Summary of new bylaw provisions

Backfilling of downward-sloping driveways

From now on, owners of residential buildings with fewer than five housing units may backfill their downward-sloping driveways and, under certain conditions, create new, compliant outdoor parking spaces.

Underground parking

In new constructions, access to underground parking will have to be within the building itself, except for two-family (h2) and multiplex (h3) buildings.

Driveways

All new driveways will have to be designed to prevent rainwater from the street from flowing onto private property. This involves adding a mound or a slope slanted towards the street.

Basement housing

Basement dwellings will continue to be authorized in two-family and multiplex buildings. For new buildings, the entrance to the basement dwelling will have to be above the average sidewalk level. In existing buildings, access below this level will be allowed if protective measures (watertight doors, special installations) are put in place.

Limitation of basement activities

Basement activities are limited for the following uses where the clientele is more vulnerable:

• Residential and long-term care centres (CHSLDs)
• Child and youth protection centres
• Rehabilitation centres
• Schools
• Daycare centres

Other public initiatives in Saint-Laurent

These new measures are the latest addition to the many initiatives that have been in place for over 20 years, such as retention basins, bio-retention zones, sponge parks, the planting of thousands of trees and drainage landscaping on streets.

Why amend the bylaw?

• Episodes of torrential rainfalls are on the rise due to climate change (refer to the Montréal map of its “cuvettes”—topographical depressions likely to create accumulations of water and making buildings more vulnerable to the risks of flooding).
• Saint-Laurent is facing an increasing number of claims related to flooding caused by heavy rainfalls on its territory.
• These new measures stem from a number of Ville de Montréal plans based on the Montréal 2030 vision:
  • Action plan on resilience to flooding during heavy rainfalls (Service de l’eau – May 2024)
  • The third orientation of the 2025-2034 Montréal water strategy: “Reduce the impacts of rainfall on the community and the environment”
  • Urban planning and mobility plan (PUM) unveiled on June 11
• The third objective of Saint-Laurent’s 2021-2030 Climate emergency plan, namely to increase resilience against climate hazards.

Benefits of the new bylaw amendments

• Make buildings more resilient to heavy rainfalls.
• Given the current housing crisis, maintain the existing supply of basement housing and allow the creation of new basement dwellings, while better protecting them from flooding.
• Provide more options for homeowners who would like to backfill their down-sloping driveways, while retaining sufficient parking for many of them.