Alberta Electric System Operator
Long Range Significant Transmission Outages for the period of 24 months starting 2026-03-07

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 25-Jul-25 17:01 17-Apr-26 17:00 266 Days
Continuous
T2 (EP Riverview) bushing test failure (found during OE110184)  
SUNCOR 04-Jan-26 08:00 02-Sep-26 16:00 241.29 Days
Continuous
29EDD-34 260kV Bus 29PP-45 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34) urgent repairs on 29PT-224 at 29EDD34 on 29PP-45 bus  
EPCOR 23-Feb-26 07:00 23-Mar-26 07:00 27.96 Days
Continuous
805s T3 (805s Jasper) bushing change  
Syncrude 24-Feb-26 08:00 10-Mar-26 16:00 14.29 Days
Continuous
11 (Aurora), 12 (Aurora), 13 (Aurora), T3 (Aurora), UT1 (Aurora), 11A (Aurora), 11B (Aurora), 12A (Aurora), 12B (Aurora), 13A (Aurora), 13B (Aurora), 89-15 (Aurora), 89-16 (Aurora), G20 (Aurora) zone 6, 6 year PM  
ALTALINK 03-Mar-26 08:00 09-Mar-26 17:00 6.33 Days
Continuous
132s 51 (132s Ware Junction), 132s 47 (132s Ware Junction), 275s 5 (275s Jenner), 275s 2 (275s Jenner), 944L (132s Ware Junction - 275s Jenner) replace line relays at 132s Ware Junction, replace relay comm cards and update settings on protections at 275s Jenner,
implement third 944AL terminal, new 1080s Raptor line protection relays, 1080s Raptor and 944AL tap addition, close Open Point 'A'
 
ATCO 05-Mar-26 07:00 08-Mar-26 16:00 3.33 Days
Continuous
732s 9L913D1 (732s Mitsue) emergency, Changing white tag poles from Test & Treat ( Str 16,69 and 503 )  
ALTALINK 07-Mar-26 08:00 07-Mar-26 16:00 8 Hours
Continuous
33s 2 (33s Spray) maintenance  
ALTALINK 08-Mar-26 07:00 08-Mar-26 18:00 11 Hours
Daily
1072L (103s Goose Lake - 205s Castle Rock Ridge) South Crew will be doing component replacement on 1072L15  
ALTALINK, EPCOR 09-Mar-26 07:00 10-Mar-26 17:00 1.42 Days
Continuous
908L (89s Ellerslie - 816s Petrolia), 816s P2401 (816s Petrolia), 816s P2406 (816s Petrolia) Petrolia: 908L Relay Maintenance  
EPCOR 09-Mar-26 07:00 13-Mar-26 17:00 4.42 Days
Continuous
987s GT3 (987s Clover Bar) Repair  
ATCO 10-Mar-26 08:00 10-Mar-26 17:00 9 Hours
Continuous
7L63 (788s Hotchkiss - 7LA63 tap), 788s 703 (788s Hotchkiss) emergency changing rotten cross arm str 86 and str 1115  
ALTALINK 10-Mar-26 09:00 10-Mar-26 17:00 8 Hours
Continuous
310p 1752 (310p Sundance) PRC5 Breaker Maintenance  
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
 
EPCOR 11-Mar-26 07:00 11-Mar-26 17:00 10 Hours
Continuous
557s CD2401 (557s Castle Downs) Castledowns: CD2401 NAIT Student Substation Tour  
EPCOR 11-Mar-26 07:00 13-Mar-26 17:00 2.42 Days
Continuous
816s T2 (816s Petrolia), 816s P2404 (816s Petrolia), 816s P2405 (816s Petrolia) Petrolia: TX2 Relay Maintenance  
ALTALINK 11-Mar-26 09:30 11-Mar-26 16:00 6.5 Hours
Continuous
310p 2052 (310p Sundance) First Trip, PRC5 maint & 27 relay replacement  
ALTALINK 11-Mar-26 11:00 11-Mar-26 12:30 90 Mins
Continuous
347s 199W (347s AML Fox Creek) 347s199W 138kV CB Low Gas top up.  
ENMAX, ALTALINK 12-Mar-26 08:00 13-Mar-26 18:00 1.42 Days
Continuous
7.82L (42s Sarcee - SS-7) Replace connection point on shield wire weld tabs on structure  
ALTALINK, ENMAX 12-Mar-26 08:30 13-Mar-26 18:00 1.4 Days
Continuous
42s 7 (42s Sarcee), 7.82L (42s Sarcee - SS-7) Replace connection point on shield wire weld tabs on structure  
ALTALINK 12-Mar-26 09:30 12-Mar-26 16:00 6.5 Hours
Continuous
310p 552 (310p Sundance) First Trip & PRC5 Maint  
EPCOR 14-Mar-26 07:00 29-Mar-26 17:00 15.42 Days
Continuous
330p 1207 (330p Genesee), 330p 1204 (330p Genesee), 330p 1201 (330p Genesee), 330p 1210 (330p Genesee), 330p 1214 (330p Genesee), 330P 12TC1 (330p Genesee), 330p 500kV Bus 1 (330p Genesee), 330p 805 (330p Genesee) Genesee: 500kV BUS 1, POW Project Installation  
EPCOR 15-Mar-26 07:00 01-Apr-26 17:00 17.42 Days
Continuous
330p 12GT6D (330p Genesee), 330p 1211 (330p Genesee), 330p 1210 (330p Genesee) POW project installation  
EPCOR 16-Mar-26 07:00 16-Mar-26 17:00 10 Hours
Continuous
816s P2403 (816s Petrolia) Petrolia: P2403 Relay Maintenance  
ALTALINK, EPCOR 16-Mar-26 07:00 19-Mar-26 17:00 3.42 Days
Continuous
1058L (657s Summerside - EP 803s Lambton), EP 803s L2403 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton), 657s SU2403 (657s Summerside), 657s SU2404 (657s Summerside) 1058L: Lambton Surge Counter Install and Summerside SUDS10 Ice Shield Repair  
EPCOR 16-Mar-26 07:00 20-Mar-26 17:00 4.42 Days
Continuous
T2 (Poundmaker) Poundmaker: TX2 Bladder and Sample Pipe Repair  
EPCOR 16-Mar-26 07:00 20-Mar-26 17:00 4.42 Days
Continuous
665s T2 (665s Dome) Dome: TX2, Neutral Bar Move for Building Expansion (UGT)  
ALTALINK 16-Mar-26 07:00 25-Mar-26 18:00 9.46 Days
Continuous
87s 2352 (87s Gaetz), 87s 1652 (87s Gaetz), 87s T1 (87s Gaetz), 87s 240kV West Bus (87s Gaetz), 914L (63s Red Deer - 87s Gaetz) Installing new 87s1752 & 87s1952. Closing Open Points 'F', 'G', 'H'.  
EPCOR 16-Mar-26 07:00 01-Apr-26 17:00 16.42 Days
Continuous
987s GT1 (987s Clover Bar) maintenance  
ALTALINK 16-Mar-26 07:15 19-Mar-26 17:45 3.44 Days
Continuous
788L (898s Heart Lake - 788AL tap), 788L107A (788AL tap), 602L1 (602L tap) component replacement on 788L (STR 157 - 218)  
ENMAX 16-Mar-26 08:00 19-Mar-26 16:00 3.33 Days
Continuous
162.2TR (SS-162) Investigate tap changer oil leak. Oil Sampling MT, TC, Bushing. Relay Fault Pressure Test. Reversing Switch Check. Transformer Monitor Maintenance. Gas Monitor Maintenance. I&R Settings Issue on 162.2TR T60  
ALTALINK 16-Mar-26 08:00 19-Mar-26 16:00 3.33 Days
Continuous
788L (898s Heart Lake - 788AL tap) component replacement on 788L (STR 157 - 218)  
ALTALINK 16-Mar-26 09:00 16-Mar-26 13:00 4 Hours
Continuous
28s 47 (28s West Brooks), 28s 31 (28s West Brooks), 763L (28s West Brooks - 763AL tap) South crew will be doing general maintenance . The conductor damper on the top left phase. Str 147 ahead position, has run out about twenty feet.  
BCH 16-Mar-26 09:00 20-Mar-26 17:00 4.33 Days
Continuous
5L92 (BCH Cranbrook - BCH Selkirk) replace end of life spacers AB-BC
ALTALINK, Lethbridge 16-Mar-26 10:00 26-Mar-26 16:00 10.25 Days
Continuous
618s 824 (618s Riverbend), 824L (593s Lakeview - 618s Riverbend) City Of Lethbridge outage, Outage required to replace 593s1-Disconnect Switch and 593sPTL1-CVT.  
ALTALINK 16-Mar-26 12:00 20-Mar-26 12:00 4 Days
Continuous
163s 1752 (163s Amoco Empress), 163s 1552 (163s Amoco Empress), 1002L (163s Amoco Empress - 275s Jenner) Urgent Protection change, salvage old over voltage protections and incorporate overvoltage and RAS into 1002L Line protections.  
ATCO 17-Mar-26 09:00 17-Mar-26 11:00 2 Hours
Continuous
7L93 (828s Sulphur Point - 930s Arcenciel) Open end 7L93 at 930S to accommodate Telecom outage 1-00513974  
ALTALINK 17-Mar-26 09:30 17-Mar-26 11:30 2 Hours
Continuous
108s 352 (108s Amelia) PRC5 Breaker Maint & First Trip  
ALTALINK 17-Mar-26 09:30 17-Mar-26 16:00 6.5 Hours
Continuous
89s 2052 (89s Ellerslie) PRC5 Maint & First Trip  
ALTALINK 17-Mar-26 11:30 17-Mar-26 16:00 4.5 Hours
Continuous
574s 652 (574s Nilrem) PRC5 Maint & First Trip  
ALTALINK 17-Mar-26 13:30 17-Mar-26 16:00 2.5 Hours
Continuous
108s 452 (108s Amelia) PRC5 Breaker Maint & First Trip  
ALTALINK 18-Mar-26 08:00 19-Mar-26 17:00 1.38 Days
Continuous
163s 1752 (163s Amoco Empress), 163s 1552 (163s Amoco Empress), 1002L (163s Amoco Empress - 275s Jenner) South Crew will be doing component replacement on 1002L (STR 67-99)  
ALTALINK 18-Mar-26 08:30 18-Mar-26 17:00 8.5 Hours
Continuous
28s T1 (28s West Brooks) 28sT1 Out of step alarm.  
ALTALINK 18-Mar-26 09:00 18-Mar-26 11:30 2.5 Hours
Continuous
574s 452 (574s Nilrem) PRC5 Breaker Maint & First Trip  
ALTALINK 18-Mar-26 09:30 18-Mar-26 16:00 6.5 Hours
Continuous
108s 252 (108s Amelia) PRC5 Breaker Maint & First Trip

Repair local/remote cutoff switch
 
ALTALINK 18-Mar-26 10:00 18-Mar-26 16:00 6 Hours
Continuous
13s 1552 (13s Deerland), 13s 98 (13s Deerland), 1054L (12s Heartland - 13s Deerland) PRC5 Maint & First trip on 13s1552

