Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2026-09-19

The table below contains the significant transmission outages submitted as tentative to the AESO.
These Outages have not yet necessarily been approved, but are listed for awareness and coordination purposes.
An Outage has been considered significant for this table if it meets any one (1) or more of the following criteria:
  1. it affects a transmission facility operating at two hundred and forty (240) kV or greater;
  2. it affects an intertie;
  3. it affects an element connecting facilities owned by two (2) or more different legal owners of transmission facilities;
  4. it affects an element that connects a generating unit or an aggregated generating facility to the interconnected electric system;
  5. it requires the ISO to issue a dispatch or directive for generation in order to facilitate the planned outage;
  6. it affects a cutplane limit;
  7. it limits or reduces the operability of a synchronous condenser, static VAr compensator, static compensator or other similar dynamic device; or
  8. it affects high voltage direct current facilities.
Note: Where a transmission outage requires generation curtailments, the adjustments to generation will typically happen in the hours before the scheduled transmission outage and in the hour after the element is returned to service.

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Owner From To Duration Element Scheduled Activity Affected Intertie
SUNCOR 04-Jan-26 08:00 16-Oct-26 20:00 5,791 Hours
Continuous
29EDD-34 260kV Bus 29PP-45 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34), 29EDD-34 29PS-216 (29EDD-34) urgent repairs on 29PT-224 at 29EDD34 on 29PP-45 bus  
ALTALINK 14-Jul-26 08:00 22-Oct-26 17:00 1,905 Hours
Continuous
287s 552 (287s Hazelwood) 287s552 must be open during 443L and 417L outage for the 214s AIS to work properly  
ALTALINK 15-Jul-26 14:01 22-Oct-26 09:00 1,962.98 Hours
Continuous
417L (55s Olds - 281s Johnson), 55s T1 (55s Olds), 55s T2 (55s Olds), 55s 417 (55S Olds), 287s 552 (287s Hazelwood), 55s 2 (55s Olds) mobile install at 55s for P_C major upgrade, repair/replace s80, s83, s84. salvage s51.  
ALTALINK 13-Aug-26 16:31 24-Sep-26 17:00 1,008.48 Hours
Continuous
71s T1 (71s Lamoureux) bushing issue  
ALTALINK, TRANSALTA 02-Sep-26 07:00 21-Oct-26 15:00 1,184 Hours
Continuous
320p GT3 (320p Keephills) maintenance  
BCH 02-Sep-26 09:00 21-Sep-26 13:00 460 Hours
Continuous
5L96 (BCH Selkirk - BCH Vaseux Lake) maintenance, BC maintenance does not affect the Alberta ATC AB-BC
EPCOR 08-Sep-26 07:00 26-Sep-26 17:00 130 Hours
Continuous
72PM25 (Poundmaker - Meadowlark), T4 (Poundmaker), PM2402 (Poundmaker), PM2403 (Poundmaker), PM721 (Poundmaker), PMDS4 (Poundmaker), M726 (Meadowlark) doble Poundmaker TX4  
EPCOR 08-Sep-26 07:00 23-Oct-26 17:00 1,090 Hours
Continuous
805s T4 (805s Jasper), EP 805s J2405 (EP 805s Jasper), EP 805s J2406 (EP 805s Jasper), EP 805s JAB4 (EP 805s Jasper) replacement LCR Jasper J2406/JDS10  
CNRL 12-Sep-26 08:00 20-Sep-26 16:00 200 Hours
Continuous
842s 75-TR-4701 (842s Horizon Upgrading), 842s 75-1903 (842s Horizon Upgrading), 842s 75-1904 (842s Horizon Upgrading) 5YR PMs of Transformer, Breakers, Disconnects, and Protective Relays  
EPCOR 14-Sep-26 07:00 20-Sep-26 17:00 154 Hours
Continuous
EP 803s L2402 (EP 803s Lambton) Lambton: L2402 (Min Oil) breaker maintenance and CT doble  
ATCO 14-Sep-26 10:00 28-Sep-26 17:30 343.5 Hours
Continuous
840s 901T (840s McNeill Station), 840s 701T (840s McNeill Station), 840s 701 (840s McNeill Station), 840s 901 (840s McNeill Station), 840s 702C (840s McNeill Station), 840s 703C (840s McNeill Station) replace 901T bushings, upgrading and testing AB-SK
Saskpower 14-Sep-26 10:00 28-Sep-26 17:30 343.5 Hours
Continuous
Sask Power S1M Line maintenance AB-SK
ATCO 14-Sep-26 14:00 25-Sep-26 14:00 343.5 Hours
Continuous
930s Syn Condenser (930s Arcenciel), 930s 719 (930s Arcenciel), 930s 702T (930s Arcenciel) level 4 service / overhaul by ABB
- DFR replacement
 
ATCO, CNRL 15-Sep-26 08:00 19-Sep-26 16:00 104 Hours
Continuous
838s 75-SD-901 (838s Horizon Mining) relay firmware update and testing  
ATCO, CNRL 15-Sep-26 08:00 19-Sep-26 16:00 104 Hours
Continuous
838s 75-SD-901 (838s Horizon Mining), 838s 903 (838s Horizon Mining), 838s 906 (838s Horizon Mining) customer request  
ALTALINK, Lethbridge 15-Sep-26 08:00 24-Sep-26 17:00 225 Hours
Continuous
725AL (618s Riverbend - 725L tap), 725L (674s Bowron - 725AL tap), 725LE (111s Coalbanks - 725AL tap), 618s 725 (618s Riverbend), 674s 725E (674s Bowron), 111s 725LE (111s Coalbanks), 674s 12 (674s Bowron) line outage on 725LE at 674s to replace 674s12 switch and 674sPT5-CVT  
ALTALINK, Lethbridge 15-Sep-26 09:00 24-Sep-26 17:30 224.5 Hours
Continuous
618s 725 (618s Riverbend), 725AL (618s Riverbend - 725L tap), 725L (111s Coalbanks - 725AL tap), 725L (674s Bowron - 725AL tap) Outage required to replace 674s12-Disconnect Switch and 674sPT5-CVT  
CNRL 16-Sep-26 08:00 20-Sep-26 16:00 104 Hours
Continuous
842s 75-TR-7701 (842s Horizon Upgrading), 842s 75-1904 (842s Horizon Upgrading), 842s 75-1905 (842s Horizon Upgrading) maintenance  
ENMAX, ALTALINK 19-Sep-26 07:00 19-Sep-26 12:00 5 Hours
Continuous
771L (SS-47 - SS-162), 162B138-RB82 (SS-162), 47.1TR (SS-47), 47B138-771/1 (SS-47), 47B138-771 (SS-47), 47.2TR (SS-47), 162B138-RB81 (SS-162) Summer Substation Washing 162SUB, 138kV, 162MD138-771  
EPCOR 21-Sep-26 07:00 21-Sep-26 17:00 10 Hours
Continuous
EP 803s L2401 (EP 803s Lambton) Lambton: L2401, DFR Upgrade Decommissioning  
ALTALINK 21-Sep-26 07:00 28-Sep-26 18:00 179 Hours
Continuous
691L (74s Janet - 419s Chestermere) Line move for structures 4-12.  
CNRL 21-Sep-26 08:00 28-Sep-26 16:00 176 Hours
Continuous
842s 75-1901 (842s Horizon Upgrading), 842s 75-1905 (842s Horizon Upgrading), 842s 75-1906 (842s Horizon Upgrading), 842s 75-TR-5701 (842s Horizon Upgrading), 842s 75-TR-8701 (842s Horizon Upgrading) 5YR PMs of Transformer, Breakers, Disconnects, and Protective Relays  
Syncrude 21-Sep-26 08:00 01-Oct-26 16:00 248 Hours
Continuous
AL-2 (Aurora - D05 Syncrude), D05 512 (D05), D05 511 (D05), 223 (Aurora), 222 (Aurora) installing a 260kV power line as a temp bypass for future work and this outage is required to tie in the OPGW running on AL-2  
Syncrude 21-Sep-26 08:00 02-Oct-26 16:00 272 Hours
Continuous
34 (Aurora), 33B (Aurora), 34A (Aurora), 89-37 (Aurora), G21 (Aurora) Zone 3 6yr PM  
ATCO 21-Sep-26 10:00 24-Sep-26 16:00 78 Hours
Continuous
888s 906 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
ALTALINK 21-Sep-26 13:30 22-Sep-26 12:00 22.5 Hours
Continuous
251s 1352 (251s Whitla) 251s1352 HPL Major Maintenance.  
ALTALINK 21-Sep-26 14:00 24-Sep-26 17:00 75 Hours
Continuous
510s R3 (510s Sunnybrook) Reactor maintenance  
ALTALINK 21-Sep-26 15:00 24-Sep-26 17:00 74 Hours
Continuous
71s 1752 (71s Lamoureux), 71s 1652 (71s Lamoureux) 240kV switch repair 71s49, 71s50
240kV breaker maintenance 71s1652
 
