Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2026-05-02

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.

Previous Version
Download CSV

Owner From To Duration Element Scheduled Activity Affected Intertie
ATCO 25-Nov-25 17:46 18-Sep-26 18:00 296.97 Days
Continuous
876s 901T (876s Brintnell) forced outage oil leaking  
SUNCOR 04-Jan-26 08:00 02-Sep-26 16:00 241.29 Days
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  
BHE Canada 22-Mar-26 13:00 30-Jun-26 17:00 100.17 Days
Continuous
120s C1 (120s Picture Butte), 120s C2 (120s Picture Butte) forced outage  
ALTALINK 30-Mar-26 08:30 04-May-26 16:30 35.33 Days
Continuous
62s T1 (62s Brazeau Plant), 62s 1 (62s Brazeau Plant) maintenance  
EPCOR 13-Apr-26 07:00 29-May-26 17:00 46.42 Days
Continuous
805s T4 (805s Jasper) bushing replacement and fan repair  
BCH 20-Apr-26 09:00 08-May-26 17:00 18.33 Days
Continuous
5L98 (BCH Nicola - BCH Vaseux Lake) replace spacer damper and insulator, BC maintenance does not affect the Alberta ATC AB-BC
ALTALINK, ATCO 27-Apr-26 08:00 11-May-26 18:00 14.42 Days
Continuous
87s T2 (87s Gaetz), 87s 240kV East Bus (87s Gaetz), 87s 1552 (87s Gaetz), 87s 1652 (87s Gaetz), 87s 1952 (87s Gaetz), 87s 1252 (87s Gaetz), 962L (87s Gaetz - 972s Tinchebray), 986L (87s Gaetz - 972s Tinchebray) Closing Open points 'A' & 'C' and commissioning 87s962 & 87s986 MODs  
ATCO 27-Apr-26 12:00 04-May-26 12:00 7 Days
Continuous
730s STATCOM (730s Rycroft), 730s 705 (730s Rycroft), 730s 702T (730s Rycroft) svc fire system and annual inspection @ Rycroft 730s  
ALTALINK 29-Apr-26 08:00 07-May-26 18:00 8.42 Days
Continuous
275s T1 (275s Jenner) 275sT1 Oil Reclaim, Maintenance, Plugged Radiator, Replace switch 275s37 and 275s39. Replace 25kV post insulators.275s2269, 275s2036N, & 275s81  
ALTALINK 29-Apr-26 17:00 19-May-26 07:00 19.58 Days
Continuous
320p 2089 (320p Keephills) Urgent customer work on G3  
ALTALINK 01-May-26 14:00 07-May-26 16:00 6.08 Days
Continuous
37s Protection & Control (37s North Calder), 37s T6 (37s North Calder) P&C upgrades (37s4, 37s88, 37s81, T6, PT20)  
ENMAX 02-May-26 08:00 02-May-26 18:00 10 Hours
Continuous
162.1TR (SS-162), 240kV North Bus (SS-162), 138kV North Bus (SS-162) Summer Substation Washing  
ENMAX 03-May-26 08:00 03-May-26 18:00 10 Hours
Continuous
162.2TR (SS-162), 138kV South Bus (SS-162), 240kV South Bus (SS-162) Summer Substation Washing  
EPCOR 04-May-26 07:00 08-May-26 17:00 4.42 Days
Continuous
805s T4 (805s Jasper), EP 805s J2406 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: TX4 Relay Maintenance  
EPCOR 04-May-26 07:00 10-May-26 17:00 6.42 Days
Continuous
BR721 (Rossdale), 814s T1 (814s Bellamy), 814s B2401 (814s Bellamy), 814s B2407 (814s Bellamy) Bellamy: TX1 Zone Doble and BR721 Breaker Maintenance/Doble, and BDS15 Disconnect Maintenance  
EPCOR 04-May-26 07:00 10-May-26 17:00 6.42 Days
Continuous
557s T2 (557s Castle Downs), 557s CD2403 (557s Castle Downs), 557s CD2404 (557s Castle Downs) Castledowns: TX2 Doble, Tap Changer Maintenance, and CDAB2CDDS6/CDDS7 Disconnect Maintenance  
BCH, BPA 04-May-26 08:00 15-May-26 17:00 11.38 Days
Continuous
2L112 (BPA Boundary - BCH Nelway) emergency replacement of a boundary PCB AB-BC
Syncrude 04-May-26 08:00 24-May-26 16:00 20.33 Days
Continuous
Mildred T6 (Syncrude Mildred Lake), 635 (Syncrude Mildred Lake) SCL - repair tap changer in T6 transformer  
ATCO 04-May-26 09:00 18-May-26 17:30 14.35 Days
Continuous
13L50 (2029s Heathfield - 2075s Newell) Kinbrook Addition to 2075s  
ATCO 04-May-26 09:00 18-May-26 17:30 14.35 Days
Continuous
2029s T11 (2029s Heathfield) Kinbrook Addition to 2075s Newell.  
ATCO 04-May-26 09:00 18-May-26 17:30 14.35 Days
Continuous
2075s T11 (2075s Newell) Kinbrook Addition to 2075s Newell.  
ALTALINK 04-May-26 10:00 04-May-26 15:00 5 Hours
Continuous
254s 35 (254s Coaldale), 254s T2 (254s Coaldale) Repair/Complete lightning arrestor grounding on T2 (TX18710)  
ATCO 04-May-26 10:00 07-May-26 10:00 3 Days
Continuous
9L19 (937s AMR02 - 960s Birchwood Creek), 937s 06-TR-8001A (937s Amr02), 937s 06-DS-89T1 (937s Amr02), 937s 9L19 (937s Amr02) transformer and disconnect maintenance  
ATCO, CNRL 04-May-26 10:00 08-May-26 16:00 4.25 Days
Continuous
838s RTU/SCADA (838s Horizon Mining), 842s RTU/SCADA (842s Horizon Upgrading) Brief SCADA Outages(15-30min) while RTU updates are completed.  
ATCO, ALTALINK 04-May-26 11:00 05-May-26 17:00 30 Hours
Continuous
953L (574s Nilrem - 755s Cordel) Transmission line maintenance  
BCH 05-May-26 09:00 06-May-26 17:00 1.33 Days
Continuous
5L98 (BCH Nicola - BCH Vaseux Lake) NIC 5CB51 rebuild AB-BC
ATCO 05-May-26 09:00 07-May-26 17:00 2.33 Days
Continuous
972s 901 (972s Tinchebray)
Connect 900BS1 to new 907B
Cutover 900SST1 Non Elec trips to new 900BS1 protection
Cutover 901CT and 901 trips to new 900BS1 protection
 
ATCO 05-May-26 12:00 08-May-26 12:00 3 Days
Continuous
786s SVC (786s High Level) SVC AIR COOLED MAINTENANCE @ HIGH LEVEL 786S  
ALTALINK 06-May-26 08:00 06-May-26 16:00 8 Hours
Continuous
132s 37 (132s Ware Junction), 132s 40 (132s Ware Junction), 275s 1852 (275s Jenner), 275s 1752 (275s Jenner), 951L (132s Ware Junction - 275s Jenner) Center phase socket clevis that holds yolk plate has a keeper key backed out str 164  
ALTALINK, Lethbridge 06-May-26 08:00 06-May-26 16:00 8 Hours
Continuous
734L (241s Uplands - 370s North Lethbridge) 734L Open End Outage at 241S to Cutover CT Circuits for NEW DDR Installation & Test.
 
ENMAX 06-May-26 08:00 07-May-26 16:00 1.33 Days
Continuous
12B138-832L (SS-12), 832L (SS-10 - SS-12) HV Breaker Maintenance  
ATCO, ALTALINK 06-May-26 08:00 07-May-26 17:00 1.38 Days
Continuous
948L (650s Hansman Lake - 863s Paintearth) Transmission line maintenance  
ATCO, GREENGATEP 07-May-26 09:00 19-May-26 17:00 12.33 Days
Continuous
9L16 (755s Cordel - 972s Tinchebray) GOI is required on 907B to isolate 908/909 bay and new 9L16.
**THERE IS NO OUTAGE TO 9L16 UNTIL MAY 19, 2026
 
