vehicle (AUV) inspections, using side-scan sonar, conducted every two years;
- Visual inspections, involving Remote Operating Vehicles (ROVs) and/or expert divers, also conducted every two years; and
- Internal inspections with high-tech tools (much like mini-MRI machines), which detect features and movement in the nearly-one-inch-thick carbon- steel walls of the Line 5 Straits crossing pipeline, that have been carried out three times in the past five years.
PHMSA engaged Lamontagne Pipeline Assessment Corporation to conduct its independent review, which involved examination of inspection reports of the Line 5 Straits crossing dating back to 1998.
The Michigan Oil and Gas Association (MOGA), which represents hundreds of Michigan-based and family-owned crude oil and natural gas producers, made note of PHMSA’s Line 5 report on its website.
“We rely on Line 5 to be the safest and most efficient means of transporting light crude oil produced throughout northern Michigan to refineries in southeast Michigan, northern Ohio and throughout the region,” the association said in a statement. “Hence, we have a keen interest in the continual maintenance and condition of Line 5.”