ALTALINK 21-Sep-26 15:01 25-Sep-26 17:00 100 Hours
Continuous
77s T2 (77s Sagitawah) Transformer maintenance  
ALTALINK, EPCOR 22-Sep-26 07:00 22-Sep-26 17:00 10 Hours
Continuous
EP 803s L2404 (EP 803s Lambton) Lambton: L2404, DFR Upgrade Decommissioning  
EPCOR 22-Sep-26 07:00 26-Sep-26 17:00 82 Hours
Continuous
987s GT1 (987s Clover Bar), 987s SST2 (987s Clover Bar), 987s CS2 (987s Clover Bar), 987s CGB1 (987s Clover Bar), 987s CCP7214 (987s Clover Bar), 987s CC24 (987s Clover Bar), 987s CH724 (987s Clover Bar), 987s CK726 (987s Clover Bar), 987s 72kV Bus 4 (987s Clover Bar) Cloverbar: , SST2, BUS 4 Outage. CDS18 Disconnect Replacement  
ATCO, CNRL 22-Sep-26 08:00 01-Oct-26 16:00 224 Hours
Continuous
838s 75-BC-1917 (838s Horizon Mining), 838s 75-BC-1916 (838s Horizon Mining), 838s 75-TR-2801 (838s Horizon Mining) Upgrade 75-RPX-2801B From SEL 387 to SEL 487, Transformer, Breaker and Disconnect testing  
ALTALINK 22-Sep-26 11:00 23-Sep-26 13:00 26 Hours
Continuous
251s 1452 (251s Whitla) 251s1452 HPL Major Maintenance  
ATCO 23-Sep-26 08:00 25-Sep-26 18:00 34 Hours
Continuous
806s 701T (806s Oldman River) maintenance  
ALTALINK, WPLP 23-Sep-26 09:00 23-Sep-26 17:00 8 Hours
Daily
268s 268 (268s Whitecourt), 268s 503 (268s Whitecourt), 503L (268s Whitecourt - 323s Whitecourt Power) 268s268 Breaker Maint. and heater replacement  
SUNCOR 24-Sep-26 08:00 05-Oct-26 18:00 346 Hours
Continuous
29EDD-63 29PT-179 (29EDD-63 Firebag Co-Gen), 29PL7-2 (29EDD-18 Firebag - 29EDD-63), 29EDD-63 30-252-11301 (29EDD-63), 29EDD-63 91-152-500201 (29EDD-63), 29EDD-18 29-752-105 (29EDD-18 Firebag), 29EDD-18 29-752-104 (29EDD-18 Firebag) FIREBAG: Replace air bladder on 29PT-179, test 29PT-179, and execute 29PT-179 T60 replacement  
Saskpower 24-Sep-26 09:00 24-Sep-26 14:00 5 Hours
Continuous
Sask Power AS905 maintenance AB-SK
BCH, BPA 24-Sep-26 09:00 24-Sep-26 16:00 7 Hours
Continuous
5L52 (BPA Custer - BCH Ingledow) end to end trip checks AB-BC
ATCO 25-Sep-26 10:00 28-Sep-26 16:00 78 Hours
Continuous
888s 905 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
EPCOR 27-Sep-26 07:00 12-Oct-26 17:00 370 Hours
Continuous
987s GT3 (987s Clover Bar), 987s CGB3 (987s Clover Bar) CPC Request and BUS Diff Upgrade Cutovers  
ENMAX, ALTALINK 27-Sep-26 08:30 09-Oct-26 14:00 293.5 Hours
Continuous
37.2TR (SS-37), 37.82L (74s Janet - SS-37) HV SW Replacement. 37SW85, 37SW86, 37SW89  
ALTALINK 28-Sep-26 07:00 08-Oct-26 17:00 250 Hours
Continuous
510s 2652 (510s Sunnybrook), 510s 2752 (510s Sunnybrook), AML 511s 4852 (AML 511s Crossings), AML 511s 4952 (AML 511s Crossings), 1325L (510s Sunnybrook - AML 511s Crossings) Annual Valve Hall Maintenance, PRC Tx Maintenance, Doble Testing of the Transformers, PRC Relay Maintenance, Annual Yard Inspections, TDC settings changes, VCS Maintenance  
ATCO 28-Sep-26 08:00 01-Oct-26 16:00 80 Hours
Continuous
7L44 (749s Flyingshot Lake - 845s Big Mountain) Changing str 71,72,73 and 74 for high load move line raise  
SUNCOR 28-Sep-26 09:00 04-Oct-26 20:00 155 Hours
Continuous
29EDD-34 260kV Bus 29PP-45 (29EDD-34) 29EDD34 29PP45 A,C phase rebuild bus and supports that were removed as part of the 29PT-224 outage.

 
Lethbridge 28-Sep-26 09:00 15-Oct-26 17:00 416 Hours
Continuous
674s 1 (674s Bowron), 725LW (674s Bowron - 725BL tap) Line outage required on 725LW at 674s to replace 674s1-Manual Airbreak Switch and replace 674s2 and 674s6 PT's  
ALTALINK 28-Sep-26 10:00 29-Sep-26 17:30 31.5 Hours
Continuous
927L (102s Langdon - 356s Milo) URGENT 927L Str. Span 205-206. Splice conductor and install patch rod to damaged conductors, Install IP's in span 205-206  
ATCO 28-Sep-26 10:00 02-Oct-26 17:30 103.5 Hours
Continuous
2029s ACF22 (2029s Heathfield), 2029s 1223 (2029s Heathfield) PRC-005 - TRIP COIL TESTING - BREAKER 1223 @ 2029S
BREAKER SF6 3AP4FI MAINTENANCE - 1223 @ 2029S
ACF22 Breaker low SF6 (breaker 1223) @2029S Heathfield
FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF22
 
ALTALINK, TRANSALTA, Lethbridge 28-Sep-26 11:00 28-Sep-26 17:00 6 Hours
Daily
15s 725 (15s Fort Macleod), 725BL (240s McBride Lake - 725L tap), 725L (15s Fort MacLeod - 725BL tap), 725L (674s Bowron - 725BL tap) Outage required to create open point 'A' on 725L to keep 240s online  
ATCO 28-Sep-26 12:00 28-Sep-26 14:00 31 Hours
Continuous
789s 703 (789s Keg River), 7L59 (789s Keg River - 7L59 tap) PRC Trip Coil Testing  
ALTALINK 28-Sep-26 12:00 28-Sep-26 17:00 5 Hours
Continuous
63s 25 (63s Red Deer), 63s T2 (63s Red Deer) 63sT2 Monitor Warning sensor investigation.  
ALTALINK, Lethbridge 28-Sep-26 16:35 15-Oct-26 13:55 405.33 Hours
Continuous
725L (674s Bowron - 725BL tap) Lethbridge outage required to replace 674s1-Disconnect Switch, 674sPT4-CVT, 674sPTB2-3phase CVT's, new screw piles and structure for 674sPTB2-CVT's  
ALTALINK, ATCO 29-Sep-26 07:15 29-Sep-26 18:00 10.75 Hours
Daily
650s 852 (650s Hansman Lake), 650s 952 (650s Hansman Lake), 948L (650s Hansman Lake - 863s Paintearth) transmission line maintenance  
ENMAX, ALTALINK 29-Sep-26 08:00 29-Sep-26 17:30 9.5 Hours
Daily
1109L (SS-25 - SS-65) 1109L
Structure 15 Top Phase conductor Repair
 
ENMAX, ALTALINK 29-Sep-26 08:00 29-Sep-26 17:30 9.5 Hours
Continuous
1109L (SS-25 - SS-65) Altalink outage. Remove 1109L from service to repair the top phase on Structure #15  
ALTALINK 29-Sep-26 08:30 29-Sep-26 15:30 7 Hours
Daily
122s T1 (122s Alberta Newsprint) Repair leaking PRD on T1 and clean leak mitigation materials  
ATCO 29-Sep-26 10:00 01-Oct-26 14:00 31 Hours
Continuous
7L64 (779s Chinchaga River - 789s Keg River), 789s 701 (789s Keg River) PRC trip coil testing BKR 701 at Keg River  
ALTALINK, BCH 30-Sep-26 09:00 30-Sep-26 17:00 8 Hours
Continuous
887L (48s Pocaterra - 978s BCH Britt Creek) FRO Maintenance AB-BC
ALTALINK 01-Oct-26 08:00 01-Oct-26 18:00 10 Hours
Daily
1002L (163s Amoco Empress - 275s Jenner) 1002L - Replace top phase spacer on STR67
 
ALTALINK 01-Oct-26 09:00 01-Oct-26 17:30 8.5 Hours
Continuous
1043L (320p Keephills - 367s Harry Smith) 1043L111 Conductor repair  
EPCOR 05-Oct-26 07:00 18-Oct-26 17:00 322 Hours
Continuous
CV5 (EP 511s Victoria - 557s Castle Downs) CV5/TX5: Manhole Inspections and Maintenance and 72kV Breaker Fail Protection Upgrade Cutovers and Commissioning  
ENMAX, ALTALINK 05-Oct-26 08:00 05-Oct-26 16:00 8 Hours
Continuous
20.82L (SS-20 - SS-21), 21.80L (42s Sarcee - SS-21), 21.1TR (SS-21), 21.4TR (SS-21) Fall Substation Washing. Reversing Switch Check - 21.1-TC. Altalink required to remove AML VT4 60S100 fuses  
ATCO 05-Oct-26 08:00 08-Oct-26 16:00 80 Hours
Continuous
7L44 (749s Flyingshot Lake - 845s Big Mountain) Changing str 71,72,73 and 74 for high load move line raise  
ALTALINK 05-Oct-26 08:00 15-Oct-26 16:00 248 Hours
Continuous
214s 443 (214s Innisfail), 55s 443 (55S Olds), 443L (55s Olds - 214s Innisfail) Update line protections for 443L  
ALTALINK 05-Oct-26 08:30 28-Nov-26 06:30 1,295 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ATCO 05-Oct-26 09:00 07-Oct-26 17:30 56.5 Hours
Continuous
2029s 1301 (2029s Heathfield) DC HIGH SPEED SWITCH MAINTENANCE - 1301 @ 2029S
**EATL will need to run in P1 DMR Return while 1301 is out of service**

