Alberta Electric System Operator
System Co-ordination Plan
2026-04-18 to 2026-04-24
Approved Outages

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From To Owner Type Element Scheduled Activity Date/Time Comments Interconnection
26-Jul-24 10:00 31-Jul-26 16:00 ATCO Outage 826s 504R (826s Marguerite Lake) emergency removal to replace failed 502R @834S 735.25 Days
Continuous		  
23-Aug-24 13:45 21-May-26 14:29 ALTALINK Outage 157s C1 (157s Lac La Biche) forced outage 636.03 Days
Continuous		  
20-Mar-25 08:00 29-May-26 17:00 ALTALINK Outage 256s C1 (256s Harmattan) forced outage 435.38 Days
Continuous		  
31-Mar-25 07:00 01-May-26 17:00 EPCOR TE Protection & Control (Woodcroft) Woodcroft: protection blocking for merging unit and protection upgrade. 396.42 Days
Continuous		  
12-Sep-25 08:00 19-Jun-26 16:00 ENMAX Outage 33.1TR (SS-33) tap changer refurbishments. soak test required 280.33 Days
Continuous		  
25-Nov-25 17:46 18-Sep-26 18:00 ATCO Outage 876s 901T (876s Brintnell) forced outage oil leaking 296.97 Days
Continuous		  
27-Nov-25 08:30 27-Nov-27 16:30 ALTALINK TE 89s Protection & Control (89s Ellerslie) DSP card replacements on1057L B87/L3 and B240B1 B87/240B1 730.33 Days
Daily		  
04-Jan-26 08:00 02-Sep-26 16:00 SUNCOR Outage 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 241.29 Days
Continuous		  
12-Jan-26 07:00 03-Jul-26 17:00 EPCOR TE 330p Protection & Control (330p Genesee) protect blocking, annual relay maintenance and password changes 172.38 Days
Continuous		  
12-Jan-26 07:00 01-May-26 17:00 EPCOR TE Protection & Control (Rossdale) protection blocking, relay maintenance 109.38 Days
Continuous		  
17-Jan-26 11:00 30-Apr-26 17:00 BHE Canada Outage 120s C2 (120s Picture Butte) forced outage 103.21 Days
Continuous		  
21-Jan-26 08:00 30-Oct-26 16:00 ENMAX Outage 5.7TR (SS-5) 25kV switchgear replacement 282.29 Days
Continuous		  
03-Feb-26 09:00 30-Jun-26 17:00 ATCO TE 972s RTU/SCADA (972s Tinchebray) config changes needed throughout the CETO project 147.29 Days
Continuous		  
09-Feb-26 09:00 26-Jun-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) block all 50BF protection until cutovers and associated commissioning are complete 137.29 Days
Continuous		  
06-Mar-26 17:00 13-Nov-26 17:00 EPCOR Outage T1 (Woodcroft) woodcroft: TX1 LCR civil 252 Days
Continuous		  
10-Mar-26 10:00 30-Nov-26 17:00 ATCO TE 743s RTU/SCADA (743s Sarah Lake) throughout the course of the project, different apparatus are being replaced, RTU will be blocked prior to download 265.33 Days
Continuous		  
11-Mar-26 13:45 19-Apr-26 16:00 ALTALINK Outage 535s C1 (535s Joffre) breaker maintenance 39.09 Days
Continuous		  
13-Mar-26 16:00 24-Apr-26 17:00 ATCO Outage 7L122 (791s Rainbow Lake - 930s Arcenciel), 791s 701 (791s Rainbow Lake) phase replacement 42.04 Days
Continuous		  
22-Mar-26 13:00 30-Jun-26 17:00 BHE Canada Outage 120s C1 (120s Picture Butte), 120s C2 (120s Picture Butte) forced outage 100.17 Days
Continuous		  
28-Mar-26 12:00 14-May-26 17:00 ATCO TE 833s RTU/SCADA (833s Mariana) updating RTU/station controller configuration during SCADA upgrade project 47.21 Days
Continuous		  
30-Mar-26 08:30 04-May-26 16:30 ALTALINK Outage 62s T1 (62s Brazeau Plant), 62s 1 (62s Brazeau Plant) maintenance 35.33 Days
Continuous		  
06-Apr-26 07:00 01-May-26 17:00 EPCOR Outage 72JM18 (EP 805s Jasper - Meadowlark), T1 (Meadowlark), M721 (Meadowlark), M722 (Meadowlark), EP 805s J722 (EP 805s Jasper), EP 805s JDS29 (EP 805s Jasper), MAB1 (Meadowlark) Meadowlark - T1 LCR demo 25.42 Days
Continuous		  
06-Apr-26 08:00 19-Jun-26 16:00 ALTALINK TE 37s RTU/SCADA (37s North Calder) RTU database updates 74.33 Days
Continuous		  
07-Apr-26 07:00 21-Apr-26 17:00 ALTALINK TE 1012s Protection & Control (1012s Deer Hill) settings changes and testing associated with 685L line splitting 14.42 Days
Continuous		  
07-Apr-26 07:00 21-Apr-26 17:00 ALTALINK TE 397s Protection & Control (397s Benbow) settings changes and testing associated with L3 protection upgrades 14.42 Days
