Kinder Morgan's appeal to the National Energy Board after failing to get the permits it needs from the City of Burnaby, B.C., is just the first of what will likely be many legal challenges facing its Trans Mountain pipeline project in the coming months, according to one legal expert.

Jocelyn Stacey, an assistant law professor at the University of British Columbia, says an interprovincial pipeline like Trans Mountain falls under federal jurisdiction, and a project determined to be in the national interest would be subject to federal laws, overriding any contrary provincial or municipal laws.

But even though the project has already been granted federal approval by the NEB, it still faces strong local opposition from municipalities, First Nations and activists.

"There's a lot of constitutional litigation that's going to come out of the Trans Mountain pipeline," Stacey said.

"I think everybody who's been watching this from a legal perspective has expected this at some point."

Surprising timing

While Stacey isn't surprised that Kinder Morgan is appealing to the NEB, she is surprised by the timing of the appeal.

She noted that Trans Mountain's filing with the NEB was submitted only 10 days after applying to the City of Burnaby for the permits in question, and that its permit applications were, by Trans Mountain's own admission, incomplete.

"It seems to me that, based on what Trans Mountain is saying in these submissions, that its own claims that the delays are unreasonable seem quite exaggerated," Stacey said.

Derek Corrigan, mayor of Burnaby and a vocal opponent of the pipeline, called Trans Mountain's delay claims "insulting" and told CBC News last week that the city is simply doing its due diligence.

Kinder Morgan has not made a spokesperson available to CBC News, but said in a statement last week that it has been working "in good faith" with the city.

Long road ahead

Kennedy Stewart, NDP MP for Burnaby-South, also rejected the notion the city is intentionally delaying the permitting process.

"I think Mayor Corrigan is just doing his job, like all us residents of Burnaby expect, and I fully support his approach here," Stewart said.

Like Stacey, Stewart expects the legal battle to continue, citing polls that show firmly divided public support for the pipeline in B.C.

"We were told that this pipeline would not proceed without consent, [but] I don't think there's enough consent here to proceed, and you're going to see [legal challenges] all the way through this process," he said.

He also noted five people were arrested on Saturday for protesting the project, saying lines in the sand are already being drawn.

"That is the first real sign that the Trudeau government is willing to arrest people to facilitate the construction of this pipeline, and I think it's going to make people pause, and they'll really have to pick a side," Stewart said.

With files from CBC Radio One's The Early Edition.