JUDY WOODRUFF: Concern continues to rise across the country about the nation’s aging infrastructure. That concern is particularly apparent when looking at older pipelines that carry crude oil and natural gas.
One of those pipelines carries oil under some of the most pristine water in the country, the Great Lakes’ Straits of Mackinac in Michigan. Scientists say a spill in the straits would be an environmental and economic disaster.
Elizabeth Brackett from public television station WTTW in Chicago reports.
ELIZABETH BRACKETT, Special Correspondent: The air is crisp and the water is cool in the Northern Great Lakes, a body of water that contains 90 percent of the freshwater in the United States. And it’s the reason nearly a million tourists visit Mackinac Island every year.
WOMAN: You’re back for another season? All right.
ELIZABETH BRACKETT: But this year, islanders have more on their minds than tourists. Just north of the famed Mackinac Bridge, two aging pipelines carry 20 million gallons of crude oil and natural gas a day under the Straits of Mackinac.
Longtime island resident and former biological sciences professor Lorna Straus worries about a possible pipeline break.
LORNA STRAUS, Mackinac Island Resident: It would be a devastating thing. Oil is very hard to clean up, so I guess I’m worried that a leak would be an impossible — close to an impossible thing to solve.
ELIZABETH BRACKETT: Pipeline number five is owned by Enbridge Energy. The Canadian company operates the largest crude oil and liquids pipeline system in the world.
Line 5 is 645 miles long. It stretches from Wisconsin across Michigan’s upper and lower Peninsulas and terminates in Ontario, Canada. The 30-inch pipeline splits into two 20-inch lines when it crosses 4.5 miles under the lake.
Lake Michigan and Lake Huron join here at the Straits of Mackinac. Because this area is far from any major urban center and because the shoreline is lined with forest and not agriculture, very little pollution gets into this water. That means these waters are some of the most pristine in all of the Great Lakes.
Thirty million people depend on the Great Lakes for their drinking water. And company spokesman Jason Manshum says that’s one of the reasons why Enbridge works so hard to keep Line 5 safe.
JASON MANSHUM, Enbridge Energy: Line 5 has been in operation here in Michigan for more than 60 years, and it’s been operating safely and reliably at the straits. We have not had any incidents over that four-and-a-half-mile stretch.
ELIZABETH BRACKETT: It’s those 62 years underwater that trouble retired Dow Chemical engineer Gary Street.
GARY STREET, Former Chemical Engineer: My biggest concern is that the line is very, very old. It’s probably suffered the usual wear and tear that any older facility can suffer. I think there’s a real reason to be concerned that the line could fail at almost any time.
JASON MANSHUM: Over the last decade, we have safely transported more than 13 billion gallons of crude oil throughout the U.S. and Canada. That’s a success rate of 99.9993 percent.
ELIZABETH BRACKETT: But a National Wildlife Federation report found that Enbridge was responsible for more than 800 oil spills between 1999 and 2010.
Aging pipelines are a national concern. Over 5,000 spills were reported to the federal government over the last 15 years, including this major spill in Michigan. In July of 2010, an Enbridge pipeline ruptured in the Kalamazoo River, dumping one million gallons of oil near Marshall, Michigan.
Enbridge spent $1 billion and three years on cleanup, and the EPA says oil still remains in the Kalamazoo. Environmental activist Jim Lively says it was that spill that prompted concern about the safety of the Enbridge pipeline in the Straits of Mackinac.
JIM LIVELY, Groundwork Center for Resilient Communities: Just weeks before that spill, they said very much the same thing, no concerns this pipeline is very safe. And then it leaked for 17 hours over a million gallons into the Kalamazoo River. The largest inland oil spill in America happened right here in Michigan.
JASON MANSHUM: What the incident did in the Kalamazoo River, ultimately, is it’s made us a far safer company. We have gone through pretty radical wholesale changes across the board on things like advanced leak detection, pipeline integrity, training of our personnel.
ELIZABETH BRACKETT: The pipeline in the straits is now monitored with computerized systems that operate both inside and outside the pipeline. The findings are analyzed in Enbridge’s control room that operates 24/7 in Edmonton, Canada.
In addition, Manshum says, dive teams physically inspect the pipeline every other year.
JASON MANSHUM: But it hasn’t aged in the bottom of the water. The coating is in fantastic shape and the steel has not deteriorated. It looks just like it did in 1953.
ELIZABETH BRACKETT: Though there is one difference, says engineer Gary Street: The pipeline is now covered with invasive mussels, which didn’t enter the Great Lakes until the 1980s.
GARY STREET: Zebra mussels create three problems. They create extra weight on the pipeline, weight that was never allowed for in the design of the pipeline. They mask any problems from the outside that could be observed by a diver or by a remote camera. And the third thing is that the zebra mussels excrete a very acid material. If that acid material were to get behind the protective coating, it will cause corrosion, and the line will fail prematurely.
ELIZABETH BRACKETT: What nearly everyone up here agrees on, even Enbridge, is that an oil spill in these pristine waters would have a major impact.
Ecologist Knute Nadelhoffer of the University of Michigan’s Biological Field Station says the environmental impact of a spill could take years to overcome.
KNUTE NADELHOFFER, University of Michigan: This is a fairly simple food chain. We have a limited number of algae in the water, limited number of species, aquatic plants on the shorelines, compared to more diverse ocean systems. Chemicals will propagate through this system faster. They are likely to change the system in ways that affect it for decades or centuries.
ELIZABETH BRACKETT: As the mayor of Mackinac Island gets ready to open her hotel for the season it’s not the next decade or century she’s thinking about. It’s the impact of an oil spill right now.
MAYOR MARGARET DOUD, Mackinac Island: Mackinac is the gem of Michigan as far as a tourist destination. It would be just catastrophic if something happened in the straits area.
ELIZABETH BRACKETT: Enbridge insists a pipeline failure in the straits would be detected almost immediately.
JASON MANSHUM: We have isolation valves on each side of the straits to isolate that particular section. And those valves will be completely closed within three minutes.
GARY STREET: You shut the line at Mackinac City, you shut it off at St. Ignace, you still have 325,000 gallons in each of those lines that could spill, that can and will spill into the straits.
ELIZABETH BRACKETT: That’s why activists say the only sure way to avoid a possible environmental and economic disaster is to shut the pipeline down.
JIM LIVELY: I believe that Enbridge is trying hard to make sure that they could minimize a spill. Of course they’re trying hard to do that. But do I trust them? No. Should we trust them? Of course not, not with this, not with the Great Lakes.
ELIZABETH BRACKETT: Shutting down the pipeline is one of the options being considered by a pipeline task force chaired by Michigan’s attorney general. The commission will also look at the economic impact of shutting down the four-and-a-half-mile stretch under the Straits of Mackinac.
For the PBS NewsHour, I’m Elizabeth Brackett in Chicago.