Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2026-06-20

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
ATCO 25-Nov-25 17:46 18-Sep-26 18:00 7,127.23 Hours
Continuous		 876s 901T (876s Brintnell) forced outage oil leaking  
SUNCOR 04-Jan-26 08:00 02-Sep-26 16:00 5,791 Hours
Continuous		 29EDD-34 260kV Bus 29PP-45 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34), 29EDD-34 29PS-216 (29EDD-34) urgent repairs on 29PT-224 at 29EDD34 on 29PP-45 bus  
BHE Canada 22-Mar-26 13:00 30-Jun-26 17:00 2,404 Hours
Continuous		 120s C1 (120s Picture Butte), 120s C2 (120s Picture Butte) forced outage  
ATCO 08-Jun-26 00:00 29-Jun-26 23:59 527.98 Hours
Continuous		 9L45 (856s Kinosis - 2049s Kettle River) forced outage  
ALTALINK, ATCO 08-Jun-26 08:00 25-Jun-26 10:00 514 Hours
Continuous		 87s 240kV East Bus (87s Gaetz), 9L62 (87s Gaetz - 972s Tinchebray), 962L (87s Gaetz - 972s Tinchebray), 986L (87s Gaetz - 972s Tinchebray), 9L86 (87s Gaetz - 972s Tinchebray), 87s T2 (87s Gaetz), 87s 1252 (87s Gaetz), 87s 1652 (87s Gaetz), 87s 1552 (87s Gaetz), 87s 1952 (87s Gaetz), 87s 34 (87s Gaetz) completing all telecom work & protection testing with ATCO  
SUNCOR 08-Jun-26 09:00 21-Jun-26 20:00 323 Hours
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
  
ATCO, ALTALINK 13-Jun-26 17:01 25-Jun-26 17:00 272 Hours
Continuous		 9L62 (87s Gaetz - 972s Tinchebray) Work on parallel line 9L86  
EPCOR 15-Jun-26 07:00 24-Jul-26 17:00 946 Hours
Continuous		 EP 805s J2403 (EP 805s Jasper) Jasper: J2403 Replacement LCR  
ALTALINK 15-Jun-26 07:30 25-Jun-26 09:30 242 Hours
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) P&C Upgrade (37s76, 37s82)  
ALTALINK, EPCOR 15-Jun-26 09:00 20-Jun-26 17:30 127.5 Hours
Continuous		 1139L (367s Harry Smith - EP Riverview) Riverview: 1139L Zone Doble and RWDS6/RWDS9/RWSA12 Disconnect Maintenance and RW2403/RW2405 (SF6) Breaker Maintenance  
ATCO, CNRL 15-Jun-26 09:00 29-Jun-26 10:00 337 Hours
Continuous		 859s 701T (859s Primrose), 859s 701 (859s Primrose), 859s 701TD (859s Primrose), 859s 704 (859s Primrose) maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 20-Jun-26 17:00 127.5 Hours
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  
ATCO 16-Jun-26 09:00 25-Jun-26 17:00 224 Hours
Continuous		 972s 902 (972s Tinchebray), 972s 903 (972s Tinchebray) connect new 9L86 to 972S and prepare to energize, complete protection commissioning  
EPCOR 17-Jun-26 07:00 24-Jun-26 17:00 178 Hours
Continuous		 987s GT3 (987s Clover Bar), 987s CGB3 (987s Clover Bar) maintenance  
BCH 19-Jun-26 09:00 25-Jun-26 17:00 152 Hours
Continuous		 2L294 (BCH A. A. Lambert - BCH Cranbrook) maintenance AB-BC
ENMAX, ALTALINK 20-Jun-26 08:00 20-Jun-26 18:00 10 Hours
Continuous		 832L (SS-10 - SS-12), 12.1TR (SS-12) Substation Structure Painting  
ALTALINK 21-Jun-26 07:30 30-Jun-26 09:30 218 Hours
Continuous		 77s 29 (77s Sagitawah) Protection upgrade (77s29)  
ENMAX 21-Jun-26 08:00 21-Jun-26 18:00 10 Hours
Continuous		 162.2TR (SS-162), 138kV South Bus (SS-162), 240kV South Bus (SS-162) Summer Substation Washing  
ENMAX, ALTALINK 21-Jun-26 08:00 21-Jun-26 18:00 10 Hours
Continuous		 833L (SS-2 - SS-12), 12.2TR (SS-12) Substation Structure Painting  
EPCOR 22-Jun-26 07:00 25-Jun-26 17:00 82 Hours
Continuous		 987s GT1 (987s Clover Bar) maintenance  
ENMAX, ALTALINK 22-Jun-26 07:30 22-Jun-26 16:30 9 Hours
Continuous		 918L (281s Johnson - SS-162) Summer Substation Washing. 86-BF-918 Relays, Lockout Testing  
ENMAX, ALTALINK 22-Jun-26 08:00 22-Jun-26 16:00 8 Hours
Continuous		 162B240-RB133 (SS-162), 918L (281s Johnson - SS-162), 162B240-RB132 (SS-162) Summer Substation Washing. 86-BF-918 Relays, Lockout Testing  
ENMAX, ALTALINK 22-Jun-26 08:00 26-Jun-26 16:00 104 Hours
Continuous		 21.80L (42s Sarcee - SS-21), 21B138-21.80 (SS-21) Transmission tower climbing inspection  
SUNCOR 22-Jun-26 08:00 28-Jun-26 20:00 156 Hours
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 17:00 152 Hours
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  
SUNCOR 22-Jun-26 09:00 05-Jul-26 20:00 323 Hours
Continuous		 29EDD-34 29PT-340 (29EDD-34) 29EDD34;29PT-340 SYSTEM;PM 5y,10y; 29EDD34;29PP-102 SYSTEM;PM 5y,10y
  
