Alberta Electric System Operator
System Co-ordination Plan
2026-08-06 to 2026-08-14
Approved Outages

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From To Owner Type Element Scheduled Activity Date/Time Comments Interconnection
26-Jul-24 10:00 30-Jun-27 16:00 ATCO Outage 826s 504R (826s Marguerite Lake) emergency removal to replace failed 502R @834S 25,662 Hours
Continuous		  
20-Mar-25 08:00 07-Aug-26 17:00 ALTALINK Outage 256s C1 (256s Harmattan) forced outage 12,129 Hours
Continuous		  
25-Nov-25 17:46 18-Sep-26 18:00 ATCO Outage 876s 901T (876s Brintnell) forced outage oil leaking 7,127.23 Hours
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 17,528 Hours
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 5,791 Hours
Continuous		  
21-Jan-26 08:00 30-Oct-26 16:00 ENMAX Outage 5.7TR (SS-5) 25kV switchgear replacement 6,775 Hours
Continuous		  
06-Mar-26 17:00 13-Nov-26 17:00 EPCOR Outage T1 (Woodcroft) woodcroft: TX1 LCR civil 6,048 Hours
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 6,368 Hours
Continuous		  
11-Mar-26 13:45 15-Sep-26 08:59 ALTALINK Outage 535s C1 (535s Joffre) breaker maintenance 4,507.23 Hours
Continuous		  
01-May-26 17:00 25-Nov-26 17:00 EPCOR Outage T1 (Meadowlark) T1 LCR civil work 4,993 Hours
Continuous		  
19-May-26 07:00 02-Oct-26 17:00 EPCOR TE 987s Protection & Control (987s Clover Bar) protection blocking - relay maintenance and bus differential upgrade project 2,434 Hours
Continuous		  
27-May-26 18:00 18-Aug-26 17:00 ALTALINK Outage 526s C1 (526s Buffalo Creek) forced outage 1,991 Hours
Daily		  
04-Jun-26 07:01 10-Feb-27 17:00 EPCOR Outage T1 (Rossdale) rossdale: TX1 lcr civil 6,034.98 Hours
Continuous		  
07-Jun-26 17:05 01-Oct-26 00:00 ACCIONA, ENBRIDGE, ICPCL Outage 139s C1 (139s Hillridge) forced outage 2,766.92 Hours
Continuous		  
08-Jun-26 07:00 04-Dec-26 17:00 EPCOR TE EP 511s Protection & Control (EP 511s Victoria) 72kV breaker fail protection blocking 2,626 Hours
Continuous		  
15-Jun-26 07:00 18-Dec-26 17:00 EPCOR TE 805s Protection & Control (805s Jasper) protection blocking, breaker replacement project 1,954 Hours
Continuous		  
19-Jun-26 17:00 03-Dec-27 17:00 EPCOR Outage EP 511s Victoria T3 (EP 511s Victoria) emergency outage due to degraded asset condition 12,769 Hours
Continuous		  
10-Jul-26 08:00 18-Nov-26 16:00 Syncrude Outage 815 (Syncrude Mildred Lake), 816 (Syncrude Mildred Lake) replace 72 kV underground feeder cables on west mine feeder 2,696 Hours
Continuous		  
14-Jul-26 00:00 31-Aug-26 00:00 ALTALINK Outage 151s C1 (151s Strathmore) forced outage 1,152 Hours
Continuous		  
14-Jul-26 08:00 01-Oct-26 17:00 ALTALINK IO 287s 552 (287s Hazelwood) 287s552 must be open during 443L and 417L outage for the 214s AIS to work properly 1,905 Hours
Continuous		  
15-Jul-26 14:01 28-Sep-26 09:00 ALTALINK Outage 417L (55s Olds - 281s Johnson), 55s T1 (55s Olds), 55s T2 (55s Olds), 55s 417 (55S Olds), 287s 552 (287s Hazelwood), 55s 2 (55s Olds) mobile install at 55s for P_C major upgrade, repair/replace s80, s83, s84. salvage s51. 1,962.98 Hours
Continuous		  
20-Jul-26 07:00 31-Dec-26 17:00 EPCOR TE Protection & Control (Woodcroft) woodcroft: protection blocking for TX1 LCR, line protection testing, and repairs 3,947 Hours
Continuous		  
20-Jul-26 07:00 04-Sep-26 17:00 EPCOR TE 330p Protection & Control (330p Genesee) genesee: protection blocking, firmware updates 1,114 Hours
Continuous		  
20-Jul-26 14:30 07-Aug-26 17:00 ALTALINK Outage 1083L (63s Red Deer - 288s Wolf Creek), 63s 452 (63s Red Deer), 63s 552 (63s Red Deer), 288s 352 (288s Wolf Creek), 288s 152 (288s Wolf Creek), 288s 1083 (288s Wolf Creek), 63s 1083 (63s Red Deer) 63s452 breaker replacement 434.5 Hours
Continuous		  
26-Jul-26 08:00 08-Aug-26 16:00 Syncrude Outage 14 (Aurora), 213 (Aurora), 223 (Aurora), 24 (Aurora), 34 (Aurora), 260kV Bus 2 (Aurora), 72 kV Bus 2 (Aurora), T11 (Aurora), 89-216 (Aurora), 89-52 (Aurora) zone 1 6 year PM at Aurora 272 Hours
Continuous		  
27-Jul-26 07:00 04-Sep-26 17:00 EPCOR Outage EP 805s J2401 (EP 805s Jasper) Jasper: J2401 replacement LCR 946 Hours