ATCO 07-May-26 10:01 10-May-26 17:30 3.31 Days
Continuous
9L28 (937s AMR02 - 960s Birchwood Creek), 937s 06-TR-8001B (937s Amr02), 937s 9L28 (937s Amr02), 937s 06-DS-89T2 (937s Amr02) transformer and disconnect maintenance  
ALTALINK, EPCOR 07-May-26 14:00 14-May-26 17:00 7.13 Days
Continuous
37s Protection & Control (37s North Calder), 37s 88 (37s North Calder), 37s 82 (37s North Calder), 920L (37s North Calder - 557s Castle Downs) P&C upgrades (37s88, 37s82, PT21)  
ATCO 08-May-26 09:00 09-May-26 17:00 1.33 Days
Continuous
972s 240kV Bus 900BS2 (972s Tinchebray) Connect new 909A to 900BS2  
ENMAX 09-May-26 07:00 09-May-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  
ALTALINK 09-May-26 07:00 13-May-26 18:00 4.46 Days
Continuous
336s 612 (336s Fincastle), 368s 612 (368s Burdett), 612L (336s Fincastle - 368s Burdett) Replacing cross arms and insulators on structures 174, 196, 197, 198, 203, 205, 206, 207, 208, 209, 210, 211, and 212  
ENMAX, ALTALINK 09-May-26 12:00 09-May-26 18:00 6 Hours
Continuous
162B138-RB80 (SS-162), 162B138-RB81 (SS-162), 162.81L (391s Balzac - SS-162) Summer Substation Washing  
ALTALINK, ENMAX 09-May-26 12:00 09-May-26 18:00 6 Hours
Continuous
391s 162.81 (391s Balzac), 162.81L (391s Balzac - SS-162) Summer Substation Washing  
ENMAX, ALTALINK 10-May-26 08:00 10-May-26 12:00 4 Hours
Continuous
162B240-RB133 (SS-162), 918L (281s Johnson - SS-162), 162B240-RB132 (SS-162) Summer Substation Washing  
ENMAX, ALTALINK 10-May-26 08:30 10-May-26 12:00 3.5 Hours
Continuous
918L (281s Johnson - SS-162) Enmax Summer Substation Washing  
ENMAX, ALTALINK 10-May-26 12:00 10-May-26 18:00 6 Hours
Continuous
932L (74s Janet - SS-162), 162B240-RB136 (SS-162), 162B240-RB135 (SS-162) Summer Substation Washing  
ENMAX, ALTALINK 10-May-26 12:30 10-May-26 18:00 5.5 Hours
Continuous
932L (74s Janet - SS-162) Enmax Summer Substation Washing  
EPCOR 11-May-26 07:00 11-May-26 13:00 6 Hours
Continuous
987s GT3 (987s Clover Bar) Cloverbar: G3 Outage, CPC Request  
ATCO, ALTALINK 11-May-26 07:00 14-May-26 18:00 3.46 Days
Continuous
7LA114 (658s Chard - 7L114 tap), 7L114 (72s Leismer - 7LA114 tap), 7L114 (907s Waddell - 7LA114 tap), 907s Waddell AltaLink outage on 72sT2 causing an outage to 7L114 at 907S  
ALTALINK 11-May-26 07:00 14-May-26 18:00 3.46 Days
Continuous
72s T2 (72s Leismer), 72s 1052 (72s Leismer) Transformer maintenance, doble, install Coresense & Qualitrol. 1st trips and breaker maintenance on 72s1052.  
EPCOR 11-May-26 07:00 17-May-26 17:00 6.42 Days
Continuous
814s T2 (814s Bellamy), BR722 (Rossdale), 814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy) Bellamy: TX2 Zone Doble and BR722 Breaker Maintenance/Doble, and BDS17 Disconnect Maintenance  
EPCOR 11-May-26 07:00 22-May-26 17:00 11.42 Days
Continuous
52s T1 (52s East Industrial) East Industrial: TX1 DGA Monitor Replacement  
ENMAX 11-May-26 08:00 12-May-26 16:00 1.33 Days
Continuous
12B138-833L (SS-12), 833L (SS-2 - SS-12) HV Breaker Maintenance  
ALTALINK, ATCO 11-May-26 08:00 14-May-26 16:00 3.33 Days
Continuous
72s 1052 (72s Leismer), 7L114 (72s Leismer - 7LA114 tap) Customer maintenance  
ATCO, ALBIAN 11-May-26 09:00 12-May-26 15:00 30 Hours
Continuous
920s 901T (920s Jackpine) Isolation of 901T for CNRL to troubleshoot problems on their system  
ATCO 11-May-26 13:00 14-May-26 13:00 3 Days
Continuous
827s SVC (827s Cranberry Lake) SVC AIR COOLED MAINTENANCE
SVC AUX TRIP RELAY TESTING
SVC MICROPROCESSOR RELAY TESTING
SPR TESTING - TRANSFORMER 703T
TRIP COIL TESTING 401, 703
 
ATCO, ALTALINK, ENBRIDGE 11-May-26 13:00 14-May-26 13:00 3 Days
Continuous
7L114 (72s Leismer - 7LA114 tap), 7LA114 (658s Chard - 7L114 tap), 7L114 (907s Waddell - 7LA114 tap) Planned inspection on 7L114/7LA114 to take place during the AltaLink outage to their T2 transformer at 72S  
ALTALINK 11-May-26 13:30 14-May-26 17:00 3.15 Days
Continuous
38s 7452 (38s East Edmonton) 240kV breaker maintenance  
ATCO, ALTALINK 11-May-26 18:00 06-Jun-26 16:30 25.94 Days
Continuous
962L (87s Gaetz - 972s Tinchebray) Switch needs to remain open until ATCO is ready @ 972s for energization  
ATCO, ALTALINK 11-May-26 18:00 06-Jun-26 16:30 25.94 Days
Continuous
986L (87s Gaetz - 972s Tinchebray) Switch needs to remain open until ATCO is ready @ 972s for energization  
ALTALINK 12-May-26 07:15 12-May-26 17:45 10.5 Hours
Continuous
1206L (12s Heartland - 89s Ellerslie) Transmission line maintenance  
ALTALINK 12-May-26 08:00 12-May-26 17:00 9 Hours
Continuous
77s 26 (77s Sagitawah) 240kV breaker maintenance  
ALTALINK, ICPCL 12-May-26 08:00 13-May-26 17:00 1.38 Days
Continuous
225s 225E (225s Magrath), 67s 225 (67s Stirling), 225AL (313s Raymond Reservoir - 225L tap), 225L (225s Magrath - 225AL tap), 225L (67s Stirling - 225AL tap) 93, 149 replace arms and insulators  
Syncrude 12-May-26 08:00 23-May-26 16:00 11.33 Days
Continuous
211 (Aurora), 213 (Aurora), 212B (Aurora), 213A (Aurora), 89-215 (Aurora) Zone 5 6yr PM  
ALTALINK 13-May-26 08:00 13-May-26 17:00 9 Hours
Continuous
77s 40 (77s Sagitawah) 240kV breaker maintenance  
ATCO, ALBIAN 13-May-26 09:00 14-May-26 15:00 30 Hours
Continuous
920s 902T (920s Jackpine) Isolation of 902T for CNRL to troubleshoot problems on their system  
ALTALINK 14-May-26 08:00 14-May-26 17:00 9 Hours
Continuous
321s 880 (321s Al Rothbauer), 523s 880 (523s Bullshead), 880L (321s Al Rothbauer - 523s Bullshead) Re-installing damper on structure 4
Re-tying OHSW's on structure 8
 
ATCO, ALBIAN, CNRL 14-May-26 08:00 29-May-26 16:00 15.33 Days
Continuous
919s 908 (919s Hartley), 847s 902T (847s Muskeg River) CNRL Request
COG to open 908 breaker and 902TD in the Hartley 919S substation at CNRL Albian Sands.
 
SUNCOR 18-May-26 08:00 24-May-26 20:00 6.5 Days
Continuous
29PL9-12 (29EDD-34 - 29EDD-65) 29EDD34;29PL9-12 SYSTEM;PM 5y,10y
 
EPCOR 19-May-26 07:00 19-May-26 17:00 10 Hours
Continuous
T2 (Poundmaker), PM2405 (Poundmaker), PM2401 (Poundmaker) Poundmaker: TX2 Zone, PMAB2 Repair  
EPCOR 19-May-26 07:00 22-May-26 17:00 3.42 Days
Continuous
557s T1 (557s Castle Downs) Castledowns: TX1 Tapchanger Maintenance/Testing and Conservator Pipe Leak Repair  
EPCOR 19-May-26 07:00 01-Jun-26 07:00 13 Days
Continuous
T1 (Rossdale), R721 (Rossdale), RR723 (Rossdale), BR722 (Rossdale), 814s T2 (814s Bellamy) Rossdale: TX1 LCR Demo  
ALTALINK 19-May-26 08:00 22-May-26 10:05 3.09 Days
Continuous
254s 172E (254s Coaldale), 83s 172W (83s Taber), 172L (254s Coaldale - 172EL tap), 172L (83s Taber - 172EL tap) 172L outage to facilitate the opening of 172EL1 which is required to be opened de-energized.  
ALTALINK, ACCIONA 19-May-26 08:30 22-May-26 17:00 3.35 Days
Continuous
172EL (139s Hillridge - 172L tap) Site coming offline to perform minor preventative maintenance. This includes SAB-1 and all downstream components (52-T1, 52-F1, 52-F2, 52-F3)  
ATCO 19-May-26 09:00 19-May-26 17:00 8 Hours
Continuous
9L16 (755s Cordel - 972s Tinchebray), 755s 904 (755s Cordel), 755s 905 (755s Cordel), 972s 903 (972s Tinchebray) Disconnect 9L16 from existing A-frame deadend and 9L16D2 (to be renamed 9L86D1)
Restore bus leave renamed 9L86D1 open for future line connection.
 
BCH, BPA 19-May-26 09:00 20-May-26 17:00 1.33 Days
Continuous
5L52 (BPA Custer - BCH Ingledow) Glass replacement AB-BC
BCH, BPA 19-May-26 09:00 23-May-26 17:00 4.33 Days
Continuous
5L52 (BPA Custer - BCH Ingledow) doble and inspection 5CB5 AB-BC
ATCO 19-May-26 09:00 29-May-26 17:00 10.33 Days
Continuous
9L16 (755s Cordel - 972s Tinchebray) Disconnect 9L16 from existing A-frame deadend and 9L16D2 (to be renamed 9L86D1)
Restore bus leave renamed 9L86D1 open for future line connection.
 
ALTALINK 19-May-26 13:00 21-May-26 16:00 2.13 Days
Continuous
525s 851X (525s Carseland), 851L (253s Blackie - 525s Carseland) 525s851X PRC5 Breaker maintenance.  
ALTALINK 19-May-26 23:00 21-May-26 07:00 1.33 Days
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 20-May-26 07:00 21-May-26 07:00 24 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
BCH 20-May-26 08:00 21-May-26 16:00 1.33 Days
Continuous
T3 (BCH Natal) inspection/doble AB-BC
BCH 20-May-26 08:00 21-May-26 16:00 1.33 Days
Continuous
2L113 (BCH Cranbrook - BCH Natal) install marker balls AB-BC
ALTALINK, ALPAC 20-May-26 08:30 20-May-26 18:00 9.5 Hours
Continuous
796L (282s Grassland - 796AL tap) Customer maintenance @ 282s  
ALTALINK 20-May-26 09:00 28-May-26 17:00 8.33 Days
Continuous
275s T2 (275s Jenner) 275sT2 Oil Reclaim and Maint. Replace switches 275s45, 275s49, 275s47. Replace 25kV Post Insulators. 275s2323, 275s167W  
ATCO, CNRL 22-May-26 11:01 22-May-26 12:59 118 Mins
Continuous
9L32 (941s Bitumount - 2005s Secord), 9L32 (838s Horizon Mining - 941s Bitumount) MUST TAKE 9L32 OOS for telecom worl 1-00509997 and 1-00510463
 
