Toronto's Pearson International might become one of the world's mega airports if ambitious new expansion plans are realized over the coming years.

The Greater Toronto Airports Authority (GTAA) has released preliminary designs for a sprawling new transit centre, passenger processing area, and retail complex that would radically transform the airport and surrounding area.

The CBC touts the integrated transit hub as "a second Union Station," which is a bit outlandish given that only one rail route currently terminates at Pearson (the UP Express), but it does gesture to the scale the GTAA is thinking of here.

The forward-thinking hub could eventually connect to the Eglinton Crosstown, the Kitchener GO Line, and a variety of bus lines in Mississauga. That would help get some of the 300,000 people who work at and around the airport out of their cars and onto public transit.

Right now, statistics indicate that only seven per cent of people who work at the airport use public transit. The number climbs to 10 per cent for travellers, but that's still well below other international airports.

Activity at the airport and its surrounding area gives rise to roughly one million car trips a day.

Still, the expansion would be about more than just creating a regional transit centre. With passenger screening on site as well as retail and hotel space, the new addition would function as a gateway to the existing terminals and offer a whole new commercial element to Pearson.

The centre is proposed to be built on Airport Road across from Terminals 1 and 3 on a site that's predominantly surface parking at the moment.

Funding for the project has yet to be secured, though the GTAA reports having had preliminary discussions with all levels of government.