Dangerous Straits
Two 63-year-old pipes lie exposed at the bottom of the current-whipped Straits of Mackinac, determined by one expert to be ‘the worst possible place’ for a spill in all the Great Lakes
Fourth of five parts It seemed like a no-brainer at the time. Instead of using tankers to haul crude oil across the treacherous open waters of the Great Lakes, in 1953 a Canadian pipeline company determined it would be easier and cheaper to take that oil off the lakes, put it in a pipe, and pump it hundreds of miles overland to Midwestern refineries.
The pipeline builders had two choices to get the oil to market from a terminal in far northern Wisconsin on the western shore of Lake Superior.
They could tunnel down the length of Wisconsin, around the southern shore of Lake Michigan and across Michigan’s Lower Peninsula to the refinery city of Sarnia, Ontario. Or they could take a more northerly route, digging through Michigan’s Upper Peninsula and then southward across the Lower Peninsula.
The northern route was shorter, but there was one mighty obstacle, the Straits of Mackinac — a roughly 4- to 5-mile-wide channel between Lakes Michigan and Huron that is whipsawed by currents unlike anywhere else in the Great Lakes.
Engineers figured they could solve the problem by splitting the pipeline into two narrower pipes where it reached the water’s edge, then doubling the thickness of the steel on the smaller pipes and coating them with an enamel skin.
It was all protection enough, the builders figured, to allow the
twin tubes to be laid across the lake bottom. Nothing like it had ever been tried: “It is the longest and deepest job we’ve done since we started this sort of work in Arabia some 15 years ago,” the project’s lead engineer said at the time.
The plan was to initially run about 120,000 barrels of oil through the Straits per day and gradually ramp that up to 300,000 barrels per day. Over time the volume grew.
The pipes were not expanded, replaced or thickened to increase the oil and natural gas they carry; the capacity was largely added by increasing pressure on the steel tubes. In 2013, the pipeline owner ratcheted up the maximum capacity on the lines to 540,000 barrels per day.
That is a volume far greater than the 470,000 barrels per day planned for the state-of-the-art Dakota Access Pipeline, which drew thousands of protesters to the Great Plains this fall. Many were upset over the risk the Dakota line poses to the Missouri River, though engineers never planned to drape the pipe across the river bottom. Instead, they prepared to tunnel the pipe as deep as 115 feet below the riverbed to protect the waters above.
Given the age of the Mackinac lines, and the fact that they were laid in what one prominent hydrodynamics expert now calls the “worst possible” place for an oil spill in the Great Lakes, environmentalists, politicians and Michigan regulators are taking a new look at the old pipes.
Many still see the idea of running oil lines through the heart of the Great Lakes, home to 20% of the world’s fresh surface water, as a no-brainer. But from the opposite perspective.
“Certainly, the Straits pipelines would not be built today,” Michigan’s Republican Attorney General Bill Schuette has said. “So how many more tomorrows (they) should operate is limited in duration.”
The State of Michigan has ordered a study of the environmental and economic risks the pipes pose to the Great Lakes, as well as an analysis of other ways to deliver the 23 million gallons of crude and natural gas they are capable of carrying each day.
One obvious alternative would be to move that oil along a pipeline route that runs the length of Wisconsin and wraps around the southern shore of Lake Michigan. It is operated by the same oil pipeline giant, Enbridge Energy Company Inc.
Both studies, funded by Enbridge but not overseen by the company, are expected to be completed later this year.
In the meantime, resolutions calling for closing the Michigan pipes or vastly restricting them have been passed by more than 60 Michigan local governments, including Detroit, Lansing, Ann Arbor, Traverse City and Kalamazoo.
Enbridge complains it has become the victim of fearmongering. Company executives say the Mackinac lines were built for the ages and that regular inspections using side-scan sonar, remote cameras and MRI-like devices placed inside the carbon steel tubes prove they are basically as good as new. They argue there is no reason to talk about scrapping or rebuilding them — now or in the foreseeable future.
“We know from the many levels of inspections and diagnostics that the line is in very good condition and can continue to safely operate indefinitely so obsolescence is not a factor,” company officials wrote in a 2015 memo to Schuette, the attorney general, and to former Michigan Department of Environmental Quality Director Dan Wyant.
Wyant and Schuette’s response, which came in a report prepared by the Michigan Petroleum Pipeline Task Force: “This is not a reasonable position.”
As Enbridge assured the public its pipelines were highly unlikely to leak, the company also announced in June it would invest $7 million in oil spill cleanup equipment designed for the Arctic-like environment of the Mackinac Straits.
“Hopefully, we’ll never need it, but it’s there,” said Enbridge spokesman Ryan Duffy.
