Speed limits were reduced on Old Coast Road in Dawesville due to population growth and crash statistics, says Main Roads.
The changes were made on a 13km stretch of Old Coast Road between Egret Point Road, Halls Head to just south of Dawesville Road, in Dawesville, where 390 crashes were reported between January 2017 and December 2021.
A Main Roads spokesperson told the Mail increase in travel time would be less than two minutes.
Repeated speed limit signs as well as two warning signs had been installed to inform drivers of the changes.
Dawesville MP Lisa Munday, who issued a parliamentary grievance on road safety in May, is among several politicians who have campaigned for reductions and road safety improvements.
The changes have caused a stir among community Facebook groups, with some residents frustrated at longer commute times.
Others said there would be less hooning and the new limits would help keep locals safe.
Main Roads said traffic south of Port Bouvard Bridge was already at about 10,000 vehicles per day and the population was expected to continue to grow.
Dawesville has grown significantly in the past 10 years, with a 35.5 per cent population increase between 2011 and 2016.
Residential development has driven construction of new shops, including supermarkets and petrol stations, and public facilities such as schools and a daycare centre.
In the road section that was reduced to 80km/h, there were 36 reported crashes from 2017-2021, many at intersections, and 17 requiring medical attention or hospitalisation.
North of Port Bouvard Bridge sees about 24,000 vehicles per day and many pedestrians.
In this road section, where speed limits were reduced to 70kmh, there were 99 reported crashes from 2017 to 2021, including 10 requiring medical attention or hospitalisation.
"The reduced speed limit will provide a safer road environment for road users and pedestrians," the spokesperson said.
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