Posted on February 27, 2026
Dredging the shipping channel would allow for oil tankers calling on Trans Mountain’s Westridge terminal to fill to their full capacity, but the project faces continued First Nations opposition and raises environmental concerns
The Port of Vancouver has started the clock on the first part of an environmental review process for a harbour dredging project that would boost the potential for increased oil shipments from the Trans Mountain pipeline’s Westridge Marine Terminal in Burnaby.
Dredging along the edges of the shipping channel at second narrows, which is just to the east of the Iron Workers Memorial Bridge, would shave peaks off the sea bottom that prevent tankers that call on the terminal from loading to full capacity.
It’s a project that has the backing of Prime Minister Mark Carney as part of his drive to diversify Canadian trade and has the begrudging support of B.C. Premier David Eby, who has held out on expanding the pipeline’s existing capacity as an acceptable alternative to building a new bitumen pipeline to B.C.’s North Coast.
This week, the port’s governing body, the Vancouver Fraser Port Authority, opened a public comment period for an environmental review process with the Impact Assessment Agency to determine whether dredging “is likely to cause significant adverse environmental effects.”
Its timeline would see its review carry on through 2026, with work to be completed in 2027, or 2028 at the latest.
The project’s purpose is “to boost trade capacity at the Port of Vancouver in support of national exports to overseas markets,” said Charlotte Olson, the port authority’s acting vice-president of infrastructure in a statement. “We anticipate dredging and associated works could start later this year, pending regulatory approval.”
To gain that approval, however, they will have to navigate the concerns of the Tsleil-Waututh First Nation, which has already raised issue with the proposal and still disapproves of the expanded Trans Mountain pipeline facilities, which would be the first beneficiaries of a deepened second narrows.
No one from the Tsleil-Waututh Nation’s leadership was available for comment Wednesday, but in a statement from earlier in 2025, former chief Jen Thomas said the nation maintains “a sacred, legal obligation to protect, defend and steward our inlet.” In the statement, Thomas issued a reminder that the Tsleil-Waututh hold “constitutionally protected” title and rights in the area and “cautions those who speak as though this project has been pre-approved.”
On paper, the proposed project looks small. Dredging along the edges of the channel would disturb some 25,000 cubic metres of material in a total area of less than two hectares, the size of about three soccer fields, according to the port’s project web page.
Material expected to be removed during dredging — sand, gravel sandstone and boulders — would be disposed of at a facility on land designed to receive marine sediments and the port estimates the total amount will represent less than one per cent of the amount it typically dredges up in its annual maintenance program.
However, to the Tsleil-Waututh, “(a) proposal to dig up the seabed, which is culturally a part of us, is a very serious concern,” Thomas said in the nation’s earlier statement.
Dredging raises environmental concerns ranging from disturbing toxic pollutants that have concentrated in sediments on the sea floor to blocking sunlight that interrupts the growth of phytoplanktons in the marine foodweb, according to news reports.
What’s at stake, from the perspective of international trade, is the capacity to expand oil exports from Canada’s West Coast.
The tankers that call on Westridge terminal are a class called Aframax, that are up to 255 metres long carrying up to 755,000 barrels of oil. However, those tankers can only fill to 75 to 80 per cent of capacity with the second narrows’ existing depth. Filling to 100 per cent would allow fewer ships to carry the same volume of oil, allowing for an expansion of exports.
The federal government took over Trans Mountain in 2018, for a price tag of $4.5 billion, to complete the twinning of its existing pipeline, whose total cost came in at $34 billion. Twinning the facility almost tripled its capacity to 890,000 barrels of oil per day, which has helped fuel a dramatic increase in Canada’s offshore exports.
Last September, the port reported that shipments of mostly diluted bitumen from Alberta’s oilsands hit 11.6 million tonnes in the first half of 2025, a 365 per cent increase from the same period of 2024, when the expanded pipeline first started operations.
And Trans Mountain is working on projects to “optimize” the expanded facilities to increase its capacity by up to another 500,000 barrels per day.
