After a major spill in northern Wisconsin, caused when a runaway truck struck Enbridge’s Line 5 at a valve site in Iron County, Michigan Governor Gretchen Whitmer and the state’s environmental director are backing away from July permits, saying they must reexamine their approval under mounting legal pressure.

The reversal follows a Michigan Supreme Court ruling that struck down a key Public Service Commission permit, finding regulators conducted an overly narrow review and must now complete a broader analysis under the Michigan Environmental Protection Act that fully assesses the tunnel’s environmental harms and considers alternatives.

Whitmer drew scrutiny in July from tribes and Great Lakes advocates after the Michigan Department of Environment, Great Lakes and Energy, or EGLE, reissued wetlands and bottomlands permits for the Line 5 tunnel project. Enbridge had allowed its 2021 permit to expire, then reapplied with additional wetlands-survey data. The agency approved the application after a 16-month review.

Great Lakes groups and tribes said the decision undercut Whitmer’s earlier effort to shut down Line 5 and reduce spill risks in the Straits of Mackinac between Lakes Michigan and Huron.

Now Whitmer and EGLE Director Phil Roos say the court’s decision means the state has to take a fresh look at how that ruling affects the July tunnel permits, with Roos adding that construction of Enbridge’s Line 5 tunnel is already on hold until legal questions are sorted out.