ALTALINK, EPCOR 22-Jun-26 09:30 27-Jun-26 17:00 127.5 Hours
Continuous		 921L (71s Lamoureux - 987s Clover Bar), 987s C2404 (987s Clover Bar), 987s C2406 (987s Clover Bar) 921L/Cloverbar: CT/CVT/SA Doble and CDS30/CDS32/CDS40 Disconnect Maintenance and C2404 (Min Oil) Breaker Maintenance and C2404/C2406 Capacitor Nameplate Pictures and C2401 Relay Maintenance  
ALTALINK, EPCOR 22-Jun-26 09:30 27-Jun-26 17:00 127.5 Hours
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 17:00 151.5 Hours
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 50 Hours
Continuous		 2029s ACF11 (2029s Heathfield), 2029s 1218 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF11
PRC-005 - TRIP COIL TESTING - BREAKER 1218 @ 2029S		  
ALTALINK 22-Jun-26 10:30 24-Jun-26 17:00 54.5 Hours
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), 320p 90 (320p Keephills) 320p91 PRC5 Breaker Maintenance and 320p213 Switch repair. Test 320p1352 CTs.  
ENMAX, ALTALINK 23-Jun-26 07:30 23-Jun-26 16:30 9 Hours
Continuous		 932L (74s Janet - SS-162) Summer Substation Washing. 86-BF-932 Relays, Lockout Testing  
ENMAX, ALTALINK 23-Jun-26 08:00 23-Jun-26 16:00 8 Hours
Continuous		 932L (74s Janet - SS-162), 162B240-RB136 (SS-162), 162B240-RB135 (SS-162) Summer Substation Washing. 86-BF-932 Relays, Lockout Testing  
ALTALINK 23-Jun-26 08:00 23-Jun-26 17:00 9 Hours
Continuous		 163s 1352 (163s Amoco Empress) 163s1352, Nitrogen Top up.  
ALTALINK 24-Jun-26 07:00 24-Jun-26 18:00 11 Hours
Continuous		 1046L (310p Sundance - 338s Cherhill) GOI on 1046L for a high load move  
ENMAX, ALTALINK 24-Jun-26 08:00 24-Jun-26 16:00 8 Hours
Continuous		 162B138-RB80 (SS-162), 162B138-RB81 (SS-162), 162.81L (391s Balzac - SS-162) Summer Substation Washing  
ALTALINK 24-Jun-26 08:00 24-Jun-26 16:30 8.5 Hours
Continuous		 391s 162.81 (391s Balzac) Summer Substation Washing  
ALTALINK 24-Jun-26 09:30 24-Jun-26 16:30 7 Hours
Continuous		 338s 552 (338s Cherhill) 240kV breaker maintenance  
ATCO 24-Jun-26 13:00 26-Jun-26 17:30 52.5 Hours
Continuous		 2029s ACF21 (2029s Heathfield), 2029s 1222 (2029s Heathfield) FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF21
PRC-005 - TRIP COIL TESTING - BREAKER 1222 @ 2029S		  
EPCOR, ALTALINK 25-Jun-26 07:00 10-Jul-26 17:00 370 Hours
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  
ALTALINK 25-Jun-26 07:15 25-Jun-26 17:45 10.5 Hours
Continuous		 1112L (89s Ellerslie - 289s Saunders Lake) transmission line maintenance  
ATCO 25-Jun-26 09:00 25-Jun-26 17:00 8 Hours
Continuous		 7L08 (830s Carmon - 834s Wesley Creek), 830s 701T (830s Carmon), 830s 701TCS (830s Carmon) planned outage to change out double D.E arm at Str 99 outside Carmon substation  
ALTALINK 28-Jun-26 06:00 28-Jun-26 13:00 7 Hours
Continuous		 77s 40 (77s Sagitawah) trip test 77s40  
ENMAX 28-Jun-26 08:00 28-Jun-26 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 Structure Painting  
ALTALINK, ENMAX 28-Jun-26 08:00 28-Jun-26 19:00 11 Hours
Continuous		 44s 36.81E (44s Bearspaw Plant), 36.81L (44s Bearspaw Plant - SS-36) Substation Structure Painting  
ALTALINK 28-Jun-26 11:00 28-Jun-26 18:00 7 Hours
Continuous		 77s 57 (77s Sagitawah) trip test 77s57  
SUNCOR 29-Jun-26 08:00 02-Jul-26 19:00 83 Hours
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 30-Jun-26 08:00 30-Jun-26 18:00 10 Hours
Continuous		 77s 26 (77s Sagitawah) trip test 77s26  
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
Daily		 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  
ENMAX 01-Jul-26 08:00 01-Jul-26 18:00 10 Hours
Continuous		 162.1TR (SS-162), 240kV North Bus (SS-162), 138kV North Bus (SS-162) Summer Substation Washing  
ATCO 02-Jul-26 08:00 02-Jul-26 17:00 9 Hours
Continuous		 7L04 (ATC 793s West Peace River - 839s Daishowa), 839s 701T (839s Daishowa Plant), 839s 701 (839s Daishowa) Replace Station Service Secondary Conductors at 839s Daishowa
PRC-005 - SPR TESTING - TRANSFORMER 701T @ 839S
PRC-005 - TRIP COIL TESTING - BREAKER 701 @ 839S		  
ATCO 02-Jul-26 09:00 03-Jul-26 17:30 32.5 Hours
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		  
ALTALINK 06-Jul-26 06:30 15-Jul-26 09:30 219 Hours
Continuous		 77s 57 (77s Sagitawah) Protection upgrade 77s57  
EPCOR 06-Jul-26 07:00 12-Jul-26 17:00 154 Hours
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  
ENMAX 06-Jul-26 08:00 06-Jul-26 12:00 4 Hours
Continuous		 65B240-D130 (SS-65) HV Breaker SF6 Gas Sample - 65B240-D130  
ALTALINK 06-Jul-26 08:00 09-Jul-26 17:00 81 Hours
Continuous		 310p 1152 (310p Sundance) Replace 310p1152 CTs  
ATCO, GREENGATEP 06-Jul-26 09:00 09-Jul-26 17:00 80 Hours
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 17:30 104.5 Hours
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 75.5 Hours
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 17:30 103.5 Hours
Continuous		 2029s ACF22 (2029s Heathfield), 2029s 1223 (2029s Heathfield) PRC-005 - TRIP COIL TESTING - BREAKER 1223 @ 2029S
BREAKER SF6 3AP4FI MAINTENANCE - 1223 @ 2029S
ACF22 Breaker low SF6 (breaker 1223) @2029S Heathfield
FILTER BANK AC MAINTENANCE @ HEATHFIELD 2029S ACF22		  
ENMAX 06-Jul-26 12:00 06-Jul-26 16:00 4 Hours
Continuous		 65B240-D131 (SS-65) HV Breaker SF6 Gas Sample - 65B240-D131  
ALTALINK 06-Jul-26 13:00 09-Jul-26 16:00 75 Hours
Continuous		 385s T3 (385s Spring Coulee) 385sT3 filter install and tap changer investigation.  
ALTALINK 06-Jul-26 13:30 09-Jul-26 17:00 75.5 Hours
Continuous		 320p 2652 (320p Keephills), 320p 2752 (320p Keephills), 320p PS2 (320p Keephills) 320sPS2 PRC5 Maintenance & Leak Repairs  
ALTALINK 07-Jul-26 07:30 07-Jul-26 12:00 4.5 Hours
Continuous		 927L (102s Langdon - 356s Milo), 102s 6652 (102s Langdon), 102s 6552 (102s Langdon), 356s 927 (356s Milo) CT cutovers to new DLR protections LTO testing to RAS protections  
ENMAX 07-Jul-26 08:00 07-Jul-26 12:00 4 Hours
Continuous		 65B240-D132 (SS-65) HV Breaker SF6 Gas Sample - 65B240-D132  
ENMAX 07-Jul-26 12:00 07-Jul-26 16:00 4 Hours
Continuous		 65B240-D133 (SS-65) HV Breaker SF6 Gas Sample - 65B240-D133  
ALTALINK 07-Jul-26 12:01 07-Jul-26 16:00 3.98 Hours
Continuous		 924L (102s Langdon - 356s Milo), 102s 6952 (102s Langdon), 102s 6852 (102s Langdon), 356s 924 (356s Milo) CT cutovers to new DLR protections LTO testing to RAS protections  
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  
BCH 08-Jul-26 09:00 08-Jul-26 17:00 8 Hours
Continuous		 5L91 (BCH Ashton Creek - BCH Selkirk) maintenance AB-BC
ATCO 08-Jul-26 10:00 09-Jul-26 16:00 30 Hours
Continuous		 825s 902 (825s Whitefish Lake) BREAKER MAINTENANCE  
ALTALINK 09-Jul-26 07:00 09-Jul-26 18:00 11 Hours
Continuous		 1140L (89s Ellerslie - 289s Saunders Lake) Replacing insulators on structure 36  
ATCO 09-Jul-26 13:01 09-Jul-26 15:00 1.98 Hours
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. Remove birds nest  
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 20:00 156 Hours
Continuous		 29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake), 29EDD-1 29EDD1s152 (29EDD-1 Millennium) 29EDD1;29CVT-1 SYSTEM;PM 5y,10y  
ALTALINK 13-Jul-26 06:30 13-Jul-26 12:29 5.98 Hours
Continuous		 77s 29 (77s Sagitawah) trip test 77s29  
EPCOR 13-Jul-26 07:00 19-Jul-26 17:00 154 Hours
Continuous		 EP 803s L2401 (EP 803s Lambton) Lambton: L2401 (Min Oil) Breaker Maintenance and CT Doble  
ALTALINK 13-Jul-26 08:00 14-Jul-26 16:30 32.5 Hours
Continuous		 205s 14 (205s Castle Rock Ridge) maintenance.  
ATCO 13-Jul-26 09:00 24-Jul-26 17:30 272.5 Hours
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), 2075s 917 (2075s Newell), 2075s 918 (2075s Newell) SVC NEWELL MAINTENANCE - SVC1 @ 2075S
SEMI-ANNUAL SVC VALVE COOLING MAINTENANCE @ NEWELL 2075S SVC1		  
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 13-Jul-26 12:30 13-Jul-26 18:00 5.5 Hours
Continuous		 77s 40 (77s Sagitawah) trip test 77s40  
ALTALINK 14-Jul-26 07:00 14-Jul-26 13:00 6 Hours
Continuous		 562s 1452 (562s Cypress), 562s 1652 (562s Cypress), 658L (562s Cypress - 658AL tap), 658L (649s Chappice Lake - 658AL tap) Replacing insulator on structure 306  
ALTALINK 14-Jul-26 09:00 15-Jul-26 14:00 29 Hours
Continuous		 214s 443 (214s Innisfail), 55s 443 (55S Olds), 443L (55s Olds - 214s Innisfail), 287s 552 (287s Hazelwood) Create Open Point 'D', Connect 475s mobile  
ALTALINK 14-Jul-26 09:30 23-Jul-26 11:00 217.5 Hours
Continuous		 163s T5 (163s Amoco Empress) 163sT5 maintenance and oil leaks.  
ALTALINK 15-Jul-26 07:30 16-Jul-26 16:00 32.5 Hours
Continuous		 205s 13 (205s Castle Rock Ridge) Two Day outage required for Castle Ridge planned maintenance  
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 19-Jul-26 20:00 156 Hours
Continuous		 29EDD-1 29EDD1s452 (29EDD-1 Millennium) 29EDD1; 29EDD1;29EDD1S452 MAINT&TEST;PM 10Y  
SUNCOR 15-Jul-26 08:00 25-Jul-26 20:00 252 Hours
Continuous		 29EDD-2 29PT-3 (29EDD-2 Tar Island), 29PL6-22 (29EDD-1 Millennium - 29EDD-2 Tar Island) 29EDD2;29PT-3, 29PL6-22 SYSTEM;PM 5y,10y
  
