Montreal expects more brutal heat waves, vows to improve response

Montreal's public health authority says better awareness and improved institutional responsiveness meant the death rate during the 2018 heat wave was lower than during a similar crisis in 2010, but the 66 deaths it says were directly related to the heat last year were nonetheless "avoidable."

In 2018, 66 people died due to heat

Montreal was smothered by the heat wave from June 30 to July 5 2018, with maximum temperatures reaching as high as 35.5 C — more than 40 C with the humidex. (Simon-Marc Charron/Radio-Canada)

Climate change will make heat waves in Montreal more frequent and more brutal, public health authorities and city officials say, and they want to better protect the city's most vulnerable residents.

In 2018, 66 deaths were directly related to the heat, according to a new report by Montreal's public health authority. That works out to 6.4 deaths per day, per million inhabitants. 

Better public awareness and improved institutional responsiveness meant there were far fewer deaths than the summer of 2010, when there were 9.3 deaths per day, per million inhabitants, but the 2018 deaths were nonetheless "avoidable," said public health officials.

"It is going to be difficult to have zero deaths from a heat wave, but there is room for improvement," said Dr. Mylène Drouin, the director of public health for the Montreal region, at a media event to release the report and the plan for 2019. 

'We can improve the way we're reaching out' to those most at risk from extreme heat, said Dr. Mylène Drouin, the director of public health for the Montreal region. (CBC)

Montreal was smothered by the heat wave from June 30 to July 5 2018, with maximum temperatures reaching as high as 35.5 C — more than 40 C with the humidex — and minimums remaining above 20 C. 

Schizophrenics highly vulnerable

The report found that low income and social isolation were key factors in the deaths attributable to that heat wave. Of those who died, two out of three were 65 years old or older, and nearly three in four — 72 per cent — had a chronic condition.

A disproportionate number of deaths in 2018 occurred among people suffering from schizophrenia. Those victims made up 25 per cent of the total, even though they represent just 0.6 per cent of Montreal's population.

Part of the issue is that those suffering from schizophrenia can be less sensitive to heat because of their condition and the drugs they take to manage it, said Drouin. Their medications can interfere with the body's ability to eliminate heat.

"We need to refine the types of interventions and the frequency with which we visit them," she said.

The public health authority is working with various partners to build a registry of people in need and where to find them, and it plans to have it finished by the end of June, Drouin said. 

They are using housing data, social and mapping data to show hot spots, in combination with the knowledge of various first responders and health workers with first-hand knowledge of vulnerable areas and individuals.

During 2018's heat wave, police and firefighters made 42,000 door-to-door visits, but Drouin said the intention is to make the on-the-ground efforts more targeted and more effective.

"We can improve the way we're reaching out," she said. "We want to ensure the people doing the interventions are people they trust."

Greening projects

Environment Canada says it's too early to issue a summer forecast, but meteorologist André Cantin says data so far suggests the summer of 2019 will be close to, or slightly above normal. Last summer was below normal during the month of June, but well above normal during July and August.

Children play in the water fountains at Place des Arts on July 3, 2018. (Eva Hambach/AFP/Getty Images)

Coun. Laurence Lavigne-Lalonde, the city's executive member responsible for environmental sustainability, said greening projects — such as putting up temporary walls made of plants and erecting canopies to create more shade — would provide short-term relief to people living in or near urban heat islands.

Heat islands are areas in a city where the summer heat is trapped by expanses of concrete, brick and asphalt, exacerbated by a lack of green space and shade from trees.

"As a city, we have to make sure we're reducing greenhouse gases and creating an environment that is healthier, that we're not increasing these climate hazards," Lavigne-Lalonde said. "On the other hand, we have to be able to respond when these hazards emerge."

Differing numbers

The total deaths from the 2018 heat wave differ from report to report, but this is because not all used the same methodology.

The Montreal public health authority's methodology considered all deaths over the heat wave period and used statistical criteria to identify deaths very likely related to heat, while the Quebec coroner's numbers are based upon evidence from autopsies.

"Evidently, both methodologies have their limits," Drouin said. "Not every death is going to be referred to the coroner."