Alberta Electric System Operator
System Co-ordination Plan
2026-03-26 to 2026-04-03
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 30-Jun-26 14:29 ALTALINK Outage 157s C1 (157s Lac La Biche) forced outage 676.03 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		  
25-Jul-25 17:01 17-Apr-26 17:00 EPCOR Outage T2 (EP Riverview) bushing test failure (found during OE110184) 266 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		  
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		  
08-Jan-26 15:00 27-Mar-26 17:00 ALTALINK Outage 42s C2 (42s Sarcee) forced outage 78.04 Days
Daily		  
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		  
12-Jan-26 07:00 03-Apr-26 17:00 EPCOR TE 987s Protection & Control (987s Clover Bar) protection blocking, relay maintenance 81.38 Days
Continuous		  
17-Jan-26 11:00 27-Mar-26 17:00 BHE Canada Outage 120s C2 (120s Picture Butte) forced outage 69.21 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		  
06-Feb-26 07:00 30-Mar-26 17:30 ALTALINK RB 793L (87s Gaetz - 535s Joffre) crews will be setting structures on 986L/962L STR’s 41-56 & 24-41 and will require a Reclosure Block on
793L		 52.4 Days
Daily		  
08-Feb-26 07:00 06-Apr-26 18:00 ALTALINK Outage 799L (235s Entwistle - 443s South Mayerthorpe), 235s 799N (235s Entwistle) 799L rebuild between Str 721B-758 (Section B) 57.42 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		  
17-Feb-26 12:00 09-Apr-26 13:31 ATCO TE 882s RTU/SCADA (882s Triangle) updating RTU/station controller configuration during SCADA upgrade project 51.02 Days
Continuous		  
06-Mar-26 17:00 13-Nov-26 17:00 EPCOR Outage T1 (Woodcroft) woodcroft: TX1 LCR civil 252 Days
Continuous		  
09-Mar-26 07:00 27-Mar-26 17:00 EPCOR TE 816s Protection & Control (816s Petrolia) relay maintenance 18.42 Days
Continuous		  
10-Mar-26 09:00 14-Apr-26 17:00 ATCO Outage 972s 240kV Bus 900BS2 (972s Tinchebray), 972s 903 (972s Tinchebray) install breakers 905/906, 905CT/906CT, switches 905A/906B
 35.33 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 31-Mar-26 16:00 ALTALINK Outage 535s C1 (535s Joffre) breaker maintenance 20.09 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		  
14-Mar-26 07:00 29-Mar-26 17:00 EPCOR Outage 330p 500kV Bus 1 (330p Genesee), 330P 12TC1 (330p Genesee), 330p 1207 (330p Genesee), 330p 1204 (330p Genesee), 330p 1201 (330p Genesee), 330p 1210 (330p Genesee), 330p 1214 (330p Genesee), 330p 12TC1D (330p Genesee), 330p 805 (330p Genesee) POW project installation 15.42 Days
Continuous		  
15-Mar-26 07:00 01-Apr-26 17:00 EPCOR Outage 330p 1211 (330p Genesee), 330p 1210 (330p Genesee) POW project installation 17.42 Days
Continuous		  
15-Mar-26 07:00 01-Apr-26 17:00 EPCOR Outage 330P GT6 (330p Genesee) maintenance and POW project installation 17.42 Days
Continuous		  
16-Mar-26 07:00 01-Apr-26 17:00 EPCOR Outage 987s GT1 (987s Clover Bar), 987s CGB1 (987s Clover Bar) maintenance 16.42 Days
Continuous		  
16-Mar-26 07:30 16-Apr-26 15:30 CMH TE MHS-2 RTU/SCADA (MHS-2 North Industrial) replacement of existing Axiom Scout RTAC with SEL 3350 RTAC. 31.33 Days
Continuous		  
16-Mar-26 09:00 31-Mar-26 17:00 ALTALINK Outage 773L (127s Bruderheim - 308s Albchem Beaverhill Creek), 308s 773E (308s Albchem Beaverhill Creek), 127s 773W (127s Bruderheim) CT replacement associated with 308s773E. 15.33 Days
Continuous		  
16-Mar-26 10:00 26-Mar-26 16:00 ALTALINK, Lethbridge Outage 618s 824 (618s Riverbend), 824L (593s Lakeview - 618s Riverbend), 593s 824L (593s Lakeview), 593s 1 (593s Lakeview), 593s 3 (593s Lakeview) replace 593s1-disconnect switch and 593sPTL1-CVT. 10.25 Days
Continuous		  
16-Mar-26 13:00 30-Mar-26 17:00 ATCO TE 882s Protection & Control (882s Triangle) Block 701T protection to test trip/close of breaker 503 and to test inter-relay signals to new 5L482 relay 14.17 Days
Continuous		  
