Alberta Electric System Operator
System Co-ordination Plan
2026-06-25 to 2026-07-03
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 17,646 Hours
Continuous		  
20-Mar-25 08:00 30-Jun-26 17:00 ALTALINK Outage 256s C1 (256s Harmattan) forced outage 11,217 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		  
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 4,137 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		  
03-Feb-26 09:00 09-Jul-26 17:00 ATCO TE 972s RTU/SCADA (972s Tinchebray) config changes needed throughout the CETO project 3,751 Hours
Continuous		  
09-Feb-26 09:00 09-Jul-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) block all 50BF protection until cutovers and associated commissioning are complete 3,607 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 26-Jun-26 16:00 ALTALINK Outage 535s C1 (535s Joffre) breaker maintenance 2,570.25 Hours
Continuous		  
28-Mar-26 12:00 26-Jun-26 17:00 ATCO TE 833s RTU/SCADA (833s Mariana) updating RTU/station controller configuration during SCADA upgrade project 1,661 Hours
Continuous		  
25-Apr-26 08:00 01-Jul-26 16:00 ENMAX Outage 1.82L (SS-1 - SS-5), 5B138-1.82 (SS-5), 1MD138-1.82 (SS-1) 1 sub Transmission line cut over 1,520 Hours
Continuous		  
25-Apr-26 08:00 01-Jul-26 16:00 ENMAX Outage 1.84L (SS-1 - SS-5), 5B138-1.84 (SS-5), 1MD138-1.84 (SS-1) 1 sub Transmission line cut over 1,520 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 28-Aug-26 17:00 EPCOR TE 987s Protection & Control (987s Clover Bar) protection blocking - relay maintenance and bus differential upgrade project 2,434 Hours
Continuous		  
26-May-26 09:30 15-Jul-26 16:30 ALTALINK Outage 157s C1 (157s Lac La Biche) trip test (157s852) 1,207 Hours
Continuous		  
27-May-26 18:00 30-Jun-26 17:00 ALTALINK Outage 526s C1 (526s Buffalo Creek) forced outage 815 Hours
Daily		  
01-Jun-26 08:00 25-Jun-26 16:00 ALTALINK TE 37s Protection & Control (37s North Calder) trip test 37s76, 37s81 584 Hours
Continuous		  
01-Jun-26 09:00 16-Jul-26 17:30 ATCO TE 865s RTU/SCADA (865s Saddlehills) updating RTU/station controller configuration during SCADA upgrade project 1,088.5 Hours
Continuous		  
02-Jun-26 10:00 13-Jul-26 16:00 ATCO Outage 743s 701T (743s Sarah Lake), 743s 705 (743s Sarah Lake), 743s 605 (743s Sarah Lake), 743s 501 (743s Sarah Lake) 743S Sarah lake rebuild 990 Hours
Continuous		  
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 30-Oct-26 17:00 EPCOR TE EP 511s Protection & Control (EP 511s Victoria) 72kV breaker fail protection blocking 2,626 Hours
Continuous		  
08-Jun-26 08:00 02-Jul-26 16:00 ENMAX Outage 37.2TR (SS-37) maintenance 440 Hours
Continuous		  
08-Jun-26 08:00 26-Jun-26 10:00 ALTALINK, ATCO Outage 87s 240kV East Bus (87s Gaetz), 9L62 (87s Gaetz - 972s Tinchebray), 962L (87s Gaetz - 972s Tinchebray), 986L (87s Gaetz - 972s Tinchebray), 9L86 (87s Gaetz - 972s Tinchebray), 87s T2 (87s Gaetz), 87s 1252 (87s Gaetz), 87s 1652 (87s Gaetz), 87s 1552 (87s Gaetz), 87s 1952 (87s Gaetz), 87s 34 (87s Gaetz) completing all telecom work & protection testing with ATCO 514 Hours
Continuous		  
09-Jun-26 07:00 13-Jul-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) relay testing 826.5 Hours
Continuous		  
09-Jun-26 07:00 14-Jul-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) isolating 50BF/705 for relay testing 178.5 Hours
Continuous		  
