Timboon police Senior Constable Glenn McDuff said there was a lot of roadwork currently being carried out across the Corangamite shire.

Last week there was a report of a driver travelling at 100km/h in a roadworks zone on the Warrnambool-Cobden Road.

Senior Constable McDuff said that on Sunday evening he pulled over a driver on an unsealed section of the Ayresford Road at Brucknell.

The road was subject to a 40km/h roadworks speed limit.

"That driver was liable for his car to be impounded, his driver's licence suspended and a very heavy fine," he said.

"There's a lot of road work being carried out in Corangamite and we are finding that drivers are not obeying the lower speed limits.

"They apply at all times - day and night - and whether there are road workers in attendance or not."

Senior Constable McDuff said the speed limits applied so that repairs that had been completed did not have to be redone by workers the next day.

"If everyone drove at the normal speed through those road work areas the workers would spend a large amount of the next day just repairing what had already been completed," he said.

Late last week a Melbourne man in his 20s suffered a leg fracture after his motorcycle collided with a truck and trailer in roadworks.

Two motorcyclists travelling together and one crashed into the back of a work vehicle in a 40km/h roadworks zone on the Port Campbell-Cobden Road.

It's suspected the motorcyclists were not obeying the 40km/h speed limit and it was very dusty, significantly reducing visibility.

Senior Constable McDuff said roadwork speed limits would be enforced.

"Drivers caught at more than 45km/h above speed limits can have their vehicles impounded and above 25km/h driver's licences can be cancelled for three months," he said.

Have you signed up to The Standard's daily newsletter and breaking news emails? You can register below and make sure you are up to date with everything that's happening in the south-west.