Northbound traffic on Highway 400 slowed for hours after a large dump truck went off the roadway and rolled deep into the ditch about five kilometres north of Canada's Wonderland amusement park.
However, police said the highway open by about 6 p.m.
Helicopter images from the scene south of King Road on Friday afternoon showed the truck, which had been carrying a load of top soil, at rest just above a large culvert.
Emergency responders have tried to secure the vehicle to keep it from falling further down the slope.
The Ontario Provincial Police told CTV News that the accident seems to have occurred after the truck blew a tire, adding the vehicle rolled at least once or twice.
The driver didn't appear to be seriously injured, as he was up and walking before paramedics put him on a backboard for transport to hospital.
An air ambulance helicopter had been sent to the scene as a precaution, but it wasn't needed.
A heavy-duty tow truck was at the scene. By 4:30 p.m., it had the truck up to the highway's shoulder.
One northbound lane had been opened up to allow some traffic through. The OPP also diverted traffic at Teston Road.
To add to the woes, southbound traffic on Highway 400 was affected by a collision near Major MacKenzie Drive. The three-vehicle crash affected two lanes.