09-Jun-26 07:00 14-Jul-26 17:30 ATCO TE 743s Protection & Control (743s Sarah Lake) isolating 50BF/605 for relay testing 178.5 Hours
Continuous		  
10-Jun-26 08:00 26-Jun-26 16:00 SUNCOR TE 29EDD-34 RTU/SCADA (29EDD-34) add duplicate power sources 80 Hours
Continuous		  
13-Jun-26 17:01 26-Jun-26 17:00 ATCO, ALTALINK Outage 9L62 (87s Gaetz - 972s Tinchebray) work on parallel line 9L86 272 Hours
Continuous		  
15-Jun-26 07:00 24-Jul-26 17:00 EPCOR Outage EP 805s J2403 (EP 805s Jasper) J2403 replacement LCR 946 Hours
Continuous		  
15-Jun-26 07:00 26-Jun-26 17:00 ALTALINK, EPCOR TE 1056L (89s Ellerslie - 629s Argyll Transfer Station) MPLS upgrade cutover and commissioning 274 Hours
Continuous		  
15-Jun-26 07:00 04-Sep-26 17:00 EPCOR TE 805s Protection & Control (805s Jasper) protection blocking, breaker replacement project 1,954 Hours
Continuous		  
15-Jun-26 07:00 06-Jul-26 17:00 EPCOR Outage 72JM18 (EP 805s Jasper - Meadowlark), M721 (Meadowlark), M722 (Meadowlark), T1 (Meadowlark), MAB1 (Meadowlark) Meadowlark: TX1 Zone, LCR Civil Work 274 Hours
Continuous		  
15-Jun-26 08:00 26-Jun-26 16:00 ALTALINK TE 89s Protection & Control (89s Ellerslie) MPLS TPR re-arrangements project: relay testing and cutover 272 Hours
Continuous		  
15-Jun-26 08:00 25-Jun-26 09:00 ALTALINK, EPCOR RB 930L (37s North Calder - Poundmaker) reclose block for Altalink working on 37s North Calder 241 Hours
Continuous		  
15-Jun-26 08:00 25-Jun-26 09:00 ALTALINK, EPCOR RB 920L (37s North Calder - 557s Castle Downs) reclose block for Altalink working on 37s North Calder 241 Hours
Continuous		  
15-Jun-26 08:00 03-Jul-26 16:00 ALTALINK TE 254s RTU/SCADA (254s Coaldale) RTU replacement 440 Hours
Daily		  
15-Jun-26 09:00 29-Jun-26 10:00 ATCO, CNRL Outage 859s 701T (859s Primrose), 859s 701 (859s Primrose), 859s 701TD (859s Primrose), 859s 704 (859s Primrose) maintenance 337 Hours
Continuous		  
16-Jun-26 09:00 26-Jun-26 17:00 ATCO, ALTALINK Outage 972s 902 (972s Tinchebray), 972s 903 (972s Tinchebray), 9L86 (87s Gaetz - 972s Tinchebray) connect new 9L86 to 972S and prepare to energize, complete protection commissioning 224 Hours
Continuous		  
16-Jun-26 09:00 26-Jun-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) commission both 21A and 21B relays for 9L86 during the line outage 224 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		  
20-Jun-26 09:00 25-Jun-26 17:00 BCH Outage 2L294 (BCH A. A. Lambert - BCH Cranbrook) maintenance 128 Hours
Continuous		 AB-BC
21-Jun-26 07:30 30-Jun-26 09:30 ALTALINK Outage 77s 29 (77s Sagitawah) protection upgrade 218 Hours
Continuous		  
22-Jun-26 07:00 25-Jun-26 17:00 EPCOR Outage 987s GT1 (987s Clover Bar), 987s CGB1 (987s Clover Bar), 987s GDS1 (987s Cloverbar) maintenance 82 Hours
Continuous		  
22-Jun-26 07:00 03-Jul-26 17:00 ALTALINK, EPCOR TE 947L (89s Ellerslie - 987s Clover Bar) protection blocking, MPLS upgrade cutover and commissioning 274 Hours
Continuous		  
22-Jun-26 07:00 03-Jul-26 17:00 ALTALINK, EPCOR TE 915L (38s East Edmonton - 987s Clover Bar) protection blocking, MPLS upgrade cutover and commissioning 274 Hours
Continuous		  
22-Jun-26 07:00 25-Jun-26 17:00 ALTALINK TE 87s RTU/SCADA (87s Gaetz) RTU/HMI change: testing and commissioning SCADA points for line 986L CETO project 82 Hours
Continuous		  
22-Jun-26 07:00 26-Jun-26 17:00 ALTALINK, EPCOR RB 1058L (657s Summerside - EP 803s Lambton) aerial 1059L jumper repair 106 Hours
