May 4, 2018

Hydro Ottawa Limited Major Event: May 4, 2018

Prior to Major Event


1. Did the distributor have any prior warning that the Major Event would occur?

Weather forecasts indicated that active weather was probable for the evening of May 4th. Wind gusts exceeding 90kmph were forecast. System Operations personnel reviewed weather radar from several sources late in the afternoon, and at that time the weather system appeared to be tracking south of the Ottawa area.

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? If so, please give a brief description of arrangements.

Hydro Ottawa had a full complement of on-shift personnel, and a full on-call roster of field technicians and management personnel. All Operations groups were notified early in the day of the approaching 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? If so, through what channels?

Hydro Ottawa had no prior warning that the weather would be severe or damaging and therefore did not issue any public notification.

4. Did the distributor train its staff on the response plans for a Major Event? If so, please give a brief description of the training process.

Hydro Ottawa has an established Electrical Emergency Response Plan and Organization. Formal training is completed annually according to Market Rules, and a weekly preparation meeting is held to refresh on-call management personnel.

5. Did the distributor have third party mutual assistance agreements in place prior to the Major Event? If so, who were the third parties (i.e., other distributors, private contractors)?

Hydro Ottawa is a member of the Hydro One Mutual Assistance Agreement with Ontario Local Distribution Companies (LDC's) and a member of the North Atlantic Mutual Aid Group (US based). Hydro Ottawa also has standing service level agreements with forestry contractors, civil contractors and lines contractors for planned and unplanned work.

During the Major Event


1. Please explain why this event was considered by the distributor to be a Major Event.

This event was considered to be a Major Event Day based on the IEEE Standard 1366 method. The SAIDI value of May 4, 2018 exceeded the daily SAIDI threshold, as determined by IEEE Standard 1366, based on the daily SAIDI values for the past five years.

2. Was the IEEE Standard 1366 used to identify the scope of the Major Event? If not, why not?  

Yes, the IEEE Standard 1366 was used to identify the scope of the Major Event.

3. Please identify the Cause of Interruption for the Major Event as per the table in section       

The primary cause of interruption for the Major Event was high winds.

4. Were there any declarations by government authorities, regulators or the grid operator of an emergency state of operation in relation to the Major Event?        

No, but Hydro Ottawa did activate our Electrical Emergency Response Plan at 9:50 p.m. on May 4, 2018 due to the expected duration of outages.

5. When did the Major Event begin (date and time)?       

The first weather related outages were recorded at 7:24 p.m. Multiple circuits were affected by momentary and sustained outages over the next several hours.

6. What percentage of on-call distributor staff was available at the start of the Major Event and utilized during the Major Event?   

All on-call staff were available at the start of the Major Event, and 100% of on-call staff, appropriate for the work required, were utilized during the Major Event.

7. Did the distributor issue any estimated times of restoration (ETR) to the public during the Major Event? If so, through what channels?          

Yes, Hydro Ottawa issued estimated times of restoration (ETR) through the outage map on our website ( and through our Twitter and Facebook accounts.

8. If the distributor did issue ETRs, at what date and time did the distributor issue its first ETR to the public?   

ETR's for the initial outages were issued by our Outage Management System beginning at 7:53 p.m. May 4, 2018. Communication of individual outage status was abandoned after multiple circuits opened between 8:00 p.m. and 10:00 p.m. Beginning at 1:00 a.m. on May 5, 2018 storm updates were issued on the Hydro Ottawa website until all customers were finally restored. 

9. Did the distributor issue any updated ETRs to the public? If so, how many and at what dates and times were they issued?           

Hydro Ottawa used the outage map on our website ( and Twitter to provide ETR updates. Our outage map is refreshed every five minutes with the most up-to-date information, including revised ETRs and new outages.

10. Did the distributor inform customers about the options for contacting the distributor to receive more details about outage/restoration efforts? If so, please describe how this was achieved.         

Yes, we informed customers through our social media accounts. We referred them to our outage map, which is available through our website and our free mobile app. They also could receive details through our interactive voice response (IVR) power outage line, where they could hear a recording with a high level summary of  the current outages and/or request to speak to a live agent for more details if necessary.

11. Did the distributor issue press releases, hold press conferences or send information to customers through social media notifications? If so, how many times did the distributor issue press releases, hold press conferences or send information to customers through social media notifications? What was the general content of this information?    

One news release was issued on Saturday to inform media and customers about our restoration efforts. Our shareholder, the City of Ottawa, was also informed with a memo.

12. What percentage of customer calls were dealt with by the distributor’s IVR system (if available) versus a live representative?

82.5% of callers opted for the IVR and 17.5% of customers opted for a live agent.

13. Did the distributor provide information about the Major Event on its website? If so, how many times during the Major Event was the website updated?

Yes, the outage map on our website included information on power outages and it was updated every five minutes.

14.  Was there any point in time when the website was inaccessible? If so, what percentage of the total outage time was the website inaccessible?


15. How many customers were interrupted during the Major Event? What percentage of the distributor’s total customer base did the interrupted customers represent?        

60, 811 customers were interrupted during the Major Event, representing 26% of Hydro Ottawa's total customer base.

16.  How many hours did it take to restore 90% of the customers who were interrupted?   

It took approximately 12 hours from the activation of our Electrical Emergency Response Plan to restore 90% of affected customers.

17. Was any distributed generation used to supply load during the Major Event? 

Not directly, but all available distributed generation (DG) did remain paralleled to the Hydro Ottawa distribution system.

18. Were there any outages associated with Loss of Supply during the Major Event? If so, please report on the duration and frequency of Loss of Supply outages.    

No outages during the Major Event were associated with Loss of Supply.

19. In responding to the Major Event, did the distributor utilize assistance through a third party mutual assistance agreement?     

No, not according to any formal Mutual Assistance Agreement. We did, however, use third-party contractors for forestry and lines work. Hydro Ottawa personnel were requested to assist Hydro One in the Ottawa area for the day on Monday May 7, 2018.

20. Did the distributor run out of any needed equipment or materials during the Major Event? If so, please describe the shortages. 

We did not run out of any needed equipment or materials during the event. Material was well in stock, even for our contractors assisting our restoration efforts.

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)?  

A debrief of the event was held with all stakeholders. There will be continued focus on on-call and emergency response preparation.

2. What lessons did the distributor learn in responding to the Major Event that will be useful in responding to the next Major Event?       

In order to enhance power outage restoration efforts going forward, ongoing training with the technology used to track and communicate information will be a focus. With regards to field operations for this event, limiting the overnight restoration crews to 16 Power Line Maintainers (PLM's) worked to our advantage as it allowed the majority of our PLM resources to work in the daylight hours. This resulted in a more productive and efficient effort with reduced risks, allowing 33 overhead staff members to be available during peak operating day light hours. Opening work centres throughout our service territory during the day, and dispatching crews from these remote sites, as opposed to one central location, also contributed to the success of restoration efforts. The use of two overhead contractor crews, and the use of two contractor forestry crews, contributed in the efficiency of our power restoration efforts. An administrative assistant will need to be involved at the on-set of storm restoration to log in start/end times/names of staff and locations. This will better identify who is in and qualification levels.

3. Did the distributor survey its customers after the Major Event to determine the customers' opinions of how effective the distributor was in responding to the Major Event? If so, please describe the results.      


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