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Heavy ReadingThe WCSB supply letter

Sections

Supply

The physical barrel: takeaway capacity, what grade it is, and when it goes offline for maintenance.

Executive call

• Tradable supply averages 4,286.2 kb/d from Nov 2026 onward, +190.3 kb/d versus the Oct 2026 context month (4,095.9 kb/d).
• Sep 2026 is the heaviest modeled maintenance month at 310.0 kb/d offline:
  • Horizon 35-day turnaround
  • Syncrude Coker 8-2 turnaround
  • Imperial Cold Lake 3Q/4Q 2026 turnaround
• No public-confirmed maintenance sits in the model math from Jan 2027 onward:
  • April 2027: Primrose/Wolf Lake CADENCE-MODELED turnaround (-26 kb/d, weak-signal flag)
  • September 2027: MacKay River CADENCE-MODELED turnaround (-12 kb/d)
• Largest projected month-to-month supply moves:
  • Oct 2026 to Nov 2026: +365.0 kb/d
  • Dec 2026 to Jan 2027: -347.9 kb/d
  • May 2027 to Jun 2027: +270.9 kb/d
• Implied storage change ranges from a high of -331.6 kb/d in Apr 2027 to a low of -512.2 kb/d in Feb 2027 (positive = build into commercial storage, negative = draw).

All figures kb/d, computed from the model tables. Full call: the Dashboard.

Egress

How full the pipes are: available capacity by system against what actually flowed. The TMX expansion step is structural: the capacity series itself steps up in May 2024.

Egress is running 94% full: 272 kb/d of spare capacity in Jun 2026

Enbridge capacityKeystone capacityTrans Mountain capacityTotal throughput

Download CSV CSV · CER open data (throughput + capacity), pulled 2026-09-22

Supply by type

What kind of barrel the WCSB produces: heavy, light, medium, and synthetic. The window runs from AER actuals through the nowcast into the model forecast.

Into Dec 2027: biggest add Heavy +36 kb/d; biggest drag Medium -2 kb/d

HeavySyntheticLightMediumTotal tradable supply

Download CSV CSV · AER ST3 actuals through 2026-07 (pulled 2026-09-22); Aug-Sep 2026 nowcast estimated; forecast model build 2026-09-22

Biggest movers

The largest month-over-month changes in the latest published actuals. Monthly data — this is not a weekly movers table.

Asset	Type	Jun 2026	Jul 2026	Change kb/d	Change %	z-score	Signal
Foster Creek (Cenovus)	Project	235.5	310.7	+75.2	+31.9%	+2.5	signal
Christina Lake (Cenovus)	Project	376.2	403.8	+27.6	+7.3%	+0.6
Primrose and Wolf Lake (CNRL)	Project	91.9	113.5	+21.6	+23.5%	+2.4	signal
Cold Lake (Imperial)	Project	203.2	194.3	-8.9	-4.4%	-0.8
Sunrise (Cenovus)	Project	80.6	86.2	+5.6	+6.9%	+0.4
Condensate	ST3 line	97.3	91.7	-5.6	-5.8%	-0.9
Narrows Lake (Cenovus)	Project	96.2	101.6	+5.4	+5.6%	+1.5
Surmont (ConocoPhillips)	Project	172.2	167.8	-4.4	-2.6%	-0.6
Kirby (CNRL)	Project	73.4	70.1	-3.3	-4.5%	-1.1
Jackfish (CNRL)	Project	131.9	128.8	-3.1	-2.4%	-0.2

A z-score measures how unusual this month's move is for that specific asset. A score of 2 means the move was about twice the asset's typical monthly swing over the past year. Big assets post big raw moves all the time, so the raw number alone misleads; the score separates a real signal from normal noise, and rows marked signal moved at least twice their normal monthly range.

Vintage: AER ST3 actuals, Jun 2026 to Jul 2026 (pulled 2026-09-22). Monthly source: these are month-over-month changes in published actuals, not weekly moves. Universe: 22 in-situ project leaves, 13 mined/upgrader plant leaves, and the 5 conventional ST3 native lines; aggregates, decomposed lines, and grade derivations are excluded so no barrel counts twice.

Maintenance outlook

Forward offline volumes from the maintenance dataset: company-stated turnarounds where they exist, cadence-modeled where they don't.

Sep 2026 is the heaviest maintenance month in the forward calendar: 310 kb/d offline

Download CSV CSV · forward maintenance calendar 2026-09-22; modeled at the leaves 2026-09-23

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