Continuous		  
22-Jun-26 07:00 26-Jun-26 17:00 EPCOR TE 72NW15 (Namao - Woodcroft), 72JW19 (EP 805s Jasper - Woodcroft) JW19/NW15: protection blocking, relay maintenance and VRR project 106 Hours
Continuous		  
22-Jun-26 07:30 26-Jun-26 17:30 CMH Outage MH-10L (MHS-10 Box Springs - MHS-8 Burnside), MHS-10 MH138-1008 (MHS-10 Box Springs), MHS-10 MH138-1011 (MHS-10 Box Springs), MHS-10 MH138-1005 (MHS-10 Box Springs), MHS10 MH138-T102 (MHS-10 Box Springs), MHS-8 MH138-803 (MHS-8 Burnside) breaker maintenance 34 Hours
Continuous		  
22-Jun-26 08:00 29-Jun-26 16:00 ATCO Outage 7L48 (794s Valleyview - 7LA48 tap), 794s 703 (794s Valleyview) pole replacement 176 Hours
Continuous		  
22-Jun-26 08:00 03-Jul-26 16:00 ALTALINK IO 89s Protection & Control (89s Ellerslie) relay testing and cutover, protection blocking, MPLS upgrade cutover and commissioning 272 Hours
Continuous		  
22-Jun-26 08:00 03-Jul-26 16:00 ALTALINK IO 38s Protection & Control (38s East Edmonton) 915L (38s East Edmonton-987s Clover Bar): relay testing and cutover, protection blocking, MPLS upgrade cutover and commissioning 272 Hours
Continuous		  
22-Jun-26 08:00 26-Jun-26 16:00 ALTALINK TE 37s RTU/SCADA (37s North Calder) RTU database update 104 Hours
Continuous		  
22-Jun-26 08:00 03-Jul-26 16:00 Syncrude Outage 89-27 (Aurora), MH1 (Aurora - Aurora) SCL - power line work 272 Hours
Continuous		  
22-Jun-26 08:00 30-Jun-26 16:00 ALTALINK TE 254s Protection & Control (254s Coaldale) perform secondary injection to P&C relays to verify the SCADA metering and DNP alarms to ACC/EMS 200 Hours
Daily		  
22-Jun-26 08:00 22-Oct-26 16:00 Syncrude Outage 814 (Syncrude Mildred Lake), 815 (Syncrude Mildred Lake), 816 (Syncrude Mildred Lake) replace 72kV underground feeder cables on west mine feeder 2,768 Hours
Continuous		  
22-Jun-26 09:00 05-Jul-26 20:00 SUNCOR Outage 29EDD-34 29PT-340 (29EDD-34), 29EDD-34 29-952-132 (29EDD-34), 29EDD-34 29-952-133 (29EDD-34), 29EDD-34 29-652-10201 (29EDD-34), 29EDD-34 29-652-10202 (29EDD-34), 29EDD-34 29-652-10203 (29EDD-34), 29EDD-34 29-652-10200T (29EDD-34) 29EDD34;29PT-340 SYSTEM;PM 5y,10y; 29EDD34;29PP-102 SYSTEM;PM 5y,10y
 323 Hours
Continuous		  
22-Jun-26 09:00 28-Jun-26 17:00 ALTALINK, EPCOR Outage 1059AL (52s East Industrial - 1059L tap), 1059L (EP 803s Lambton - 1059AL tap), 1059L (38s East Edmonton - 1059AL tap), 52s T1 (52s East Industrial), EP 803s L2401 (EP 803s Lambton), EP 803s L2404 (EP 803s Lambton), 52s E2401 (52s East Industrial), S724 (Strathcona), 52s EDS1 (52s East Industrial) East Industrial -- apparatus- TX1 Doble, and aerial- jumper conductor repair and insulator washing 152 Hours
Continuous		  
22-Jun-26 09:30 27-Jun-26 17:00 ALTALINK, EPCOR Outage 921L (71s Lamoureux - 987s Clover Bar), 987s C2404 (987s Clover Bar), 987s C2406 (987s Clover Bar), 987s CDS40 (987s Cloverbar) 921L/Cloverbar: CT/CVT/SA Doble and CDS30/CDS32/CDS40 disconnect maintenance and C2404 (Min Oil) breaker maintenance and C2404/C2406 capacitor nameplate pictures and C2401 relay maintenance 127.5 Hours
Continuous		  
22-Jun-26 09:30 27-Jun-26 17:00 ALTALINK, EPCOR IO 921L (71s Lamoureux - 987s Clover Bar) 921L/Cloverbar: CT/CVT/SA Doble and CDS9/CDS14/CDS17 disconnect maintenance and C2404 (Min Oil) breaker maintenance and C2401 relay maintenance 127.5 Hours
Continuous		  
