Queen Elizabeth Way was open for the morning commute after a Sunday night accident left the roadway closed for hours.
An eastbound tractor-trailer crashed near Dorval Drive in Oakville just after 9 p.m.
Ontario Provincial Police say the rig went out of control, hit the right cement barrier then went across three lanes of traffic to hit the right barrier.
The wheels came off the trailer and the unit rolled, spilling 200 gallons of diesel fuel.
Some of that fuel spilled into 16-Mile Creek, causing Ministry of Environment personnel to be brought in.
The QEW re-opened about 6 a.m.
Police are still trying to determine what caused the crash.