ALTALINK, ACCIONA 22-May-26 16:05 22-May-26 17:35 90 Mins
Continuous
254s 172E (254s Coaldale), 83s 172W (83s Taber), 172EL (139s Hillridge - 172L tap), 172L (254s Coaldale - 172EL tap), 172L (83s Taber - 172EL tap) 172L out of service to close 172EL1  
ENMAX, ALTALINK 23-May-26 08:00 23-May-26 11:00 3 Hours
Continuous
5s T1 (5s East Calgary) Summer Substation Washing  
ENMAX, ALTALINK 23-May-26 08:00 23-May-26 12:00 4 Hours
Continuous
5s T1 (5s East Calgary) Summer Substation Washing  
ALTALINK, Lethbridge 23-May-26 08:00 24-May-26 17:00 1.38 Days
Continuous
207L (111s Coalbanks - 370s North Lethbridge) 207L Hardware tightening on structure 8 and 11  
ATCO 23-May-26 10:00 26-May-26 10:00 3 Days
Continuous
9L19 (937s AMR02 - 960s Birchwood Creek) Customer request - Disconnect Switch Maintenance  
ENMAX, ALTALINK 23-May-26 11:00 23-May-26 13:00 2 Hours
Continuous
5s T2 (5s East Calgary) Summer Substation Washing  
ENMAX, ALTALINK 23-May-26 11:00 23-May-26 14:00 3 Hours
Continuous
5s T2 (5s East Calgary) Summer Substation Washing  
Syncrude 24-May-26 08:00 07-Jun-26 16:00 14.33 Days
Continuous
334 (Syncrude Mildred Lake), 335 (Syncrude Mildred Lake), 3235 (Syncrude Mildred Lake), Mildred T3 (Syncrude Mildred Lake), 234 (Syncrude Mildred Lake), 235 (Syncrude Mildred Lake), 2235 (Syncrude Mildred Lake), Mildred T2 (Syncrude Mildred Lake), Mildred T1 (Syncrude Mildred Lake), 135 (Syncrude Mildred Lake), 134 (Syncrude Mildred Lake), 1335 (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), 1934 (Syncrude Mildred Lake), 1935 (Syncrude Mildred Lake), Mildred T19 (Syncrude Mildred Lake), ML1 (D05 - Syncrude Mildred Lake), 914 (Syncrude Mildred Lake), 915 (Syncrude Mildred Lake), 916 (Syncrude Mildred Lake), 814 (Syncrude Mildred Lake), 815 (Syncrude Mildred Lake), 816 (Syncrude Mildred Lake), 1224A (Syncrude Mildred Lake), 1224B (Syncrude Mildred Lake), 1225 (Syncrude Mildred Lake), 19215 (Syncrude Mildred Lake), D05 76 (D05), D05 75B (D05), D05 76A (D05) SCL - Plant 31 6-Year 72kV "B" Bus PM
During the 72kV "B" Bus PM at Mildred Lake Plant 31,
 
ALTALINK, DOW 25-May-26 07:00 26-May-26 18:00 1.46 Days
Continuous
166s 787W (166s Dow Chemical Fort Saskatchewan), 71s 452 (71s Lamoureux), 71s 352 (71s Lamoureux), 906s 787AE (906s Ross Creek), 787AL (906s Ross Creek - 787L tap), 787L (166s Dow Chemical Fort Saskatchewan - 787AL tap), 787L (71s Lamoureux - 787AL tap) Replace Structure 787L30, 31,32 and D78269 with new configuration where proposed self-supporting 787L31 will be located in proximity to salvaged D782L69 and will support the OPGW  
EPCOR 25-May-26 07:00 27-May-26 17:00 2.42 Days
Continuous
816s P2401 (816s Petrolia) Petrolia: P2401 CT Doble  
EPCOR 25-May-26 07:00 05-Jun-26 17:00 11.42 Days
Continuous
987s T4 (987s Clover Bar), 987s C2408 (987s Clover Bar) Cloverbar: TX4 DGA Monitor Replacement and Relay Maintenance  
ATCO 25-May-26 09:00 27-May-26 17:30 2.35 Days
Continuous
2075s 911 (2075s Newell) BREAKER SF6 3AP4FI MAINTENANCE  
Lethbridge 25-May-26 10:00 25-May-26 14:00 4 Hours
Continuous
181s 172L (181s Chinook) 181s 172L Open End Outage to Cutover CT Circuits for NEW DDR Installation & Test "Initiate" Output circuit.  
ATCO 25-May-26 10:00 25-May-26 16:00 6 Hours
Continuous
898s 904 (898s Heart Lake) PRC-005 TRIP COIL TESTING, B PHASE MOTOR CCT DC FAIL TROUBLESHOOTING/ REPAIR

 
ATCO 25-May-26 10:00 26-May-26 16:00 30 Hours
Continuous
715s 701 (715s Leming Lake), 7L583 (715s Leming Lake - 970s Bourque) PRC-005 Trip Coil Testing, 701CT Inspection/ Testing  
ALTALINK 25-May-26 13:30 28-May-26 17:00 3.15 Days
Continuous
77s T1 (77s Sagitawah) PRC5 Transformer Maintenance, Doble, Leak repair & IDD replacement  
ALTALINK 25-May-26 14:00 06-Jun-26 17:00 12.13 Days
Continuous
63s 352 (63s Red Deer), 925L (63s Red Deer - 74s Janet) 63s352 Breaker Replacement to SF6 breaker.  
ATCO 26-May-26 08:00 26-May-26 09:59 119 Mins
Continuous
898s 901 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
Lethbridge 26-May-26 09:00 26-May-26 13:00 4 Hours
Continuous
181s 463L (181s Chinook) 181s 463L Open End Outage to Cutover CT Circuits for NEW DDR Installation & to Test "Initiate" Output circuits from required relays to DDR.  
ATCO 26-May-26 10:00 26-May-26 11:59 119 Mins
Continuous
898s 902 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
ATCO 26-May-26 12:00 26-May-26 13:59 119 Mins
Continuous
898s 903 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
ATCO 26-May-26 13:00 29-May-26 13:00 3 Days
Continuous
9L28 (937s AMR02 - 960s Birchwood Creek) Customer request - Disconnect Switch Maintenance  
ATCO 26-May-26 14:00 26-May-26 15:59 119 Mins
Continuous
898s 905 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
ATCO 27-May-26 08:00 27-May-26 09:59 119 Mins
Continuous
898s 906 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
ENMAX, ALTALINK 27-May-26 08:00 28-May-26 16:00 1.33 Days
Continuous
24.83L (74s Janet - SS-24) HV Breaker Maintenance. 24B138-24.83 Breaker Racking Support Install  
Syncrude 27-May-26 08:00 13-Jun-26 16:00 17.33 Days
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  
SUNCOR 27-May-26 09:00 01-Jun-26 20:00 5.46 Days
Continuous
29EDD-1 29EDD1S11 (29EDD-1 Millennium), 29EDD-1 29EDD1s552 (29EDD-1 Millennium), 29EDD-1 29EDD1s652 (29EDD-1 Millennium), 29EDD-3 29PT-6 (29EDD-3) 29EDD-1 29EDD1S11 Repair Broken Switch 29EDD1;29CVT-4 SYSTEM Protection testing, Breaker trip testing  
ATCO 27-May-26 10:00 27-May-26 11:59 119 Mins
Continuous
898s 908 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
ATCO 27-May-26 10:00 28-May-26 16:00 30 Hours
Continuous
715s 702 (715s Leming Lake), 7L91 (715s Leming Lake - 826s Marguerite Lake) PRC-005 Trip Coil Testing, 702CT Inspection/ Testing  
ATCO 27-May-26 11:00 29-May-26 11:00 2 Days
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 27-May-26 12:00 27-May-26 13:59 119 Mins
Continuous
898s 909 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
EPCOR 28-May-26 07:00 30-May-26 17:00 2.42 Days
Continuous
816s P2405 (816s Petrolia) Petrolia: P2405 CT Doble  
ATCO, ALTALINK 28-May-26 11:01 28-May-26 13:00 119 Mins
Continuous
898s 708 (898s Heart Lake), 788L (898s Heart Lake - 788AL tap) PRC-005 TRIP COIL TESTING  
ATCO 30-May-26 09:00 13-Jun-26 17:00 14.33 Days
Continuous
972s 905B (972s Tinchebray), 972s 906A (972s Tinchebray) Connect new 9L62 to 972S and prepare to energize.
String Conductors/OPGW 9L62 from Str #3 to substation A-frame deadends and connect to 9L62D1, coordinate with AML conductor jumpers and OPGW termination at the TFO boundary 9L86 Str 409
 
EPCOR 01-Jun-26 07:00 02-Jun-26 17:00 1.42 Days
Continuous
T1 (EP Riverview) Riverview: TX1 Secondary Cabinet Venting Install  
EPCOR 01-Jun-26 07:00 03-Jun-26 17:00 2.42 Days
Continuous
816s P2406 (816s Petrolia) Petrolia: P2406 CT Doble  
EPCOR 01-Jun-26 07:00 07-Jun-26 17:00 6.42 Days
Continuous
T4 (Poundmaker), PM721 (Poundmaker), PM2402 (Poundmaker), PM2403 (Poundmaker) Poundmaker: TX4 Doble and PMAB4/PMDS4/PMDS5 Disconnect Maintenance  
EPCOR 01-Jun-26 07:00 10-Jul-26 17:00 39.42 Days
Continuous
EP 805s J2403 (EP 805s Jasper) Jasper: J2403 Replacement LCR  
SUNCOR 01-Jun-26 08:00 05-Jun-26 20:00 4.5 Days
Continuous
29EDD-94 29PP-97 260kV Bus (29EDD-94 Voyageur) 29EDD94, 29PT-412B Oil Leak (29PP-97 260KV outage) - Leak repair and top up (9001051293) TDEC  
ALTALINK 01-Jun-26 08:00 11-Jun-26 15:00 10.29 Days
Continuous
19s 905 (19s Wabamun), 37s Protection & Control (37s North Calder), 37s 82 (37s North Calder), 37s 76 (37s North Calder), 905L (19s Wabamun - 37s North Calder) Protection upgrade  
ATCO 01-Jun-26 10:00 02-Jun-26 16:00 30 Hours
Continuous
715s 703 (715s Leming Lake), 7L66 (715s Leming Lake - 717s Ethel Lake) PRC-005 Trip Coil Testing, 703CT Inspection/ Testing  
ALTALINK 01-Jun-26 10:30 04-Jun-26 17:00 3.27 Days
Continuous
320p 91 (320p Keephills), 320p 1352 (320p Keephills), 320p 752 (320p Keephills), 320p 352 (320p Keephills), 320p 2152 (320p Keephills), 320p T1 (320p Keephills), 320p 240kV Bus B (320p Keephills), 1045AL (320p Keephills - 1045L tap) 320p91 Breaker Maintenance and 320p213 Switch repair  
ALTALINK 02-Jun-26 07:00 03-Jun-26 17:00 1.42 Days
Continuous
944L (132s Ware Junction - 275s Jenner) Telecom SIA specifies that a 944L and 944AL outage is required for dish realignment. Both A and B protections will be out of service. 1080s Will be offline.
 