ALTALINK 15-Jul-26 08:30 15-Jul-26 16:30 8 Hours
Continuous		 77s 54 (77s Sagitawah) trip test 77s54  
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 15-Jul-26 14:00 05-Oct-26 09:00 1,963 Hours
Continuous		 55s 417 (55S Olds), 55s T1 (55s Olds), 55s T2 (55s Olds), 417L (55s Olds - 281s Johnson), 287s 552 (287s Hazelwood) Mobile install at 55s for P_C major upgrade. Repair/replace s80, s83, s84. Salvage s51.  
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 20:00 156 Hours
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
  
ALTALINK, EPCOR 20-Jul-26 07:00 23-Jul-26 17:00 82 Hours
Continuous		 1057L (89s Ellerslie - 657s Summerside), 657s SU2401 (657s Summerside), 657s SU2402 (657s Summerside) 1057L/Summerside: CVT/Arrestor Doble, SUDS1/SUDS3/SUDS9 Disconnect Maintenance  
EPCOR 20-Jul-26 07:00 23-Jul-26 17:00 82 Hours
Continuous		 805s T3 (805s Jasper) Jasper: TX3, Tap Changer Investigation w/Vendor  
EPCOR 20-Jul-26 07:00 02-Aug-26 17:00 322 Hours
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  
ENMAX, ALTALINK 20-Jul-26 08:00 20-Jul-26 16:00 8 Hours
Continuous		 28.80L (42s Sarcee - SS-28), 28B138-28.80 (SS-28) HV Breaker Maintenance  
ALTALINK 20-Jul-26 08:00 21-Jul-26 17:00 33 Hours
Continuous		 310p 1252 (310p Sundance) Test 310p1252 CTs  
ALTALINK, TRANSALTA 20-Jul-26 08:00 23-Jul-26 17:00 81 Hours
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, GWPCORP 20-Jul-26 09:00 21-Jul-26 18:00 33 Hours
Continuous		 138s 2552 (138s Windy Flats), 603L (138s Windy Flats - 243s Soderglen) Job Scope: We need to complete maintenance on 243s138DS1  
ALTALINK, EPCOR 20-Jul-26 09:00 23-Jul-26 17:30 80.5 Hours
Continuous		 1057L (89s Ellerslie - 657s Summerside) 1057L/Summerside: CVT/Arrestor Doble, SUDS1/SUDS3/SUDS9 Disconnect Maintenance  
ATCO 20-Jul-26 10:00 21-Jul-26 15:00 29 Hours
Continuous		 804s 702 (804s Wintering Hills), 7L85 (804s Wintering Hills - 7LA85 tap) BREAKER SF6 GL312 TESTING - 702 @ 804S  
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 24-Jul-26 16:00 102 Hours
Continuous		 977s 901T (977s Salt Creek), 7L135 (820s Hangingstone - 977s Salt Creek) TRANSFORMER AND TAP CHANGER MAINTENANCE  
ALTALINK 20-Jul-26 14:30 07-Aug-26 17:00 434.5 Hours
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 33 Hours
Continuous		 7L65 (709s Vegreville - 7LA65 tap), 7L65 (710s Vermilion - 7LA65 tap), 7LA65 (708s Grizzly Bear - 7L65 tap) Switch Repairs, 7LA65D1  
SUNCOR 21-Jul-26 08:00 04-Aug-26 18:00 346 Hours
Continuous		 29EDD-63 29PT-179 (29EDD-63 Firebag Co-Gen), 29PL7-2 (29EDD-18 Firebag - 29EDD-63), 29EDD-63 30-252-11301 (29EDD-63), 29EDD-63 91-152-500201 (29EDD-63), 29EDD-18 29-752-105 (29EDD-18 Firebag), 29EDD-18 29-752-104 (29EDD-18 Firebag) FIREBAG: Replace air bladder on 29PT-179, test 29PT-179, and execute 29PT-179 T60 replacement  
ALTALINK 22-Jul-26 07:00 23-Jul-26 16:00 33 Hours
Continuous		 310p 1352 (310p Sundance) Test 310p1352 CTs  
Syncrude 22-Jul-26 08:00 10-Aug-26 16:00 464 Hours
Continuous		 Mildred T6 (Syncrude Mildred Lake), 635 (Syncrude Mildred Lake) SCL - repair tap changer in T6 transformer  
ATCO, OWF2 22-Jul-26 10:00 23-Jul-26 17:30 31.5 Hours
Continuous		 804s 703 (804s Wintering Hills), 7L153 (609s Wheatland - 804s Wintering Hills) BREAKER SF6 GL312 TESTING - 703 @ 804S  
ENMAX 23-Jul-26 08:00 23-Jul-26 12:00 4 Hours
Continuous		 65B240-D134 (SS-65) HV Breaker SF6 Gas Sample - 65B240-D134  
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  
ENMAX 23-Jul-26 12:00 23-Jul-26 16:00 4 Hours
Continuous		 65B240-D135 (SS-65) HV Breaker SF6 Gas Sample - 65B240-D135  
SUNCOR 25-Jul-26 08:00 31-Jul-26 20:00 156 Hours
Continuous		 29PL9-3 (29EDD-1 Millennium - 29EDD-3), 29EDD-3 29PT-6 (29EDD-3) 29EDD1;29CVT-4 SYSTEM;PM 5y,10y;
 