16-Mar-26 15:00 26-Mar-26 12:00 ALTALINK Outage 717L (17s Benalto - 262s Rocky Mountain House), 17s 717W (17s Benalto), 262s 717E (262s Rocky Mountain House) 717L component replacement 9.88 Days
Continuous		  
17-Mar-26 09:00 26-Mar-26 18:00 ALTALINK Outage 394s T2 (394s Empress) 394sVR2 replacement 9.38 Days
Continuous		  
19-Mar-26 08:00 28-Mar-26 16:00 ALTALINK Outage 931L (28s West Brooks - 132s Ware Junction), 132s 51 (132s Ware Junction), 132s 55 (132s Ware Junction), 28s 5 (28s West Brooks), 28s 8 (28s West Brooks), 132s 931 (132s Ware Junction), 28s 931N (28s West Brooks) urgent replacement of 28s 931L A - protection 9.33 Days
Continuous		  
22-Mar-26 07:00 02-Apr-26 17:00 EPCOR Outage 72JW19 (EP 805s Jasper - Woodcroft), T1 (Woodcroft), W721 (Woodcroft), W722 (Woodcroft), EP 805s J724 (EP 805s Jasper), WAB1 (Woodcroft), EP 805s JDS28 (EP 805s Jasper) Woodcroft - TX1 LCR civil (pile installs) 11.42 Days
Continuous		  
22-Mar-26 13:00 31-Mar-26 00:00 BHE Canada Outage 120s C1 (120s Picture Butte) forced outage 8.46 Days
Continuous		  
23-Mar-26 07:00 27-Mar-26 17:00 EPCOR Outage 805s T3 (805s Jasper), EP 805s J2404 (EP 805s Jasper), EP 805s J2405 (EP 805s Jasper), EP 805s JAB3 (EP 805s Jasper) Jasper T3 relay maintenance and scaffold removal 4.42 Days
Continuous		  
23-Mar-26 07:00 28-Mar-26 16:00 ALTALINK TE 28s RTU/SCADA (28s West Brooks) add new ACC alarms 5.38 Days
Continuous		  
23-Mar-26 07:00 27-Mar-26 17:00 EPCOR Outage 72RV6 (EP 511s Victoria - Rossdale), RV722 (Rossdale), EP 511s VDS9 (EP 511s Victoria) Rossdale RV722 breaker upgrade project 4.42 Days
Continuous		  
23-Mar-26 07:00 27-Mar-26 17:00 EPCOR Outage EP 511s Victoria T1 (EP 511s Victoria) Victoria T1 oil level repairs 4.42 Days
Continuous		  
23-Mar-26 07:00 27-Mar-26 17:00 EPCOR Outage T2 (Rossdale) Rossdale T2 - oil level repairs w/vendor 4.42 Days
Continuous		  
23-Mar-26 07:00 26-Mar-26 17:00 ALTALINK TE 87s RTU/SCADA (87s Gaetz) SCADA change for CETO 3.42 Days
Daily		  
23-Mar-26 07:15 26-Mar-26 17:45 ALTALINK Outage 633L (56s Boyle - 405s Waupisoo), 405s 633 (405s Waupisoo), 56s 633 (56s Boyle) component replacement on 633L15 3.44 Days
Continuous		  
23-Mar-26 08:00 31-Mar-26 16:00 ATCO Outage 7L48 (794s Valleyview - 7LA48 tap), 794s 703 (794s Valleyview) pole and cross arm replacement from T&T 8.33 Days
Continuous		  
23-Mar-26 08:00 26-Mar-26 16:00 ALTALINK Outage 514L (513s Lundbreck - 514BL tap), 513s T1 (513s Lundbreck), 513s 1 (513s Lundbreck) line maintenance 3.33 Days
Continuous		  
23-Mar-26 08:00 26-Mar-26 17:00 ALTALINK IO 633L (56s Boyle - 405s Waupisoo), 405s 633 (405s Waupisoo), 56s 633 (56s Boyle) component replacement on str 15 3.38 Days
Continuous		  
23-Mar-26 08:00 27-Mar-26 18:00 ENMAX Outage 162.1TR (SS-162) investigate tap changer oil leak and maintenance work 4.42 Days
Continuous		  
23-Mar-26 08:00 26-Mar-26 16:00 ALTALINK TE 489s RTU/SCADA (489s Petro Canada Brazeau River) upgrade firewall and LAN switch 3.33 Days
Continuous		  
23-Mar-26 08:00 02-Apr-26 16:00 ATCO, ALTALINK Outage 199L (347s AML Fox Creek - 741s ATC Fox Creek), 347s 199W (347s AML Fox Creek), 741s 702 (741s ATC Fox Creek) breaker replacement 10.33 Days
Continuous		  
23-Mar-26 08:00 26-Mar-26 16:00 ENMAX TE Protection & Control (SS-162) 162.1TR 86-T1A, 86-T1B lockout relay outage -relay protection test - 162RLY138/240 - 86 lockouts 3.33 Days
Continuous		  
23-Mar-26 08:00 27-Mar-26 16:00 ENMAX TE Protection & Control (SS-162) 162 sub 86-Z43A, 86-Z43B lockout relay, 87-Z43A, 87-Z43B differential protection outage - relay protection test - 162RLY138/240 - 86 lockouts 86-Z43-A, 86-Z43-B 4.33 Days
Daily		  
23-Mar-26 08:00 26-Mar-26 16:00 ALTALINK TE 254s RTU/SCADA (254s Coaldale), AltaLink Telecom Equipment firewall replacement and LAN switch replacement and MPLS node upgrade 7705A/B 3.33 Days
Continuous		  