AESO PLEASE ADD SWITCHED INTO DATABASE
 
BCH, BPA 05-Oct-26 09:00 16-Oct-26 17:00 272 Hours
Continuous
5L52 (BPA Custer - BCH Ingledow) 5L52 tower replacements AB-BC
ATCO 05-Oct-26 10:00 08-Oct-26 16:00 78 Hours
Continuous
9L74 (888s Dover - 960s Birchwood Creek) 21B/9L74 relay three terminal line testing  
ATCO 05-Oct-26 12:00 09-Oct-26 12:00 96 Hours
Continuous
786s SVC (786s High Level) ET 1136310 786S High Level SVC DFR Upgrade
SVC AIR COOLED MAINTENANCE @ HIGH LEVEL 786S
 
ALTALINK, EPCOR 05-Oct-26 13:00 06-Oct-26 16:00 27 Hours
Continuous
89s 852 (89s Ellerslie), 89s 652 (89s Ellerslie), 89s 752 (89s Ellerslie), 908L (89s Ellerslie - 816s Petrolia), 908L (89s Ellerslie - 908AL tap) Breaker maintenance 89s852, Switch maintenance 89s12, 89s13  
ENMAX 06-Oct-26 08:00 06-Oct-26 12:00 4 Hours
Continuous
162B240-RB133 (SS-162) Breaker Trip Circuit Test - 162B240-RB133  
ENMAX, ALTALINK 06-Oct-26 08:00 06-Oct-26 16:00 8 Hours
Continuous
50L (44s Bearspaw Plant - SS-21), 21.1C (SS-21), 21.2TR (SS-21) Fall Substation Washing  
ENMAX, ALTALINK 06-Oct-26 08:00 06-Oct-26 17:00 9 Hours
Continuous
50L (44s Bearspaw Plant - SS-21), 44s 50X (44s Bearspaw Plant) fall substation washing  
SUNCOR 06-Oct-26 08:00 12-Oct-26 20:00 252 Hours
Continuous
29EDD-2 29PT-3 (29EDD-2 Tar Island), 29PL6-22 (29EDD-1 Millennium - 29EDD-2 Tar Island) 29EDD2;29PT-3, 29PL6-22 SYSTEM;PM 5y,10y
 
SUNCOR 06-Oct-26 08:00 12-Oct-26 20:00 156 Hours
Continuous
29EDD-2 29PT-3 (29EDD-2 Tar Island), 29PL6-22 (29EDD-1 Millennium - 29EDD-2 Tar Island) 29EDD2; 29PP-2; 39PT-401 & 30PP-52 SYSTEM;PM 5y - 450504726; 29PT-3 Bushing Replacement; 29EDD2;39PT-401 & 30PP-52 SYSTEM;PM 5y
 
ENMAX 06-Oct-26 12:00 06-Oct-26 16:00 4 Hours
Continuous
162B240-RB134 (SS-162) Breaker Trip Circuit Test - 162B240-RB134  
ALTALINK 06-Oct-26 16:00 08-Oct-26 17:00 49 Hours
Continuous
89s 852 (89s Ellerslie), 89s 752 (89s Ellerslie), 908L (89s Ellerslie - 908AL tap) Breaker maintenance 89s852, Switch maintenance 89s14, 89s15  
ENMAX 07-Oct-26 08:00 07-Oct-26 12:00 4 Hours
Continuous
162B240-RB135 (SS-162) Breaker Trip Circuit Test - 162B240-RB135  
ATCO, ALTALINK 07-Oct-26 08:00 07-Oct-26 17:00 9 Hours
Continuous
760L (760AL tap - 7LA760 tap) install interphase spacers  
ALTALINK 07-Oct-26 08:00 07-Oct-26 17:00 9 Hours
Daily
801L (62s Brazeau Plant - 294s Brazeau Plant Outlet Works) 801L replace glass on STR 65 and 72  
Syncrude 07-Oct-26 08:00 28-Oct-26 16:00 512 Hours
Continuous
1335 (Syncrude Mildred Lake), 134 (Syncrude Mildred Lake), 135 (Syncrude Mildred Lake), Mildred T1 (Syncrude Mildred Lake), Mildred T2 (Syncrude Mildred Lake), 2235 (Syncrude Mildred Lake), 234 (Syncrude Mildred Lake), 235 (Syncrude Mildred Lake), 3235 (Syncrude Mildred Lake), 335 (Syncrude Mildred Lake), 334 (Syncrude Mildred Lake), Mildred T3 (Syncrude Mildred Lake), Mildred T16 (Syncrude Mildred Lake), 1635 (Syncrude Mildred Lake), 1634 (Syncrude Mildred Lake), 1434 (Syncrude Mildred Lake), 1435 (Syncrude Mildred Lake), Mildred T14 (Syncrude Mildred Lake), Mildred T19 (Syncrude Mildred Lake), 1935 (Syncrude Mildred Lake), 1934 (Syncrude Mildred Lake), 814 (Syncrude Mildred Lake), 815 (Syncrude Mildred Lake), 816 (Syncrude Mildred Lake), Mildred Lake 72kV Bus B (Sycrude Mildred Lake), ML1 (D05 - Syncrude Mildred Lake), 914 (Syncrude Mildred Lake), 915 (Syncrude Mildred Lake), 916 (Syncrude Mildred Lake), 1224A (Syncrude Mildred Lake), 1224B (Syncrude Mildred Lake), 1225 (Syncrude Mildred Lake), D05 76 (D05), D05 76A (D05), D05 76B (D05) SCL - Perform 72kV "B" Bus PM in Plant 31 at Mildred Lake.

 
ENMAX 07-Oct-26 12:00 07-Oct-26 16:00 4 Hours
Continuous
162B240-RB136 (SS-162) Breaker Trip Circuit Test - 162B240-RB136  
ALTALINK 08-Oct-26 07:00 08-Oct-26 18:00 11 Hours
Continuous
61s 202X (61s Lodgepole), 62s 202 (62s Brazeau Plant), 202L (61s Lodgepole - 62s Brazeau Plant) Line Maintenance and High Load move  
ENMAX 08-Oct-26 08:00 08-Oct-26 12:00 4 Hours
Continuous
162B240-RB131 (SS-162) Breaker Trip Circuit Test - 162B240-RB131  
ENMAX 08-Oct-26 12:00 08-Oct-26 16:00 4 Hours
Continuous
162B240-RB132 (SS-162) Breaker Trip Circuit Test - 162B240-RB132  
ATCO 12-Oct-26 10:00 15-Oct-26 16:00 78 Hours
Continuous
888s 906 (888s Dover) 21A/9L74 relay replacement. Cutover breaker and CT to new protection  
ATCO 12-Oct-26 10:00 16-Oct-26 16:00 102 Hours
Continuous
951s SVC (951s Thickwood) Annual maintenance/inspection, config changes.919A B Phase requires adjustment.  
ATCO, ALTALINK 13-Oct-26 07:00 17-Oct-26 17:00 106 Hours
Continuous
962L (87s Gaetz - 972s Tinchebray) 962L Interphase spacer work From Span 1 through 243 Using HEC with a Helicopter  
ATCO, ALTALINK 13-Oct-26 07:00 17-Oct-26 17:00 106 Hours
Continuous
986L (87s Gaetz - 972s Tinchebray) 986L Interphase spacer work From Span 1 through 243 using HEC with a Helicopter  
ATCO, ALTALINK 13-Oct-26 07:00 17-Oct-26 17:00 106 Hours
Continuous
9L62 (87s Gaetz - 972s Tinchebray) AltaLink Request: Interphase spacer work From Span 1 through 243 using HEC with a Helicopter.
ATCO needs to enable the following RAS logics
RAS 134 Logic 1b, RAS 134 Logic 2, RAS 211, RAS 215 , 973S RAS 134 , 615S RAS 134, 1045S RAS 134
 
ATCO, ALTALINK 13-Oct-26 07:00 17-Oct-26 17:00 106 Hours
Continuous
9L86 (87s Gaetz - 972s Tinchebray) AltaLink Request: Interphase spacer work From Span 1 through 243 using HEC with a Helicopter.
ATCO needs to enable the following RAS logics
RAS 134 Logic 1b, RAS 134 Logic 2, RAS 211, RAS 215 , 973S RAS 134 , 615S RAS 134, 1045S RAS 134
 
BCH, BPA 13-Oct-26 09:00 16-Oct-26 17:00 80 Hours
Continuous
5L52 (BPA Custer - BCH Ingledow) glass replacement AB-BC
ALTALINK 13-Oct-26 12:30 15-Oct-26 17:00 52.5 Hours
Continuous
89s 952 (89s Ellerslie), 89s 652 (89s Ellerslie), 89s 1352 (89s Ellerslie), 89s 252 (89s Ellerslie), 89s 1789 (89s Ellerslie), 89s T1 (89s Ellerslie), 89s Ellerslie 240kV Bus 1 89s1352 Low gas top up

