The U.S. Supreme Court has upheld Michigan’s position in a case involving the closure of a segment of an old pipeline under a Great Lakes channel, ruling that the lawsuit will remain in state court. Justice Sonia Sotomayor, speaking for the entire court, stated that Enbridge, a Calgary-headquartered energy firm, had waited too long to attempt to transfer the case to federal court.
The legal battle concerns a pipeline that has transported crude oil and natural gas liquids between Superior, Wisconsin, and Sarnia, Ontario, since 1953. Michigan Attorney General Dana Nessel initiated the lawsuit in state court in June 2019 to invalidate the easement enabling Enbridge to operate a 6.4-kilometer section of the pipeline beneath the Straits of Mackinac, connecting Lake Michigan and Lake Huron.
In June 2020, Judge James Jamo of Ingham County granted Nessel a restraining order to halt pipeline operations, although Enbridge was allowed to resume activities after meeting safety standards. Enbridge shifted the case to federal court in 2021, arguing its impact on U.S. and Canadian trade. However, a three-judge panel from the 6th U.S. Circuit Court of Appeals sent the case back to Jamo in June 2024, citing Enbridge’s failure to meet a 30-day deadline for changing jurisdictions.
The contentious pipeline, known as Line 5, has raised concerns about potential ruptures in the section beneath the straits, especially after Enbridge engineers disclosed gaps in the protective coating in 2014. A boat anchor caused damage to the section in 2018, heightening fears of a spill. In 2020, the Michigan Department of Natural Resources, under Governor Gretchen Whitmer, revoked the easement for Line 5 at the straits, prompting Enbridge to launch a separate federal lawsuit challenging the revocation.
Enbridge is currently seeking permits to encase the pipeline section under the straits in a protective tunnel. While the Michigan Public Service Commission approved the necessary permits in 2023, Enbridge still requires consent from the U.S. Army Corps of Engineers and the Michigan Department of Environment, Great Lakes, and Energy.
The pipeline is also embroiled in a legal battle in Wisconsin, where a federal judge in Madison ordered Enbridge to shut down a portion of Line 5 that traverses the Bad River Band of Lake Superior’s reservation within three years. Enbridge has proposed rerouting the pipeline around the reservation and has appealed the shutdown order to the 7th U.S. Circuit Court of Appeals.