Canada · Industrial projects
What the Trans Mountain expansion added to Canada’s oil network
The Trans Mountain expansion entered service in May 2024 and lifted total system capacity to 890,000 barrels a day. The Canada Energy Regulator reported average utilisation of 82% from June 2024 through June 2025.
Sources checked
- 01System capacity
890000 · Barrels per day following expansion Source 1
- 02Committed capacity
707500 · Barrels per day available to long-term committed shippers Source 1
- 03Uncommitted capacity
182500 · Barrels per day available on a monthly basis Source 1
- 04First full month’s throughput
704000 · Average barrels per day, June 2024 Source 1
- 05Highest throughput in the snapshot
793000 · Average barrels per day, March 2025 Source 1
- 06Average system utilisation
82% · June 2024 to June 2025 Source 1
Committed and uncommitted allocations add up to the expanded system’s stated capacity.
The expansion changed the export network
The regulator says the project nearly tripled Trans Mountain capacity and lifted total western Canadian crude export pipeline capacity by 13%. It estimates that export capacity to ocean-access terminals in western Canada rose by about 700%. Those percentages use different starting networks. Source 1
Use built up after the opening month
The expanded system started ramping up in May 2024. Throughput reached 704,000 barrels a day in June and a high of 793,000 in March 2025. The regulator reported system utilisation of 76% in December 2024 and 89% in March 2025. Source 1
Contracts reserve most of the available space
About four-fifths of capacity is reserved for committed shippers under long-term take-or-pay contracts. The regulator reports those shippers used about 99% of their reserved capacity on average during the measured period. The 82% overall measure also includes space available to uncommitted shippers. Source 1
Marine departures indicate access to more markets
The regulator counted an average of 23 departures a month at Westridge between June 2024 and July 2025. It also found Canadian crude exports to countries other than the United States more than tripled after the expansion started. The marine departures and the export statistics cover different populations. Source 1