Switch repairs/hot spots on;
-89s25 (Will not open to 90deg)
-89s17
-89s9
-89s1
 
ALTALINK 14-Oct-26 07:30 15-Oct-26 17:00 33.5 Hours
Continuous
74s 77 (74s Janet), 74s T2 (74s Janet) 74sT2 LO_SLOWGAS_PRD_MT Issue  
ATCO, AIRLIQUIDE 14-Oct-26 12:15 15-Oct-26 16:00 28 Hours
Continuous
ALC03L (402s Scotford Expansion One - 408s Air Liquide Scotford) Insulator cleaning and deficiency repair on ALC03L. Avian mitigation bird perch deterrents  
ALTALINK 15-Oct-26 08:00 15-Oct-26 18:00 10 Hours
Continuous
158s 763N (158s Vauxhall), 28s 47 (28s West Brooks), 28s 31 (28s West Brooks), 447s 763A (447s Enchant), 447s 16 (447s Enchant), 763AL (447s Enchant - 763A1L tap), 763L (158s Vauxhall - 763AL tap), 763L (28s West Brooks - 763AL tap) 447s27 Replace line VT. (Like for like replacement)  
ALTALINK, TRANSALTA, Lethbridge 15-Oct-26 17:10 15-Oct-26 21:00 3.83 Hours
Continuous
15s 725 (15s Fort Macleod), 725BL (240s McBride Lake - 725L tap), 725L (15s Fort MacLeod - 725BL tap), 725L (674s Bowron - 725BL tap) to close 725L Open Point 'A' and restore 725L to normal  
ATCO 16-Oct-26 10:00 19-Oct-26 16:00 78 Hours
Continuous
888s 905 (888s Dover) 21A/9L74 relay replacement. Cutover breaker and CT to new protection  
EPCOR 19-Oct-26 07:00 11-Dec-26 17:00 1,283 Hours
Continuous
814s T2 (814s Bellamy), BR722 (Rossdale), 814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy), T1 (Rossdale), R721 (Rossdale), RR723 (Rossdale) Bellamy: TX2 Emergency Bushing Replacement and Rossdale TX1 Installation  
ALTALINK 19-Oct-26 07:30 23-Oct-26 17:00 105.5 Hours
Continuous
AML 511s 1152 (AML 511s Crossings), AML 511s T30 (AML 511s Crossings) Annual standard maintenance  
ALTALINK 19-Oct-26 09:00 23-Oct-26 17:30 104.5 Hours
Continuous
288s 152 (288s Wolf Creek), 288s 352 (288s Wolf Creek), 1083L (63s Red Deer - 288s Wolf Creek) 1083L Line maintenance, 288s1083 switch repair  
BCH, BPA 19-Oct-26 09:00 30-Oct-26 17:00 272 Hours
Continuous
5L51 (BPA Custer - BCH Ingledow) tower replacement AB-BC
ALTALINK 19-Oct-26 11:00 23-Oct-26 11:00 96 Hours
Continuous
163s 1552 (163s Amoco Empress) 1552 Breaker failure and control protection upgrade  
ALTALINK, ICPCL 19-Oct-26 11:00 23-Oct-26 17:30 102.5 Hours
Continuous
225AL (313s Raymond Reservoir - 225L tap), 225L (225s Magrath - 225AL tap), 225L (67s Stirling - 225AL tap) Line maintenance
 
ATCO, GREENGATEP 20-Oct-26 09:00 03-Nov-26 17:30 345.5 Hours
Continuous
801s 902 (801s Anderson), 801s 903 (801s Anderson), 9L59 (801s Anderson - 9LA59 tap), 9L59 (972s Tinchebray - 9LA59 tap) Replacement of failed 9L59D1 at 801s Anderson  
BCH 21-Oct-26 08:00 23-Oct-26 16:00 56 Hours
Continuous
T3 (BCH Natal) inspection/doble AB-BC
ALTALINK 22-Oct-26 08:00 29-Oct-26 09:00 169 Hours
Continuous
214s 443 (214s Innisfail), 55s 443 (55S Olds), 55s T2 (55s Olds), 443L (55s Olds - 214s Innisfail) Remove mobile.  
ALTALINK 22-Oct-26 13:00 31-Dec-27 17:00 10,445 Hours
Continuous
359s T2 (359s Esso West Pembina) Replace T2 HV bushings. Replace T2 H0 & X0 bushings. T2 maintenance, oil leak repair, LTC filter install. T2 metering replacement.  
Syncrude 23-Oct-26 08:00 06-Nov-26 16:00 345 Hours
Continuous
11A (Aurora), 21A (Aurora), 31A (Aurora), 89-210 (Aurora), 89-51 (Aurora), T1 (Aurora), 211A (Aurora), 221A (Aurora), 260kV Bus 1 (Aurora), 72 kV Bus 1 (Aurora) 6yr PM  
ALTALINK 23-Oct-26 09:00 23-Oct-26 13:00 4 Hours
Continuous
163s 1752 (163s Amoco Empress) 11/1552 breaker fail trip testing  
ALTALINK, BCH 24-Oct-26 05:00 24-Oct-26 08:00 3 Hours
Continuous
1L274 (BCH Natal - BCH Line Creek tap), 1L274 (BCH Elkford tap - BCH Line Creek tap) test energize new equipment AB-BC
ALTALINK, EPCOR 24-Oct-26 07:00 25-Oct-26 17:00 34 Hours
Continuous
1044L (EP 805s Jasper - 816s Petrolia), 816s P2405 (816s Petrolia), 816s P2406 (816s Petrolia) Petrolia/1044L: CT Wiring Changes  
ALTALINK, EPCOR 26-Oct-26 07:00 30-Oct-26 17:00 106 Hours
Continuous
909L (89s Ellerslie - 665s Dome), 665s D2401 (665s Dome), 665s D2404 (665s Dome), 72DS26 (665s Dome - Strathcona) 909LE/Dome: Dome CVT LCR and 909LE Metering Upgrade  
EPCOR 26-Oct-26 07:00 30-Oct-26 17:00 106 Hours
Continuous
EP 803s T2 (EP 803s Lambton), EP 803s L2402 (EP 803s Lambton), EP 803s L2405 (EP 803s Lambton) Lambton: TX2 Zone, DFR Cutovers and Commissioning  
EPCOR 26-Oct-26 07:00 18-Dec-26 17:00 1,283 Hours
Continuous
805s T3 (805s Jasper), EP 805s J2404 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: J2404/JAB3/JDS9 Replacement LCR  
ENMAX, ALTALINK 26-Oct-26 08:00 04-Nov-26 16:00 225 Hours
Continuous
24.83L (74s Janet - SS-24) Steel pole installation  
ENMAX, ALTALINK 26-Oct-26 08:00 04-Nov-26 16:00 225 Hours
Continuous
24.83L (74s Janet - SS-24), 74s 24.83X (74s Janet) Enmax Steel pole installation  
ATCO 26-Oct-26 08:00 13-Nov-26 17:00 442 Hours
Continuous
806s 701T (806s Oldman River) Telecommunications Upgrade, new UPS upgrades.  
ATCO 26-Oct-26 09:00 26-Oct-26 17:30 32 Hours
Continuous
757s 704 (757s Battle River) BREAKER SF6 LTB145D1/B TESTING - 704 @ 757S
PRC-005 - TRIP COIL TESTING - BREAKER 704 @ 757S
 
