It came minutes after a separate incident where a driver who had never held a licence was found with a 45cm machete in his car.

Police said the vehicle with the illegal imitation handgun was being driven by a man with a firearm prohibition order and who tested positive to drugs.

Officers searched the car, finding a child "aged four or five" in the back playing with what appeared to be an illegal handgun-shaped gel blaster with several broken parts.

"The female passenger from Ballarat said it was hers and she was not aware it was a prohibited item," Sergeant Craig Kelso said.

"The woman was arrested, taken to Ballarat police station, then released pending summons."

Also between 11pm and midnight on Saturday, police said a separate driver was arrested in order to confirm his identity.

"Once it was confirmed he had never held a drivers licence, we also found a 45cm machete in the car," Sergeant Kelso said.

"He was in possession of a controlled weapon and was given a crime penalty notice, which is a very large fine."

The Western Freeway blitz was part of Operation Curdled - a local blitz which overlapped with four-day Operation Fahrenheit, involving State Highway Patrol and other Melbourne-based resources in Ballarat.

Curdled detected three suspended drivers including a man who was clocked at 136kmh in a 100 zone on Old Melbourne Road between Ballan and Gordon.

Police said he was later charged with evading police among other charges.

He is due in the Magistrates Court at a later date.

Officers said they also pulled over a Truganina L-plate driver who not only failed to have a fully licenced person with him, but whose learner permit had been suspended.

DRUG DRIVERS

Sergeant Kelso said three drivers tested positive to drugs - all of them on Friday night - including two for cannabis.

"One driver was from Sydenham and was driving on a suspended licence. He tested positive to ice," he said.

"He'll be due in court at a later date."

When it came to drink driving, one man blew 0.08 per cent.

Police said his car was one of four impounded at the weekend and he has been ordered to front the Magistrates' Court.

In another case, a car without a legally-required interlock device was also impounded.

"The female driver from Pakenham blew 0.49 per cent," Sergeant Kelso said.

"While that is just under 0.05, she had a zero-alcohol condition against her licence, as well as an interlock requirement.

"She told us she was travelling between Pakenham and Avoca (240km) and she and her partner had been drinking.

"She told police she had no money for accommodation, so she had to drive home.

"She'll appear in court at a later date."

Sergeant Kelso expressed disappointment with the number of impaired drivers over the weekend.

"People are still choosing to drive while affected by drugs or alcohol," he said.

"It's not worth it.

"People on drugs are out of their mind if they're driving.

"They're a danger to themselves and everyone else."

Sergeant Kelso said a large number of the weekend's offenders were from outside the Ballarat and Moorabool police services areas.

"Given the stats from us as well as Operation Fahrenheit, speeding is a real problem here

"We have 5 major arterials heading through our police division - that's a lot of people in transit.

"They may not know the road conditions in our area but they may still drive at 110kmh on the freeway."

"The conditions of the road at high speed - plus mixing in alcohol and drugs: it's a recipe for disaster."

He said the Moorabool Police Service Area was now the third worst in the state for fatal road accidents this year.

"144 people have lost their lives on country roads so far this year - and that's compared to 114 on metro roads," he said.

"Please do the right thing."