Hamilton police Sergeant Simon Bourke said the woman was intercepted by police for a random check near the intersection of Thompson Street and Henty Highway.

The 36-year-old recorded a positive preliminary breath test and then later at the Hamilton police station an evidentiary reading of just over .13.

Sergeant Bourke said the woman had made a mistake in choosing to drive while knowing she had consumed too much alcohol.

She was fined about $700 and will spend the next 13 months off the road before having to go through the process of getting her licence back.

"We are out on the roads day and night and any driver should be prepared to be alcohol or drug tested at any time," he said.

"This was a decent sort of reading. This was not a miscalculation. We are going to patrol near hotels and see who is coming out, pull them over and test the drivers.

"If you drink and drive you will be caught." he said.

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