Continuous		  
07-Apr-26 07:00 21-Apr-26 17:00 ALTALINK TE 39s Protection & Control (39s Bickerdike) protection outages required on A21/L1 and B21/L1 (854L) protections for settings changes and testing associated with 685L line splitting 14.42 Days
Continuous		  
07-Apr-26 07:00 21-Apr-26 17:00 ALTALINK TE 397s RTU/SCADA (397s Benbow) alarm/control updates and testing of new L3 protections for the Berland River project 14.42 Days
Continuous		  
07-Apr-26 07:00 21-Apr-26 17:00 ALTALINK TE 1012s RTU/SCADA (1012s Deer Hill) alarm/control updates and testing for the Berland River project 14.42 Days
Continuous		  
07-Apr-26 09:00 21-Apr-26 15:00 ALTALINK Outage 685L (397s Benbow - 1012s Deer Hill), 614L (397s Benbow - 328s Pine Creek), 1012s 685 (1012s Deer Hill), 397s 685 (397s Benbow), 328s 614 (328s Pine Creek), 328s 685 (328s Pine Creek) split 685L into new 614L and 685L for in/out @ 328s, energize 328s614, 328s685, & 328s 138kV Bus 1, return temporary phase swap back to normal at flying tap location at 1012s
14.25 Days
Continuous		  
07-Apr-26 10:00 20-Apr-26 16:00 ATCO Outage 743s 702T (743s Sarah Lake), 743s 706 (743s Sarah Lake), 743s 502 (743s Sarah Lake) 743S rebuild - replace breaker 502 13.25 Days
Continuous		  
08-Apr-26 07:00 10-May-26 17:00 ALTALINK, ALPAC IO 796L (282s Grassland - 796AL tap) note for area assessments 32.42 Days
Continuous		  
08-Apr-26 09:00 22-Apr-26 17:00 ATCO Outage 833s 701T (833s Mariana), 833s 701TCS (833s Mariana) full protection and SCADA upgrades, replacement of battery bank, charger, and addition of BMS
 14.33 Days
Continuous		  
09-Apr-26 17:01 13-May-26 07:00 EPCOR Outage 72RW3 (Rossdale - Woodcroft), RW727 (Rossdale) termination rebuild at the Woodcroft end 33.58 Days
Continuous		  
12-Apr-26 16:00 19-Apr-26 12:00 ALTALINK Outage 525s T1 (525s Carseland) 525sT1 doble test, maintenance, PT4 testing 6.83 Days
Continuous		  
13-Apr-26 07:00 29-May-26 17:00 EPCOR Outage 805s T4 (805s Jasper) bushing replacement and fan repair 46.42 Days
Continuous		  
13-Apr-26 07:00 20-Apr-26 18:00 ALTALINK Outage 87s 240kV West Bus (87s Gaetz), 914L (86s Bigstone - 87s Gaetz), 87s T1 (87s Gaetz), 87s 2352 (87s Gaetz), 87s 1252 (87s Gaetz), 87s 1352 (87s Gaetz), 87s 1552 (87s Gaetz), 87s 1752 (87s Gaetz) closing open point 'I' and creating second permanent bus cut between 87s26 and 87s 240 kV west bus 7.46 Days
Continuous		  
13-Apr-26 08:00 24-Apr-26 15:00 CMH TE MHS-7 Protection & Control (MHS-7 Brier Park) preventative maintenance 11.29 Days
Continuous		  
13-Apr-26 09:00 18-Apr-26 15:00 ALTALINK, BHE, BHE Canada Outage MATL (120s Picture Butte - Montana), 120s 1052 (120s Picture Butte), PDB2401 (BHE Hay Lake), PDB2405 (BHE Hay Lake) align with 1201L outage 5.25 Days
Continuous		 AB-MATL
13-Apr-26 09:00 23-Apr-26 17:00 BCH RB 2L294 (BCH A. A. Lambert - BCH Cranbrook), 2L294 (BCH A. A. Lambert - BCH Nelway) ANRP for tree removal 10.33 Days
Daily		 AB-BC
13-Apr-26 09:00 21-May-26 10:00 ALTALINK Outage 157s C1 (157s Lac La Biche) replace breaker and disconnect switch 38.04 Days
Continuous		  
13-Apr-26 11:25 18-Apr-26 15:00 ALTALINK, BCH Outage Path 1 (AIES Islanding), 1201L (520s Bennett - BCH Cranbrook), 5L94 (BCH Cranbrook - 520s Bennett), 520s 552 (520s Bennett), 520s 12 (520s Bennett), 5D25 (BCH Cranbrook) BC hydro outage for insulator replacement program - 500 kV switchyard work 5.15 Days
Continuous		 AB-BC
13-Apr-26 11:25 18-Apr-26 15:00 ALTALINK, BCH Outage 799s 786W (799s Coleman), 786L (799s Coleman - BCH Natal) 1201L is out of service 5.15 Days
Continuous		 AB-BC
13-Apr-26 11:25 18-Apr-26 15:00 ALTALINK, BCH Outage 48s 887X (48s Pocaterra), 887L (48s Pocaterra - 978s BCH Britt Creek) 1201L is out of service 5.15 Days
Continuous		 AB-BC
14-Apr-26 07:00 27-Apr-26 17:00 EPCOR Outage 330p 500kV Bus 2 (330p Genesee), 330p 12TC2 (330p Genesee), 330p 1209 (330p Genesee), 330p 1206 (330p Genesee), 330p 1203 (330p Genesee), 330p 1211 (330p Genesee), 330p 1215 (330p Genesee), 330p 12TC2D (330p Genesee), 330p 809 (330p Genesee) Genesee 500 kV bus 2, POW project installation 13.42 Days
