Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2025-08-30

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
EPCOR 31-Mar-25 07:00 03-Oct-25 17:00 186.42 Days
Continuous		 987s T1 (987s Clover Bar), 987s CCP7213 (987s Clover Bar), 987s CCP7214 (987s Clover Bar) Cloverbar - TX1 LCR  
NWE 16-Jul-25 07:00 19-Sep-25 17:00 65.42 Days
Continuous		 2366 (NWE Marias) install new equipment at Marias AB-MATL
ALTALINK 17-Jul-25 08:30 31-Aug-25 16:30 45.33 Days
Daily		 74s C3 (74s Janet) forced outage  
ALTALINK, TRANSALTA 29-Jul-25 08:00 25-Sep-25 17:00 58.38 Days
Continuous		 33s 2 (33s Spray), 33s T2 (33s Spray) maintenance  
ATCO 02-Aug-25 23:30 12-Sep-25 18:00 40.77 Days
Continuous		 827s SVC (827s Cranberry Lake) forced outage  
ALTALINK 14-Aug-25 14:00 25-Sep-25 17:00 42.13 Days
Continuous		 33s 3 (33s Spray) condition assessment and T1 compliance testing  
ATCO 18-Aug-25 14:01 01-Sep-25 14:00 14 Days
Continuous		 732s 902T (732s Mitsue), 732s 503R (732s Mitsue), 732s 704 (732s Mitsue), 732s 705 (732s Mitsue), 732s 901 (732s Mitsue), 732s 906 (732s Mitsue), 732s 702TD (732s Mitsue), 732s 902TD (732s Mitsue), 732s 906A (732s MItsue), 732s 901A (732s MItsue) protection upgrade  
ALTALINK 20-Aug-25 08:00 01-Sep-25 17:00 12.38 Days
Continuous		 799s 138kV Bus (799s Coleman), 170L (632s Russell - 799s Coleman), 799s T3 (799s Coleman), 799s 170E (799s Coleman) remove s29 from foundation, repair foundation, install s29 and adjust, remove 25kV temp feed AB-BC
SUNCOR 28-Aug-25 08:00 16-Sep-25 20:00 19.5 Days
Continuous		 29PL9-24 (29EDD-94 Voyageur - 29EDD-60 Inglis Island), 29EDD-60 29PT-702 (29EDD-60 Inglis Island), 29EDD-60 30-252-400001 (29EDD-60 Inglis Island) 29pt-702 - repair / replace burned bonding conductor (9000807989)  
ENMAX, ALTALINK 30-Aug-25 08:00 30-Aug-25 12:00 4 Hours
Continuous		 28.80L (42s Sarcee - SS-28), 28.2TR (SS-28) Substation - Insulator Washing (Fall)  
ENMAX, ALTALINK 30-Aug-25 08:00 30-Aug-25 12:00 4 Hours
Daily		 28.80L (42s Sarcee - SS-28) Substation - Insulator Washing (Fall)  
ATCO 01-Sep-25 14:01 15-Sep-25 14:00 14 Days
Continuous		 732s 902T (732s Mitsue), 732s 503R (732s Mitsue) Protection upgrade. Remove old protection, cut over to new protection and cut over equipment status, control and alarms to new station controller.  
ATCO, ALTALINK 02-Sep-25 07:00 10-Sep-25 18:00 8.46 Days
Continuous		 1036L (356s Milo - 554s Travers) South Crew will be doing component replacement on 1036L (STR 5 - 101)See also 294976 1005L RB required due to proximity  
EPCOR 02-Sep-25 07:00 14-Sep-25 17:00 12.42 Days
Continuous		 EP 803s T2 (EP 803s Lambton), EP 803s L2402 (EP 803s Lambton), EP 803s L2405 (EP 803s Lambton) Lambton: LAB2 LCR and TX2 Zone Doble and LDS4/LDS9 Disconnect and Tap Changer Maintenance  
EPCOR 02-Sep-25 07:00 26-Sep-25 17:00 24.42 Days
Continuous		 805s T1 (805s Jasper) Jasper: TX1 Bushing Replacement (PCB)  
EPCOR 02-Sep-25 07:00 12-Oct-25 17:00 40.42 Days
Continuous		 557s T2 (557s Castle Downs) Castle Downs S/S Tx2 Bay Outage  
ALTALINK 02-Sep-25 07:30 12-Sep-25 16:00 10.35 Days
Continuous		 1325L (510s Sunnybrook - AML 511s Crossings) 510s DIW Piping Repair, Annual Link Outage for various maintenance.  
BCH 02-Sep-25 09:00 05-Sep-25 17:00 3.33 Days
Continuous		 5L91 (BCH Ashton Creek - BCH Selkirk) replace marker balls AB-BC
BCH 02-Sep-25 09:00 17-Sep-25 09:00 15 Days
Continuous		 T3 (BCH Natal), 12CB23 (BCH Natal) natal substation replacement and ETM install AB-BC
ATCO 02-Sep-25 10:00 12-Sep-25 17:00 10.29 Days
Daily		 9L16 (755s Cordel - 972s Tinchebray) Install foundations for new 9L16 structures 73 and 74 in preparation of the future line bay re-termination into 972S Tinchebray expansion.
Will return line to service in the evenings		  
BCH 02-Sep-25 10:00 01-Oct-25 15:00 29.21 Days
Continuous		 5L72 (BCH Mica G.S. - BCH Nicola) MCA 500kV Switching Outage for Opening 5D5 for D12Y & Project work. AB-BC
BCH 02-Sep-25 10:00 01-Oct-25 16:00 29.25 Days
Continuous		 5L72 (BCH Mica G.S. - BCH Nicola) MCA F26 AOP Placeholder  
BCH 02-Sep-25 10:00 01-Oct-25 16:00 29.25 Days
Continuous		 5L72 (BCH Mica G.S. - BCH Nicola) MCA 5CB9 Project GM-0463  
ALTALINK 02-Sep-25 11:00 02-Sep-25 15:00 4 Hours
Daily		 801L (62s Brazeau Plant - 294s Brazeau Plant Outlet Works) high side mobile disconnect  
ALTALINK, GLPC 02-Sep-25 12:00 02-Sep-25 17:00 5 Hours
Daily		 688L (199s East Airdrie - 688BL tap), 1055s T1 (1055s Sollair) Replace PCB Lighting fixtures located within LOA at 199s  
ALTALINK 03-Sep-25 07:30 03-Sep-25 12:00 4.5 Hours
Daily		 71s 138kV East Bus (71s Lamoureux), 71s 240kV East Bus (71s Lamoureux), 71s T2 (71s Lamoureux), 71s 852 (71s Lamoureux), 71s 452 (71s Lamoureux), 71s 1752 (71s Lamoureux), 71s 1452 (71s Lamoureux) Exercising all equipment within this GOI and documenting any potential issues prior to start of new DOW Project  
ATCO 03-Sep-25 08:00 03-Sep-25 16:00 8 Hours
Continuous		 7L58 (789s Keg River - 905s Meikle) Emergency Pole replacement on 7L58 fire restoration
This is rescheduled from the cancelled 1-00498577 due to inclemant weather		  
ATCO 03-Sep-25 09:00 11-Sep-25 08:00 7.96 Days
Continuous		 951S 907 (951s Thickwood Hills) Installation of new POW relay/Protection  
ATCO 03-Sep-25 09:30 04-Sep-25 17:30 1.33 Days
Continuous		 802s 704 (802s Michichi Creek), 7L128 (802s Michichi Creek - 7LA128 tap) BREAKER MIN OIL HLR PARTIAL TESTING - BREAKER 704 @ 802S  
ALTALINK, EPCOR 03-Sep-25 12:01 03-Sep-25 15:30 3.48 Hours
Daily		 71s 138kV West Bus (71s Lamoureux), 71s 240kV West Bus (71s Lamoureux), 71s T1 (71s Lamoureux), 921L (71s Lamoureux - 987s Clover Bar), 781L (71s Lamoureux - 172s Sherritt), 71s 252 (71s Lamoureux), 71s 152 (71s Lamoureux), 71s 1352 (71s Lamoureux), 71s 1252 (71s Lamoureux) Exercising all equipment within this GOI and documenting any potential issues prior to start of new DOW Project  
ALTALINK 03-Sep-25 13:30 04-Sep-25 16:30 27 Hours
Continuous		 370s 2152 (370s North Lethbridge), 370s T3 (370s North Lethbridge) First Trip, Breaker Maint. and investigate T3 oil leak.  
ALTALINK, EPCOR 03-Sep-25 15:31 03-Sep-25 17:30 119 Mins
Daily		 71s 1552 (71s Lamoureux), 71s 1652 (71s Lamoureux), 920L (71s Lamoureux - 557s Castle Downs) Exercising all equipment within this GOI and documenting any potential issues prior to start of new DOW Project  
ALTALINK 06-Sep-25 12:01 06-Sep-25 16:30 4.48 Hours
Daily		 71s 1452 (71s Lamoureux), 71s 1352 (71s Lamoureux), 71s 997E (71s Lamoureux), 997L (71s Lamoureux - 430s Ursus) Remove PCB ballast fixture on steel structure adjacent to 71s997E. Isolations required to allow for safe limits of approach for removal  
ATCO 07-Sep-25 09:00 10-Sep-25 17:00 3.33 Days
Continuous		 951s 1205 (951s Thickwood Hills) 1205 Outage for POW relay addition project  
EPCOR 08-Sep-25 07:00 09-Sep-25 17:00 1.42 Days
Continuous		 52s T1 (52s East Industrial) East Industrial: TX1 - MV Protection Upgrade Cutovers  
ALTALINK, EPCOR 08-Sep-25 07:00 12-Sep-25 17:00 4.42 Days
Continuous		 947L (89s Ellerslie - 987s Clover Bar), 987s C2402 (987s Clover Bar), 987s C2404 (987s Clover Bar) Cloverbar: 947L Zone Doble and CDS27/CDS28/CDS29 Disconnect Maintenance  
ALTALINK, EPCOR 08-Sep-25 07:00 13-Sep-25 17:00 5.42 Days
Continuous		 657s SU2403 (657s Summerside), 657s SU2402 (657s Summerside), 657s T2 (657s Summerside) Summerside: TX2 Zone Doble and Disconnect Maintenance  
ATCO, ALBIAN 08-Sep-25 08:00 09-Sep-25 16:00 1.33 Days
Continuous		 919s 908 (919s Hartley) CNRL requested outage to breaker 908 at 919S to remove potential for Protection trips during function testing of new G60-A relay.  
Lethbridge 08-Sep-25 08:00 09-Sep-25 17:00 1.38 Days
Continuous		 241s 734L (241s Uplands) Open end outage on 734L to Cutover SCADA points from SURVALENT Scout to SEL RTAC and test and commission protections  
ATCO, ALBIAN 08-Sep-25 08:00 14-Sep-25 16:00 6.33 Days
Continuous		 920s 902T (920s Jackpine) request from CNRL
carry out the repairs on 72kV cables connected to 902T		  
BCH 08-Sep-25 09:00 18-Sep-25 17:00 10.33 Days
Continuous		 5L92 (BCH Cranbrook - BCH Selkirk) replace insulators & spacers AB-BC
BCH 08-Sep-25 09:00 18-Sep-25 17:00 10.33 Days
Continuous		 5L92 (BCH Cranbrook - BCH Selkirk), T3 (BCH Cranbrook) CBK Insulator Replacement project Step #5 AB-BC
ATCO 08-Sep-25 09:30 09-Sep-25 17:30 1.33 Days
Continuous		 755s 902 (755s Cordel) BREAKER SF6 GL315 COMPLETE TESTING - BREAKER 902 @ 755S
TCM Program. RTXP Test Switch Mitigation and Replacement: 50BF/902 @ 755S		  
ALTALINK, EPCOR 08-Sep-25 09:30 12-Sep-25 17:00 4.31 Days
Continuous		 947L (89s Ellerslie - 987s Clover Bar) Cloverbar: 947L Zone Doble and CDS27/CDS28/CDS29 Disconnect Maintenance  
ALTALINK 08-Sep-25 12:30 08-Sep-25 16:30 4 Hours
Daily		 17s 2 (17s Benalto) Techs to take oil sample from CT252 associated with 17s2 240kV breaker.  
ALTALINK 09-Sep-25 07:30 09-Sep-25 12:30 5 Hours
Daily		 650s 252 (650s Hansman Lake) Settings changes and breaker protection testing on 650s252  
ALTALINK 09-Sep-25 07:30 09-Sep-25 17:30 10 Hours
Daily		 63s T2 (63s Red Deer) Repair cracked/chipping 240kV Bushing heads  
ATCO, ALTALINK 09-Sep-25 09:00 10-Sep-25 18:00 1.38 Days
Continuous		 7L760D4 (7LA760 tap), 7L760D5 (7LA760 tap), 7L760 (7LA760 tap - 7LC760 tap), 760L (760AL tap - 7LA760 tap) Building Temp Bypass to replace switches 7L760D4, 7L760D5 and 7LA760D1.
Will Need COG from AltaLink at 760L41		  
ALTALINK 09-Sep-25 12:30 09-Sep-25 17:30 5 Hours
Daily		 650s 352 (650s Hansman Lake) Settings changes and breaker protection testing on 650s352  
ALTALINK, TRANSALTA 09-Sep-25 23:00 11-Sep-25 07:00 1.33 Days
Continuous		 250p T2 (250p Bighorn Plant) maintenance  
ALTALINK, TRANSALTA 10-Sep-25 07:00 11-Sep-25 07:00 24 Hours
Continuous		 250p T1 (250p Bighorn Plant) maintenance  
ALTALINK 10-Sep-25 07:30 10-Sep-25 17:30 10 Hours
Daily		 63s 352 (63s Red Deer) Top up low gas and repair nitrogen leaks  
ALTALINK, Lethbridge 10-Sep-25 08:00 11-Sep-25 17:00 1.38 Days
Continuous		 667L (146s MacDonald - 370s North Lethbridge) Open End Outage on 667L to Cutover SCADA points from SURVALENT Scout to SEL RTAC.  
SUNCOR 10-Sep-25 08:00 19-Sep-25 20:00 9.5 Days
Continuous		 29EDD-34 29PT-341 (29EDD-34), 29EDD-34 29-952-142 (29EDD-34), 29EDD-34 29-952-143 (29EDD-34), 29EDD-34 29PS-0375 (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-0380 (29EDD-34), 29EDD-34 29PS-0381 (29EDD-34), 29EDD-34 29PS-0382 (29EDD-34), 29EDD-34 29PS-609 (29EDD-34), 29EDD-34 29PS-610 (29EDD-34) 10 year PM on 29EDD34;29PT-341 system and 5 year, 10 year PM on 29EDD34;29PP-103 system
  