22-Jun-26 09:30 28-Jun-26 17:00 ALTALINK, EPCOR IO 1059L (38s East Edmonton - 1059AL tap), 1059L (EP 803s Lambton - 1059AL tap) apparatus- TX1 Doble, and aerial- jumper conductor repair and insulator washing 151.5 Hours
Continuous		  
22-Jun-26 10:30 25-Jun-26 17:00 ALTALINK Outage 56L (20s Ghost - 245s Seebe), 245s 56E (245s Seebe), 20s 56 (20s Ghost) ct replacement 78.5 Hours
Continuous		  
22-Jun-26 11:00 25-Jun-26 16:00 ALTALINK TE 245s Protection & Control (245s Seebe) disable bus protections to block CTs for replacement at start of outage and then disable and unblock at time of re-energization
53 Hours
Daily		  
22-Jun-26 12:00 10-Jul-26 12:00 ATCO TE 791s RTU/SCADA (791s Rainbow Lake), 791s Protection & Control (791s Rainbow Lake) 701CT testing for breaker repair 432 Hours
Continuous		  
23-Jun-26 07:15 28-Jun-26 17:45 ALTALINK Outage 739L (14s Devon - 305s Acheson), 14s 739N (14s Devon), 305s 739 (305s Acheson) line maintenance 14s 130.5 Hours
Continuous		  
23-Jun-26 08:00 05-Jul-26 16:00 Syncrude Outage UT1 (Aurora), 12 (Aurora), 13 (Aurora) 6yr PM 296 Hours
Continuous		  
24-Jun-26 07:00 29-Jun-26 17:00 ALTALINK TE 77s RTU/SCADA (77s Sagitawah) RTU database update 130 Hours
Continuous		  
24-Jun-26 08:00 25-Jun-26 16:00 ENMAX Outage 15.60L (SS-15 - SS-21), 15B69-15.60 (SS-15), 21B69-15.60 (SS-21) HV breaker maintenance 32 Hours
Continuous		  
24-Jun-26 09:00 27-Jun-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) configuration update - ahead of Gaetz lines energization 80 Hours
Continuous		  
24-Jun-26 09:30 25-Jun-26 17:30 ATCO Outage 763s 602 (763s Hanna), 6L15 (763s Hanna - 775s Sullivan Lake), 775s 601 (775s Sullivan Lake) breaker min oil HLC partial testing 32 Hours
Continuous		  
24-Jun-26 13:00 26-Jun-26 17:30 ATCO Outage 2029s ACF21 (2029s Heathfield), 2029s 1222 (2029s Heathfield) 2029s ACF21 - filter bank AC maintenance
2029s breaker 1222 - PRC-005 trip coil testing		 52.5 Hours
Continuous		  
25-Jun-26 07:00 10-Jul-26 17:00 ALTALINK, EPCOR Outage 1044L (EP 805s Jasper - 816s Petrolia), EP 805s J2404 (EP 805s Jasper), EP 805s J2408 (EP 805s Jasper), 805s C1 (805s Jasper) J2403 replacement LCR 370 Hours
Continuous		  
25-Jun-26 08:00 25-Jun-26 16:00 ENMAX TE Protection & Control (SS-2) 2 sub 86 BF-D86 protection outage - relays, lockout testing 8 Hours
Continuous		  
25-Jun-26 08:00 25-Jun-26 16:00 ALTALINK TE 510s RTU/SCADA (510s Sunnybrook) update the RTU and HMI configuration for new intrusion alarms 8 Hours
Continuous		  
25-Jun-26 09:00 25-Jun-26 17:00 ATCO Outage 7L08 (830s Carmon - 834s Wesley Creek), 830s 701T (830s Carmon), 830s 701TCS (830s Carmon) planned outage to change out double D.E arm at Str 99 outside Carmon substation 8 Hours
Continuous		  
25-Jun-26 09:00 25-Jun-26 16:00 ATCO TE 709s RTU/SCADA (709s Vegreville) PRC-006 UFLS settings update, alarm updates 7 Hours
Continuous		  
25-Jun-26 10:00 27-Jun-26 17:00 ATCO TE 972s Protection & Control (972s Tinchebray) adjust the SPS1613 logic in both 9L93/9L16 relays to account for the two new transmission lines out of Tinchebray 55 Hours
Continuous		  
26-Jun-26 07:00 26-Jun-26 12:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 5 Hours
Continuous		  
26-Jun-26 08:00 27-Jun-26 16:00 ALTALINK TE 895s RTU/SCADA (895s Suffield) split the existing SCADA VLAN from 1 to 1 and 2 32 Hours
Continuous		  
