B.C. five years past deadly 2021 heat dome — is it ready now?

Five years after the unprecedented heat dome that killed 619 people across B.C., the province has updated building codes and created emergency response systems — but experts say significant preparedness gaps remain.

From June 25 to July 1, 2021, B.C. experienced temperatures never recorded before. Pitt Meadows hit 41.4°C, Vancouver International 31.7°C, and Lytton reached an all-time Canadian record of 49.6°C. Nighttime temperatures stayed high throughout. Scientists later determined the heat dome would have been "virtually impossible without human-caused climate change."

B.C. was caught unprepared because the province had never experienced anything like it, said Andréanne Doyon, a professor at SFU's School of Resource and Environmental Management. "Most people, the first time they lived through an extreme heat event would have been 2021. So we have the 'We've never experienced this,' which means we've never talked about it."

The heat returned in 2022 and 2023, proving 2021 wasn't an anomaly. Yet municipalities and the province lacked trained personnel to manage extreme temperatures — most expertise was focused on stormwater management. Many B.C. buildings were also built without air conditioning or passive cooling design, and the building code didn't require temperature limits indoors.

After 2021, the province updated the B.C. Building Code to require all new residential buildings to maintain at least one living space below 26°C, either through passive design or cooling equipment. The B.C. government developed the B.C. Heat Alert and Response System and the Extreme Heat Preparedness Guide. At the municipal level, Vancouver and New Westminster have led regional efforts — Vancouver conducted its Indoor HEAT Study to understand how hot homes actually get and how heat affects residents.

Still, Doyon cautioned that expertise gaps persist. Many officials remain unprepared for the extreme heat events climate change has made routine.