ALTALINK 10-Sep-25 08:30 10-Sep-25 12:30 4 Hours
Daily		 338s 552 (338s Cherhill) CT oil sample  
ATCO 10-Sep-25 09:00 10-Sep-25 09:15 15 Mins
Continuous		 7L01 (813s Little Smoky - 881s Sturgeon 2) This will require 7L01 to be deenergized for 10-15mins while 881s 701TD is opened.  
ATCO 10-Sep-25 11:00 10-Sep-25 12:00 60 Mins
Continuous		 774s 701 (774s Monitor), 7L224 (650s Hansman Lake - 774s Monitor) PRC-005 - TRIP COIL TESTING - BREAKER 701 @ 774S  
ALTALINK 10-Sep-25 12:00 10-Sep-25 15:00 3 Hours
Continuous		 199L (347s AML Fox Creek - 741s ATC Fox Creek) Update 347s199W breaker maintenance switch and associated circuits.  
ALTALINK 10-Sep-25 15:00 10-Sep-25 17:30 2.5 Hours
Continuous		 199L (347s AML Fox Creek - 199AL tap), 347s 199E (347s AML Fox Creek) update 347s199E breaker maintenance switch and associated circuits  
ATCO 11-Sep-25 08:01 11-Sep-25 13:00 4.98 Hours
Continuous		 951s 1201T (951s Thickwood Hills) 900BS1 Outage for commissioning POW project  
ATCO 11-Sep-25 08:45 11-Sep-25 09:00 15 Mins
Continuous		 7L01 (813s Little Smoky - 881s Sturgeon 2) This will require 7L01 to be deenergized for 10-15mins while 881s 701TD is closed.  
ATCO 11-Sep-25 09:00 11-Sep-25 13:00 4 Hours
Continuous		 12L44 (939s Livock - 951s Thickwood Hills) 500KV Bus inspection  
ATCO 11-Sep-25 13:01 12-Sep-25 14:00 24.98 Hours
Continuous		 951s 1201T (951s Thickwood Hills) Proof of concept commissioning. Energizing 1201T and the system through 907 & 1205 Breakers with new POW Relays
Breakers will be Opened/Closed through out testing.		  
BCH 12-Sep-25 09:00 17-Sep-25 17:00 5.33 Days
Continuous		 2L113 (BCH Cranbrook - BCH Natal) NTL station rebuild AB-BC
BCH 12-Sep-25 13:00 26-Sep-25 17:00 14.17 Days
Continuous		 T4 (BCH Natal) Natal substation replacement and ETM install AB-BC
ALTALINK 13-Sep-25 08:00 13-Sep-25 13:00 5 Hours
Daily		 38s T1 (38s East Edmonton) Extend 38sT1 CT wiring to DDR. Must be done to meet PRC002 compliance  
ALTALINK 13-Sep-25 13:30 13-Sep-25 18:00 4.5 Hours
Daily		 38s T4 (38s East Edmonton) Extend 38sT1 CT wiring to DDR. Must be done to meet PRC002 compliance  
ALTALINK 14-Sep-25 08:30 14-Sep-25 18:30 10 Hours
Daily		 89s T2 (89s Ellerslie) PRC005 testing of GDRs, gas detector replacement on 1 phase, testing of sudden pressure relief devices.  
EPCOR 15-Sep-25 07:00 16-Sep-25 17:00 1.42 Days
Continuous		 52s T2 (52s East Industrial) East Industrial: TX2 - MV Protection Upgrade Cutovers  
EPCOR 15-Sep-25 07:00 20-Sep-25 17:00 5.42 Days
Continuous		 987s T1 (987s Clover Bar), 987s CCP7213 (987s Clover Bar), 987s CCP7214 (987s Clover Bar), 987s C2401 (987s Clover Bar), 987s C2403 (987s Clover Bar), 987s C2402 (987s Clover Bar), 987s T3 (987s Clover Bar) Cloverbar: TX1 and TX3 Zone, Insulator Stand Install and CT Removal  
ALTALINK 15-Sep-25 09:30 18-Sep-25 12:30 3.13 Days
Continuous		 33s 1 (33s Spray) Replacement 2 more CTs associated with 33s1 Breaker.  
ALTALINK, EPCOR 15-Sep-25 09:30 21-Sep-25 17:00 6.31 Days
Continuous		 909L (310p Sundance - 665s Dome), 665s D2402 (665s Dome), 665s D2403 (665s Dome), 665s T2 (665s Dome) Dome: 909LE/TX2 Doble and DDS4/DDS5/DAB2 Disconnect Maintenance and Relay Maintenance  
ALTALINK, EPCOR 15-Sep-25 09:30 21-Sep-25 17:00 6.31 Days
Continuous		 909L (310p Sundance - 665s Dome) Dome: 909LE/TX2 Doble and DDS4/DDS5/DAB2 Disconnect Maintenance and Relay Maintenance  
ATCO 15-Sep-25 10:00 03-Oct-25 17:30 18.31 Days
Continuous		 840s McNeill Station CONVERTER INSPECTION @ MCNEILL 840S
BREAKER SF6 HPL COMPLETE TESTING -		 AB-SK
BCH 15-Sep-25 13:00 15-Sep-25 14:00 60 Mins
Continuous		 2L112 (BPA Boundary - BCH Nelway) EMERGENCY REPLACEMENT OF A BOUNDARY PCB AND IN ORDER TO MOVE IT INTO LOCATION WE NEED TO CLEAR PCB A-1220 WHICH WILL OPEN END THE BOUNDARY-NELWAY NO 1 230KV LINE. AB-BC
BCH 15-Sep-25 13:00 15-Sep-25 14:00 60 Mins
Continuous		 2L112 (BPA Boundary - BCH Nelway) PROXIMITY WORK REMOVING OLD BREAKER ON TRAILER UNDER MAIN BUS SIDE OF PCB A-1220 AB-BC
ALTALINK 15-Sep-25 18:00 18-Sep-25 17:00 2.96 Days
Continuous		 421s T2 (421s Hays) Urgent replacement of 421s14 due to bird contact and switch contact cleaning of 421s18 due to maintenance identified hotspot.  
BCH 16-Sep-25 00:00 16-Sep-25 00:00 0 Mins
Continuous		 5L72 (BCH Mica G.S. - BCH Nicola) MCA 500kV Switching Outage for Opening 5D5 for D12Y & Project work. AB-BC
ALTALINK, TRANSALTA 16-Sep-25 07:00 17-Sep-25 18:00 1.46 Days
Daily		 514L (396s Pincher Creek - 514BL tap), 514L (513s Lundbreck - 514BL tap), 322s T1 (322s Cowley Ridge) Replacing structures 16 and 76 Replacing arms and insulators on structure 170  
ALTALINK 16-Sep-25 08:00 18-Sep-25 17:30 2.4 Days
Continuous		 359s T2 (359s Esso West Pembina), 359s 202AX (359s Esso West Pembina) Bushing replacement, Doble, maintenance, leaks, LTC maintenance  
ALTALINK 16-Sep-25 09:00 16-Sep-25 17:30 8.5 Hours
Daily		 68s T2 (68s Willesden Green) First Trip & PRC Breaker Maintenance  
BCH 16-Sep-25 09:00 19-Sep-25 17:00 3.33 Days
Continuous		 5L72 (BCH Mica G.S. - BCH Nicola) F26 AOP NERC CN PM on NIC 5CB3, 5CB13 and 5B43. CPC to enter PN's OOS OAT
 