Continuous		  
14-Apr-26 07:00 20-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay testing 6.44 Days
Continuous		  
14-Apr-26 07:00 20-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay testing 6.44 Days
Continuous		  
14-Apr-26 07:00 20-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay testing 6.44 Days
Continuous		  
15-Apr-26 07:15 21-Apr-26 16:45 ALTALINK Outage 790L (434s Stony Plain - 790AL tap), 434s 790 (434s Stony Plain) transmission line maintenance 6.4 Days
Continuous		  
16-Apr-26 07:00 29-Apr-26 17:00 EPCOR Outage 330P GT7 (330p Genesee), 330p 1215 (330p Genesee), 330p 1214 (330p Genesee) POW project installation 13.42 Days
Continuous		  
16-Apr-26 07:00 29-Apr-26 17:00 EPCOR Outage 330P GT7 (330p Genesee) POW project installation 13.42 Days
Continuous		  
16-Apr-26 11:00 18-Apr-26 16:00 ALTALINK, TRANSCANADA Outage 782L (269s Wyndham - 525s Carseland), 525s 48 (525s Carseland), 269s 501 (269s Wyndham), 269s 502 (269s Wyndham), 269s 551 (269s Wyndham), 269s 552 (269s Wyndham) prevent unintended trips 2.21 Days
Continuous		  
17-Apr-26 08:00 28-Apr-26 16:00 ENMAX Outage 3.82L (SS-3 - SS-8), 3B138-3.82 (SS-3) City of Calgary traffic light rebuild 11.33 Days
Continuous		  
17-Apr-26 08:00 26-Apr-26 16:00 Syncrude Outage 1834 (Syncrude Mildred Lake), 1835 (Syncrude Mildred Lake), Mildred T18 (Syncrude Mildred Lake) T18 6-year maintenance 9.33 Days
Continuous		  
18-Apr-26 07:00 20-Apr-26 17:00 EPCOR RB 1055L (629s Argyll Transfer Station - 816s Petrolia) aerial washing program 2.42 Days
Continuous		  
18-Apr-26 07:00 19-Apr-26 16:00 ATCO Outage 7L137 (768s Rowley - 770s Three Hills), 768s 703 (768s Rowley), 770s 702 (770s Three Hills) sample climbing inspection, 160 poles to climb and inspect on 7L137 1.38 Days
Daily		  
18-Apr-26 08:00 18-Apr-26 18:00 ENMAX, ALTALINK Outage 50L (44s Bearspaw Plant - SS-21), 21.2TR (SS-21), 21.1C (SS-21), 60s50 (SS-21), 21MD138-21.2TR (SS-21) HV switch maintenance 21SW90, spring substation washing, reversing switch check - 21.2-TC 10 Hours
Continuous		  
18-Apr-26 08:00 18-Apr-26 16:00 ALTALINK TE 321s RTU/SCADA (321s Al Rothbauer) split the existing SCADA VLAN from 1 to 1 and 2
8 Hours
Continuous		  
18-Apr-26 09:00 18-Apr-26 17:00 ENMAX, ALTALINK IO 50L (44s Bearspaw Plant - SS-21), 44s 50X (44s Bearspaw Plant) HV switch maintenance 21SW90, spring substation washing, reversing switch check - 21.2-TC 8 Hours
Continuous		  
18-Apr-26 09:30 20-Apr-26 17:00 ALTALINK, EPCOR Outage 1056L (89s Ellerslie - 629s Argyll Transfer Station), 240BA2 (629s Argyll Transfer Station - 814s Bellamy), 814s BDS19 (814s Bellamy) aerial washing program 2.31 Days
Continuous		  
18-Apr-26 09:30 20-Apr-26 17:00 ALTALINK, EPCOR IO 1056L (89s Ellerslie - 629s Argyll Transfer Station) aerial washing program
2.31 Days
Continuous		  
19-Apr-26 08:00 19-Apr-26 18:00 ENMAX Outage 1.81L (SS-1 - SS-20), 20.1TR (SS-20), 20B138-1.81 (SS-20), 20BA8-20.1TR (SS-20), 20BB8-20.1TR (SS-20), SW83 (SS-20), 20MD138-20.1TR (SS-20) spring substation washing, power factor test - 20PT138-Z31, breaker SF6 gas sample - 20B138-1.81 10 Hours
Continuous		  
20-Apr-26 07:00 24-Apr-26 17:00 EPCOR Outage T2 (Kennedale), K723 (Kennedale), K722 (Kennedale), KAB2 (Kennedale) transformer T2 relay maintenance 4.42 Days
Continuous		  
20-Apr-26 07:00 26-Apr-26 17:00 EPCOR Outage T2 (Strathcona), S722 (Strathcona), S723 (Strathcona), SAB2 (Strathcona) transformer T2 doble and disconnect maintenance 6.42 Days
Continuous		  
20-Apr-26 07:00 01-May-26 17:00 EPCOR Outage T4 (Rossdale), R724 (Rossdale), RR729 (Rossdale), RAB4 (Rossdale) transformer T4 zone doble, repairs 11.42 Days
Continuous		  
20-Apr-26 07:00 23-Apr-26 17:00 ALTALINK TE 87s RTU/SCADA (87s Gaetz) SCADA RTU configuration update for CETO project 3.42 Days
Continuous		  
20-Apr-26 07:00 30-Apr-26 18:00 ALTALINK RB 974L (39s Bickerdike - 310p Sundance) transmission line maintenance 10.46 Days
Continuous		  
