Drivers crossing the Canso Causeway between Cape Breton and mainland Nova Scotia will be detoured in the coming months.

The detour will allow for repairs to the 60-year-old swing bridge that lets boats through the canal. Andrew MacPherson, project engineer with the Nova Scotia Department of Transportation, says the detour bridge should open by mid-November. It could be in use until as late as May 15.

"We're going to be installing a temporary detour," said Andrew MacPherson, project engineer with the province's transportation department.

"And that's going to move traffic to the north side of the bridge. So all vehicular traffic will use the temporary bridge starting at some point in November."

The detour bridge is expected to open by mid-November. (Yvonne LeBlanc-Smith/CBC)

Last phase of project

MacPherson says with traffic diverted, some of the steel components on the top side of the existing bridge will be replaced. The old operator's building will also be removed.

"The operator's building is an old building. It's located above the bridge, so it actually kind of hangs above the traffic that crosses the bridge. So we're going to remove that, and that's going to provide a little more clearance for vehicular traffic," he said.

A new operator's building, located on the northwest approach to the bridge, is almost complete.

The work is the last major phase in the $8.9-million rehabilitation project.

The canal will be closed to marine traffic for an extended period this year starting Nov. 1, to accommodate the construction of the detour.

The canal is scheduled to reopen in May 2017.