13s98 Hot spot repair & switch adjustment
 
ALTALINK 18-Mar-26 13:30 18-Mar-26 16:00 2.5 Hours
Continuous
574s 552 (574s Nilrem) PRC5 Breaker Maint  
ALTALINK 19-Mar-26 08:00 28-Mar-26 16:00 9.33 Days
Continuous
132s 51 (132s Ware Junction), 132s 55 (132s Ware Junction), 28s 5 (28s West Brooks), 28s 8 (28s West Brooks), 931L (28s West Brooks - 132s Ware Junction) Urgent replacement of 28s 931L A - protection.  
ALTALINK 20-Mar-26 07:00 20-Mar-26 18:00 11 Hours
Continuous
908L (38s East Edmonton - 908AL tap), 908L (89s Ellerslie - 908AL tap) 908LW/East Industrial: EDS2 Repair/Adjustment  
ATCO 21-Mar-26 09:00 26-Mar-26 16:00 5.29 Days
Continuous
7L89 (721s La Corey - 826s Marguerite Lake) Replace 2 white tagged poles which failed test and trat inspection. 7L89 poles on structures 7L89/7L91-225 & 7L89/7L91-230  
EPCOR 23-Mar-26 07:00 27-Mar-26 17:00 4.42 Days
Continuous
805s T3 (805s Jasper), EP 805s J2405 (EP 805s Jasper), EP 805s J2404 (EP 805s Jasper) Jasper: TX3 Relay Maintenance and Scaffold Removal  
ALTALINK 23-Mar-26 07:30 26-Mar-26 16:00 3.35 Days
Continuous
AML 511s 1152 (AML 511s Crossings), AML 511s T30 (AML 511s Crossings) Firmware upgrades on protections that are OOS, VCS Maintenance, Annual SVC+ maintenance  
ENMAX, ALTALINK 23-Mar-26 08:00 23-Mar-26 12:00 4 Hours
Continuous
28.80L (42s Sarcee - SS-28) 1 sub Transmission line cut over.  
ENMAX 23-Mar-26 08:00 26-Mar-26 18:00 3.42 Days
Continuous
162.1TR (SS-162) Investigate tap changer oil leak. Oil Sampling MT, TC, Bushing. Relay Fault Pressure Test. Reversing Switch Check. Transformer Monitor Maintenance. Gas Monitor Maintenance. I&R Settings Issue on 162.1TR T60  
ALTALINK 23-Mar-26 08:00 01-Apr-26 16:00 9.33 Days
Continuous
347s 199W (347s AML Fox Creek) Breaker 347s199W breaker replacement.  
ALTALINK 23-Mar-26 12:00 26-Mar-26 16:00 3.17 Days
Continuous
430s 452 (430s Ursus) Replace 430s452 Breaker CTs.  
ALTALINK 23-Mar-26 14:00 24-Mar-26 16:00 26 Hours
Continuous
89s T2 (89s Ellerslie) Replace Oil level gauges & Modify qualitrol temps  
ALTALINK 23-Mar-26 14:00 26-Mar-26 16:00 3.08 Days
Continuous
310p 1852 (310p Sundance) 310s1852 240kV breaker maintenance  
BHE Canada 24-Mar-26 07:00 24-Mar-26 18:00 11 Hours
Continuous
MATL (120s Picture Butte - Montana), 120s MATL PST (120s Picture Butte), 120s 1052 (120s Picture Butte), 120s 1352 (120s Picture Butte) RTU replacement AB-MATL
ALTALINK 25-Mar-26 09:30 25-Mar-26 11:30 2 Hours
Continuous
320p 552 (320p Keephills) 320s552 Breaker Maintenance  
ALTALINK 25-Mar-26 10:00 25-Mar-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ENMAX 25-Mar-26 12:00 25-Mar-26 18:00 6 Hours
Continuous
23.80L (74s Janet - SS-23), 23.4TR (SS-23) Spring Substation Washing  
ALTALINK 25-Mar-26 13:30 25-Mar-26 16:00 2.5 Hours
Continuous
320p 152 (320p Keephills) 320s152 Breaker Maintenance  
ALTALINK 26-Mar-26 09:00 26-Mar-26 11:30 2.5 Hours
Continuous
63s 24 (63s Red Deer), 63s T1 (63s Red Deer) PRC5 Maint & First Trip  
ALTALINK 26-Mar-26 09:30 26-Mar-26 16:00 6.5 Hours
Continuous
320p 752 (320p Keephills) 320s752 Breaker Maintenance  
ALTALINK 26-Mar-26 10:00 26-Mar-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ALTALINK 26-Mar-26 13:30 26-Mar-26 16:00 2.5 Hours
Continuous
63s 25 (63s Red Deer), 63s T2 (63s Red Deer) PRC5 Maint & First Trip  
EPCOR 30-Mar-26 07:00 31-Mar-26 17:00 1.42 Days
Continuous
805s T1 (805s Jasper), 805s C1 (805s Jasper), EP 805s J2401 (EP 805s Jasper), EP 805s J2403 (EP 805s Jasper), EP 805s J2408 (EP 805s Jasper), EP 805s J724 (EP 805s Jasper), EP 805s J722 (EP 805s Jasper) Jasper: TX1, CAP BANK Relay Maintenance and JDS21 Repair  
EPCOR 30-Mar-26 07:00 02-Apr-26 17:00 3.42 Days
Continuous
987s T3 (987s Clover Bar), 987s C2407 (987s Clover Bar) Cloverbar: C2407 (SF6) Breaker Maintenance and TX3 Relay Maintenance  
ALTALINK 30-Mar-26 07:00 08-Apr-26 18:00 9.46 Days
Continuous
87s 2352 (87s Gaetz), 87s 1252 (87s Gaetz), 87s T2 (87s Gaetz), 87s 240kV East Bus (87s Gaetz), 914L (86s Bigstone - 87s Gaetz) Installing new 87s1352 & 87s1552. Closing Open points 'E', 'J', 'K' & 'L'. Creating permanent bus cut between 87s27 & 87s 240kV East Bus.  
ATCO 30-Mar-26 08:00 31-Mar-26 16:00 1.33 Days
Continuous
7L50 (757s Battle River - 491L tap) Replace structure 7L50-235  
ATCO, ALBIAN 30-Mar-26 09:00 31-Mar-26 15:00 30 Hours
Continuous
920s 901T (920s Jackpine) Isolation of 901T for CNRL to troubleshoot problems on their system  
ALTALINK 30-Mar-26 13:00 02-Apr-26 16:00 3.13 Days
Continuous
430s 652 (430s Ursus) 430s652 CT Replacement.  
ALTALINK 30-Mar-26 14:00 03-Apr-26 17:00 4.13 Days
Continuous
320p 1352 (320p Keephills) CT Replacement w/ RMH CTs associated w/ 320p1352 (CT13).  
ALTALINK 31-Mar-26 08:00 31-Mar-26 17:00 9 Hours
Continuous
428s 733N (428s Namaka), 733L (151s Strathmore - 428S Namaka) 428s733N 138kV CB Minor maintenance, First Trip PRC 5.  
ALTALINK, NOVACORP 01-Apr-26 08:00 02-Apr-26 18:00 1.42 Days
Continuous
330L1 (535s Joffre - 330s Nova Joffre) electrical equipment maintenance, corrective work, line OPGW fiber testing and PRC-005 testing  
ALTALINK 01-Apr-26 09:00 01-Apr-26 16:00 7 Hours
Continuous
428s 23 (428s Namaka) 428s23 PRC5 Minor Maintenance, First Trip  
ATCO, ALBIAN 01-Apr-26 09:00 02-Apr-26 15:00 30 Hours
Continuous
920s 902T (920s Jackpine) Isolation of 902T for CNRL to troubleshoot problems on their system  
ATCO 01-Apr-26 18:00 01-Apr-26 18:30 30 Mins
Continuous
7L199 (347s AML Fox Creek - 741s ATC Fox Creek) Altalink request ATCO to operate A741s 702 to facilitate 1st energization of of new 347s199W.  
ENMAX, ALTALINK 03-Apr-26 08:00 03-Apr-26 16:00 8 Hours
Continuous
36.81L (44s Bearspaw Plant - SS-36) Shield Wire Replacement  
ALTALINK, ENMAX 03-Apr-26 09:00 03-Apr-26 16:00 7 Hours
Continuous
44s 36.81E (44s Bearspaw Plant), 36.81L (44s Bearspaw Plant - SS-36) Shield Wire Replacement  
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  
ALTALINK 06-Apr-26 08:00 09-Apr-26 16:00 3.33 Days
Continuous
525s 850N (525s Carseland), 850L (525s Carseland - 678s Okotoks) 525s CT Replacement for 152 (850N) breaker  
SUNCOR 06-Apr-26 08:00 10-Apr-26 20:00 4.5 Days
Continuous
29EDD-94 29PP-97 260kV Bus (29EDD-94 Voyageur) 29EDD94, 29PT-412B Oil Leak (29PP-97 260KV outage) - Leak repair and top up (9001051293) TDEC  
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  
ALTALINK 06-Apr-26 13:00 09-Apr-26 17:00 3.17 Days
Continuous
430s 152 (430s Ursus) Replace 430s152 Breaker CTs  
EPCOR 07-Apr-26 07:00 10-Apr-26 17:00 3.42 Days
Continuous
T2 (EP Riverview), RW2402 (EP Riverview), RW2403 (EP Riverview) Riverview: TX2 Zone, Scaffold Removal  
Syncrude 08-Apr-26 08:00 20-Apr-26 16:00 12.33 Days
Continuous
Mildred T6 (Syncrude Mildred Lake), 6335 (Syncrude Mildred Lake), 634 (Syncrude Mildred Lake), 635 (Syncrude Mildred Lake) SCL - Repair Tap Changer in T6 Transformer.  
ALTALINK 09-Apr-26 08:30 09-Apr-26 16:00 7.5 Hours
Continuous
63s 752 (63s Red Deer) CT Testing - Doble, IDAX, DGA  
EPCOR 10-Apr-26 07:00 24-Apr-26 17:00 14.42 Days
Continuous
330p 1209 (330p Genesee), 330p 1206 (330p Genesee), 330p 1203 (330p Genesee), 330p 1211 (330p Genesee), 330p 1215 (330p Genesee), 330p 12TC2 (330p Genesee), 330p 809 (330p Genesee) Genesee: 500kV BUS 2, POW Project Installation  
EPCOR 11-Apr-26 07:00 25-Apr-26 17:00 14.42 Days
Continuous
330P GT7 (330p Genesee), 330p 1215 (330p Genesee), 330p 1214 (330p Genesee) POW project installation  
ALTALINK, EPCOR 13-Apr-26 07:00 17-Apr-26 17:00 4.42 Days
Continuous
947L (89s Ellerslie - 987s Clover Bar), 987s C2402 (987s Clover Bar), 987s C2404 (987s Clover Bar) Cloverbar: 947L Relay Maintenance  
ALTALINK 13-Apr-26 07:00 20-Apr-26 18:00 7.46 Days
Continuous
87s T1 (87s Gaetz), 87s 240kV West Bus (87s Gaetz), 914L (86s Bigstone - 87s Gaetz), 87s 2352 (87s Gaetz), 87s 1252 (87s Gaetz), 87s 1352 (87s Gaetz) Closing Open point 'I' and creating second permanent bus cut between 87s26 & 87s 240kV West Bus.  
EPCOR 13-Apr-26 07:00 29-May-26 17:00 46.42 Days
Continuous
805s T4 (805s Jasper) Jasper TX4: Bushing Change (PCB) and Fan Failure Repair and Conservator Tank Inspection and TX Re-gasketing  
ALTALINK 13-Apr-26 08:00 16-Apr-26 16:00 3.33 Days
Continuous
525s 851X (525s Carseland), 851L (253s Blackie - 525s Carseland) Replace 525s851X breaker CTs  
ATCO 13-Apr-26 10:00 17-Apr-26 16:00 4.25 Days
Continuous
951s SVC (951s Thickwood) Annual maintenance/inspection, software patching, password changes  
ALTALINK 13-Apr-26 12:00 16-Apr-26 16:00 3.17 Days
Continuous
430s 352 (430s Ursus) 430s352s CT Replacement.  
ATCO 14-Apr-26 07:00 17-Apr-26 13:00 3.25 Days
Continuous
7L101 (790s Poplar Hill - 944s Lowe Lake) maintenance  
ALTALINK 14-Apr-26 08:00 15-Apr-26 16:00 1.33 Days
Continuous
244s C1 (244s Bowmanton), 244s 752 (244s Bowmanton) Replace secondary control fuses in breaker control cabinet.
 
