Renovation of D'Isère Avenue and De Namur Street
In the summer of 2026, the Ville de Saint-Lambert will carry out infrastructure work on D'Isère Avenue, between De Namur Street and Lambert-Closse Park, as well as on De Namur Street, between D'Isère Avenue and De Namur Place. A retention basin will also be installed in the green space of the Terrasse d’Isère. This will promote rainwater retention at the source while contributing to the area’s biodiversity.
These works will allow for the expansion of sections of sewer lines and the installation of surface drainage infrastructure, thereby improving rainwater retention in the area and the resilience of the infrastructure.We are conscious of the inconveniences caused by such a major project and how they will disrupt your daily life. We would therefore like to help you prepare for the work.
Schedule
- Early May: Work begins at the intersection of D'isère Avenue and De Namur Street.
- Early May to mid-June: Construction of a retention basin in the green space of the D'Isère terrace.
- Mid-May to mid-June: Work continues on De Namur Street, between D’Isère Avenue and De Namur Place.
- Early June: Repair work on D'Isère Avenue, between De Namur Street and Lambert-Closse Park.
- June: Work continues on De Namur Street, between Simard Boulevard and D'Isère Avenue, then on D'Isère Avenue, between De Namur Street and D'Isère Place.
- July: Finishing work, including repairs to the driveways and landscaping damaged during construction.
- Mid-August: Completion of the project.
The construction zone will be closed to traffic as soon as demolition begins. With some exceptions, local traffic will be permitted for residents of the construction zone.
Detours
Phase 1A: De Namur Street, between D'Isère Avenue and Simard Boulevard
- One lane of traffic will remain open at all times.
- During working hours, traffic will be directed by flaggers.
- Outside of working hours, temporary stop signs will be installed to facilitate traffic flow.
Phase 1B: De Namur Street, between D'Isère Avenue and De Namur Place
- Motorists on De Namur Place will be able to access Simard Boulevard by continuing on De Namur Street and taking D'Isère Avenue.
Phase 2: D'Isère Avenue, between De Namur streets
- Motorists will be able to access Simard Boulevard by taking De Namur Street
Phase 2: D'Isère Avenue, between De Namur Street and Lambert-Closse Park
- Drivers on the D'Isère terrace can access Victoria Avenue via a temporary path set up in Lambert-Closse Park and on the property at 2001 Victoria Avenue (shaded path below).

Detailed work
D'Isère Terrace
A new open-air retention basin will be constructed in the green space of the D'Isère Terrace. Trees will be preserved or relocated.
D'Isère Avenue, between De Namur Street and Lambert-Closse Park
A linear underground retention basin will be installed beneath the street. Above the basin, a vegetated swale (landscaped drainage ditch) will be created. The addition of these new drainage features will require a reduction in the street’s width. Parking will henceforth be permitted on only one side of the street along this section.
In addition, during surface work:
- the drinking water main will be relocated;
- the combined sewer line will be replaced with a higher-capacity line.
De Namur Street, between D'Isère Avenue and De Namur Place
The work will include replacing the sewer line to increase its capacity. The street’s geometry will remain unchanged.
De Namur Street, between D'Isère Avenue and Simard Boulevard
A vegetated swale and a linear underground retention basin will replace the sidewalk on the side of 2001 Victoria Avenue. The rest of the street’s layout will remain similar to the existing one, and the asphalt will be repaved along the entire length of the section.
D'Isère Avenue, between D'Isère Place and De Namur Street
On this section, a vegetated swale and a linear underground retention basin will replace an existing sidewalk. The street layout will remain largely the same, and the roadway will be entirely repaved with asphalt.
Neighbourhood residents
The reconstruction of a street is a complex operation involving several companies, and it disrupts people’s lives. We invite you to consult the Practical information during roadwork page, which will offer practical tips to ensure your daily routine remains as unaffected as possible.
News
The information on this page will be continually updated. We invite you to check it regularly for progress reports on the work.