ALTALINK, RESC 02-Jun-26 08:00 04-Jun-26 18:00 2.42 Days
Continuous
1012L (326s Murray Lake - 516s Forty Mile) Programmed maintenance.
 
ALTALINK 03-Jun-26 09:00 04-Jun-26 16:30 31.5 Hours
Continuous
852s T1 (852s Round Hill) TX Maintenance, Doble and IDD troubleshooting  
ENMAX, ALTALINK 05-Jun-26 08:00 05-Jun-26 18:00 10 Hours
Continuous
693L (42s Sarcee - SS-10), 10.2TR (SS-10), 10B138-693 (SS-10) Power Factor Test - 10PT138-693, 10PT138-Z31. Breaker Trip Circuit Test - 10B138-693  
EPCOR 05-Jun-26 17:00 19-Jun-26 17:00 14 Days
Continuous
EP 805s J2404 (EP 805s Jasper), EP 805s J2403 (EP 805s Jasper), EP 805s J2408 (EP 805s Jasper), 805s C1 (805s Jasper), 1044L (EP 805s Jasper - 816s Petrolia) 1044L/Jasper: J2403 Replacement LCR  
SUNCOR 06-Jun-26 08:00 09-Jun-26 20:00 3.5 Days
Continuous
29EDD-1 29EDD1s952 (29EDD-1 Millennium) 29EDD1s952 - Faulty SF6 Sensors - 300677553  
ALTALINK, BCH 07-Jun-26 08:00 07-Jun-26 17:00 9 Hours
Continuous
786L (799s Coleman - BCH Natal) Repairing woodpecker damage on structures 94, 112 and 118
Replacing damaged insulator on structure 121
AB-BC
EPCOR, ALTALINK 08-Jun-26 07:00 14-Jun-26 17:00 6.42 Days
Continuous
657s T3 (657s Summerside), 657s SU2405 (657s Summerside), 657s SU2401 (657s Summerside) Summerside: TX3 Doble and SUAB3/SUDS2/SUDS12 Disconnect Maintenance  
ENMAX 08-Jun-26 08:00 08-Jun-26 12:00 4 Hours
Continuous
162B240-RB132 (SS-162) HV Breaker SF6 Gas Sample  
ATCO 08-Jun-26 09:30 10-Jun-26 17:30 2.33 Days
Continuous
801s 909 (801s Anderson) BREAKER MIN OIL HLR COMPLETE TESTING  
ATCO 08-Jun-26 10:00 09-Jun-26 16:00 30 Hours
Continuous
849s 901 (849s Joslyn Creek) breaker maintenance, PRC-005 trip coil testing  
ENMAX 08-Jun-26 12:00 08-Jun-26 16:00 4 Hours
Continuous
162B240-RB135 (SS-162) HV Breaker SF6 Gas Sample  
ALTALINK 08-Jun-26 14:00 11-Jun-26 16:00 3.08 Days
Continuous
17s 85 (17s Benalto), 17s T2 (17s Benalto) 17s85 CT Replacement  
ALTALINK, ATCO 08-Jun-26 16:30 29-Jun-26 18:30 21.08 Days
Continuous
87s 1252 (87s Gaetz), 87s 1652 (87s Gaetz), 87s T2 (87s Gaetz), 87s 240kV East Bus (87s Gaetz), 87s 1552 (87s Gaetz), 87s 1952 (87s Gaetz), 962L (87s Gaetz - 972s Tinchebray), 986L (87s Gaetz - 972s Tinchebray) Completing all telecom work & protection testing with ATCO  
ENMAX 09-Jun-26 08:00 09-Jun-26 12:00 4 Hours
Continuous
162B240-RB136 (SS-162) HV Breaker SF6 Gas Sample  
ALTALINK 09-Jun-26 09:15 09-Jun-26 12:30 3.25 Hours
Continuous
852s 152 (852s Round Hill) Breaker maintenance and first trip  
ALTALINK 09-Jun-26 13:15 09-Jun-26 16:30 3.25 Hours
Continuous
852s 252 (852s Round Hill) Breaker maintenance, heater replacement & first trip  
SUNCOR 10-Jun-26 08:00 13-Jun-26 20:00 3.5 Days
Continuous
29EDD-1 29EDD1s852 (29EDD-1 Millennium) 29EDD1S852 Replace Densimeter  
ALTALINK 10-Jun-26 09:00 10-Jun-26 16:00 7 Hours
Continuous
32s 22 (32s Barrier) 32s22 LTB PRC5 minor maintenance.  
BCH 10-Jun-26 09:00 19-Jun-26 17:00 9.33 Days
Continuous
2L294 (BCH A. A. Lambert - BCH Cranbrook), T3 (BCH Cranbrook), T7 (BCH Cranbrook) insulator replacement AB-BC
ATCO 10-Jun-26 10:00 11-Jun-26 16:00 30 Hours
Continuous
849s 904 (849s Joslyn Creek) breaker maintenance, PRC-005 trip coil testing  
ALTALINK 10-Jun-26 23:30 11-Jun-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 11-Jun-26 03:30 11-Jun-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ALTALINK 11-Jun-26 10:00 11-Jun-26 12:00 2 Hours
Continuous
37s 88 (37s North Calder) Breaker fail trip testing  
ALTALINK 11-Jun-26 10:00 12-Jun-26 07:00 21 Hours
Continuous
534s 138kV Bus 1 (534s Eckville), 757L (17s Benalto - 758L tap), 757L (297s Rimbey - 758L tap), 297s 757 (297s Rimbey), 297s T1 (297s Rimbey), 297s T2 (297s Rimbey), 534s 758 (534s Eckville), 534s T1 (534s Eckville), 297s 138kV Bus 1 (297s Rimbey), 17s 757N (17s Benalto), 297s 138kV Bus 2 (297s Rimbey) 757L199 Replace crossarm and insulators.
17s Dead end insulator replacement. Rising Edge Jeremy Lesoway.
 
ALTALINK 11-Jun-26 13:00 11-Jun-26 15:00 2 Hours
Continuous
37s 81 (37s North Calder) Breaker fail trip testing  
SUNCOR 14-Jun-26 08:00 17-Jun-26 20:00 3.5 Days
Continuous
29EDD-1 29EDD1s1052 (29EDD-1 Millennium) 29EDD1S1052 Densimeter Replacement - 300347749  
ATCO 14-Jun-26 09:00 25-Jun-26 17:00 11.33 Days
Continuous
9L62 (87s Gaetz - 972s Tinchebray) Work on parallel line 9L86  
EPCOR 15-Jun-26 07:00 19-Jun-26 17:00 4.42 Days
Continuous
987s GT2 (987s Clover Bar) Cloverbar:  
EPCOR, ALTALINK 15-Jun-26 07:00 19-Jun-26 17:00 4.42 Days
Continuous
1058L (657s Summerside - EP 803s Lambton), EP 803s L2404 (EP 803s Lambton), EP 803s L2403 (EP 803s Lambton) 1058L: Aerial Washing Program  
ALTALINK 15-Jun-26 07:30 18-Jun-26 18:00 3.44 Days
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) South Lines Crew will be doing component replacement on 1325L (STR 501-542) HVDC Maint.  
ALTALINK 15-Jun-26 08:00 19-Jun-26 16:00 4.33 Days
Continuous
266s 252 (266s SC1) 2665sFSC2 Unbalance Alarm, Series cap door bolts, annual maintenance.  
ALTALINK, EPCOR 15-Jun-26 09:00 15-Jun-26 16:00 7 Hours
Continuous
930L (37s North Calder - Poundmaker), 37s 76 (37s North Calder), 37s 81 (37s North Calder), 37s 72 (37s North Calder) 930L MOD (37s72) supervisory cutovers and function testing  
ATCO 15-Jun-26 09:00 18-Jun-26 16:00 3.29 Days
Continuous
7L03 (731s Elmworth - 7L09 tap) TCM pole changes from Test and treat.  
ATCO, CNRL 15-Jun-26 09:00 29-Jun-26 10:00 14.04 Days
Continuous
859s 701TD (859s Primrose), 859s 701 (859s Primrose), 859s 704 (859s Primrose), 859s 701T (859s Primrose) maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 19-Jun-26 17:00 4.31 Days
Continuous
915L (38s East Edmonton - 987s Clover Bar), 987s C2403 (987s Clover Bar), 987s C2405 (987s Clover Bar) 915L/Cloverbar: CT/CVT/SA Doble and CDS35/CDS36/CDS7 Disconnect Maintenance and Relay Maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 19-Jun-26 17:00 4.31 Days
Continuous
915L (38s East Edmonton - 987s Clover Bar) 915L/Cloverbar: CT/CVT/SA Doble and CDS35/CDS36/CDS7 Disconnect Maintenance and Relay Maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 20-Jun-26 17:00 5.31 Days
Continuous
1139L (367s Harry Smith - EP Riverview), RW2405 (EP Riverview), RW2403 (EP Riverview) Riverview: 1139L Zone Doble and RWDS6/RWDS9/RWSA12 Disconnect Maintenance and RW2403/RW2405 (SF6) Breaker Maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 20-Jun-26 17:00 5.31 Days
Continuous
1139L (367s Harry Smith - EP Riverview) Riverview: 1139L Zone Doble and RWDS6/RWDS9/RWSA12 Disconnect Maintenance and RW2403/RW2405 (SF6) Breaker Maintenance  
ATCO 15-Jun-26 10:00 15-Jun-26 11:59 119 Mins
Continuous
849s 902 (849s Joslyn Creek) PRC-005 trip coil testing  
ATCO 15-Jun-26 10:00 17-Jun-26 12:00 2.08 Days
Continuous
2029s ACF12 (2029s Heathfield), 2029s 1219 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF12
PRC-005 - TRIP COIL TESTING - BREAKER 1219 @ 2029S
 