23-Mar-26 08:00 29-Mar-26 17:00 ATCO, USPCE RB 7L15 (841s Long Lake - 856s Kinosis) complete 7L15 pole changes, live line work 6.38 Days
Daily		  
23-Mar-26 09:00 27-Mar-26 17:00 ALTALINK Outage 834L (320p Keephills - 384s Keystone), 320p 834X (320p Keephills), 384s 834 (384s Keystone) breaker CT replacement

4.33 Days
Continuous		  
23-Mar-26 10:00 29-Mar-26 17:00 ATCO RB 7L08 (830s Carmon - 834s Wesley Creek) maintenance program, 32 pole changes, 21 crossarm changes, other structure deficiencies 6.29 Days
Continuous		  
23-Mar-26 11:00 26-Mar-26 16:00 ALTALINK TE 237s Protection & Control (237s Foothills) 237s 2026 DSP Card replacements , relay maintenance 3.21 Days
Continuous		  
23-Mar-26 12:00 26-Mar-26 16:00 ATCO TE 898s Protection & Control (898s Heart Lake) PRC-005 relay testing, relay software vulnerability upgrade 3.17 Days
Continuous		  
23-Mar-26 12:00 26-Mar-26 16:00 ALTALINK Outage 430s 452 (430s Ursus) replace 430s452 breaker CTs 3.17 Days
Continuous		  
23-Mar-26 12:00 27-Mar-26 12:00 ATCO RB 7L121 (917s Horse River - 7LA121 tap) changing structure 99, 100, 101 due to L-G violations 4 Days
Continuous		  
23-Mar-26 12:00 26-Mar-26 17:00 ATCO Outage 813s 706 (813s Little Smoky) emergency 706CT east replacement 3.21 Days
Continuous		  
23-Mar-26 12:00 26-Mar-26 17:00 ATCO TE 813s Protection & Control (813s Little Smoky) replacing 706CT East due to extreme risk 3.21 Days
Continuous		  
23-Mar-26 13:00 26-Mar-26 09:00 ATCO Outage 2033s 704C (2033s Mowat) PRC trip coil testing BKR 704 and protection testing 2.83 Days
Continuous		  
23-Mar-26 13:00 28-Mar-26 16:30 ALTALINK Outage 65s T3 (65s High River), 65s 812W (65s High River), 65s 46 (65s High River) 65sT3 oil leak repair, doble,TC maintenance 5.15 Days
Continuous		  
23-Mar-26 13:00 26-Mar-26 16:00 ALTALINK TE 72s RTU/SCADA (72s Leismer) update alarm points/data during meter module replacements
3.13 Days
Continuous		  
23-Mar-26 14:00 27-Mar-26 14:00 ATCO Outage 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 and 7L89/7L91-230 4 Days
Continuous		  
23-Mar-26 14:00 26-Mar-26 16:00 ALTALINK Outage 310p 1852 (310p Sundance) breaker maintenance 3.08 Days
Continuous		  
24-Mar-26 08:00 27-Mar-26 14:00 ATCO RB 7L91 (715s Leming Lake - 826s Marguerite Lake) pole replacement on 7L89 poles on double circuit structures 7L89/7L91-225 and 7L89/7L91-230 3.25 Days
Daily		  
24-Mar-26 08:00 26-Mar-26 16:00 ALTALINK TE 250p RTU/SCADA (250P Bighorn Plant) RTU database update 2.33 Days
Continuous		  
24-Mar-26 08:00 29-Mar-26 17:00 ALTALINK Outage 747L (99s North St. Albert - 711L tap), 99s 747X (99s North St. Albert) replace/relocate structures 62 to 69 5.38 Days
Continuous		  
24-Mar-26 08:00 02-Apr-26 15:00 CMH TE MHS-7 Protection & Control (MHS-7 Brier Park) PRC-005 testing - remove TPR-138-T71-B from service to complete element, functional 9.29 Days
Continuous		  
25-Mar-26 09:00 26-Mar-26 16:00 ATCO TE 734s Protection & Control (734s Sturgeon) updating relay settings on 701T and 702T 31 Hours
Continuous		  
25-Mar-26 10:00 26-Mar-26 16:00 ALTALINK TE 216s Protection & Control (216s Knightsbridge) standard relay maintenance 30 Hours
Continuous		  
26-Mar-26 07:00 26-Mar-26 17:00 EPCOR TE 330p RTU/SCADA (330p Genesee) substation firewall replacement – full communications outage 10 Hours
Continuous		  
26-Mar-26 08:00 26-Mar-26 17:00 ATCO Outage 7L46 (813s Little Smoky - 845s Big Mountain), 813s 705 (813s Little Smoky), 813s 706 (813s Little Smoky), 845S 7L46D2 (845s Big Mountain) emergency 706CT east replacement 9 Hours
Continuous		  
26-Mar-26 08:00 26-Mar-26 16:00 ALTALINK TE AltaLink Telecom Equipment repair 9071R radio 8 Hours
Continuous		  
26-Mar-26 08:00 26-Mar-26 16:00 ENMAX TE Protection & Control (SS-65) 65 sub 86BF D83 lockout relay protection outage - relays, lockout testing 65RLY138-D83 8 Hours
Continuous		  