ALTALINK 14-Apr-26 08:00 15-Apr-26 16:00 1.33 Days
Continuous
244s C2 (244s Bowmanton), 244s 1052 (244s Bowmanton) Replace control fuses within breaker secondary cabinet

 
ALTALINK 14-Apr-26 08:00 15-Apr-26 16:00 1.33 Days
Continuous
244s C3 (244s Bowmanton), 244s 952 (244s Bowmanton) Replace secondary control fuses in breaker control cabinet.

 
ENMAX, ALTALINK 18-Apr-26 08:00 18-Apr-26 18:00 10 Hours
Continuous
50L (44s Bearspaw Plant - SS-21), 21.2TR (SS-21) HV SW Maintenance 21SW90. Spring Substation Washing. Reversing Switch Check - 21.2-TC  
ENMAX, ALTALINK 18-Apr-26 09:00 18-Apr-26 17:00 8 Hours
Continuous
50L (44s Bearspaw Plant - SS-21), 44s 50X (44s Bearspaw Plant) HV SW Maintenance 21SW90. Spring Substation Washing. ReversingSwitch Check - 21.2-TC  
ALTALINK, EPCOR 18-Apr-26 09:30 20-Apr-26 17:00 2.31 Days
Continuous
1056L (89s Ellerslie - 629s Argyll Transfer Station) 1056L: Aerial Washing Program  
ALTALINK, EPCOR 18-Apr-26 09:30 20-Apr-26 17:00 2.31 Days
Continuous
1056L (89s Ellerslie - 629s Argyll Transfer Station) 1056L: Aerial Washing Program
 
BCH 20-Apr-26 09:00 08-May-26 17:00 18.33 Days
Continuous
5L98 (BCH Nicola - BCH Vaseux Lake) replace spacer damper and insulator AB-BC
BCH 20-Apr-26 09:00 08-May-26 17:00 18.33 Days
Continuous
5L98 (BCH Nicola - BCH Vaseux Lake) replace spacer damper and insulator AB-BC
ATCO, CNRL 20-Apr-26 10:00 24-Apr-26 16:00 4.25 Days
Continuous
838s RTU/SCADA (838s Horizon Mining), 842s RTU/SCADA (842s Horizon Upgrading) Brief SCADA Outages(15-30min) while RTU updates are completed.  
ENMAX, ALTALINK 20-Apr-26 12:00 20-Apr-26 18:00 6 Hours
Continuous
28.80L (42s Sarcee - SS-28), 28.2TR (SS-28) Spring Substation Washing  
ATCO 20-Apr-26 12:00 24-Apr-26 17:00 4.21 Days
Continuous
813s SVC (813s Little Smoky) SVC MAINTENANCE  
ALTALINK, ENMAX 20-Apr-26 13:00 20-Apr-26 17:00 4 Hours
Continuous
42s 28 (42s Sarcee), 28.80L (42s Sarcee - SS-28) Spring Substation Washing  
ATCO 20-Apr-26 13:00 20-Apr-26 17:30 4.5 Hours
Continuous
755s 901 (755s Cordel) PRC-005 - TRIP & CLOSE COIL TESTING.  
ALTALINK 21-Apr-26 08:00 24-Apr-26 17:00 3.38 Days
Continuous
510s 2652 (510s Sunnybrook), 510s 2752 (510s Sunnybrook), AML 511s 4852 (AML 511s Crossings), AML 511s 4952 (AML 511s Crossings), 1325L (510s Sunnybrook - AML 511s Crossings) Repair of the base of DIW 1 drivetrain at Sunnybrook and Annual Valve cooling maintenance at Crossings  
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

 
ATCO 21-Apr-26 09:30 21-Apr-26 12:00 2.5 Hours
Continuous
755s 902 (755s Cordel) PRC-005 - TRIP & CLOSE COIL TESTING.  
ATCO 21-Apr-26 10:00 21-Apr-26 12:00 2 Hours
Continuous
789s 701 (789s Keg River), 7L64 (779s Chinchaga River - 789s Keg River) PRC Trip Coil Testing  
ATCO 21-Apr-26 12:01 21-Apr-26 14:00 119 Mins
Continuous
789s 702 (789s Keg River), 7L62 (789s Keg River - 797s Kemp River) PRC Trip Coil Testing  
ATCO 21-Apr-26 13:00 21-Apr-26 17:30 4.5 Hours
Continuous
755s 904 (755s Cordel) PRC-005 - TRIP & CLOSE COIL TESTING.  
ALTALINK, WPLP 22-Apr-26 08:30 22-Apr-26 16:30 8 Hours
Continuous
268s 503 (268s Whitecourt), 503L (268s Whitecourt - 323s Whitecourt Power) Customer outage for their work on 323s3.  
ATCO 22-Apr-26 09:30 24-Apr-26 17:30 2.33 Days
Continuous
755s 903 (755s Cordel) PRC-005 - TRIP & CLOSE COIL TESTING.  
ATCO 22-Apr-26 10:00 22-Apr-26 12:00 2 Hours
Continuous
789s 703 (789s Keg River), 7L59 (789s Keg River - 7L59 tap) PRC Trip Coil Testing  
ATCO 22-Apr-26 12:01 22-Apr-26 14:00 119 Mins
Continuous
789s 704 (789s Keg River), 7L58 (789s Keg River - 905s Meikle) PRC Trip Coil Testing  
ALTALINK 22-Apr-26 23:30 23-Apr-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenance  
ALTALINK 23-Apr-26 03:30 23-Apr-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
Syncrude 24-Apr-26 08:00 30-Apr-26 16:00 6.33 Days
Continuous
11A (Aurora), 11 (Aurora), 11B (Aurora), 21 (Aurora), 21A (Aurora), 21B (Aurora), 31 (Aurora), 31A (Aurora), 31B (Aurora), 89-210 (Aurora), 89-51 (Aurora), T1 (Aurora), 211A (Aurora), 212B (Aurora), 211 (Aurora), 222B (Aurora), 222 (Aurora), 222A (Aurora), 221B (Aurora), 221A (Aurora), 221 (Aurora), 89-224 (Aurora), G21 (Aurora), T4 (Aurora) SCL - G01 Zone 2 6yr PM  
ENMAX, ALTALINK 25-Apr-26 08:00 26-Apr-26 18:00 1.42 Days
Continuous
20.82L (SS-20 - SS-21), 21.80L (42s Sarcee - SS-21), 21.1TR (SS-21), 21.4TR (SS-21) HV SW Maintenance SW84, SW85, MD-21.4TR. Spring Substation Washing. 21.1TR west phase, corona on String bus insulator-on plate. Altalink required to remove AML VT4 60S100 fuses  
ALTALINK, ENMAX 25-Apr-26 09:00 26-Apr-26 17:00 1.33 Days
Continuous
42s 21 (42s Sarcee), 21.80L (42s Sarcee - SS-21) HV SW Maintenance SW84, SW85, MD-21.4TR. Spring Substation Washing. 21.1TR west phase, corona on String bus insulator-on plate. Altalink required to remove AML VT4 60S100 fuses  
BCH, BPA 26-Apr-26 09:00 30-Apr-26 17:00 4.33 Days
Continuous
5L52 (BPA Custer - BCH Ingledow) doble and inspection AB-BC
EPCOR 27-Apr-26 07:00 27-Apr-26 17:00 10 Hours
Continuous
RW2401 (EP Riverview) Riverview: RW2401 (SF6) Breaker Maintenance  
ALTALINK, EPCOR 27-Apr-26 07:00 30-Apr-26 17:00 3.42 Days
Continuous
1055L (629s Argyll Transfer Station - 816s Petrolia), 816s P2402 (816s Petrolia), 816s P2403 (816s Petrolia) 1055L/Petrolia: SA/CT/CVT Doble and PDS4/PDS5 Disconnect Maintenance and Aerial Washing Program  
ALTALINK 27-Apr-26 07:00 11-May-26 18:00 14.46 Days
Continuous
87s T2 (87s Gaetz), 87s 240kV East Bus (87s Gaetz), 87s 1552 (87s Gaetz), 87s 1652 (87s Gaetz), 87s 1952 (87s Gaetz), 87s 1252 (87s Gaetz) Closing Open points 'A' & 'C'  
ALTALINK, EPCOR 27-Apr-26 09:30 30-Apr-26 17:00 3.31 Days
Continuous
1057L (89s Ellerslie - 657s Summerside), 657s SU2401 (657s Summerside), 657s SU2402 (657s Summerside) 1057L/Summerside: CVT/Arrestor Doble, SUDS1/SUDS3/SUDS9 Disconnect Maintenance  
ALTALINK, EPCOR 27-Apr-26 09:30 30-Apr-26 17:00 3.31 Days
Continuous
89s 352 (89s Ellerslie), 89s 452 (89s Ellerslie), 1057L (89s Ellerslie - 657s Summerside) 1057L/Summerside: CVT/Arrestor Doble, SUDS1/SUDS3/SUDS9 Disconnect Maintenance  
ATCO 27-Apr-26 09:30 01-May-26 17:30 4.33 Days
Continuous
755s 905 (755s Cordel), 755s 906 (755s Cordel), 9L953 (574s Nilrem - 755s Cordel) PRC-005 - TRIP COIL TESTING - BREAKER 905 @ 755S
PRC-005 - TRIP & CLOSE COIL TESTING - BREAKER 906 @ 755S
Adjust 905B Switch at 755s Cordel
Adjust 906A Switch at 755s Cordel
Repair 9L953D1 at 755s Cordel
RTXP Test Switch Mitigation and Replacement
 
ATCO, ALTALINK 27-Apr-26 09:30 01-May-26 17:30 4.33 Days
Continuous
953L (574s Nilrem - 755s Cordel) Switch and breaker maintenance  
ATCO 27-Apr-26 12:00 04-May-26 12:00 7 Days
Continuous
730s STATCOM (730s Rycroft) SVC ANNUAL INSPECTION @ RYCROFT 730S
SVC FIRE SYSTEM INSPECTION @ RYCROFT 730S
 