SUNCOR 17-Sep-25 08:00 24-Sep-25 18:00 7.42 Days
Continuous		 29PL7-4 (29EDD-65 - 29EDD-71), 29EDD-65 29PS-0284 (29EDD-65 Edd65Sub), 29EDD-71 29PS-243 (29EDD-71 Edd71Sub), 29EDD-65 29PT-0257 (29EDD-65) FB-Maintenance, Repairs and Testing - PRC-5 Testing, 29PT-260, 29PL7-4, 29PT-241, 29PT-257, 29PS-243 (300415541, 31807283, 31773784, 300109525)  
ALTALINK 17-Sep-25 09:00 17-Sep-25 17:30 8.5 Hours
Daily		 62s 31 (62s Brazeau Plant), 62s T3 (62s Brazeau Plant) 240kV breaker maintenance (N.O.)  
CNRL 18-Sep-25 08:00 22-Sep-25 16:00 4.33 Days
Continuous		 842s 75-1904 (842s Horizon Upgrading) breaker tank heater repair  
SUNCOR 18-Sep-25 08:00 05-Oct-25 20:00 17.5 Days
Continuous		 29EDD-61 29PT-653 (29EDD-61 Stony Island) 29PT-653 - Repair / Replace Burned Bonding Conductor (9000808061)  
ALTALINK 18-Sep-25 09:00 18-Sep-25 17:30 8.5 Hours
Daily		 62s T5 (62s Brazeau Plant) Install Bushing monitoring devices  
ALTALINK 19-Sep-25 07:00 25-Sep-25 17:00 6.42 Days
Continuous		 520s T1 (520s Bennett), 520s R7 (520s Bennett) South 520sT1 + R7 doble, maintenance and leaks  
ALTALINK 19-Sep-25 07:00 30-Sep-25 17:00 11.42 Days
Continuous		 1201L (520s Bennett - BCH Cranbrook) South Crew will be completing component replacement from 1201L21 – 1201L435 AB-BC
ALTALINK 19-Sep-25 07:00 30-Sep-25 17:00 11.42 Days
Continuous		 799s 786W (799s Coleman), 786L (799s Coleman - BCH Natal) 786L required to be open due to 1201L as per AESO Rule AB-BC
BHE Canada 19-Sep-25 07:00 30-Sep-25 17:00 11.42 Days
Continuous		 MATL (120s Picture Butte - Montana) align with 1201L outage AB-MATL
AESO 19-Sep-25 07:00 30-Sep-25 17:00 11.42 Days
Continuous		 Path 1 (AIES Islanding) align with 1201L outage AB-BC
SUNCOR 20-Sep-25 08:00 30-Sep-25 20:00 10.5 Days
Continuous		 29EDD-34 29PT-340 (29EDD-34) 29EDD34;29PT-340 SYSTEM;PM 5y,10y; 29EDD34;29PP-102 SYSTEM;PM 5y,10y
  