ALTALINK 15-Jun-26 11:30 19-Jun-26 16:30 4.21 Days
Continuous
163s 1752 (163s Amoco Empress), 163s Protection & Control (163s Amoco Empress), 163s 1552 (163s Amoco Empress), 1002L (163s Amoco Empress - 275s Jenner) Replace 163s1752 Breaker CT at 163s Amoco  
ATCO 15-Jun-26 12:00 15-Jun-26 13:59 119 Mins
Continuous
849s 903 (849s Joslyn Creek) PRC-005 trip coil testing  
ATCO 15-Jun-26 14:00 15-Jun-26 15:59 119 Mins
Continuous
849s 905 (849s Joslyn Creek) PRC-005 trip coil testing  
ATCO 16-Jun-26 09:00 25-Jun-26 17:00 9.33 Days
Continuous
972s 240kV Bus 900BS2 (972s Tinchebray) Connect new 9L86 to 972S and prepare to energize.
String Conductors/OPGW 9L86 from Str #3 to substation A-frame deadends and connect to 9L86D1, coordinate with AML conductor jumpers and OPGW termination at the TFO boundary 9L86 Str 409
Complete protection commissioning
 
ATCO 16-Jun-26 10:00 16-Jun-26 11:59 119 Mins
Continuous
849s 906 (849s Joslyn Creek) PRC-005 trip coil testing  
ATCO 16-Jun-26 12:00 16-Jun-26 13:59 119 Mins
Continuous
849s 907 (849s Joslyn Creek) PRC-005 trip coil testing  
EPCOR 17-Jun-26 07:00 24-Jun-26 17:00 7.42 Days
Continuous
987s GT3 (987s Clover Bar) maintenance  
ATCO 17-Jun-26 13:00 19-Jun-26 17:30 2.19 Days
Continuous
2029s ACF14 (2029s Heathfield), 2029s 1221 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF12
PRC-005 - TRIP COIL TESTING - BREAKER 1219 @ 2029S
 
ENMAX, ALTALINK 19-Jun-26 08:00 19-Jun-26 16:00 8 Hours
Continuous
693L (42s Sarcee - SS-10), 10B138-693 (SS-10) HV Breaker SF6 Gas Sample - 10B138-693  
EPCOR 22-Jun-26 07:00 25-Jun-26 17:00 3.42 Days
Continuous
987s GT1 (987s Clover Bar) maintenance  
SUNCOR 22-Jun-26 08:00 28-Jun-26 20:00 6.5 Days
Continuous
29PL9-17 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT419 / 29PL9-17 SYSTEM;PM 5y,10y; 29PL9-17 Powerline & OHSW repairs
 
EPCOR, ALTALINK 22-Jun-26 09:00 28-Jun-26 17:00 6.33 Days
Continuous
52s T1 (52s East Industrial), 1059AL (52s East Industrial - 1059L tap), 1059L (EP 803s Lambton - 1059AL tap), EP 803s L2401 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton) East Industrial: Apparatus- TX1 Doble, and Aerial- Jumper Conductor Repair and Insulator Washing  
ALTALINK, EPCOR 22-Jun-26 09:30 27-Jun-26 17:00 5.31 Days
Continuous
921L (71s Lamoureux - 987s Clover Bar), 987s C2404 (987s Clover Bar), 987s C2406 (987s Clover Bar) 921L/Cloverbar: CT/CVT/SA Doble and CDS9/CDS14/CDS17 Disconnect Maintenance and C2404 (Min Oil) Breaker Maintenance and C2401 Relay Maintenance  
ALTALINK, EPCOR 22-Jun-26 09:30 27-Jun-26 17:00 5.31 Days
Continuous
921L (71s Lamoureux - 987s Clover Bar) 921L/Cloverbar: CT/CVT/SA Doble and CDS9/CDS14/CDS17 Disconnect Maintenance and C2404 (Min Oil) Breaker Maintenance and C2401 Relay Maintenance  
ALTALINK, EPCOR 22-Jun-26 09:30 28-Jun-26 17:00 6.31 Days
Continuous
1059L (38s East Edmonton - 1059AL tap), 1059L (EP 803s Lambton - 1059AL tap) East Industrial: Apparatus- TX1 Doble, and Aerial- Jumper Conductor Repair and Insulator Washing  
ATCO 22-Jun-26 10:00 24-Jun-26 12:00 2.08 Days
Continuous
2029s ACF11 (2029s Heathfield), 2029s 1218 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF11
PRC-005 - TRIP COIL TESTING - BREAKER 1218 @ 2029S
 
ATCO 24-Jun-26 13:00 26-Jun-26 17:30 2.19 Days
Continuous
2029s ACF21 (2029s Heathfield), 2029s 1222 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF21
PRC-005 - TRIP COIL TESTING - BREAKER 1222 @ 2029S
 
SUNCOR 29-Jun-26 08:00 02-Jul-26 19:00 3.46 Days
Continuous
29PL9-16 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT418/29PL9-16 SYSTEM;PM 5y,10y
 
ATCO 29-Jun-26 09:00 29-Jun-26 17:30 8.5 Hours
Continuous
2075s ACF24 (2075s Newell), 2075S 933 (2075s Newell) PRC-005 - TRIP COIL TESTING - BREAKER 933 @ 2075S
FILTER BANK AC MAINTENANCE @ NEWELL 2075S ACF24
 
ATCO 29-Jun-26 10:00 30-Jun-26 17:30 31.5 Hours
Continuous
2029s ACF13 (2029s Heathfield), 2029s 1220 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF13
PRC-005 - TRIP COIL TESTING - BREAKER 1220 @ 2029S
 
ALTALINK 29-Jun-26 13:00 30-Jun-26 17:00 28 Hours
Continuous
132s 55 (132s Ware Junction) 132s55 Minor Maint. First Trip.  
ATCO 30-Jun-26 09:00 30-Jun-26 17:30 8.5 Hours
Continuous
2075s ACF23 (2075s Newell), 2075S 932 (2075s Newell) PRC-005 - TRIP COIL TESTING - BREAKER 932 @ 2075S
FILTER BANK AC MAINTENANCE @ NEWELL 2075S ACF23
 
ALTALINK 30-Jun-26 10:00 30-Jun-26 16:00 6 Hours
Continuous
63s T2 (63s Red Deer), 63s 25 (63s Red Deer) PRC5 maintenance and first trip  
ATCO 30-Jun-26 10:00 30-Jun-26 16:00 6 Hours
Continuous
856s 902T (856s Kinosis), 856s 505R (856s Kinosis) PRC-005 sudden pressure relay trip testing  
ATCO 02-Jul-26 09:00 03-Jul-26 17:30 1.35 Days
Continuous
2075s ACF22 (2075s Newell), 2075S 931 (2075s Newell) PRC-005 - TRIP COIL TESTING - BREAKER 931 @ 2075S
FILTER BANK AC MAINTENANCE @ NEWELL 2075S ACF22
 
ATCO 02-Jul-26 10:00 03-Jul-26 17:30 31.5 Hours
Continuous
2029s ACF23 (2029s Heathfield), 2029s 1224 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF23
PRC-005 - TRIP COIL TESTING - BREAKER 1224 @ 2029S
 
ATCO, SUNCOR 03-Jul-26 08:00 09-Jul-26 20:00 6.5 Days
Continuous
29PL9-1 (29EDD-1 Millennium - 848s Ruth Lake), 29EDD-1 29EDD1s452 (29EDD-1 Millennium) 29EDD1;29CVT-3 SYSTEM;PM 5y,10y; 29EDD1;29EDD1S452 MAINT&TEST;PM 10y; 29EDD1;29CVT-3 SYSTEM;PM 5y,10y; 29PL9-1 Str#5 vibration damper
 
EPCOR 06-Jul-26 07:00 12-Jul-26 17:00 6.42 Days
Continuous
987s T2 (987s Clover Bar), 987s CC721 (987s Clover Bar), 987s C2406 (987s Clover Bar), 987s C2410 (987s Clover Bar) Cloverbar: TX2 Doble and CDS1/CDS31/CDS33/CDS43 Disconnect Maintenance and Measurements w/Engineering  
ATCO, GREENGATEP 06-Jul-26 09:00 09-Jul-26 17:00 3.33 Days
Continuous
9L59 (801s Anderson - 9LA59 tap), 9L59 (972s Tinchebray - 9LA59 tap) Connect new 907B to 900BS1
 
ATCO 06-Jul-26 09:00 10-Jul-26 17:30 4.35 Days
Continuous
2075s ACF21 (2075s Newell), 2075S 930 (2075s Newell) SVC NEWELL MAINTENANCE - SVC2 @ 2075S
SEMI-ANNUAL SVC VALVE COOLING MAINTENANCE @ NEWELL 2075S SVC2
PRC-005 - TRIP COIL TESTING - BREAKER 930 @ 2075S
SVC2 Blocking Switch Installs
SVC2 VESDA Replacement
SVC2 Annual Fire System Inspection
 
ATCO 06-Jul-26 09:30 09-Jul-26 13:00 3.15 Days
Continuous
856s 903T (856s Kinosis) transformer maintenance
PRC-005 trip coil testing on 903 and 906 during this switching
 
ATCO 06-Jul-26 10:00 07-Jul-26 16:00 30 Hours
Continuous
825s 901 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 06-Jul-26 10:00 10-Jul-26 17:30 4.31 Days
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
 
ATCO, ALTALINK 08-Jul-26 07:00 08-Jul-26 18:00 11 Hours
Continuous
9L912 (63s Red Deer - 766s Nevis), 766s 902 (766s Nevis) AltaLink Scope: Replacing insulators on structure 36
Switching line out of service for AltaLink to perform maintenance
 
ALTALINK, ATCO 08-Jul-26 08:00 08-Jul-26 17:00 9 Hours
Continuous
63s 852 (63s Red Deer), 63s 952 (63s Red Deer), 912L (63s Red Deer - 766s Nevis) Replacing insulators on structure 36  
ATCO 08-Jul-26 10:00 09-Jul-26 16:00 30 Hours
Continuous
825s 902 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 09-Jul-26 13:01 09-Jul-26 15:00 119 Mins
Continuous
856s 901 (856s Kinosis) PRC-005 trip coil testing  
ENMAX, ALTALINK 10-Jul-26 08:00 10-Jul-26 16:00 8 Hours
Continuous
37.82L (74s Janet - SS-37) Shield Wire Replacement.  
ALTALINK, ENMAX 10-Jul-26 08:00 10-Jul-26 17:00 9 Hours
Continuous
74s 37.82W (74s Janet), 37.82L (74s Janet - SS-37) Enmax Shield Wire Replacement.  
ATCO, SUNCOR 10-Jul-26 08:00 16-Jul-26 20:00 6.5 Days
Continuous
29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake), 29EDD-1 29EDD1s152 (29EDD-1 Millennium) 29EDD1;29CVT-1 SYSTEM;PM 5y,10y  
EPCOR 13-Jul-26 07:00 19-Jul-26 17:00 6.42 Days
Continuous
EP 803s L2401 (EP 803s Lambton) Lambton: L2401 (Min Oil) Breaker Maintenance and CT Doble  
EPCOR 13-Jul-26 07:00 21-Aug-26 17:00 39.42 Days
Continuous
EP 805s J2401 (EP 805s Jasper) Jasper: J2401 Replacement LCR  
ATCO 13-Jul-26 09:00 24-Jul-26 17:30 11.35 Days
Continuous
2075S 927 (2075s Newell), 2075S 928 (2075s Newell), 2075S 929 (2075s Newell), 2075S 934 (2075s Newell), 2075s ACF11 (2075s Newell), 2075s ACF12 (2075s Newell), 2075s ACF13 (2075s Newell), 2075s ACF14 (2075s Newell) SVC NEWELL MAINTENANCE - SVC1 @ 2075S
SEMI-ANNUAL SVC VALVE COOLING MAINTENANCE @ NEWELL 2075S SVC1
**PLEASE ADD IN 2075S ACF1**
 
