Prior To Major Event
1. Did the distributor have any prior warning that the Major Event would occur?
Yes. Winds were forecasted the day prior, and in response, Hydro Ottawa executed its Major Incident Preparedness Process.
2. If the distributor did have prior warning, did the distributor arrange to have extra employees on duty or on standby prior to the Major Event beginning? Brief description of arrangements, or explain why extra employees were not arranged.
Yes. Hydro Ottawa had a full complement of on-shift personnel, and a full on-call roster of field technicians and management personnel on-site ready to respond prior to the forecasted weather.
3. If the distributor did have prior warning, did the distributor issue any media announcements to the public warning of possible outages resulting from the pending Major event?
Yes. Hydro Ottawa notified customers by posting weather advisory alerts on our outage map and website (as banners) and via social media. Messaging focused on being prepared for potential outages due to high winds and possible flash freezing. We also posted reminders on how to report an outage on social media.
4. Did the distributor train its staff on the response plans for a Major Event?
Yes.
Prior To Major Event
1. Please identify the main contributing Cause of the Major Event as per the table in section 2.1.4.2.5 of the Electricity Reporting and Record Keeping Requirements.
- Loss of Supply
- Lightning
- Adverse Weather - Wind
- Adverse Weather - Snow
- Adverse Weather - Freezing Rain/Ice Storm
- Adverse Environment - Fire
- Adverse Environment - Flooding
- Others
1.1. Please provide a brief description of the event (i.e. what happened?).
On February 28th, 2024, there were multiple outages in Hydro Ottawa's system impacting 21,911 customers due to extreme wind conditions. The majority of them occurred in the afternoon and into the night as high winds hit Hydro Ottawa’s service territory. There were two large outages impacting 18,437 customers :
- At 9:21 pm the extreme wind event caused a major interruption by tripping the breaker A9M3 at South March TS station and interrupting 10,409 customers fed from distribution stations Beaverbrook MS, Janet King DS, Richmond North DS and Munster DS.
- At 10:27 pm the Hydro One A8M 115kV transmission supply tripped resulting in a loss of supply to Hydro Ottawa substations Uplands MS and Merivale MS which led to 8,028 Hydro Ottawa customer outages.
2. Was the IEEE Standard 1366 used to identify the scope of the Major Event? If not, why not?
Yes. Hydro Ottawa used the IEEE Standard 1366.
3. When did the Major Event begin (date and time)?
February 28, 2024, at 2:52 PM
4. Did the distributor issue any information about this Major Event, such as estimated times of restoration, to the public during the Major Event? If yes, please provide a brief description of the information. If no, please explain.
Yes. Estimated Time of Restauration (ETRs) were provided on the HOL website Outage Map, sent via SMS/text message or email alert to impacted customers, and published on social media.
5. How many customers were interrupted during the Major Event? What percentage of the distributor’s total customer base did the interrupted customers represent?
21,911 customers were interrupted during the Major Event, representing 6% of Hydro Ottawa’s total customer base.
6. How many hours did it take to restore 90% of the customers who were interrupted?
There were smaller outages in the afternoon interrupting 3,443 customers (16% of total customers impacted by the weather event). Starting at 9:21 pm, there were two large interruptions impacting 18,437 customers (85% of total customers impacted by the weather event). It took 12 hours and 18 minutes since the event started to restore 90% of the customers impacted by the weather event; however, it took five hours and 39 minutes since the time the large interruptions occurred to restore 90% of the customers interrupted.
7. Were there any outages associated with Loss of Supply during the Major Event? If yes, please report on the duration and frequency of Loss of Supply outages.
Yes. There was one Loss of Supply outage during the Major Event which started at 10:27 pm. The outage impacted 8,028 customers for four hours and 33 minutes and was restored on February 29th at 3:00 am.
8. In responding to the Major Event, did the distributor utilize assistance through a third party mutual assistance agreement with other utilities? If yes, please provide the name of the utilities who provided the assistance?
No.
9. Did the distributor run out of any needed equipment or materials during the Major Event? If so, please describe the shortages.
No.
After the Major Event
1. What steps, if any, are being taken to be prepared for or mitigate such Major Events in the future (i.e., staff training, process improvements, system upgrades)?
- No further action is required at this time.
- Additional staff training
- Process improvements
- System upgrades
- Others
Additional Comments:
There is an ongoing focus on on-call and emergency response preparations with the goal of continuous improvement.