Continuous		  
27-Jul-26 07:00 07-Aug-26 17:00 ALTALINK, EPCOR TE 1045L (EP 805s Jasper - 1045AL tap) protection blocking for MPLS cutovers and commissioning 274 Hours
Continuous		  
27-Jul-26 08:00 07-Aug-26 16:00 ALTALINK IO 310p Protection & Control (310p Sundance), 320p Protection & Control (320P Keephills) 1045L/1045AL (Sundance 310P -Keephills 320P-E805 Jasper Terminal EPCOR): relay testing and cutover, protection blocking

272 Hours
Continuous		  
27-Jul-26 10:00 31-Aug-26 17:00 ATCO Outage 827s 701T (827s Cranberry Lake) class2 major testing
 76 Hours
Continuous		  
28-Jul-26 07:00 14-Aug-26 17:00 EPCOR Outage EP 511s Victoria T3 (EP 511s Victoria), EP 511s V724 (EP 511s Victoria), EP 511s V725 (EP 511s Victoria), EP 511s VAB3 (EP 511s Victoria) TX3 extended zone for demolition 418 Hours
Continuous		  
28-Jul-26 10:00 10-Aug-26 16:00 ATCO Outage 6L11 (743s Sarah Lake - 854s Swan Dive), 743s 603 (743s Sarah Lake) 743S Sarah lake rebuild - replace breaker 603 318 Hours
Continuous		  
30-Jul-26 09:00 07-Aug-26 17:00 BCH RB 5L92 (BCH Cranbrook - BCH Selkirk) 5L92 LLP/ANR - barehand insulator replacement 200 Hours
Continuous		 AB-BC
31-Jul-26 07:30 06-Aug-26 16:30 ALTALINK Outage 378s T1 (378s Shell Caroline) customer work 153 Hours
Continuous		  
31-Jul-26 08:00 06-Aug-26 20:00 ATCO, SUNCOR TE 29PL9-2 (29EDD-1 Millennium - 848s Ruth Lake), 29EDD-1 Protection & Control (29EDD-1 Millennium) protection isolation 156 Hours
Continuous		  
01-Aug-26 08:00 31-Aug-26 20:00 SUNCOR Outage 29EDD-60 29PT-702 (29EDD-60 Inglis Island) IBP pressure low 732 Hours
Continuous		  
03-Aug-26 08:00 28-Aug-26 16:00 ENMAX Outage 2.82L (SS-2 - SS-5), 5B138-2.82 (SS-5) A phase replacement, 12 hr soak test 608 Hours
Continuous		  
03-Aug-26 08:00 04-Sep-26 16:00 ENMAX TE Protection & Control (SS-5) 5 sub zone 31 auto switching protection scheme outage, 25kV switchgear addition 776 Hours
Daily		  
03-Aug-26 08:00 14-Aug-26 15:00 CMH TE MH-60L (MHS-5 NE Crescent Heights - MHS-7 Brier Park) maintenance on the LDR-60L-B 271 Hours
Continuous		  
03-Aug-26 08:00 06-Aug-26 16:00 ALTALINK TE 163s Protection & Control (163s Amoco Empress) momentarily blocking the protection to isolate the CT contribution from T5 clip on CT 80 Hours
Daily		  
03-Aug-26 08:00 30-Oct-26 16:00 ALTALINK TE 55s RTU/SCADA (55s Olds) adding/testing new alarms & controls associated with the 55s P&C 2,120 Hours
Daily		  
03-Aug-26 23:47 06-Aug-26 17:00 ENMAX, ALTALINK Outage 47B138-771/1 (SS-47) forced outage 65.22 Hours
Continuous		  
04-Aug-26 07:00 10-Aug-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) isolating 21B/6L11 for relay testing. 154.5 Hours
Continuous		  
04-Aug-26 07:00 10-Aug-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) 50BF/603 for relay testing 154.5 Hours
Continuous		  
04-Aug-26 07:00 10-Aug-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay isolation 21A/6L11 for testing 154.5 Hours
Continuous		  
04-Aug-26 07:00 10-Aug-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) 86-50BF/600BS1. 94-50BF/600BS1 for testing 154.5 Hours
Continuous		  
04-Aug-26 07:00 08-Aug-26 17:00 EPCOR TE Protection & Control (Garneau) Garneau: protection blocking for RG1/RG7/MG16 setting updates 106 Hours
Continuous		  
04-Aug-26 07:00 06-Aug-26 17:00 EPCOR Outage 72RV6 (EP 511s Victoria - Rossdale), EP 511s V723 (EP 511s Victoria), EP 511s V724 (EP 511s Victoria), RV722 (Rossdale), EP 511s VDS9 (EP 511s Victoria) Victoria: RV6 zone, clearance to remove TX3 from site, emergency project 58 Hours
Continuous		  
04-Aug-26 07:03 05-Sep-26 17:00 ALTALINK Outage 869L (163s Amoco Empress - 204s Sandy Point), 204s T1 (204s Sandypoint), 163s 869W (163s Amoco Empress) customer maintenance work 777.95 Hours
Continuous		  
04-Aug-26 07:30 13-Aug-26 08:30 ALTALINK Outage 77s 652 (77s Sagitawah) protection upgrade 77s652 217 Hours
Continuous		  
04-Aug-26 08:00 24-Aug-26 12:00 ENMAX, ALTALINK Outage 24.83L (74s Janet - SS-24), 74s 24.83X (74s Janet) wood pole installation 416 Hours
Continuous		  
