Thunder Bay Hydro Coporation

Serving the City of Thunder Bay with electricity.

Outage Reasons

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At Thunder Bay Hydro, we understand that your electricity service is very important at all times. When we are working in your area, we will provide general notices to warn you of expected power outages.

Unplanned Outages

Unplanned interruptions are usually a direct result of storm damage, vehicle accidents, animals, or other unexpected events such as digging that hit an underground power line. Learn about Call Before You Dig.

For a description of current unplanned outages, you can call 343-1002 or visit our Outage Map.

  • When an outage occurs, we work first to identify and possibly solve the problem remotely. 
  • If we know the outage calls for direct intervention, we get crews to the site and ensure that proper safety procedures are in place. 
  • Then we will update our outage line with the information that we have gathered. 

This takes time.  Please expect at least a 30 minute time lag.

Social Media

When an unplanned outage is going to last for hours or affects a large area for a prolonged time, it will be classified as a MAJOR outage.  We monitor and update our social media channels (Twitter and Facebook) during MAJOR outages only

The best way to let us know about damaged equipment during any outage is to call our Control Room directly or during a regional storm event, to use our outage form

What causes power outages?

What is an 'auto-reclose'?

Auto-reclose incidents are one of the main reasons for short periods of power loss.

When an object such as a tree, bird, animal, vehicle or person comes in contact with overhead wires in such a way that grounding occurs, a fuse will open up and cut power to allow for the object to clear the line. The fuse will then close and power is restored. 

In cases where the line is still interfered with, the fuse will open again, power supply is stopped and a Thunder Bay Hydro crew is sent to the area. 

Unfortunately, whether the outage is a second or several minutes, customers who do not have battery backup on appliances or equipment are frustrated by the need to reset clocks and timers. Because electricity can seriously injure or even kill, this safety mechanism is vital for all electrical systems.


Trees are often the cause of downed power lines. You should not plant trees that will grow tall directly under power lines. Learn about our tree trimming program.

Is there anything I can do to Avoid Unexpected Power Outages?

Maintenance Work

Periodically, scheduled interruptions are required to perform maintenance on our system or to your meter. These infrequent interruptions are intended to be of short duration. If work that may require an outage is planned for your neighbourhood, you will be notified.

Planned Outages

For Notices regarding work in your area see current Ads and Notices

If you are without power for some time and hydro crews are not working in your area, you may want to call and ask.

For service outside the city of Thunder Bay, please visit the Hydro One website.