ENMAX, ALTALINK 21-Sep-25 08:00 07-Oct-25 16:00 16.33 Days
Continuous		 50L (44s Bearspaw Plant - SS-21), 21.1C (SS-21), 21.2TR (SS-21) 21.2TR Replacement. Decommission, remove existing 21.2TR and associated equipment  
ENMAX, ALTALINK 21-Sep-25 08:00 07-Oct-25 16:00 16.33 Days
Continuous		 50L (44s Bearspaw Plant - SS-21) ENMAX - 21.2TR Replacement. Decommission, remove existing 21.2TR and associated equipment  
ENMAX, ALTALINK 21-Sep-25 08:00 07-Oct-25 16:00 16.33 Days
Continuous		 50L (44s Bearspaw Plant - SS-21) 21.2TR Replacement. Decommission, remove existing 21.2TR and associated equipment. 21.80L & 20.82L will be open ended 50L FCT 27 cycles. 60s100 source will be moved to 21PT138-Z31 sec. fuses.  
EPCOR 22-Sep-25 07:00 03-Oct-25 17:00 11.42 Days
Continuous		 987s T1 (987s Clover Bar), 987s C2401 (987s Clover Bar), 987s C2403 (987s Clover Bar), 987s CCP7213 (987s Clover Bar), 987s CCP7214 (987s Clover Bar) Cloverbar: TX1 LCR P&C Commissioning and Initial Energization  
ALTALINK 22-Sep-25 12:00 22-Sep-25 18:00 6 Hours
Daily		 74s 23.80W (74s Janet) Substation - Insulator Washing (Fall).  
ALTALINK 22-Sep-25 12:30 25-Sep-25 16:30 3.17 Days
Continuous		 310p T30 (310p Sundance) Bushing replacement, maintenance, and leak repair  
ATCO 22-Sep-25 13:00 25-Sep-25 16:00 3.13 Days
Continuous		 7L28 (717s Ethel Lake - 846s Grand Centre) 7L28 Line to ground clearance mitigation  
ALTALINK, EPCOR 22-Sep-25 13:00 25-Sep-25 17:00 3.17 Days
Continuous		 1043L (320p Keephills - 367s Harry Smith), 320p 352 (320p Keephills), 320p 252 (320p Keephills) Replace 320p289  
ATCO 23-Sep-25 09:00 26-Sep-25 17:00 3.33 Days
Continuous		 9L99 (801s Anderson - 807s Sheerness) 801S DFR requires 9L99 inputs to meet PRC-002 compliance  
ALTALINK 23-Sep-25 09:30 25-Sep-25 16:30 2.29 Days
Daily		 1071L (205s Castle Rock Ridge - 312s Fidler) 205s352, 452 First Trip, CT testing, repair 205s7 seized switch  
ENMAX 23-Sep-25 12:00 23-Sep-25 18:00 6 Hours
Continuous		 23.80L (74s Janet - SS-23), 23.4TR (SS-23) Substation - Insulator Washing (Fall)  
ALTALINK 25-Sep-25 06:15 27-Sep-25 17:45 2.48 Days
Continuous		 862L (166s Dow Chemical Fort Saskatchewan - 258s Dow Hydrocarbons) Line Move to modify the existing alignment between structures 4-8  
ALTALINK, TRANSALTA 26-Sep-25 09:00 26-Sep-25 12:00 3 Hours
Daily		 33s T1 (33s Spray) testing  
ALTALINK, TRANSALTA 26-Sep-25 13:00 26-Sep-25 16:00 3 Hours
Daily		 33s T2 (33s Spray) testing  
ALTALINK 27-Sep-25 07:00 12-Oct-25 18:00 15.46 Days
Continuous		 912L (63s Red Deer - 766s Nevis) Arctic Arrow will be stringing overtop 912L STR 147-148 with the new CETO 962L/986L spans 165-166.  
ALTALINK 28-Sep-25 06:15 29-Sep-25 17:45 1.48 Days
Continuous		 707L (54s Fort Saskatchewan - 166s Dow Chemical Fort Saskatchewan) Line Move to modify the existing alignment between structures 29-33  
ATCO 28-Sep-25 09:00 05-Oct-25 15:00 7.25 Days
Continuous		 7L20 (740s H.R. Milner - 810s Dome Cutbank) Outage on 7L20 for line maintenance program to change out following Structures.
69,66,65,64,62,60,59,54,53		  
EPCOR 29-Sep-25 07:00 05-Oct-25 17:00 6.42 Days
Continuous		 816s P2404 (816s Petrolia), 816s P2405 (816s Petrolia), 816s T2 (816s Petrolia) Petrolia: TX2 Zone Doble and Disconnect Maintenance  
EPCOR 29-Sep-25 07:00 12-Oct-25 17:00 13.42 Days
Continuous		 557s T2 (557s Castle Downs) Castle Downs S/S Tx2 bay outage  
Lethbridge 29-Sep-25 08:00 30-Sep-25 17:00 1.38 Days
Continuous		 593s 824L (593s Lakeview) Open End Outage on 824L to Cutover SCADA points from SURVALENT Scout to SEL RTAC and to test and commission. Require Protection outages on 824L "A" Protection relay (SEL 411L) , "B" Protection relay (GE L90), "152" Breaker Protection relay (GE C60) .Redundant Protection will be in place at all time  
ALTALINK, Lethbridge 29-Sep-25 08:00 30-Sep-25 17:00 1.38 Days
Continuous		 824L (593s Lakeview - 618s Riverbend) Open End Outage on 824L to Cutover SCADA points from SURVALENT Scout to SEL RTAC and to test and commission  
ATCO 29-Sep-25 13:00 02-Oct-25 16:00 3.13 Days
Continuous		 7L28 (717s Ethel Lake - 846s Grand Centre) 7L28 Line to ground clearance mitigation  
ATCO 29-Sep-25 14:01 13-Oct-25 14:00 14 Days
Continuous		 732s 701 (732s Mitsue), 732s 702 (732s Mitsue), 732s 901T (732s Mitsue), 732s 902 (732s Mitsue), 732s 903 (732s Mitsue) Protection upgrade. Remove old protection, cut over to new protection and cut over equipment status, control and alarms to new station controller.  
ALTALINK 30-Sep-25 06:15 02-Oct-25 17:45 2.48 Days
Continuous		 787L (166s Dow Chemical Fort Saskatchewan - 787AL tap) Line Move to modify the existing alignment between structures 35-39  
ALTALINK 30-Sep-25 07:00 01-Oct-25 18:00 1.46 Days
Continuous		 180AL (604s Granum - 180L tap), 180L (928s East Stavely - 180AL tap), 180L (15s Fort Macleod - 180AL tap) In this outage we will be updating our Protection Relay settings  
ALTALINK 30-Sep-25 07:00 09-Oct-25 18:00 9.46 Days
Continuous		 935L (324s Cassils - 356s Milo) Performing mtce. between Structures #53 - 148  
ALTALINK, TRANSALTA 30-Sep-25 16:00 25-Oct-25 18:00 25.08 Days
Continuous		 320p GT3 (320p Keephills) maintenance  
ALTALINK, EPCOR 01-Oct-25 07:00 02-Oct-25 17:00 1.42 Days
Continuous		 1045L (310p Sundance - 1045AL tap), 1045L (EP 805s Jasper - 1045AL tap), 1045AL (320p Keephills - 1045L tap), EP 805s J2406 (EP 805s Jasper), EP 805s J2407 (EP 805s Jasper) insulator repair  
ALTALINK, EPCOR 01-Oct-25 07:00 02-Oct-25 18:00 1.46 Days
Continuous		 1045AL (320p Keephills - 1045L tap), 1045L (310p Sundance - 1045AL tap), 1045L (EP 805s Jasper - 1045AL tap) Aerial: Insulator Repair and Relay: Op Checks  
ENMAX, ALTALINK 01-Oct-25 08:00 01-Oct-25 16:00 8 Hours
Continuous		 1080L (SS-25 - SS-65) Surge Arrestor Power Factor Test - 65MD240-1080  
ALTALINK 01-Oct-25 08:00 11-Nov-25 17:00 41.42 Days
Continuous		 102s SVC (102s Langdon), 102s T4 (102s Langdon) the controls change AB-BC
ALTALINK 01-Oct-25 11:00 02-Oct-25 18:00 31 Hours
Continuous		 38s 7652 (38s East Edmonton) 240kV breaker maintenance, rebuild dashpot  
ALTALINK 01-Oct-25 12:00 03-Oct-25 18:30 2.27 Days
Continuous		 89s T2 (89s Ellerslie) 89s T2 Doble and maintenance. Replace gas detector relay. Update Qualitrol settings. Repair oil leaks.  
ALTALINK 02-Oct-25 07:00 02-Oct-25 12:00 5 Hours
Daily		 722L (107s Westfield - 368s Burdett) Remove PCB Lighting fixture located within LOA at 107s  
ENMAX, ALTALINK 02-Oct-25 08:00 02-Oct-25 18:00 10 Hours
Continuous		 1080L (SS-25 - SS-65) Surge Arrestor Power Factor Test - 25MD240-1080  
ALTALINK 02-Oct-25 08:15 02-Oct-25 13:45 5.5 Hours
Daily		 853L (28s West Brooks - 853AL tap), 853L75 (853AL tap), 28s 25 (28s West Brooks), 28s 28 (28s West Brooks) Insulator replacement  
ALTALINK 02-Oct-25 09:30 02-Oct-25 15:30 6 Hours
Daily		 632s 412 (632s Russell), 412L (396s Pincher Creek - 632s Russell) Heater replacement  
BCH, ALTALINK 03-Oct-25 06:00 03-Oct-25 18:00 12 Hours
Continuous		 1L274 (48s Pocaterra - 978s BCH Britt Creek), 48s 887X (48s Pocaterra) Placeholder to energize new equipment at FRO (Bauer Tower Equipment, BCH Metering Kit and Surge Arrestor, FRO FCD-H31 AB-BC
ALTALINK 03-Oct-25 07:00 03-Oct-25 18:00 11 Hours
Continuous		 887L (48s Pocaterra - 978s BCH Britt Creek) FRO project work. BCH to close their switch 1D23 de-energized AB-BC
ENMAX, ALTALINK 03-Oct-25 08:00 03-Oct-25 12:00 4 Hours
Continuous		 28.80L (42s Sarcee - SS-28), 28B138-28.80 (SS-28) HV Breaker SF6 Gas Sample - 28B138-28.80  
ALTALINK 03-Oct-25 08:00 03-Oct-25 14:00 6 Hours
Daily		 1052L (28s West Brooks - 324s Cassils) Replace 28s 1052L Strain Insulators, See also 294659 827L RB, & 1051L (28s-324s) - RB Required due to proximity.  
ENMAX 03-Oct-25 08:00 03-Oct-25 16:00 8 Hours
Continuous		 23.80L (74s Janet - SS-23) Shield wire corrosion testing  
ALTALINK 03-Oct-25 08:00 03-Oct-25 16:00 8 Hours
Daily		 74s 30 (74s Janet) Shield wire corrosion testing  
EPCOR 06-Oct-25 07:00 06-Oct-25 17:00 10 Hours
Continuous		 72DS26 (665s Dome - Strathcona), 665s D721 (665s Dome), S721 (Strathcona) Dome/DS26: DDS17 Repair  
ALTALINK 06-Oct-25 08:00 06-Oct-25 17:30 9.5 Hours
Daily		 801L (62s Brazeau Plant - 294s Brazeau Plant Outlet Works) allow wiring/testing/operation of 294s801N MOD  
ATCO 06-Oct-25 08:00 10-Oct-25 18:00 4.42 Days
Continuous		 7L228 (845s Big Mountain - 7L20 tap) Outage on 7L228 for line maintenance program to change out following Structures.
652,651,648,647,608,611,578,574,534,533,529,528,526,500,499,495,470,471,479,457,456,453,447,441,437,435,433,428		  
ATCO 06-Oct-25 09:00 09-Oct-25 16:00 3.29 Days
Continuous		 969s 701T (969s Lindbergh) replace failing bushings on transformer  
BCH 06-Oct-25 09:00 10-Oct-25 17:00 4.33 Days
Continuous		 5L91 (BCH Ashton Creek - BCH Selkirk) Replace markerballs & insulators AB-BC
BCH 06-Oct-25 09:00 17-Oct-25 17:00 11.33 Days
Continuous		 2L112 (BPA Boundary - BCH Nelway), 2D24 (BCH Nelway), 2D2CB7 (BCH Nelway) NLY 2SA2 2SA12 replacement, BC maintenance does not affect the Alberta ATC AB-BC
ATCO 06-Oct-25 09:30 07-Oct-25 17:30 1.33 Days
Continuous		 845s 703 (845s Big Mountain), 845s 710 (845s Big Mountain), 7L228 (845s Big Mountain - 7L20 tap) Replace Crank Mechanisms on 144 kV Switches at 845s Big Mountain - 703B
