Power outage forces Line 5 pipeline shutdown

Enbridge performs an external inspection of the pipeline near the Mackinac Bridge. Photo Courtesy of Enbridge

Enbridge Energy shut down the Line 5 pipeline for one day in mid-April because of a power outage caused by severe storms.

According to a company statement, the pipeline was shut down on April 15 due to a power outage at the Enbridge terminal in Superior, Wisconsin, as well as hazardous weather conditions in the Straits of Mackinac. Line 5 runs under the Straits in Michigan and provides the state with over 50 percent of its propane supply. On April 10, prior to the shutdown, Enbridge informed the state of three small dents in the pipeline caused by a ship anchor strike.

While Enbridge reported no significant damage, the state demanded its own experts verify the information, according to the office of the governor. The November 2017 agreement between the state and Enbridge called on the company to fast track studies showing the feasibility of constructing a tunneled pipeline under the Straits as an alternative to the aging pipeline. The study is expected to be completed in June.

According to the office of the governor, if the study shows a tunneled pipeline is physically possible and construction would not cause significant environmental damage, Gov. Rick Snyder will move to require Enbridge to construct the tunnel and decommission the existing Line 5.