04-Aug-26 08:00 24-Aug-26 16:00 ALTALINK, ENMAX IO 74s 24.83X (74s Janet), 24.83L (74s Janet - SS-24) Enmax wood pole installation 488 Hours
Continuous		  
04-Aug-26 08:00 13-Aug-26 16:00 ALTALINK TE 62s RTU/SCADA (62s Brazeau Plant) replace RTU 224 Hours
Continuous		  
04-Aug-26 08:00 06-Aug-26 16:00 ALTALINK TE 186s RTU/SCADA (186s Dry Creek) supervisory outages to upgrade meter modules 56 Hours
Continuous		  
04-Aug-26 08:00 10-Aug-26 16:00 ATCO RB 7L48 (787s High Prairie - 7L48 tap), 7L48 (794s Valleyview - 7LA48 tap) changing rotten poles and cross arm. 152 Hours
Continuous		  
04-Aug-26 09:00 06-Aug-26 17:30 ATCO Outage 2029s 1302 (2029s Heathfield) DC high speed switch maintenance 56.5 Hours
Continuous		  
04-Aug-26 09:00 06-Aug-26 17:00 ENMAX, ALTALINK Outage 5s T2 (5s East Calgary), MD113 (SS-2) 5sT2 PRC doble, major maint 56 Hours
Continuous		  
04-Aug-26 09:00 09-Aug-26 17:30 ALTALINK RB 501CL (983s Cadomin - 501L tap), 501L (426s Coalspur - 501CL tap) urgent repairs, replace arms,insulation, and structure

128.5 Hours
Daily		  
04-Aug-26 13:00 08-Aug-26 17:00 ATCO RB 7L85 (801s Anderson - ATC 803s Bullpound), 7L85 (803s ATC Bullpound - 7LA85 tap), 7L85 (804s Wintering Hills - 7LA85 tap) installing interphase spacers 146 Hours
Continuous		  
04-Aug-26 13:00 06-Aug-26 16:30 ALTALINK Outage 453L (305s Acheson - 367s Harry Smith), 305s 453 (305s Acheson), 367s 453 (367s Harry Smith) 138kV breaker maintenance 51.5 Hours
Continuous		  
04-Aug-26 19:01 17-Aug-26 11:00 BCH Outage 5CB9 (BCH Selkirk), 5CB8 (BCH Selkirk) replace 5PT9, 5L91 remains in service 303.98 Hours
Continuous		 AB-BC
04-Aug-26 19:01 17-Aug-26 11:00 BCH RB 5L91 (BCH Ashton Creek - BCH Selkirk) 5L91 AR turned off 303.98 Hours
Continuous		 AB-BC
05-Aug-26 07:00 21-Aug-26 17:00 EPCOR Outage 72LH8 (EP 803s Lambton - EP Hardisty) aerial pole LCR (3 poles) and surge arrestor repair and HDS13 repair 394 Hours
Continuous		  
05-Aug-26 07:00 06-Aug-26 16:00 ALTALINK Outage 310p 2852 (310p Sundance) test 310p2852 CTs 33 Hours
Continuous		  
05-Aug-26 07:00 06-Aug-26 17:00 ALTALINK TE 310p Protection & Control (310p Sundance) isolate protections for CT2852 testing 34 Hours
Daily		  
05-Aug-26 08:00 10-Aug-26 15:00 ATCO RB 7L159 (770s Three Hills - 7L159 tap) pole straightening and deficiency repair 127 Hours
Continuous		  
05-Aug-26 08:00 06-Aug-26 16:00 ENMAX Outage 39.2TR (SS-39) relay protection test and reversing switch check 32 Hours
Continuous		  
05-Aug-26 13:00 05-Sep-26 13:00 ATCO TE 2085s Protection & Control (2085s Sheridan) power quality meter install at 2085s Sheridan
 744 Hours
Continuous		  
06-Aug-26 07:00 12-Aug-26 17:00 ALTALINK Outage 378s T2 (378s Shell Caroline), 378s 852 (378s Shell Caroline) customer work 154 Hours
Continuous		  
06-Aug-26 07:30 09-Aug-26 18:00 ALTALINK Outage 709L (54s Fort Saskatchewan - 172s Sherritt), 54s 709N (54s Fort Saskatchewan), 172s 709X (172s Sherritt) replace structure 59 Hours
Continuous		  
06-Aug-26 08:00 06-Aug-26 17:00 ALTALINK Outage 180s T2 (180s Cope Creek), 180s 252 (180s Cope Creek) heater change/investigation 9 Hours
Continuous		  
06-Aug-26 08:00 06-Aug-26 16:00 ALTALINK TE 310p RTU/SCADA (310p Sundance), AltaLink Telecom Equipment MPLS Node A&B&C upgrade - loss of 310p visibility for 2 hours in the timeframe indicated 8 Hours
Daily		  
06-Aug-26 08:00 06-Aug-26 12:00 ENMAX Outage 35B138-82 (SS-35) breaker trip circuit test - 35B138-82 4 Hours
Continuous		  
06-Aug-26 08:00 11-Aug-26 17:00 SUNCOR Outage 635EDD-1000 635PT-1003 (635EDD-1000) planned maintenance on 72kV bus 635PP-1003 129 Hours
Continuous		  
06-Aug-26 08:00 06-Aug-26 17:00 ATCO TE ATCO Telecom Equipment, 705s RTU/SCADA (705s Kitscoty) firmware upgrade 9 Hours
Continuous		  
06-Aug-26 08:00 06-Aug-26 17:00 ATCO TE ATCO Telecom Equipment, 716s RTU/SCADA (716s Lloydminster) firmware upgrade 9 Hours
Continuous		  
06-Aug-26 08:00 06-Aug-26 17:00 ATCO TE ATCO Telecom Equipment, 768s RTU/SCADA (768s Rowley) firmware upgrade 9 Hours
Continuous		  
06-Aug-26 09:00 06-Aug-26 16:00 ATCO TE ATCO Telecom Equipment, APS# 158 Ksituan 754S Voltage Stability Mitigation harris contestation major PM. Radio will be out of service from 10am-2pm. team at both ends of the link 7 Hours
