Projects / Leismer

Leismer

Athabasca Oil Corporation
Pattern-indicated maintenance: May 2027 (indicator only, no volume in model math)SAGDATH

OperatorAthabasca Oil Corporation
TypeSAGD
TickerATH
ST53 schemeLeismer
DescriptionLeismer is a steam-assisted gravity drainage (SAGD) oil sands project in the Athabasca region, operated by Athabasca Oil Corporation. It is undergoing an expansion to 40,000 bbl/d by end of 2027.
Source: Athabasca Oil Corporation, Athabasca Oil Announces its 2026 Budget Focused on Production and Cash Flow Per Share Growth, via GlobeNewswire, 2025-12-11
StatusOperating. The 40,000 bbl/d expansion is under construction; a later phase (Phase 1) was not sanctioned as of Q2 2026.
Source: Athabasca Oil Corporation, Q2 2026 press release, 2026-07-29
Nameplate capacityExpansion targets 40,000 bbl/d of production by end of 2027, on a ~$300 million expansion project at about $25,000/bbl/d capital efficiency.
Source: Athabasca Oil Corporation, Athabasca Oil Announces its 2026 Budget Focused on Production and Cash Flow Per Share Growth, via GlobeNewswire, 2025-12-11
Start-up / phasesnot tracked in the public data used here
Ownership / JV splitAthabasca Oil Corporation owns 100% and operates Leismer.
Source: Athabasca Oil Corporation, Athabasca Oil Announces its 2026 Budget Focused on Production and Cash Flow Per Share Growth, via GlobeNewswire, 2025-12-11
Product and dispositionBitumen: flexible disposition, dilbit to market or upgrader feed (economically optimized)
Source: Dashboard grade-layer panel (leaf mapping lineage); disposition defaults from annotations/maintenance_disposition_history.md
Process / technologySAGD.
Source: Athabasca Oil Corporation, Athabasca Oil Announces its 2026 Budget Focused on Production and Cash Flow Per Share Growth, via GlobeNewswire, 2025-12-11
Froth treatmentnot applicable (in-situ / upgrading)
Interconnectsnot tracked in the public data used here
Growth / expansionsThe $300 million expansion project includes bringing on twelve new wells at Pads L10 and L11, adding two steam generators, heat exchangers, and increased fluid handling capacity. The expansion was expected to be substantially complete at end of 2026, with production growth to 40,000 bbl/d by end of 2027; capital and schedule were on track with original expectations.
Source: Athabasca Oil Corporation, Athabasca Oil Announces its 2026 Budget Focused on Production and Cash Flow Per Share Growth, via GlobeNewswire, 2025-12-11

A later Leismer Phase 1 had not yet been formally sanctioned and awaited fiscal-framework confirmation as of Q2 2026; this is distinct from the already-underway 40,000 bbl/d expansion.
Source: Athabasca Oil Corporation, Q2 2026 press release, 2026-07-29
Company-disclosed maintenanceA three-week facility turnaround was completed in May 2026 (four-year interval); all tie-ins for the expansion project were also completed during it. The new well pairs began steaming after the turnaround.
Source: Athabasca Oil Corporation, Athabasca Oil Announces its 2026 Budget Focused on Production and Cash Flow Per Share Growth, via GlobeNewswire, 2025-12-11
Operating costsnot disclosed in reviewed sources

Blank "not tracked" cells are facts not present in the public data used here. They are labeled, never estimated. Filing-sourced facts carry their document name and date; where sources disclose multiple bases for one figure, all are shown.

Production

32.6 kb/d
latest actual, Jul 2026 (Leismer (Athabasca))
35.6 kb/d
12-month forecast average, Oct 2026 to Sep 2027
Leismer (Athabasca) monthly production Leismer (Athabasca) monthly production kb/d 0.0 12.5 25.0 37.5 50.0 Aug 25: 35.1 kb/d Sep 25: 35.4 kb/d Oct 25: 34.6 kb/d Nov 25: 33.7 kb/d Dec 25: 33.8 kb/d Jan 26: 34.5 kb/d Feb 26: 34.2 kb/d Mar 26: 32.7 kb/d Apr 26: 32.3 kb/d May 26: 7.5 kb/d Jun 26: 30.0 kb/d Jul 26: 32.6 kb/d Aug 26: 33.0 kb/d Sep 26: 32.7 kb/d Oct 26: 33.8 kb/d Nov 26: 33.7 kb/d Dec 26: 34.0 kb/d Jan 27: 32.5 kb/d Feb 27: 33.1 kb/d Mar 27: 33.8 kb/d Apr 27: 34.6 kb/d May 27: 36.0 kb/d Jun 27: 37.9 kb/d Jul 27: 38.8 kb/d Aug 27: 39.4 kb/d Sep 27: 39.7 kb/d 39.7 Aug 25 Oct 25 Dec 25 Feb 26 Apr 26 Jun 26 Aug 26 Oct 26 Dec 26 Feb 27 Apr 27 Jun 27 Aug 27 Sep 27
Vintage: AER ST53 actuals through 2026-07 (ST39 through 2026-05), pulled 2026-09-22; Aug-Sep 2026 nowcast estimated, built 2026-09-23; forecast built 2026-09-22. Solid orange shading marks months with modeled maintenance on this series. Dashed shading marks pattern-indicated months (indicator only, no volume in the model math). Series: Leismer (Athabasca).
Actuals (AER)Nowcast (model est.)Forecast (model)Modeled maintenance monthPattern-indicated (not in model math)
Latest actuals (kb/d)
SeriesFeb 2026Mar 2026Apr 2026May 2026Jun 2026Jul 2026
Leismer (Athabasca)34.232.732.37.530.032.6
First forecast months (kb/d)
SeriesOct 2026Nov 2026Dec 2026Jan 2027Feb 2027Mar 2027
Leismer (Athabasca)33.833.734.032.533.133.8

Full 26-month table with drill-down lives in the trading dashboard. Blank cells are months AER has not published yet, not zeros.