ATCO 28-Apr-26 09:00 01-May-26 12:00 3.13 Days
Continuous
930s SVC (930s Arcenciel) SVC AIR COOLED MAINTENANCE @ ARCENCIEL 930S  
ALTALINK 29-Apr-26 07:30 07-May-26 12:00 8.19 Days
Continuous
275s T1 (275s Jenner) Relace switch 275s37 and 275s39. Replace 25kV post insulators  
ALTALINK 29-Apr-26 08:00 07-May-26 16:00 8.33 Days
Continuous
275s T1 (275s Jenner) 275sT1 Oil Reclaim, Maintenance, Plugged Radiator  
ENMAX 02-May-26 08:00 02-May-26 18:00 10 Hours
Continuous
162.1TR (SS-162), 240kV North Bus (SS-162), 138kV North Bus (SS-162) Summer Substation Washing  
ENMAX 03-May-26 08:00 03-May-26 18:00 10 Hours
Continuous
162.2TR (SS-162), 138kV South Bus (SS-162), 240kV South Bus (SS-162) Summer Substation Washing  
EPCOR 04-May-26 07:00 08-May-26 17:00 4.42 Days
Continuous
805s T4 (805s Jasper), EP 805s J2406 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: TX4 Relay Maintenance  
EPCOR 04-May-26 07:00 10-May-26 17:00 6.42 Days
Continuous
BR721 (Rossdale), 814s T1 (814s Bellamy), 814s B2401 (814s Bellamy), 814s B2407 (814s Bellamy) Bellamy: TX1 Zone Doble and BR721 Breaker Maintenance/Doble, and BDS15 Disconnect Maintenance  
EPCOR 04-May-26 07:00 10-May-26 17:00 6.42 Days
Continuous
557s T2 (557s Castle Downs), 557s CD2403 (557s Castle Downs), 557s CD2404 (557s Castle Downs) Castledowns: TX2 Doble, Tap Changer Maintenance, and CDAB2CDDS6/CDDS7 Disconnect Maintenance  
BCH, BPA 04-May-26 08:00 15-May-26 17:00 11.38 Days
Continuous
2L112 (BPA Boundary - BCH Nelway) emergency replacement of a boundary PCB AB-BC
ATCO 04-May-26 09:00 18-May-26 17:30 14.35 Days
Continuous
13L50 (2029s Heathfield - 2075s Newell) Kinbrook Addition to 2075s  
ATCO 04-May-26 09:00 18-May-26 17:30 14.35 Days
Continuous
2029s T11 (2029s Heathfield) Kinbrook Addition to 2075s Newell.  
ATCO 04-May-26 09:00 18-May-26 17:30 14.35 Days
Continuous
2075s T11 (2075s Newell) Kinbrook Addition to 2075s Newell.  
ALTALINK, GREENGATEP 04-May-26 18:00 06-Jun-26 17:00 32.96 Days
Continuous
962L (972s Tinchebray - 87s Gaetz) Switch needs to remain open until ATCO is ready @ 972s for energization  
ALTALINK, GREENGATEP 04-May-26 18:00 06-Jun-26 17:00 32.96 Days
Continuous
986L (972s Tinchebray - 87s Gaetz) Switch needs to remain open until ATCO is ready @ 972s for energization  
BCH 05-May-26 09:00 06-May-26 17:00 1.33 Days
Continuous
5L98 (BCH Nicola - BCH Vaseux Lake) NIC 5CB51 rebuild AB-BC
ATCO 05-May-26 09:00 07-May-26 17:00 2.33 Days
Continuous
9L59 (801s Anderson - 9LA59 tap), 9L59 (972s Tinchebray - 9LA59 tap) Connect new 907B to 900BS1
 
ALTALINK 06-May-26 08:00 07-May-26 17:00 1.38 Days
Continuous
132s 37 (132s Ware Junction), 132s 40 (132s Ware Junction), 275s 1852 (275s Jenner), 275s 1752 (275s Jenner), 951L (132s Ware Junction - 275s Jenner) Center phase socket clevis that holds yolk plate has a keeper key backed out.  
ATCO 07-May-26 09:00 19-May-26 17:00 12.33 Days
Continuous
9L16 (755s Cordel - 972s Tinchebray) GOI is required on 907B to isolate 908/909 bay and new 9L16.  
ATCO 08-May-26 09:00 09-May-26 17:00 1.33 Days
Continuous
972s 240kV Bus 900BS2 (972s Tinchebray) Connect new 909A to 900BS2  
ENMAX 09-May-26 07:00 09-May-26 12:00 5 Hours
Continuous
771L (SS-47 - SS-162), 162B138-RB82 (SS-162), 47.1TR (SS-47), 47B138-771/1 (SS-47), 47B138-771 (SS-47), 47.2TR (SS-47), 162B138-RB81 (SS-162) Summer Substation Washing  
ENMAX, ALTALINK 09-May-26 12:00 09-May-26 18:00 6 Hours
Continuous
162B138-RB80 (SS-162), 162B138-RB81 (SS-162), 162.81L (391s Balzac - SS-162) Summer Substation Washing  
ENMAX, ALTALINK 10-May-26 08:00 10-May-26 12:00 4 Hours
Continuous
162B240-RB133 (SS-162), 918L (281s Johnson - SS-162), 162B240-RB132 (SS-162) Summer Substation Washing  
ALTALINK 10-May-26 08:00 10-May-26 17:00 9 Hours
Continuous
268s 199N (268s Whitecourt), 199L (268s Whitecourt - 199AL tap) Replace keeper keys at structure 375  
ALTALINK 10-May-26 08:00 12-May-26 17:00 2.38 Days
Continuous
336s 612 (336s Fincastle), 368s 612 (368s Burdett), 612L (336s Fincastle - 368s Burdett) Replacing cross arms and insulators on structures 174, 196, 197, 198, 203, 205, 206, 207, 208, 209, 210, 211, and 212  
ENMAX, ALTALINK 10-May-26 12:00 10-May-26 18:00 6 Hours
Continuous
932L (74s Janet - SS-162), 162B240-RB136 (SS-162), 162B240-RB135 (SS-162) Summer Substation Washing  
EPCOR 11-May-26 07:00 13-May-26 17:00 2.42 Days
Continuous
557s T1 (557s Castle Downs) Castledowns: TX1 Tap Changer Maintenance and Conservator Pipe Leak Repair  
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  
EPCOR 11-May-26 07:00 17-May-26 17:00 6.42 Days
Continuous
814s T2 (814s Bellamy), BR722 (Rossdale), 814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy) Bellamy: TX2 Zone Doble and BR722 Breaker Maintenance/Doble, and BDS17 Disconnect Maintenance  
EPCOR 11-May-26 07:00 22-May-26 17:00 11.42 Days
Continuous
52s T1 (52s East Industrial) East Industrial: TX1 DGA Monitor Replacement  
ALTALINK, ATCO 11-May-26 08:00 14-May-26 16:00 3.33 Days
Continuous
72s 1052 (72s Leismer), 7L114 (72s Leismer - 7LA114 tap) Customer maintenance  
ALTALINK 11-May-26 08:00 14-May-26 17:00 3.38 Days
Continuous
72s T2 (72s Leismer), 72s 1052 (72s Leismer) Transformer maintenance, doble, install Coresense & Qualitrol  
ATCO 11-May-26 13:00 14-May-26 13:00 3 Days
Continuous
827s SVC (827s Cranberry Lake) SVC AIR COOLED MAINTENANCE
SVC AUX TRIP RELAY TESTING
SVC MICROPROCESSOR RELAY TESTING
SPR TESTING - TRANSFORMER 703T
TRIP COIL TESTING 401, 703
 
ATCO, ALTALINK, ENBRIDGE 11-May-26 13:00 14-May-26 13:00 3 Days
Continuous
7L114 (72s Leismer - 7LA114 tap), 7LA114 (658s Chard - 7L114 tap), 7L114 (907s Waddell - 7LA114 tap) Planned inspection on 7L114/7LA114 to take place during the AltaLink outage to their T2 transformer at 72S  
ALTALINK, ICPCL 12-May-26 08:00 13-May-26 17:00 1.38 Days
Continuous
225s 225E (225s Magrath), 67s 225 (67s Stirling), 225AL (313s Raymond Reservoir - 225L tap), 225L (225s Magrath - 225AL tap), 225L (67s Stirling - 225AL tap) 93, 149 replace arms and insulators  
ATCO, ALBIAN, CNRL 14-May-26 08:00 29-May-26 16:00 15.33 Days
Continuous
919s 908 (919s Hartley), 847s 902T (847s Muskeg River) CNRL Request
COG to open 908 breaker and 902TD in the Hartley 919S substation at CNRL Albian Sands.
 
SUNCOR 18-May-26 08:00 24-May-26 20:00 6.5 Days
Continuous
29PL9-12 (29EDD-34 - 29EDD-65) 29EDD34;29PL9-12 SYSTEM;PM 5y,10y
 
EPCOR 19-May-26 07:00 01-Jun-26 07:00 13 Days
Continuous
T1 (Rossdale), R721 (Rossdale), RR723 (Rossdale), BR722 (Rossdale), 814s T2 (814s Bellamy) Rossdale: TX1 LCR Demo  
EPCOR 19-May-26 07:00 10-Jul-26 17:00 52.42 Days
Continuous
805s T4 (805s Jasper), EP 805s J2405 (EP 805s Jasper), EP 805s J2406 (EP 805s Jasper) Jasper: J2406/JDS10 Replacement LCR  
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.
 
ALTALINK 19-May-26 23:00 21-May-26 07:00 1.33 Days
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 20-May-26 07:00 21-May-26 07:00 24 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ALTALINK 20-May-26 07:30 28-May-26 12:00 8.19 Days
Continuous
275s T2 (275s Jenner) Replace switch 275s45, 275s49, 275s47. Replace 25kV Post Insulators  
ATCO 20-May-26 08:00 21-May-26 13:00 29 Hours
Continuous
9L84 (934s Blackfly - 977s Salt Creek) Outage on 9L84 to replace 3 damaged insulator strings on structure 47
 
ALTALINK 20-May-26 09:00 28-May-26 17:00 8.33 Days
Continuous
275s T2 (275s Jenner) 275sT2 Oil Reclaim and Maint.  
ALTALINK, Lethbridge 22-May-26 08:00 22-May-26 17:00 9 Hours
Continuous
207L (111s Coalbanks - 370s North Lethbridge) 207L Hardware tightening on structure 8  
ENMAX, ALTALINK 23-May-26 08:00 23-May-26 11:00 3 Hours
Continuous
5s T1 (5s East Calgary) Summer Substation Washing  
ENMAX, ALTALINK 23-May-26 11:00 23-May-26 13:00 2 Hours
Continuous
5s T2 (5s East Calgary) Summer Substation Washing  
EPCOR 25-May-26 07:00 27-May-26 17:00 2.42 Days
Continuous
816s P2401 (816s Petrolia) Petrolia: P2401 CT Doble  
EPCOR 25-May-26 07:00 05-Jun-26 17:00 11.42 Days
Continuous
987s T4 (987s Clover Bar), 987s C2408 (987s Clover Bar) Cloverbar: TX4 DGA Monitor Replacement and Relay Maintenance  
ATCO 25-May-26 09:00 27-May-26 17:30 2.35 Days
Continuous
2075s 911 (2075s Newell) BREAKER SF6 3AP4FI MAINTENANCE  
ATCO 25-May-26 10:00 26-May-26 16:00 30 Hours
Continuous
715s 701 (715s Leming Lake), 7L583 (715s Leming Lake - 970s Bourque) PRC-005 Trip Coil Testing, 701CT Inspection/ Testing  
ALTALINK 25-May-26 14:00 01-Jun-26 13:30 6.98 Days
Continuous
63s 352 (63s Red Deer) 63s352 Breaker Replacement.

Outage to be expanded to include line to eliminate LOA hazard with overhead line while lifting breaker onto structure. Grounds will remain installed during transfer of GOI to include the overhead line.

