Minnesota utility regulators Tuesday authorized their final go-ahead for Enbridge to build its controversial $2.6 billion oil pipeline across northern Minnesota.

That leaves the Canadian company on the brink of beginning work, only needing a more routine stormwater permit from the Minnesota Pollution Control Agency (MPCA).

The state Public Utilities Commission (PUC) on Tuesday gave its OK for construction to begin. The PUC’s action was expected. It approved the overall project in February.

The PUC’s action came a day after the U.S. Army Corps of Engineers issued a water quality-related construction permit for the project. The MPCA issued a parallel permit earlier this month.

The MPCA stormwater permit is expected within the next week or so. Calgary, Alberta-based Enbridge plans to start construction on the 340-mile pipeline right after that.

The new pipeline, a replacement for Enbridge’s aging and corroding Line 3, has been winding through the state regulatory process for six years.

The PUC, the state’s primary regulator of pipelines, approved the pipeline in February for the second time after a court sent it back to the panel for changes in the project’s environmental impact statement.

Enbridge has said the new pipeline is a critical safety enhancement. Environmental groups and some Indian bands have said the pipeline — which follows a new route — will open a new region of pristine waters to the prospect of oil spills, as well as exacerbate climate change by allowing for more oil production.