Warrnambool Highway Patrol Acting Sergeant Jo Wastell said a Warrnambool woman, 55, blew 0.233 after she pulled into a driveway to avoid a breath test site on Raglan parade on Friday night.

"It is absolutely astounding," Acting Sergeant Wastell said. "It is definitely one the highest we have had around here in a while."

Police suspended the woman's licence, impounded the white station wagon, and she is expected to appear in the Warrnambool Magistrates' Court on summons.

"I can't even image trying to drive at that point," Acting Sergeant Wastell said. "It is very frustrating especially with the way the road toll is, people are still doing stupid things."

She said police caught three drink-drivers with readings over 0.1 in the past week.

Two people also tested positive for using illicit drugs while driving, a 24-year-old Warrnambool man on Friday night and a 39-year-old Peterborough woman early Sunday morning.

Police are awaiting the results of laboratory testing before they proceed with further action.

Acting Sergeant Wastell said police were catching more people drug driving because illicit substances remained in drivers' systems for longer, and drugs such as methamphetamine remained accessible.

"Maybe the mentality is they won't get caught but you never know where we are," she said.

Meanwhile, Colac Highway Patrol officers caught two drug drivers in Colac on Saturday morning.

Police had intercepted the first male driver on Murray Street when a second male verbally abused the other while driving by.

The drivers, aged 27 and 29, both tested positive for initial drug tests and provided a further oral fluid test.

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