26-Jun-26 09:00 26-Jun-26 17:00 ATCO RB 7L22 (790s Poplar Hill - 7L88 tap), 7L22 (811s Clairmont Lake - 7L88 tap), 7L88 (865s Saddle Hills - 7L22 tap) tap mobile sub up to 7L88 inside 865s Saddle Hills 8 Hours
Continuous		  
26-Jun-26 12:00 26-Jun-26 17:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 5 Hours
Continuous		  
27-Jun-26 06:30 27-Jun-26 12:30 ALTALINK Outage 77s 752 (77s Sagitawah) trip test 77s752 6 Hours
Continuous		  
27-Jun-26 07:00 27-Jun-26 17:00 EPCOR TE RTU/SCADA (Kennedale) Kennedale substation firewall replacement 10 Hours
Continuous		  
27-Jun-26 09:00 29-Jun-26 15:00 ATCO RB 7L90 (813s Little Smoky - 7LA90 tap), 7L90 (741s ATC Fox Creek - 7LA90 tap) change str 58 on 7L90 due to deficient crossarm. 54 Hours
Continuous		  
27-Jun-26 12:31 27-Jun-26 18:30 ALTALINK Outage 77s 652 (77s Sagitawah) trip test 77s652 5.98 Hours
Continuous		  
28-Jun-26 06:00 28-Jun-26 13:00 ALTALINK Outage 77s 40 (77s Sagitawah) trip test 77s40 7 Hours
Continuous		  
28-Jun-26 06:30 28-Jun-26 12:30 ATCO, ALTALINK RB 9L938 (77s Sagitawah - 809s Louise Creek) reclosing blocked for AltaLink work 6 Hours
Continuous		  
28-Jun-26 11:00 28-Jun-26 18:00 ALTALINK Outage 77s 57 (77s Sagitawah) trip test 77s57 7 Hours
Continuous		  
28-Jun-26 11:30 28-Jun-26 17:30 ATCO, ALTALINK RB 9L939 (77s Sagitawah - 809s Louise Creek) reclosing blocked for AltaLink 6 Hours
Continuous		  
29-Jun-26 07:00 10-Jul-26 17:00 ALTALINK, EPCOR TE 921L (71s Lamoureux - 987s Clover Bar) protection blocking for MPLS upgrade, cutover and commissioning 274 Hours
Continuous		  
29-Jun-26 07:00 29-Jun-26 09:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 2 Hours
Continuous		  
29-Jun-26 07:00 29-Jun-26 17:00 ALTALINK IO 77s 37 (77s Sagitawah) trip test 77s29 10 Hours
Continuous		  
29-Jun-26 07:00 29-Jun-26 17:00 EPCOR TE 805s RTU/SCADA (805s Jasper) RTU outage, firmware updates 10 Hours
Continuous		  
29-Jun-26 07:15 30-Jun-26 17:45 ALTALINK Outage 739L (14s Devon - 155s Blackmud), 14s 739E (14s Devon), 155s 739 (155s Blackmud) transmission line maintenance 34.5 Hours
Continuous		  
29-Jun-26 08:00 10-Jul-26 16:00 ALTALINK IO 71s Protection & Control (71s Lamoureux) EPCOR MPLS TPR re-arrangements project 272 Hours
Continuous		  
29-Jun-26 08:00 30-Jun-26 16:00 ENMAX Outage 16.63L (SS-16 - SS-36), 16B69-16.63 (SS-16) breaker maintenance 32 Hours
Continuous		  
29-Jun-26 08:00 29-Jun-26 16:00 ATCO, CONS RB 7L101 (790s Poplar Hill - 944s Lowe Lake) installing spacer to avoid the conductor swinging to the guy wire 8 Hours
Continuous		  
29-Jun-26 09:00 29-Jun-26 17:30 ATCO Outage 2075s ACF24 (2075s Newell), 2075S 933 (2075s Newell) PRC-005 trip coil testing, filter bank maintenance 8.5 Hours
Continuous		  
29-Jun-26 09:00 29-Jun-26 11:00 ATCO TE 932s RTU/SCADA (932s Pemukan), ATCO Telecom Equipment, APS# 201 7L224 Overload Mitigation Scheme upgrade
 2 Hours
Continuous		  
29-Jun-26 09:00 29-Jun-26 10:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 1 Hour
Continuous		  
29-Jun-26 09:00 30-Jun-26 18:00 ALTALINK, EPCOR RB 920L (37s North Calder - 557s Castle Downs), 920L (71s Lamoureux - 557s Castle Downs) safety requirement regarding 726L 33 Hours
Continuous		  
29-Jun-26 09:00 29-Jun-26 17:00 ALTALINK TE 287s Protection & Control (287s Hazelwood) DSP card replacement and FW update on the listed protection - B240B1 B87/240B1 URB30 8 Hours
Continuous		  
