Police have uncovered 350 cannabis plants with a potential street value of more than $500,000 in adjacent to a primary school.
Police are waiting for a botanist and Powercor workers after uncovering the plants at a grow house next to the Grassmere school.
Detective Sergeant Jason von Tunk, of the Portland police crime investigation unit, said Portland and Hamilton investigators, backed by uniform police members, executed a warrant at the Grassmere Road property at 6.30am on Monday.
They found 350 plants, ranging from seedlings to plants ready to harvest, with a potential street value of more than $500,000.
It's the seventh crop house found in the south-west in recent months after similar busts at Warrnambool, Portland, Hamilton and Horsham.
There was also a cannabis drying operation uncovered in a house at Hamilton.
Detective Sergeant von Tunk said Monday morning's bust was another step in the highly successful Operation Highrise.
"It's all part of the same ongoing operation. Today we have made no arrests but we have some follow-up inquiries to make," he said about 10.30am Monday.
"There's an electrical bypass in place and we are waiting on workers from Powercor to attend and make the property safe before we enter.
"There's also a botanist on the way from the Victoria Police forensic unit."
Detective Sergeant von Tunk said Operation Highrise was focused on reducing the cultivation of cannabis in the south-west.
"These crop house raids have netted drugs with a potential street value of about $5 million," he said.
"We expect to make more raids in the near future.
"A number of people have been arrested, charged with offences such as trafficking a commercial quality of cannabis and are now making their way through the criminal justice process," he said.
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