Continuous		  
06-Aug-26 09:00 06-Aug-26 17:00 ALTALINK Outage 283s 30 (283s Violet Grove) 283s31 CT testing 8 Hours
Daily		  
06-Aug-26 09:00 07-Aug-26 17:00 ATCO Outage 7L12 (834s Wesley Creek - 7LA12 tap), 834s 710 (834s Wesley Creek), 834s 710B (834s Wesley Creek), 834s 704 (834s Wesley Creek) breaker SF6 GL312 complete testing, 710B is non-operational 32 Hours
Continuous		  
06-Aug-26 09:00 06-Aug-26 16:00 ALTALINK TE 799s RTU/SCADA (799s Coleman) tech to push RTU configuration to address and issue with 25 kV bus analogs 7 Hours
Continuous		  
06-Aug-26 09:00 06-Aug-26 12:00 ALTALINK TE 359s RTU/SCADA (359s Esso West Pembina), AltaLink Telecom Equipment MPLS upgrade node A 3 Hours
Daily		  
06-Aug-26 12:01 06-Aug-26 16:00 ENMAX Outage 35B138-83 (SS-35) breaker trip circuit test 3.98 Hours
Continuous		  
06-Aug-26 14:01 06-Aug-26 20:00 SUNCOR Outage 29EDD-1 29EDD1s252 (29EDD-1 Millennium) PRC-005 trip test, trip and reclose the breaker 5.98 Hours
Continuous		  
07-Aug-26 07:00 13-Aug-26 16:00 ALTALINK TE 77s RTU/SCADA (77s Sagitawah) RTU database update 153 Hours
Daily		  
07-Aug-26 08:00 17-Aug-26 16:00 Syncrude Outage MH1 (Aurora - Aurora), 24 (Aurora), 23 (Aurora) zone 11 6yr preventative maintenance 248 Hours
Continuous		  
07-Aug-26 08:00 08-Aug-26 16:00 ENMAX RB 33.84L (SS-33 - SS-43) pole hold 32 Hours
Continuous		  
07-Aug-26 08:30 07-Aug-26 09:30 ATCO TE ATCO Telecom Equipment upgrading relay OS 1 Hour
Continuous		  
08-Aug-26 07:00 08-Aug-26 11:30 EPCOR Outage 987s CC24 (987s Clover Bar) Cloverbar: CC24, BUS Diff Upgrade Cutovers 4.5 Hours
Continuous		  
08-Aug-26 08:00 11-Aug-26 16:00 ALTALINK TE 62s Protection & Control (62s Brazeau Plant) Protection outages to perform secondary injection to verify the SCADA metering to ACC/EMS. Redundant protection will remain in place. All protection outages will be returned by EOD everyday. 80 Hours
Daily		  
08-Aug-26 08:00 08-Aug-26 18:00 ENMAX, ALTALINK IO 832L (SS-10 - SS-12) Substation Structure Painting 10 Hours
Continuous		  
08-Aug-26 08:00 13-Aug-26 20:00 SUNCOR TE 29EDD-1 29EDD1s1852 (29EDD-1 Millennium), 29EDD-1 29EDD1S1452 (29EDD-1 Millennium) 29EDD-1 / X72B1 SOUTH BUS PRC-005 / Relay testing - 450338057
This will be done under protection isolation and ring bus breakers will be opened one at a time to keep the South 72kv bus online		 132 Hours
Continuous		  
08-Aug-26 12:00 08-Aug-26 17:00 EPCOR Outage 987s CN723 (987s Clover Bar), 72CN10 (987s Clover Bar - Namao) Cloverbar: CN723, BUS Diff Upgrade Cutovers 5 Hours
Continuous		  
09-Aug-26 07:00 09-Aug-26 11:30 EPCOR Outage 987s CC13 (987s Clover Bar) Cloverbar: CC13, BUS Diff Upgrade Cutovers 4.5 Hours
Continuous		  
09-Aug-26 07:00 13-Aug-26 17:00 ALTALINK IO 77s 38 (77s Sagitawah) Test the functionality of clearing the 138kV East Bus by simulating opening 77s38 as part of clearing the bus
77s38 WILL NOT be opening, that function will be disabled for this test		 106 Hours
Continuous		  
09-Aug-26 07:00 09-Aug-26 17:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) Protection outages for trip testing, redundant protections in place at all times 10 Hours
Daily		  
09-Aug-26 08:00 10-Aug-26 13:00 ATCO Outage 7L85 (803s ATC Bullpound - 7LA85 tap) Interphase spacer install, Deficiency repairs & insulator replacement between Badlands and Bullpound 29 Hours
Continuous		  
09-Aug-26 08:00 09-Aug-26 18:00 ENMAX, ALTALINK IO 833L (SS-2 - SS-12) Substation Structure Painting 10 Hours
Continuous		  
09-Aug-26 08:00 09-Aug-26 17:00 SUNCOR Outage 635EDD-1001 635PS-1094 (635EDD-1001) Trouble shoot 635PS-1094 disconnect status to SCADA 9 Hours
Continuous		  
09-Aug-26 12:00 09-Aug-26 17:00 EPCOR Outage 987s CK725 (987s Clover Bar), 72CK12 (987s Clover Bar - Kennedale) Cloverbar: CK725, BUS Diff Upgrade Cutovers 5 Hours
Continuous		  
10-Aug-26 06:00 11-Aug-26 08:00 ALTALINK Outage 404s T1 (404s Peace Butte), 404s 600 (404s Peace Butte) Customer request for 24 hour outage to replace power cables from low side of T1 to 404s7.
