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Agreement paves way for Enbridge to permanently shut down, replace Line 5 in Straits of Mackinac

Accord between the state and company requires Enbridge to pay all costs for a multi-use tunnel beneath the Straits, compels safety improvements on other water crossings

Wednesday, Oct. 3, 2018

LANSING, Mich. – The state of Michigan and Enbridge Energy today announced an agreement that will lead to major safety enhancements along the entire length of the Line 5 petroleum pipeline crossing the state, permanently shut down the current segment that crosses the Straits of Mackinac, and construct a multi-use utility tunnel beneath the Straits. All costs for the tunnel will be paid by Enbridge.

Under the agreement signed today, Enbridge would pay for all design, construction, operation and maintenance of the tunnel for up to 99 years, subject to approvals by the Mackinac Bridge Authority. Tunnel construction is estimated to cost between $350 million to $500 million over the 7- to 10-year duration of the project. This major infrastructure initiative for northern Michigan, which would be owned by the Mackinac Bridge Authority and in which Enbridge would lease space, also could house additional infrastructure, such as broadband and electrical lines.  

“This common-sense solution offers the greatest possible safeguards to Michigan’s waters while maintaining critical connections to ensure Michigan residents have the energy resources they need,” said Gov. Rick Snyder. “The historic agreement will result in eliminating nearly every risk of an oil leak in the Straits and provide added protections to the Great Lakes. It also will allow for multiple utilities to be housed and protected, better connecting our peninsulas, improving energy security and supporting economic development. The taxpayers of Michigan will benefit greatly from this project but won’t have to pay for it.” 

The new accord, which builds on a November 2017 agreement between the state and Enbridge, also demands specific actions at sensitive Line 5 water crossings other than the Straits, expanding protections along the length of the pipeline in Michigan.

“Pipeline safety has always been a top priority for me,” said U.S. Rep. Fred Upton, chair of the House Subcommittee on Energy. “I led the bipartisan effort on two major pipeline safety and accountability bills in the last several years. Getting Enbridge to pay for 100 percent of the Line 5 replacement tunnel is the right approach and one I’ve sought since day one. I want to thank the State of Michigan, and Governor Snyder, for their clear-headed leadership on this issue. This agreement needs to get done as quickly as possible for the protection of our Great Lakes.”

“Since taking office 20 months ago, I’ve worked closely with Gov. Snyder to ensure our Straits remain safe while maintaining the flow of pipeline commerce,” said U.S. Rep. Jack Bergman. “The proposed tunnel is a forward-thinking, innovative approach ensuring safety and continued economic stability. Michigan’s First District is long overdue to benefit financially from the continuous flow of products transiting our area. I will work tirelessly to ensure that the economic advantages from our energy infrastructure directly benefit the constituents of the First District.”

Assessments to date of the Line 5 Straits crossing confirm the pipeline’s integrity. However, the agreement will demand additional measures to reduce risk during tunnel construction. Those safety measures will:

  • Assure the Straits pipeline is not operating when high waves would severely hamper response to a potential oil spill. The agreement requires that Enbridge staff be present at the Straits to be able to shut down the line within 15 minutes – even if power is lost – when wave heights hit 6.5 feet for at least an hour. Enbridge must continue to shut down the Straits pipeline when wave heights hit 8 feet for at least an hour.
  • Provide a new radar system to supply improved, real-time wave-height data at the Straits. 
  • Assure at least $1.8 billion in available funds be provided by Enbridge to respond to a potential oil spill in the Straits or anywhere on Line 5 in Michigan, providing added protections as tunnel construction is completed.
  • Provide consistent state supervision of Line 5 through regular meetings between Enbridge and the state.
  • Install cameras in the Straits, paid for by Enbridge, to support new regulations from the U.S. Coast Guard prohibiting ships in the area from dropping their anchors. This has been identified as one of the most serious threats to Line 5 and other utility lines on the bottom of the Straits. The cameras will allow the Coast Guard to monitor vessels entering the waterways and immediately communicate with those that are operating dangerously.

The new agreement would also:

  • Require immediate additional safety measures at 13 priority Line 5 water crossings, in addition to requiring actions at 68 other crossings as identified in a previous report.
  • Prohibit heavy crude oil from ever traveling through Line 5. 

A previous report conducted by Enbridge and overseen by the state identified a tunnel beneath the Straits as a feasible replacement alternative to the existing Line 5 Straits crossing.

In compliance with the 2017 agreement, Enbridge has already applied for authorizations and approvals to replace the Line 5 crossing at the St. Clair River, a key water body that provides drinking water to a large population in southeast Michigan. That work will begin upon the receipt of those authorizations and approvals. 

Line 5 is 645 miles long and transports up to 540,000 barrels a day of light crude oil and natural gas liquids, including propane. Below the Straits of Mackinac, the pipeline splits into two lines that lie on the lake bottom within an easement issued by the state of Michigan. A new pipeline in the tunnel would not increase volumes or alter the types of products transported through the existing Line 5.