Aecon leads C$672 MW Mactaquac hydro rehab through to 2039

Aecon Group and its Mactaquac Improvement Partnership have signed a development phase agreement with New Brunswick Power Corporation to rehabilitate the 672 MW Mactaquac Generating Station, the province's largest single source of hydroelectric power. The partnership, which pairs Aecon (33.3% interest) with FlatironDragados and Green Infrastructure Partners, will spend the next 12 months refining designs, schedules, and cost estimates under an Early Contractor Involvement model before construction is expected to begin in Q2 2027. Completion is targeted for 2039, making this one of the longest-horizon civil infrastructure commitments currently active in Atlantic Canada.

The station, commissioned in 1968, supplies roughly 12% of New Brunswick's electricity and feeds into the wider regional grid. Without intervention, the facility would face decommissioning well short of its intended 100-year lifespan. The civil works scope is substantial: powerhouse and spillway rehabilitation, replacement of all six turbines, electrical and mechanical upgrades, and environmental infrastructure enhancements designed to protect the Saint John River ecosystem. The contract structure uses a target price model for the construction phase, a procurement format that shares cost risk between the public utility and the contractor consortium.

A long-cycle bet on baseload renewables

Aecon CEO Jean-Louis Servranckx described Mactaquac as requiring "world-class experience executing some of the most complex hydroelectric, dam and water management infrastructure projects." The company's hydro credentials are substantive: its portfolio includes the Site C Generating Station civil works and multiple seismic-upgrade and expansion projects with BC Hydro in British Columbia, Ontario Power Generation's Lower Mattagami complex, and the Howard A. Hanson Dam project for the US Army Corps of Engineers in Washington State. That track record positions Aecon as one of a small cohort of North American contractors capable of bidding credibly on multi-decade, gigawatt-scale hydro rehabilitation.

The timing of the deal is not incidental. Across Canada and the broader G7, grid operators are revisiting legacy hydro assets as the cheapest available form of dispatchable clean power at a moment when electrification demand is accelerating. Unlike wind or solar, run-of-river and reservoir hydro can be dispatched on demand, making rehabilitated stations disproportionately valuable to grid operators managing intermittent renewable penetration. NB Power's willingness to commit to a programme running to 2039 reflects confidence that the station's output will remain competitively priced against both new-build renewables and imported power for decades to come.

Cross-sector read-across: infrastructure capital and the energy transition

For investors tracking the convergence of physical infrastructure and the energy transition, Mactaquac illustrates a pattern emerging across OECD grids: the rehabilitation of mid-century civil assets is becoming a structural capital allocation theme, distinct from the greenfield renewable build-out that dominated the 2010s. Long-duration, government-backed infrastructure contracts of this type attract a different capital profile, typically pension funds, infrastructure funds, and sovereign-adjacent vehicles, rather than the growth equity that funds new-build solar or wind. Aecon itself trades on the TSX and carries significant concessions-segment exposure, meaning this contract adds long-dated, inflation-linked revenue visibility that analysts value differently from short-cycle construction backlog.

The deal also signals that Atlantic Canada is becoming a more active arena for large-scale energy infrastructure. As data centre demand, particularly from AI workloads, drives electricity consumption projections sharply upward across North America, utilities holding dispatchable low-carbon generation assets are under increasing pressure to maximise output reliability. The Mactaquac project's 2039 horizon means the rehabilitated station will be delivering power into a grid environment that looks substantially different from today's, one in which clean firm power commands a structural premium over intermittent sources.