Risk, Consequences, and Probability
Guest Opinion
At the Northern Michigan Policy Conference, Democrat Hill Harper replied to the Republicans voicing their support for Line 5, saying, “We’re playing literally with poisoning our Great Lakes, which would be catastrophic to Michigan’s economy, catastrophic to Michigan’s tourism. And the juice is not worth the squeeze in this case.”
My thoughts exactly. The consequences of a Great Lakes Line 5 failure are easy to envision and often cited. But every risk assessment has two parts: risk = consequences x probability. The probability half of the equation is often overlooked. The probability of failure increases with age, but like the frog in a pot of slowly heating water, it’s gradual and unnoticed.
I decided to ask ChatGPT, an artificial intelligence content generator, for help. It instantly replied, “Estimating the probability of failure for oil pipelines involves a comprehensive risk assessment. Factors considered include the pipeline’s age, material, maintenance history, geographical location, environmental conditions, and the potential for corrosion or mechanical damage.” Let’s examine these generic factors for Line 5.
Age of Line 5: 70 years, designed for 50. In 2018, Governor Snyder said Line 5 could operate until a tunnel for a new Line 5 was completed, so Line 5 will be almost 80, still operating, when a tunnel is bored below it. Promising a tunnel keeps Line 5 earning $1.76 million per day ($6 billion total) in the decade a new tunnel will take. When the Army Corps of Engineers finishes its tunnel review in 2025, Enbridge gets to choose whether or not to build it.
Material: 1953 era material is outdated. Corrosion protection was a wrap coated with coal tar, much of which is now compromised.
Maintenance history: Enbridge calls design changes “routine maintenance” to avoid accountability. When Line 5 bottomland support eroded, 200 brackets were needed to support it. This “fix” suspends the pipeline, causing bending and vibration stresses, and makes Line 5 more vulnerable to anchor strikes. The new design required an engineering review it never got.
Geographical location: The Mackinac Straits were called “the worst place in the U.S. for an oil pipeline” by Pipeline Hazardous Materials & Safety Administrator Elliott at the 2018 Anchor Strike Hearing.
Environmental conditions: Erratic currents in the Straits are so strong, oil could spread into Lake Michigan and almost to the thumb in Lake Huron according to the University of Michigan. Line 5 now sways like a suspension bridge. It is also covered with invasive mussels, which impede inspection. And yet Enbridge chooses the Straits route instead of its pipelines on land to the same destination.
Potential for corrosion: Gaps in the corrosion coating occur when the pipeline scrapes against the support brackets, exposing metal. Enbridge calls these bare spots “holidays” yet does not always report them.
Mechanical damage: In 2018 an anchor dented Line 5. Support structure E-17 was damaged in 2020, causing a temporary shutdown, which Enbridge attributed to a strike by its own vessel.
These factors combine to make the probability of failure for Line 5 unacceptably high. Yet like the elephant in the room, Line 5 goes unmentioned in Great Lakes symposiums and commissions. The Great Lakes Restoration Initiative (GLRI) spends billions, but without addressing Line 5, GLRI is funding restoration at risk of ruin.
Protecting the Great Lakes against invasives and pollution is important, but these studies take years. Fix the underlying problem first. Simply turning one valve could quickly resolve the lakes’ greatest threat: oil.
Line 5 is one section of a 2,000-mile pipeline between Alberta and Montreal. It crosses the Upper Peninsula along Lake Michigan, an especially dangerous section, but the whole 645-mile pipeline is decrepit and in need of replacement, not just the four underwater miles. It has already leaked 33 times.
Enbridge contends that Line 5 is safe and can operate indefinitely, but having no plan to decommission it becomes a de facto plan to operate Line 5 until it fails. The probability of failure is 100 percent if you wait long enough.
When Governor Whitmer ordered Line 5 shut down in 2020, Enbridge sued in defiance. While lawsuits drag on, Line 5 continues to deteriorate. Michigan bears the risk while Enbridge profits—about 95 percent of the oil goes to Canada. President Biden should shut down Line 5 to protect the interests of Tribes and all citizens, not of Big Oil.
Back to the risk equation: consequence is multiplied by the likelihood of its occurrence. Consequences of Line 5 failure would clearly be catastrophic for Michigan’s economy, 700 miles of shoreline, and 20 percent of Earth’s fresh surface water. But the probability of failure is insidious, and 70 years of deterioration is out of sight.
Line 5 must be shut down to protect the Great Lakes before its gradual decline becomes sudden and Earth’s largest freshwater system is devastated. “The juice is not worth the squeeze in this case” for Michigan, or for the world.
Barbara Stamiris is an environmental activist living in Traverse City.
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