A project to better manage rainwater in the Aldis-Bernard alley

Mercier–Hochelaga-Maisonneuve is planning the development of the Aldis-Bernard sponge lane. The project aims to better manage rainwater, while maintaining car access to backyards and private parking lots. The objective is to reduce the risk and extent of flooding.

The Aldis-Bernard alley is located in a low point of the district, i.e. a basin of more than 300 mm. This means that during intense rainfall, excess water from the surrounding areas naturally flows there, which represents a risk of flooding for the surrounding residences.

In addition, the current taxiway, although unpaved, absorbs very little water, because the soil

has been compacted over time by the passage of cars. With the higher level of this road compared to private land, water flows into backyards.

The creation of a sponge alley was therefore recommended with the aim of improving the situation.

The project

The work planned for 2026 will make it possible to:

• create slight slopes in the alley and drainage pits to direct rainwater
• redo the car traffic lane with a coating that will help absorb water from the ground
• create a rain garden that will retain excess water to reduce pressure on the sewers

The information and exchange meeting

On September 10, 2025, the borough's teams presented the initial development plans and the work to be carried out to the neighbourhood.

A discussion period was held to answer questions and gather feedback from participants for the finalization of the development plans.

For more information:

• Read the project presentation
• Read the Q&A document