How to read Leismer (Athabasca): May dip is seasonal (May flagged 4 of 9 years). Next routine turnaround on the stated 4-year frequency, around 2030. Growth modeled up at this leaf: Leismer expansion ramp, +1.5 kb/d Oct 2026 rising linearly to +7.0 kb/d Sep 2027 (+0.5 kb/d per month from Jul 2026, landing on 40.0 kb/d by Dec 2027). Source: Athabasca Oil 2026 budget news release (2025-12-11), confirmed on track in the Q2 2026 press release (2026-07-29). Approved 2026-09-23.

Maintenance

No maintenance events in the current model math for this project.

Forward calendar (Oct 2026 to Sep 2027)

TimingEventImpact kb/dStandingSource
May 2027Turnaroundnot stated (null, never estimated)Pattern indicated (indicator only)None, ST53 seasonal dip analysis (repo-computed, AER ST53) (2026-09-22)
2030 (year precision)Scheduled (future window)not stated (null, never estimated)Guidance sourcedAthabasca Oil Corporation, Athabasca Oil Reports Strong 2026 First Quarter Results and Increased Cash Flow Outlook (2026-05-06)

Pattern-indicated entries are indicators only: they carry no volume and never enter model math. Math requires public-confirmed guidance.

Outlook

Named assumptions: May dip is seasonal (May flagged 4 of 9 years). Next routine turnaround on the stated 4-year frequency, around 2030. Growth modeled up at this leaf: Leismer expansion ramp, +1.5 kb/d Oct 2026 rising linearly to +7.0 kb/d Sep 2027 (+0.5 kb/d per month from Jul 2026, landing on 40.0 kb/d by Dec 2027). Source: Athabasca Oil 2026 budget news release (2025-12-11), confirmed on track in the Q2 2026 press release (2026-07-29). Approved 2026-09-23.

Confirmation status: model forecast; maintenance impacts enter the math only from public-confirmed guidance.

Market relevance

In-situ bitumen has flexible disposition (dilbit to market or upgrader feed). In the model, Leismer output is unchanged by upgrader outages and any upgrader-bound share is assumed diverted to dilbit, so its 35.6 kb/d 12-month forecast average is a steady contributor to marketable dilbit across the tradable window.

Basis: model-derived from the dashboard series above; no external view is added.

Related weekly notes

Sources

Leismer (Athabasca)
Source: AER ST53, commercial scheme mapping (repo annotations/projects.yaml)
Vintage: AER ST53 actuals through 2026-07, pulled 2026-09-22; model nowcast (_seasonal_baseline + confirmed maintenance), built 2026-09-23
Method: actuals: ST53 scheme observed, grossed up by 1.27 to ST3 in-situ level (mapped projects cover 79.0%). forecast: _seasonal_baseline (trailing-12m mean x seasonal factor from last 3 complete years).

Full citation block

Sources
PublisherDatasetURLPublishedVintage / coverageRetrieved
Alberta Energy RegulatorST3: Alberta Energy Resource Industries Monthly Statisticshttps://www.aer.ca/data-and-performance/data-and-publications/statistical-reports/st3MonthlyActuals through 2026-07 (latest file vintage 2026-08-27)2026-09-22
Alberta Energy RegulatorST53: In-situ project data (BITUMEN sheet)https://www.aer.ca/data-and-performance/data-and-publications/statistical-reports/st53MonthlyActuals through 2026-072026-09-22
Alberta Energy RegulatorST39: Mine and upgrader facility dataURL not recorded in repoMonthlyActuals through 2026-052026-09-22
Canada Energy RegulatorPipeline throughput, capacity and apportionment (open data)https://www.cer-rec.gc.ca/open/energy/throughput-capacity/Monthly, ~3-month lagJan 2018 to Jun 20262026-09-22
Company disclosuresQuarterlies, budget releases, investor presentations, earnings callsURLs per record in annotations/maintenance_forward.yamlAs publishedForward maintenance calendar window 2026-10-01 to 2027-09-30, compiled 2026-09-222026-09-22
Heavy Reading modelWCSB S&D dashboard build (21 granular leaves, grade layer, maintenance math)No public URL (repo build)Per buildForecast built 2026-09-22; Aug-Sep 2026 nowcast built 2026-09-232026-09-23

Every number on this page traces to a row above. Anything missing its own source line is flagged in place; nothing ships with an unsourced number.

Heavy Reading · the WCSB supply letter.
Public information only: AER ST3/ST39/ST53 and company disclosures via the WCSB S&D model. Nothing here is licensed data, so this page renders the same with or without ?public=1.