Mackinac ferry owner: Why didn't rough September weather shut Line 5?

Beth LeBlanc | The Detroit News

Delta Township — A Mackinac Island ferry operator questioned Monday why Enbridge Energy failed to shut down its pipeline beneath the Straits of Mackinac in September during rough weather that he believed should have prompted a closure.

“If we didn’t shut down that pipe on (Sept.) 21st, then how can we be assured, how can we trust, how can we go into this together?” said Chris Shepler, president of Shepler's Mackinac Island Ferry and a member of the Michigan Pipeline Safety Advisory Board.

Waves on Sept. 21 were consistently above the 8-foot threshold that would require the line's shutdown, Shepler said. Buoy recordings from the day, however, show wave heights that fell just short of eight feet.

The comments came during the first public meeting of the advisory board since the state reached an agreement with Enbridge almost two weeks ago that would pave the way for tunnel construction beneath the Straits of Mackinac.

State officials on Monday outlined details of the agreement, which will lead to construction of a shared “utility corridor” drilled 100 feet into bedrock below the lake bed, a project expected to take seven to 10 years and cost $350 million to $500 million. Enbridge has agreed to pay for the project, which depends on separate negotiations between Enbridge and the Mackinac Bridge Authority.

When talks between Enbridge and authority are complete, a final “highly technical agreement” will be put in place “that will talk about design, and then the building, and then the long-term operation and maintenance of a tunnel,” said Keith Creagh, director of the state Department of Natural Resources and co-chair of the advisory board.

The state maintains the Mackinac Bridge Authority has the legal right to oversee the construction of the pipeline since the definition of “bridge” in the statute governing the authority is broad and includes infrastructure such as tunnels, said assistant attorney general Robert Reichel. Nonetheless, legislation is being drafted that would clarify and cement that authority for the organization.

The state did not consult with the authority before announcing the plan, said Creagh, who added that such a conversation would be “inappropriate."

“I think we had to first figure out, was there an agreement to build a tunnel?” he said Monday.

Part of the state’s Oct. 3 agreement with Enbridge requires the utility have staff on hand to close the line within 15 minutes if waves measure six and a half feet for at least an hour and commence with the shutdown if waves measure at eight feet for at least an hour. The agreement expanded on a temporary requirement to shut down operations if waves exceed eight feet.

Shepler said he was on the water for 11 hours Sept. 21 and estimated the waves were anywhere between 10 and 12 feet tall. The state shut down the Mackinac Bridge that day because winds blowing across the bridge surface were in excess of 50 miles per hour.

Waves that day peaked at 7.8 feet, but mostly hovered around 6 and a half feet during the roughest periods, said Scott Rozanski, meteorologist for the National Weather Service in Gaylord.

The data was pulled from a buoy just west of the straits, Rozanski said, noting that wave heights could vary depending on which buoy the state and Enbridge rely on for measurements.

Shepler said he estimates there were other days with high waves as well, but “that day in particular rings in my mind that that would be the perfect opportunity to shut that thing down.".

Grosse Pointe lawyer Craig Hupp, a member of the advisory board, echoed Shepler's concerns, questioning whether the 8-foot threshold was too high when considering the problems it could pose to emergency response.

"A variety of the equipment they would use on the water, the higher the wave height the less effective the equipment is and there's certain wave heights above which the equipment doesn't' work," Hupp said.

The debate occurred as the The U.S. Coast Guard said Monday that ships at least 131 feet long can’t drop anchor in the Straits of Mackinac unless they have permission starting Oct. 31. The Coast Guard is making is an exception to the no-anchor zone if a boat has an emergency.

Gov. Rick Snyder in May approved an emergency rule barring anchor drops in the waterway after a tugboat anchor struck oil and electrical lines and caused an insulation spill.

eleblanc@detroitnews.com

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