Clearing, asphalting, and warming

Districts transformed in this manner then experience a rise in temperature and eventually turn into hot spots. “Even if we don’t build any more, the situation will deteriorate,” because of climate changes that amplify and expand these hot spots, cautions Yves Beaudoin, director of the Geography Department of the University of Quebec at Montreal (UQAM).

Elsewhere, at the rate the vegetation is thinning, cities lose their capacity to drain rainwater, a worrisome development considering the higher incidents of heavy rainfall and the inability of municipal sewer systems to handle the flow of water, notes Mr. Garand.

These problems could be overcome with simple greening solutions, indicates Yvan Vergriete, project director at the University of Montreal’s Plant Biology Research Institute and the Botanical Gardens. In Mr. Vergriete’s ‘tool box’ are the planting of trees and vegetation, fencing and sound barriers made of plants, installation of green roofs, recovery of permeable soil and the conservation of wet lands.

To illustrate the possible means of intevention, Mr. Vergriete used the example of the Laval municipal garage, on Cunard Street, in Chomedey. A map of the area included in the CRE Laval study shows that the temperature can rise to 42 degrees Celsius during a heat wave, in this Eden of Asphalt that houses the Laval Environment Department.

Without offering any estimates of the costs that changes would engender, Mr. Vergriete is of the opinion that the aesthetics, the prevailing temperatures and the drainage of rainwater could all be improved with simple greening measures.(Photos: Martin Alarie)