If you’ve taken off or landed at Toronto’s Pearson Airport since the spring, you’ve seen a giant construction site out your tiny plane window.

Crews have been ripping up and rebuilding Runway 06L/24R, the second busiest runway at the airport — and one of the busiest in Canada. Instead of planes, the three-kilometre long stretch has been packed with excavators, loaders and dump trucks.

Closed since early April, it reopens Friday.

Simon Ho has been overseeing the $80-million rehabilitation project — one of the biggest in the airport’s history.

“It’s an incredible feat,” says Ho, a project manager with the Greater Toronto Airports Authority (GTAA), as a symphony of construction equipment whizzes by him — paving, spreading and compacting asphalt on the final stretch of runway.

The air reeks strongly of tar and asphalt, while planes roar overhead every minute or so. The ground rumbles beneath Ho’s feet — both from the construction and the aircraft.

The rebuild is not far from one of Pearson’s active runways, which Ho’s team had to carefully consider. Crews must stay a certain distance away from the planes. A team of sweepers has to continually clear construction dust and debris. One of the major worries is stray objects getting sucked into aircraft engines.

Ho’s still trying to wrap his head around just how massive the runway is, even though he’s been working on it for months now. 

“You just kind of get the sense that you don’t belong there,” he said. “When you’re standing there, that’s where you really realize this thing is huge.”

Keep reading on cbc.ca