The Michigan Supreme Court has instructed state regulators to reevaluate a critical permit that authorized the advancement of a proposed tunnel for an oil pipeline beneath a segment of the Great Lakes. This 6-1 ruling raises uncertainty about the future of Enbridge’s 73-year-old Line 5 pipeline, which transports petroleum from Superior, Wisconsin, to Sarnia, Ontario.
The contested section of Line 5 stretches six kilometers under the Straits of Mackinac, where Lakes Huron and Michigan converge. Enbridge’s plan involves placing the pipeline in a tunnel beneath the straits, while environmental advocates and Michigan Governor Gretchen Whitmer advocate for relocating the pipeline entirely due to concerns about potential devastating consequences of a spill in the Great Lakes region.
The Michigan Public Service Commission had approved the tunnel construction permit in 2023, prompting legal action from four Michigan tribal nations and multiple environmental organizations. The recent Supreme Court ruling highlighted the regulators’ failure to analyze the potential extension of the pipeline’s lifespan through the tunnel project, potentially leading to increased environmental harm.
Moreover, the court noted inconsistencies in the evaluation of alternatives to the pipeline and the lack of assessment regarding the tunnel’s impact on fishing, boating, and public trust rights in the Great Lakes area. Critics of the pipeline project argue that the proposed tunnel, a unique endeavor, would disrupt the Straits of Mackinac, a culturally significant site for Indigenous Anishinaabe tribes, during years of construction.
Enbridge expressed disappointment over the ruling, emphasizing the project’s prolonged review process over almost a decade and its purported benefits in bolstering environmental safeguards for the Great Lakes and ensuring energy reliability in the region. The company first proposed the tunnel concept nearly ten years ago following an incident where a ship anchor damaged part of the pipeline.
Governor Whitmer and other state officials have been actively seeking to halt the pipeline operation under the straits through separate legal proceedings since 2020. Opposition to the Line 5 project persists, with concerns about potential environmental damage and the unique challenges posed by running a major oil conduit beneath the Great Lakes.