20-Apr-26 07:00 30-Apr-26 18:00 ALTALINK RB 973L (39s Bickerdike - 310p Sundance) transmission line maintenance 10.46 Days
Continuous		  
20-Apr-26 07:00 23-Apr-26 17:00 ALTALINK TE 275s RTU/SCADA (275s Jenner) update RTU configuration for 944L line protections 3.42 Days
Continuous		  
20-Apr-26 07:00 23-Apr-26 17:00 ALTALINK TE 132s RTU/SCADA (132s Ware Junction) update RTU configuration 944L line protection 3.42 Days
Continuous		  
20-Apr-26 07:00 23-Apr-26 17:00 ALTALINK TE 1080s RTU/SCADA (1080s Raptor) RTU configuration update for 944L protection 3.42 Days
Continuous		  
20-Apr-26 07:00 08-May-26 17:00 EPCOR TE Protection & Control (Kennedale) protection blocking - relay maintenance 18.42 Days
Continuous		  
20-Apr-26 07:00 08-May-26 17:00 EPCOR TE 72CN10 (987s Clover Bar - Namao) protection blocking - MPLS upgrade 18.42 Days
Continuous		  
20-Apr-26 07:00 08-May-26 17:00 EPCOR TE 72CH11 (987s Clover Bar - EP Hardisty) protection blocking - MPLS upgrade 18.42 Days
Continuous		  
20-Apr-26 07:00 08-May-26 17:00 EPCOR TE 72CH9 (987s Clover Bar - EP Hardisty) protection blocking - MPLS upgrade 18.42 Days
Continuous		  
20-Apr-26 07:00 08-May-26 17:00 EPCOR TE 72KN23 (Kennedale - Namao) protection blocking - MPLS upgrade 18.42 Days
Continuous		  
20-Apr-26 07:15 23-Apr-26 16:45 ALTALINK Outage 898L (37s North Calder - 92s Viscount), 37s 898 (37s North Calder), 92s 898 (92s Viscount) protection upgrade (37s898) 3.4 Days
Continuous		  
20-Apr-26 08:00 30-Apr-26 16:00 ALTALINK TE 87s Protection & Control (87s Gaetz) setting and wiring change 10.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ATCO RB 7L60 (780s Lubicon - 827s Cranberry Lake) walk up and climbing inspection 3.33 Days
Continuous		  
20-Apr-26 08:00 20-Apr-26 16:00 ENMAX Outage 25B240-D133 (SS-25) HV breaker maintenance, SF6 gas sample 8 Hours
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ALTALINK TE 1080s Protection & Control (1080s Raptor) protection outages on 944AL A and B protection relays to test new SCN point for differential protection fail 3.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ALTALINK TE 132s Protection & Control (132s Ware Junction) protection outage on 944L A and B line protection relays to test new differential protection fail SCN points 3.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ALTALINK TE 275s Protection & Control (275s Jenner) 944L A and B line protection outages, testing of new differential protection fail SCN point 3.33 Days
Continuous		  
20-Apr-26 08:00 21-Apr-26 17:30 REDDEER Outage 217s T1 (217s North Red Deer) transformer protection relay replacement 1.4 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ENMAX Outage 8.1TR (SS-8) transformer power factor test, secondary cable test , transformer maintenance, relay fault pressure test, reversing switch check - 8.1-TC 3.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ALTALINK TE 37s Protection & Control (37s North Calder) relay settings change 3.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ALTALINK TE 92s Protection & Control (92s Viscount) relay settings change 3.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 16:00 ALTALINK TE 92s RTU/SCADA (92s Viscount) RTU database update 3.33 Days
Continuous		  
20-Apr-26 08:00 23-Apr-26 17:00 SUNCOR Outage 635EDD-1001 635PT-1037 (635EDD-1001) transformer's second side equipment maintenance 3.38 Days
Continuous		  
20-Apr-26 09:00 27-Apr-26 17:00 ATCO, PWLP TE 973s Protection & Control (973s Lanes Lake), 973s RTU/SCADA (973s Lanes Lake) 9LA93 protection updates and testing 7.33 Days
Continuous		  
20-Apr-26 09:00 27-Apr-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) 9L93 protection setting changes including updates at 973s and 615s 7.33 Days
Continuous		  
20-Apr-26 09:00 20-Apr-26 11:00 ATCO TE ATCO Telecom Equipment, 2049s RTU/SCADA (2049s Kettle River) telecom upgrade 2 Hours
Continuous		  
20-Apr-26 09:00 24-Apr-26 17:00 BCH Outage 5L98 (BCH Nicola - BCH Vaseux Lake) replace emergent broken insulators 4.33 Days