29-Jun-26 09:15 02-Jul-26 17:45 ALTALINK Outage 726L (37s North Calder - 71s Lamoureux), 37s 726E (37s North Calder) transmission line maintenance 80.5 Hours
Continuous		  
29-Jun-26 09:30 29-Jun-26 17:00 Lethbridge TE 146s Protection & Control (146s Macdonald) DSP card replacements and firmware upgrades to 667L "B" protections 7.5 Hours
Continuous		  
29-Jun-26 10:00 24-Jul-26 17:30 ATCO TE 763s RTU/SCADA (763s Hanna) 602T ITM replacement
, SCADA updates required as part of ITM replacement project		 439.5 Hours
Continuous		  
29-Jun-26 10:00 30-Jun-26 17:30 ATCO Outage 2029s ACF13 (2029s Heathfield) filter bank maintenance, trip coil testing 31.5 Hours
Continuous		  
29-Jun-26 10:00 29-Jun-26 11:30 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 1.5 Hours
Continuous		  
29-Jun-26 10:00 30-Jun-26 17:00 ALTALINK, EPCOR RB 920L (37s North Calder - 557s Castle Downs) Altalink work - 920LW at Castle Downs 31 Hours
Continuous		  
29-Jun-26 10:00 30-Jun-26 17:00 ALTALINK, EPCOR RB 920L (71s Lamoureux - 557s Castle Downs) Altalink work - 920LE at Castle DOwns 31 Hours
Continuous		  
29-Jun-26 11:30 29-Jun-26 17:00 ALTALINK TE 370s Protection & Control (370s North Lethbridge) DSP card replacements & firmware upgrades 5.5 Hours
Continuous		  
29-Jun-26 11:30 29-Jun-26 13:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 1.5 Hours
Continuous		  
29-Jun-26 12:30 29-Jun-26 15:30 ALTALINK Outage 435s 853A (435s Bassano), 435s T1 (435s Bassano) 435s853A PRC-005 trip coil checks 3 Hours
Continuous		  
29-Jun-26 13:00 29-Jun-26 14:30 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 1.5 Hours
Continuous		  
29-Jun-26 14:30 29-Jun-26 16:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s29 1.5 Hours
Continuous		  
30-Jun-26 07:30 30-Jun-26 16:30 ALTALINK RB 600L (404s Peace Butte - 523s Bullshead) 600L str 30, 102, 131, re-install keeper key top right phase - live line work 9 Hours
Continuous		  
30-Jun-26 07:30 02-Jul-26 17:30 ALTALINK TE 618s RTU/SCADA (618s Riverbend) RTU configuration update to remove alarms originating from the demod JMUX device.

58 Hours
Daily		  
30-Jun-26 08:00 30-Jun-26 18:00 ALTALINK Outage 77s 26 (77s Sagitawah) trip test 77s26 10 Hours
Continuous		  
30-Jun-26 08:00 30-Jun-26 16:00 ALTALINK TE 618s RTU/SCADA (618s Riverbend) techs to replace LAN-ES1 8 Hours
Continuous		  
30-Jun-26 08:00 30-Jun-26 18:00 ENMAX IO Protection & Control (SS-32) 32sub SSTR32-1, SSTR32-2, outage. 32 Sub Sump Pump AC power connection. back-up generator install during outage. 10 Hours
Continuous		  
30-Jun-26 08:30 30-Jun-26 17:00 ALTALINK Outage 631L (186s Dry Creek - 199s East Airdrie), 199s 631 (199s East Airdrie), 186s 631 (186s Dry Creek) breaker maintenance 8.5 Hours
Continuous		  
30-Jun-26 08:30 30-Jun-26 16:30 ALTALINK Outage 405s 17 (405s Waupisoo), 405s C1 (405s Waupisoo) 138kV breaker maintenance 8 Hours
Continuous		  
30-Jun-26 09:00 30-Jun-26 17:00 ALTALINK Outage 63s T2 (63s Red Deer), 63s 25 (63s Red Deer) PRC5 maintenance and first trip 6 Hours
Daily		  
30-Jun-26 09:00 30-Jun-26 16:00 ATCO TE ATCO Telecom Equipment Fairview T-Telecom/Codesa T-Telecom- radio digital AVIAT IRU 600 7GHZ PM 7 Hours
Continuous		  
30-Jun-26 09:00 30-Jun-26 17:30 ATCO Outage 2075s ACF23 (2075s Newell), 2075S 932 (2075s Newell) 2075s breaker 932 - PRC-005 trip coil testing
2075s ACF23
- filter bank AC maintenance		 8.5 Hours