26-Mar-26 08:00 26-Mar-26 17:00 ALTALINK Outage 348s T2 (348s Marlboro), 348s 252 (348s Marlboro) customer maintenance on T2 NGR 9 Hours
Continuous		  
26-Mar-26 08:30 26-Mar-26 14:00 ALTALINK TE 263s Protection & Control (263s Strachan) on site settings change to remove ER excess trigger 718L A21/L7 SEL311C 5.5 Hours
Continuous		  
26-Mar-26 09:00 26-Mar-26 13:00 ATCO TE ATCO Telecom Equipment Poplar Hill telecom -
replace the temporary power supply for the Aprisa XE radio with the new one		 4 Hours
Continuous		  
26-Mar-26 09:00 26-Mar-26 16:30 ATCO TE 795s RTU/SCADA (795s Zama) SCADA updates for EPSS alarm and control 7.5 Hours
Continuous		  
26-Mar-26 09:00 26-Mar-26 16:00 ALTALINK TE APS# 129 Goose Lake 103s 613L Overload Mitigation Scheme troubleshoot COMM channel is down from the RAS139 B77/85/CRR relay on port 3 TMBA channel 7 Hours
Continuous		  
26-Mar-26 09:30 26-Mar-26 16:00 ALTALINK Outage 320p 752 (320p Keephills) breaker maintenance 6.5 Hours
Continuous		  
26-Mar-26 09:30 26-Mar-26 16:00 ALTALINK Outage 478s C1 (478s Tucuman) 478s552 breaker maintenance 6.5 Hours
Continuous		  
26-Mar-26 10:00 26-Mar-26 16:00 ALTALINK Outage 63s T1 (63s Red Deer), 63s 24 (63s Red Deer) PRC5 maintenance and first trip 6 Hours
Continuous		  
26-Mar-26 10:00 26-Mar-26 14:00 ALTALINK, TRANSALTA Outage 250p T2 (250p Bighorn Plant) maintenance 4 Hours
Continuous		  
26-Mar-26 10:00 26-Mar-26 16:00 ATCO Outage 856s 708C (856s Kinosis) PRC-005 - aux trip relay testing on 708C protection, trip coil testing breaker 708 6 Hours
Continuous		  
26-Mar-26 12:00 26-Mar-26 14:00 ALTALINK TE 256s Protection & Control (256s Harmattan) restore settings back to permanent settings for 717L project 2 Hours
Continuous		  
26-Mar-26 12:00 26-Mar-26 17:30 ALTALINK TE 378s Protection & Control (378s Shell Caroline) restore permanent relay settings at end of 717L line project 5.5 Hours
Continuous		  
26-Mar-26 12:00 26-Mar-26 17:30 ALTALINK TE 575s Protection & Control (575s Sundre) restore permanent P&C settings for 717L project 5.5 Hours
Continuous		  
27-Mar-26 07:00 27-Mar-26 17:00 EPCOR Outage 72CK12 (987s Clover Bar - Kennedale), 987s CK725 (987s Clover Bar) Cloverbar: CK725 (SF6) Breaker Maintenance 10 Hours
Continuous		  
27-Mar-26 07:00 27-Mar-26 19:00 ENMAX Outage 2.84L (SS-2 - SS-8) install water mains over 2.84 line 12 Hours
Continuous		  
27-Mar-26 07:00 01-Apr-26 16:00 ALTALINK TE 347s RTU/SCADA (347s Fox Creek) add new ACC alarms for s199W breaker 5.38 Days
Continuous		  
27-Mar-26 08:00 27-Mar-26 12:00 ATCO TE ATCO Telecom Equipment replacing the non redundant firewall located at SOC2 4 Hours
Continuous		  
27-Mar-26 08:00 27-Mar-26 16:00 ENMAX TE Protection & Control (SS-65) 65 sub 86BF D84 lockout relay protection outage - relays, lockout testing 65RLY138-D84 8 Hours
Continuous		  
28-Mar-26 07:00 28-Mar-26 17:00 EPCOR TE 657s RTU/SCADA (657s Summerside) RTU outage, . substation firewall replacement – Full communications outage 10 Hours
Continuous		  
28-Mar-26 08:00 28-Mar-26 16:00 ENMAX TE Protection & Control (SS-65) 65 sub 86BF D81 lockout relay protection outage - relays, lockout testing 65RLY138-D81 8 Hours
Continuous		  
28-Mar-26 08:00 29-Mar-26 16:00 ENMAX TE Protection & Control (SS-36) 36 sub autoswitching protection outage - install isolations for 36 sub C30 relay 1.33 Days
Daily		  
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		  
28-Mar-26 12:30 28-Mar-26 14:30 ALTALINK, BCH TE 5L94 (BCH Cranbrook - 520s Bennett) BPA annual RAS signal testing 2 Hours
Continuous		 AB-BC
28-Mar-26 12:30 28-Mar-26 14:30 ALTALINK TE 520s Protection & Control (520s Bennett) CBK 5L94 / 1201L PYPN, 5L94 / 1201L SYPN PN/TC. BPA Annual RAS Testing: BPA to CBK 5L94 Trip Testing (Signal check only no tripping): 2 Hours
Continuous		  
