A massive 950‑tonne concrete foundation was lowered into a 35‑metre shaft at Darlington, Ontario, formally beginning construction of Canada’s first new nuclear power plant in more than three decades.. The BWRX‑300 small modular reactor (SMR) project, led by Ontario Power Generation (OPG) with partners GE Vernova, Hitachi Nuclear Energy, Aecon Group and AtkinsRéalis, aims to deliver grid‑connected power for 300,000 homes by the end of 2030.

Darlington’s 950‑tonne slab marks a historic consruction milestone

According to the report, the concrete slab, weighing over 950 tonnes, was lowered into a 35‑metre‑deep shaft using one of the world’s largest crawler cranes. This operation, described by the International Atomic Energy Agency and Mycle Schneider Consulting as the formal start of reactor construction, signals a tangible shift from planning to physical build‑out.

Four‑year, seven‑month deadline pushes OPG to the fast‑track frontier

OPG and its consortium face a tight schedule: four years and seven months to complete the SMR and connect it to the grid by 2030. The source notes that this timeline places Darlington among a very exclusive group of fast‑track nuclear projects worldwide, where even China’s rapid build pace rarely meets a five‑year target .

Workforce and infrastructure: 1,500 workers and a full‑scale prototype

Daily, as many as 1,500 workers are on site building the reactor vessel, containment building, control building, turbine‑generator hall, and an underground water‑cooling network. The project also includes foundations for three additional units that OPG hopes to install in the coming decade.

Historical benchmarks: Canada’s last plant took seven years to finish

The source compares the current build to Canada’s last nuclear plant, completed in the 1980s after just over seven years, and to the Douglas Point project of the 1960s,which took eight and a half years. the fastest historic build, Pickering‑3, required roughly four and a half years during a period of intense reactor construction in Ontario.

Key unknowns: supply‑chain resilience and regulatory hurdles

While the report highlights the ambitious timetable, it leaves unanswered how OPG will navigate supply‑chain constraints and regulatory scrutiny. the success of the project will hinge on delivering on promises, managing logistics, and maintaining a schedule that rivals historic Canadian achievements.