Continuous		 AB-BC
20-Apr-26 09:00 08-May-26 17:00 BCH Outage 5L98 (BCH Nicola - BCH Vaseux Lake) replace spacer damper and insulator, BC maintenance does not affect the Alberta ATC 18.33 Days
Continuous		 AB-BC
20-Apr-26 09:00 23-Apr-26 17:00 BCH TE Protection & Control (BCH Natal) installing new cards in the NTLDCS002 SY DACS 3.33 Days
Continuous		 AB-BC
20-Apr-26 10:00 24-Apr-26 16:00 ATCO TE 951s RTU/SCADA (951s Thickwood Hills) configuration changes, computer patching 4.25 Days
Continuous		  
20-Apr-26 11:00 23-Apr-26 15:00 ATCO Outage 6L02 (765s Mannix Mine - 873s Marion Lake) climbing inspection on 6L02 3.17 Days
Continuous		  
20-Apr-26 11:30 23-Apr-26 17:00 ALTALINK TE 379s Protection & Control (379s Shell Canada Waterton) DSP card replacement and firmware upgrades on GE relays 3.23 Days
Continuous		  
20-Apr-26 12:00 24-Apr-26 17:00 ATCO Outage 813s SVC (813s Little Smoky), 813s 719 (813s Little Smoky) SVC maintenance 4.21 Days
Continuous		  
20-Apr-26 13:00 20-Apr-26 17:30 ATCO Trans Test 755s 901 (755s Cordel) PRC-005 - trip and close coil testing 4.5 Hours
Continuous		  
20-Apr-26 16:00 22-Apr-26 06:00 ALTALINK TE AltaLink Telecom Equipment telemetry outage 1.58 Days
Continuous		  
21-Apr-26 07:00 21-Apr-26 17:00 EPCOR TE APS# 172 Garneau - Meadowlark Reconfiguration Scheme RAS - protection blocking, alarm repair 10 Hours
Continuous		  
21-Apr-26 07:30 21-Apr-26 17:30 ALTALINK TE 17s Protection & Control (17s Benalto) setting changes in A77/1144AIS relay to split channel fail alarms 10 Hours
Continuous		  
21-Apr-26 07:30 21-Apr-26 14:00 ATCO Outage 6L15 (763s Hanna - 775s Sullivan Lake), 763s 602 (763s Hanna), 775s 601 (775s Sullivan Lake) splice conductor on span 6L15-151 6.5 Hours
Continuous		  
21-Apr-26 08:00 21-Apr-26 16:00 ALTALINK Outage 186s T1 (186s Dry Creek) 186s27 and 186s12 cooper cutout replacement 8 Hours
Continuous		  
21-Apr-26 08:00 23-Apr-26 08:00 ALTALINK Outage 244s C1 (244s Bowmanton) replace secondary control fuses in breaker control cabinet
2 Days
Continuous		  
21-Apr-26 08:00 23-Apr-26 08:00 ALTALINK Outage 244s C2 (244s Bowmanton) replace control fuses within breaker secondary cabinet

2 Days
Continuous		  
21-Apr-26 08:00 23-Apr-26 08:00 ALTALINK Outage 244s C3 (244s Bowmanton) replace secondary control fuses in breaker control cabinet

2 Days
Continuous		  
21-Apr-26 08:00 21-Apr-26 17:00 ALTALINK TE 40s RTU/SCADA (40s Wetaskiwin), AltaLink Telecom Equipment firmware upgrade on MPLS nodes A and B, firewall upgrade, telecom switch and firewall upgrade

9 Hours
Continuous		  
21-Apr-26 08:00 24-Apr-26 16:00 ALTALINK TE 618s Protection & Control (618s Riverbend) move relay to new city of Lethbridge communication system 3.33 Days
Continuous		  
21-Apr-26 08:00 24-Apr-26 17:00 Lethbridge TE 111s Protection & Control (111s Coalbanks), 674s Protection & Control (674s Bowron) protection outages on 111s and 674s 725LE 'A' & 'B' protections to transfer TPR (teleprotection) circuits from existing JMUX to new SEL ICON 3.38 Days
Continuous		  
21-Apr-26 08:00 22-Apr-26 16:00 ENMAX Outage 833L (SS-2 - SS-12), 12.2TR (SS-12), 12B138-833L (SS-12), SW83 (SS-12), 12MD138-12.2TR (SS-12) hw sw maintenance SW81, SW82, SW83, MD-12.2TR,reversing switch check - 12.2-TC, 12B138-833L - gear box top up 1.33 Days
Continuous		  
21-Apr-26 08:00 21-Apr-26 16:00 ALTALINK TE 40s RTU/SCADA (40s Wetaskiwin) split the existing SCADA VLAN from 1 to 1 and 2 8 Hours
Continuous		  
21-Apr-26 08:00 21-Apr-26 17:00 ALTALINK TE 17s RTU/SCADA (17s Benalto) RTU outage to upgrade RTU firmware and test new alarms from A77/1144AIS relay 9 Hours
Continuous		  
21-Apr-26 08:00 23-Apr-26 14:00 ATCO RB 7L137 (768s Rowley - 770s Three Hills) climbing inspection on 7L137 2.25 Days
Continuous		  
21-Apr-26 08:00 21-Apr-26 17:00 ALTALINK Outage 408L (51s Wainwright - 252s Jarrow), 51s 408N (51s Wainwright), 252s 408 (252s Jarrow) 138 kV breaker maintenance 9 Hours
Continuous		  
