Local motorists will have noticed several speed limit changes through intersections between Mandurah and Rockingham.
It's part of a State Government plan to reduce the number of major crashes and save lives on our roads.
Under the change, the maximum speed limit at all intersections with traffic lights across the State will be reduced to 70km/h
Most intersections on Mandurah Road, Ennis Avenue and Patterson Road have already seen speed limits dropped.
A total of 66 intersections will be reduced to 70km/h by the end of this financial year.
In the five years to the end of 2021 there were 82 major crashes where a person was killed or seriously injured at those 66 intersections.
"We're always looking at ways we can improve safety for all road users, and this change is a simple but effective way we can reduce the number of serious crashes at signalised intersections," Transport Minister Rita Saffioti said.
"The vast majority of intersections that will be impacted are 80km/h already, so this is only a small change that will make a positive difference to the number of people killed and seriously injured on our roads.
"This minor reduction in speed, over a short stretch of road is expected to provide a 15 per cent reduction in killed or seriously injured type crashes, making roads safer and savings lives."
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