Associated request for the expanded outage #26-10204
 
ATCO 26-May-26 08:00 26-May-26 09:59 119 Mins
Continuous
898s 901 (898s Heart Lake) PRC-005 TRIP COIL TESTING

 
ATCO 26-May-26 10:00 26-May-26 11:59 119 Mins
Continuous
898s 902 (898s Heart Lake) PRC-005 TRIP COIL TESTING

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

 
ATCO 26-May-26 14:00 26-May-26 15:59 119 Mins
Continuous
898s 905 (898s Heart Lake) PRC-005 TRIP COIL TESTING

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

 
ALTALINK 27-May-26 09:00 27-May-26 17:00 8 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)  
ATCO 27-May-26 10:00 27-May-26 11:59 119 Mins
Continuous
898s 908 (898s Heart Lake) PRC-005 TRIP COIL TESTING

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

 
ATCO 27-May-26 14:00 28-May-26 12:59 22.98 Hours
Continuous
898s 904 (898s Heart Lake) PRC-005 TRIP COIL TESTING, B PHASE MOTOR CCT DC FAIL TROUBLESHOOTING/ REPAIR

 
EPCOR 28-May-26 07:00 30-May-26 17:00 2.42 Days
Continuous
816s P2405 (816s Petrolia) Petrolia: P2405 CT Doble  
EPCOR 01-Jun-26 07:00 03-Jun-26 17:00 2.42 Days
Continuous
816s P2406 (816s Petrolia) Petrolia: P2406 CT Doble  
EPCOR 01-Jun-26 07:00 07-Jun-26 17:00 6.42 Days
Continuous
T4 (Poundmaker), PM721 (Poundmaker), PM2402 (Poundmaker), PM2403 (Poundmaker) Poundmaker: TX4 Doble and PMAB4/PMDS4/PMDS5 Disconnect Maintenance  
ALTALINK 01-Jun-26 08:00 11-Jun-26 15:00 10.29 Days
Continuous
19s 905 (19s Wabamun), 37s Protection & Control (37s North Calder), 37s 82 (37s North Calder), 37s 76 (37s North Calder), 905L (19s Wabamun - 37s North Calder) Protection upgrade  
ATCO 01-Jun-26 10:00 02-Jun-26 16:00 30 Hours
Continuous
715s 703 (715s Leming Lake), 7L66 (715s Leming Lake - 717s Ethel Lake) PRC-005 Trip Coil Testing, 703CT Inspection/ Testing  
ALTALINK 01-Jun-26 14:00 04-Jun-26 16:00 3.08 Days
Continuous
63s 352 (63s Red Deer), 925L (63s Red Deer - 74s Janet) 63s352 Breaker Replacement.

Expanding outage to include line to eliminate LOA hazard with overhead line while lifting breaker onto structure. Grounds will remain installed during transfer of GOI to include the overhead line.

Associated request for previous outage #26-10158
 
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
 
SUNCOR 06-Jun-26 08:00 09-Jun-26 20:00 3.5 Days
Continuous
29EDD-1 29EDD1s952 (29EDD-1 Millennium) 29EDD1s952 - Faulty SF6 Sensors - 300677553  
ALTALINK, BCH 07-Jun-26 08:00 07-Jun-26 17:00 9 Hours
Continuous
786L (799s Coleman - BCH Natal) Repairing woodpecker damage on structures 94, 112 and 118
Replacing damaged insulator on structure 121
 
EPCOR, ALTALINK 08-Jun-26 07:00 14-Jun-26 17:00 6.42 Days
Continuous
657s T3 (657s Summerside), 657s SU2405 (657s Summerside), 657s SU2401 (657s Summerside) Summerside: TX3 Doble and SUAB3/SUDS2/SUDS12 Disconnect Maintenance  
SUNCOR 10-Jun-26 08:00 13-Jun-26 20:00 3.5 Days
Continuous
29EDD-1 29EDD1s852 (29EDD-1 Millennium) 29EDD1S852 Replace Densimeter  
ALTALINK 10-Jun-26 23:30 11-Jun-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 11-Jun-26 03:30 11-Jun-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ALTALINK 11-Jun-26 10:00 11-Jun-26 12:00 2 Hours
Continuous
37s 88 (37s North Calder) Breaker fail trip testing  
ALTALINK 11-Jun-26 13:00 11-Jun-26 15:00 2 Hours
Continuous
37s 81 (37s North Calder) Breaker fail trip testing  
SUNCOR 14-Jun-26 08:00 17-Jun-26 20:00 3.5 Days
Continuous
29EDD-1 29EDD1s1052 (29EDD-1 Millennium) 29EDD1S1052 Densimeter Replacement - 300347749  
ATCO 14-Jun-26 09:00 25-Jun-26 17:00 11.33 Days
Continuous
9L62 (972s Tinchebray - 87s Gaetz) Work on parallel line 9L86  
ATCO, CNRL 15-Jun-26 05:00 29-Jun-26 10:00 14.21 Days
Continuous
859s 701TD (859s Primrose), 859s 701 (859s Primrose), 859s 704 (859s Primrose), 859s Protection & Control (859s Primrose), 859s RTU/SCADA (859s Primrose), 859s 52G (859s Primrose), 859s 701T (859s Primrose) maintenance  
EPCOR 15-Jun-26 07:00 19-Jun-26 17:00 4.42 Days
Continuous
987s GT2 (987s Clover Bar) Cloverbar:  
ALTALINK 15-Jun-26 09:00 15-Jun-26 16:00 7 Hours
Continuous
37s Protection & Control (37s North Calder) 930L MOD (37s72) supervisory cutovers and function testing  
ATCO 15-Jun-26 09:30 17-Jun-26 17:30 2.33 Days
Continuous
801s 909 (801s Anderson) BREAKER MIN OIL HLR COMPLETE TESTING  
ALTALINK, EPCOR 15-Jun-26 09:30 19-Jun-26 17:00 4.31 Days
Continuous
915L (38s East Edmonton - 987s Clover Bar), 987s C2403 (987s Clover Bar), 987s C2405 (987s Clover Bar) 915L/Cloverbar: CT/CVT/SA Doble and CDS35/CDS36/CDS7 Disconnect Maintenance and Relay Maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 19-Jun-26 17:00 4.31 Days
Continuous
915L (38s East Edmonton - 987s Clover Bar) 915L/Cloverbar: CT/CVT/SA Doble and CDS35/CDS36/CDS7 Disconnect Maintenance and Relay Maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 20-Jun-26 17:00 5.31 Days
Continuous
1139L (367s Harry Smith - EP Riverview), RW2405 (EP Riverview), RW2403 (EP Riverview) Riverview: 1139L Zone Doble and RWDS6/RWDS9/RWSA12 Disconnect Maintenance and RW2403/RW2405 (SF6) Breaker Maintenance  
ALTALINK, EPCOR 15-Jun-26 09:30 20-Jun-26 17:00 5.31 Days
Continuous
1139L (367s Harry Smith - EP Riverview) Riverview: 1139L Zone Doble and RWDS6/RWDS9/RWSA12 Disconnect Maintenance and RW2403/RW2405 (SF6) Breaker Maintenance  
ATCO 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
 
EPCOR 17-Jun-26 07:00 24-Jun-26 17:00 7.42 Days
Continuous
987s GT3 (987s Clover Bar) maintenance  
ATCO 18-Jun-26 09:30 19-Jun-26 17:30 1.33 Days
Continuous
801s 902 (801s Anderson) BREAKER MIN OIL HLR COMPLETE TESTING  
EPCOR 22-Jun-26 07:00 25-Jun-26 17:00 3.42 Days
Continuous
987s GT1 (987s Clover Bar) maintenance  
EPCOR 22-Jun-26 07:00 28-Jun-26 17:00 6.42 Days
Continuous
52s T1 (52s East Industrial) East Industrial: TX1 Doble  
SUNCOR 22-Jun-26 08:00 28-Jun-26 20:00 6.5 Days
Continuous
29PL9-17 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT419 / 29PL9-17 SYSTEM;PM 5y,10y; 29PL9-17 Powerline & OHSW repairs
 
ATCO 22-Jun-26 09:00 26-Jun-26 16:00 4.29 Days
Continuous
969s 701T (969s Lindbergh) total station outage to replace failing HO/XO bushings on transformer, updates to anti-islanding RAS logic and alarming, replace NGR resistor and relay
 
ALTALINK, EPCOR 22-Jun-26 09:30 27-Jun-26 17:00 5.31 Days
Continuous
921L (71s Lamoureux - 987s Clover Bar), 987s C2404 (987s Clover Bar), 987s C2406 (987s Clover Bar) 921L/Cloverbar: CT/CVT/SA Doble and CDS9/CDS14/CDS17 Disconnect Maintenance and C2404 (Min Oil) Breaker Maintenance and C2401 Relay Maintenance  
ALTALINK, EPCOR 22-Jun-26 09:30 27-Jun-26 17:00 5.31 Days
Continuous
921L (71s Lamoureux - 987s Clover Bar) 921L/Cloverbar: CT/CVT/SA Doble and CDS9/CDS14/CDS17 Disconnect Maintenance and C2404 (Min Oil) Breaker Maintenance and C2401 Relay Maintenance  
SUNCOR 29-Jun-26 08:00 02-Jul-26 19:00 3.46 Days
Continuous
29PL9-16 (29EDD-1 Millennium - 29EDD-94 Voyageur) 29EDD1;29PT418/29PL9-16 SYSTEM;PM 5y,10y
 
ATCO 29-Jun-26 13:00 30-Jun-26 17:00 28 Hours
Continuous
9LA93 (973s Lanes Lake - 9L93 tap) Line to Ground Clearance Mitigation, Span 50-51. Repair deficiency on structure 57  
ATCO, SUNCOR 03-Jul-26 08:00 09-Jul-26 20:00 6.5 Days
Continuous
29PL9-1 (29EDD-1 Millennium - 848s Ruth Lake), 29EDD-1 29EDD1s452 (29EDD-1 Millennium) 29EDD1;29CVT-3 SYSTEM;PM 5y,10y; 29EDD1;29EDD1S452 MAINT&TEST;PM 10y; 29EDD1;29CVT-3 SYSTEM;PM 5y,10y; 29PL9-1 Str#5 vibration damper
 
EPCOR 06-Jul-26 07:00 12-Jul-26 17:00 6.42 Days
Continuous
987s T2 (987s Clover Bar), 987s CC721 (987s Clover Bar), 987s C2406 (987s Clover Bar), 987s C2410 (987s Clover Bar) Cloverbar: TX2 Doble and CDS1/CDS31/CDS33/CDS43 Disconnect Maintenance and Measurements w/Engineering  
ATCO 06-Jul-26 10:00 07-Jul-26 16:00 30 Hours
Continuous
825s 901 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 08-Jul-26 10:00 09-Jul-26 16:00 30 Hours
Continuous
825s 902 (825s Whitefish Lake) BREAKER MAINTENANCE  
ENMAX, ALTALINK 10-Jul-26 08:00 10-Jul-26 16:00 8 Hours
Continuous
37.82L (74s Janet - SS-37) Shield Wire Replacement.  
ATCO, SUNCOR 10-Jul-26 08:00 16-Jul-26 20:00 6.5 Days
Continuous
29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake), 29EDD-1 29EDD1s152 (29EDD-1 Millennium) 29EDD1;29CVT-1 SYSTEM;PM 5y,10y  
EPCOR 13-Jul-26 07:00 19-Jul-26 17:00 6.42 Days
Continuous
EP 803s L2401 (EP 803s Lambton) Lambton: L2401 (Min Oil) Breaker Maintenance and CT Doble  
EPCOR 13-Jul-26 07:00 18-Sep-26 17:00 67.42 Days
Continuous
805s T3 (805s Jasper), EP 805s J2404 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper) Jasper: J2402/JAB3/JDS9 Replacement LCR  
ATCO 13-Jul-26 10:00 14-Jul-26 16:00 30 Hours
Continuous
825s 903 (825s Whitefish Lake) BREAKER 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 25-Jul-26 20:00 10.5 Days
Continuous
29EDD-2 29PT-3 (29EDD-2 Tar Island), 29PL6-22 (29EDD-1 Millennium - 29EDD-2 Tar Island) 29EDD2;29PT-3, 29PL6-22 SYSTEM;PM 5y,10y
 
