Modernization of the Beauharnois-Les Cèdres hydropower complex

The studies and investigations ended in late 2021. Hydro-Québec has also begun carrying out work on certain structures in the Îles-de-Saint-Timothée Regional Park, the Beauharnois Canal and St. Lawrence River areas.

For more information on the work, please refer to the Priority work section.

Our field studies have continued since then, including the environmental characterization in summer 2026.

The structures of the Beauharnois–Les Cèdres complex were built between 50 and 107 years ago. Under the Dam Safety Act, Hydro-Québec, like all dam owners, is required to carry out safety inspections, studies and assessments on the structures it operates. Given the age of the complex’s components, it makes sense that some work would be required. Based on the studies and investigations, we were able to determine the nature and extent of this work, which will extend the lifespan of the complex by several decades, while respecting the requirements of the Dam Safety Act.

Hydro Québec implements mechanisms to encourage dialogue from the very first stages of a project to ensure a thorough understanding of local realities.

These discussions can take the form of working and consultation committees with territory representatives. They help move projects forward by taking local concerns into account and, whenever possible, integrating those concerns into the proposed solutions. Public consultation activities are then planned to ask the general public for their ideas and concerns.

The concerns and ideas gathered are used to guide discussions before a project begins and to shape project development.

Additional discussions will be carried out to define the host community’s expectations and hopes in order to validate all possible scenarios.

These steps help support the harmonious integration of Hydro-Québec’s projects in the host communities and also promote the reconciliation of land use and collaborative relations.

The public can contact us at any time through the Info-Project Line at 1 866 388‑1978 or by email at affairesregionales@hydroquebec.com.

Hydro Québec has been consulting Indigenous communities through their representatives since 2020 and will continue to do so. These discussions are part of Hydro-Québec’s commitments in regard to Indigenous relations, which stipulate that a consultation must take place at each stage of a project’s life cycle.

The information, consultation and participation activities are aligned with the strategy for carrying out the modernization of the Beauharnois–Les Cèdres hydropower complex and the process of obtaining all required regulatory approvals.

To stay in tune with the residents and their expectations, we encourage ongoing dialogue and a transparent approach. As with all our projects, we are mobilized to find a better balance between community aspirations, environmental and technical realities and constraints and energy needs.

In short, our scalable approach can be summarized as follows:

1. We integrate more variety and flexibility into our approach and tools to support project development. Each project is unique, as are the human and natural environments in which they take place.
2. We focus on ongoing listening, dialogue and creativity in the solutions we propose and strive for the broadest possible consensus.
3. We get communities involved as early on as possible to develop projects that integrate the aspirations of the host community.

The modernization of the hydropower complex involves many interdependent projects that require in-depth analyses from a technical, environmental and social perspective.

Several studies are currently being carried out to better define work scope, priorities and planning. Work can only begin once government approvals have been obtained for each project. We communicate information as it becomes available and as the various projects are defined.

The hydropower complex has ensured reliable water management for over 80 years and has demonstrated its robustness under various hydrological conditions.

Within the context of climate change, modernization projects aim to reinforce that robustness and to ensure even greater resilience for decades to come.

The applicable regulatory requirements will depend on the features of the selected projects.

The ongoing analyses help determine which procedures to follow, including environmental assessments and mechanisms for public consultation, where applicable. Results will be made public as soon as they are confirmed.

Government approvals vary based on the nature and scope of the projects.

Hydro Québec is currently working on defining these issues in connection with the ongoing analyses and applicable regulatory framework.

In the short term, the current project does not include modifying basin drawdown management, which depends on the configuration of existing structures.

However, Hydro Québec plans to continue working to develop its practices in the longer term, particularly by developing solutions that are compatible with optimizing water management.