29-Mar-26 08:00 29-Mar-26 18:00 ENMAX Outage 24.81L (SS-24 - SS-31), 31.84L (SS-31 - SS-32), 31B138-24.81 (SS-31), 31B138-31.84 (SS-31), 24B138-24.81 (SS-24), 32B138-31.84 (SS-32), 31.3TR (SS-31), 31.2TR (SS-31), SW83 (SS-31), 31MD138-31.2TR (SS-31), 31MD138-31.3TR (SS-31) spring substation washing, switch sub- center blade not seated down in jaw-it is flat, reversing switch check 10 Hours
Continuous		  
30-Mar-26 07:00 02-Apr-26 17:00 EPCOR Outage 987s T3 (987s Clover Bar), 987s C2407 (987s Clover Bar) breaker maintenance and TX3 relay maintenance 3.42 Days
Continuous		  
30-Mar-26 07:00 31-Mar-26 17:00 EPCOR Outage 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 1.42 Days
Continuous		  
30-Mar-26 07:00 03-Apr-26 17:00 EPCOR Outage RR723 (Rossdale) Rossdale RR723 breaker fail upgrade project 4.42 Days
Continuous		  
30-Mar-26 07:00 31-Mar-26 17:00 EPCOR TE 72PM25 (Poundmaker - Meadowlark) PM25 protection blocking, SOM module replacement 1.42 Days
Continuous		  
30-Mar-26 07:00 02-Apr-26 17:00 ALTALINK TE 87s RTU/SCADA (87s Gaetz) SCADA change for CETO project 3.42 Days
Continuous		  
30-Mar-26 07:00 01-Apr-26 17:00 EPCOR TE EP 803s RTU/SCADA (EP 803s Lambton) RTU/SCADA maintenance 2.42 Days
Continuous		  
30-Mar-26 07:30 01-Apr-26 17:30 ALTALINK RB 615L (104s Watson Creek - 602s Cold Creek) component replacement structure 82-84 2.42 Days
Daily		  
30-Mar-26 08:00 01-Apr-26 17:00 ATCO Outage 7L50 (757s Battle River - 491L tap) Replace structure 7L50-235 2.38 Days
Continuous		  
30-Mar-26 08:00 30-Mar-26 11:00 ENMAX Outage 9.83L (SS-9 - SS-43), 9B138-9.83 (SS-9), 43B138-9.83 (SS-43) spring pothead washing 3 Hours
Continuous		  
30-Mar-26 08:00 30-Mar-26 16:00 ENMAX, ALTALINK RB 21.80L (42s Sarcee - SS-21) spring transmission line washing 8 Hours
Continuous		  
30-Mar-26 08:00 08-Apr-26 16:00 ALTALINK TE 87s Protection & Control (87s Gaetz) relay setting and wiring changes to A87/W138B & B87/W138B 9.33 Days
Continuous		  
30-Mar-26 08:00 08-Apr-26 16:00 ALTALINK TE 87s Protection & Control (87s Gaetz) relay setting and wiring changes to A87/W240B & B87/W240B 9.33 Days
Continuous		  
30-Mar-26 08:00 08-Apr-26 16:00 ALTALINK TE 87s Protection & Control (87s Gaetz) relay setting and wiring changes to A87/E138B & B87/E138B 9.33 Days
Continuous		  
30-Mar-26 08:00 08-Apr-26 17:00 ALTALINK Outage 914L (86s Bigstone - 87s Gaetz), 87s 240kV East Bus (87s Gaetz), 87s T2 (87s Gaetz), 87s 2352 (87s Gaetz), 87s 1252 (87s Gaetz), 87s 1652 (87s Gaetz), 87s 1952 (87s Gaetz), 87s 1352 (87s Gaetz), 87s 1552 (87s Gaetz) installing new 87s1352 & 87s1552, closing open points 'E', 'J', 'K' & 'L', creating permanent bus cut between 87s27 & 87s 240kV East bus 9.38 Days
Continuous		  
30-Mar-26 08:00 30-Mar-26 16:00 ENMAX, ALTALINK RB 21.80L (42s Sarcee - SS-21) spring transmission line washing 8 Hours
Continuous		  
30-Mar-26 08:00 30-Mar-26 12:00 ENMAX Outage 22.81L (SS-22 - SS-39), 22.2TR (SS-22), 22B138-22.81 (SS-22), 22MD138-22.2TR (SS-22), 22B138-22BT8 (SS-22) spring substation washing 4 Hours
Continuous		  
30-Mar-26 08:00 30-Mar-26 17:00 ALTALINK RB 615L (104s Watson Creek - 602s Cold Creek) component replacement structure 82-84 9 Hours
Continuous		  
30-Mar-26 08:00 01-Apr-26 17:00 ALTALINK, CHDI RB 514BL (322s Cowley Ridge Windplant - 514L tap), 514L (396s Pincher Creek - 514BL tap), 514L (513s Lundbreck - 514BL tap) component replacement 2.38 Days
Continuous		  
30-Mar-26 08:00 30-Mar-26 16:00 ALTALINK TE 520s Protection & Control (520s Bennett) CIP requirements - adding pushbutton control of RAS to enable/disable B protection - RAS-11 1201L and RAS-12 1201L at 520s Bennett 8 Hours
Continuous		  
30-Mar-26 08:00 02-Apr-26 16:00 ALTALINK Outage 37s 726E (37s North Calder) P&C upgrades (37s726E) 3.33 Days
Continuous		  
30-Mar-26 08:00 30-Mar-26 14:00 ALTALINK Outage 37s 747W (37s North Calder), 37s 726E (37s North Calder), 37s 898 (37s North Calder) 37s 138kV Bus outage for P&C upgrades to PT1 (37s8) 6 Hours
Continuous		  