ALTALINK 15-Jul-26 10:00 15-Jul-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ATCO 15-Jul-26 10:00 16-Jul-26 16:00 30 Hours
Continuous
825s 904 (825s Whitefish Lake) BREAKER MAINTENANCE  
ALTALINK 16-Jul-26 10:00 16-Jul-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ATCO, SUNCOR 17-Jul-26 08:00 23-Jul-26 20:00 6.5 Days
Continuous
6L32 (29EDD-1 Millennium - 737s ATC Horseshoe), 29EDD-1 29EDD1S28 (29EDD-1 Millennium), 29EDD-1 29PS-197 (29EDD-1 Millennium) 29EDD1;29CVT-6 SYSTEM;5y,10y; 29EDD1s28 Alignment Issues; 29PS-197 Paddle Rotation
 
EPCOR 20-Jul-26 07:00 26-Jul-26 17:00 6.42 Days
Continuous
EP 803s L2402 (EP 803s Lambton) Lambton: L2402 (Min Oil) Breaker Maintenance and CT Doble  
ALTALINK, TRANSALTA 20-Jul-26 08:00 23-Jul-26 17:00 3.38 Days
Continuous
179s 733 (179s Gleichen), 428s 733X (428s Namaka), 733L (179s Gleichen - 428s Namaka) Interphase spacers str: 181, 193, 195, 196
Repair conductor with sleeve or preform splice: 181,193, 195, 196
Str change: 211 (foundation in concrete)
arm/insulator change str: 161, 163, 165
"
 
ALTALINK 20-Jul-26 09:30 20-Jul-26 15:00 5.5 Hours
Continuous
138s 2552 (138s Windy Flats), 603L (138s Windy Flats - 243s Soderglen) Job Scope: We need to complete maintenance on 243s138DS1  
ATCO 20-Jul-26 10:00 21-Jul-26 16:00 30 Hours
Continuous
825s 905 (825s Whitefish Lake) BREAKER MAINTENANCE  
ATCO 20-Jul-26 10:00 22-Jul-26 12:00 2.08 Days
Continuous
804s 702 (804s Wintering Hills), 7L85 (804s Wintering Hills - 7LA85 tap) BREAKER SF6 GL312 TESTING - 702 @ 804S  
ALTALINK 20-Jul-26 13:30 23-Jul-26 17:30 3.17 Days
Continuous
245s 777X (245s Seebe), 777L (48s Pocaterra - 245s Seebe) 245s777X 138kV CT replacement  
ALTALINK 20-Jul-26 14:00 27-Jul-26 13:30 6.98 Days
Continuous
63s 452 (63s Red Deer) 63s452 Breaker Replacement.

Outage to be expanded to include line to eliminate LOA hazard with overhead line while lifting breaker onto structure. Grounds will remain installed during transfer of GOI to include the overhead line.

Associated request for the expanded outage #26-10198
 
ATCO 21-Jul-26 08:00 22-Jul-26 17:00 1.38 Days
Continuous
7L65 (709s Vegreville - 7LA65 tap), 7L65 (710s Vermilion - 7LA65 tap), 7LA65 (708s Grizzly Bear - 7L65 tap) Switch Repairs, 7LA65D1  
ATCO, OWF2 22-Jul-26 12:00 24-Jul-26 17:30 2.23 Days
Continuous
804s 703 (804s Wintering Hills), 7L153 (609s Wheatland - 804s Wintering Hills) BREAKER SF6 GL312 TESTING - 703 @ 804S  
SUNCOR 24-Jul-26 08:00 06-Aug-26 20:00 13.5 Days
Continuous
29EDD-34 29PT-341 (29EDD-34), 29EDD-34 29-952-142 (29EDD-34), 29EDD-34 29-952-143 (29EDD-34), 29EDD-34 29-652-10200T (29EDD-34), 29EDD-34 29-652-10301 (29EDD-34), 29EDD-34 29-652-10302 (29EDD-34), 29EDD-34 29-652-10303 (29EDD-34), 29EDD-34 29PS-0375 (29EDD-34), 29EDD-34 29PS-0380 (29EDD-34), 29EDD-34 29PS-0381 (29EDD-34), 29EDD-34 29PS-0383 (29EDD-34), 29EDD-34 29PS-609 (29EDD-34) 10 year PM on 29EDD34;29PT-341 system and 5 year, 10 year PM on 29EDD34;29PP-103 system
 
SUNCOR 25-Jul-26 08:00 31-Jul-26 20:00 6.5 Days
Continuous
29PL9-3 (29EDD-1 Millennium - 29EDD-3), 29EDD-3 29PT-6 (29EDD-3) 29EDD1;29CVT-4 SYSTEM;PM 5y,10y;
 
ALTALINK, TRANSALTA 27-Jul-26 08:00 30-Jul-26 17:00 3.38 Days
Continuous
179s 733 (179s Gleichen), 428s 733X (428s Namaka), 733L (179s Gleichen - 428s Namaka) Interphase spacers str: 181, 193, 195, 196
Repair conductor with sleeve or preform splice: 181,193, 195, 196
Str change: 211 (foundation in concrete)
arm/insulator change str: 161, 163, 165
"
 
ALTALINK, EPCOR 27-Jul-26 09:30 31-Jul-26 17:00 4.31 Days
Continuous
909L (310p Sundance - 665s Dome), 665s D2403 (665s Dome) 909LW/Dome: CVT/SA Doble and DDS6/DDS7/DDS14 Disconnect Maintenance and 909LW Relay Maintenance  
ALTALINK, EPCOR 27-Jul-26 09:30 31-Jul-26 17:00 4.31 Days
Continuous
310p 1352 (310p Sundance), 310p 1452 (310p Sundance), 909L (310p Sundance - 665s Dome) 909LW/Dome: CVT/SA Doble and DDS6/DDS7/DDS14 Disconnect Maintenance and 909LW Relay Maintenance  
ATCO 27-Jul-26 10:00 31-Jul-26 17:30 4.31 Days
Continuous
801s 901T (801s Anderson), 801s 704 (801s Anderson), 7L85 (801s Anderson - ATC 803s Bullpound) PRC-005 - SPR TESTING - TRANSFORMER 901T @ 801S
Replace X3 Bushing on 901T at 801s Anderson
TRANSFORMER CLASS1 MAJOR TESTING - 901T @ 801S
TRANSFORMER CLASS1 TAP CHANGER - 901T @ 801S
BREAKER MIN OIL HLR PARTIAL TESTING - 704 @ 801S
 
ALTALINK 27-Jul-26 14:00 30-Jul-26 16:00 3.08 Days
Continuous
63s 452 (63s Red Deer), 1083L (63s Red Deer - 288s Wolf Creek) 63s452 Breaker Replacement.

Expanding outage to include line to eliminate LOA hazard with overhead line while lifting breaker onto structure. Grounds will remain installed during transfer of GOI to include the overhead line.

Associated request for previous outage #26-101157
 
ALTALINK 29-Jul-26 23:30 30-Jul-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 30-Jul-26 03:30 30-Jul-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ALTALINK 06-Aug-26 07:00 06-Aug-26 18:00 11 Hours
Daily
237s 2352 (237s Foothills), 237s 2652 (237s Foothills), 237s T2 (237s Foothills), 237s 240kV Bus 2 (237s Foothills) Install bus support piles for new 240kV Bay.  
ALTALINK 07-Aug-26 07:00 07-Aug-26 18:00 11 Hours
Daily
237s 2152 (237s Foothills), 237s 2452 (237s Foothills), 237s T1 (237s Foothills), 237s 240kV Bus 1 (237s Foothills) Install bus support piles for new 240kV Bay.  
SUNCOR 07-Aug-26 08:00 20-Aug-26 20:00 13.5 Days
Continuous
29EDD-34 29PT-340 (29EDD-34) 29EDD34;29PT-340 SYSTEM;PM 5y,10y; 29EDD34;29PP-102 SYSTEM;PM 5y,10y
 
EPCOR 10-Aug-26 07:00 16-Aug-26 17:00 6.42 Days
Continuous
665s T3 (665s Dome), 665s D721 (665s Dome), 665s D2404 (665s Dome), S721 (Strathcona) DS26/Dome/Strathcona: Dome TX3 Doble and DAB3/DDS15/DDS16 Disconnect Maintenance and Strathcona DS26/CVT Doble and SDS3 Disconnect Maintenance  
ALTALINK 10-Aug-26 09:30 13-Aug-26 17:00 3.31 Days
Continuous
702L (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 10-Aug-26 10:00 13-Aug-26 16:30 3.27 Days
Continuous
7L702 (137s Sedgewick - 757s Battle River) Interphase spacers and pole replacements  
ATCO 10-Aug-26 10:00 14-Aug-26 17:30 4.31 Days
Continuous
959s SVC (959s Lanfine) DFR Upgrade / Replacement
SVC Transformer Maintenance
Fire system inspection
Install Blocking Switches
Mechanical Maintenance & Capital
BATTERY CHARGER COMPLETE TESTING @ LANFINE 959S SVC DC MOTOR
 
ALTALINK, EPCOR 17-Aug-26 09:30 22-Aug-26 17:00 5.31 Days
Continuous
920L (71s Lamoureux - 557s Castle Downs), 557s CD2405 (557s Castle Downs), 557s CD2404 (557s Castle Downs) 920LE/Castledowns: CT/CVT Doble and Surge Arrestor LCR  
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  
EPCOR, ALTALINK 31-Aug-26 07:00 13-Sep-26 17:00 13.42 Days
Continuous
EP 803s T3 (EP 803s Lambton), EP 803s L2403 (EP 803s Lambton), EP 803s L2405 (EP 803s Lambton), EP 803s L721 (EP 803s Lambton), 72LS24 (EP 803s Lambton - Strathcona), 72LH8 (EP 803s Lambton - EP Hardisty), H726 (EP Hardisty), S724 (Strathcona) Lambton: LDS14 LCR and L721 Breaker Maintenance (Min Oil) and TX3 Zone Doble and L2405 Breaker Maintenance (SF6) and LDS12 Drive Pipe Repair and TX3 Relay Maintenance  
EPCOR 07-Sep-26 07:00 11-Sep-26 17:00 4.42 Days
Continuous
987s GT2 (987s Clover Bar) Cloverbar:  
ATCO 08-Sep-26 10:00 10-Dec-26 16:00 93.29 Days
Continuous
2015s 902 (2015s Yeo) Remove circuit breaker for use at 2102S Armistead. New breaker to be installed at 2015S Yeo substation once received from manufacturer.  
ALTALINK 08-Sep-26 23:00 09-Sep-26 07:00 8 Hours
Continuous
250p 2 (250p Bighorn Plant) Fall Leakage Test  
ALTALINK 09-Sep-26 07:00 10-Sep-26 07:00 24 Hours
Continuous
250p 1 (250p Bighorn Plant) Fall Leakage Test  
EPCOR 14-Sep-26 07:00 21-Sep-26 17:00 7.42 Days
Continuous
987s GT3 (987s Clover Bar) Cloverbar:  
ALTALINK, EPCOR 14-Sep-26 09:30 17-Sep-26 17:00 3.31 Days
Continuous
920L (37s North Calder - 557s Castle Downs), 557s CD2401 (557s Castle Downs), 557s CD2403 (557s Castle Downs) 920LW/Castledowns: Surge Arrestor LCR  
ATCO, ALTALINK 14-Sep-26 10:00 28-Sep-26 17:30 14.31 Days
Continuous
840s 901T (840s McNeill Station), 830L (562s Cypress - 840s McNeill Station), 840s 701 (840s McNeill Station), 840s 901 (840s McNeill Station) Replace 901T bushings
901T Oil Leak Absorption Repairs At 840s McNeill
AB-SK
ALTALINK 15-Sep-26 09:30 24-Sep-26 17:00 9.31 Days
Continuous
618s 725 (618s Riverbend), 725AL (618s Riverbend - 725L tap), 725L (111s Coalbanks - 725AL tap), 725L (674s Bowron - 725AL tap) Outage required to replace 674s12-Disconnect Switch and 674sPT5-CVT  
ALTALINK 16-Sep-26 23:30 17-Sep-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 17-Sep-26 03:30 17-Sep-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
EPCOR 21-Sep-26 07:00 03-Oct-26 17:00 12.42 Days
Continuous
987s CCP7213 (987s Clover Bar), 987s CCP7214 (987s Clover Bar), 987s C2401 (987s Clover Bar), 987s C2403 (987s Clover Bar), 987s T1 (987s Clover Bar) Cloverbar: C2401/C2403 Breaker Maintenance and CT Doble and CDS19 LCR and C2401 Relay Maintenance  
EPCOR 21-Sep-26 07:00 30-Oct-26 17:00 39.42 Days
Continuous
EP 805s J2405 (EP 805s Jasper) Jasper: J2405 Replacement LCR  
ATCO 21-Sep-26 10:00 24-Sep-26 16:00 3.25 Days
Continuous
888s 906 (888s Dover) 21B/9L74 relay replacement. Cutover breaker and CT to new protection  
EPCOR 22-Sep-26 07:00 25-Sep-26 17:00 3.42 Days
Continuous
987s GT1 (987s Clover Bar), 987s SST2 (987s Clover Bar), 987s CS2 (987s Clover Bar), 987s CGB1 (987s Clover Bar), 987s CCP7214 (987s Clover Bar), 987s CC24 (987s Clover Bar), 987s CH724 (987s Clover Bar), 987s CK726 (987s Clover Bar), 987s 72kV Bus 4 (987s Clover Bar) Cloverbar: , SST2, BUS 4 Outage. CDS18 Disconnect Replacement  
ALTALINK 22-Sep-26 08:00 22-Sep-26 18:00 10 Hours
Continuous
608AL (528s Blue Trail Wind Farm - 608L tap) Removing D608BL conductors from existing str 608AL32 for salvage. Adding new 608AL32A.
 