EPCOR 27-Jul-26 07:00 04-Sep-26 17:00 946 Hours
Continuous		 EP 805s J2401 (EP 805s Jasper) Jasper: J2401 Replacement LCR  
ALTALINK 27-Jul-26 08:00 28-Jul-26 17:00 33 Hours
Continuous		 310p 2152 (310p Sundance) Test 310p2152 CTs  
ALTALINK, TRANSALTA 27-Jul-26 08:00 30-Jul-26 17:00 81 Hours
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 18:00 105.5 Hours
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  
BCH 27-Jul-26 09:00 29-Jul-26 17:00 56 Hours
Continuous		 2L294 (BCH A. A. Lambert - BCH Nelway) maintenance AB-BC
ATCO 27-Jul-26 09:00 29-Jul-26 17:30 56.5 Hours
Continuous		 2029s 1301 (2029s Heathfield) DC HIGH SPEED SWITCH MAINTENANCE - 1301 @ 2029S
**EATL will need to run in P1 DMR Return while 1301 is out of service**		  
ALTALINK, EPCOR 27-Jul-26 09:30 31-Jul-26 17:00 103.5 Hours
Continuous		 909L (310p Sundance - 665s Dome), 665s D2403 (665s Dome) 909LW/Dome: CVT/SA Doble and DDS6/DDS7/DDS14 Disconnect Maintenance and D2403 Dashpot Repair and 909LW Relay Maintenance  
ATCO 27-Jul-26 10:00 29-Jul-26 16:00 54 Hours
Continuous		 848s 905 (848s Ruth Lake) BREAKER MAINTENANCE  
ATCO 27-Jul-26 10:00 31-Jul-26 17:30 103.5 Hours
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 32 Hours
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 07:00 30-Jul-26 16:00 33 Hours
Continuous		 310p 152 (310p Sundance) Test 310p152 CTs  
ALTALINK 29-Jul-26 07:00 30-Jul-26 17:00 34 Hours
Continuous		 254s 172E (254s Coaldale), 172L (254s Coaldale - 172EL tap) 172L str. 953,1000,1002,1004 Bonding and Grounding.  
ALTALINK 29-Jul-26 23:00 30-Jul-26 03:00 4 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  
ALTALINK 03-Aug-26 08:00 04-Aug-26 17:00 33 Hours
Continuous		 310p 1452 (310p Sundance) Test 310p1452 CTs  
ENMAX, ALTALINK 04-Aug-26 08:00 21-Aug-26 16:00 416 Hours
Continuous		 24.83L (74s Janet - SS-24) Wood pole installation  
ALTALINK, ENMAX 04-Aug-26 08:00 21-Aug-26 16:00 416 Hours
Continuous		 74s 24.83X (74s Janet), 24.83L (74s Janet - SS-24) Enmax Wood pole installation  
ENMAX, ALTALINK 04-Aug-26 09:00 04-Aug-26 17:00 8 Hours
Continuous		 5s T2 (5s East Calgary) Altalink outage. Altalink will be removing 5s T2 from service for maintenance  
ALTALINK, TRANSALTA 04-Aug-26 09:00 06-Aug-26 17:00 56 Hours
Continuous		 179s 733 (179s Gleichen), 428s 733X (428s Namaka), 733L (179s Gleichen - 428s Namaka) 733Lstr. 161-211 Crossarm work. Maintenance/repairs.  
ENMAX, ALTALINK 04-Aug-26 09:00 06-Aug-26 17:00 56 Hours
Continuous		 5s T2 (5s East Calgary) 5sT2 PRC Doble , Major Maint.  
ATCO 04-Aug-26 09:00 06-Aug-26 17:30 56.5 Hours
Continuous		 2029s 1301 (2029s Heathfield) DC HIGH SPEED SWITCH MAINTENANCE - 1302 @ 2029S
**EATL will need to run in P2 Return while 1302 is out of service		  
SUNCOR 04-Aug-26 09:00 07-Aug-26 20:00 83 Hours
Continuous		 29EDD-1 29EDD1s952 (29EDD-1 Millennium) 29EDD1s952 - Faulty SF6 Sensors / No visibility risk, No line outage - BPC-26-014 - 300677553  
BCH 04-Aug-26 09:00 23-Aug-26 13:00 460 Hours
Continuous		 5L91 (BCH Ashton Creek - BCH Selkirk) maintenance AB-BC
ALTALINK 04-Aug-26 10:00 05-Aug-26 16:30 30.5 Hours
Continuous		 74s 104 (74s Janet), 74s 103 (74s Janet), 74s 102 (74s Janet), 74s C3 (74s Janet), 74s C4 (74s Janet) 74s103 Major maint  
ATCO 04-Aug-26 10:00 06-Aug-26 16:00 54 Hours
Continuous		 848s 906 (848s Ruth Lake) BREAKER MAINTENANCE  
ATCO 04-Aug-26 10:00 18-Aug-26 17:30 343.5 Hours
Continuous		 930s Syn Condenser (930s Arcenciel) - Level 4 service / overhaul by ABB
- DFR replacement
  
ALTALINK 05-Aug-26 07:00 06-Aug-26 16:00 33 Hours
Continuous		 310p 2852 (310p Sundance) Test 310p2852 CTs  
ALTALINK 05-Aug-26 08:30 05-Aug-26 16:30 8 Hours
Continuous		 264s 352 (264s Elkwater) CT testing  
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 06-Aug-26 08:30 06-Aug-26 16:30 8 Hours
Continuous		 264s 452 (264s Elkwater) CT testing  
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.  
ALTALINK 07-Aug-26 08:30 07-Aug-26 16:30 8 Hours
Continuous		 264s 252 (264s Elkwater) CT testing  
SUNCOR 08-Aug-26 09:00 11-Aug-26 20:00 83 Hours
Continuous		 29EDD-1 29EDD1s852 (29EDD-1 Millennium) 29EDD1S852 Replace Densimeter  
ATCO 10-Aug-26 07:00 14-Aug-26 17:00 106 Hours
Continuous		 7L03 (749s Flyingshot Lake - 7L09 tap) Tie in of a bypass for 7L03 to facilitate Alberta highways construction project.  
EPCOR 10-Aug-26 07:00 16-Aug-26 17:00 154 Hours
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  
ALTALINK, EPCOR 10-Aug-26 08:00 10-Aug-26 16:00 9 Hours
Continuous		 1045L (EP 805s Jasper - 1045AL tap), 310p 1752 (310p Sundance), 310p 1652 (310p Sundance), 1045AL (320p Keephills - 1045L tap), 1045L (310p Sundance - 1045AL tap) Outage to create an 310P Open Point 'A' between 1045L and 310p16A & 310p17B to allow for T35 to remain energized during the 1852 CT replacement  
ATCO 10-Aug-26 09:00 13-Aug-26 16:00 79 Hours
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
  