30-Mar-26 08:00 30-Mar-26 16:00 ALTALINK TE 520s RTU/SCADA (520s Bennett) add supervisory status and control for 1201L RAS 8 Hours
Continuous		  
30-Mar-26 08:00 01-Apr-26 16:00 ENMAX Outage 162.3TR (SS-162) relay protection test - 162RLY138-162.3TR A GE, 162RLY138-162.3TR S SEL, reversing switch check 2.33 Days
Continuous		  
30-Mar-26 08:00 03-Apr-26 17:00 ALTALINK TE 37s RTU/SCADA (37s North Calder) RTU database updates 4.38 Days
Continuous		  
30-Mar-26 08:00 08-Apr-26 16:00 ALTALINK TE 87s Protection & Control (87s Gaetz) reconfiguration of the B DC chain fed from B8-4 9.33 Days
Continuous		  
30-Mar-26 08:00 30-Mar-26 16:00 ALTALINK TE 37s Protection & Control (37s North Calder) P&C protection upgrades 8 Hours
Continuous		  
30-Mar-26 08:00 31-Mar-26 16:00 ENMAX Outage 34.1TR (SS-34) tap changer inspection - 34.1-TC, reversing switch check, oil sampling MT, TC 1.33 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		  
30-Mar-26 09:00 09-Apr-26 17:00 Lethbridge Outage 823L (146s MacDonald - 593s Lakeview), 146s T2 (146s Macdonald), 146s 823L (146s Macdonald), 593s 823L (593s Lakeview), 146s 9 (146s Macdonald) Outage required to replace 146s13-Disconnect Switch, 146sPTL2-CVT, 146sPTB2-3phase CVT's, and 593s16-Disconnect Switch, 593sPTL2-CVT, 593sPTB1-3phase CVT's. *Protection Implications: 593s 824L Line Protections will not have backup Distance Protection (21) during outage due to 593sPTB1 being out 10.33 Days
Continuous		  
30-Mar-26 09:00 03-Apr-26 17:00 NWE, BHE Canada Outage Marias South Series Capacitor inspection and maintenance 4.33 Days
Continuous		 AB-MATL
30-Mar-26 09:00 04-Apr-26 17:00 SUNCOR TE 29EDD-34 RTU/SCADA (29EDD-34) change few setting / parameter in server RTU (SEL-3350) configuration and download again 5.33 Days
Continuous		  
30-Mar-26 11:00 30-Mar-26 16:00 ENMAX Outage 33.84L (SS-33 - SS-43), 33B138-33.84 (SS-33), 43B138-33.84 (SS-43) spring pothead washing 5 Hours
Continuous		  
30-Mar-26 12:00 02-Apr-26 16:00 ATCO TE 898s Protection & Control (898s Heart Lake) PRC-005 relay testing, relay software vulnerability upgrades
3.17 Days
Continuous		  
30-Mar-26 12:01 30-Mar-26 18:00 ENMAX Outage 13.82L (SS-13 - SS-22), 22.3TR (SS-22), 22.1TR (SS-22), 22B138-13.82 (SS-22), 22MD138-22.1TR (SS-22), 22MD138-22.3TR (SS-22), 22B138-22BT8 (SS-22) spring substation washing 5.98 Hours
Continuous		  
30-Mar-26 13:00 02-Apr-26 16:00 ALTALINK Outage 430s 652 (430s Ursus) 430s652 CT replacement 3.13 Days
Continuous		  
30-Mar-26 13:30 03-Apr-26 18:00 ALTALINK, EPCOR RB 1045L (EP 805s Jasper - 1045AL tap) Altalink - CT replacement for 320p 1352 4.19 Days
Continuous		  
30-Mar-26 14:00 03-Apr-26 17:00 ALTALINK, EPCOR Outage 1045AL (320p Keephills - 1045L tap), 1045L (EP 805s Jasper - 1045AL tap), 1045L (310p Sundance - 1045AL tap), 320p 1352 (320p Keephills) CT replacement w/ RMH CTs associated w/ 320p1352 (CT13) 4.13 Days
Continuous		  
30-Mar-26 14:00 01-Apr-26 16:00 ALTALINK Outage 42s C2 (42s Sarcee), 42s C3 (42s Sarcee) 42s C2/C3 - complete repair to 42sC2 re-energize once work is completed, replace the damaged capacitors and associated testing 2.08 Days
Continuous		  
30-Mar-26 15:00 01-Apr-26 16:00 ALTALINK Outage 71s 252 (71s Lamoureux) PRC5 Breaker Maintenance & First Trip 2.04 Days
Continuous		  
31-Mar-26 07:00 07-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) 50BF/701, 50BF/702, 50BF/703, 50BF/704 for relay testing 7.44 Days
Continuous		  
31-Mar-26 07:00 07-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay settings change for 51HV/701T 7.44 Days
Continuous		  
31-Mar-26 07:00 07-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay settings for 51MV/701T 7.44 Days
Continuous		  
31-Mar-26 07:00 31-Mar-26 17:00 EPCOR TE 805s RTU/SCADA (805s Jasper) Jasper: RTU/COMMS outage for emergency switch repair 10 Hours
Continuous		  
31-Mar-26 08:00 31-Mar-26 16:00 ENMAX RB 9.83L (SS-9 - SS-43) spring transmission line washing 8 Hours
