Preserving a Heritage Landmark in Montreal:

Restoring the Sainte-Hélène Island Pavilion

Located in the heart of Montreal’s Jean-Drapeau Park, the Sainte-Hélène Island Pavilion has stood the test of time since 1931. This iconic Art Deco building, which also serves as a support structure for the Jacques Cartier Bridge, is now undergoing a major heritage restoration project.

In a vibrant urban setting beneath one of Quebec’s most important transportation corridors, Pomerleau has been entrusted with revitalizing this unique infrastructure while preserving its historic character. The project sits at the intersection of civil engineering, heritage conservation and infrastructure modernization.

A Major Heritage Project for Montreal

The project involves the complete restoration of the pavilion and its four towers, using a phased approach that allows surrounding activities to continue uninterrupted. The objective is clear: preserve a historic building while ensuring its durability for decades to come at a site that is both highly frequented and strategically important to the city. Work began on the West Towers in 2025, and restoration of the East Towers is expected to be completed by the end of 2026.

Restoring a Historic Building Without Altering Its Character

Every intervention is designed to respect the original architecture while improving the building’s performance. Teams are restoring the façades, replacing more than 300 windows and doors with replicas faithful to the originals, and reproducing nearly 180 historic terracotta mosaics.

Iconic elements such as the bronze bust of Jacques Cartier and commemorative plaques are also being carefully restored. At the same time, significant structural work is being carried out on load-bearing walls, slabs and tower staircases.

Working in a Complex, Active Environment

The construction site is located directly beneath the Jacques Cartier Bridge, an infrastructure used daily by thousands of motorists. Teams must navigate major challenges, including vibrations, noise, confined spaces and planned traffic restrictions required to maintain vehicle flow.

The scaffolding systems are particularly complex, designed to withstand heavy loads and wind conditions while ensuring worker safety. In addition, strict containment measures are required due to the presence of lead in existing materials, demanding rigorous health, safety and environmental protocols.In this context, detailed planning and close coordination among trades are essential to keeping the project on schedule.

Multidisciplinary Expertise Supporting Heritage Preservation

This project brings together a wide range of specialists, including masons, concrete workers and formwork carpenters, as well as heritage experts such as mosaic artisans and metal restoration specialists. Experts in scaffolding, temporary structural engineering, environmental management and occupational hygiene are also involved.

Pomerleau is leveraging its self-perform capabilities in excavation, formwork, concrete placement, controlled demolition and structural injection. Building Information Modelling (BIM) is also being used to effectively coordinate all activities within this highly constrained environment.

Sustainable Solutions to Protect the Site and the St. Lawrence River

The project incorporates several environmental measures to protect the site and its surroundings. Lead containment is managed through hydroblasting and sealed containment systems, minimizing environmental impacts.

HydroStor retention systems have been installed to improve stormwater management and help protect the St. Lawrence River. Materials generated through demolition activities are sorted and recycled whenever possible as part of a maximum recovery approach.

By prioritizing restoration over reconstruction, the project also helps reduce its overall carbon footprint.

Close Collaboration for Successful Project Delivery

Throughout the project, Pomerleau is working closely with the Jacques Cartier and Champlain Bridges Incorporated (JCCBI) and consulting engineers. Joint planning efforts help minimize traffic impacts and ensure the smooth execution of the work.

Ongoing communication, rigorous monitoring and an active site presence allow teams to anticipate challenges and adapt methods in real time. This collaborative approach makes Pomerleau a true partner in the project's success.

Proud to Preserve a Montreal Icon

Participating in the restoration of the Sainte-Hélène Island Pavilion means helping preserve an important part of Montreal’s history while extending the lifespan of essential infrastructure used by thousands of people.

At Pomerleau, we are proud to contribute our expertise to this unique project, where every intervention leaves a lasting mark on Montreal’s landscape and collective memory.