South-west police road safety adviser Chris Asenjo said Port Fairy officers detected the driver speeding along the Princes Highway at 8.40pm Tuesday.

The driver was issued with a $702 infringement notice, was also fined for not displaying P-plates and banned from driving for six months.

At 7.25am: The need for nuggets overcame the possibility of making proper decisions for a Warrnambool driver during yesterday police national day of road safety action.

South-west police road safety adviser Senior Sergeant Chris Asenjo said Warrnambool Highway Patrol Unit members responded to an erratic vehicle being driven near the east Warrnambool BP service station and McDonald's restaurant.

"The vehicle was located and the driver found to be driving an unroadworthy vehicle while unlicensed. The Holden Commodore station wagon was also unregistered," he said.

The driver told police officers: "I had the munchies. I needed nuggets".

Senior Sergeant Asenjo said that was not an acceptable reason to drive while breaking a numbers of laws.

"The vehicle was impounded at a cost of $1130, that's about $188.33 per nugget," he said.

The driver also faces heavy fines for a number of offences.

Tuesday: Three drug drivers and a motorist travelling at almost double the speed limit were caught in the first few hours of a police national-day-of-action blitz across the south-west.

A Warrnambool highway patrol unit spokesman said a 27-year-old Camperdown district woman was caught in a 60km/h section of the Camperdown-Lismore road travelling at 101km/h on Tuesday.

She was heading north-east in a Toyota Prado when clocked on mobile radar.

The woman will be issued with a $630 infringement notice and lose her driver's licence for six months.

A 29-year-old Camperdown P-plater became the third drug driver caught on Tuesday when he was intercepted just after noon.

South-west police road safety adviser Senior Sergeant Chris Asenjo said Hamilton police members were earlier manning a road block on Ballarat Road when a 27-year-old Hamilton man tested positive to methamphetamine.

A 50-year-old Hamilton truckie, who was behind the wheel of an unroadworthy heavy vehicle, tested positive to methamphetamine or MDMA (ecstasy) use, he said. The samples will be tested before a decision to prosecute is made.

Senior Sergeant Asenjo said mobile police patrols targeted the Corangamite area.

"We've saturated the Corangamite area with mobile patrols. That has been a target area for us because of the significant road trauma in that region," he said.

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A road block was manned at Panmure, where four speeding motorists were detected, an unlicensed driver and 100 preliminary breath tests were conducted

Another road block was set up at Winnap on the Princes Highway near the South Australian border.

Senior Sergeant Asenjo said despite a massive police presence on the roads some drivers were still being caught breaking the road rules.

"People have to understand we'll see them before they see us, and if you're speeding, your speed is often locked in before you get the chance to slow down," he said.

"The messages are clear. Don't exceed the speed limit. Don't take drugs or alcohol and then drive. We will at best catch you, at worst you will die."

The road safety chief said Operation Argus would be held in the first week of September followed by Operation Scoreboard on the AFL grand final weekend.

"While we're asking all drivers to take their foot off the pedal, police members certainly will not be," he said.

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