Continuous		  
30-Jun-26 09:00 30-Jun-26 17:00 ALTALINK TE 177s RTU/SCADA (177s West Cascade) testing analogs on 105L to clean up SCADA deficiencies 8 Hours
Continuous		  
30-Jun-26 09:00 30-Jun-26 17:00 ALTALINK TE 77s Protection & Control (77s Sagitawah) trip test 77s26 8 Hours
Continuous		  
30-Jun-26 09:30 30-Jun-26 16:00 ATCO Outage 856s 505R (856s Kinosis), 856s 505 (856s Kinosis) PRC-005 trip coil testing, breaker maintenance 6.5 Hours
Continuous		  
30-Jun-26 10:00 30-Jun-26 16:00 ATCO Outage 856s 902T (856s Kinosis), 856s 505R (856s Kinosis), 856s 505 (856s Kinosis) PRC-005 sudden pressure relay trip testing 6 Hours
Continuous		  
01-Jul-26 08:00 01-Jul-26 18:00 ENMAX Outage 162.1TR (SS-162), 240kV North Bus (SS-162), 138kV North Bus (SS-162), 162B138-RB80 (SS-162), 162B138-RB86 (SS-162), 162B138-RB94 (SS-162), 162B240-RB131 (SS-162), 162B240-RB134 (SS-162), 162MD138-162.1TR (SS-162), 162MD240-162.1TR (SS-162) summer substation washing 10 Hours
Continuous		  
02-Jul-26 07:00 15-Jul-26 17:00 EPCOR Outage 72LS24 (EP 803s Lambton - Strathcona) LS24: Aerial Pole LCR (3 poles) 322 Hours
Continuous		  
02-Jul-26 07:00 02-Jul-26 18:00 ALTALINK, TRANSALTA RB 138s 2152 (138s Windy Flats), 608AL (528s Blue Trail Wind Farm - 608L tap), 608L (418s Ardenville - 608L tap), 608L (138s Windy Flats - 608L tap) str 34, replace damper left phase 11 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 17:00 ALTALINK TE AltaLink Telecom Equipment firmware upgrade on MPLS nodes A and B, firewall upgrade 9 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 09:59 ATCO Outage 826s 701 (826s Marguerite Lake), 826s 701A (826s Marguerite Lake) breaker maintenance 1.98 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 10:00 ENMAX Outage 2.82L (SS-2 - SS-5), 5B138-2.82 (SS-5) 1 sub Transmission line cut over. Commissioning. 2 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 17:00 ATCO Outage 839s 701T (839s Daishowa), 839s 701 (839s Daishowa) replace station service secondary conductors at 839s Daishowa
PRC-005 - spr testing - transformer 701T @ 839s
PRC-005 - trip coil testing - breaker 701 @ 839s
9 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 18:00 ALTALINK, EPCOR RB 920L (37s North Calder - 557s Castle Downs), 920L (71s Lamoureux - 557s Castle Downs) safety requirement regarding 726L 10 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 16:00 ALTALINK TE 254s RTU/SCADA (254s Coaldale) SCADA outage to commission new alarm points associated with T1 TC 8 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 12:00 ENMAX Outage 16.60L (SS-16 - SS-34) relay settings changes to 16.60L at 34 sub 4 Hours
Continuous		  
02-Jul-26 08:00 03-Jul-26 17:30 ATCO TE 865s Protection & Control (865s Saddlehills) block 701T transformer A and B protection in order to test new trip circuits to to breaker 501 33.5 Hours
Continuous		  
02-Jul-26 08:00 02-Jul-26 16:00 ENMAX TE Protection & Control (SS-5) 5 sub BMR 84 protection outage - 1 sub transmission line cut over 8 Hours
Daily		  
02-Jul-26 08:00 02-Jul-26 16:00 ENMAX TE Protection & Control (SS-5) 5 sub BMR 81 protection outage - 1 sub transmission line cut over 8 Hours
Daily		  
02-Jul-26 08:30 02-Jul-26 16:30 ALTALINK, Lethbridge Outage 254s 172W (254s Coaldale), 172L (181s Chinook - 370s North Lethbridge), 370s 172E (370s North Lethbridge) 254s172W minor maint 8 Hours