Replace Crank Mechanisms on 144 kV Switches at 845s Big Mountain - 704B		  
ATCO 06-Oct-25 09:30 07-Oct-25 17:30 1.33 Days
Continuous		 755s 901 (755s Cordel) BREAKER SF6 GL315 COMPLETE TESTING - BREAKER 901 @ 755S
TCM Program. RTXP Test Switch Mitigation and Replacement: 50BF/901 @ 755S		  
ALTALINK 07-Oct-25 06:00 11-Oct-25 18:00 4.5 Days
Continuous		 1034L (244s Bowmanton - 324s Cassils) Install new span of OPGW between 179-180, install splice boxes on structure 179 & 180, terminate the existing OPGW.  
ATCO 07-Oct-25 07:00 07-Oct-25 19:00 12 Hours
Continuous		 7L79 (771s Veteran - 892s Ribstone Creek), 7L696 (508s Lakesend - 892s Ribstone Creek) Installing interspacers on 7L79  
ALTALINK 07-Oct-25 08:00 08-Oct-25 17:00 1.38 Days
Daily		 725L (15s Fort MacLeod - 725BL tap), 725L (674s Bowron - 725BL tap) Component replacement #221-227.  
ALTALINK 07-Oct-25 08:30 07-Oct-25 17:30 9 Hours
Daily		 320p PS2 (320p Keephills), 320p 2652 (320p Keephills) 240kV breaker maintenance  
ATCO 07-Oct-25 09:30 07-Oct-25 17:30 8 Hours
Continuous		 801s 907 (801s Anderson) breaker testing  
ALTALINK 08-Oct-25 07:00 08-Oct-25 18:00 11 Hours
Continuous		 931L (28s West Brooks - 132s Ware Junction) South Crew will be repairing conductor at 931L66  
ALTALINK 08-Oct-25 07:00 11-Oct-25 17:00 3.42 Days
Continuous		 914L (86s Bigstone - 87s Gaetz), 87s 240kV East Bus (87s Gaetz), 87s T2 (87s Gaetz) East bus outage to install new screw piles for CETO project  
ATCO 08-Oct-25 09:30 09-Oct-25 17:30 1.33 Days
Continuous		 7L85 (801s Anderson - ATC 803s Bullpound), 801s 705 (801s Anderson) BREAKER SF6 LTB145D1/B COMPLETE TESTING - 705 @ 801S  
ALTALINK 08-Oct-25 23:00 09-Oct-25 03:00 4 Hours
Continuous		 62s T1 (62s Brazeau Plant) maintenance  
ALTALINK 09-Oct-25 03:00 09-Oct-25 07:00 4 Hours
Daily		 62s T2 (62s Brazeau Plant) maintenance  
ENMAX 09-Oct-25 08:00 09-Oct-25 18:00 10 Hours
Continuous		 7.84L (SS-7 - SS-36), 36B138-36BT3 (SS-36), 36.1TR (SS-36), 36.3TR (SS-36), 36B138-36.81 (SS-36) Substation - Insulator Washing (Fall)  
ALTALINK 12-Oct-25 07:00 15-Oct-25 17:00 3.42 Days
Continuous		 914L (63s Red Deer - 87s Gaetz), 87s 240kV West Bus (87s Gaetz), 87s T1 (87s Gaetz) West bus outage to install new screw piles for CETO project  
ATCO 13-Oct-25 11:00 30-Oct-25 17:30 17.27 Days
Continuous		 840s McNeill Station Replace failed control system parts  
ATCO 13-Oct-25 14:01 27-Oct-25 14:00 14 Days
Continuous		 732s 701 (732s Mitsue), 732s 702 (732s Mitsue), 732s 901T (732s Mitsue), 732s 501R (732s Mitsue) Protection upgrade. Remove old protection, cut over to new protection and cut over equipment status, control and alarms to new station controller.  
ALTALINK 14-Oct-25 06:00 17-Oct-25 18:00 3.5 Days
Continuous		 100L (498s Tilley - 895s Suffield) Install new tap structure for 100AL connections, and modify adjacent structures 242 & 243.  
EPCOR 14-Oct-25 07:00 14-Oct-25 17:00 10 Hours
Continuous		 805s T4 (805s Jasper) Jasper: TX4 Conservator Inspection  
ALTALINK, EPCOR 14-Oct-25 07:00 18-Oct-25 17:00 4.42 Days
Continuous		 1058L (657s Summerside - EP 803s Lambton), EP 803s L2403 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton) 1058L: Lambton CVT and Surge Arrestors LCR's  
ALTALINK 14-Oct-25 07:00 24-Oct-25 13:30 10.27 Days
Continuous		 924L (102s Langdon - 356s Milo), 102s 6952 (102s Langdon), 102s 6852 (102s Langdon), 356s 952 (356s Milo), 356s 852 (356s Milo) Line protection replacements and RAS175 scheme upgrades  
ATCO 14-Oct-25 08:00 17-Oct-25 18:00 3.42 Days
Continuous		 7L228 (845s Big Mountain - 7L20 tap) Outage on 7L228 for line maintenance program to change out following Structures.
652,651,648,647,608,611,578,574,534,533,529,528,526,500,499,495,470,471,479,457,456,453,447,441,437,435,433,428		  
ALTALINK, EPCOR 14-Oct-25 09:00 17-Oct-25 17:30 3.35 Days
Continuous		 920L (71s Lamoureux - 557s Castle Downs) EPCOR 920LE Zone Doble and disconnect maintenance.  
ALTALINK, EPCOR 14-Oct-25 09:30 17-Oct-25 17:00 3.31 Days
Continuous		 920L (71s Lamoureux - 557s Castle Downs), 557s CD2404 (557s Castle Downs), 557s CD2405 (557s Castle Downs) Castledowns: 920LE Zone Doble and Disconnect Maintenance  
ATCO 14-Oct-25 10:00 14-Oct-25 17:30 7.5 Hours
Continuous		 801s 910 (801s Anderson) BKR 910 Pole Low Oil at 801s Anderson  
ATCO 14-Oct-25 13:00 17-Oct-25 16:00 3.13 Days
Continuous		 7L28 (717s Ethel Lake - 846s Grand Centre) 7L28 Line to ground clearance mitigation  
ALTALINK 14-Oct-25 13:00 18-Oct-25 16:00 4.13 Days
Continuous		 65s 753E (65s High River), 753L (65s High River - 253s Blackie) Replace CTs and protection upgrade.  
EPCOR 15-Oct-25 07:00 17-Oct-25 17:00 2.42 Days
Continuous		 T4 (Poundmaker), 72PM25 (Poundmaker - Meadowlark), PM721 (Poundmaker) Poundmaker: TX4 Tap Changer Sample Pipe Install  
ALTALINK 15-Oct-25 07:00 18-Oct-25 18:00 3.46 Days
Continuous		 935L (324s Cassils - 356s Milo) Performing mtce. between Structures #53 - 148  
ATCO 15-Oct-25 09:30 16-Oct-25 17:30 1.33 Days
Continuous		 801s 905 (801s Anderson) breaker minimum oil HLR partial testing  
ATCO, ALTALINK 19-Oct-25 07:00 24-Oct-25 18:00 5.46 Days
Continuous		 923L (356s Milo - 2075s Newell) Performing mtce. between Structures #74 - 162  
EPCOR 20-Oct-25 07:00 24-Oct-25 17:00 4.42 Days
Continuous		 805s T3 (805s Jasper), EP 805s J2404 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: TX3 Zone Relay Maintenance  
ALTALINK 20-Oct-25 07:00 25-Oct-25 18:00 5.46 Days
Continuous		 944L (132s Ware Junction - 275s Jenner) Modifying existing structure 944L156 from a tangent assembly to a floating DE/phase raise configuration to tap onto a new adjacent substation. See also SAP: 294514 951L RB required due to proximity  
EPCOR, ALTALINK 20-Oct-25 07:00 26-Oct-25 17:00 6.42 Days
Continuous		 240BA2 (629s Argyll Transfer Station - 814s Bellamy), 1056L (89s Ellerslie - 629s Argyll Transfer Station), 814s B2402 (814s Bellamy), 814s B2401 (814s Bellamy) 240BA2 Zone: ADS1 LCR, Bellamy Transducer and DFR Cutovers, Bellamy 240kV SF6 Gas Tests and Leak Checks  
ALTALINK, EPCOR 20-Oct-25 09:30 26-Oct-25 17:30 6.33 Days
Continuous		 1056L (89s Ellerslie - 629s Argyll Transfer Station) 240BA2 Zone: ADS1 LCR, Bellamy Transducer and DFR Cutovers, Bellamy 240kV SF6 Gas Tests and Leak Checks  
ATCO 20-Oct-25 12:00 23-Oct-25 17:00 3.21 Days
Continuous		 951s SVC (951s Thickwood) Semi Annual inspection & maintenance  
ALTALINK 20-Oct-25 14:00 23-Oct-25 16:00 3.08 Days
Continuous		 612L (336s Fincastle - 368s Burdett), 368s 612 (368s Burdett) Maintenance.  
ALTALINK 21-Oct-25 07:00 24-Oct-25 18:00 3.46 Days
Continuous		 777L (48s Pocaterra - 245s Seebe) Replacement of 48s CTs (CT#3) associated with the 777L .Cts located on the line side of 48s below note 12 AB-BC
ATCO, CNRL 22-Oct-25 08:00 29-Oct-25 16:00 7.33 Days
Continuous		 838s 75-TR-1801 (838s Horizon Mining) 260kV Transformer Relay Upgrade  
ALTALINK 23-Oct-25 08:00 23-Oct-25 18:00 10 Hours
Continuous		 678s 850 (678s Okotoks), 850L (525s Carseland - 678s Okotoks) Major SCADA Upgrade Project. Cutting over supervisory controls to breaker and recloser to new RIO.  
ALTALINK 24-Oct-25 08:00 24-Oct-25 13:00 5 Hours
Daily		 44s T1 (44s Bearspaw Plant), 44s T2 (44s Bearspaw Plant) Outage required to remove PCB Lighting fixture located within LOA.  
EPCOR, ALTALINK 27-Oct-25 07:00 02-Nov-25 16:00 6.42 Days
Continuous		 240BA3 (629s Argyll Transfer Station - 814s Bellamy), 814s B2406 (814s Bellamy), 814s B2407 (814s Bellamy), 1055L (629s Argyll Transfer Station - 816s Petrolia) 240BA3 Zone: ADS2 LCR, Bellamy Transducer and DFR Cutovers, Bellamy 240kV SF6 Gas Tests and Leak Checks  
ATCO, ALTALINK 27-Oct-25 07:00 06-Nov-25 18:00 10.5 Days
Continuous		 1036L (356s Milo - 554s Travers) Installing interphase spacers and repairing the inner of the conductor (STR 5-45)  
ALTALINK 27-Oct-25 12:00 30-Oct-25 16:00 3.17 Days
Continuous		 899s 749N (899s Edgerton), 749L (899s Edgerton - 7LB749 tap) Replace 749LN A21/L8 LZ921 protection.  
ALTALINK 27-Oct-25 12:00 31-Oct-25 18:00 4.25 Days
Continuous		 749L (899s Edgerton - 7LB749 tap) Component replacement from 749L338 - 749L463  
ALTALINK, TRANSALTA 29-Oct-25 10:00 29-Oct-25 14:00 4 Hours
Daily		 250p T1 (250p Bighorn Plant) maintenance  
ALTALINK 30-Oct-25 08:00 30-Oct-25 17:30 9.5 Hours
Daily		 17s 12 (17s Benalto) 17s12 PRC005 brk maint + first trip  
ALTALINK, TRANSALTA 30-Oct-25 10:00 30-Oct-25 14:00 4 Hours
Daily		 250p T2 (250p Bighorn Plant) maintenance  
EPCOR 03-Nov-25 07:00 09-Nov-25 17:00 6.42 Days
Continuous		 814s T1 (814s Bellamy), 814s B2401 (814s Bellamy), 814s B2407 (814s Bellamy), BR721 (Rossdale) Bellamy: TX1 Bushing Replacement and 240kv SF6 Gas Tests and Leak Checks  
ALTALINK, Lethbridge 03-Nov-25 08:00 03-Nov-25 17:00 9 Hours
Continuous		 667L (146s MacDonald - 370s North Lethbridge), 146s 667 (146s Macdonald) 146s667L Open End Outage required to add CT circuit into new SEL DDR. Test DDR Recording and commission . Require Protection outages on 667L "A" Protection relay (SEL 311L) , "B" Protection relay (GE L90), "352" Breaker Protection relays Redundant Protections will be in service at all times