ALTALINK 26-Oct-26 09:00 28-Oct-26 17:30 56.5 Hours
Continuous
924L (102s Langdon - 356s Milo) 924L192 Urgent repair Interphase spacer replacement  
ALTALINK, EPCOR 26-Oct-26 09:00 30-Oct-26 17:30 104.5 Hours
Continuous
89s 1052 (89s Ellerslie), 89s 1152 (89s Ellerslie), 909L (89s Ellerslie - 665s Dome) 909LE/Dome: Dome CVT LCR and 909LE Metering Upgrade  
ATCO 26-Oct-26 10:00 29-Oct-26 16:00 78 Hours
Continuous
9L74 (888s Dover - 960s Birchwood Creek), 888s 905 (888s Dover), 888s 906 (888s Dover), 960s 901 (960s Birchwood Creek), 960s 902 (960s Birchwood Creek) 21A/9L74 relay three terminal line testing  
ATCO, ALTALINK 26-Oct-26 10:00 02-Nov-26 16:00 175 Hours
Continuous
7L230 (69s North Barrhead - 888AL tap), 7L230 (743s Sarah Lake - 888AL tap) Replace 7L230D1 disconnect switch  
ALTALINK 26-Oct-26 11:00 30-Oct-26 11:00 96 Hours
Continuous
163s 1252 (163s Amoco Empress) 1252 Breaker failure & control protection upgrade  
ALTALINK 26-Oct-26 12:00 30-Oct-26 13:00 97 Hours
Continuous
602s T1 (602s Cold Creek) Replace 25kv MOD switch 602s10  
ALTALINK 27-Oct-26 07:00 27-Oct-26 17:00 10 Hours
Continuous
AML 511s 5252 (AML 511s Crossings) PRC Relay Maintenance on 5252 Siemens 6MD  
ALTALINK 27-Oct-26 08:30 30-Oct-26 16:30 80 Hours
Continuous
836L (61s Lodgepole - 283s Violet Grove), 61s 836N (61s Lodgepole) CT Replacement of CTs associated with 61s836N Breaker (CTL8)  
ALTALINK 28-Oct-26 07:00 28-Oct-26 15:00 8 Hours
Continuous
163s T1 (163s Amoco Empress) Breaker Fail upgrade project: 11/1252 & 11/1552 breaker fail trip testing. Trip testing of 163s501, 163sXA, 163sXB  
ALTALINK 28-Oct-26 07:00 28-Oct-26 15:00 8 Hours
Continuous
AML 511s 5352 (AML 511s Crossings) PRC Relay Maintenance on 5352 Siemens 6MD  
EPCOR 28-Oct-26 07:00 28-Oct-26 17:00 10 Hours
Continuous
557s CD2401 (557s Castle Downs) Castledowns: CD2401 NAIT Student Substation Tour  
ALTALINK 28-Oct-26 10:00 28-Oct-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 29-Oct-26 07:00 29-Oct-26 17:00 10 Hours
Continuous
AML 511s 5052 (AML 511s Crossings) PRC Mnt 0511DC ACF1 (s5052) 6MD66 CI  
ALTALINK 29-Oct-26 08:00 31-Oct-26 18:00 58 Hours
Continuous
927L (102s Langdon - 356s Milo) 927L - (Urgent repair) Replace 2 Interphase spacers in span 188  
ALTALINK 29-Oct-26 10:00 29-Oct-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ALTALINK 30-Oct-26 09:00 30-Oct-26 13:00 4 Hours
Continuous
163s 1552 (163s Amoco Empress) 11/1252 Breaker Fail trip testing  
ALTALINK 30-Oct-26 11:00 30-Oct-26 14:00 3 Hours
Continuous
163s 1352 (163s Amoco Empress) 11/1252 breaker fail trip testing  
ALTALINK, EPCOR 02-Nov-26 07:00 13-Nov-26 17:00 274 Hours
Continuous
909L (310p Sundance - 665s Dome), 665s D2403 (665s Dome) Dome: 909LW/D2403, Metering Upgrade Cutovers and Commissioning  
BCH, BPA 02-Nov-26 08:00 06-Nov-26 18:30 106.5 Hours
Continuous
5L51 (BPA Custer - BCH Ingledow) tower replacement AB-BC
BCH 02-Nov-26 08:00 15-Nov-26 12:00 316 Hours
Continuous
5L98 (BCH Nicola - BCH Vaseux Lake) replacement of equipment AB-BC
ALTALINK 03-Nov-26 07:00 03-Nov-26 17:00 10 Hours
Continuous
510s 2552 (510s Sunnybrook) PRC Relay Mnt 0510DC ACF1 (s2552) 6MD66 CI  
ALTALINK 03-Nov-26 08:00 04-Nov-26 17:30 33.5 Hours
Continuous
1037L (138s Windy Flats - 266s SC1), 1037L (237s Foothills - 266s SC1) 1037L Install Vibration monitors and weather stations at Structure 285 and 334.  
ATCO 03-Nov-26 09:00 03-Nov-26 14:00 5 Hours
Continuous
888s 902 (888s Dover) New 21B/9L74 relay has 50BF/906 function internally. Must trip adjacent breakers to 906.  
ALTALINK 03-Nov-26 09:00 07-Nov-26 17:00 104 Hours
Continuous
71s T2 (71s Lamoureux), 71s 240kV East Bus (71s Lamoureux), 71s 1752 (71s Lamoureux), 71s 1452 (71s Lamoureux), 71s 1352 (71s Lamoureux), 71s 32 (71s Lamoureux) multiple switch repair/replacement and maintenance 71s36, 71s37, 71s46, 71s47  
ALTALINK 04-Nov-26 07:00 04-Nov-26 17:00 10 Hours
Continuous
510s 1952 (510s Sunnybrook) PRC Relay Mnt 0510DC ACF1 (s1952) 6MD66 CI  
ATCO 04-Nov-26 09:00 04-Nov-26 14:00 5 Hours
Continuous
888s 909 (888s Dover) New 21B/9L74 relay has 50BF/906 function internally. Must trip adjacent breakers to 906. 21A/9L74 will still be protecting 9L74. 21B/9L74 will be blocked as to not affect other in service protection.  
ATCO 04-Nov-26 10:00 09-Nov-26 19:00 129 Hours
Continuous
9L20 (755s Cordel - 766s Nevis) Installing spacer dampers on Line with heli supported methods.  
ALTALINK 05-Nov-26 03:30 05-Nov-26 06:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 05-Nov-26 07:00 05-Nov-26 17:00 10 Hours
Continuous
510s 2052 (510s Sunnybrook) PRC Relay Mnt 0510DC ACF2 (s2052) 6MD66 CI  
ATCO 05-Nov-26 09:00 05-Nov-26 14:00 5 Hours
Continuous
888s 912 (888s Dover) New 21B/9L74 relay has 50BF/906 function internally. Must trip adjacent breakers to 906. 21A/9L74 will still be protecting 9L74. 21B/9L74 will be blocked as to not affect other in service protection.  
Syncrude 07-Nov-26 08:00 17-Nov-26 16:00 248 Hours
Continuous
223 (Aurora), 222B (Aurora), 89-225 (Aurora), 223A (Aurora) Zone 4 6yr PM  
EPCOR 09-Nov-26 07:00 11-Dec-26 17:00 778 Hours
Continuous
PM2405 (Poundmaker) Poundmaker: P2405 Breaker Replacement  
ALTALINK 09-Nov-26 12:00 10-Nov-26 16:00 28 Hours
Continuous
359s T2 (359s Esso West Pembina) T2 meter replacement.  
SUNCOR 10-Nov-26 10:00 15-Nov-26 18:00 128 Hours
Continuous
29PL9-12 (29EDD-34 - 29EDD-65) Firebag: Cleaning up contamination from Pad 112 blow out 300772223  
EPCOR 16-Nov-26 07:00 20-Nov-26 17:00 106 Hours
Continuous
EP 803s T1 (EP 803s Lambton), EP 803s L2401 (EP 803s Lambton), EP 803s L2402 (EP 803s Lambton) Lambton: TX1 Zone, DFR Cutovers and Commissioning  
ALTALINK, EPCOR 16-Nov-26 08:30 27-Nov-26 18:00 273.5 Hours
Continuous
908L (89s Ellerslie - 816s Petrolia) Petrolia: 908LE Surge Arrestor and CVT LCR  
ALTALINK 16-Nov-26 09:00 17-Nov-26 17:00 32 Hours
Continuous
71s 452 (71s Lamoureux), 71s 352 (71s Lamoureux), 71s 787X (71s Lamoureux), 787L (71s Lamoureux - 787AL tap) 71s787X switch adjustment, transmission line maintenance  
ALTALINK, EPCOR 16-Nov-26 09:30 27-Nov-26 17:00 271.5 Hours
Continuous
908L (89s Ellerslie - 816s Petrolia), 816s P2401 (816s Petrolia), 816s P2406 (816s Petrolia) Petrolia: 908LE Surge Arrestor and CVT LCR  
ATCO 16-Nov-26 10:00 19-Nov-26 14:00 76 Hours
Continuous
827s SVC (827s Cranberry Lake) ET 1136489 827S Cranberry Lake SVC DFR Upgrade
SVC AIR COOLED MAINTENANCE @ CRANBERRY SVC 827S
 
SUNCOR 16-Nov-26 10:00 20-Nov-26 18:00 104 Hours
Continuous
29PL9-13 (29EDD-34 - 29EDD-65) Firebag: Replace components - 29PL9-13 Contamination clean up from Pad 112 blowout 300772224  
ATCO, ALTALINK 16-Nov-26 11:00 18-Nov-26 13:00 50 Hours
Continuous
962L (87s Gaetz - 972s Tinchebray) Replace motor on 9L62D1  
ALTALINK 16-Nov-26 11:30 20-Nov-26 17:00 101.5 Hours
Continuous
71s 1452 (71s Lamoureux), 71s 1352 (71s Lamoureux), 71s 997E (71s Lamoureux) Switch replacement 71s997E, switch repair 71s46.
 
ATCO 16-Nov-26 12:00 18-Nov-26 11:59 47.98 Hours
Continuous
972s 905 (972s Tinchebray) Replace motor on 9L62D1.  
ATCO 16-Nov-26 12:00 19-Nov-26 12:00 72 Hours
Continuous
740s 705 (740s H.R. Milner), 7L80 (740s H.R. Milner - 857s Kakwa Ridge) PRC-005 - MICROPROCESSOR RELAY TESTING
TCM Program. RTXP Test Switch Mitigation and Replacement
Both RAS-A and RAS-B 7L80 will also need be OOS for the RTXP work on 21A and 21B 7L80
 
ATCO, GREENGATEP 18-Nov-26 12:00 20-Nov-26 12:00 48 Hours
Continuous
9L16 (755s Cordel - 972s Tinchebray), 972s 908 (972s Tinchebray), 972s 909 (972s Tinchebray) Replace motor on 9L16D2.  
ALTALINK, EPCOR 23-Nov-26 07:00 27-Nov-26 17:00 106 Hours
Continuous
1058L (657s Summerside - EP 803s Lambton), EP 803s L2403 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton) 1058L: Lambton, DFR Cutovers and Commissioning  
ATCO 23-Nov-26 10:00 23-Nov-26 17:00 7 Hours
Continuous
959s 904 (959s Lanfine) Cutover and Commission Bkr 904 status to RAS 204 A/B  
ATCO 23-Nov-26 10:00 24-Nov-26 15:00 29 Hours
Continuous
813s 901 (813s Little Smoky) 813S Little Smoky - 901 S/C Open/Close Control Mapping Issue  
ALTALINK 23-Nov-26 12:30 26-Nov-26 17:00 76.5 Hours
Continuous
71s 452 (71s Lamoureux), 71s 852 (71s Lamoureux), 71s 708N (71s Lamoureux), 71s 31 (71s Lamoureux), 71s T2 (71s Lamoureux), 71s 138kV East Bus (71s Lamoureux) 138kV switch repairs 71s8, 71s42, 71s708N  
ATCO 23-Nov-26 13:00 30-Nov-26 13:00 168 Hours
Continuous
930s SVC (930s Arcenciel) ET 1137010 930S Arcenciel SVC DFR Upgrade
ET 1137018 930S Arcenciel SVC Protection Upgrade
SVC AIR COOLED MAINTENANCE @ ARCENCIEL 930S
 
