ACO and TSA advocate to save Ontario Science Centre

Image by BuBZ via English Wikipedia


On April 18, the provincial government announced that it plans to demolish the existing Ontario Science Centre, designed by Raymond Moriyama as one of Canada’s landmark Centennial projects, and construct housing in its parking lots.

The government plans to move the Ontario Science Centre to become part of the redeveloped Ontario Place, in a facility atop an underground parking garage built to service the planned Therme development, as well as in the iconic Cinesphere and Pod complex. Construction is expected to begin in 2025, with an opening slated for 2028.

The Architectural Conservancy of Ontario (ACO) and Toronto Society of Architects (TSA) have issued statements opposing the demolition of the Ontario Science Centre.

The ACO’s statement, written by ACO Toronto presence Stephanie Mah, follows:

ACO Toronto urges the Province of Ontario to repair, restore, and care for the Ontario Science Centre instead of moving it to Ontario Place. This important landmark building is currently listed on the City of Toronto’s Heritage Register, and we request that the City of Toronto designate the building under Part IV of the Ontario Heritage Act as it meets multiple criteria for cultural heritage value under O.Reg. 9/06.

The Ontario Science Centre, originally known as the Centennial Centre for Science and Technology (CCST) at 770 Don Mills Road, has significant cultural, social, architectural, and environmental value. Opened in 1969, the Ontario Science Centre was designed by architect Raymond Moriyama as an Ontario project for the Centennial. It was one of the first interactive science museums in the world and received an OAA Landmark Designation Award. The Imaxdome was added by Zeidler Roberts in 1996. In 2017, ACO Toronto hosted our Annual Heritage Symposium “150+”on Centennial projects at the Ontario Science Centre, where award-winning architect Raymond Moriyama spoke about his experience on the ideas behind the building.

This iconic building has been featured in numerous national publications. In the book Canadian Modern Architecture: 1967 to the Present it is argued that “of all the projects completed under the auspices of the Centennial Commission, Raymond Moriyama’s ‘CCST’ best represents what critic Peter Buchanan described as the heroic period of Canadian architecture.”

Despite this, the building has experienced a severe lack of maintenance in recent years. The pedestrian bridge which links exhibit buildings was deemed unsafe in 2022 and closed. There are no plans in place to repair or replace this structure and visitors are currently moved around the museum via shuttle bus.

Even more concerning is the recent announcement of plans to move the Ontario Science Centre to Ontario Place. While a satellite expansion of the Centre could be explored, moving the entire program from this building puts both the building and surrounding neighbourhoods at risk. The Ontario Science Centre serves as an important community hub in North York and removing it would directly contradict efforts towards sustainable and equitable city-building. The Flemingdon Park, Thorncliffe Park, and larger Don Mills area is already at risk of losing access to another important cultural space: 123 Wynford Drive, another landmark building designed by Raymond Moriyama, originally the Japanese Cultural Centre now the Noor Cultural Centre, which is planned for redevelopment that will demolish much of the building.

We believe through stewardship, care, and community collaboration, additional housing and new amenities can still be provided elsewhere on this site and in the area, while allowing the Ontario Science Centre building to be restored and maintained as a vibrant cultural hub in North York.

The Toronto Society of Architects’ statement, written by Chair Ana Francesca de la Mora, follows:

The Toronto Society of Architects, in fulfilment of our role as advocates for the built environment in Toronto and the surrounding region, calls on the Province of Ontario and Premier Doug Ford to reconsider plans to move the Ontario Science Centre and any potential demolition of this significant architectural landmark.

We take this position on the following principles:

Architectural Significance

Opened in 1969 and originally known as the Centennial Centre for Science and Technology, the Ontario Science Centre is a building of national architectural and cultural significance. Representative of an era of heroic civic buildings looking to establish a unique Canadian architectural identity, it is part of a select group of landmarks across the country built to mark Canada’s centennial. Designed by the celebrated practice Moriyama Teshima Architects, the complex has been specifically built for its site, responding to the changing levels of the Don River ravine and forging an irreplaceable relationship between building and landscape. Its spaces engage all senses, encouraging exploration and physical interaction–a reflection of the science centre’s role as a pioneer of hands-on science education.

Demolishing the Ontario Science Centre would demolish an irreplaceable part of the province’s and country’s history. As caretakers of this landmark, the Province must invest in the repair and maintenance of this facility.


The building and construction industry represent 40% of greenhouse gases emitted in the province. Similarly, a significant portion of the waste filling landfills is caused by the construction and demolition of our built environment. The demolition of the Ontario Science Centre and its replacement with a new structure would generate unnecessary waste and require significant energy and material resources. The climate crisis we face today requires us to acknowledge our collective responsibility to change how things are done and demolition should be a last resort after all other options are exhausted.

Should the Province proceed with moving the Ontario Science Centre, the existing structure should be re-used and adapted to new uses that continue to serve the community. Our city is filled with examples of adaptive reuse projects that have converted much more challenging existing structures to new uses including community spaces, theatres, museums, and more.


The Ontario Science Centre is an important cultural institution and community resource for Flemingdon Park and Thorncliffe Park, dense neighbourhoods that have historically been underserved. This institution plays a vital role as a community hub and is among the few large-scale cultural institutions outside of the city centre.

While our city and province have an urgent need for housing, this should not come at the expense of cultural institutions and community spaces which are essential for the health of neighbourhoods. There are other places better suited for additional housing development.


As a place belonging to all Ontarians, any decision to move the Ontario Science Centre should include extensive public consultation. We have not been made aware of any previous consultation sessions on this topic and urge the Province to allow Ontarians to participate in a debate on the future of the Ontario Science Centre.

The Ontario Science Centre is a shared place of significance for many Ontarians. We firmly believe in the importance of not only retaining, but repairing and celebrating this important architectural landmark and cultural institution and call on the Province to rethink its plans.

As always, we make ourselves available to work together for a better Toronto and Ontario.