Concrete fell from the underside of a Highway 102 overpass because of salt water corrosion, according to the Department of Transportation and Infrastructure Renewal (TIR).
“As with any older structure, especially in our Nova Scotia climate, we experience the effects of road salt and salt brine on the concrete. It can lead to a process called delamination – which is ‘spot’ corrosion of concrete where salt water gets into seams,” said Toby Koffman, a communications adviser for the province, in an email on Tuesday.
“Over time, the concrete can come loose. In this case, this structure has had major rehabilitation work over the last 10 years, and the concrete that fell was localized to one area.”
On July 7, a Halifax municipal road crew removed shattered pieces of concrete, including one about the size of a shoebox, off of a boulevard and sidewalk on Ashburn Avenue, which is one street east of Joseph Howe Drive.
“Our bridges are inspected regularly and are safe for travelers, unless otherwise posted,” said Koffman, adding that concrete falling off structures is uncommon.
A TIR bridge maintenance crew has removed any loose concrete from the overpass, he added.
The structure was built in 1963.