ALTALINK 24-Nov-26 08:00 25-Nov-26 11:30 27.5 Hours
Continuous
650s 252 (650s Hansman Lake) adding a maintenance switch to 650s252  
ATCO 24-Nov-26 10:00 24-Nov-26 17:00 7 Hours
Continuous
959s 919 (959s Lanfine) Cutover and Commission Bkr 919 status to RAS 204 A/B  
ATCO 25-Nov-26 10:00 25-Nov-26 17:00 7 Hours
Continuous
959s 920 (959s Lanfine) Cutover and Commission Bkr 920 status to RAS 204 A/B  
ALTALINK 25-Nov-26 12:30 26-Nov-26 14:00 25.5 Hours
Continuous
650s 352 (650s Hansman Lake) adding a maintenance switch to 650s352  
Syncrude 28-Nov-26 08:00 02-Dec-26 16:00 104 Hours
Continuous
D05 511 (D05), D05 511B (D05), D05 512 (D05), D05 512A (D05), D05 514 (D05), 223A (Aurora), 223 (Aurora), 222B (Aurora), 222 (Aurora), 89-225 (Aurora), AL-2 (Aurora - D05 Syncrude) Completing 260kV Tie ins with our Projects team to reroute the Power line.  
EPCOR, ALTALINK 30-Nov-26 07:00 04-Dec-26 17:00 106 Hours
Continuous
EP 803s T3 (EP 803s Lambton), EP 803s L2403 (EP 803s Lambton), EP 803s L2405 (EP 803s Lambton), EP 803s L721 (EP 803s Lambton), 72LH8 (EP 803s Lambton - EP Hardisty), 72LS24 (EP 803s Lambton - Strathcona) Lambton: TX3 Zone, DFR Cutovers and Commissioning  
ATCO 30-Nov-26 12:00 03-Dec-26 12:00 72 Hours
Continuous
813s SVC (813s Little Smoky) 813S Little Smoky SVC DFR Upgrade  
EPCOR 04-Dec-26 07:00 04-Dec-26 17:00 10 Hours
Continuous
557s T1 (557s Castle Downs), 557s CD2401 (557s Castle Downs), 557s CD2406 (557s Castle Downs) Castledowns: TX1 Zone, Wiring Changes and Op Checks  
Syncrude 05-Dec-26 08:00 09-Dec-26 16:00 104 Hours
Continuous
D05 517 (D05), D05 519 (D05), D05 517B (D05), D05 519A (D05), D05 520 (D05), 213 (Aurora), 213A (Aurora), 211 (Aurora), 211B (Aurora), 89-215 (Aurora), AL-1 (Aurora - D05) Isolate AL-1 to allow Projects to complete 260kV Tie ins for Powerline Bypass  
ALTALINK, EPCOR 07-Dec-26 07:00 11-Dec-26 17:00 106 Hours
Continuous
1059AL (52s East Industrial - 1059L tap), 1059L (EP 803s Lambton - 1059AL tap), EP 803s L2401 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton) 1059L: Lambton, DFR Cutovers and Commissioning  
ALTALINK 07-Dec-26 10:00 11-Dec-26 17:30 103.5 Hours
Continuous
514L (396s Pincher Creek - 514BL tap) 514L
Structure 48 - Replace cross arm
Structure 99 - Replace structure
Structure 102 - Replace structure
Structure 158 - Replace Cross Arm
 
ALTALINK 14-Dec-26 08:00 15-Dec-26 17:30 33.5 Hours
Continuous
1325L (510s Sunnybrook - AML 511s Crossings) 1325L Add Bird Diverter str. protection. 1325L501- monopole catwalk install and 1325L542- Lattice  
ALTALINK, EPCOR 14-Dec-26 09:30 17-Dec-26 17:00 79.5 Hours
Continuous
920L (37s North Calder - 557s Castle Downs), 557s CD2401 (557s Castle Downs), 557s CD2403 (557s Castle Downs) 920LW/Castledowns: Surge Arrestor LCR  
ALTALINK 16-Dec-26 10:00 16-Dec-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 17-Dec-26 08:00 17-Dec-26 17:30 9.5 Hours
Continuous
936L (5s East Calgary - 102s Langdon) 936L str.67 - re-install damper on center phase  
ALTALINK 17-Dec-26 10:00 17-Dec-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ALTALINK 23-Dec-26 23:30 24-Dec-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 24-Dec-26 03:30 24-Dec-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
EPCOR 04-Jan-27 07:00 12-Feb-27 17:00 946 Hours
Continuous
EP 805s J2405 (EP 805s Jasper) Jasper: J2405 Replacement LCR  
ALTALINK 11-Jan-27 10:00 21-Jan-27 17:30 247.5 Hours
Continuous
170L (632s Russell - 799s Coleman) 170L
Replace Structure 35
Replace Structure 36
Replace Structure 40
Replace Structure 41
 
EPCOR 22-Jan-27 07:00 25-Jan-27 17:00 82 Hours
Continuous
1055L (629s Argyll Transfer Station - 816s Petrolia), 240BA3 (629s Argyll Transfer Station - 814s Bellamy) 1055L/240BA3: ADS3 LCR Preparation Outage, jumpering out ADS2  
ALTALINK 25-Jan-27 10:00 04-Feb-27 17:30 247.5 Hours
Continuous
799s 170E (799s Coleman), 170L (632s Russell - 799s Coleman) 170L
Replace Structures 57, 59, 60, 62, 63, 64, 65, 89, 90, 91, 92, 93, 94, 95, 96
 
ALTALINK, EPCOR 25-Jan-27 16:00 01-Feb-27 18:00 170 Hours
Continuous
1056L (89s Ellerslie - 629s Argyll Transfer Station) 1056L/240BA2: ADS3 LCR (1055L and BA3 will be jumpered out and energized bypassing ADS2 for the duration of this outage)  
EPCOR, ALTALINK 25-Jan-27 17:00 01-Feb-27 17:00 168 Hours
Continuous
240BA2 (629s Argyll Transfer Station - 814s Bellamy), 1056L (89s Ellerslie - 629s Argyll Transfer Station) 1056L/240BA2: ADS3 LCR (1055L and BA3 will be jumpered out and energized bypassing ADS2 for the duration of this outage)  
EPCOR 01-Feb-27 17:00 05-Feb-27 17:00 96 Hours
Continuous
1055L (629s Argyll Transfer Station - 816s Petrolia), 240BA3 (629s Argyll Transfer Station - 814s Bellamy) 1055L/240BA3: ADS3 LCR Removing ADS2 jumper, restoring configuration  
ALTALINK 08-Feb-27 10:00 11-Feb-27 17:30 79.5 Hours
Continuous
170L (632s Russell - 799s Coleman) 170L
Replace Structures 66, 67, 82, 83
 
EPCOR 16-Feb-27 07:00 30-Mar-27 17:00 1,017 Hours
Continuous
EP 805s J2407 (EP 805s Jasper) Jasper: J2407 Replacement LCR  
ALTALINK 16-Feb-27 10:00 26-Feb-27 17:30 247.5 Hours
Continuous
170L (632s Russell - 799s Coleman) 170L
Replace Structures 102 & 103
 
ALTALINK, EPCOR 19-Feb-27 07:00 05-Mar-27 17:00 346 Hours
Continuous
1045L (EP 805s Jasper - 1045AL tap), EP 805s J2406 (EP 805s Jasper), EP 805s J2407 (EP 805s Jasper) 1045L/Jasper: J2407 Replacement LCR  
ALTALINK 19-Feb-27 07:00 05-Mar-27 18:00 347 Hours
Continuous
1045AL (320p Keephills - 1045L tap), 1045L (310p Sundance - 1045AL tap) 1045L/Jasper: J2407 Replacement LCR  
EPCOR 22-Feb-27 07:00 05-Mar-27 17:00 274 Hours
Continuous
814s T1 (814s Bellamy), BR721 (Rossdale), 814s B2401 (814s Bellamy), 814s B2407 (814s Bellamy) Bellamy: TX1 Temp Monitor Install  
ALTALINK 03-Mar-27 08:00 04-Mar-27 17:30 33.5 Hours
Continuous
172L (254s Coaldale - 172EL tap) 172L str.953,1000,1002,1004 Bonding and grounding repairs, str.1004 arm change
 
ALTALINK 05-Mar-27 08:00 05-Mar-27 17:30 9.5 Hours
Continuous
172L (83s Taber - 172EL tap) 172L str. 938 - Arm change  
EPCOR 08-Mar-27 07:00 19-Mar-27 17:00 273 Hours
Continuous
814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy), 814s T2 (814s Bellamy), BR722 (Rossdale) Bellamy: TX2 LTC Monitor Install  
ATCO 08-Mar-27 10:00 17-Mar-27 17:00 222 Hours
Continuous
9L24 (946s Oakland - 959s Lanfine), 959s 906 (959s Lanfine), 959s 905 (959s Lanfine), 946s 902 (946s Oakland), 946s 903 (946s Oakland) Replace A/B protection relays at 959S Lanfine and 946S Oakland
Cut in and reroute 9L24
Connect new 9LA24 T-tap
Commission Telecom and Protection to new 1072S Rose Lynn substation
 
EPCOR 05-Apr-27 07:00 07-May-27 17:00 778 Hours
Continuous
52s T2 (52s East Industrial), 52s E2402 (52s East Industrial) East Industrial: TX2 Bushing Replacement  
SUNCOR 05-Apr-27 09:00 11-Apr-27 20:00 155 Hours
Continuous
29PL9-12 (29EDD-34 - 29EDD-65) 29EDD34;29PL9-12 SYSTEM;PM 5y,10y
 
SUNCOR 06-Apr-27 09:00 16-Apr-27 20:00 251 Hours
Continuous
29EDD-34 29PT-112 (29EDD-34), 29EDD-34 29-752-121 (29EDD-34), 29EDD-34 29PS-68 (29EDD-34), 29EDD-34 29PS-67 (29EDD-34), 29EDD-34 29PS-66 (29EDD-34), 29EDD-34 29PS-65 (29EDD-34), 29EDD-34 29PS-225 (29EDD-34), 29EDD-34 29PS-230 (29EDD-34), 29EDD-34 29-952-141 (29EDD-34), 29EDD-34 29-952-131 (29EDD-34), 29EDD-34 29-952-111 (29EDD-34) 29EDD34;29PT-112 & 29PP-24 SYSTEM;PM
This will Place 29EDD-34 on one 260 kV bus and drop 29PL7-1
 