ATCO 13-Jul-26 10:00 14-Jul-26 16:00 30 Hours
Continuous
825s 903 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 13-Jul-26 10:00 14-Jul-26 16:00 30 Hours
Continuous
856s 902 (856s Kinosis) PRC-005 trip coil testing, BREAKER MAINTENANCE  
ALTALINK 14-Jul-26 09:30 23-Jul-26 11:00 9.06 Days
Continuous
163s T5 (163s Amoco Empress) 163sT5 maintenance and oil leaks.  
ENMAX, ALTALINK 15-Jul-26 08:00 15-Jul-26 16:00 8 Hours
Continuous
1064L (74s Janet - 102s Langdon) Shield Wire Replacement.  
ENMAX, ALTALINK 15-Jul-26 08:00 15-Jul-26 16:00 8 Hours
Continuous
1065L (74s Janet - 102s Langdon) Shield Wire Replacement.  
SUNCOR 15-Jul-26 08:00 25-Jul-26 20:00 10.5 Days
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
 
ALTALINK 15-Jul-26 10:00 15-Jul-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ATCO 15-Jul-26 10:00 16-Jul-26 16:00 30 Hours
Continuous
825s 904 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 15-Jul-26 10:00 16-Jul-26 16:00 30 Hours
Continuous
856s 904 (856s Kinosis) PRC-005 trip coil testing, BREAKER MAINTENANCE  
ALTALINK 16-Jul-26 10:00 16-Jul-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ATCO, SUNCOR 17-Jul-26 08:00 23-Jul-26 20:00 6.5 Days
Continuous
6L32 (29EDD-1 Millennium - 737s ATC Horseshoe), 29EDD-1 29EDD1S28 (29EDD-1 Millennium), 29EDD-1 29PS-197 (29EDD-1 Millennium) 29EDD1;29CVT-6 SYSTEM;5y,10y; 29EDD1s28 Alignment Issues; 29PS-197 Paddle Rotation
 
EPCOR 20-Jul-26 07:00 26-Jul-26 17:00 6.42 Days
Continuous
EP 803s L2402 (EP 803s Lambton) Lambton: L2402 (Min Oil) Breaker Maintenance and CT Doble  
EPCOR 20-Jul-26 07:00 02-Aug-26 17:00 13.42 Days
Continuous
987s CCP7213 (987s Clover Bar), 987s CCP7214 (987s Clover Bar), 987s C2401 (987s Clover Bar), 987s C2403 (987s Clover Bar), 987s T1 (987s Clover Bar) Cloverbar: C2401/C2403 Breaker Maintenance and CT Doble and CDS19 LCR and C2401 Relay Maintenance  
ALTALINK, TRANSALTA 20-Jul-26 08:00 23-Jul-26 17:00 3.38 Days
Continuous
179s 733 (179s Gleichen), 428s 733X (428s Namaka), 733L (179s Gleichen - 428s Namaka) Interphase spacers str: 181, 193, 195, 196
Repair conductor with sleeve or preform splice: 181,193, 195, 196
Str change: 211 (foundation in concrete)
arm/insulator change str: 161, 163, 165
"
 
ALTALINK 20-Jul-26 09:30 20-Jul-26 15:00 5.5 Hours
Continuous
138s 2552 (138s Windy Flats), 603L (138s Windy Flats - 243s Soderglen) Job Scope: We need to complete maintenance on 243s138DS1  
ATCO 20-Jul-26 10:00 21-Jul-26 16:00 30 Hours
Continuous
825s 905 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 20-Jul-26 10:00 22-Jul-26 12:00 2.08 Days
Continuous
804s 702 (804s Wintering Hills), 7L85 (804s Wintering Hills - 7LA85 tap) BREAKER SF6 GL312 TESTING - 702 @ 804S  
ATCO 20-Jul-26 10:00 24-Jul-26 16:00 4.25 Days
Continuous
977s 901T (977s Salt Creek), 7L135 (820s Hangingstone - 977s Salt Creek) TRANSFORMER AND TAP CHANGER MAINTENANCE  
ALTALINK 20-Jul-26 14:00 31-Jul-26 17:00 11.13 Days
Continuous
63s 452 (63s Red Deer), 1083L (63s Red Deer - 288s Wolf Creek) 63s452 Breaker Replacement to SF6 breaker.  
ATCO 21-Jul-26 08:00 21-Jul-26 16:00 8 Hours
Continuous
7L85 (804s Wintering Hills - 7LA85 tap) Interphase spacer install, Deficiency repairs & insulator replacement between Wintering Hills and Badlands  
ATCO 21-Jul-26 08:00 22-Jul-26 17:00 1.38 Days
Continuous
7L65 (709s Vegreville - 7LA65 tap), 7L65 (710s Vermilion - 7LA65 tap), 7LA65 (708s Grizzly Bear - 7L65 tap) Switch Repairs, 7LA65D1  
ATCO, OWF2 22-Jul-26 12:00 24-Jul-26 17:30 2.23 Days
Continuous
804s 703 (804s Wintering Hills), 7L153 (609s Wheatland - 804s Wintering Hills) BREAKER SF6 GL312 TESTING - 703 @ 804S  
ATCO 23-Jul-26 08:00 23-Jul-26 15:00 7 Hours
Continuous
7L85 (803s ATC Bullpound - 7LA85 tap) Interphase spacer install, Deficiency repairs & insulator replacement between Badlands and Bullpound  
SUNCOR 24-Jul-26 08:00 06-Aug-26 20:00 13.5 Days
Continuous
29EDD-34 29PT-341 (29EDD-34), 29EDD-34 29-952-142 (29EDD-34), 29EDD-34 29-952-143 (29EDD-34), 29EDD-34 29-652-10200T (29EDD-34), 29EDD-34 29-652-10301 (29EDD-34), 29EDD-34 29-652-10302 (29EDD-34), 29EDD-34 29-652-10303 (29EDD-34), 29EDD-34 29PS-0375 (29EDD-34), 29EDD-34 29PS-0380 (29EDD-34), 29EDD-34 29PS-0381 (29EDD-34), 29EDD-34 29PS-0383 (29EDD-34), 29EDD-34 29PS-609 (29EDD-34) 10 year PM on 29EDD34;29PT-341 system and 5 year, 10 year PM on 29EDD34;29PP-103 system
 
SUNCOR 25-Jul-26 08:00 31-Jul-26 20:00 6.5 Days
Continuous
29PL9-3 (29EDD-1 Millennium - 29EDD-3), 29EDD-3 29PT-6 (29EDD-3) 29EDD1;29CVT-4 SYSTEM;PM 5y,10y;
 
ALTALINK, TRANSALTA 27-Jul-26 08:00 30-Jul-26 17:00 3.38 Days
Continuous
179s 733 (179s Gleichen), 428s 733X (428s Namaka), 733L (179s Gleichen - 428s Namaka) Interphase spacers str: 181, 193, 195, 196
Repair conductor with sleeve or preform splice: 181,193, 195, 196
Str change: 211 (foundation in concrete)
arm/insulator change str: 161, 163, 165
"
 
ALTALINK, EPCOR 27-Jul-26 08:30 31-Jul-26 18:00 4.4 Days
Continuous
310p 1352 (310p Sundance), 310p 1452 (310p Sundance), 909L (310p Sundance - 665s Dome) 909LW/Dome: CVT/SA Doble and DDS6/DDS7/DDS14 Disconnect Maintenance and 909LW Relay Maintenance  
ALTALINK, EPCOR 27-Jul-26 09:30 31-Jul-26 17:00 4.31 Days
Continuous
909L (310p Sundance - 665s Dome), 665s D2403 (665s Dome) 909LW/Dome: CVT/SA Doble and DDS6/DDS7/DDS14 Disconnect Maintenance and 909LW Relay Maintenance  
ATCO 27-Jul-26 10:00 29-Jul-26 16:00 2.25 Days
Continuous
848s 905 (848s Ruth Lake) BREAKER MAINTENANCE  
ATCO 27-Jul-26 10:00 31-Jul-26 17:30 4.31 Days
Continuous
801s 901T (801s Anderson), 801s 704 (801s Anderson), 7L85 (801s Anderson - ATC 803s Bullpound) PRC-005 - SPR TESTING - TRANSFORMER 901T @ 801S
Replace X3 Bushing on 901T at 801s Anderson
TRANSFORMER CLASS1 MAJOR TESTING - 901T @ 801S
TRANSFORMER CLASS1 TAP CHANGER - 901T @ 801S
BREAKER MIN OIL HLR PARTIAL TESTING - 704 @ 801S
 