21-Apr-26 08:00 22-Apr-26 16:00 ENMAX TE Protection & Control (SS-162) 162 sub 138 kV Z34 A and B (86) lockout relay and (87) bus differential protection outage - relays, lockout testing 86-Z34-A, 86-Z34-B 1.33 Days
Daily		  
21-Apr-26 08:00 21-Apr-26 17:00 ALTALINK RB 202L (58s Edson - 178s Cynthia) inspecting a woodpecker cavity on structure 799 9 Hours
Continuous		  
21-Apr-26 08:30 23-Apr-26 16:00 ALTALINK TE 394s RTU/SCADA (394s Empress) replace T3 metering equipment 2.31 Days
Continuous		  
21-Apr-26 08:30 21-Apr-26 16:00 ALTALINK TE 252s Protection & Control (252s Jarrow) relay maintenance 7.5 Hours
Continuous		  
21-Apr-26 09:00 26-Apr-26 17:00 ATCO, CapitalPower, PWLP Outage 9L93 (972s Tinchebray - 9L93 tap), 9LA93 (973s Lanes Lake - 9L93 tap), 972s 904 (972s Tinchebray), 972s 905 (972s Tinchebray), 615s 52T1 (615s Halkirk), 973s 52-240 (973s Lanes Lake), 615s 9L93D2 (615s Halkirk), 972s 9L93D1 (972s Tinchebray), 973s 89-L1 (973s Lanes Lake) cutover and commission 9L93 protection 5.33 Days
Continuous		  
21-Apr-26 09:00 21-Apr-26 16:00 ATCO TE ATCO Telecom Equipment, 886s RTU/SCADA (886s Updike) Updike_S-telecom- investigate the Updike to Saskatoon radio link 7 Hours
Continuous		  
21-Apr-26 09:00 23-Apr-26 16:00 ALTALINK Outage 394s T3 (394s Empress), 394s 36 (394s Empress) 394sT3 CT7 replacement, cable repair 2.29 Days
Continuous		  
21-Apr-26 09:00 21-Apr-26 10:00 ATCO TE ATCO Telecom Equipment, 780s RTU/SCADA (780s Lubicon), 869s RTU/SCADA (869s Seal Lake) Otter Lakes NET 1 SAR OS upgrade to V21, then V22
 60 Mins
Continuous		  
21-Apr-26 09:30 21-Apr-26 12:00 ATCO Trans Test 755s 902 (755s Cordel) PRC-005 - trip and close coil testing 2.5 Hours
Continuous		  
21-Apr-26 09:30 21-Apr-26 13:30 ALTALINK Outage 871L (163s Amoco Empress - 341s Sand Hills), 163s 871X (163s Amoco Empress) PRC5 checks 4 Hours
Continuous		  
21-Apr-26 12:31 21-Apr-26 17:30 ALTALINK Outage 87s 252 (87s Gaetz) demo 1252 and 2352 breaker fail trips from the 87s 252 trip chain 4.98 Hours
Continuous		  
21-Apr-26 13:00 21-Apr-26 17:30 ATCO Trans Test 755s 904 (755s Cordel) PRC-005 - trip and close coil testing 4.5 Hours
Continuous		  
21-Apr-26 15:00 06-May-26 09:00 ALTALINK Outage 1182s 138kV Bus 1 (1182s Berland River), 620L (1182s Berland River - 328s Pine Creek), 1182s T1 (1182s Berland River), 1182s C1 (1182s Berland River), 1182s C2 (1182s Berland River), 328s 620 (328s Pine Creek), 1182s 152 (1182s Berland River) complete 620L and energize new 1182s, close 620L ope point 'A', 1182s cap bank testing, soak 1182s T1 for 24 hours, load pickup 14.75 Days
Continuous		  
21-Apr-26 15:00 03-May-26 18:00 ALTALINK IO 1182s 4 (1182s Berland River) complete commissioning on 1182s8 12.13 Days
Continuous		  
22-Apr-26 07:00 22-Apr-26 17:00 ALTALINK Outage 790L (432s Carvel - 790AL tap), 432s 790 (432s Carvel) transmission line maintenance 10 Hours
Continuous		  
22-Apr-26 07:30 22-Apr-26 12:30 ALTALINK Outage 87s 552 (87s Gaetz) demo 87s 1652 and 2352 breaker fail trips from the 87s552 trip chain 5 Hours
Continuous		  
22-Apr-26 08:00 22-Apr-26 17:00 ALTALINK TE 288s RTU/SCADA (288s Wolf Creek), AltaLink Telecom Equipment firmware upgrade on MPLS nodes A and B, firewall upgrade, split the existing SCADA VLAN from 1 to 1 and 2 9 Hours
Continuous		  
22-Apr-26 08:00 22-Apr-26 17:00 ALTALINK, WPLP, TRANSALTA Outage 503L (268s Whitecourt - 323s Whitecourt Power), 268s 503 (268s Whitecourt), 323s 52L (323s Whitecourt Power) work on 323s3 9 Hours
Continuous		  
22-Apr-26 08:00 22-Apr-26 16:00 ALTALINK TE 341s Protection & Control (341s Sand Hills Sub) PRC maintenance on 81/13B1 BE181 871L U/F line protection, perform routine site inspection 8 Hours
Continuous		  
22-Apr-26 08:00 23-Apr-26 17:30 REDDEER Outage 217s T2 (217s North Red Deer) transformer protection relay replacement 1.4 Days
Continuous		  
22-Apr-26 08:00 08-May-26 16:00 ALTALINK TE 328s RTU/SCADA (328s Pine Creek) RTU updates for changes involving 620L P&C equipment 16.33 Days
Continuous		  
