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State closer to approving $500M Line 5 utility tunnel at Straits

Date Posted: December 14 2018

LANSING – Construction of a new utility tunnel between Michigan’s peninsulas is closer now that the state Legislature and Gov. Snyder have agreed on the formation of a governing “Mackinac Straits Corridor Authority.” 

Gov. Rick Snyder’s signature on the legislation this month creates the new three-member authority which will oversee the construction of, and ownership of, the tunnel. The tunnel would house a replacement for Enbridge Energy’s controversial Line 5 oil and gas pipeline in the Straits and other utilities.

The concept behind the tunnel would be to eventually abandon the existing pair of Enbridge petroleum pipelines that sit atop the bed of the Straits, 120 feet below of the water’s surface between St. Ignace and Mackinaw City. While the 1950s-era pipelines have never leaked, a hit by a ship’s anchor or some mechanical failure resulting in a petroleum spill would devastate the region. The proposed 21-foot-diameter concrete utility tunnel, which would be sited in bedrock some 100 feet below the Straits, would encapsulate the pipelines and presumably capture any leaks.

“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 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 bill creating the new tunnel authority, sponsored by Sen. Tom Casperson, R-Escanaba, would bind the new panel to initiate an agreement on the construction, maintenance, operation and decommissioning of the existing utility tunnel as long as the governor presents the authority his proposed tunnel agreement with Enbridge before Dec. 31, when Snyder leaves office. 

While environmental groups like “Oil and Water Don’t Mix” have loudly called for the Line 5 shutdown and protested any new tunnel construction under the Mackinac Straits, building trades union leaders have called the tunnel an acceptable compromise with environmentalists, a jobs boon for trades workers in the region, and great news for propane supplies and prices in the Upper Peninsula.   

Michigan Building and Construction Trades Council President Steve Claywell said construction of the new tunnel “will generate hundreds of millions of private investment on our side of the border. That money, which will all come from Enbridge, will generate jobs for residents here and revenue for local and state government. State lawmakers should exercise oversight to make sure their constituents get the maximum benefit, but the idea we won’t get something from Line 5 replacement is silly.”

Canadian-owned Enbridge’s Line 5 is a 645-mile petroleum pipeline that runs from Superior, Wisconsin, across the Upper Peninsula, through the Straits,  down to the Thumb, and over to Sarnia, Ontario. Line 5 is 30 inches in diameter, except when crossing the Straits of Mackinac, where it divides into two 20-inch diameter pipes.  The line became operational in 1953 and carries up to 540,000 barrels or 22.7 million gallons of light crude oil, synthetic crude, and natural gas liquids per day. Line 5 delivers 65 percent of the propane that heats Upper Peninsula homes, and 55 percent of Michigan’s propane needs.

State Republicans are pushing to vote and complete passage of the new pipeline tunnel before the end of the year, as governor-elect Gretchen Whitmer has expressed opposition to the plan