Line 5 of the Enbridge oil pipeline system consists of two steel pipes 20 inches in diameter that lie at the bottom of the Straits of Mackinac, a narrow strip of water separating Michigan's upper and lower peninsulas. The Canadian energy company Enbridge brought Line 5 online in 1953; today, the pipes help transport nearly 23 million gallons of crude oil a day between the US and Canada.
The five-mile stretch of pipeline under the straits is situated at the meeting point of Lake Huron and Lake Michigan — two of the five Great Lakes that together hold 90 percent of America's fresh water. The strait lies just west of Mackinac Island, a popular tourist destination listed as a US Historic Landmark. And the channel generates extremely powerful currents — they can flow east or west — that at times create a flow of water more than 10 times greater in volume than Niagara Falls.
"If you were to pick the worst possible place for an oil spill in the Great Lakes, this would be it," Dr. David Schwab, a research scientist at the University of Michigan Water Center, told VICE News. "The currents are powerful and change directions frequently. In the event of an oil spill, these factors would lead to a big mess that would be very difficult to contain."
A spill on the Great Lakes could impact the drinking water they provide for 40 million people in the US and Canada, the $7 billion fishing industry, and the $16 billion recreational boating economy.
An animation showing how a 1 million gallon oil spill beneath the Straits of Mackinac would spread throughout the region.
In July 2013, the NWF commissioned a dive to examine Line 5. The footage shows one of the pipes suspended over the bottom of the straits at points, with supports having broken away.
"My first reaction was that I didn't see anything there that would cause me to panic," Richard Kuprewicz, president of pipeline safety firm Accufacts and a member of the watchdog organization Pipeline Safety Trust, said after reviewing the footage "We didn't see any areas where there's large amounts of span between the supports, though we did see some areas where clearly the pipe is not sitting on the bottom of the lake."
A year after the NWF dive, Michigan Attorney General Bill Schuette told Enbridge to install new supports on Line 5; Enbridge recently completed the installation. Kuprewicz told VICE News that if maintained properly, submerged oil pipelines can operate safely — and that Line 5 is in a relatively hospitable environment.
"Fresh water is a lot better than sea water, and there are lines in seawater that last many decades," he said. "[The pipelines in Line 5] are very thick, and there doesn't seem to be any corrosion. They're fairly deep and the depth makes them fairly cold. There's always corrosion potential in steel pipelines, but cold water temperature makes this fairly low."
The National Wildlife Federation dives to Line 5.
Still, when the NWF video was posted, public reaction surprised even Beth Wallace, then the NSF community outreach regional coordinator in Ann Arbor.
"When we released the video, it immediately shot up to 30,000 views, which is a lot for this issue," she said. "More importantly, it caught the attention of a lot of local officials in the area."
In December of 2013, US senators Debbie Stabenow and Carl Levin of Michigan and Senator Dick Durbin of Illinois wrote a letter to the US Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA) — the federal regulatory body for pipelines. The senators highlighted the sensitive placement of the pipeline and the economic impact a rupture could have, pointing out that the Great Lakes "are directly connected to over 1.5 million jobs, with $62 billion in annual wages."
The location of Line 5 isn't the only thing elevating concern over a potential spill. Enbridge does not have a sterling environmental record. In July 2010, the company's Line 6B ruptured and released more than 1 million gallons of tar sands oil into the Kalamazoo River System near Marshall, Michigan. (According to Wallace, Line 5 under the Straits of Mackinac is about a decade older than Line 6B.) The clean-up cost nearly $1 billion. It was the the worst onshore oil spill in US history.
In addition, the company had more than 800 spills in North America between 1999 and 2010. All told, those spills released about 7 million gallons of oil.
Wallace said neither PHMSA nor Enbridge has been forthcoming with information, a lack of transparency that motivated her and the NWF to dive down to Line 5 after the group released a 2012 report on the pipeline. Kuprewicz also said Enbridge could alleviate public anxiety over Line 5 if the company did a better job of communicating openly with the public.
PHMSA adopted additional pipeline safeguards following the 9/11 terrorist attacks. These included, "Reducing public access to sensitive information on our nation's pipeline infrastructure, including restricting access to certain information contained in the National Pipeline Mapping System."
Wallace and other activists allege that PHMSA cites these safeguards too often to deny information requests.
"Their excuse was they didn't have the information we were asking for and it was a national security risk," Wallace said. "They didn't want to disclose certain information because we might be terrorists and we might go blow things up."
Enbridge did not respond to repeated requests for comment from VICE News.
Despite the concern from environmentalists, politicians, and locals, the company has moved to expand Line 5's capacity by 1.8 million gallons of oil per day. But the stakes are too high, Wallace said, to increase oil production in such a sensitive area when questions about safety and disaster response are unanswered.
"A spill would completely devastate the region," she said, "if not the [entire] upper Great Lakes."
Follow Nilo Tabrizy on Twitter: @ntabrizy
Photo via Flickr