ALTALINK, BCH 10-Aug-26 09:00 20-Aug-26 17:00 248 Hours
Continuous		 1L274 (48s Pocaterra - 978s BCH Britt Creek) maintenance AB-BC
ATCO, ALTALINK 10-Aug-26 09:30 11-Aug-26 17:30 32 Hours
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 79.5 Hours
Continuous		 702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 10-Aug-26 10:00 13-Aug-26 16:30 78.5 Hours
Continuous		 7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 10-Aug-26 10:00 14-Aug-26 17:30 103.5 Hours
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		  
ALTALINK 10-Aug-26 12:00 13-Aug-26 17:00 77 Hours
Continuous		 368s 612 (368s Burdett), 612L (336s Fincastle - 368s Burdett) 368s612 138kv Breaker CT Replacement  
ATCO 10-Aug-26 13:00 10-Aug-26 14:00 1 Hour
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 14:00 18-Aug-26 17:00 195 Hours
Continuous		 275s T1 (275s Jenner) Replace LV bushings, TC Maint, Cooper cutouts  
ATCO 10-Aug-26 14:01 10-Aug-26 15:00 0.98 Hours
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 1 Hour
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)  
ALTALINK 11-Aug-26 07:00 12-Aug-26 17:00 34 Hours
Continuous		 102s 552 (102s Langdon), 102s 252 (102s Langdon), 102s T4 (102s Langdon), 102s SVC (102s Langdon) To install a config change on the MACH controls from the controls system upgrade. During testing it was found some settings required changing. This is to implement those changes.  
ALTALINK 11-Aug-26 07:00 13-Aug-26 18:00 59 Hours
Continuous		 310p 1852 (310p Sundance) Replace 310p1852 CT's  
ATCO 11-Aug-26 10:00 11-Aug-26 11:00 1 Hour
Continuous		 939s 1206 (939s Livock) PRC-005 Trip Coil testing,  
ATCO 11-Aug-26 11:00 11-Aug-26 12:00 1 Hour
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 12:00 11-Aug-26 13:00 1 Hour
Continuous		 939s 1214 (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 1 Hour
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)  
SUNCOR 12-Aug-26 09:00 15-Aug-26 20:00 83 Hours
Continuous		 29EDD-1 29EDD1s1052 (29EDD-1 Millennium) 29EDD1S1052 Densimeter Replacement - No visibility outage, no line outage - BPC-26-017 - 300347749  
ATCO 12-Aug-26 09:30 13-Aug-26 17:30 32 Hours
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 54 Hours
Continuous		 848s 907 (848s Ruth Lake) BREAKER MAINTENANCE  
ALTALINK, EPCOR 14-Aug-26 07:00 14-Aug-26 16:00 9 Hours
Continuous		 1045AL (320p Keephills - 1045L tap), 1045L (310p Sundance - 1045AL tap), 1045L (EP 805s Jasper - 1045AL tap), 310p 1752 (310p Sundance), 310p 1652 (310p Sundance) Outage to close 310P Open Point 'A' between 1045L and 310p16A & 310p17B that allowed for T35 to remain energized during the 1852 CT replacement  
ALTALINK 14-Aug-26 07:00 14-Aug-26 17:00 10 Hours
Continuous		 83s 172W (83s Taber), 172L (83s Taber - 172EL tap) 172L938 Arm change on single pole tan  
ALTALINK, EPCOR 17-Aug-26 09:30 22-Aug-26 17:00 127.5 Hours
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 17:00 127.5 Hours
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 78.5 Hours
Continuous		 7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ALTALINK 17-Aug-26 10:00 20-Aug-26 16:30 78.5 Hours
Continuous		 702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ALTALINK 17-Aug-26 12:00 20-Aug-26 17:00 77 Hours
Continuous		 245s 777X (245s Seebe), 777L (48s Pocaterra - 245s Seebe) 245s777X 138kV CT testing AB-BC
ALTALINK 17-Aug-26 12:30 20-Aug-26 17:00 76.5 Hours
Continuous		 320p 652 (320p Keephills) Replace 320p652 external CT's  
ATCO 17-Aug-26 13:00 20-Aug-26 13:00 72 Hours
Continuous		 939s 903T (939s Livock), 939s 912 (939s Livock), 9L10 (876s Brintnell - 939s Livock) PRC-005 - SPR TESTING - TRANSFORMER 903T @ 939S
Repair and adjust 910A @ 939S APL
Repalce OLTC Filters on 903T @ 939s Livock
Kelman DGA failure, 903T @ 939S Livock		  
ALTALINK 17-Aug-26 14:00 20-Aug-26 16:30 74.5 Hours
Continuous		 574s T1 (574s Nilrem) Transformer maintenance  
ALTALINK, ATCO, FMGW 18-Aug-26 08:00 19-Aug-26 17:00 33 Hours
Continuous		 964AL (1024s Granlea - 964L tap), 1024s PT-6001 (1024s Granlea), 1024s PT-6002 (1024s Granlea), 1024s 952-600001 (1024s Granlea), 1024s PS-6005 (1024s Granlea), 1024s PS-6006 (1024s Granlea), 1024s PS-6007 (1024s Granlea), 1024s PS-6008 (1024s Granlea), 1024s 489-600201 (1024s Granlea) maintenance activities (testing and inspection) of electrical equipment  
EPCOR 24-Aug-26 07:00 30-Aug-26 17:00 154 Hours
Continuous		 557s T2 (557s Castle Downs), 557s CD2403 (557s Castle Downs), 557s CD2404 (557s Castle Downs), 557s CDAB2 (557s Castle Downs) Castledowns: TX2 tap changer and disconnect switch maintenance  
ALTALINK, BCH 24-Aug-26 08:00 01-Sep-26 17:00 201 Hours
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 17:00 201 Hours
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 17:00 201 Hours
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 17:00 201 Hours
Continuous		 MATL (120s Picture Butte - Montana) align with 1201L outage AB-MATL
ALTALINK, EPCOR 24-Aug-26 09:00 25-Aug-26 17:00 32 Hours
Continuous		 908AL (52S East Industrial - 908L tap), 52s T2 (52s East Industrial), 52s E2402 (52s East Industrial) East Industrial/908LW: CVT JB Rewiring  
ALTALINK 24-Aug-26 09:00 25-Aug-26 18:00 33 Hours
Continuous		 908L (38s East Edmonton - 908AL tap), 908L (89s Ellerslie - 908AL tap) East Industrial/908LW: CVT JB Rewiring  
ALTALINK 24-Aug-26 13:00 28-Aug-26 17:00 100 Hours
Continuous		 28s R1 (28s West Brooks) 28sR1 leak category 5, Doble R1
28s44 PRC5 (no first trip)		  
Syncrude 28-Aug-26 08:00 12-Sep-26 16:00 368 Hours
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 17:00 322 Hours
Continuous		 EP 803s T3 (EP 803s Lambton), EP 803s L2403 (EP 803s Lambton), EP 803s L2405 (EP 803s Lambton), EP 803s L721 (EP 803s Lambton), 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 17:30 104 Hours
Continuous		 801s 902 (801s Anderson) BREAKER MIN OIL HLR COMPLETE TESTING  
ATCO 31-Aug-26 10:00 03-Sep-26 16:00 78 Hours
Continuous		 826s 902T (826s Marguerite Lake) transformer maintenance  
EPCOR 07-Sep-26 07:00 11-Sep-26 17:00 106 Hours
Continuous		 987s GT2 (987s Clover Bar), 987s CGB2 (987s Clover Bar) Cloverbar:  
EPCOR 08-Sep-26 07:00 13-Sep-26 17:00 130 Hours
Continuous		 72PM25 (Poundmaker - Meadowlark), PM2402 (Poundmaker), PM2403 (Poundmaker), PM721 (Poundmaker), T4 (Poundmaker) Poundmaker: TX4 Doble  
EPCOR 08-Sep-26 07:00 23-Oct-26 17:00 1,090 Hours
Continuous		 805s T4 (805s Jasper), EP 805s J2405 (EP 805s Jasper), EP 805s J2406 (EP 805s Jasper) Jasper: J2406/JDS10 Replacement LCR  
ATCO 08-Sep-26 10:00 10-Dec-26 16:00 2,239 Hours
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 16:00 219 Hours
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 12:00 113 Hours
Continuous		 1141L (1172s Laramide - 237s Foothills) End to end testing with Laramide 1172s  
EPCOR 14-Sep-26 07:00 20-Sep-26 17:00 154 Hours
Continuous		 EP 803s L2402 (EP 803s Lambton) Lambton: L2402 (Min Oil) Breaker Maintenance and CT Doble  
EPCOR 14-Sep-26 07:00 21-Sep-26 17:00 178 Hours
Continuous		 987s GT3 (987s Clover Bar), 987s CGB3 (987s Clover Bar) Cloverbar:  
ALTALINK, EPCOR 14-Sep-26 09:30 17-Sep-26 17:00 79.5 Hours
Continuous		 920L (37s North Calder - 557s Castle Downs), 557s CD2401 (557s Castle Downs), 557s CD2403 (557s Castle Downs) 920LW/Castledowns: Surge Arrestor LCR  
ALTALINK, EPCOR 14-Sep-26 09:30 17-Sep-26 17:00 79.5 Hours
Continuous		 920L (37s North Calder - 557s Castle Downs) 920LW/Castledowns: Surge Arrestor LCR  
ATCO, ALTALINK 14-Sep-26 10:00 28-Sep-26 17:30 343.5 Hours
Continuous		 830L (562s Cypress - 840s McNeill Station), 840s 901T (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 17:30 224.5 Hours
Continuous		 618s 725 (618s Riverbend), 725AL (618s Riverbend - 725L tap), 725L (111s Coalbanks - 725AL tap), 725L (674s Bowron - 725AL tap) Outage required to replace 674s12-Disconnect Switch and 674sPT5-CVT  
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  
ALTALINK 17-Sep-26 08:00 17-Sep-26 12:30 4.5 Hours
Continuous		 33s 1 (33s Spray) blackstart testing  
ALTALINK 17-Sep-26 13:00 17-Sep-26 17:00 4 Hours
Continuous		 33s 2 (33s Spray) blackstart testing  
ATCO 21-Sep-26 10:00 24-Sep-26 16:00 78 Hours
Continuous		 888s 906 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
EPCOR 22-Sep-26 07:00 25-Sep-26 17:00 82 Hours
Continuous		 987s GT1 (987s Clover Bar), 987s SST2 (987s Clover Bar), 987s CS2 (987s Clover Bar), 987s CGB1 (987s Clover Bar), 987s CCP7214 (987s Clover Bar), 987s CC24 (987s Clover Bar), 987s CH724 (987s Clover Bar), 987s CK726 (987s Clover Bar), 987s 72kV Bus 4 (987s Clover Bar) Cloverbar: , SST2, BUS 4 Outage. CDS18 Disconnect Replacement  
ATCO 25-Sep-26 10:00 28-Sep-26 16:00 78 Hours
Continuous		 888s 905 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
ALTALINK 28-Sep-26 07:00 08-Oct-26 17:00 250 Hours
Continuous		 510s 2652 (510s Sunnybrook), 510s 2752 (510s Sunnybrook), AML 511s 4852 (AML 511s Crossings), AML 511s 4952 (AML 511s Crossings), 1325L (510s Sunnybrook - AML 511s Crossings) Annual Valve Hall Maintenance, PRC Tx Maintenance, Doble Testing of the Transformers, PRC Relay Maintenance, Annual Yard Inspections, TDC settings changes, VCS Maintenance  
ATCO 28-Sep-26 08:00 05-Oct-26 16:00 176 Hours
Continuous		 7L44 (749s Flyingshot Lake - 845s Big Mountain) Changing str 71,72,73 and 74 for high load move line raise  
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  
SUNCOR 28-Sep-26 09:00 04-Oct-26 20:00 155 Hours
Continuous		 29EDD-34 260kV Bus 29PP-45 (29EDD-34) 29EDD34 29PP45 A,C phase rebuild bus and supports that were removed as part of the 29PT-224 outage.

