Colac police said a vehicle was intercepted in Colac's Deans Creek Road about 5pm on Saturday.

The 18-year-old male learner driver was not carrying his learners permit and he allegedly tested positive to methamphetamine and cannabis.

Police allege the supervising driver, a 49-year-old Colac woman, also tested positive to methamphetamine - the second time in one week.

The three remaining occupants of the vehicle could not drive and the five people were picked up from the scene.

The pair were two of five motorists allegedly caught driving on drugs in the Colac area on Saturday.

A 39-year-old female from Colac and a 29-year-old Birregurra woman both allegedly tested positive to ice during unrelated intercepts earlier that day.

Then at 8pm, a 33-year-old Corio woman was allegedly found with methamphetamine in her system during a random police intercept in Colac's Queen Street.

All five drivers are facing a loss of licence and fines for drug driving.

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