ATCO 12-Apr-27 10:00 19-Apr-27 17:00 175 Hours
Continuous
7L22 (790s Poplar Hill - 7L88 tap) Cut open 7L22, connect new line section to new 2061S Dobbs
7L22/21B relay upgrades at 790S Poplar Hill and 811S Clairmont Lake
On completion energize new 2061S Dobbs substation
 
SUNCOR 14-Apr-27 14:00 23-Apr-27 18:00 220 Hours
Continuous
29EDD-65 29PT-0257 (29EDD-65), 29EDD-65 29-952-4812 (29EDD-65), 29EDD-65 29-952-4813 (29EDD-65), 29EDD-71 752-4624 (29EDD-71), 29EDD-71 752-4623 (29EDD-71), 29PL7-4 (29EDD-65 - 29EDD-71) Firebag: 29EDD65;29PT-257 & 29PL7-4 SYSTEM, 29EDD65 ;29PT-260 & 29PL7-4 SYSTEM, 29EDD71 29PT-241 & 29PL7-4  
ALTALINK 19-Apr-27 06:30 28-Apr-27 18:00 227.5 Hours
Continuous
77s 652 (77s Sagitawah), 77s 752 (77s Sagitawah), 77s 40 (77s Sagitawah), 77s 57 (77s Sagitawah), 77s T2 (77s Sagitawah), 77s 29 (77s Sagitawah) Protection Upgrade 77sT2  
SUNCOR 20-Apr-27 09:00 23-Apr-27 20:00 83 Hours
Continuous
29EDD-1 29EDD1s952 (29EDD-1 Millennium) 29EDD1s952 - faulty SF6 sensors BPC-26-014 - 300677553  
ATCO 03-May-27 09:00 17-May-27 17:30 344.5 Hours
Continuous
2075s T11 (2075s Newell) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 344.5 Hours
Continuous
2029s T11 (2029s Heathfield) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 344.5 Hours
Continuous
13L50 (2029s Heathfield - 2075s Newell) Annual EATL outage at 2075s & 2029s.
**1218 IS NOT THE ISOALTION. ATCO SENT AESO OF REQUIRED ISOLATIONS BACK IN MAY 2024 TO UPDATE 2029S AND 2075S ISOLATIONS FOR 13L50 OUTAGES**
 
ATCO 03-May-27 10:00 06-May-27 17:00 79 Hours
Continuous
7L22 (811s Clairmont Lake - 7L88 tap) 7L22/21B relay upgrade at 811S Clairmont Lake
Upon completion new 2061S Dobbs substation ready to energize
 
SUNCOR 04-May-27 09:00 07-May-27 20:00 83 Hours
Continuous
29EDD-1 29EDD1s852 (29EDD-1 Millennium) 29EDD1S852 Replace Densimeter  
SUNCOR 04-May-27 09:00 14-May-27 20:00 251 Hours
Continuous
29EDD-34 29PS-214 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34), 29EDD-34 29PS-215 (29EDD-34), 29EDD-34 29PS-213 (29EDD-34) 29EDD34;29PL9-13 SYSTEM;PM 5y,10y  
ATCO 10-May-27 10:00 11-May-27 17:00 31 Hours
Continuous
7L03 (749s Flyingshot Lake - 7L09 tap) Cutover and commission RAS analogs and LTO to 790S Poplar Hill RAS Hub  
SUNCOR 11-May-27 09:00 14-May-27 20:00 83 Hours
Continuous
29EDD-1 29EDD1s1052 (29EDD-1 Millennium) 29EDD1S1052 Densimeter Replacement - No visibility outage, no line outage - BPC-26-017 - 300347749  
ATCO 12-May-27 10:00 13-May-27 17:00 31 Hours
Continuous
7L03 (731s Elmworth - 7L09 tap) Cutover and commission LTO to 790S Poplar Hill RAS Hub  
ATCO 14-May-27 10:00 15-May-27 17:00 31 Hours
Continuous
7L69 (731s Elmworth - 815s Goodfare) Cutover and commission LTO to 790S Poplar Hill RAS Hub  
ATCO 16-May-27 10:00 17-May-27 17:00 31 Hours
Continuous
7L07 (790s Poplar Hill - 815s Goodfare) Cutover and commission LTO to 790S Poplar Hill RAS Hub  
ATCO 28-May-27 10:00 31-May-27 18:00 80 Hours
Continuous
959s 708 (959s Lanfine), 959s 707 (959s Lanfine), 7L238 (959s Lanfine - 601s Bufallo Bird) Cutover CT/PT ccts, Commission new RAS A-B/7L238, end-to-end testing with 601S Buffalo Bird  
SUNCOR 01-Jun-27 08:00 10-Jun-27 17:00 225 Hours
Continuous
635EDD-1000 635-752-635PT-1000 (635EDD-1000), 635EDD-1000 635PT-1000 (635EDD-1000) FH - Maintenance on Transformer, associated breakers, other equipment in isolation boundary and protection system testing.  
SUNCOR 01-Jun-27 09:00 11-Jun-27 20:00 251 Hours
Continuous
29EDD-94 407T (29EDD-94 Voyageur), 29EDD-94 29-952-9705 (29EDD-94 Voyageur), 29EDD-94 29PS-393 (29EDD-94 Voyageur), 29EDD-94 29PS-392 (29EDD-94 Voyageur), 29EDD-94 29-952-9704 (29EDD-94 Voyageur), 29EDD-94 29PS-400 (29EDD-94 Voyageur) 29EDD94;29PT-407 SYSTEM;PM 5y,10y  
ATCO 07-Jun-27 10:00 10-Jun-27 17:00 79 Hours
Continuous
9L24 (946s Oakland - 959s Lanfine), 959s 906 (959s Lanfine), 959s 905 (959s Lanfine), 946s 902 (946s Oakland), 946s 903 (946s Oakland) Cutover Bkr/MOD status, Commission new LTO/RAS 204 A/B - Lanfine/Oakland  
ATCO 07-Jun-27 12:00 10-Jun-27 15:00 75 Hours
Continuous
7L80 (733s Simonette - 857s Kakwa Ridge), 733s 701 (733s Simonette) BREAKER SF6 HPL COMPLETE TESTING - 701 @ 733S  
SUNCOR 11-Jun-27 08:00 20-Jun-27 17:00 225 Hours
Continuous
635EDD-1000 635-752-635PT-1001 (635EDD-1000), 635EDD-1000 635PT-1001 (635EDD-1000) FH - Maintenance on Transformer, associated breakers, other equipment in isolation boundary and protection system testing.  
ATCO 11-Jun-27 10:00 12-Jun-27 17:00 31 Hours
Continuous
959s 901T (959s Lanfine), 959s 904 (959s Lanfine), 959s 919 (959s Lanfine), 959s 701 (959s Lanfine), 959s 706 (959s Lanfine), 959s 722 (959s Lanfine), 959S 722C (959S Lanfine) Cutover MOD status, Commission inputs to RAS 204 A/B  
SUNCOR 15-Jun-27 09:00 25-Jun-27 20:00 251 Hours
Continuous
29EDD-94 406T (29EDD-94 Voyageur), 29EDD-94 29-952-9702 (29EDD-94 Voyageur), 29EDD-94 29PS-388 (29EDD-94 Voyageur), 29EDD-94 29PS-389 (29EDD-94 Voyageur), 29EDD-94 29PS-399 (29EDD-94 Voyageur) 29EDD94;29PT-406 SYSTEM;PM 5y,10y  
ATCO 21-Jun-27 09:00 22-Jun-27 17:00 32 Hours
Continuous
730s 703 (730s Rycroft), 7L73 (730s Rycroft - 829s Boucher Creek) BREAKER SF6 HGF COMPLETE TESTING - 703 @ 730s  
AESO, ATCO 29-Jun-27 13:00 30-Jun-27 17:00 28 Hours
Continuous
9LA93 (973s Lanes Lake - 9L93 tap) Line to Ground Clearance Mitigation, Span 50-51. Repair deficiency on structure 57  
ATCO 19-Jul-27 10:00 22-Jul-27 15:00 77 Hours
Continuous
813s 906 (813s Little Smoky) BREAKER SF6 HGF COMPLETE TESTING - 906 @ 813S
Breaker 906 Counter Inoperable - Correct Counter Arm at 813s Little Smoky
 
ATCO 16-Aug-27 10:00 17-Aug-27 16:00 30 Hours
Continuous
815s 702 (815s Goodfare), 7L07 (790s Poplar Hill - 815s Goodfare) BREAKER SF6 LTB145D1/B COMPLETE TESTING - 702 @ 815S  
ATCO, ALTALINK 16-Aug-27 10:00 19-Aug-27 16:30 78.5 Hours
Continuous
7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO, ALTALINK 16-Aug-27 10:00 19-Aug-27 16:30 78.5 Hours
Continuous
702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ALTALINK, ATCO, FMGW 17-Aug-27 08:00 18-Aug-27 17:00 33 Hours
Continuous
964AL (1024s Granlea - 964L tap), 1024s PT-6001 (1024s Granlea), 1024s PT-6002 (1024s Granlea), 1024s 952-600001 (1024s Granlea), 1024s PS-6005 (1024s Granlea), 1024s PS-6006 (1024s Granlea), 1024s PS-6007 (1024s Granlea), 1024s PS-6008 (1024s Granlea), 1024s 489-600201 (1024s Granlea) maintenance activities (testing and inspection) of electrical equipment  
ATCO, ALTALINK 20-Aug-27 10:00 27-Aug-27 16:30 78.5 Hours
Continuous
702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ALTALINK, BCH 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous
1201L (520s Bennett - BCH Cranbrook), Path 1 (AIES Islanding) annual maintenance AB-BC
ALTALINK, BHE 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous
MATL (120s Picture Butte - Montana) align with 1201L outage AB-MATL
ALTALINK, BCH 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous
48s 887X (48s Pocaterra), 887L (48s Pocaterra - 978s BCH Britt Creek) opened because 1201L is out of service . AB-BC
ALTALINK, BCH 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous
799s 786W (799s Coleman), 786L (799s Coleman - BCH Natal) opened because 1201L is out of service. AB-BC
ATCO, ALTALINK 23-Aug-27 10:00 27-Aug-27 16:30 78.5 Hours
Continuous
7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 08-Nov-27 09:00 11-Nov-27 17:00 80 Hours
Continuous
ALC02L (409s Shell Scotford - 879s Upgrader) Install new Deadend corner structure on ALC02L  
ATCO 08-Nov-27 09:00 11-Nov-27 17:00 80 Hours
Continuous
ALC01L (408s Air Liquide Scotford - 409s Shell Scotford) Install new Deadend corner structure on ALC02L.  
ATCO 08-Feb-28 09:00 10-Feb-28 17:00 56 Hours
Continuous
7L228 (845s Big Mountain - 7L20 tap) AESO project P2716 - Install 7L228 bypass to facilitate the installation of new line switches for the new 7LA228 T-tap line connection to the new 2103S Pakenham substation
Open 7L228, replace structures 551 and 551A, connect bypass.
 
