Ontario installs first Darlington SMR foundation in precision lift milestone

Ontario’s push to make small modular reactors look buildable, financeable and on schedule just cleared a major hurdle at Darlington. A 2.1-million-pound basemat module for Unit 1 was lifted and set in place at the Darlington New Nuclear Project site on April 30, a precision move Ontario said marked the first foundation of a new nuclear reactor built in the province in more than 30 years.

That matters because this is the kind of milestone investors, regulators and utilities can actually count. Ontario used one of the world’s largest crawler cranes to place the module with millimetre precision, and the project is now far enough along that the work is no longer just about licensing language and renderings. It is about heavy civil construction, module fabrication and the discipline needed to turn SMR promises into steel and concrete at the existing Darlington Nuclear Station in Clarington.

The Darlington New Nuclear Project is being led by Ontario Power Generation and is planned for up to four reactors at the site. The Canadian Nuclear Safety Commission lists one unit under construction, and OPG said in March 2026 that it applied for a Licence to Operate for the first SMR, a step required to finish commissioning and begin safe operation. Ontario approved construction of the first unit on May 8, 2025, framing it as the G7’s first small modular reactor and, in the province’s telling, North America’s first commercial grid-scale SMR.

The project’s scale explains why this lift landed as more than a ceremonial moment. Ontario has said electricity demand is expected to rise by at least 75 per cent by 2050, and it has tied the Darlington buildout to 18,000 construction jobs, 3,700 operating jobs and $38.5 billion in GDP. The province has also put about $20.9 billion on the project’s overall price tag, with the first reactor later pegged at about $6.1 billion and another $1.6 billion for systems and services shared across all four units.

Ontario has been building the industrial base around the site at the same time. In October 2025, the province announced a $1 billion investment through the Building Ontario Fund. It also said GE Vernova Hitachi Nuclear Energy would invest $70 million in a BWRX-300 engineering and service centre in Durham Region, and that BWXT’s Darlington nuclear work was valued at $960 million over seven years. Against that backdrop, the basemat install is the kind of proof point the Western SMR market has been waiting for: not a slide deck, but a foundation that is actually in the ground.