South-west police road safety adviser Senior Sergeant Chris Asenjo said at noon on Monday that south-west highway patrol units and uniform police had been out in force running Operation Arid during the long weekend.

He said a booze bus had picked up two drink drivers, three men were caught on Sunday morning while another man was detected by Portland highway patrol members both drink and drug driving.

"It's very disappointing - people are clearly not getting the message and they think they can still drink and drive," he said.

"Drink driving is clearly still an issue and something we will focus on across the region in the coming months."

Senior Sergeant Asenjo said that Portland police also received reports about an erratic driver last Thursday night which led to a driver being caught drink driving at more than three times the limit (.18) and drug driving.

"At 8.30am Friday a Hamilton highway patrol unit member clocked a motorist travelling at 127km/h along the Henty Highway near Cavendish," he said.

"That led to a three-month disqualification and a $454 fine.

"At the same time as Operation Arid we've also been running Operation Coverage in the Portland, Glenelg and Southern Grampians areas."

The road safety boss said that operation involved the Transport Accident Commission funding additional police shifts to target speeding on rural roads.

"That's allowed some of those rat run thoroughfares to be targeted for speed with a highly visible presence," Senior Sergeant Asenjo said.

"What's been very pleasing so far is that we've had no significant road trauma in the south-west.

"Maybe detecting drink and drug drivers and speeding motorists has prevented a serious accident or fatality."

So far this year there have been five fatalities in the south-west - at Woorndoo, Allansford, Noorat, Macarthur and Dennington.

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