ALTALINK 24-Sep-26 08:00 24-Sep-26 18:00 10 Hours
Continuous
138s 2552 (138s Windy Flats), 603L (138s Windy Flats - 243s Soderglen) Removing D603AL conductors from existing str 603L97 for salvage. Replacing 603L98.
 
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  
Lethbridge 28-Sep-26 09:00 15-Oct-26 17:00 17.33 Days
Continuous
674s 1 (674s Bowron), 725LW (674s Bowron - 725BL tap) Line outage required on 725LW at 674s to replace 674s1-Manual Airbreak Switch and replace 674s2 and 674s6 PT's  
ALTALINK, Lethbridge 28-Sep-26 10:00 15-Oct-26 17:00 17.29 Days
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 replace 674s1-Disconnect Switch, 674sPT4-CVT, 674sPTB2-3phase CVT's, new screw piles and structure for 674sPTB2-CVT's  
EPCOR 05-Oct-26 07:00 18-Oct-26 17:00 13.42 Days
Continuous
CV5 (EP 511s Victoria - 557s Castle Downs) CV5: Manhole Inspections and Maintenance  
ALTALINK 05-Oct-26 08:30 28-Nov-26 06:30 53.96 Days
Continuous
62s 2 (62s Brazeau Plant) maintenence  
ATCO 05-Oct-26 10:00 08-Oct-26 16:00 3.25 Days
Continuous
9L74 (888s Dover - 960s Birchwood Creek) 21B/9L74 relay three terminal line testing  
ATCO 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  
ALTALINK 19-Oct-26 07:00 20-Oct-26 18:00 1.46 Days
Continuous
237s 2352 (237s Foothills), 237s 2652 (237s Foothills), 237s T2 (237s Foothills), 237s 240kV Bus 2 (237s Foothills) Closing Open Point 'C'  
EPCOR 19-Oct-26 07:00 30-Oct-26 17:00 11.42 Days
Continuous
814s T1 (814s Bellamy), BR721 (Rossdale), 814s B2401 (814s Bellamy), 814s B2407 (814s Bellamy) Bellamy: TX1 LTC Monitor Install  
ALTALINK, EPCOR 19-Oct-26 09:30 25-Oct-26 17:00 6.31 Days
Continuous
908L (89s Ellerslie - 816s Petrolia), 816s P2401 (816s Petrolia), 816s P2406 (816s Petrolia) Petrolia: 908LE Surge Arrestor and CVT LCR  
ALTALINK 21-Oct-26 07:00 22-Oct-26 18:00 1.46 Days
Continuous
237s 2152 (237s Foothills), 237s 2452 (237s Foothills), 237s T1 (237s Foothills), 237s 240kV Bus 1 (237s Foothills), 1141L (1172s Laramide - 237s Foothills) Closing Open Points 'A' & 'B'  
ALTALINK, EPCOR 26-Oct-26 07:00 30-Oct-26 17:00 4.42 Days
Continuous
909L (89s Ellerslie - 665s Dome), 665s D2401 (665s Dome), 665s D2404 (665s Dome), 72DS26 (665s Dome - Strathcona) 909LE/Dome: Dome CVT LCR and 909LE Metering Upgrade  
ATCO 26-Oct-26 10:00 29-Oct-26 16:00 3.25 Days
Continuous
9L74 (888s Dover - 960s Birchwood Creek) 21B/9L74 relay three terminal line testing  
ATCO, ALTALINK 26-Oct-26 10:00 02-Nov-26 16:00 7.29 Days
Continuous
7L230 (69s North Barrhead - 888AL tap), 7L230 (743s Sarah Lake - 888AL tap) Replace 7L230D1 disconnect switch  
ALTALINK 28-Oct-26 10:00 28-Oct-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 29-Oct-26 10:00 29-Oct-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ATCO 30-Oct-26 10:00 02-Nov-26 17:00 3.33 Days
Continuous
7L238 (959s Lanfine - 601s Bufallo Bird), 959s 708 (959s Lanfine), 959s 707 (959s Lanfine) Cutover CT/PT ccts, Commission new RAS A-B/7L238, end-to-end testing with 601S Buffalo Bird  
EPCOR 02-Nov-26 07:00 06-Nov-26 17:00 4.42 Days
Continuous
EP 805s J2407 (EP 805s Jasper) Jasper: J2407 Replacement LCR  
EPCOR 02-Nov-26 07:00 13-Nov-26 17:00 11.42 Days
Continuous
814s T2 (814s Bellamy), BR722 (Rossdale), 814s B2402 (814s Bellamy), 814s B2406 (814s Bellamy) Bellamy: TX2 LTC Monitor Install  
ALTALINK 05-Nov-26 03:30 05-Nov-26 06:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK, EPCOR 06-Nov-26 07:00 27-Nov-26 17:00 21.42 Days
Continuous
1045L (EP 805s Jasper - 1045AL tap), EP 805s J2407 (EP 805s Jasper), EP 805s J2406 (EP 805s Jasper), EP 805s J2401 (EP 805s Jasper), 1098L (EP 805s Jasper - Poundmaker) 1045L/1098L/Jasper: J2407 Replacement LCR and Line Drop Repair (Aerial)  
EPCOR 09-Nov-26 07:00 11-Dec-26 17:00 32.42 Days
Continuous
52s T2 (52s East Industrial), 52s E2402 (52s East Industrial) East Industrial: TX2 Bushing Replacement  
EPCOR 09-Nov-26 07:00 11-Dec-26 17:00 32.42 Days
Continuous
PM2405 (Poundmaker) Poundmaker: P2405 Breaker Replacement  
ATCO 09-Nov-26 10:00 12-Nov-26 17:00 3.29 Days
Continuous
9L24 (946s Oakland - 959s Lanfine), 959s 906 (959s Lanfine), 959s 905 (959s Lanfine), 946s 902 (946s Oakland), 946s 903 (946s Oakland) Cutover Bkr/MOD status, Commission new LTO/RAS 204 A/B - Lanfine/Oakland  
ATCO 13-Nov-26 10:00 14-Nov-26 17:00 31 Hours
Continuous
959s 901T (959s Lanfine), 959s 904 (959s Lanfine), 959s 919 (959s Lanfine), 959s 701 (959s Lanfine), 959s 706 (959s Lanfine) Cutover MOD status, Commission inputs to RAS 204 A/B  
ATCO 23-Nov-26 10:00 23-Nov-26 17:00 7 Hours
Continuous
959s 904 (959s Lanfine) Cutover and Commission Bkr 904 status to RAS 204 A/B  
ATCO 24-Nov-26 10:00 24-Nov-26 17:00 7 Hours
Continuous
959s 919 (959s Lanfine) Cutover and Commission Bkr 919 status to RAS 204 A/B  
ATCO 25-Nov-26 10:00 25-Nov-26 17:00 7 Hours
Continuous
959s 920 (959s Lanfine) Cutover and Commission Bkr 919 status to RAS 204 A/B  
EPCOR 27-Nov-26 07:00 18-Dec-26 17:00 21.42 Days
Continuous
EP 805s J2407 (EP 805s Jasper) Jasper: J2407 Replacement LCR  
ALTALINK 16-Dec-26 10:00 16-Dec-26 14:00 4 Hours
Continuous
250p 1 (250p Bighorn Plant) maintenance  
ALTALINK 17-Dec-26 10:00 17-Dec-26 14:00 4 Hours
Continuous
250p 2 (250p Bighorn Plant) maintenance  
ALTALINK 23-Dec-26 23:30 24-Dec-26 02:30 3 Hours
Continuous
62s 1 (62s Brazeau Plant) maintenence  
ALTALINK 24-Dec-26 03:30 24-Dec-26 06:30 3 Hours
Continuous
62s 2 (62s Brazeau Plant) maintenence  
EPCOR 04-Jan-27 07:00 12-Feb-27 17:00 39.42 Days
Continuous
EP 805s J2401 (EP 805s Jasper) Jasper: J2401 Replacement LCR  
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.
 
