Downtown Calgary power outage offers reminders for B.C.

Image of burnt BC Hydro electrical equipment
Image shows burnt BC Hydro equipment that resulted from a 2008 fire that broke out in a manhole in downtown Vancouver.

Fire in underground vault similar to Vancouver incident in July 2008

A four-day power outage caused havoc in downtown Calgary earlier this month, after an underground fire severely damaged electrical cable serving a section of Calgary's downtown core.

The damage was extensive; ENMAX (the electrical utility that serves Calgary) had to replace 127 individual cable splices and install 3.5 kilometres of replacement electrical cable underground.

And they couldn't start work until the fire was completely out and the work area had cooled. The result was a lengthy outage for 5,000 customers in 112 buildings in a 20-block radius. 10,000 employees from 2,100 businesses in the affected area spent the time working in alternate locations.

Learn more about the Calgary outage on ENMAX's blog about the incident

Calgary's outage is certainly unusual, but not unheard of. In fact, BC Hydro customers in downtown Vancouver experienced something similar in July 2008.

Outage in downtown Vancouver six years ago also caused by a fire

On July 14, 2008 an underground circuit failed in a manhole in the 500-block of Richards Street in downtown Vancouver. A fire broke out in the manhole, which caused additional circuits to fail, leaving approximately 2,000 customers without power.

Just like in Calgary, restoration efforts and repairs needed to wait until the all-clear from the fire department before crews could safely begin work.

And like Calgary, the repairs that were needed were extensive. Crews needed to remove damaged cables, repair cable ducts, and install and splice almost four kilometres of new electrical cable. Power was restored to the first customers within a few hours, and service to about 90 per cent of affected customers was restored within 48 hours.

The downtown Vancouver outage was a good lesson that outages can happen any time, despite the best planning and industry-leading system components.

The key to mitigating outages such as the ones in Calgary and Vancouver is ongoing system improvements to increase reliability and redundancy. As every electrical utility knows, you can't eliminate power outages, but you can work to ensure that they affect as few customers as possible.

Making ongoing system improvements to help meet growing power needs in Vancouver

The demand for electricity in downtown Vancouver and across the city continues to grow. As more demand is placed on the electrical system, we're working to reinforce and upgrade components to ensure that it can reliably provide power, even as demands increase.

Over the past several years, we've made a number of significant investments into infrastructure that helps to increase reliability:

  • In 2009, we installed a third transformer in the underground Cathedral Square Substation. The substation serves about one-third of BC Hydro's downtown Vancouver customers, and adding an additional transformer creates redundancy and backup in the event of a problem.
  • In spring 2014, we completed the Vancouver City Central Transmission Project, the most significant investment to central Vancouver's electrical system in almost 30 years. A new substation in Mount Pleasant and a new underground transmission cable increases the reliability of electricity throughout Vancouver, and helps meet the demand for power in areas that are growing, such as south False Creek and Mount Pleasant.
  • We're improving electrical infrastructure in downtown Vancouver by removing "H-frame" distribution poles and taking the distribution system underground. The existing H-frame distribution system, designed to provide service to low-rise buildings, has been operating for over 50 years and is expected to reach the limits of its capacity within a decade.

Although outages such as the ones in downtown Calgary and Vancouver highlight the need for power in major urban areas, it's not just Vancouver's electrical system that requires upgrades.

In fact, since B.C.'s electricity needs are forecasted to grow 20 to 40 per cent in the next 20 years, and many of our existing assets are aging, there's a lot of investment needed to ensure reliability across the entire province.

Learn more about some of the projects underway throughout B.C.