Michigan Supreme Court Rejects Permit for Line 5 Tunnel Under Straits of MackinacAugust 2, 2026Associated Press / news@whmi.comThe Michigan Supreme Court has ordered state regulators to reconsider a key permit that allowed a planned tunnel to carry an oil pipeline under part of the Great Lakes to move forward. The part of the pipeline in question, called Line 5, runs for 4 miles (6 kilometers) along the bottom of the Straits of Mackinac where Lakes Huron and Michigan meet. Gretchen Whitmer want to move the pipeline away from the waterway altogether saying a spill would be catastrophic to the Great Lakes and surrounding area. The Michigan Public Service Commission granted a permit to build the tunnel in 2023. Enbridge proposed the pipeline tunnel nearly a decade ago around the time a ship anchor dented part of the line.