26 Hours
Continuous		  
10-Aug-26 06:30 10-Aug-26 12:29 ALTALINK Outage 77s 752 (77s Sagitawah) trip testing 77s752 5.98 Hours
Daily		  
10-Aug-26 07:00 16-Aug-26 17:00 EPCOR Outage 665s T3 (665s Dome), 665s D721 (665s Dome), 665s D2404 (665s Dome), S721 (Strathcona) Dome TX3 and disconnect maintenance 154 Hours
Continuous		  
10-Aug-26 07:00 10-Aug-26 17:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) 77s652 breaker fail trip testing 10 Hours
Daily		  
10-Aug-26 07:30 02-Oct-26 17:00 ALTALINK Outage 434s T3 (434s East Stony Plain) T3 transformer replacement 1,281.5 Hours
Continuous		  
10-Aug-26 08:00 13-Aug-26 16:00 ALTALINK TE 95s RTU/SCADA (95s Imperial Oil Edmonton), AltaLink Telecom Equipment MPLS 95S-7705B addition, and 95S-7705A upgrade 80 Hours
Continuous		  
10-Aug-26 08:00 13-Aug-26 16:00 ALTALINK TE AltaLink Telecom Equipment MPLS 9095R-7705B addition, 9095R-7705A upgrade 80 Hours
Continuous		  
10-Aug-26 08:00 11-Aug-26 16:00 ENMAX Outage 37B138-37.81 (SS-37), 37.81L (SS-37 - SS-38) HV breaker maintenance 32 Hours
Continuous		  
10-Aug-26 08:00 17-Aug-26 16:00 ENMAX Outage 37.81L (SS-37 - SS-38), 37B138-37.81 (SS-37), 38B138-37.81 (SS-38) siding work near line 176 Hours
Continuous		  
10-Aug-26 08:00 13-Aug-26 16:00 ATCO TE 969s Protection & Control (969s Lindbergh) settings changes to 50BF/701, 67-67N-32-59/5L767, SPS/969 80 Hours
Continuous		  
10-Aug-26 08:00 10-Aug-26 17:00 ALTALINK TE 267s RTU/SCADA (267s Killarney Lake) RTU database update 9 Hours
Daily		  
10-Aug-26 08:00 10-Aug-26 17:00 ALTALINK TE 267s Protection & Control (267s Killarney Lake) protection upgrade 9 Hours
Daily		  
10-Aug-26 08:00 12-Aug-26 16:00 ALTALINK TE 103s Protection & Control (103s Goose Lake) PRC maintenance 56 Hours
Daily		  
10-Aug-26 08:00 11-Aug-26 16:00 ENMAX Outage 8.1TR (SS-8) tap changer inspection 32 Hours
Continuous		  
10-Aug-26 08:00 14-Aug-26 16:00 ALTALINK TE 395s RTU/SCADA (395s North Holden) update RTU/HMI configuration 104 Hours
Daily		  
10-Aug-26 08:30 10-Aug-26 17:30 ALTALINK RB 757L (17s Benalto - 758L tap), 757L (297s Rimbey - 758L tap), 758L (534s Eckville - 757L tap) 758L21 Prep day 9 Hours
Daily		  
10-Aug-26 09:00 13-Aug-26 16:00 ATCO Outage 969s 701T (969s Lindbergh), 969s Protection & Control (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

coordinated with dates provided by Strathcona Resources, awaiting confirmation from IPL		 79 Hours
Continuous		  
10-Aug-26 09:00 28-Sep-26 10:00 ALTALINK Outage 58s T1 (58s Edson) 58s T1 transformer replacement and containment install 1,177 Hours
Continuous		  
10-Aug-26 09:00 13-Aug-26 17:30 ALTALINK Outage 701L (223s Strome - 395s North Holden), 223s 39 (223s Strome), 395s 701X (395s North Holden) 701L19 & 26, splice out all three phases at points of support on structures 19 and 26 80.5 Hours
Continuous		  
10-Aug-26 10:00 14-Aug-26 17:30 ATCO Outage 959s SVC (959s Lanfine), 959s 921 (959s Lanfine) SVC transformer maintenance

103.5 Hours
Continuous		  
10-Aug-26 10:00 20-Aug-26 17:30 ATCO TE 2029s Protection & Control (2029s Heathfield) relay firmware upgrade 247.5 Hours
Continuous		  
10-Aug-26 10:00 10-Aug-26 18:00 ATCO TE 706s Protection & Control (706s Irish Creek) settings changes to 50BF/702 RTU Alarm configuration updates. 8 Hours
Continuous		  
10-Aug-26 10:00 13-Aug-26 16:00 ALTALINK TE 245s Protection & Control (245s Seebe) Techs to temporary disable A87/138BN and B87/138BN Bus protections for approx 1hr to block at the beginning & end of the outage for 245s754W CT replacement. Protections are redundant. 11(96/25SC)/652, 754L A21/79/L7 & 754L B21/L7 will be out of service for the duration of the outage. 78 Hours
Continuous		  
10-Aug-26 10:00 13-Aug-26 16:00 ALTALINK TE 186s RTU/SCADA (186s Dry Creek) supervisory outage to upgrade meter modules 78 Hours
Continuous		  