22-Apr-26 08:00 08-May-26 16:00 ALTALINK TE 328s Protection & Control (328s Pine Creek) circuit modification and testing involving 620L P&C equipment 16.33 Days
Continuous		  
22-Apr-26 08:00 23-Apr-26 16:00 ENMAX Outage 40.2TR (SS-40) tap changer inspection, reversing switch check, tap changer oil filtration maintenance, oil sampling MT, TC 1.33 Days
Continuous		  
22-Apr-26 08:00 22-Apr-26 18:00 ALTALINK Outage 127s 138kV Bus 1 (127s Bruderheim), 773L (127s Bruderheim - 308s Albchem Beaverhill Creek), 846L (127s Bruderheim - 365s Canadianoxy Astotin Creek), 127s T1 (127s Bruderheim), 365s T1 (365s Canadianoxy Astotin Creek), 127s 773W (127s Bruderheim), 127s 846X (127s Bruderheim), 308s 773E (308s Albchem Beaverhill Creek), 365s 846N (365s Canadianoxy Astotin Creek), 127s 2 (127s Bruderheim), 127s 24 (127s Bruderheim) PRC5 maintenance and first trip, repairing down lead to OHSW on 846L structure 14, re-tightening hardware on 846L structure 16 10 Hours
Continuous		  
22-Apr-26 08:15 22-Apr-26 17:00 ALTALINK Outage 650s 952 (650s Hansman Lake) 240 kV breaker maintenance 8.75 Hours
Continuous		  
22-Apr-26 09:00 22-Apr-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) cutover 901CT and 903CT cores U and V from 9L93 protection to 900BS1 protection and commission
 8 Hours
Continuous		  
22-Apr-26 09:00 22-Apr-26 12:00 ATCO TE ATCO Telecom Equipment, 815s RTU/SCADA (815s Goodfare) radio maintenance 3 Hours
Continuous		  
22-Apr-26 09:00 22-Apr-26 11:00 ATCO RB 7L574 (822s Wolf Lake - 7L574 tap), 7L574 (970s Bourque - 7L574 tap), 7L35 (859s Primrose - 7L35 tap) reclosing turned off on 7L574/7L35 for the duration of this work 1-00516956 2 Hours
Continuous		  
22-Apr-26 09:00 22-Apr-26 11:00 ATCO, CNRL TE 859s RTU/SCADA (859s Primrose) ATCO is performing radio work 2 Hours
Continuous		  
22-Apr-26 09:00 22-Apr-26 18:00 ATCO, ALTALINK RB 9L948 (650s Hansman Lake - 863s Paintearth) 240 kV breaker maintenance
, block reclosing for AltaLink		 9 Hours
Continuous		  
22-Apr-26 09:30 22-Apr-26 17:30 ATCO Outage 755s 903 (755s Cordel) breaker testing 8 Hours
Continuous		  
22-Apr-26 09:30 05-May-26 16:30 ATCO, ALTALINK IO 6L126 (743s Sarah Lake - 515L tap), 126L1 (6L126 tap) 743S Sarah Lake rebuild and replace H-Frame structure and 72 kV switches 13.29 Days
Continuous		  
22-Apr-26 10:00 05-May-26 16:00 ATCO, ALTALINK Outage 743s 72kV Bus 600BS1 (743s Sarah Lake), 6L126 (743s Sarah Lake - 515L tap), 6L96 (735s Swan River - 743s Sarah Lake), 6L11 (743s Sarah Lake - 854s Swan Dive), 743s 705 (743s Sarah Lake), 743s 601 (743s Sarah Lake), 743s 603 (743s Sarah Lake), 743s 604 (743s Sarah Lake), 743s 605 (743s Sarah Lake), 743s 501 (743s Sarah Lake), 735s 604 (735s Swan River) 743S Sarah Lake rebuild, 72 kV bus outage and replace wood H-Frame structure and 72 kV switches 13.25 Days
Continuous		  
22-Apr-26 10:00 22-Apr-26 12:00 ATCO Outage 7L62 (789s Keg River - 797s Kemp River) PRC trip coil testing 2 Hours
Continuous		  
22-Apr-26 12:01 22-Apr-26 14:00 ATCO Outage 7L58 (789s Keg River - 905s Meikle) PRC trip coil testing 119 Mins
Continuous		  
22-Apr-26 12:30 22-Apr-26 17:30 ALTALINK Outage 87s 852 (87s Gaetz) demo 87s 1252 and 2352 breaker fail trips from the 87s852 trip chain 5 Hours
Continuous		  
23-Apr-26 03:30 23-Apr-26 06:30 ALTALINK Outage 62s T2 (62s Brazeau Plant) maintenance 3 Hours
Continuous		  
23-Apr-26 07:00 23-Apr-26 19:00 ALTALINK Outage 404s T1 (404s Peace Butte) 404s T1 maintenance 12 Hours
Continuous		  
23-Apr-26 07:00 23-Apr-26 17:00 EPCOR TE RTU/SCADA (Rossdale) emergency RTU outage, repair label issue and re-commission 10 Hours
Continuous		  
23-Apr-26 07:30 23-Apr-26 12:30 ALTALINK Outage 87s 952 (87s Gaetz) demo 1652 and 2352 breaker fail trips from the 87s952 trip chain 5 Hours
Continuous		  
23-Apr-26 08:00 23-Apr-26 17:00 ALTALINK TE 331s RTU/SCADA (331s Ponoka), AltaLink Telecom Equipment firmware upgrade on MPLS node A, firewall upgrade
9 Hours
Continuous		  
23-Apr-26 08:00 23-Apr-26 16:00 ENMAX, ALTALINK Outage 5s C3 (5s East Calgary), 5s C4 (5s East Calgary) HV switch Maintenance 2-5S7E 8 Hours
