The Minnesota Court of Appeals on Tuesday denied a petition from two Ojibwe bands to halt construction of Enbridge's controversial Line 3 replacement project across northern Minnesota.

In December, the Red Lake Band of Chippewa and the White Earth Band of Ojibwe petitioned the appellate court to suspend state regulators' approval of Enbridge's new $2.6 billion pipeline and stop construction.

The tribes claimed that without a stay of Line 3's construction "their treaty-protected interests in the land, waters, plants, animals and environment" would be destroyed or damaged by construction — as would their cultural and religious rights.

Enbridge claimed there was "no legitimate basis" for the tribes' filing, saying the petition failed "to recognize the exhaustive and meticulous review" of the project.

In a statement, Enbridge said it was "pleased" with the appellate court's decision, "but not surprised." One construction union leader, Kevin Pranis with the Laborers Union, said he was "relieved, and vindicated."

The two Ojibwe bands and environmental groups blasted the court's decision.

"The Red Lake Nation is very disappointed that the Minnesota Courts place more weight on the employment of out-of-town pipeline workers than it does the irreparable harm that construction causes to our water, wild rice and forests," Joe Plumer, attorney for Red Lake Nation, said in a statement.

Calgary, Alberta-based Enbridge started construction in early December and expects to complete the pipeline by the end of September. Line 3 navigated the regulatory process for six years. The Minnesota Public Utilities Commission (PUC) approved the project in February 2020 for the second time, after the Minnesota Appeals Court asked for a more detailed environmental review.

The Red Lake and White Earth bands, along with several environmental groups and the Minnesota Department of Commerce, all appealed the PUC's second approval.

The appellate court has scheduled oral arguments for late March, with a decision possibly coming months later. The court said that with its Tuesday decision it is not expressing an opinion on the merit of the issues in the case. The tribes have argued that without a stay of the PUC's decision, their claims would be made moot by the pipeline's construction.

By law, the tribes had to first ask the PUC itself to stay its own approval of Line 3. The PUC acknowledged that the tribes could be harmed without a stay, but said that with a stay, Enbridge and the roughly 4,000 workers building the pipeline could be harmed. In denying the stay, ultimately the PUC said the Minnesota Appeals Court — if it rules in favor of pipeline opponents — could eventually shut down operation of Line 3 even if it has already been built.

"The commission's [stay] decision is not an abuse of discretion," the appellate court ruled Tuesday.

The court also acknowledged possible harm to either side regardless of the decision. But that does not "require this court, which is required to give deference to the commission, to override the commission's decision."

The Red Lake and White Earth bands also have asked a federal court to halt construction of Line 3, saying the U.S. Army Corps of Engineers failed to adequately address several environmental issues when it approved a key water quality permit. That decision is pending.

Environmental groups and some Indian bands have said the pipeline 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.

Enbridge has said the new pipeline is a critical safety enhancement. The current Line 3 is so corroded it is running at only half of capacity.

Mike Hughlett • 612-673-7003