10-Aug-26 11:00 13-Aug-26 16:30 ALTALINK Outage 71s 138kV West Bus (71s Lamoureux), 71s T1 (71s Lamoureux), 71s 152 (71s Lamoureux), 71s 552 (71s Lamoureux), 71s C1 (71s Lamoureux), 71s C2 (71s Lamoureux) transformer maintenance, switch maintenance, breaker maintenance 77.5 Hours
Continuous		  
10-Aug-26 11:00 10-Aug-26 18:00 ALTALINK Outage 77s 29 (77s Sagitawah) trip test 77s29 7 Hours
Daily		  
10-Aug-26 12:00 13-Aug-26 18:00 ALTALINK Outage 754L (245s Seebe - 742L tap), 245s 754W (245s Seebe) 245s754W CT replacement 78 Hours
Continuous		  
10-Aug-26 12:00 10-Aug-26 17:00 EPCOR Outage 987s CCP7213 (987s Clover Bar) bus diff upgrade cutovers 5 Hours
Continuous		  
10-Aug-26 12:30 13-Aug-26 17:00 ALTALINK Outage 17s 85 (17s Benalto), 17s T2 (17s Benalto) 17s85 CT replacement 76.5 Hours
Continuous		  
10-Aug-26 13:00 13-Aug-26 13:00 ATCO TE 939s Protection & Control (939s Livock) CIP update password at 939S 72 Hours
Continuous		  
10-Aug-26 13:00 10-Aug-26 14:00 ATCO Outage 951s 1205 (951s Thickwood Hills) PRC-005 trip coil testing 1 Hour
Continuous		  
10-Aug-26 14:00 18-Aug-26 17:00 ALTALINK, FORTIS Outage 275s T1 (275s Jenner), 275s 38 (275s Jenner), 275s 2152 (275s Jenner), 275s 2269 (275s Jenner), 275s 81 (275s Jenner), 275s 2036N (275s Jenner), 275s 52 (275s Jenner), 275s 52F1 (275s Jenner), 275s 52F2 (275s Jenner) replace LV bushings, TC Maintenance, copper cutouts 195 Hours
Continuous		  
10-Aug-26 14:01 10-Aug-26 15:00 ATCO Outage 951s 1206 (951s Thickwood Hills) PRC-005 trip coil testing 0.98 Hours
Continuous		  
10-Aug-26 15:01 10-Aug-26 16:00 ATCO Outage 951s 1213R (951s Thickwood HIlls) PRC-005 trip coil testing 0.98 Hours
Continuous		  
11-Aug-26 06:30 11-Aug-26 12:30 ALTALINK Outage 77s 40 (77s Sagitawah) trip test 77s40 6 Hours
Daily		  
11-Aug-26 07:00 13-Aug-26 18:00 ALTALINK Outage 310p 1852 (310p Sundance) Replace 310p1852 CT's 59 Hours
Continuous		  
11-Aug-26 07:00 12-Aug-26 17:00 ALTALINK Outage 102s 552 (102s Langdon), 102s 252 (102s Langdon), 102s T4 (102s Langdon), 102s SVC (102s Langdon) install a config change on the MACH controls from the controls system upgrade 34 Hours
Continuous		  
11-Aug-26 07:00 11-Aug-26 17:00 ALTALINK, TRANSALTA Outage 876L (179s Gleichen - 253s Blackie), 179s 876 (179s Gleichen), 253s 876 (253s Blackie) strain insulator replacement at 179s Gleichen. 10 Hours
Continuous		  
11-Aug-26 07:00 13-Aug-26 18:00 ALTALINK TE 310p Protection & Control (310p Sundance) isolate protections for CT1852 testing, restore protections daily 59 Hours
Daily		  
11-Aug-26 07:00 11-Aug-26 19:00 ATCO RB 840S 9LS1MD1 (840s McNeill Station) SaskPower is requesting a Holdoff on the S1M line due to work in close proximity for August 11, 2026 from 7:00 – 19:00 12 Hours
Continuous		  
11-Aug-26 07:15 16-Aug-26 16:45 ALTALINK Outage 790L (434s Stony Plain - 790AL tap), 434s 790 (434s Stony Plain) LOA for old 434s T3 transformer removal 129.5 Hours
Continuous		  
11-Aug-26 08:00 12-Aug-26 17:30 ALTALINK Outage 758L (534s Eckville - 757L tap), 534s T1 (534s Eckville), 534s 758 (534s Eckville), 534s 138kV Bus 1 (534s Eckville), 534s 40 (534s Eckville) 758L21 Structure Change 33.5 Hours
Continuous		  
11-Aug-26 08:00 12-Aug-26 16:00 ENMAX TE Protection & Control (SS-24) 24sub BMR 83 protection outage 32 Hours
Daily		  
11-Aug-26 08:00 11-Aug-26 16:00 ALTALINK TE AltaLink Telecom Equipment, 212s RTU/SCADA (212s Lacombe), 423L (212s N.E. Lacombe - 332s Ellis) MPLS Node A + Raw Socket Upgrade - Aug 11 (SIA Attached)
LAN Switch Replacement + Firewall Replacement - Aug 12
Loss of 423L protections for 2 hours. Loss of visibility of 212s for 2 hours.		 8 Hours
Daily		  
11-Aug-26 08:00 11-Aug-26 16:00 SUNCOR TE 29EDD-65 Protection & Control (29EDD-65) replace faceplate on F-35 8 Hours
Continuous		  
11-Aug-26 09:00 11-Aug-26 11:00 ATCO TE ATCO Telecom Equipment, 969s RTU/SCADA (969s Lindbergh), 940s RTU/SCADA (940s Beartrap), 706s RTU/SCADA (706s Irish Creek) Moose Hill_T-Telecom/Irish Creek_S-Telecom/Lindbergh_S-Telecom- upgrade SAR's 2 Hours