ATCO 06-Mar-28 10:00 22-Mar-28 16:00 389 Hours
Continuous
826s 903 (826s Marguerite Lake), 826s 907 (826s Marguerite Lake), 826s 901T (826s Marguerite Lake) Expand 240kV ring bus for new 9L42 line  
ATCO 13-Mar-28 10:00 16-Mar-28 17:00 79 Hours
Continuous
9L939 (77s Sagitawah - 809s Louise Creek) Cut over 9L939 to temp bypass structures to allow for installation of new deadend corner towers. These are required to make the final connections to the new 2105S Jackson substation  
ATCO 14-Mar-28 09:00 16-Mar-28 17:00 56 Hours
Continuous
7L228 (845s Big Mountain - 7L20 tap) AESO project P2716 - Disconnect bypass, connect new 7LA228D1 to 7LA228 Str #2, connect 7L228 to 7L228D2, connect 7L228 to 7L228D3. Renumber existing line switches 7L228D2 - D4, 7L228D3 - D5, 7L228D4 - D6
Commission DTT
 
ATCO 17-Mar-28 10:00 17-Apr-28 17:00 751 Hours
Continuous
9L938 (77s Sagitawah - 809s Louise Creek) Install foundations (TBD assume concrete), assemble and erect new Q-towers 9L938/9L939-155A and 9L938/9L939-156A in existing ROW centreline. Daily outage until such a time as the new towers begin to encroach on 9L938.  
ATCO 20-Mar-28 09:00 23-Mar-28 17:00 80 Hours
Continuous
2091s 704 (2091s Thornton) AESO project P2716 - cut over new SEL 2440 wiring at 2091S, relay programming, commission DTT and LTO  
ATCO 24-Mar-28 09:00 27-Mar-28 17:00 80 Hours
Continuous
740s 704 (740s H.R. Milner), 7L20 (740s H.R. Milner - 810s Dome Cutbank) AESO project P2716 - cut over RAS #171 wiring at 740S, relay programming, commission LTO 7L20/7L228  
SUNCOR 04-Apr-28 08:00 07-Apr-28 19:00 83 Hours
Continuous
29PL9-16 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT418/29PL9-16 SYSTEM;PM 5y,10y
 
ATCO 18-Apr-28 10:00 25-Apr-28 17:00 175 Hours
Continuous
9L938 (77s Sagitawah - 809s Louise Creek) Open 9L938 conductors, complete assembly and connect to the new Q-Towers 9L938/9L939-155A and 9L938/9L939-156A, string to 2105S Jackson deadend and terminate.
Relabel 9L938 segment from 809S Louise Creek to 2105S Jackson to 9L140.
 
ATCO 01-May-28 10:00 04-May-28 17:00 79 Hours
Continuous
9L939 (77s Sagitawah - 809s Louise Creek) Disconnect 9L939 conductors from temp structure 9L939 -155A - 155E reconnect to existing structures 9L938/9L939-156 and 9L938/9L939-155, connect to the new Q-Towers 9L938/9L939-155A and 9L938/9L939-156A, string to 2105S Jackson deadend and terminate.
Relabel 9L939 segment from 809S Louise Creek to 2
 
SUNCOR 03-May-28 14:00 12-May-28 18:00 220 Hours
Continuous
29EDD-65 29PT-0236 (29EDD-65), 29EDD-65 29-952-4823 (29EDD-65), 29EDD-65 29-952-4822 (29EDD-65), 29EDD-71 752-4634 (29EDD-71), 29EDD-71 752-4633 (29EDD-71), 29PL7-3 (29EDD-65 - 29EDD-71) Firebag: 29EDD65;29PT-236 & 29PL7-3 SYSTEM, 29EDD65;29PT-250&29PL7-3 SYSTEM, 29PT-246 SYSTEM;29EDD71  
ATCO 08-May-28 09:00 10-Jul-28 17:00 1,520 Hours
Continuous
959s 240kV Bus 900BS2 (959s Lanfine) GOI on 9L141 until line terminated into 1162S Fair Acres and ready to energize  
ATCO 08-May-28 09:00 10-Jul-28 17:00 1,520 Hours
Continuous
959s 240kV Bus 900BS2 (959s Lanfine) GOI on 902/903 until line terminated and 1162S Fair Acres ready to energize  
ATCO 09-May-28 10:00 13-May-28 17:00 103 Hours
Continuous
9L02 (809s Louise Creek - 813s Little Smoky) Install concrete foundations for new structures 9L02/320A, 320H in preparation to cut into 9L02 and convert to a t-tap.  
ATCO 15-May-28 09:00 17-May-28 17:00 56 Hours
Continuous
959s 240kV Bus 900BS1 (959s Lanfine) Connect new bus from new 902B to existing switch 901A to add new line 9L141,
Cutover and commission 900PT1 ccts to new 9L141 relays
 
ATCO 18-May-28 09:00 20-May-28 17:00 56 Hours
Continuous
959s 240kV Bus 900BS2 (959s Lanfine) Connect new bus from new Bkr 903 to existing switch 903B to add new line 9L141,
Cutover and commission 900PT2 ccts to new 9L141 relays
 
ATCO 29-May-28 09:00 08-Jun-28 17:00 248 Hours
Continuous
9L24 (946s Oakland - 959s Lanfine) Cutover and commission 905/906 CT's, 9L24PT ccts to new RAS 241 SEL 451A/B relays @ 959S Lanfine and update relay settings for RAS 241 and SCADA inputs @946S Oakland.  
ATCO 19-Jun-28 10:00 30-Jun-28 16:00 270 Hours
Continuous
9L20 (755s Cordel - 766s Nevis)
Install concrete foundations at 9L20 Structure 69 for new T-Tap connection
 
ATCO 26-Jun-28 10:00 10-Jul-28 17:00 343 Hours
Continuous
9L02 (809s Louise Creek - 813s Little Smoky) Cut into 9L02 and connect new t-tap structures for 9LA02.
9L02-21A and 21B relay upgrades at 809S Louise Creek and 813S Little Smoky. Implement RAS
Energize new line 9LA02 and 884S Magpie substation
 
ATCO 31-Jul-28 10:00 15-Aug-28 16:00 366 Hours
Continuous
766s 901 (766s Nevis), 9L20 (755s Cordel - 766s Nevis), 755s 906 (755s Cordel), 755s 901 (755s Cordel)
Cutover new 9L20 line section, terminate 9LA20 at customer substation. Install new line protection relays
 
ATCO 01-Oct-28 08:00 21-Oct-28 16:00 488 Hours
Continuous
972s 904 (972s Tinchebray) CETO project
Install 904 and 904CT

Commission 904 and 904CT

Expand GOI to 900BS1
Isolation Points: 904A, 901A and 900SST1X
Connect 907B to 900BS1
Shrink GOI to 907B
 
ATCO 22-Oct-28 08:00 20-Nov-28 16:00 705 Hours
Continuous
972s 906 (972s Tinchebray) CETO project
Install 906 and 906CT

Commission 906 and 906CT

Expand GOI to 900BS2 OCT 22 2028 - NOV 20 2028
Isolation Points: 906A, 902B and 9L16D1@ CORDEL
Connect 909A to 900BS2
Commission Logic and breaker fail
Shrink GOI to 9L86D1
String 9L86 into substation
 

AB-BC, AB-SK & AB-MATL: refer to AESO web posting: http://itc.aeso.ca/itc/public/atc
Also,
AB-BC, AB-SK & AB-MATL: refer to ISO Rule 203.6: http://www.aeso.ca/rulesprocedures/18592.html

Prepared On: 2026-09-09   15:39:12


This document and the information contained herein are based upon information and data which by their nature contain a degree of uncertainty and are subject to change. In addition, this document may contain information and data from public sources and/or third parties, which have been assumed to be accurate and complete and have not been verified. Accordingly, the Independent System Operator, operating as the Alberta Electric System Operator (the "AESO") makes no warranty, representation or guarantee, express or implied, with respect to this document or the information contained herein, including, but not limited to, any warranty, representation or guarantee of accuracy, completeness, timeliness, reliability, availability, absence of computer virus, non- infringement, merchantability or suitability for any purpose. Under no circumstances will the AESO, its members, officers, employees, contractors or agents, or any of their respective affiliates, be liable for any errors or omissions in, or any losses, damages or claims whatsoever, whether in contract, tort or otherwise, arising from use of or reliance upon, this document or any information contained herein.

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