Enbridge retains Montana, Florida contractors for Line 5 tunnel construction

Contractors out of Montana and Florida have signed on to construct a four-mile tunnel beneath the Straits of Mackinac to house a new segment of Enbridge Energy's Line 5.

The Canadian pipeline giant announced Tuesday it retained a joint partnership between Barnard Construction Company Inc. and Civil and Building North America Inc. to construct the tunnel.

The groups are "industry-leading tunneling companies" that have built more than 100 tunnels in 15 countries, including the Port of Miami Tunnel, the Central Subway Tunnel in San Francisco and rail tunnels in Hong Kong, according to Enbridge.

“This agreement with Barnard and CBNA marks a milestone for this historic project," said Tom Schwatz, senior vice president for liquids pipelines for Enbridge Strategic Projects and Partnerships. "The selection of these two world-class companies reinforces our commitment to safely building the Great Lakes Tunnel."

Enbridge put out a request for proposals for tunnel construction contractors in early 2022, but must wait for final approvals from the U.S. Army Corps of Engineers. The corps has indicated it will decide on Enbridge's environmental permits in 2026.

Bozeman, Montana-based Barnard Construction and Miami-based Civil and Building North America Inc. formed a partnership for Enbridge's project called Mackinac Straits Partners, with each company retaining a 50% share.

A subsidiary of Barnard Construction, BFBC, has done work on the border wall at the U.S.-Mexico border, a connection environmental advocates criticized Tuesday.

"As we all know, there is no border wall, and there's not likely to be a Line 5 oil tunnel either," said Sean McBrearty, Michigan director for Clean Water Action.

Enbridge said it will not release the cost of the contract with Mackinac Straits Partners.

The tunnel, initially pegged to cost about $500 million, is likely to increase in cost as inflation and delays continue. Enbridge does not have a new anticipated cost for the project.

The project emerged after years of back and forth between the state of Michigan and Enbridge regarding the safety of the pipeline resting on the lakebed through the Straits of Mackinac between the Upper and Lower peninsulas.

Environmental advocates had pointed to the 2010 failure of an Enbridge line in Marshall as an indication of the catastrophic damage that could occur if the pipeline at the nexus of lakes Michigan and Huron were to rupture. The incident, considered one of the largest inland oil spills in U.S. history, released more than 800,000 gallons of heavy crude oil into a nearby creek and, eventually, fouled 40 miles of the Kalamazoo River.

In 2018, Republican former Gov. Rick Snyder entered an agreement with Enbridge in the final months of his term that required the company to build a $500 million utility tunnel beneath the straits that would contain a Line 5 replacement segment and other utilities.

The design and construction of the line has been beset by setbacks, including longer-than-anticipated permitting delays and challenges in court levied by Attorney General Dana Nessel and Gov. Gretchen Whitmer, both Democrats.

Whitmer dismissed her suit in November 2021, but threw her support behind litigation brought by Nessel also seeking to close the pipeline.

That case is awaiting a decision in the U.S. Sixth Circuit Court of Appeals.

eleblanc@detroitnews.com