  
ALTALINK, Lethbridge 03-Nov-25 08:00 03-Nov-25 17:00 9 Hours
Daily		 667L (146s MacDonald - 370s North Lethbridge) 146s667L Open End Outage required to add CT circuit into new SEL DDR. Test DDR Recording and commission . .  
Syncrude 03-Nov-25 08:00 10-Nov-25 16:00 7.33 Days
Continuous		 222 (Aurora), 222A (Aurora), 222B (Aurora), 223 (Aurora), 223A (Aurora), 223B (Aurora), D05 514 (D05), D05 511 (D05), D05 511A (D05), D05 511B (D05), D05 512 (D05), D05 512A (D05), D05 512B (D05) SCL - Complete D05 Substation, Zone 3 260kV PM  
Syncrude 03-Nov-25 08:00 13-Nov-25 16:00 10.33 Days
Continuous		 UE-1 (D05 - UE-1 Syncrude Plant 30-2), T1 (D05 Syncrude), D05 511 (D05), D05 519 (D05), D05 71 (D05), D05 71A (D05), D05 71B (D05), D05 80 (D05), D05 80B (D05), D05 79 (D05), D05 79B (D05), D05 73 (D05), D05 73A (D05), D05 73B (D05), D05 75 (D05), D05 75A (D05), LCF (D05), ML-4 (D05), UE-1 7206 (UE-1 Syncrude Plant 30-2), UE-1 72-16 (UE-1 Syncrude Plant 30-2) complete 6-Year 72 kV A bus preventive maintenance in D05 substation  
ATCO 03-Nov-25 09:00 10-Nov-25 16:00 7.29 Days
Continuous		 7L45 (798s Bridge Creek - 813s Little Smoky) Pole replacement line to ground issue ( Line raise )  
ALTALINK 03-Nov-25 14:00 04-Nov-25 17:30 27.5 Hours
Continuous		 39s 26 (39s Bickerdike) First trip & breaker maintenance on 39s26  
ENMAX, ALTALINK 04-Nov-25 08:00 05-Nov-25 16:00 1.33 Days
Continuous		 7.82L (42s Sarcee - SS-7) Replace connection point on shield wire weld tabs on structure  
ENMAX, ALTALINK 04-Nov-25 08:00 05-Nov-25 16:00 1.33 Days
Continuous		 7.82L (42s Sarcee - SS-7) Replace connection point on shield wire weld tabs on structure  
ATCO 04-Nov-25 09:00 04-Nov-25 16:00 7 Hours
Continuous		 822s 701 (822s Wolf Lake), 7L587 (822s Wolf Lake - 826s Marguerite Lake) Inspect CT wiring at RTXP test switch
Replace RTXP Test switch if no issue found with wiring terminations
Recommission affected test switch (Burden, logic testing)		  
ALTALINK, CascadeP 05-Nov-25 08:00 05-Nov-25 18:00 10 Hours
Daily		 39s 26 (39s Bickerdike), 39s 29 (39s Bickerdike), 1135L (39s Bickerdike - 1047s Whisky Jack) First trip & breaker maintenance on 39s29. Repair 39s28.  
ALTALINK 05-Nov-25 17:00 06-Nov-25 18:00 25 Hours
Continuous		 39s 29 (39s Bickerdike) Breaker maintenance on 39s29  
Syncrude 11-Nov-25 08:00 18-Nov-25 16:00 7.33 Days
Continuous		 D05 512 (D05), D05 512A (D05), D05 512B (D05), D05 513 (D05), D05 513A (D05), D05 513B (D05), D05 515 (D05) SCL - D05 Substation Zone 4 260kV PM with isolation of RL-2.  
ALTALINK 13-Nov-25 08:00 13-Nov-25 18:00 10 Hours
Daily		 1005AL (991s Little Bow - 1005L tap), 1005L (120s Picture Butte - 1005AL tap), 1005L (356s Milo - 1005AL tap) Modifying 1005L85A and creating Open Point 'A' on the 356s Milo side of 1005L85A  
ATCO 13-Nov-25 09:00 13-Nov-25 17:00 8 Hours
Continuous		 834s 903 (834s Wesley Creek) 903 B Phase Counter Replacement at 834s Wesley Creek  
ALTALINK 13-Nov-25 18:00 24-Nov-25 12:00 10.75 Days
Continuous		 1005L (356s Milo - 1005AL tap) Repairing the inner between STR 3-75 on 1005L  
EPCOR 17-Nov-25 07:00 23-Nov-25 17:00 6.42 Days
Continuous		 814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy), 814s T2 (814s Bellamy), BR722 (Rossdale) Bellamy: TX2 Bushing Replacement and 240kv SF6 Gas Tests and Leak Checks  
ENMAX 17-Nov-25 08:00 17-Nov-25 18:00 10 Hours
Continuous		 162B240-RB131 (SS-162), 162B240-RB132 (SS-162), 1-GSU-XF-0001 (SS-162) HV SW Maint. 162SW133, 162SW132.  
ALTALINK 17-Nov-25 08:30 20-Nov-25 16:30 3.33 Days
Continuous		 913L (69s North Barrhead - 732s Mitsue) Protection upgrade. Remove old protection, cut over to new protection and cut over equipment status, control and alarms to new station controller.  
ATCO 17-Nov-25 09:00 20-Nov-25 16:00 3.29 Days
Continuous		 732s 903 (732s Mitsue), 732s 904 (732s Mitsue), 9L913 (69s North Barrhead - 732s Mitsue) Protection upgrade. Remove old protection, cut over to new protection and cut over equipment status, control and alarms to new station controller.  
ATCO 17-Nov-25 10:00 24-Nov-25 16:00 7.25 Days
Continuous		 7L106 (834s Wesley Creek - 905s Meikle) Soil around the tower footings has eroded ( Tower Replacement )  
ATCO 17-Nov-25 10:00 24-Nov-25 16:00 7.25 Days
Continuous		 7L131 (834s Wesley Creek - 905s Meikle) Soil around the tower footings has eroded ( Tower Replacement )  
ENMAX 18-Nov-25 08:00 18-Nov-25 16:00 8 Hours
Continuous		 162B240-RB135 (SS-162), 162B240-RB134 (SS-162), 2-GSU-XF-0002 (SS-162) HV SW Maint. 162SW143, 162SW142. Schedule with CEC outage spring 2026  
ATCO 21-Nov-25 09:00 24-Nov-25 16:00 3.29 Days
Continuous		 732s 904 (732s Mitsue), 732s 906 (732s Mitsue), 9L56 (720s Wabasca - 732s Mitsue) Protection upgrade. Remove old protection, cut over to new protection and cut over equipment status, control and alarms to new station controller.  
ENMAX, ALTALINK 21-Nov-25 18:00 23-Nov-25 08:00 1.58 Days
Continuous		 936L (5s East Calgary - 102s Langdon) Crew working in vicinity of 937L  
ENMAX, ALTALINK 21-Nov-25 18:00 23-Nov-25 08:00 1.58 Days
Continuous		 937L (5s East Calgary - 102s Langdon) Reconductor between str 15 to 18 on both Circuits for line Clearance Mitigation  
ENMAX, ALTALINK 21-Nov-25 18:00 23-Nov-25 08:00 1.58 Days
Continuous		 936L (5s East Calgary - 102s Langdon) Crew working in vicinity of 937L  
ENMAX, ALTALINK 21-Nov-25 18:00 23-Nov-25 08:00 1.58 Days
Continuous		 936L (5s East Calgary - 102s Langdon) Reconductor between str 15 to 18 on both Circuits for line Clearance Mitigation  
ALTALINK, EPCOR 24-Nov-25 07:00 28-Nov-25 17:00 4.42 Days
Continuous		 1044L (EP 805s Jasper - 816s Petrolia), 816s P2405 (816s Petrolia), 816s P2406 (816s Petrolia) 1044L: Petrolia 1044L CT LCR  
EPCOR 24-Nov-25 07:00 30-Nov-25 17:00 6.42 Days
Continuous		 EP 803s T3 (EP 803s Lambton), EP 803s L721 (EP 803s Lambton), 72LH8 (EP 803s Lambton - EP Hardisty), 72LS24 (EP 803s Lambton - Strathcona) Lambton/LH8/LS24: LDS11 and LDS12 LCR  
ENMAX, ALTALINK 24-Nov-25 07:00 02-Dec-25 12:00 8.21 Days
Continuous		 832L (SS-10 - SS-12), 10.1TR (SS-10), 10MD138-10.1TR (SS-10) 10.1TR 'S' protection replacement. Trip test 10B138-832L. Protection operation 10MD138-10.1TR.  
ALTALINK 24-Nov-25 12:00 24-Nov-25 18:00 6 Hours
Daily		 1005AL (991s Little Bow - 1005L tap), 1005L (120s Picture Butte - 1005AL tap), 1005L (356s Milo - 1005AL tap) Modifying 1005L85A and closing Open Point 'A' and creating Open Point 'B' on the 120s Picture Butte side of 1005L85A  
ALTALINK 24-Nov-25 18:00 04-Dec-25 08:30 9.6 Days
Continuous		 1005L (120s Picture Butte - 1005AL tap) Completing maintenance on 1005L (STR 88-228)  
ALTALINK 26-Nov-25 23:00 27-Nov-25 03:00 4 Hours
Continuous		 62s T1 (62s Brazeau Plant) maintenance  
ALTALINK 27-Nov-25 03:00 27-Nov-25 07:00 4 Hours
Daily		 62s T2 (62s Brazeau Plant) maintenance  
ENMAX, ALTALINK 28-Nov-25 18:00 30-Nov-25 08:00 1.58 Days
Continuous		 936L (5s East Calgary - 102s Langdon) Reconductor between str 15 to 18 on both Circuits for line Clearance Mitigation  
ENMAX, ALTALINK 28-Nov-25 18:00 30-Nov-25 08:00 1.58 Days
Continuous		 937L (5s East Calgary - 102s Langdon) Crew working in vicinity of 936L  
ENMAX, ALTALINK 28-Nov-25 18:00 30-Nov-25 08:00 1.58 Days
Continuous		 937L (5s East Calgary - 102s Langdon) Crew working in vicinity of 936L  
ENMAX, ALTALINK 28-Nov-25 18:00 30-Nov-25 08:00 1.58 Days
Continuous		 936L (5s East Calgary - 102s Langdon) Reconductor between str 15 to 18 on both Circuits for line Clearance Mitigation  
ATCO 01-Dec-25 13:00 05-Dec-25 17:00 4.17 Days
Continuous		 732s 901 (732s Mitsue), 732s 902 (732s Mitsue), 9L40 (732s Mitsue - 809s Louise Creek) 240kV Bus and 144kV Breaker Fail Protection upgrade + Scada Upgrade.
Cutover 901, 902, and 9L40 to new Scada system, including end to ends with SOC.		  
ENMAX, ALTALINK 02-Dec-25 13:00 11-Dec-25 09:00 8.83 Days
Continuous		 693L (42s Sarcee - SS-10), 10.2TR (SS-10), 10MD138-10.2TR (SS-10) 10.2TR 'S' protection replacement. Trip test 10B138-693L. Protection operation 10MD138-10.2TR.  
ATCO 04-Dec-25 08:00 05-Dec-25 16:00 1.33 Days
Continuous		 7L32 (811s Clairmont Lake - 862s South Bezanson) TCM Pole replacement structure 1  
ALTALINK 04-Dec-25 08:30 04-Dec-25 15:00 6.5 Hours
Daily		 1005AL (991s Little Bow - 1005L tap), 1005L (120s Picture Butte - 1005AL tap), 1005L (356s Milo - 1005AL tap) Closing Open point 'B'  
ATCO 08-Dec-25 10:00 15-Dec-25 16:00 7.25 Days
Continuous		 9L40 (732s Mitsue - 809s Louise Creek) Replace 4 damaged poles ( Need winter access) Structures 221, 286, 299 and 304  
ALTALINK 09-Dec-25 07:00 12-Dec-25 17:30 3.44 Days
Continuous		 38s 7252 (38s East Edmonton) Replace Koncar CTs associated with 38s7252  
ENMAX, ALTALINK 11-Dec-25 09:00 11-Dec-25 15:00 6 Hours
Continuous		 832L (SS-10 - SS-12), 10.1TR (SS-10), Protection & Control (SS-10), 10MD138-10.1TR (SS-10) Trip testing 10BA8-10.1TR, 10BB8-10.1TR, 10B138-832  
ALTALINK, TRANSALTA 17-Dec-25 10:00 17-Dec-25 14:00 4 Hours
Daily		 250p T1 (250p Bighorn Plant) maintenance  
ALTALINK, TRANSALTA 18-Dec-25 10:00 18-Dec-25 14:00 4 Hours
Daily		 250p T2 (250p Bighorn Plant) maintenance  
ATCO 12-Jan-26 13:00 21-Jan-26 09:00 8.83 Days
Continuous		 9L57 (939s Livock - 960s Birchwood Creek) 9L57 Line to Ground Clearance Mitigation  
ATCO 26-Jan-26 13:00 04-Feb-26 09:00 8.83 Days
Continuous		 9L57 (939s Livock - 960s Birchwood Creek) 9L57 Line to Ground Clearance Mitigation  
ATCO 09-Feb-26 13:00 18-Feb-26 09:00 8.83 Days
Continuous		 9L57 (939s Livock - 960s Birchwood Creek) 9L57 Line to Ground Clearance Mitigation  
ATCO 17-Feb-26 09:00 03-Mar-26 17:00 14.33 Days
Continuous		 972s 240kV Bus 900BS1 (972s Tinchebray) Install Breaker 904 and 904CT
On release leave Bkr 904, 904A/904B closed as feed through (disable bkr trips), Bkr 901 still protecting 9L93		  
ATCO 23-Feb-26 13:00 04-Mar-26 09:00 8.83 Days
Continuous		 9L57 (939s Livock - 960s Birchwood Creek) 9L57 Line to Ground Clearance Mitigation  
SUNCOR 02-Mar-26 08:00 08-Mar-26 20:00 6.46 Days
Continuous		 29PL9-16 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT418/29PL9-16 SYSTEM;PM 5y,10y
  