ATCO 28-Jul-26 08:00 29-Jul-26 16:00 1.33 Days
Continuous
7L85 (801s Anderson - ATC 803s Bullpound) Interphase spacer install, Deficiency repairs & cross arm replacement between Bullpound and Anderson  
ATCO 28-Jul-26 10:00 29-Jul-26 17:00 31 Hours
Continuous
789s 701 (789s Keg River), 7L64 (779s Chinchaga River - 789s Keg River) PRC Trip Coil Testing. 789s 7L62D2 will be closed for the outage duration.  
ALTALINK 29-Jul-26 23:30 30-Jul-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 30-Jul-26 03:30 30-Jul-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ATCO 30-Jul-26 10:00 31-Jul-26 17:00 31 Hours
Continuous
789s 703 (789s Keg River), 7L59 (789s Keg River - 7L59 tap) PRC Trip Coil Testing  
ENMAX, ALTALINK 04-Aug-26 08:00 21-Aug-26 16:00 17.33 Days
Continuous
24.83L (74s Janet - SS-24) Wood pole installation  
ALTALINK, ENMAX 04-Aug-26 08:00 21-Aug-26 16:00 17.33 Days
Continuous
74s 24.83X (74s Janet), 24.83L (74s Janet - SS-24) Enmax Wood pole installation  
ALTALINK, TRANSALTA 04-Aug-26 09:00 06-Aug-26 17:00 2.33 Days
Continuous
179s 733 (179s Gleichen), 428s 733X (428s Namaka), 733L (179s Gleichen - 428s Namaka) 733Lstr. 161-211 Crossarm work. Maintenance/repairs.  
ATCO 04-Aug-26 10:00 06-Aug-26 16:00 2.25 Days
Continuous
848s 906 (848s Ruth Lake) BREAKER MAINTENANCE  
ALTALINK 06-Aug-26 07:00 06-Aug-26 18:00 11 Hours
Daily
237s 2352 (237s Foothills), 237s 2652 (237s Foothills), 237s T2 (237s Foothills), 237s 240kV Bus 2 (237s Foothills) Install bus support piles for new 240kV Bay.  
ALTALINK 07-Aug-26 07:00 07-Aug-26 18:00 11 Hours
Daily
237s 2152 (237s Foothills), 237s 2452 (237s Foothills), 237s T1 (237s Foothills), 237s 240kV Bus 1 (237s Foothills) Install bus support piles for new 240kV Bay.  
SUNCOR 07-Aug-26 08:00 20-Aug-26 20:00 13.5 Days
Continuous
29EDD-34 29PT-340 (29EDD-34) 29EDD34;29PT-340 SYSTEM;PM 5y,10y; 29EDD34;29PP-102 SYSTEM;PM 5y,10y
 
EPCOR 10-Aug-26 07:00 16-Aug-26 17:00 6.42 Days
Continuous
665s T3 (665s Dome), 665s D721 (665s Dome), 665s D2404 (665s Dome), S721 (Strathcona) DS26/Dome/Strathcona: Dome TX3 Doble and DAB3/DDS15/DDS16 Disconnect Maintenance and Strathcona DS26/CVT Doble and SDS3 Disconnect Maintenance  
ATCO 10-Aug-26 09:00 13-Aug-26 16:00 3.29 Days
Continuous
969s 701T (969s Lindbergh) total station outage to replace failing HO/XO bushings on transformer, updates to anti-islanding RAS logic and alarming, replace NGR resistor and relay
 
ATCO, ALTALINK 10-Aug-26 09:30 11-Aug-26 17:30 1.33 Days
Continuous
757s 708 (757s Battle River), 7L702 (137s Sedgewick - 757s Battle River) BREAKER SF6 LTB145D1/B TESTING - 708 @ 757S
PRC-005 - TRIP COIL TESTING - BREAKER 708 @ 757S
 
ALTALINK 10-Aug-26 09:30 13-Aug-26 17:00 3.31 Days
Continuous
702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 10-Aug-26 10:00 13-Aug-26 16:30 3.27 Days
Continuous
7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 10-Aug-26 10:00 14-Aug-26 17:30 4.31 Days
Continuous
959s SVC (959s Lanfine) DFR Upgrade / Replacement
SVC Transformer Maintenance
Fire system inspection
Install Blocking Switches
Mechanical Maintenance & Capital
BATTERY CHARGER COMPLETE TESTING @ LANFINE 959S SVC DC MOTOR
 
ATCO 10-Aug-26 13:00 10-Aug-26 14:00 60 Mins
Continuous
951s 1205 (951s Thickwood Hills) PRC-005 Trip Coil testing, SOC ill open and close breaker (tests TC #1), Techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2)  
ALTALINK 10-Aug-26 13:00 13-Aug-26 16:00 3.13 Days
Continuous
368s 612 (368s Burdett), 612L (336s Fincastle - 368s Burdett) 368s612 138kv CT Replacement  
ATCO 10-Aug-26 14:01 10-Aug-26 15:00 59 Mins
Continuous
951s 1206 (951s Thickwood Hills) PRC-005 Trip Coil testing, SOC ill open and close breaker (tests TC #1), Techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2)  
ATCO 10-Aug-26 15:00 10-Aug-26 16:00 60 Mins
Continuous
951s 1213 (951s Thickwood Hills) PRC-005 Trip Coil testing, SOC will open and close breaker (tests TC #1), Techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2)  
ATCO 11-Aug-26 10:00 11-Aug-26 11:00 60 Mins
Continuous
939s 1206 (939s Livock) PRC-005 Trip Coil testing,  
ATCO 11-Aug-26 11:00 11-Aug-26 12:00 60 Mins
Continuous
939s 1207 (939s Livock) PRC-005 Trip Coil testing, SOC will open and close breaker (tests TC #1), Techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2)  
ATCO 11-Aug-26 13:00 11-Aug-26 14:00 60 Mins
Continuous
939s 1216 (939s Livock) PRC-005 Trip Coil testing, SOC will open and close breaker (tests TC #1), Techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2)  
ATCO 12-Aug-26 09:30 13-Aug-26 17:30 1.33 Days
Continuous
757s 704 (757s Battle River), 757s 704T (757s Battle River) BREAKER SF6 LTB145D1/B TESTING - 704 @ 757S
PRC-005 - TRIP COIL TESTING - BREAKER 704 @ 757S
 
ATCO 12-Aug-26 10:00 14-Aug-26 16:00 2.25 Days
Continuous
848s 907 (848s Ruth Lake) BREAKER MAINTENANCE  
ALTALINK, EPCOR 17-Aug-26 09:30 22-Aug-26 17:00 5.31 Days
Continuous
920L (71s Lamoureux - 557s Castle Downs), 557s CD2405 (557s Castle Downs), 557s CD2404 (557s Castle Downs) 920LE/Castledowns: CT/CVT Doble and Surge Arrestor LCR  
ALTALINK, EPCOR 17-Aug-26 09:30 22-Aug-26 17:00 5.31 Days
Continuous
920L (71s Lamoureux - 557s Castle Downs) 920LE/Castledowns: CT/CVT Doble and Surge Arrestor LCR  
ATCO 17-Aug-26 10:00 20-Aug-26 16:30 3.27 Days
Continuous
7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ALTALINK 17-Aug-26 10:00 20-Aug-26 16:30 3.27 Days
Continuous
702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ALTALINK 17-Aug-26 12:00 20-Aug-26 17:00 3.21 Days
Continuous
245s 777X (245s Seebe), 777L (48s Pocaterra - 245s Seebe) 245s777X 138kV CT testing AB-BC
ALTALINK, ATCO, FMGW 18-Aug-26 08:00 19-Aug-26 17:00 1.38 Days
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  
EPCOR 24-Aug-26 07:00 09-Oct-26 17:00 46.42 Days
Continuous
805s T4 (805s Jasper), EP 805s J2405 (EP 805s Jasper), EP 805s J2406 (EP 805s Jasper) Jasper: J2406/JDS10 Replacement LCR  
ALTALINK, BCH 24-Aug-26 08:00 01-Sep-26 17:00 8.38 Days
Continuous
Path 1 (AIES Islanding), 1201L (520s Bennett - BCH Cranbrook), 5L94 (BCH Cranbrook - 520s Bennett) South Crew will be doing Insulator and guy wire replacements AB-BC
ALTALINK, BCH 24-Aug-26 08:00 01-Sep-26 17:00 8.38 Days
Continuous
48s 887X (48s Pocaterra), 887L (48s Pocaterra - 978s BCH Britt Creek) Opened because 1201L is out of service . AB-BC
ALTALINK, BCH 24-Aug-26 08:00 01-Sep-26 17:00 8.38 Days
Continuous
799s 786W (799s Coleman), 786L (799s Coleman - BCH Natal) Opened because 1201L is out of service. AB-BC
BHE Canada 24-Aug-26 08:00 01-Sep-26 17:00 8.38 Days
Continuous
MATL (120s Picture Butte - Montana) align with 1201L outage AB-MATL
ALTALINK 24-Aug-26 13:00 28-Aug-26 17:00 4.17 Days
Continuous
28s R1 (28s West Brooks) 28sR1 leak category 5, Doble R1
28s44 PRC5 (no first trip)
 