Continuous		  
11-Aug-26 09:00 11-Aug-26 16:00 ATCO TE ATCO Telecom Equipment, 735s RTU/SCADA (735s Swan River) radio major MDR 8502 PM at Swan River 1735 to Swan Dive Twr 7 Hours
Continuous		  
11-Aug-26 09:00 12-Aug-26 17:00 ATCO TE ATCO Telecom Equipment MPLS life cycle upgrades to SAR A, new SAR A, cards 1.3/1.4 slots
32 Hours
Continuous		  
11-Aug-26 09:00 12-Aug-26 17:00 ATCO TE ATCO Telecom Equipment Cavendish MPLS life cycle upgrades to SAR A, new SAR A, ETH cards, slot 1.1/1.2, SDI cards 1.3/1.4 slots 32 Hours
Continuous		  
11-Aug-26 09:00 14-Aug-26 17:00 ATCO Outage 834s 902T (834s Wesley Creek), 834s 503 (834s Wesley Creek) transformer class1 tap changer investigate heater fail - 503 at 834S Wesley Creek 80 Hours
Continuous		  
11-Aug-26 09:00 11-Aug-26 12:45 ATCO TE ATCO Telecom Equipment radio major PM at Slim's Creek 1655 to Meikle 3.75 Hours
Continuous		  
11-Aug-26 10:00 24-Aug-26 16:00 ATCO Outage 6L96 (735s Swan River - 743s Sarah Lake), 743s 604 (743s Sarah Lake), 735s 604 (735s Swan River) 743S sarah lake rebuild, replace breaker 604 318 Hours
Continuous		  
11-Aug-26 10:00 11-Aug-26 11:00 ATCO Outage 939s 1206 (939s Livock) PRC-005 trip coil testing 1 Hour
Continuous		  
11-Aug-26 10:00 11-Aug-26 18:00 ATCO TE 700s Protection & Control (700s Bonnyville) settings changes to 50BF/702, RTU alarm configuration updates 8 Hours
Continuous		  
11-Aug-26 11:00 11-Aug-26 14:00 ALTALINK Outage 221s C1 (221s Sunken Lake) cap bank weed spraying 3 Hours
Daily		  
11-Aug-26 11:01 11-Aug-26 12:00 ATCO Outage 939s 1207 (939s Livock) PRC-005 trip Coil testing, SOC open and close breaker (tests TC #1), isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2) 0.98 Hours
Continuous		  
11-Aug-26 12:01 11-Aug-26 13:00 ATCO Outage 939s 1214R (939s Livock), 939s 1214 (939s Livock) PRC-005 trip coil testing, SOC will open and close breaker (tests TC #1), techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2) 0.98 Hours
Continuous		  
11-Aug-26 12:31 11-Aug-26 18:00 ALTALINK Outage 77s 57 (77s Sagitawah) trip test 77s57 5.48 Hours
Daily		  
11-Aug-26 13:00 11-Aug-26 17:00 ATCO TE ATCO Telecom Equipment radio major PM at Slim's Creek 1655 to Keg 4 Hours
Continuous		  
11-Aug-26 13:01 11-Aug-26 14:00 ATCO Outage 939s 1216R (939s Livock), 939s 1216 (939s Livock) PRC-005 trip coil testing, SOC will open and close breaker (tests TC #1), techs will isolate A protection tripping this breaker, TOC will open and close breaker (tests TC #2) 0.98 Hours
Continuous		  
12-Aug-26 06:00 12-Aug-26 17:00 ATCO TE ATCO RTU/SCADA SOC2 Backup Control Centre activation 11 Hours
Continuous		  
12-Aug-26 07:00 16-Aug-26 17:00 EPCOR Outage T1 (Meadowlark), M722 (Meadowlark), M721 (Meadowlark), 72JM18 (EP 805s Jasper - Meadowlark), MAB1 (Meadowlark), EP 805s J722 (EP 805s Jasper) TX1zone, LCR civil work 106 Hours
Continuous		  
12-Aug-26 08:00 12-Aug-26 17:00 ATCO TE ATCO Telecom Equipment Lindbergh telecom new SAR A, SDI cards 1.3/1.4 slots 9 Hours
Continuous		  
12-Aug-26 08:00 12-Aug-26 16:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) protection outages for trip testing 8 Hours
Daily		  
12-Aug-26 08:00 13-Aug-26 16:00 ENMAX Outage 31.3TR (SS-31) tap changer inspection, reversing switch check, oil sampling and maintenance 32 Hours
Continuous		  
12-Aug-26 08:00 13-Aug-26 16:00 ALTALINK TE AltaLink Telecom Equipment MPLS maintenance 32 Hours
Daily		  
12-Aug-26 09:00 12-Aug-26 17:30 ATCO TE 815s Protection & Control (815s Goodfare) ground two CTs separately to remedy the issue and prevent a second mis-operation on 815S 701T protection 8.5 Hours
Continuous		  
12-Aug-26 10:00 12-Aug-26 18:00 ATCO TE 710s Protection & Control (710s Vermilion), 710s RTU/SCADA (710s Vermilion), 706s Protection & Control (706s Irish Creek) settings changes to 21B/7L117 8 Hours
Continuous		  
