A Canadian federal court of appeal has overturned the City of Ottawa’s approval of the Trans Mountain pipeline expansion, which is reported to triple the flow of oil from Edmonton, Alberta, to Kamloops, British Columbia.

In a unanimous decision, the federal court said the Canadian Government did not take into account the concerns of indigenous groups when supporting the project. It also found that the National Energy Board (NEB) failed to properly consider the impact of increased tanker traffic brought by the project.

Due to the court ruling, Kinder Morgan is compelled to suspend construction of 1,150km of the pipeline until the NEB and the government can probably comply with the court’s demands, a potentially lengthy process.

At the time of Ottawa’s approval, Greenpeace Canada’s Mike Hudema told Offshore Technology: “These approvals don’t really change the fate of this problem-plagued pipeline that will never be built. This pipeline still faces a litany of legal challenges, crumbling economics and a ground resistance that continues to grow by the day. The wildfires and record heatwaves should be the last warning signal we need that we can’t be building new fossil fuel infrastructure.”

While supporters of the project said the pipeline expansion will help Canada to reach Asian markets, thus reducing the nation’s reliance on US exports, environmentalist groups have protested against its construction, highlighting many negative consequences.

"Thankfully, the court has stepped in where Canada has failed to protect and respect our rights and our water."

The potential for oil spills, growing tanker traffic, and the increased danger to Canada’s orca population that already faces extinction, have all been cited as reasons to scrap the Trans Mountain pipeline expansion.

Campaigners and indigenous groups against the pipeline applauded the ruling. Coldwater Indian Band chief Lee Spahan said: “Thankfully, the court has stepped in where Canada has failed to protect and respect our rights and our water.”

After the ruling, Hudema told the Guardian: “Now it’s time for Prime Minister Trudeau to read the writing on the wall, dump this pipeline and shift the billions of public dollars slated for this problem-plagued project into Canada’s renewable energy economy.

“This summer’s fires, floods, and choking smoke make it impossible to ignore the rising costs of climate inaction, so the prime minister should welcome the opportunity created by today’s ruling to get on the right side of history.”

In response, Canada’s finance minister Bill Morneau noted that the government still plans to move ahead with the project, saying: “We believe this project is in the national interest, we believe that it’s critically important for our economy, critically important to allow us to get to international markets.”