MICHIGAN — The Trump administration has stepped into the legal fight over Enbridge’s aging Line 5 pipeline beneath the Great Lakes, contending that Michigan Gov. Gretchen Whitmer’s move to revoke the line’s easement almost five years ago clashes with U.S. foreign policy.
Line 5, in service since 1953, runs crude oil between Superior, Wisconsin, and Sarnia, Ontario. A 4.5-mile segment lies under the Straits of Mackinac, connecting Lake Michigan and Lake Huron. Environmental concerns intensified after Enbridge admitted in 2017 that protective coating gaps were known since 2014, and an anchor strike in 2018 heightened fears of a spill in the sensitive waters.
In November 2020, Whitmer ordered regulators to revoke the easement. Enbridge sued in federal court, and the pipeline has kept operating as litigation continues.
Trump DOJ position
Justice Department attorneys filed a brief on Sept. 12, saying Whitmer’s action sought to “globalize” Michigan’s authority and conflicted with the federal goal of maintaining energy flow with Canada. They argue the order also contradicts Trump’s 2024 executive orders stressing energy security as national security.
“Shutting down Line 5 could disrupt the energy supply chain, raise prices, and give leverage to hostile foreign actors,” DOJ lawyers wrote.
They also cited a 1977 U.S.-Canada treaty that prevents authorities from impeding cross-border pipeline energy flows and argued that only the federal government regulates pipeline safety, not states.
Michigan response
Whitmer’s attorneys counter that the state has authority under the public trust doctrine to protect natural resources. Michigan AG Dana Nessel’s office plans to respond in October, emphasizing that revoking the easement is a routing decision, not a safety regulation. They also argue private firms like Enbridge cannot use the treaty as a legal weapon.
Enbridge’s stance
Enbridge’s arguments align closely with the DOJ. Company spokesperson Michael Barnes pointed to the treaty provisions, saying neither states nor courts can unilaterally shut the pipeline.
U.S. District Judge Robert Jonker is set to hear arguments on Enbridge’s motion for summary judgment on Nov. 12.
Tunnel proposal
Enbridge has proposed a $500M tunnel to encase the straits segment, which would destroy wetlands and bat habitat but remove anchor-strike risks. Michigan regulators approved permits in December 2023, and the U.S. Army Corps of Engineers fast-tracked the final permit earlier this year. Environmental groups and Native American tribes are appealing the tunnel permits to the Michigan Supreme Court.
Broader legal battles
- 2019 lawsuit: Nessel filed to void the easement; the U.S. Supreme Court is deciding whether state or federal courts should handle it.
- Wisconsin dispute: A federal judge ordered Enbridge to shut down part of Line 5 crossing the Bad River Band’s reservation within three years. Enbridge appealed while proposing a reroute. Separate challenges to reroute permits continue with hearings into October.