For the second time this week a chunk of concrete has fallen from the Gardiner Expressway.

The concrete fell onto Parkside Drive near Lake Shore Boulevard at around 10 a.m., narrowly missing a vehicle.

The incident comes after several pieces of concrete fell onto Jarvis Street near Lake Shore Boulevard Monday afternoon.

"I hate to say this, but concrete will crack. Every concrete structure that is built will have cracks and eventually it will corrode," John Bryson, manager of structures and expressways for the City of Toronto, told reporters Thursday afternoon. "We do visual inspections every two years to try to heed these things off, but unfortunately things deteriorate in those two years."

City crews are currently on scene at Parkside Drive inspecting the underpass for loose concrete and a private consultant will visit the site later today to provide advice on how the city can prevent more concrete from falling.

Bryson said he hasn't yet determined the exact size of the chunk of concrete that fell, but has confirmed that it was not structurally significant.

"The concrete that fell here and, I do believe, on Monday is what we call cover concrete, not structural concrete," he said. "If that was the issue there would be more work required than what is going to be done here today."