Enbridge also has stationed a half dozen employees in a garage-like building tucked behind the Family Fare grocery store in St. Ignace, on the northern shore of the Straits. The crew’s job, beyond basic daily maintenance work, is to be ready around the clock — and around the calendar — if the pipelines crack.
Enbridge officials insist the Mackinac pipes are different from any other section in their vast network of North American pipelines because the Mackinac pipes were specifically engineered to withstand the Straits’ brutal underwater environment.
Even some of the company’s staunchest critics concede the twin lines, old as they may be, remain an engineering marvel.
But that doesn’t mean the risk the pipes pose to the world’s largest freshwater system is small.
“Risk is an equation, P times C — probability times consequence,” says Traverse City attorney Jim Olson, founder of the environmental group FLOW, which is calling for the pipes to be shut down.
“If the magnitude of the consequence is high, the probability doesn’t really matter. That is the case here. This is like the ammunition plant in the middle of a city. You just wouldn’t build an ammo plant in the middle of a city.”
Better than boats
In 1950, Enbridge’s predecessor, Interprovincial Pipe Line Company, built a pipeline linking the newly developed Alberta oil fields to the western shore of Lake Superior. The first barrel of oil took 26 days to make the 1,150-mile trip from Edmonton to Superior.
The oil that flowed across the continent that winter was stored in tanks near the lakeshore until the spring thaw. It was then loaded onto a specially built fleet of 620-foot-long tankers, each of which cost $4.5 million and could hold 6 million gallons of crude, then shipped across Lakes Superior and Huron to the refinery city of Sarnia.
Beyond the cost and time of loading and unloading the oil, and the risks involved with floating it across some of the stormiest freshwaters on the globe, the tankers could only operate for eight ice-free months each year. Nevertheless, that first season boats hauled nearly 600 million gallons across the lakes without incident — almost.
Near the end of the season one of the new ships exploded while docked in Sarnia, just after its hold had been emptied of 5 million gallons.
One person was killed and five were injured. It could have been far worse had the tanker not been empty; the explosion happened just 300 yards from a cluster of refinery tanks, and those tanks were only about 800 yards from Sarnia’s main business district.
In 1952, pipeline builders began to explore a safer option — laying a steel tube from Superior to Sarnia. After briefly considering routing the pipe through Wisconsin, the company opted to take the shortcut across the Upper Peninsula. The project required laying 645 miles of pipe, including crossing the Straits of Mackinac, which is nearly 250 feet deep in places.
The engineers wanted to split the line where it crossed the Straits into two smaller pipelines because those would be easier to install, and if one of the twins needed to be turned off, oil could keep flowing through the other.
The configuration also allowed the pipes to operate well below the maximum pressure they were designed for, which was safer and increased their lifespan.
The pipeline builders traveled throughout the region in early 1953 selling the concept to residents as “essential to the defense of the United States and the whole North American continent.”
It cost the company just $2,450 to get an easement across the state-owned lake bottom to lay two pipes that were made of steel nearly 7/8-inch thick, about double the gauge of the pipe that would run over land.
The agreement said the pipes must be buried in the lakebed until the water reached a depth of 65 feet, to protect them from ice and anchor damage from freighters traveling the congested shipping corridor. Michigan also required that the pipes not stretch unsupported for more than 75 feet along the rolling lake bottom, to keep the pipes from swaying — and possibly cracking — in the swift, ever-changing currents.
The pipeline builder knew the stakes were high because of the pipes’ potential to break in the Straits, which the company noted would be financially disastrous.
“Not only would the construction of such a line be a very costly venture, which would have to be completed during the relatively brief period during late spring and summer when the Straits were not frozen over but the loss in revenue which would result from any possible break in the line and shutdown of the flow would be of the most serious importance,” a company report at the time stated.
The company added that the possible contamination of lake waters also was a concern, and that it would make “every effort” to ensure that this would not happen.
“Operation Big Pull” began the first week of August 1953.
It required hundreds of laborers and engineers to weld sections of pipes into tubes approximately 4 miles long. They were assembled by welding 27foot sections, though each individual section has no seam running its length — a distinct safety feature of the lines. The pipes were then dragged into the lake with a cable attached to a specially built winch.
The $8.5 million project was hailed in the press as “the engi-
“We know from the many levels of inspections and diagnostics that the line is in very good condition and can continue to safely operate indefinitely so obsolescence is not a factor.” ENBRIDGE OFFICIALS, IN A 2015 MEMO TO BILL SCHUETTE, MICHIGAN ATTORNEY GENERAL, AND DAN WYANT, FORMER MICHIGAN DEPARTMENT OF ENVIRONMENTAL QUALITY DIRECTOR “This is not a reasonable position.” SCHUETTE AND WYANT, IN RESPONSE