Trans Mountain Plans Three-Stage Capacity Push to 1.2 Million Barrels as US Refiners Watch Canadian Supply
Trans Mountain Corp. is pursuing three capacity expansions that together could lift throughput to 1.2 million barrels daily by 2029, as US-Canada trade tensions cloud southbound crude flows.
US refiners were confronting a looming supply shortfall from Canada, their biggest foreign crude supplier, Rigzone reported on August 22 (2026-08-22). Canada delivers more than 4 million barrels a day across the US border, and any sustained reduction in those flows would leave Gulf Coast and Midwest refiners scrambling for replacement barrels in a market where spot availability is already thinning.5
Trans Mountain's capacity expansion adds a Pacific dimension to that supply picture. The expanded pipeline, which runs from Alberta's oil sands to a marine terminal in Burnaby, British Columbia, reached its full carrying capacity of 890,000 barrels daily for the first time in June 2026, Bloomberg reported. Asian demand pulled hard enough during that month that shipment requests ran above available capacity.2
Trans Mountain Corp. chief executive Mark Maki has laid out three separate growth phases. The fastest: deploying drag reduction agents in the existing pipe would add 90,000 barrels a day without new construction, Maki said, as quoted by Bloomberg. The company simultaneously launched an open season in early April 2026 seeking takers for a further 72,000 barrels of daily capacity, which Maki said would push the share of throughput held under long-term contracts to 90% from 80%.1
The longer-horizon addition is the Mainline Optimization Project, designed to add 210,000 barrels daily by the end of 2028. Maki said last year that total pipeline capacity could reach 1.2 million barrels daily by 2029 — about 35% above the June 2026 ceiling.1
Locking more capacity into long-term agreements tightens the commercial logic for further investment but shrinks what is available for spot sales. As the contracted share moves toward 90%, any producer or trader seeking pipeline access without a pre-existing deal will face a narrower window. The open season results — which Trans Mountain has not yet disclosed publicly — will show how much appetite Asian buyers have for multi-year commitments at current ICE Brent crude front-month levels near $99 a barrel.1
Trade policy is running in parallel with the expansion agenda. Senior Canadian officials were in last-minute talks in August 2026 to avoid new 50% US tariffs, with Washington having scheduled the levies for August 19 (2026-08-19) on roughly $20 billion of Canadian goods, from dairy products to electronics, according to Foreign Policy. A tariff regime that raised friction on southbound crude flows would push Canadian producers further toward Trans Mountain's Pacific route and accelerate demand for whatever capacity the open season delivers.4
Global supply disruptions provide backdrop. Ukrainian drone strikes have hit Russian refining infrastructure at multiple sites, with the Moscow oil refinery halting following an attack on June 16 (2026-06-16). The Caspian Pipeline Consortium stopped receiving oil from July 20 (2026-07-20) after attacks on tankers at its Black Sea terminal. Those events tighten aggregate supply and support the price case for moving Canadian barrels to Asian buyers rather than selling them into the US market at a discount.3
WTI crude front-month was trading at $94.20 a barrel on September 9 (2026-09-09), running about $5 below ICE Brent front-month at $99.30. For Canadian heavy crude moving through Trans Mountain, the economics of Pacific routing depend less on the WTI outright than on the spread between US and Asian destination prices and on what freight and terminal costs look like on a per-barrel basis — figures Trans Mountain has not disclosed in the current open season.2,5
The drag reduction agent programme carries no permitting exposure and is the nearest thing Trans Mountain has to a guaranteed near-term capacity gain. How fast it rolls out, and how much committed volume the open season attracts, are the two numbers that give the 2029 target its credibility. Until those figures are public, 1.2 million barrels a day remains an aspiration rather than a contracted outcome.1