Mactaquac Generating Station

As New Brunswick’s largest renewable energy resource, Mactaquac Generating Station is a cornerstone of the province's path to net-zero energy production and integral to its clean energy future.

A run of the river hydro facility with an installed generation capacity of 672 MW, Mactaquac is the second largest generating station in NB Power’s portfolio, playing a vital role in our fleet. It provides 30 per cent of the province’s legislated renewable energy requirements and 20 per cent of New Brunswick’s peak electrical capacity needs.

Mactaquac provides value through clean, low-cost, and carbon-free generation, while offering the flexibility required to integrate other renewable sources, such as wind energy, into the grid.

Mactaquac Life Achievement Project Background

Commissioned in the late 1960s with a 100-year life expectancy, Mactaquac Generating Station’s concrete structures have experienced unexpected deterioration due to Alkali-Aggregate Reaction, which is not unique to Mactaquac. This natural chemical process causes the concrete to expand slowly, resulting in structural misalignment and cracks that impact critical equipment, including spillway gates and turbines.

In addition, aging mechanical and electrical equipment must be replaced, and improvements must be made to fish passage systems.

After evaluation of several alternatives, including full decommissioning or the construction of a new facility, and a comprehensive public engagement process, it was determined that rehabilitating the existing station through the Mactaquac Life Achievement Project is the most affordable and reliable path forward.

This recommendation follows several years of expert research, including input from scientists, engineers, the public and First Nations. This approach will meet all provincial and federal safety protocols and environmental protection requirements.

We are grateful for the many partners we have on this project, helping us make it a reality for the benefit of our province for decades to come. These include First Nations, construction companies and our Shareholder.

Project Benefits

The Mactaquac Life Achievement Project is a vital investment in New Brunswick’s secure energy future, ensuring this cornerstone of our grid continues to provide clean, reliable power for generations to come.  

Without major intervention, the Station would require increasingly costly maintenance and would likely cease operations by 2030. If Mactaquac were taken offline, NB Power would need to find alternative generation sources to ensure energy security for New Brunswickers.

The proposed Project also offers significant economic benefits, in terms of local jobs, materials, housing and construction costs.

Proposed Schedule

Mactaquac Life Achievement Project activity is scheduled to begin in summer 2026 with essential site preparation.

To maintain grid stability throughout the project, we will take a phased approach, beginning with the removal and replacement of the first generating unit between 2028 and 2029. 

The project is expected to be complete in 2037–38. The long schedule reflects the need to keep most of the plant operating safely while the work is underway to ensure New Brunswickers have the energy they need when they need it. 

Anticipated Project Timeline

Regulatory Approvals

In order for the MLAP to proceed, there are a number of checks and balances, as well as regulatory approvals, in place to ensure this is the best project for our province and that it will bring value.

In July 2023, NB Power submitted the Mactaquac Life Achievement Project for review under New Brunswick’s Environmental Impact Assessment legislation. The Project EIA reflected years of meaningful work, careful planning and collaboration, including important consultation with First Nations communities. The application was approved in June 2025.

In order for this project to proceed, the following additional approvals are required:

NB Power will continue to respect the regulatory process and share updates with customers throughout this process.

More information

As this is a major, decade-long project, NB Power will continue to engage and share information with New Brunswickers every step of the way. For example, any impacts on local area traffic or the river due to construction will be shared well in advance to ensure limited impacts on roads and waterways.

Financial statements reflecting overall project costs will be publicly available in quarterly and annual reports. However, current estimates, including interest and inflation over the life of the project, are expected to be between $7.6 and $9 billion.

You can learn more about the project through these resources:

• Download project fact sheet

More questions?

For more information on the Mactaquac Life Achievement Project, contact us at mactaquac@nbpower.com.