AECOM Joins Ontario Pumped Storage Project in Meaford

Estimated reading time: 5 minutes · Last updated: 8 September 2026

AECOM will support engineering and planning for the Ontario Pumped Storage Project (OPSP) near Meaford, Ontario. TC Energy is leading the project, with Worley and EllisDon on the delivery team; TC Energy expects the OPSP to provide about 1,000 megawatts of generation and roughly 10,600 megawatt‑hours of stored energy. Pumped‑storage hydroelectricity captures surplus power by pumping water to an upper reservoir and later releasing it through turbines, producing discharge over hours rather than minutes. AECOM’s work will focus on underground works, hydraulic systems and design optimisation as the OPSP moves through engineering, planning and regulatory stages.

The Ontario Pumped Storage Project represents an opportunity to apply proven technology at a scale that can help meet the province's future electricity needs

Richard Barrett, Chief Executive of AECOM's Canada region

Why Ontario is planning long‑duration storage now

Ontario’s system planners and developers are preparing for a period of rising electricity demand, and that projected growth is the backdrop for the OPSP. Long‑duration storage—capable of discharging for multiple hours—lets operators shift large blocks of energy from low-demand periods into peak hours, reducing the need for fast-start thermal plants or very large curtailment of wind and solar output. The OPSP is designed to work at grid scale rather than as a short‑term battery: its reported specification of 10,600 megawatt‑hours paired with 1,000 megawatts of output implies multi‑hour discharge suitable for daily or longer peak windows.

Policy and market design questions remain unresolved. The Independent Electricity System Operator (IESO) is reviewing aspects of the proposal—including proposals for a long‑term revenue framework and arrangements for cost recovery—and the IESO's conclusions will influence whether a large pumped‑storage facility can secure predictable returns under Ontario’s market rules. Those commercial signals will affect whether the OPSP progresses from engineering studies into construction.

What AECOM will deliver on the OPSP

AECOM’s role is technical and execution‑oriented within the Worley‑led team. The firm will support advancement of underground works, develop and test hydraulic system designs, optimise constructability and operability, contribute to cost and schedule development, and support formal risk assessment and other engineering activities. Those tasks are core to preparing a large subterranean pumped storage scheme for permitting and later construction.

Large pumped storage projects place particular emphasis on underground civil design and hydraulic control systems because both affect safety, operability and lifecycle costs. AECOM’s global hydropower experience is what Worley and TC Energy have sought for these technical elements; EllisDon will provide Canadian construction and local supply‑chain input. Together the team is intended to close technical gaps that typically slow readiness for financing and regulatory approval.

Local partners, the Saugeen Ojibway Nation and regulatory steps ahead

The OPSP site sits on land in the territory of the Saugeen Ojibway Nation, and TC Energy has positioned the Nation as a potential co‑developer and joint owner if the project proceeds. That relationship is central: negotiated co‑development terms and any benefits package will be part of the project's route to social licence and permitting. TC Energy names the Saugeen Ojibway Nation and links the outcome of those negotiations directly to the project's ability to advance.

On the regulatory side the IESO’s review of a possible long‑term revenue framework and any cost recovery agreement is a named step that must progress in parallel with engineering. Environmental assessment, permitting and Indigenous consultations are typical milestones for projects sited on Indigenous territory; the announcement positions Worley, AECOM and EllisDon to advance engineering while those approvals are sought. Each of those threads—indigenous negotiations, IESO commercial review and statutory approvals—must align for construction to become credible to financiers.

How the OPSP could progress

The bottom line

The AECOM appointment formalises a technical step for the Ontario Pumped Storage Project as it moves from concept into detailed engineering and planning. With 1,000 MW and 10,600 MWh of storage specified, the OPSP targets multi‑hour grid flexibility rather than short‑duration balancing. Delivery hinges on three named strands: the project team’s technical readiness (Worley, AECOM, EllisDon), commercial clarity from the IESO on revenue arrangements, and a negotiated development pathway with the Saugeen Ojibway Nation. If those elements align, the OPSP could become a long‑duration resource for Ontario; if they do not, timing and scope will be at risk.

What to watch

• Watch for the IESO’s decision on a potential long‑term revenue framework and cost recovery approach for the OPSP; no date has been set.
• Watch for the outcome of negotiations between TC Energy and the Saugeen Ojibway Nation on co‑development and joint ownership; no date has been set.
• Watch for TC Energy or the project team to file required regulatory applications or environmental assessments in Ontario; no date has been set.