Continuous		  
31-Mar-26 08:00 31-Mar-26 16:00 ENMAX RB 20.82L (SS-20 - SS-21) spring transmission line washing 8 Hours
Continuous		  
31-Mar-26 08:00 31-Mar-26 18:00 ENMAX Outage 32.83L (SS-32 - SS-40), 32.2TR (SS-32), 32.1TR (SS-32), 26.81L (SS-26 - SS-32), 32B138-32BT5 (SS-32), 32MD138-32.2TR (SS-32), 32MD138-32.1TR (SS-32), 26B138-26.81 (SS-26), 40B138-40.81 (SS-40), SW83 (SS-32), SW89 (SS-32) spring substation washing 10 Hours
Continuous		  
31-Mar-26 08:00 31-Mar-26 16:00 ALTALINK TE 33s RTU/SCADA (33s Spray) split the existing SCADA VLAN from 1 to 1 and 2 8 Hours
Continuous		  
31-Mar-26 08:00 03-Apr-26 16:00 ALTALINK TE 37s Protection & Control (37s North Calder) trip testing 37s726E 3.33 Days
Continuous		  
31-Mar-26 09:00 31-Mar-26 11:00 ATCO TE ATCO Telecom Equipment Heart Lake_S-telecom - upgrading Heart lake net 1 and net 11 SARs to v21, then v22.2 separate outage 2 Hours
Continuous		  
31-Mar-26 09:00 31-Mar-26 16:00 ATCO TE 823s RTU/SCADA (823s Wapiti) RTU updates 7 Hours
Continuous		  
31-Mar-26 09:00 31-Mar-26 16:00 ALTALINK Outage 428s 733N (428s Namaka), 733L (151s Strathmore - 428S Namaka), 151s 733E (151s Strathmore) 428s733N 138kV CB maintenance 7 Hours
Continuous		  
31-Mar-26 10:00 07-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) 21B/7L55 for relay testing,
21B/7L172 for relay settings change
, 21B/7L67 for relay settings change
 7.31 Days
Continuous		  
31-Mar-26 10:00 07-Apr-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) 21B/7L67 for relay settings change 7.31 Days
Continuous		  
01-Apr-26 07:00 02-Apr-26 17:00 EPCOR TE 72LS24 (EP 803s Lambton - Strathcona) protection blocking, SOM module replacement 1.42 Days
Continuous		  
01-Apr-26 08:00 01-Apr-26 18:00 Syncrude TE Syncrude ICCP Outage SCADA - Server Update Whole Syncrude Visibility Loss 10 Hours
Daily		  
01-Apr-26 08:00 01-Apr-26 16:00 ENMAX RB 31.84L (SS-31 - SS-32) spring transmission line washing 8 Hours
Continuous		  
01-Apr-26 08:00 01-Apr-26 16:00 ENMAX RB 24.82L (SS-24 - SS-65) spring transmission line washing 8 Hours
Continuous		  
01-Apr-26 08:00 01-Apr-26 16:00 ENMAX RB 24.81L (SS-24 - SS-31) spring transmission line washing 8 Hours
Continuous		  
01-Apr-26 08:00 01-Apr-26 17:00 ALTALINK Outage 233s 708X (233s Beamer), 708L (233s Beamer - 708AL tap) at STR 106, OHSW is rubbing on the bayonet, remove twisted shackle and put wheel between two-piece bayonet. 9 Hours
Continuous		  
01-Apr-26 08:00 01-Apr-26 18:00 ENMAX Outage 31.84L (SS-31 - SS-32), 32.3TR (SS-32), 32B138-32BT5 (SS-32), 32B138-31.84 (SS-32), 32MD138-32.3TR (SS-32) spring substation washing, reversing  switch check - 32.3-TC 10 Hours
Continuous		  
01-Apr-26 08:00 02-Apr-26 18:00 ALTALINK, NOVACORP, NOVAC Outage 330L1 (535s Joffre - 330s Nova Joffre), 535s 5652 (535s Joffre), 535s 5552 (535s Joffre), 330s BR-52 (330s Nova Joffre), 196s R3-BR-A (196s Nova Chemicals), 535s 96N (535s Joffre) electrical equipment maintenance, corrective work, line OPGW fiber testing and PRC-005 testing 1.42 Days
Continuous		  
01-Apr-26 08:00 01-Apr-26 17:00 ALTALINK TE 43s RTU/SCADA (43s Shell Canada Jumping Pound Jct) firmware upgrade on MPLS node A, firewall upgrade 9 Hours
Continuous		  
01-Apr-26 08:00 01-Apr-26 16:00 ALTALINK TE 43s RTU/SCADA (43s Shell Canada Jumping Pound Jct) split the existing SCADA VLAN from 1 to 1 and 2 8 Hours
Continuous		  
01-Apr-26 08:00 02-Apr-26 16:00 ENMAX Outage 16.2TR (SS-16) tap changer inspection - 16.2-TC, reversing switch check, oil sampling MT, TC 1.33 Days
Continuous		  
01-Apr-26 08:00 01-Apr-26 12:00 ENMAX Outage 15.60L (SS-15 - SS-21), 21B69-15.60 (SS-21), 15B69-15.60 (SS-15), SW65 (SS-21) HV breaker SF6 gas sample - 21B69-15.60 4 Hours
Continuous		  
01-Apr-26 09:00 01-Apr-26 11:00 ATCO TE ATCO Telecom Equipment Newell_T-Telecom- Upgrading Net 11 and Net 2 SARs at Newell AC.