ALTALINK 03-Mar-26 07:00 09-Mar-26 17:00 6.38 Days
Continuous		 944L (132s Ware Junction - 275s Jenner) Line outage to replace line protection relays at 132s Ware Junction, replace relay comm cards and update settings on line protections at 275s Jenner and implement third terminal 1080s Jurassic line protection relays. End to end testing between all three sites.  
SUNCOR 09-Mar-26 08:00 15-Mar-26 20:00 6.5 Days
Continuous		 29PL9-17 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT419/29PL9-17 SYSTEM;PM 5y,10y
  
ATCO 09-Mar-26 13:00 18-Mar-26 09:00 8.83 Days
Continuous		 9L57 (939s Livock - 960s Birchwood Creek) 9L57 Line to Ground Clearance Mitigation  
ATCO 10-Mar-26 09:00 14-Apr-26 17:00 35.33 Days
Continuous		 972s 240kV Bus 900BS2 (972s Tinchebray) Install Breakers 905/906, 905CT/906CT, switches 905A/906B
On release leave Bkrs 905/906, 905A/905B, and 906A/906B closed as feed through (disable bkr trips), Bkr 903 still protecting 9L93, leave new 9L62D1 open for future line connection		  
ATCO, SUNCOR 16-Mar-26 08:00 22-Mar-26 20:00 6.5 Days
Continuous		 29PL9-1 (29EDD-1 Millennium - 848s Ruth Lake) 29EDD1;29CVT-3 SYSTEM;PM 5y,10y
  
