Warrnambool highway patrol unit Senior Sergeant Cameron Ross said a 31-year-old South Australian man was clocked at the high speed at 11.53am on Sunday.

The motorist was fined $826 and banned from driving for 12 months during the third day of the statewide police operation Amity.

The Great Ocean Road was expecting a peak tourism influx at the weekend due to Australia Day and the Chinese New Year.

"With a driver being caught at 157km/h the safe driving message is still not getting through to some individuals," Senior Sergeant Ross said.

"That driver was detected on a main Victorian tourist route, which is experiencing heavy traffic with many international drivers.

"It's a recipe for disaster ... it's just a complete lack of thought.

"If the smallest thing goes wrong, like a driver pulling out, there would have been a fatality or multiple fatality collision.

"We had far too many deaths on Victorian roads last year and are asking that everyone thinks about their driving behaviour."

Senior Sergeant Ross said in the Warrnambool police service area, covering the Warrnambool, Moyne and Corangamite council areas, police patrolled for 160 hours during Friday, Saturday and Sunday.

Officers conducted 621 preliminary breath tests and a 26-year-old Woolsthorpe man was caught drink driving at .057.

Most of the 73 offences detected involved mid-range speeding, between 10 and 25 km/h over the limit, with four drivers caught above 25 km/h over the limit, who immediately lost their licences.

Senior Sergeant Ross said a number of drivers were also detected not wearing seat belts as police targeted the main causes of road trauma - impaired driving, fatigue, speeding and driver distraction during the four-day blitz.

"It's the Australia Day long weekend. There's a statewide police campaign going on. People know we are conducting a highly visible operation with the aim of reducing accidents and yet people continue to offend," he said.

"We want people to enjoy their time together, but we need drivers to be conscious that we are out there on the roads enforcing the law to try and help everyone get home safe.

"We ask that people be patient, stay alert, make sure that are rested and in a condition to drive and to put down their mobile phones."

Portland and Hamilton district highway patrol police were also busy during the weekend conducting alcohol and drug tests, but no drivers were detected under the influence of alcohol or drugs.

On Friday and Saturday 25 police officers were involved in 68 patrol hours.

A Hamilton police uniform police officer caught one driver speeding at 138km/h on Saturday.

Police are also investigating whether fatigue or alcohol were factors in a collision on the Camperdown-Foxhow Road about 2.30am on Sunday.

A 22-year-old Cobden driver is lucky to be alive after travelling along a road-side drain for 160 metres before his Holden Commodore became airborne and rolled.

The Holden Commodore sedan was heading south towards Camperdown from Ballarat when the sedan left the road and overturned.

The driver was transported to the Camperdown Hospital and then the Warrnambool Base Hospital for assessment and treatment to non-life-threatening injuries, which are believed to include broken bones in a hand and/or arm.

Senior Constable Paul Marsland described the vehicle as an insurance write-off.

"The driver's gone about 160 metres along a drain before striking a cross over, becoming airborne and then rolling," he said.

"He went a long way and was lucky to survive it. We are not sure if he's nodded off (gone to sleep) and that's something we'll be investigating."

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