Continuous		  
02-Jul-26 08:30 02-Jul-26 17:00 ALTALINK Outage 63s 427 (63s Red Deer) PRC5 breaker maintenance & first trip 8.5 Hours
Continuous		  
02-Jul-26 09:00 03-Jul-26 17:30 ATCO Outage 2075s ACF22 (2075s Newell), 2075S 931 (2075s Newell) filter bank maintenenace 32.5 Hours
Continuous		  
02-Jul-26 09:00 02-Jul-26 17:00 ALTALINK Outage 19s 156 (19s Wabamun), 156L (19s Wabamun - 156BL tap) 138kV breaker maintenance 8 Hours
Continuous		  
02-Jul-26 09:00 02-Jul-26 10:00 ATCO TE ATCO Telecom Equipment, 739s RTU/SCADA (739s Edith Lake) Edith Lake_S-Telecom- OS upgrade 1 Hour
Continuous		  
02-Jul-26 09:00 02-Jul-26 17:00 ALTALINK TE 29s Protection & Control (29s Cascade) cutover of 54L protection alarms 8 Hours
Continuous		  
02-Jul-26 09:00 02-Jul-26 17:00 ALTALINK, EPCOR RB 920L (71s Lamoureux - 557s Castle Downs) Altalink work - 920LE at Castle Downs 8 Hours
Continuous		  
02-Jul-26 09:00 02-Jul-26 17:00 ALTALINK, EPCOR RB 920L (37s North Calder - 557s Castle Downs) Altalink work - 920LW at Castle Downs 8 Hours
Continuous		  
02-Jul-26 10:00 02-Jul-26 11:59 ATCO Outage 826s 704 (826s Marguerite Lake) breaker maintenance 1.98 Hours
Continuous		  
02-Jul-26 10:00 03-Jul-26 17:30 ATCO Outage 2029s ACF23 (2029s Heathfield), 2029s 1224 (2029s Heathfield) filter bank maintenance. 31.5 Hours
Continuous		  
02-Jul-26 10:00 02-Jul-26 11:30 ENMAX Outage 5B138-5BT12 (SS-5) 1 sub transmission line cut over 1.5 Hours
Continuous		  
02-Jul-26 10:00 02-Jul-26 17:00 ALTALINK, TRANSALTA Outage 876L (179s Gleichen - 253s Blackie), 253s 876 (253s Blackie), 179s 876 (179s Gleichen) 253s876 first trip and minor maintenance 7 Hours
Continuous		  
02-Jul-26 11:00 06-Jul-26 14:00 ATCO Outage 6L12 (775s Sullivan Lake - 6L25 tap), 775s 602 (775s Sullivan Lake) structure repair 99 Hours
Continuous		  
02-Jul-26 12:00 02-Jul-26 13:59 ATCO Outage 826s 707 (826s Marguerite Lake), 826s 708B (826s Marguerite Lake) breaker maintenance 1.98 Hours
Continuous		  
02-Jul-26 12:00 02-Jul-26 15:00 ENMAX Outage 5B138-5BT7 (SS-5) 1 sub transmission line cut over 3 Hours
Continuous		  
02-Jul-26 12:00 02-Jul-26 16:00 ENMAX Outage 15.62L (SS-15 - SS-16) relay settings changes to 15.62L at 16 sub 4 Hours
Continuous		  
02-Jul-26 14:00 02-Jul-26 15:59 ATCO Outage 826s 710 (826s Marguerite Lake), 826s 710A (826s Marguerite Lake) breaker maintenance 1.98 Hours
Continuous		  
03-Jul-26 08:00 03-Jul-26 16:00 ENMAX Outage 26.83L (SS-26 - SS-65), 26B138-26.83 (SS-26) shield wire replacement 8 Hours
Continuous		  
03-Jul-26 08:00 03-Jul-26 16:00 ALTALINK TE 276s RTU/SCADA (276s Union Carbide Prentiss) split the existing SCADA VLAN from 1 to 1 and 2 8 Hours
Continuous		  
03-Jul-26 09:00 03-Jul-26 10:59 ATCO Outage 826s 502R (826s Marguerite Lake) breaker maintenance 1.98 Hours
Continuous		  
03-Jul-26 09:00 03-Jul-26 10:00 ATCO TE 720s RTU/SCADA (720s Wabasca) upgrading fawcett_T SAR net 1 OS to V21, then V2 1 Hour
Continuous		  
03-Jul-26 11:00 03-Jul-26 12:59 ATCO Outage 826s 503R (826s Marguerite Lake) breaker maintenance 1.98 Hours
Continuous		  
03-Jul-26 11:00 03-Jul-26 12:00 ATCO TE ATCO Telecom Equipment upgrading flat top tower net 1 SAR OS to V21, then V22 1 Hour
Continuous		  

Prepared On:   2026-06-24   15:46:37

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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