ATCO, SUNCOR 23-Mar-26 08:00 29-Mar-26 20:00 6.5 Days
Continuous		 29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake) 29EDD1;29CVT-1 SYSTEM;PM 5y,10y  
ATCO, SUNCOR 30-Mar-26 08:00 05-Apr-26 20:00 6.5 Days
Continuous		 6L32 (29EDD-1 Millennium - 737s ATC Horseshoe) 29EDD1;29CVT-6 SYSTEM;5y,10y
  
ENMAX, ALTALINK 04-Apr-26 08:00 04-Apr-26 18:00 10 Hours
Continuous		 1003L (74s Janet - SS-25) Surge Arrestor Power Factor Test - 25MD240-1003  
ENMAX, ALTALINK 04-Apr-26 08:00 04-Apr-26 18:00 10 Hours
Continuous		 1003L (74s Janet - SS-25) Surge Arrestor Power Factor Test - 25MD240-1003  
ENMAX, ALTALINK 05-Apr-26 08:00 05-Apr-26 18:00 10 Hours
Continuous		 985L (74s Janet - SS-25) Surge Arrestor Power Factor Test - 25MD240-985  
ENMAX, ALTALINK 05-Apr-26 08:00 05-Apr-26 18:00 10 Hours
Continuous		 985L (74s Janet - SS-25) Surge Arrestor Power Factor Test - 25MD240-985  
SUNCOR 06-Apr-26 08:00 12-Apr-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;
 
ENMAX 06-Apr-26 08:00 14-Apr-26 16:00 8.33 Days
Continuous		 65.2TR (SS-65) Tap Changer Inspection - 65.2-TC  
SUNCOR 13-Apr-26 08:00 19-Apr-26 20:00 6.5 Days
Continuous		 29EDD-1 T1 (29EDD-1 Millennium), 29EDD-1 260kV South Bus 1 (29EDD-1 Millennium), 29EDD-1 72kV South Bus (29EDD-1 Millennium) 29EDD1;XFMR T1; X260B1; X72B1 SYSTEM;PM 5y  
SUNCOR 20-Apr-26 08:00 26-Apr-26 20:00 6.5 Days
Continuous		 29EDD-1 T2 (29EDD-1 Millennium), 29EDD-1 260kV North Bus 2 (29EDD-1 Millennium), 29EDD-1 72kV North Bus (29EDD-1 Millennium) 29EDD1;XFMR T2; N260B2; N72B1 SYSTEM;PM 5y  
ATCO 21-Apr-26 09:00 26-Apr-26 17:00 5.33 Days
Continuous		 9LA93 (973s Lanes Lake - 9L93 tap) Cutover and commission 9L93 protection ccts from Bkrs 901/903 to Bkrs 904/905
**AESO NEEDS TO ADD 9L93, 973S 9LA93D1**
  
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.  
ATCO 05-May-26 09:00 06-May-26 17:00 1.33 Days
Continuous		 972s 240kV Bus 900BS1 (972s Tinchebray) Connect new 907B to 900BS1
  
ATCO 07-May-26 09:00 08-May-26 17:00 1.33 Days
Continuous		 972s 240kV Bus 900BS2 (972s Tinchebray) Connect new 909A to 900BS2  
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, ATCO 11-May-26 07:00 14-May-26 18:00 3.46 Days
Continuous		 72s T2 (72s Leismer), 72s 144kV Bus (72s Leismer), 7L114 (72s Leismer - 7LA114 tap) Transformer maintenance, doble, install Coresense & Qualitrol  
ALTALINK, ATCO 11-May-26 07:00 14-May-26 18:00 3.46 Days
Continuous		 72s 114 (72s Leismer), 7L114 (72s Leismer - 7LA114 tap) Customer maintenance  
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
  
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.
  
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.
  
ATCO 02-Jun-26 09:00 13-Jun-26 17:00 11.33 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		  
ATCO 14-Jun-26 09:00 25-Jun-26 17:00 11.33 Days
Continuous		 9L62 (972s Tinchebray - 87s Gaetz) Work on parallel line 9L86  
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 06-Jul-26 10:00 27-Nov-26 16:00 144.29 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 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 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, 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  
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  
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  
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 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  
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  
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 09-Feb-27 09:00 11-Feb-27 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 24-Feb-27 09:00 25-Feb-27 17:00 1.33 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 26-Feb-27 09:00 27-Feb-27 17:00 1.33 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 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		  
ATCO 16-Mar-27 09:00 18-Mar-27 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 from Pakenham to Big Mountain		  
ATCO 26-Mar-27 09:00 29-Mar-27 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 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		  
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		  
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  
ATCO 20-Jul-27 08:00 21-Jul-27 17:00 1.38 Days
Continuous		 7L53 (706s Irish Creek - 7LA53 tap), 7LA53 (969s Lindbergh - 7L53 tap), 7L53 (700s Bonnyville - 7LA53 tap) Cold Lake Area Project to connect 1064s  
ATCO 22-Jul-27 08:00 25-Jul-27 17:00 3.38 Days
Continuous		 7L91 (715s Leming Lake - 826s Marguerite Lake) Cold Lake Area Energy Centre Project
  
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  
ALTALINK 08-Nov-27 08:30 11-Nov-27 17:30 3.38 Days
Continuous		 409s 110 (409s Shell Scotford) Install new Deadend corner structure on ALC02L  
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.  

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: 2025-08-20   16:35:32


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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