  
Lethbridge 28-Sep-26 09:00 15-Oct-26 17:00 416 Hours
Continuous		 674s 1 (674s Bowron), 725LW (674s Bowron - 725BL tap) Line outage required on 725LW at 674s to replace 674s1-Manual Airbreak Switch and replace 674s2 and 674s6 PT's  
ALTALINK, Lethbridge 28-Sep-26 14:05 15-Oct-26 18:05 412 Hours
Continuous		 725L (674s Bowron - 725BL tap) Lethbridge outage required to replace 674s1-Disconnect Switch, 674sPT4-CVT, 674sPTB2-3phase CVT's, new screw piles and structure for 674sPTB2-CVT's  
ALTALINK 29-Sep-26 08:00 29-Sep-26 18:00 10 Hours
Continuous		 1002L (163s Amoco Empress - 275s Jenner) 1002L - Replace top phase spacer on STR67
 
EPCOR 05-Oct-26 07:00 18-Oct-26 17:00 322 Hours
Continuous		 CV5 (EP 511s Victoria - 557s Castle Downs) CV5/TX5: Manhole Inspections and Maintenance and 72kV Breaker Fail Protection Upgrade Cutovers and Commissioning  
ALTALINK 05-Oct-26 08:30 28-Nov-26 06:30 1,295 Hours
Continuous		 62s 2 (62s Brazeau Plant) maintenence  
ATCO 05-Oct-26 10:00 08-Oct-26 16:00 78 Hours
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  
ALTALINK 08-Oct-26 07:00 08-Oct-26 18:00 11 Hours
Continuous		 61s 202X (61s Lodgepole), 62s 202 (62s Brazeau Plant), 202L (61s Lodgepole - 62s Brazeau Plant) Line Maintenance  
Syncrude 12-Oct-26 08:00 27-Oct-26 16:00 368 Hours
Continuous		 11A (Aurora), 21A (Aurora), 31A (Aurora), 89-210 (Aurora), 89-51 (Aurora), T1 (Aurora), 211A (Aurora), 221A (Aurora), 260kV Bus 1 (Aurora), 72 kV Bus 1 (Aurora) 6yr PM  
ATCO 12-Oct-26 10:00 15-Oct-26 16:00 78 Hours
Continuous		 888s 906 (888s Dover) 21A/9L74 relay replacement. Cutover breaker and CT to new protection  
ALTALINK 15-Oct-26 08:00 15-Oct-26 18:00 10 Hours
Continuous		 158s 763N (158s Vauxhall), 28s 47 (28s West Brooks), 28s 31 (28s West Brooks), 447s 763A (447s Enchant), 447s 16 (447s Enchant), 763AL (447s Enchant - 763A1L tap), 763L (158s Vauxhall - 763AL tap), 763L (28s West Brooks - 763AL tap) 447s27 Replace line VT. (Like for like replacement)  
ALTALINK, TRANSALTA, Lethbridge 15-Oct-26 17:10 15-Oct-26 21:00 3.83 Hours
Continuous		 15s 725 (15s Fort Macleod), 725BL (240s McBride Lake - 725L tap), 725L (15s Fort MacLeod - 725BL tap), 725L (674s Bowron - 725BL tap) to close 725L Open Point 'A' and restore 725L to normal  
ATCO 16-Oct-26 10:00 19-Oct-26 16:00 78 Hours
Continuous		 888s 905 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
ALTALINK 19-Oct-26 07:00 20-Oct-26 18:00 35 Hours
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 17:00 274 Hours
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 17:00 151.5 Hours
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 17:00 151.5 Hours
Continuous		 908L (89s Ellerslie - 816s Petrolia) Petrolia: 908LE Surge Arrestor and CVT LCR  
ALTALINK 21-Oct-26 08:00 22-Oct-26 17:00 33 Hours
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 17:00 106 Hours
Continuous		 909L (89s Ellerslie - 665s Dome), 665s D2401 (665s Dome), 665s D2404 (665s Dome), 72DS26 (665s Dome - Strathcona) 909LE/Dome: Dome CVT LCR and 909LE Metering Upgrade  
EPCOR 26-Oct-26 07:00 18-Dec-26 17:00 1,283 Hours
Continuous		 805s T3 (805s Jasper), EP 805s J2404 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: J2404/JAB3/JDS9 Replacement LCR  
ENMAX, ALTALINK 26-Oct-26 08:00 04-Nov-26 16:00 225 Hours
Continuous		 24.83L (74s Janet - SS-24) Steel pole installation  
ENMAX, ALTALINK 26-Oct-26 08:00 04-Nov-26 16:00 225 Hours
Continuous		 24.83L (74s Janet - SS-24), 74s 24.83X (74s Janet) Enmax Steel pole installation  
ATCO 26-Oct-26 08:00 13-Nov-26 17:00 442 Hours
Continuous		 806s 701T (806s Oldman River) Telecommunications Upgrade, new UPS upgrades.  
ALTALINK, EPCOR 26-Oct-26 09:00 30-Oct-26 17:30 104.5 Hours
Continuous		 89s 1052 (89s Ellerslie), 89s 1152 (89s Ellerslie), 909L (89s Ellerslie - 665s Dome) 909LE/Dome: Dome CVT LCR and 909LE Metering Upgrade  
ATCO 26-Oct-26 10:00 29-Oct-26 16:00 78 Hours
Continuous		 9L74 (888s Dover - 960s Birchwood Creek) 21B/9L74 relay three terminal line testing  
ATCO, ALTALINK 26-Oct-26 10:00 02-Nov-26 16:00 175 Hours
Continuous		 7L230 (69s North Barrhead - 888AL tap), 7L230 (743s Sarah Lake - 888AL tap) Replace 7L230D1 disconnect switch  
Syncrude 28-Oct-26 08:00 12-Nov-26 16:00 369 Hours
Continuous		 223 (Aurora), 222B (Aurora), 89-225 (Aurora), 223A (Aurora) G01 Zone 4 6yr PM  
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 80 Hours
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 17:00 274 Hours
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 17:00 778 Hours
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 17:00 778 Hours
Continuous		 PM2405 (Poundmaker) Poundmaker: P2405 Breaker Replacement  
ATCO 09-Nov-26 10:00 12-Nov-26 17:00 79 Hours
Continuous		 9L24 (946s Oakland - 959s Lanfine), 959s 906 (959s Lanfine), 959s 905 (959s Lanfine), 946s 902 (946s Oakland), 946s 903 (946s Oakland) Cutover Bkr/MOD status, Commission new LTO/RAS 204 A/B - Lanfine/Oakland  
ATCO 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 16-Nov-26 12:00 19-Nov-26 12:00 72 Hours
Continuous		 740s 705 (740s H.R. Milner), 7L80 (740s H.R. Milner - 857s Kakwa Ridge) PRC-005 - MICROPROCESSOR RELAY TESTING
TCM Program. RTXP Test Switch Mitigation and Replacement
Both RAS-A and RAS-B 7L80 will also need be OOS for the RTXP work on 21A and 21B 7L80		  
ATCO 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  
EPCOR 04-Dec-26 07:00 07-Dec-26 17:00 82 Hours
Continuous		 1055L (629s Argyll Transfer Station - 816s Petrolia), 240BA3 (629s Argyll Transfer Station - 814s Bellamy) 1055L/240BA3: ADS3 LCR Preparation Outage, jumpering out ADS2  
EPCOR, ALTALINK 07-Dec-26 17:00 14-Dec-26 17:00 168 Hours
Continuous		 240BA2 (629s Argyll Transfer Station - 814s Bellamy), 1056L (89s Ellerslie - 629s Argyll Transfer Station) 1056L/240BA2: ADS3 LCR (1055L and BA3 will be jumpered out and energized bypassing ADS2 for the duration of this outage)  
EPCOR 14-Dec-26 17:00 18-Dec-26 17:00 96 Hours
Continuous		 1055L (629s Argyll Transfer Station - 816s Petrolia), 240BA3 (629s Argyll Transfer Station - 814s Bellamy) 1055L/240BA3: ADS3 LCR Removing ADS2 jumper, restoring configuration  
ALTALINK 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 17:00 946 Hours
Continuous		 EP 805s J2405 (EP 805s Jasper) Jasper: J2405 Replacement LCR  
EPCOR 16-Feb-27 07:00 30-Mar-27 17:00 1,017 Hours
Continuous		 EP 805s J2407 (EP 805s Jasper) Jasper: J2407 Replacement LCR  
ALTALINK, EPCOR 19-Feb-27 07:00 05-Mar-27 17:00 346 Hours
Continuous		 1045L (EP 805s Jasper - 1045AL tap), EP 805s J2406 (EP 805s Jasper), EP 805s J2407 (EP 805s Jasper) 1045L/Jasper: J2407 Replacement LCR  
ALTALINK 19-Feb-27 07:00 05-Mar-27 18:00 347 Hours
Continuous		 1045AL (320p Keephills - 1045L tap), 1045L (310p Sundance - 1045AL tap) 1045L/Jasper: J2407 Replacement LCR  
ATCO 08-Mar-27 10:00 17-Mar-27 17:00 222 Hours
Continuous		 9L24 (946s Oakland - 959s Lanfine), 959s 906 (959s Lanfine), 959s 905 (959s Lanfine), 946s 902 (946s Oakland), 946s 903 (946s Oakland) Replace A/B protection relays at 959S Lanfine and 946S Oakland
Cut in and reroute 9L24
Connect new 9LA24 T-tap
Commission Telecom and Protection to new 1072S Rose Lynn substation		  
SUNCOR 05-Apr-27 09:00 11-Apr-27 20:00 155 Hours
Continuous		 29PL9-12 (29EDD-34 - 29EDD-65) 29EDD34;29PL9-12 SYSTEM;PM 5y,10y
  
