Main Roads have released a two stage plan to fully open the bridge this month.
The Mandurah Bridge traffic lane layout will be changed to fully open in two stages this month.
On Wednesday December 6 traffic was moved onto the two outside lanes of the bridge to enable final road works to be completed safely on the new bridge.
During this temporary arrangement, the northern lane is carrying east-bound traffic, and the southern lane is carrying west-bound traffic.
Stage two will happen before Christmas, with all four lanes open to traffic.
Traffic management signage will be in place at all times to guide motorists.
Removal of the old bridge is continuing and will be completed in January 2018, then landscaping, path and boardwalk works will continue through to February.
Main Roads have released this picture, showing traffic flow in stage one, and then stage two when the bridge is fully operational.

Fresh new look for Roger May Machinery Museum
Tragic end to search of missing FIFO worker
Accused arsonist charged over Bertram fires
Bondi Beach Statement
Police issue 31,000 driving infringements in first month of new AI cameras
Works underway on Rockingham and Safety Bay High School redevelopments
New measles exposure sites revealed in Bunbury
Dawesville man charged after allegedly leaving his elderly Great Dane to suffer painful conditions
Good Samaritan sought by police after helping teen during robbery in Baldivis