Motorists using the Sir John A. Macdonald Parkway will face a year-long detour starting this summer as the National Capital Commission replaces a small bridge.

Starting Wednesday, the NCC will begin constructing a paved, four-lane detour parallel to the parkway near the LeBreton Bridge. It's expected to be finished by the end of June.

According to the NCC, the bridge has reached the end of its lifespan and needs to be replaced.

Sometime in early July, motorists will be redirected onto the detour and the bridge will be closed until the summer of 2020.

While the detour will have the same capacity as the parkway — two lanes in each direction — the speed limit will be reduced from 60 km/h to 40 km/h.

The NCC has allocated $21.8 million to replace the LeBreton Bridge, rehabilitate the Hog's Back swing bridge and resurface the Portage Bridge. The cycling lane on the Portage Bridge will also be widened.

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