13-Aug-26 06:00 18-Aug-26 18:00 SUNCOR Outage 635EDD-1000 635PK-1001 (635EDD-1000), 635EDD-1000 635-752-161 (635EDD-1000), 635EDD-1000 635-752-162 (635EDD-1000), 635EDD-1000 635PS-1044 (635EDD-1000) planned maintenance of diameter 132 Hours
Continuous		  
13-Aug-26 07:00 13-Aug-26 11:30 EPCOR Outage 987s CS2 (987s Clover Bar), 987s SST2 (987s Clover Bar) bus diff upgrade cutovers 4.5 Hours
Continuous		  
13-Aug-26 07:00 13-Aug-26 17:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) breaker fail protection outage (77s652) for trip testing, no redundancy 10 Hours
Daily		  
13-Aug-26 08:00 13-Aug-26 16:00 ALTALINK TE 356s Protection & Control (356s Milo) 927L settings changes for metering updates 8 Hours
Daily		  
13-Aug-26 08:00 13-Aug-26 16:00 ALTALINK TE 356s RTU/SCADA (356s Milo) configuration updates for L4 protection metering updates 8 Hours
Daily		  
13-Aug-26 08:00 13-Aug-26 16:00 ENMAX TE Protection & Control (SS-3) 138 kV bus differential protection, lockout relay protection outage, relay protection test 8 Hours
Continuous		  
13-Aug-26 08:31 13-Aug-26 17:30 ALTALINK Outage 77s 552 (77s Sagitawah) trip test 77s552 8.98 Hours
Continuous		  
13-Aug-26 09:30 14-Aug-26 16:00 ATCO TE ATCO Telecom Equipment, 840s RTU/SCADA (840s McNeill Station) moving communication and Scada traffic onto new star link device
30.5 Hours
Continuous		  
13-Aug-26 10:00 13-Aug-26 12:59 SUNCOR Outage 29EDD-1 29EDD1s1852 (29EDD-1 Millennium) PRC-00, relay testing 2.98 Hours
Continuous		  
13-Aug-26 10:00 13-Aug-26 16:00 ATCO TE 977s Protection & Control (977s Salt Creek) troubleshoot communication to 901T ground current monitoring device 6 Hours
Continuous		  
13-Aug-26 12:00 13-Aug-26 16:00 ALTALINK TE 395s RTU/SCADA (395s North Holden), AltaLink Telecom Equipment MPLS upgrade 4 Hours
Continuous		  
13-Aug-26 13:00 13-Aug-26 17:00 SUNCOR Outage 29EDD-1 29EDD1S1452 (29EDD-1 Millennium) PRC-005, relay testing 4 Hours
Continuous		  
14-Aug-26 07:00 15-Aug-26 18:00 ALTALINK Outage 720L (347s AML Fox Creek - 397s Benbow), 347s 720X (347s AML Fox Creek), 397s 720N (397s Benbow) urgent, 720L repair existing dead-ends on structure 99 & 99A 35 Hours
Continuous		  
14-Aug-26 08:00 14-Aug-26 12:00 ENMAX Outage 162B138-RB85 (SS-162), 162B138-RB86 (SS-162), 162.3TR (SS-162) summer substation washing 4 Hours
Continuous		  
14-Aug-26 08:00 17-Aug-26 20:00 SUNCOR TE 29EDD-1 29EDD1s1052 (29EDD-1 Millennium), 29EDD-1 29EDD1s852 (29EDD-1 Millennium) 29EDD1/ X260B2 south bus PRC-005 / relay test 84 Hours
Continuous		  
14-Aug-26 09:00 14-Aug-26 11:00 ATCO TE ATCO Telecom Equipment upgrading the Dino park SAR OS to V21, then V22 2 Hours
Continuous		  
14-Aug-26 09:00 15-Aug-26 17:30 ALTALINK Outage 1034L (244s Bowmanton - 324s Cassils) urgent repair 1034L6 OPGW 32.5 Hours
Continuous		  
14-Aug-26 09:00 15-Aug-26 17:30 ATCO, ALTALINK RB 1088L (324s Cassils - 2075s Newell) 1088L proximity R/B For 1034L urgent repair 32.5 Hours
Daily		  
14-Aug-26 09:00 15-Aug-26 17:30 ATCO, ALTALINK RB 9L1088 (324s Cassils - 2075s Newell) AltaLink request: 1034L urgent repair. block reclosers on 1088L @ 2075s 32.5 Hours
Continuous		  
14-Aug-26 10:00 28-Aug-26 17:30 ATCO Outage 7L65 (709s Vegreville - 7LA65 tap), 709s 703 (709s Vegreville) 7L65 rebuild - phase 3 - protection upgrade at 709S, 708S and 710S
343.5 Hours
Continuous		  
14-Aug-26 12:00 21-Aug-26 17:30 ATCO TE 709s Protection & Control (709s Vegreville) 7L65 rebuild - phase 3

173.5 Hours
Continuous		  
14-Aug-26 12:00 14-Aug-26 18:00 ENMAX Outage 162B138-RB92 (SS-162), 162B138-RB94 (SS-162), 162.4TR (SS-162) summer substation washing 6 Hours
Continuous		  
14-Aug-26 17:00 14-Aug-26 19:00 BCH Outage 2L293 (BCH Nelway - BCH Selkirk) instrument transformer replacement project 2 Hours
Continuous		 AB-BC

Prepared On:   2026-08-05   15:11:43

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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