Construction work on the underground tunnel linking passengers to Billy Bishop Airport is nearly complete, meaning the pedestrian tunnel may open sometime in late July, Ports Toronto said Tuesday.

A firm opening date still needs to be finalized, but Ports officials say they received a certificate of “substantial completion” on the project on May 29, meaning work on the tunnel can focus on the finishing touches.

All but one of the tunnel’s eight elevators is up and running, along with banks of escalators at both ends.

Work on the tunnel’s digital advertising system, installation of safety equipment, installation of the eighth elevator and some tiling still need to be finished before the tunnel can open. Turning circles, sidewalks and curbs on both the mainland and the island are ready as well.

Officials estimate the journey from the mainland through the tunnel to the airport’s check-in area on the island side will take six minutes once the passageway is complete.

Without the tunnel, passengers relied on a ferry that departed each side of the 121 metre channel every 15 minutes. The ferry trip takes 90 seconds.

Ports Toronto spokesperson Erin Mikaluk told CP24 that the ferry will continue to operate once the tunnel is complete, to handle supply and emergency vehicle traffic and also because “passengers have expressed that they would like to keep it.”

Construction of the tunnel took more than three years and cost $82.5 million, paid for through improvement fees tacked onto the cost of travelers’ tickets.