Pipeline Work Destroyed Salmon Habitat, Puts Orcas at Risk, Scientists Say

Expansion of the Trans Mountain pipeline could spell trouble for salmon populations and the orcas that rely on them for food, experts say.
Biologist Mike Pearson found that poor work on the Trans Mountain pipeline made a local stream unsuitable for chum salmon. File photo: Shutterstock
Biologist Mike Pearson found that poor work on the Trans Mountain pipeline made a local stream unsuitable for chum salmon. File photo: Shutterstock

Shoddy work on a section of the Trans Mountain pipeline in Chilliwack, British Columbia has “degraded” a local coho and chum salmon habitat, says a BC-based biologist with more than 30 years’ experience.

The biologist, Mike Pearson, says the work is a warning sign of what might happen with future pipeline developments, and could have greater downstream impacts on other wildlife, such as orcas, if Trans Mountain adopts similar methods for other stream systems.


Pearson undertook an assessment of Stewart Creek in December 2018 and filed it to the National Energy Board (NEB) later that month. The report found that the fix (placing concrete blocks and crushed gravel on top of a exposed pipe) made the stream unsuitable for salmon.

The smooth concrete blocks meant most of the gravel was washed away just months after it was added, leaving no places for salmon to hide or bury their eggs, or for the salmon’s food source (aquatic invertebrates) to grow.

“No consideration is given to restoring or mitigating impacts on habitat,” Pearson told me over the phone, adding that he’s seen a lack of consideration for wildlife habitats at other Trans Mountain project sites as well.

He says the site is highly visible to the public and logistically simple compared to other stream systems, so there was no excuse for not getting it right.

“If under those circumstances sufficient care isn’t going to be taken…then I’m concerned,” Pearson told Motherboard.

Pearson says that salmon populations, and the orcas that rely on them as as a food source, could be at risk in the future if other streams receive the same treatment if the pipeline expansion gets the go-ahead.

In a statement released Wednesday on its website, Trans Mountain Corp. said Pearson’s comments were “inaccurate.” Stewart Creek construction plans were approved by relevant regulatory agencies, and third-party environmental professionals assessed the work, the company added.


“We are committed to protecting fish and fish habitat, and we push to continuously improve our performance and minimize the impacts of our activities today and long into the future,” Trans Mountain Corp. said.

Lack of food is the biggest threat to resident orcas, which occupy the area between Vancouver Island and northern Washington, according to Lance Barrett-Lennard, director of the marine mammal research program at Ocean Wise.

Chinook salmon makes up the majority of the orcas’ diet, but Barrett-Lennard says that chum salmon is a key food source in September and October and can make up for shortages in other salmon species. Barrett-Lennard notes that most years whales are too thin because they’re not getting enough to eat.

In an interview, Barrett-Lennard said that both Canadian and United States governments are investing millions of dollars into salmon habitat restoration while not doing enough to properly mitigate damage to those same habitats.

“We can pour money into one side of a problem and not do the obvious things on the other side,” he told me over the phone.

Read More: Canada and the US Have Failed the Orca for a Decade

Orcas face other threats directly related to the pipeline: collisions with vessels (oil tanker ships are expected to increase sevenfold with the pipeline expansion), a reduced ability to echolocate because of vessel noise, and contamination from oil spills.

Environmental groups including Stand.earth and Ecojustice say the NEB’s latest recommendations for the Trans Mountain pipeline, such as making a plan to evaluate the environmental impact of the pipeline and updating the federal oil spill response requirements, lack teeth.

“The way they’ve put [the recommendations] forward they wouldn’t be binding to the project; they’re just suggestions of what the federal government might explore,” Ecojustice’s lawyer Dyna Tuytel told Motherboard.

In its most recent submission to the NEB, Trans Mountain Corp. asks the board to disregard many of the arguments made by interveners, based on alleged lack of evidence or overinflation. In an earlier submission Trans Mountain Corp. states that significant environmental effects are justified because of the importance of the project.