Continuous		  
23-Apr-26 08:00 24-Apr-26 16:00 ENMAX Outage 16.63L (SS-16 - SS-36), 36.5TR (SS-36), 16B69-16.63 (SS-16), 36B69-16.63/36.5TR (SS-36) HV breaker maintenance 1.33 Days
Continuous		  
23-Apr-26 08:00 23-Apr-26 16:00 ENMAX, ALTALINK IO 5s C3 (5s East Calgary), 5s C4 (5s East Calgary) ENMAX HV switch maintenance 2-5S7E 8 Hours
Continuous		  
23-Apr-26 08:00 24-Apr-26 16:00 ENMAX Outage 3.82L (SS-3 - SS-8), 3.3TR (SS-3), 3MD138-3.3TR (SS-3), SW83 (SS-3) power factor test - 3PT138-Z31, 3.3TR MD needs adjustments 1.33 Days
Continuous		  
23-Apr-26 08:00 26-Apr-26 17:00 SUNCOR Outage 635EDD-1001 635PT-1036 (635EDD-1001) 635PT-1036 outage for transformer's second side equipment maintenance 3.38 Days
Continuous		  
23-Apr-26 08:00 23-Apr-26 18:00 ATCO IO ATCO Telecom Equipment non redundant firewall replacement 10 Hours
Continuous		  
23-Apr-26 08:00 23-Apr-26 17:00 ATCO IO ATCO Telecom Equipment Vegreville_T(SCC)-Telecom- Vegreville tower upgrading dynamic load rating server 9 Hours
Continuous		  
23-Apr-26 08:01 23-Apr-26 16:00 ALTALINK Trans Test 244s C2 (244s Bowmanton) energize C2 to update SEL protective relay KSET value with real world data 7.98 Hours
Continuous		  
23-Apr-26 09:00 23-Apr-26 16:00 ATCO TE ATCO Telecom Equipment flashcard failure replacement, link facing Whitecourt
 7 Hours
Continuous		  
23-Apr-26 09:00 24-Apr-26 17:00 BCH Outage 5L98 (BCH Nicola - BCH Vaseux Lake) 5CB51 rebuild 1.33 Days
Continuous		 AB-BC
23-Apr-26 09:00 23-Apr-26 16:30 ATCO TE 832s RTU/SCADA (832s Blumenort) SCADA updates for EPSS alarm and control 7.5 Hours
Continuous		  
23-Apr-26 09:00 23-Apr-26 10:00 ATCO TE ATCO Telecom Equipment, 796s RTU/SCADA (796s Nipisi) Nipisi_T-Telecom - upgrading NIPISI sub SAR OS to V21, then V22 60 Mins
Continuous		  
23-Apr-26 09:30 23-Apr-26 16:00 ALTALINK Outage 54s T3 (54s Fort Saskatchewan) 25 kV breaker maintenance 6.5 Hours
Continuous		  
23-Apr-26 10:00 23-Apr-26 14:00 ATCO Outage 789s 705R (789s Keg River) PRC trip coil testing 4 Hours
Continuous		  
23-Apr-26 12:00 23-Apr-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) 9L93 relays require new PT connections to accommodate CETO upgrade 5 Hours
Continuous		  
23-Apr-26 12:30 23-Apr-26 17:30 ALTALINK Outage 87s 1052 (87s Gaetz) demo 1252 and 2352 breaker fail trips from the 87s1052 trip chain 5 Hours
Continuous		  
23-Apr-26 13:00 24-Apr-26 13:00 ATCO TE 832s RTU/SCADA (832s Blumenort) investigate 832S Blumenort SCADA configuration issues
 24 Hours
Continuous		  
23-Apr-26 14:01 24-Apr-26 16:00 ATCO Outage 789s 706C (789s Keg River) PRC trip coil testing 25.98 Hours
Continuous		  
24-Apr-26 07:00 24-Apr-26 17:00 ALTALINK, REDDEER Outage 464L (87s Gaetz - 209s Timberlands), 209s 464E (209s Timberlands) replace damaged/broken insulator for 1 structure 13 10 Hours
Continuous		  
24-Apr-26 07:00 04-May-26 17:00 ALTALINK Outage 238s T1 (238s Shell Harmattan) maintenance 10.42 Days
Continuous		  
24-Apr-26 07:00 25-Apr-26 17:00 ALTALINK Outage 113L (20s Ghost - 33s Spray), 20s 113 (20s Ghost), 33s 113 (33s Spray) urgent outage to replace structure 113L154 1.42 Days
Continuous		  
24-Apr-26 07:30 24-Apr-26 16:30 ALTALINK RB 778L (87s Gaetz - 217s North Red Deer) working within close proximity on 464L 9 Hours
Continuous		  
24-Apr-26 07:30 25-Apr-26 16:30 ALTALINK RB 3L (245s Seebe - 3AL tap), 3AL (43s Jumping Pound Junction - 3L tap), 3L (272s Springbank - 3AL tap), 3L (42s Sarcee - 272s Springbank) 3L recloser block required for work on 113L154 1.38 Days
Continuous		  
24-Apr-26 08:00 11-May-26 16:00 Syncrude Outage C1 (Aurora), 31 (Aurora), 32 (Aurora), 33 (Aurora), 31B (Aurora), 32A (Aurora), 32B (Aurora) zone 12 6 year maintenance 17.33 Days
Continuous		  
24-Apr-26 08:00 24-Apr-26 17:00 ALTALINK TE AltaLink Telecom Equipment firmware upgrade on MPLS node A, firewall upgrade 9 Hours
Continuous		  

Prepared On:   2026-04-17   15:23:17

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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