POLAR has another ally in Brandon Township, a community of 15,000 located 50 miles north of Detroit. The pipeline passes through the township, and Enbridge has refused to follow some of the local ordinances and requests for extra safety measures.

In legal filings, Enbridge has said that it follows federal pipeline regulations, which preempt state and local ordinances.

But the U.S. Department of Transportation has said it has no control over state rules and regulations. Charles Ten Brink, a law professor from Michigan State University, told InsideClimate News last month that federal law doesn't always supersede local ordinances.

On Nov. 5, two days before the federal hearing, Brandon Township asked to intervene in the case. The judge's ruling on Tuesday did not address whether the township could join POLAR as a party in the lawsuit.

Brandon Township Supervisor Kathy Thurman said the board of trustees will meet Thursday night to discuss whether and how to continue the township's involvement.

Axt emphasized that the lawsuit is not about opposing a pipeline, but rather about forcing Enbridge to abide by local regulations. "I think we can all agree the existing laws and permits should all be followed, whether you're building a pipeline, a house, a road, or a dog house.

Click here to view a map of the Line 6B replacement project.

InsideClimate News reporter David Hasemyer contributed to this report.