EPCOR 15-Feb-27 07:00 19-Feb-27 17:00 4.42 Days
Continuous
EP 805s J2403 (EP 805s Jasper) Jasper: J2403 Replacement LCR  
EPCOR, ALTALINK 19-Feb-27 07:00 05-Mar-27 17:00 14.42 Days
Continuous
EP 805s J2404 (EP 805s Jasper), EP 805s J2403 (EP 805s Jasper), EP 805s J2408 (EP 805s Jasper), 805s C1 (805s Jasper), 1044L (EP 805s Jasper - 816s Petrolia) 1044L/Jasper: J2403 Replacement LCR  
EPCOR 05-Mar-27 07:00 26-Mar-27 17:00 21.38 Days
Continuous
EP 805s J2403 (EP 805s Jasper) Jasper: J2403 Replacement LCR  
ATCO 08-Mar-27 10:00 17-Mar-27 17:00 9.25 Days
Continuous
9L24 (946s Oakland - 959s Lanfine), 959s 906 (959s Lanfine), 959s 905 (959s Lanfine), 946s 902 (946s Oakland), 946s 903 (946s Oakland) Replace A/B protection relays at 959S Lanfine and 946S Oakland
Cut in and reroute 9L24
Connect new 9LA24 T-tap
Commission Telecom and Protection to new 1072S Rose Lynn substation
 
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 22-Mar-27 09:00 25-Mar-27 17:00 3.33 Days
Continuous
2091s 704 (2091s Thornton) AESO project P2716 - cut over new SEL 2440 wiring at 2091S, relay programming, commission DTT and LTO from 2103S Pakenham  
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  
SUNCOR 06-Apr-27 09:00 16-Apr-27 20:00 10.46 Days
Continuous
29EDD-34 29PT-112 (29EDD-34), 29EDD-34 29-752-121 (29EDD-34), 29EDD-34 29PS-68 (29EDD-34), 29EDD-34 29PS-67 (29EDD-34), 29EDD-34 29PS-66 (29EDD-34), 29EDD-34 29PS-65 (29EDD-34), 29EDD-34 29PS-225 (29EDD-34), 29EDD-34 29PS-230 (29EDD-34), 29EDD-34 29-952-141 (29EDD-34), 29EDD-34 29-952-131 (29EDD-34), 29EDD-34 29-952-111 (29EDD-34) 29EDD34;29PT-112 & 29PP-24 SYSTEM;PM
This will Place 29EDD-34 on one 260 kV bus and drop 29PL7-1
 
ATCO 12-Apr-27 10:00 19-Apr-27 17:00 7.29 Days
Continuous
7L22 (790s Poplar Hill - 7L88 tap) Cut open 7L22, connect new line section to new 2061S Dobbs
7L22/21B relay upgrades at 790S Poplar Hill and 811S Clairmont Lake
On completion energize new 2061S Dobbs substation
 
SUNCOR 14-Apr-27 14:00 23-Apr-27 18:00 9.17 Days
Continuous
29EDD-65 29PT-0257 (29EDD-65), 29EDD-65 29-952-4812 (29EDD-65), 29EDD-65 29-952-4813 (29EDD-65), 29EDD-71 752-4624 (29EDD-71), 29EDD-71 752-4623 (29EDD-71), 29PL7-4 (29EDD-65 - 29EDD-71) Firebag: 29EDD65;29PT-257 & 29PL7-4 SYSTEM, 29EDD65 ;29PT-260 & 29PL7-4 SYSTEM, 29EDD71 29PT-241 & 29PL7-4  
ATCO 03-May-27 09:00 17-May-27 17:30 14.35 Days
Continuous
2075s T11 (2075s Newell) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 14.35 Days
Continuous
2029s T11 (2029s Heathfield) Annual EATL outage at 2075s & 2029s.  
ATCO 03-May-27 09:00 17-May-27 17:30 14.35 Days
Continuous
13L50 (2029s Heathfield - 2075s Newell) Annual EATL outage at 2075s & 2029s.
**1218 IS NOT THE ISOALTION. ATCO SENT AESO OF REQUIRED ISOLATIONS BACK IN MAY 2024 TO UPDATE 2029S AND 2075S ISOLATIONS FOR 13L50 OUTAGES**
 
ATCO 03-May-27 10:00 06-May-27 17:00 3.29 Days
Continuous
7L22 (811s Clairmont Lake - 7L88 tap) 7L22/21B relay upgrade at 811S Clairmont Lake
Upon completion new 2061S Dobbs substation ready to energize
 
SUNCOR 04-May-27 09:00 14-May-27 20:00 10.46 Days
Continuous
29EDD-34 29PS-214 (29EDD-34), 29EDD-34 29-952-113 (29EDD-34), 29EDD-34 29PS-215 (29EDD-34), 29EDD-34 29PS-213 (29EDD-34) 29EDD34;29PL9-13 SYSTEM;PM 5y,10y  
SUNCOR 05-May-27 14:00 14-May-27 18:00 9.17 Days
Continuous
29EDD-65 29PT-0236 (29EDD-65), 29EDD-65 29-952-4823 (29EDD-65), 29EDD-65 29-952-4822 (29EDD-65), 29EDD-71 752-4634 (29EDD-71), 29EDD-71 752-4633 (29EDD-71), 29PL7-3 (29EDD-65 - 29EDD-71) Firebag: 29EDD65;29PT-236 & 29PL7-3 SYSTEM, 29EDD65;29PT-250&29PL7-3 SYSTEM, 29PT-246 SYSTEM;29EDD71  
ATCO 10-May-27 10:00 11-May-27 17:00 31 Hours
Continuous
7L03 (749s Flyingshot Lake - 7L09 tap) Cutover and commission RAS analogs and LTO to 790S Poplar Hill RAS Hub  
ATCO 12-May-27 10:00 13-May-27 17:00 31 Hours
Continuous
7L03 (731s Elmworth - 7L09 tap) Cutover and commission LTO to 790S Poplar Hill RAS Hub  
ATCO 14-May-27 10:00 15-May-27 17:00 31 Hours
Continuous
7L69 (731s Elmworth - 815s Goodfare) Cutover and commission LTO to 790S Poplar Hill RAS Hub  
ATCO 16-May-27 10:00 17-May-27 17:00 31 Hours
Continuous
7L07 (790s Poplar Hill - 815s Goodfare) Cutover and commission LTO to 790S Poplar Hill RAS Hub  
SUNCOR 01-Jun-27 08:00 10-Jun-27 17:00 9.38 Days
Continuous
635EDD-1000 635-752-635PT-1000 (635EDD-1000), 635EDD-1000 635PT-1000 (635EDD-1000) FH - Maintenance on Transformer, associated breakers, other equipment in isolation boundary and protection system testing.  
SUNCOR 01-Jun-27 09:00 11-Jun-27 20:00 10.46 Days
Continuous
29EDD-94 407T (29EDD-94 Voyageur), 29EDD-94 29-952-9705 (29EDD-94 Voyageur), 29EDD-94 29PS-393 (29EDD-94 Voyageur), 29EDD-94 29PS-392 (29EDD-94 Voyageur), 29EDD-94 29-952-9704 (29EDD-94 Voyageur), 29EDD-94 29PS-400 (29EDD-94 Voyageur) 29EDD94;29PT-407 SYSTEM;PM 5y,10y  
SUNCOR 11-Jun-27 08:00 20-Jun-27 17:00 9.38 Days
Continuous
635EDD-1000 635-752-635PT-1001 (635EDD-1000), 635EDD-1000 635PT-1001 (635EDD-1000) FH - Maintenance on Transformer, associated breakers, other equipment in isolation boundary and protection system testing.  
SUNCOR 15-Jun-27 09:00 25-Jun-27 20:00 10.46 Days
Continuous
29EDD-94 406T (29EDD-94 Voyageur), 29EDD-94 29-952-9702 (29EDD-94 Voyageur), 29EDD-94 29PS-388 (29EDD-94 Voyageur), 29EDD-94 29PS-389 (29EDD-94 Voyageur), 29EDD-94 29PS-399 (29EDD-94 Voyageur) 29EDD94;29PT-406 SYSTEM;PM 5y,10y  
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  
ATCO 08-Nov-27 09:00 11-Nov-27 17:00 3.33 Days
Continuous
ALC02L (409s Shell Scotford - 879s Upgrader) Install new Deadend corner structure on ALC02L  
ATCO 08-Nov-27 09:00 11-Nov-27 17:00 3.33 Days
Continuous
ALC01L (408s Air Liquide Scotford - 409s Shell Scotford) Install new Deadend corner structure on ALC02L.  
ATCO 06-Mar-28 10:00 22-Mar-28 16:00 16.21 Days
Continuous
826s 903 (826s Marguerite Lake), 826s 907 (826s Marguerite Lake), 826s 901T (826s Marguerite Lake) Expand 240kV ring bus for new 9L42 line  
ATCO 13-Mar-28 10:00 16-Mar-28 17:00 3.29 Days
Continuous
9L939 (77s Sagitawah - 809s Louise Creek) Cut over 9L939 to temp bypass structures to allow for installation of new deadend corner towers. These are required to make the final connections to the new 2105S Jackson substation  
ATCO 17-Mar-28 10:00 17-Apr-28 17:00 31.29 Days
Continuous
9L938 (77s Sagitawah - 809s Louise Creek) Install foundations (TBD assume concrete), assemble and erect new Q-towers 9L938/9L939-155A and 9L938/9L939-156A in existing ROW centreline. Daily outage until such a time as the new towers begin to encroach on 9L938.  
ATCO 18-Apr-28 10:00 25-Apr-28 17:00 7.29 Days
Continuous
9L938 (77s Sagitawah - 809s Louise Creek) Open 9L938 conductors, complete assembly and connect to the new Q-Towers 9L938/9L939-155A and 9L938/9L939-156A, string to 2105S Jackson deadend and terminate.
Relabel 9L938 segment from 809S Louise Creek to 2105S Jackson to 9L140.
 
ATCO 01-May-28 10:00 04-May-28 17:00 3.29 Days
Continuous
9L939 (77s Sagitawah - 809s Louise Creek) Disconnect 9L939 conductors from temp structure 9L939 -155A - 155E reconnect to existing structures 9L938/9L939-156 and 9L938/9L939-155, connect to the new Q-Towers 9L938/9L939-155A and 9L938/9L939-156A, string to 2105S Jackson deadend and terminate.
Relabel 9L939 segment from 809S Louise Creek to 2
 
ATCO 08-May-28 09:00 10-Jul-28 17:00 63.33 Days
Continuous
959s 240kV Bus 900BS2 (959s Lanfine) GOI on 9L141 until line terminated into 1162S Fair Acres and ready to energize  
ATCO 08-May-28 09:00 10-Jul-28 17:00 63.33 Days
Continuous
959s 240kV Bus 900BS2 (959s Lanfine) GOI on 902/903 until line terminated and 1162S Fair Acres ready to energize  
ATCO 09-May-28 10:00 13-May-28 17:00 4.29 Days
Continuous
9L02 (809s Louise Creek - 813s Little Smoky) Install concrete foundations for new structures 9L02/320A, 320H in preparation to cut into 9L02 and convert to a t-tap.  
ATCO 15-May-28 09:00 17-May-28 17:00 2.33 Days
Continuous
959s 240kV Bus 900BS1 (959s Lanfine) Connect new bus from new 902B to existing switch 901A to add new line 9L141,
Cutover and commission 900PT1 ccts to new 9L141 relays
 
ATCO 18-May-28 09:00 20-May-28 17:00 2.33 Days
Continuous
959s 240kV Bus 900BS2 (959s Lanfine) Connect new bus from new Bkr 903 to existing switch 903B to add new line 9L141,
Cutover and commission 900PT2 ccts to new 9L141 relays
 
ATCO 29-May-28 09:00 08-Jun-28 17:00 10.33 Days
Continuous
9L24 (946s Oakland - 959s Lanfine) Cutover and commission 905/906 CT's, 9L24PT ccts to new RAS 241 SEL 451A/B relays @ 959S Lanfine and update relay settings for RAS 241 and SCADA inputs @946S Oakland.  
ATCO 19-Jun-28 10:00 30-Jun-28 16:00 11.25 Days
Continuous
9L20 (755s Cordel - 766s Nevis)
Install concrete foundations at 9L20 Structure 69 for new T-Tap connection
 
ATCO 26-Jun-28 10:00 10-Jul-28 17:00 14.29 Days
Continuous
9L02 (809s Louise Creek - 813s Little Smoky) Cut into 9L02 and connect new t-tap structures for 9LA02.
9L02-21A and 21B relay upgrades at 809S Louise Creek and 813S Little Smoky. Implement RAS
Energize new line 9LA02 and 884S Magpie substation (UK Solar LS1)
 
ATCO 31-Jul-28 10:00 15-Aug-28 16:00 15.25 Days
Continuous
766s 901 (766s Nevis), 9L20 (755s Cordel - 766s Nevis), 755s 906 (755s Cordel), 755s 901 (755s Cordel)
Cutover new 9L20 line section, terminate 9LA20 at customer substation. Install new line protection relays
 

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: 2026-02-26   12:38:35


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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