Warrnambool police Sergeant Dave McDonald said police executed a search warrant at the pair's Osburne Court property on Friday after the 18-year-old man's father was arrested in Ballarat.

He said the father was intercepted driving and a search of his vehicle uncovered about one-and-a-half kilograms of cannabis.

The drugs have a street value of about $20,000.

"After receiving that information from Ballarat, we executed a warrant at the property in Osburne Court overnight," Sergeant McDonald said.

"Police uncovered three large cannabis plants and a hydroponic cannabis set-up located in a bedroom of the property. It had all the gear - the hydroponic lights and water.

"At this stage we don't know the exact quantity of cannabis seized from the property but it is definitely a traffickable amount."

Sergeant McDonald said the father remained in Ballarat and is yet to be interviewed.

He said the 18-year-old man was released pending summons.

"At this stage we aren't sure if the dad will put his hand up to everything. The 18-year-old may or may not be charged, depending what his dad says."

Anyone with information should contact Warrnambool police or Crime Stoppers.

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