Camperdown police Acting Sergeant Liam Cook said the manner of a 51-year-old Altona Meadows man's driving was so dangerous an off-duty Bendigo police officer took action on the Hamilton Highway near Darlington about 3pm Thursday.

"The off-duty officer was so concerned about the way the man was driving that he intercepted the vehicle," he said.

"The driver later returned an evidentiary reading of .0232 - more than four-and-a-half times the legal alcohol limit."

Acting Sergeant Cook said the man was also driving while his licence was cancelled and his work vehicle was impounded for a month, which would attract towing and storage fees of $1295.

"I don't know if his work is going to be too happy about that," he said.

"The driver attracted the attention of the off-duty police officer because he was swerving all over the road and into oncoming traffic.

"This was a fatal collision just waiting to happen and the officer has to be congratulated for taking the initiative and intervening to protect members of the community.

"Some drivers were being forced off the road in an effort to avoid collisions. It was an extremely dangerous situation."

Acting Sergeant Cook said the Altona Meadows man would be charged with driving while his licence was cancelled, drink driving and potentially other driving-related matters.

He is expected to appear in a magistrates court on a date to be fixed.

The police officer urged members of the public who saw dangerous driving to report it to the nearest police station or Crime Stoppers on 1800 333 000.

"Road trauma is the concern of all drivers and it is only when we all work together that we can achieve our goal, and that is for everyone to get home safely," he said.

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