Toronto reimagining century-old airport into sustainable urban district photo

The redevelopment of Toronto’s former Downsview Airport marks one of the most ambitious urban transformations currently underway in North America. A review by CNN says the 370-acre site is set to become YZD, a 30-year, $30-billion project that will convert a century-old aviation hub into a dense, green urban district housing more than 50,000 residents. The plan reflects a broader global shift toward reimagining obsolete infrastructure as engines of sustainable city-building.

Downsview’s layered history gives the project unusual depth. From its origins as a modest airfield surrounded by farmland, to its role in wartime aircraft production and later as a Bombardier facility, the site has long been tied to Canadian industrial identity. Rather than erasing this legacy, the developers are using it as a design anchor. The airport’s 2-kilometre runway will become a pedestrian park connecting seven neighbourhoods, acting as what Northcrest Developments CEO Derek Goring describes as the project’s “connective tissue,” while “respecting and celebrating the aerospace legacy of the site.”

According to CNN, preserving existing structures is not only about character but climate responsibility. “One of the biggest challenges with large-scale urban redevelopments is when you don’t have anything to start with, they can feel generic,” Goring said. “We want to lean into what’s there and make as much use of it as possible.” 

Retaining the vast mid-20th-century hangars avoids the carbon costs of demolition and new construction. “There’s a lot of embedded carbon in the existing buildings,” Goring explained, “and rather than tearing them down and building everything new, there’s a big carbon benefit to retaining those buildings.”

Environmental thinking extends beyond architecture to landscape and water management. The design of the former runway, led by Michael van Valkenburgh Associates, seeks to “re-naturalise” land that had long been stripped of wildlife to meet aviation safety standards. “The nature within the existing site had to be suppressed so that it was safe for aviation operations,” said partner Emily Mueller De Celis.

The plan now aims to recreate native Carolinian forest habitats, absorb stormwater and reduce flood risk downstream through bioswales and strategic planting.

This ecological focus reflects a growing understanding that urban resilience must be built into long-term development. Goring noted that the project’s 30-year timeline demands flexibility in the face of climate change and shifting social needs. Working with Danish firm SLA, Northcrest is adopting the concept of “City Nature,” prioritising green space as essential urban infrastructure rather than decorative add-on.

Transport planning reinforces this philosophy. Surrounded by existing subway and rail lines, YZD is designed to minimise car dependency, with wide cycling routes and pedestrian-friendly streets. 

“It doesn’t mean there won’t be cars — the runway is really the only car-free area,” Goring said, “But we’re trying to (make) walking and cycling the easiest, safest and most convenient ways to get around.”

CNN situates YZD within a global trend of airport conversions, citing Berlin’s Tempelhofer Feld and Athens’ Ellinikon project. Yet Goring argues Downsview’s location at the geographic heart of Canada’s largest metropolitan area makes it fundamentally different.

“The fact that our site sits at the geographic center of the largest metro area in Canada… means that it’s more of a city-building exercise than a park.”

With construction beginning on the first “Hangar District” in 2026, the project’s success will hinge on patience and adaptability. “The world’s going to change a lot,” Goring acknowledged, stressing that the aim is not to freeze the future but to shape it gradually. Ultimately, he said, “it’s about delivering a really high quality of life… We want it to feel like a part of Toronto.”

By Tamilla Hasanova