Impact to the following traffic for up to 90 mins:
VPLS 507 - Newell AC PMU SCADA
TPRCP112 / 1087L A - Newell AC / Cassils (AML)
TPRCP113 / 1088L A - Newell AC / Cassils (AML)
VPLS 384 - Newell AC VOIP
 2 Hours
Continuous		  
01-Apr-26 09:00 02-Apr-26 17:00 ALTALINK IO 535s 5652 (535s Joffre), 535s 5552 (535s Joffre) Repair hot spot on 535s96N 1.33 Days
Continuous		  
01-Apr-26 10:00 01-Apr-26 16:00 ALTALINK Outage 56s 138kV Bus 2 (56s Boyle), 56s C1 (56s Boyle), 56s T2 (56s Boyle), 56s 710X (56s Boyle), 56s 652 (56s Boyle), 56s 16 (56s Boyle) Transformer Maintenance 6 Hours
Continuous		  
01-Apr-26 10:00 01-Apr-26 16:00 ALTALINK Outage 83s 507 (83s Taber) 83s507 SFMT Minor maint. First Trip 6 Hours
Continuous		  
01-Apr-26 12:00 01-Apr-26 16:00 ENMAX Outage 21.61L (SS-21 - SS-34), 21B69-21.61 (SS-21) HV Breaker SF6 Gas Sample - 21B69-21.61 4 Hours
Continuous		  
01-Apr-26 12:00 01-Apr-26 16:00 NOVAC TE 196s RTU/SCADA (196s Nova Chemicals) fiber testing and repair if required 4 Hours
Continuous		  
02-Apr-26 08:00 02-Apr-26 16:00 ENMAX RB 11.82L (SS-11 - SS-14) spring transmission line washing 8 Hours
Continuous		  
02-Apr-26 08:00 02-Apr-26 16:00 ENMAX RB 14.83L (SS-14 - SS-36) spring transmission line washing 8 Hours
Continuous		  
02-Apr-26 08:00 13-Apr-26 16:00 ENMAX Outage 33.84L (SS-33 - SS-43), 33B138-33.84 (SS-33), 43B138-33.84 (SS-43) shield wire and O-ring replacement 11.33 Days
Continuous		  
02-Apr-26 08:00 02-Apr-26 17:00 ALTALINK TE AltaLink Telecom Equipment firmware upgrade on MPLS node A, firewall upgrade 9 Hours
Continuous		  
02-Apr-26 08:00 02-Apr-26 16:00 ALTALINK TE 535s Protection & Control (535s Joffre) communication card change/end to end testing 8 Hours
Continuous		  
02-Apr-26 08:00 02-Apr-26 16:00 ENMAX Outage 162.4TR (SS-162) relays, lockout testing 162RLY138-162.4TR, tap changer reversing switch check 8 Hours
Continuous		  
02-Apr-26 08:00 02-Apr-26 16:00 ENMAX Outage 21.1C (SS-21), 21B138-21.CAP (SS-21) HV breaker maintenance 8 Hours
Continuous		  
02-Apr-26 16:01 02-Apr-26 18:30 ATCO, ALTALINK Outage 7L199 (347s AML Fox Creek - 741s ATC Fox Creek), 347s 199W (347s AML Fox Creek) operate A741s 702 to facilitate 1st energization of 347s199W 2.48 Hours
Continuous		  
03-Apr-26 08:00 03-Apr-26 16:00 ENMAX, ALTALINK Outage 36.81L (44s Bearspaw Plant - SS-36), 44s 36.81E (44s Bearspaw Plant), 36B138-36.81 (SS-36) shield wire replacement 8 Hours
Continuous		  
03-Apr-26 08:00 03-Apr-26 12:00 ENMAX Outage 15.62L (SS-15 - SS-16) spring transmission line washing 4 Hours
Continuous		  
03-Apr-26 08:00 03-Apr-26 12:00 ENMAX Outage 16.60L (SS-16 - SS-34) Spring transmission line washing 4 Hours
Continuous		  
03-Apr-26 08:00 03-Apr-26 17:00 ALTALINK TE 28s RTU/SCADA (28s West Brooks) changing out firewall 9 Hours
Continuous		  
03-Apr-26 08:00 03-Apr-26 16:00 ENMAX RB 3.84L (SS-3 - SS-13) pole hold on a new development outside 3 sub 8 Hours
Continuous		  
03-Apr-26 08:00 03-Apr-26 16:00 ALTALINK TE 28s RTU/SCADA (28s West Brooks) split the existing SCADA VLAN from 1 to 1 and 2 8 Hours
Continuous		  
03-Apr-26 09:00 03-Apr-26 16:00 ALTALINK, ENMAX IO 44s 36.81E (44s Bearspaw Plant), 36.81L (44s Bearspaw Plant - SS-36) shield wire replacement 7 Hours
Continuous		  
03-Apr-26 12:00 03-Apr-26 16:00 ENMAX Outage 15.60L (SS-15 - SS-21) Spring transmission line washing 4 Hours
Continuous		  
03-Apr-26 12:00 03-Apr-26 16:00 ENMAX Outage 21.61L (SS-21 - SS-34) Spring transmission line washing 4 Hours
Continuous		  

Prepared On:   2026-03-25   15:29:13

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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