Line 5 Pipelines and Extreme Energy

Working to Prevent a Catastrophic Oil Spill in the Straits of Mackinac

The Great Lakes are the pride of the Midwest and belong to the public. Most residents and visitors, however, are unaware that every day nearly 23 million gallons of oil and petroleum products flow through two rusty old pipelines piercing the heart of the Great Lakes, just west of the Mackinac Bridge. Built in 1953, the two 20-inch-in-diameter “Line 5” pipelines owned by Canadian company Enbridge, Inc., lie exposed in the water along the public bottomlands of the Mackinac Straits. 

FLOW’s team of lawyers and scientists has helped spark and define a growing public call to stop the flow of oil in Line 5 through the Straits by:

  1. Identifying the State of Michigan as the key steward to protect our public waters and uses from a catastrophic oil spill under public trust law. 
  2. Concluding that the Line 5 oil pipelines suffer from rust, dents, missing supports, and encrustation by corrosion-causing invasive mussels, presenting an imminent hazard to the Great Lakes that the State of Michigan has a public trust duty to eliminate. 
  3. Studying alternative oil routing options available that do not use the Great Lakes as a high-stakes shortcut to pump crude oil from fields in western Canada to refineries in eastern Canada.

With so much at stake, we ask: why risk the Great Lakes?


The Great Lakes and Waterways Belong to the People, Not Corporations


23 million gallons of oil and petroleum products flow through two rusty old pipelines piercing the heart of the Great Lakes, just west of the Mackinac Bridge.

Enbridge’s Line 5 pipelines in the Straits of Mackinac pose an unacceptable risk to our Great Lakes, which provide drinking water, income, inspiration, and a sense of pride to tens of millions of people and their communities. FLOW and our partners are working together to ensure that the State of Michigan is held accountable as public trustee of our waters to take immediate action to prevent a catastrophic oil spill in the Great Lakes. Time is of essence.

Help Us Protect the Great Lakes

Without the State of Michigan’s 1953 easement, Enbridge could not have built these “Line 5” oil pipelines in public waters and on public bottomlands about two miles west of the Mackinac Bridge. In the six decades since, the state has largely forgotten about its perpetual duty to evaluate the likely impacts to the ecosystem, waters, and public uses from a potential oil spill in the powerful currents at the Mackinac Straits. A leading freshwater research scientist at the University of Michigan called it “the worst possible place for an oil spill” in the world’s largest freshwater basin.

This current controversy involving these underwater oil pipelines and their owner Enbridge—infamous for causing the nation’s largest ever inland oil spill into Michigan’s Kalamazoo River in 2010—exemplifies how citizens can petition their state and provincial governments to exercise their public trust duties and ensure the protection of our common public waters for current and future generations. It’s our water, our bottomlands, and our public trust rights to uphold.

"We must do more than simply hope that Enbridge can avoid, at the Straits of Mackinac, what it allowed to happen in 2010, when an Enbridge pipeline burst near Marshall and poured a million gallons of heavy oil into the Kalamazoo River watershed."

- Governor Milliken

Milliken: Seek alternatives to Straits pipeline quickly

How to Get Involved

FLOW is a leader of the Oil & Water Don’t Mix campaign that is dedicated to working with citizens, communities, and businesses to convince the State of Michigan to uphold its public trust responsibilities to protect the Great Lakes and bottomlands by immediately shutting down the oil flowing through Line 5 at the Mackinac Straits while the state studies alternatives.  Click here to learn more.

In response to the campaign, Governor Snyder formed a task force in 2014 to gather facts about the pipelines, followed by an advisory board in 2015 that is actively studying the risks posed by Line 5 in the Mackinac Straits and alternatives that would not risk an environmental and economic disaster in the Great Lakes.

FLOW’s expert research shows that decommissioning the Straits Pipelines would not disrupt Michigan's or the Midwest's crude oil and propane supply, contrary to assertions by Enbridge. Available capacity and flexibility to meet energy demand in the Great Lakes region already exists in the North American pipeline system.

Visit the Resource Library for our expert reports, press releases, and more on Line 5.

Help Us Protect the Great Lakes
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    2 comments on “Line 5 Pipelines and Extreme Energy

    1. Roger Suppes on

      Just heard an ad on the radio, claiming Michigan residents using propane for home heating, would be affected dramatically by shutting down pipeline 5. Is there any truth to that claim, especially with all the fake news out there. Is propane provided to some UP residents and if so, are there alternative sources available for those residents ?
      Thank you

    2. Arthur Hirsch on

      The Climate Reality Project (West Michigan Chapter) is involved with public education and education about the Line 5 Shutdown and the future Environmental Impact Statement. We are reaching out to the local public and legislators for them to understand the potential risks imposed by a 70 year old pipeline and an foreign pipeline operator. We are striving to bring the LIne 5 issue to Former President Al Gore’s attention (Al Gore started the Climate Change Reality Project. We look forward to working with FLOW and other organizations to protect the vital water resources in our state.


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