Police nabbed 64 people for the offence, putting the city behind only three other cities - Wodonga, where 88 people were charged with the offence, Frankston, 67, and Melton, 66.

Acting Senior Sergeant Dean Greenwood, of Warrnambool police, said while he was not surprised by the high number of offences, it was "incredibly disappointing".

He said police were testing more people, more often to see if they were driving while impaired by drugs.

"We now have the capacity to test people who perhaps previously would not have been tested," Acting Senior Sergeant Greenwood said.

He said he believed more education was needed on the impacts of drug driving.

Acting Senior Sergeant Greenwood said he believed the drink-drive message had got through that you were a "bloody idiot" but some people didn't consider driving while under the influence of drugs was as bad.

"Drug driving doesn't have the same stigma yet," Acting Senior Sergeant Greenwood said.

"We've still got some work to do in the drug driving space."

Acting Senior Sergeant Greenwood said it was frightening as a parent to think that people on the roads were under the influence of drugs.

"We've got the capacity to test more, more often and at more locations," he said.

Acting Senior Sergeant Greenwood said drug drivers had been warned.

"Eventually you will get caught," he said.

Acting Senior Sergeant Greenwood warned that drugs could still be in a person's system days after taking it.

"You can be tested a few days later and still have drugs in your system," he said.

Warrnambool police revealed late last year they were catching a drug impaired driver every day.

The state government's Towards Zero campaign has revealed one in four Victorians who use drugs have admitted to driving while under the influence.

Victoria Police are now conducting more drug tests than ever before, with 150,000 to be carried out in 2019.

Anyone driving with drugs in their system will have their licence suspended for at least six months.

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