Michigan’s Supreme Court sent a key permit for Enbridge Inc.’s (TSX: ENB) Line 5 tunnel project back to state regulators Friday, ruling that they never properly weighed how the project could extend the aging pipeline’s life and the environmental risks that come with it. Six of the court’s seven justices sided against the commission, with Justice Elizabeth Welch authoring the majority opinion. Re: Line 5 tunnel project"The Michigan Supreme Court ruled Friday that when they granted the permit, regulators failed to consider if the tunnel project will extend the lifetime of the pipeline, resulting in more harm to the environment." Northern Shield pipeline… pic.twitter.com/dOyprMoS9D — Rory Johnston (@Rory_Johnston) August 2, 2026Enbridge unveiled the tunnel plan back in 2018, budgeting $500 million and estimating four years to build it. The tunnel would bury a roughly four-mile stretch of Line 5 that currently runs along the lakebed where Lake Michigan and Lake Huron meet.