SUNCOR 06-Apr-27 09:00 16-Apr-27 20:00 251 Hours
Continuous		 29EDD-34 29PT-112 (29EDD-34), 29EDD-34 29-752-121 (29EDD-34), 29EDD-34 29PS-68 (29EDD-34), 29EDD-34 29PS-67 (29EDD-34), 29EDD-34 29PS-66 (29EDD-34), 29EDD-34 29PS-65 (29EDD-34), 29EDD-34 29PS-225 (29EDD-34), 29EDD-34 29PS-230 (29EDD-34), 29EDD-34 29-952-141 (29EDD-34), 29EDD-34 29-952-131 (29EDD-34), 29EDD-34 29-952-111 (29EDD-34) 29EDD34;29PT-112 & 29PP-24 SYSTEM;PM
This will Place 29EDD-34 on one 260 kV bus and drop 29PL7-1 		 
ATCO 12-Apr-27 10:00 19-Apr-27 17:00 175 Hours
Continuous		 7L22 (790s Poplar Hill - 7L88 tap) Cut open 7L22, connect new line section to new 2061S Dobbs
7L22/21B relay upgrades at 790S Poplar Hill and 811S Clairmont Lake
On completion energize new 2061S Dobbs substation		  
SUNCOR 14-Apr-27 14:00 23-Apr-27 18:00 220 Hours
Continuous		 29EDD-65 29PT-0257 (29EDD-65), 29EDD-65 29-952-4812 (29EDD-65), 29EDD-65 29-952-4813 (29EDD-65), 29EDD-71 752-4624 (29EDD-71), 29EDD-71 752-4623 (29EDD-71), 29PL7-4 (29EDD-65 - 29EDD-71) Firebag: 29EDD65;29PT-257 & 29PL7-4 SYSTEM, 29EDD65 ;29PT-260 & 29PL7-4 SYSTEM, 29EDD71 29PT-241 & 29PL7-4  
ATCO 03-May-27 09:00 17-May-27 17:30 344.5 Hours
Continuous		 2075s T11 (2075s Newell) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 344.5 Hours
Continuous		 2029s T11 (2029s Heathfield) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 344.5 Hours
Continuous		 13L50 (2029s Heathfield - 2075s Newell) Annual EATL outage at 2075s & 2029s.
**1218 IS NOT THE ISOALTION. ATCO SENT AESO OF REQUIRED ISOLATIONS BACK IN MAY 2024 TO UPDATE 2029S AND 2075S ISOLATIONS FOR 13L50 OUTAGES**		  
ATCO 03-May-27 10:00 06-May-27 17:00 79 Hours
Continuous		 7L22 (811s Clairmont Lake - 7L88 tap) 7L22/21B relay upgrade at 811S Clairmont Lake
Upon completion new 2061S Dobbs substation ready to energize		  
SUNCOR 04-May-27 09:00 14-May-27 20:00 251 Hours
Continuous		 29EDD-34 29PS-214 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34), 29EDD-34 29PS-215 (29EDD-34), 29EDD-34 29PS-213 (29EDD-34) 29EDD34;29PL9-13 SYSTEM;PM 5y,10y  
SUNCOR 05-May-27 14:00 14-May-27 18:00 220 Hours
Continuous		 29EDD-65 29PT-0236 (29EDD-65), 29EDD-65 29-952-4823 (29EDD-65), 29EDD-65 29-952-4822 (29EDD-65), 29EDD-71 752-4634 (29EDD-71), 29EDD-71 752-4633 (29EDD-71), 29PL7-3 (29EDD-65 - 29EDD-71) Firebag: 29EDD65;29PT-236 & 29PL7-3 SYSTEM, 29EDD65;29PT-250&29PL7-3 SYSTEM, 29PT-246 SYSTEM;29EDD71  
ATCO 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 17:00 225 Hours
Continuous		 635EDD-1000 635-752-635PT-1000 (635EDD-1000), 635EDD-1000 635PT-1000 (635EDD-1000) FH - Maintenance on Transformer, associated breakers, other equipment in isolation boundary and protection system testing.  
SUNCOR 01-Jun-27 09:00 11-Jun-27 20:00 251 Hours
Continuous		 29EDD-94 407T (29EDD-94 Voyageur), 29EDD-94 29-952-9705 (29EDD-94 Voyageur), 29EDD-94 29PS-393 (29EDD-94 Voyageur), 29EDD-94 29PS-392 (29EDD-94 Voyageur), 29EDD-94 29-952-9704 (29EDD-94 Voyageur), 29EDD-94 29PS-400 (29EDD-94 Voyageur) 29EDD94;29PT-407 SYSTEM;PM 5y,10y  
SUNCOR 11-Jun-27 08:00 20-Jun-27 17:00 225 Hours
Continuous		 635EDD-1000 635-752-635PT-1001 (635EDD-1000), 635EDD-1000 635PT-1001 (635EDD-1000) FH - Maintenance on Transformer, associated breakers, other equipment in isolation boundary and protection system testing.  
SUNCOR 15-Jun-27 09:00 25-Jun-27 20:00 251 Hours
Continuous		 29EDD-94 406T (29EDD-94 Voyageur), 29EDD-94 29-952-9702 (29EDD-94 Voyageur), 29EDD-94 29PS-388 (29EDD-94 Voyageur), 29EDD-94 29PS-389 (29EDD-94 Voyageur), 29EDD-94 29PS-399 (29EDD-94 Voyageur) 29EDD94;29PT-406 SYSTEM;PM 5y,10y  
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 33 Hours
Continuous		 964AL (1024s Granlea - 964L tap), 1024s PT-6001 (1024s Granlea), 1024s PT-6002 (1024s Granlea), 1024s 952-600001 (1024s Granlea), 1024s PS-6005 (1024s Granlea), 1024s PS-6006 (1024s Granlea), 1024s PS-6007 (1024s Granlea), 1024s PS-6008 (1024s Granlea), 1024s 489-600201 (1024s Granlea) maintenance activities (testing and inspection) of electrical equipment  
ALTALINK, BCH 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous		 1201L (520s Bennett - BCH Cranbrook), Path 1 (AIES Islanding) annual maintenance AB-BC
ALTALINK, BHE 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous		 MATL (120s Picture Butte - Montana) align with 1201L outage AB-MATL
ALTALINK, BCH 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous		 48s 887X (48s Pocaterra), 887L (48s Pocaterra - 978s BCH Britt Creek) opened because 1201L is out of service . AB-BC
ALTALINK, BCH 23-Aug-27 07:00 03-Sep-27 17:00 274 Hours
Continuous		 799s 786W (799s Coleman), 786L (799s Coleman - BCH Natal) opened because 1201L is out of service. AB-BC
ATCO 08-Nov-27 09:00 11-Nov-27 17:00 80 Hours
Continuous		 ALC02L (409s Shell Scotford - 879s Upgrader) Install new Deadend corner structure on ALC02L  
ATCO 08-Nov-27 09:00 11-Nov-27 17:00 80 Hours
Continuous		 ALC01L (408s Air Liquide Scotford - 409s Shell Scotford) Install new Deadend corner structure on ALC02L.  
ATCO 08-Feb-28 09:00 10-Feb-28 17:00 56 Hours