Syncrude 28-Aug-26 08:00 11-Sep-26 16:00 14.33 Days
Continuous
223B (Aurora), 213B (Aurora), 89-216 (Aurora), 89-52 (Aurora), 34B (Aurora), 24B (Aurora), 14B (Aurora), T11 (Aurora), 72 kV Bus 2 (Aurora), 260kV Bus 2 (Aurora) Zone 1 6yr PM  
EPCOR, ALTALINK 31-Aug-26 07:00 13-Sep-26 17:00 13.42 Days
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), 72LS24 (EP 803s Lambton - Strathcona), 72LH8 (EP 803s Lambton - EP Hardisty), H726 (EP Hardisty), S724 (Strathcona) Lambton: LDS14 LCR and L721 Breaker Maintenance (Min Oil) and TX3 Zone Doble and L2405 Breaker Maintenance (SF6) and LDS12 Drive Pipe Repair and TX3 Relay Maintenance  
ATCO 31-Aug-26 09:30 04-Sep-26 17:30 4.33 Days
Continuous
801s 902 (801s Anderson) BREAKER MIN OIL HLR COMPLETE TESTING  
ATCO 31-Aug-26 10:00 03-Sep-26 16:00 3.25 Days
Continuous
826s 902T (826s Marguerite Lake) transformer maintenance  
EPCOR 07-Sep-26 07:00 11-Sep-26 17:00 4.42 Days
Continuous
987s GT2 (987s Clover Bar) Cloverbar:  
ATCO 08-Sep-26 10:00 10-Dec-26 16:00 93.29 Days
Continuous
2015s 902 (2015s Yeo) Remove circuit breaker for use at 2102S Armistead. New breaker to be installed at 2015S Yeo substation once received from manufacturer.  
ALTALINK 08-Sep-26 13:00 17-Sep-26 16:00 9.13 Days
Continuous
370s 2152 (370s North Lethbridge), 370s T3 (370s North Lethbridge) 370sT3 Leak repair, major TC maint. PRC5  
ALTALINK 08-Sep-26 23:00 09-Sep-26 07:00 8 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ALTALINK 09-Sep-26 07:00 10-Sep-26 07:00 24 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 10-Sep-26 19:00 15-Sep-26 12:00 4.71 Days
Continuous
1141L (1172s Laramide - 237s Foothills) End to end testing with Laramide 1172s  
EPCOR 14-Sep-26 07:00 21-Sep-26 17:00 7.42 Days
Continuous
987s GT3 (987s Clover Bar) Cloverbar:  
ALTALINK, EPCOR 14-Sep-26 09:30 17-Sep-26 17:00 3.31 Days
Continuous
920L (37s North Calder - 557s Castle Downs), 557s CD2401 (557s Castle Downs), 557s CD2403 (557s Castle Downs) 920LW/Castledowns: Surge Arrestor LCR  
ALTALINK, EPCOR 14-Sep-26 09:30 17-Sep-26 17:00 3.31 Days
Continuous
920L (37s North Calder - 557s Castle Downs) 920LW/Castledowns: Surge Arrestor LCR  
ATCO, ALTALINK 14-Sep-26 10:00 28-Sep-26 17:30 14.31 Days
Continuous
840s 901T (840s McNeill Station), 830L (562s Cypress - 840s McNeill Station), 840s 701 (840s McNeill Station), 840s 901 (840s McNeill Station) Replace 901T bushings
901T Oil Leak Absorption Repairs At 840s McNeill
AB-SK
ALTALINK, Lethbridge 15-Sep-26 09:00 24-Sep-26 17:30 9.35 Days
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  
ALTALINK 16-Sep-26 23:30 17-Sep-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 17-Sep-26 03:30 17-Sep-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ATCO 21-Sep-26 10:00 24-Sep-26 16:00 3.25 Days
Continuous
888s 906 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
EPCOR 22-Sep-26 07:00 25-Sep-26 17:00 3.42 Days
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 25-Sep-26 10:00 28-Sep-26 16:00 3.25 Days
Continuous
888s 905 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
ALTALINK, TRANSALTA, Lethbridge 28-Sep-26 09:00 28-Sep-26 15:00 6 Hours
Continuous
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  
Lethbridge 28-Sep-26 09:00 15-Oct-26 17:00 17.33 Days
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, Lethbridge 28-Sep-26 14:05 15-Oct-26 18:05 17.17 Days
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  
EPCOR 05-Oct-26 07:00 18-Oct-26 17:00 13.42 Days
Continuous
CV5 (EP 511s Victoria - 557s Castle Downs) CV5: Manhole Inspections and Maintenance  
ALTALINK 05-Oct-26 08:30 28-Nov-26 06:30 53.96 Days
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ATCO 05-Oct-26 10:00 08-Oct-26 16:00 3.25 Days
Continuous
9L74 (888s Dover - 960s Birchwood Creek) 21B/9L74 relay three terminal line testing  
ATCO, ALTALINK 07-Oct-26 08:00 07-Oct-26 17:00 9 Hours
Continuous
760L (760AL tap - 7LA760 tap) install interphase spacers  
ATCO 12-Oct-26 10:00 15-Oct-26 16:00 3.25 Days
Continuous
888s 906 (888s Dover) 21A/9L74 relay replacement. Cutover breaker and CT to new protection  
EPCOR 13-Oct-26 07:00 04-Dec-26 17:00 52.46 Days
Continuous
805s T3 (805s Jasper), EP 805s J2404 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: J2404/JAB3/JDS9 Replacement LCR  
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 3.25 Days
Continuous
888s 905 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
ALTALINK 19-Oct-26 07:00 20-Oct-26 18:00 1.46 Days
Continuous
237s 2352 (237s Foothills), 237s 2652 (237s Foothills), 237s T2 (237s Foothills), 237s 240kV Bus 2 (237s Foothills) Closing Open Point 'C'  
EPCOR 19-Oct-26 07:00 30-Oct-26 17:00 11.42 Days
Continuous
814s T1 (814s Bellamy), BR721 (Rossdale), 814s B2401 (814s Bellamy), 814s B2407 (814s Bellamy) Bellamy: TX1 LTC Monitor Install  
ALTALINK, EPCOR 19-Oct-26 09:30 25-Oct-26 17:00 6.31 Days
Continuous
908L (89s Ellerslie - 816s Petrolia), 816s P2401 (816s Petrolia), 816s P2406 (816s Petrolia) Petrolia: 908LE Surge Arrestor and CVT LCR  
ALTALINK, EPCOR 19-Oct-26 09:30 25-Oct-26 17:00 6.31 Days
Continuous
908L (89s Ellerslie - 816s Petrolia) Petrolia: 908LE Surge Arrestor and CVT LCR  
ALTALINK 21-Oct-26 08:00 22-Oct-26 17:00 1.38 Days
Continuous
237s 2152 (237s Foothills), 237s 2452 (237s Foothills), 237s T1 (237s Foothills), 237s 240kV Bus 1 (237s Foothills), 1141L (1172s Laramide - 237s Foothills) Closing Open Points 'A' & 'B'  
ALTALINK, EPCOR 26-Oct-26 07:00 30-Oct-26 17:00 4.42 Days
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  
ALTALINK, EPCOR 26-Oct-26 07:30 30-Oct-26 17:00 4.4 Days
Continuous
89s 1052 (89s Ellerslie), 89s 1152 (89s Ellerslie), 909L (89s Ellerslie - 665s Dome) 909LE/Dome: Dome CVT LCR and 909LE Metering Upgrade  
ENMAX, ALTALINK 26-Oct-26 08:00 04-Nov-26 16:00 9.38 Days
Continuous
24.83L (74s Janet - SS-24) Steel pole installation  
ENMAX, ALTALINK 26-Oct-26 08:00 04-Nov-26 16:00 9.38 Days
Continuous
24.83L (74s Janet - SS-24), 74s 24.83X (74s Janet) Enmax Steel pole installation  
ATCO 26-Oct-26 10:00 29-Oct-26 16:00 3.25 Days
Continuous
9L74 (888s Dover - 960s Birchwood Creek) 21B/9L74 relay three terminal line testing  
ATCO, ALTALINK 26-Oct-26 10:00 02-Nov-26 16:00 7.29 Days
Continuous
7L230 (69s North Barrhead - 888AL tap), 7L230 (743s Sarah Lake - 888AL tap) Replace 7L230D1 disconnect switch  
ALTALINK 28-Oct-26 10:00 28-Oct-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 29-Oct-26 10:00 29-Oct-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ATCO 30-Oct-26 10:00 02-Nov-26 17:00 3.33 Days
Continuous
7L238 (959s Lanfine - 601s Bufallo Bird), 959s 708 (959s Lanfine), 959s 707 (959s Lanfine) Cutover CT/PT ccts, Commission new RAS A-B/7L238, end-to-end testing with 601S Buffalo Bird  
EPCOR 02-Nov-26 07:00 13-Nov-26 17:00 11.42 Days
Continuous
814s T2 (814s Bellamy), BR722 (Rossdale), 814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy) Bellamy: TX2 LTC Monitor Install  
ALTALINK 05-Nov-26 03:30 05-Nov-26 06:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
EPCOR 09-Nov-26 07:00 11-Dec-26 17:00 32.42 Days
Continuous
52s T2 (52s East Industrial), 52s E2402 (52s East Industrial) East Industrial: TX2 Bushing Replacement  
EPCOR 09-Nov-26 07:00 11-Dec-26 17:00 32.42 Days
Continuous
PM2405 (Poundmaker) Poundmaker: P2405 Breaker Replacement  
ATCO 09-Nov-26 10:00 12-Nov-26 17:00 3.29 Days
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 13-Nov-26 10:00 14-Nov-26 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) Cutover MOD status, Commission inputs to RAS 204 A/B  
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 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 919 status to RAS 204 A/B  
ALTALINK 16-Dec-26 10:00 16-Dec-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
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 39.42 Days
Continuous
EP 805s J2405 (EP 805s Jasper) Jasper: J2405 Replacement LCR  
EPCOR 16-Feb-27 07:00 30-Mar-27 17:00 42.38 Days
Continuous
EP 805s J2407 (EP 805s Jasper) Jasper: J2407 Replacement LCR  
ALTALINK, EPCOR 19-Feb-27 07:00 05-Mar-27 17:00 14.42 Days
Continuous
1045L (EP 805s Jasper - 1045AL tap), EP 805s J2406 (EP 805s Jasper), EP 805s J2407 (EP 805s Jasper) 1045L/Jasper: J2407 Replacement LCR  
ATCO 08-Mar-27 10:00 17-Mar-27 17:00 9.25 Days
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
 
SUNCOR 06-Apr-27 09:00 16-Apr-27 20:00 10.46 Days
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 7.29 Days
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 9.17 Days
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  
ATCO 03-May-27 09:00 17-May-27 17:30 14.35 Days
Continuous
2075s T11 (2075s Newell) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 14.35 Days
Continuous
2029s T11 (2029s Heathfield) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 14.35 Days
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 3.29 Days
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 14-May-27 20:00 10.46 Days
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  
SUNCOR 05-May-27 14:00 14-May-27 18:00 9.17 Days
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 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  
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  
SUNCOR 01-Jun-27 08:00 10-Jun-27 17:00 9.38 Days
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 10.46 Days
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  
SUNCOR 11-Jun-27 08:00 20-Jun-27 17:00 9.38 Days
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.  
SUNCOR 15-Jun-27 09:00 25-Jun-27 20:00 10.46 Days
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  
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  
ALTALINK, ATCO, FMGW 17-Aug-27 08:00 18-Aug-27 17:00 1.38 Days
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 08-Nov-27 09:00 11-Nov-27 17:00 3.33 Days
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 3.33 Days
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 2.33 Days
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 16.21 Days
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 3.29 Days
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 2.33 Days
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 31.29 Days
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 3.33 Days
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 3.33 Days
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  
ATCO 18-Apr-28 10:00 25-Apr-28 17:00 7.29 Days
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 3.29 Days
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
 
ATCO 08-May-28 09:00 10-Jul-28 17:00 63.33 Days
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 63.33 Days
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 4.29 Days
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 2.33 Days
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 2.33 Days
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 10.33 Days
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 11.25 Days
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 14.29 Days
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 15.25 Days
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, GREENGATEP 01-Oct-28 08:00 21-Oct-28 16:00 20.33 Days
Continuous
972S 904, 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
 

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: 2026-04-22   14:00:47


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.

© 2009 Alberta Electric System Operator. All rights reserved