Portion of Highway 401 near Milton to be fully closed Saturday night

An Ontario Provincial Police officer attends a scene in this file image.

Drivers will have to find an alternative route Saturday, as Highway 401 is expected to be closed both ways overnight.

The highway from Guelph Line to Regional Road 25 will be closed for 12 hours, beginning at 9 p.m.

Additionally, the Ontario Ministry of Transportation said on-ramps onto the highway will be closed from Guelph Line and Regional Road.

In a social media post, Halton Region said drivers will have to detour to Campbellville Road in the meantime. Police and other traffic control will be in place, along with detour signs.

The region said the closure is in place for construction crews to safely demolish the old Tremaine Bridge, which overlooks the highway. A new bridge was opened on July 7.

The closure is expected to end at 9 a.m. on Sunday.