Continuous		 7L228 (845s Big Mountain - 7L20 tap) AESO project P2716 - Install 7L228 bypass to facilitate the installation of new line switches for the new 7LA228 T-tap line connection to the new 2103S Pakenham substation
Open 7L228, replace structures 551 and 551A, connect bypass.		  
ATCO 06-Mar-28 10:00 22-Mar-28 16:00 389 Hours
Continuous		 826s 903 (826s Marguerite Lake), 826s 907 (826s Marguerite Lake), 826s 901T (826s Marguerite Lake) Expand 240kV ring bus for new 9L42 line  
ATCO 13-Mar-28 10:00 16-Mar-28 17:00 79 Hours
Continuous		 9L939 (77s Sagitawah - 809s Louise Creek) Cut over 9L939 to temp bypass structures to allow for installation of new deadend corner towers. These are required to make the final connections to the new 2105S Jackson substation  
ATCO 14-Mar-28 09:00 16-Mar-28 17:00 56 Hours
Continuous		 7L228 (845s Big Mountain - 7L20 tap) AESO project P2716 - Disconnect bypass, connect new 7LA228D1 to 7LA228 Str #2, connect 7L228 to 7L228D2, connect 7L228 to 7L228D3. Renumber existing line switches 7L228D2 - D4, 7L228D3 - D5, 7L228D4 - D6
Commission DTT		  
ATCO 17-Mar-28 10:00 17-Apr-28 17:00 751 Hours
Continuous		 9L938 (77s Sagitawah - 809s Louise Creek) Install foundations (TBD assume concrete), assemble and erect new Q-towers 9L938/9L939-155A and 9L938/9L939-156A in existing ROW centreline. Daily outage until such a time as the new towers begin to encroach on 9L938.  
ATCO 20-Mar-28 09:00 23-Mar-28 17:00 80 Hours
Continuous		 2091s 704 (2091s Thornton) AESO project P2716 - cut over new SEL 2440 wiring at 2091S, relay programming, commission DTT and LTO  
ATCO 24-Mar-28 09:00 27-Mar-28 17:00 80 Hours
Continuous		 740s 704 (740s H.R. Milner), 7L20 (740s H.R. Milner - 810s Dome Cutbank) AESO project P2716 - cut over RAS #171 wiring at 740S, relay programming, commission LTO 7L20/7L228  
ATCO 18-Apr-28 10:00 25-Apr-28 17:00 175 Hours
Continuous		 9L938 (77s Sagitawah - 809s Louise Creek) Open 9L938 conductors, complete assembly and connect to the new Q-Towers 9L938/9L939-155A and 9L938/9L939-156A, string to 2105S Jackson deadend and terminate.
Relabel 9L938 segment from 809S Louise Creek to 2105S Jackson to 9L140.		  
ATCO 01-May-28 10:00 04-May-28 17:00 79 Hours
Continuous		 9L939 (77s Sagitawah - 809s Louise Creek) Disconnect 9L939 conductors from temp structure 9L939 -155A - 155E reconnect to existing structures 9L938/9L939-156 and 9L938/9L939-155, connect to the new Q-Towers 9L938/9L939-155A and 9L938/9L939-156A, string to 2105S Jackson deadend and terminate.
Relabel 9L939 segment from 809S Louise Creek to 2		  
ATCO 08-May-28 09:00 10-Jul-28 17:00 1,520 Hours
Continuous		 959s 240kV Bus 900BS2 (959s Lanfine) GOI on 9L141 until line terminated into 1162S Fair Acres and ready to energize  
ATCO 08-May-28 09:00 10-Jul-28 17:00 1,520 Hours
Continuous		 959s 240kV Bus 900BS2 (959s Lanfine) GOI on 902/903 until line terminated and 1162S Fair Acres ready to energize  
ATCO 09-May-28 10:00 13-May-28 17:00 103 Hours
Continuous		 9L02 (809s Louise Creek - 813s Little Smoky) Install concrete foundations for new structures 9L02/320A, 320H in preparation to cut into 9L02 and convert to a t-tap.  
ATCO 15-May-28 09:00 17-May-28 17:00 56 Hours
Continuous		 959s 240kV Bus 900BS1 (959s Lanfine) Connect new bus from new 902B to existing switch 901A to add new line 9L141,
Cutover and commission 900PT1 ccts to new 9L141 relays		  
ATCO 18-May-28 09:00 20-May-28 17:00 56 Hours
Continuous		 959s 240kV Bus 900BS2 (959s Lanfine) Connect new bus from new Bkr 903 to existing switch 903B to add new line 9L141,
Cutover and commission 900PT2 ccts to new 9L141 relays		  
ATCO 29-May-28 09:00 08-Jun-28 17:00 248 Hours
Continuous		 9L24 (946s Oakland - 959s Lanfine) Cutover and commission 905/906 CT's, 9L24PT ccts to new RAS 241 SEL 451A/B relays @ 959S Lanfine and update relay settings for RAS 241 and SCADA inputs @946S Oakland.  
ATCO 19-Jun-28 10:00 30-Jun-28 16:00 270 Hours
Continuous		 9L20 (755s Cordel - 766s Nevis)
Install concrete foundations at 9L20 Structure 69 for new T-Tap connection		  
ATCO 26-Jun-28 10:00 10-Jul-28 17:00 343 Hours
Continuous		 9L02 (809s Louise Creek - 813s Little Smoky) Cut into 9L02 and connect new t-tap structures for 9LA02.
9L02-21A and 21B relay upgrades at 809S Louise Creek and 813S Little Smoky. Implement RAS
Energize new line 9LA02 and 884S Magpie substation		  
ATCO 31-Jul-28 10:00 15-Aug-28 16:00 366 Hours
Continuous		 766s 901 (766s Nevis), 9L20 (755s Cordel - 766s Nevis), 755s 906 (755s Cordel), 755s 901 (755s Cordel)
Cutover new 9L20 line section, terminate 9LA20 at customer substation. Install new line protection relays		  
ATCO, GREENGATEP 01-Oct-28 08:00 21-Oct-28 16:00 488 Hours
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		  
ATCO, GREENGATEP 22-Oct-28 08:00 20-Nov-28 16:00 705 Hours
Continuous		 972S 906, 972s 906 (972s Tinchebray) CETO project
Install 906 and 906CT

Commission 906 and 906CT

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

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

Prepared On: 2026-06-10   4:43:58 PM


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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