Road authorities say it could take months for motorists to adjust to major changes to the way they should enter Perth’s freeways.
New on-ramp merge lines — a broken or dotted line — means entering vehicles must now give way to freeway traffic.
Previously, the vehicle in front had the right of way and motorists were expected to merge “like a zip”.
The changes — which are consistent with most other States — are designed to reduce “conflicts” and congestion, particularly at merge points during peak periods.
Main Roads WA congestion program director James Dobinson said a trial at three freeway on-ramps in 2014 had resulted in more efficient merging and improved traffic flows.
Mr Dobinson said there were three basic rules for entering a freeway from the on-ramp.
“Drivers need to get up to speed as soon as they can, indicate and then move into the next lane just like they are changing lanes,” he said. “It is also important for drivers to be courteous and leave a gap in the traffic or move to the right lanes.”
Mr Dobinson said a behaviour change was needed, though it could take time for drivers to adjust. A short video has been made for social media to help drivers understand the changes.
The new merge lines have been painted at about 30 of the 55 on-ramps on the Mitchell and Kwinana freeways. The rest will be finished over the next two weeks. New lines on some Perth highways are expected to completed by the middle of next year
“To be frank, West Australians do not have a great reputation when it comes to merging,” Transport Minister Dean Nalder said. “By adopting smarter transport options, we can improve merging, reduce congestion and enhance safety.
“A total of $8.5 million will be spent on implementing new on-ramp configurations at over 70 locations on our freeways and highways to help keep traffic moving and our roads safer.”
The latest TomTom traffic index released last week showed Perth drivers spent an extra 102 hours on the road each year because of congestion, up from 72 hours last year.