About 300 residents showed up to an open house, saying the facility has been shrouded in secrecy with the company behind it, Tantalus Labs, admitting to not being upfront about the grow-up for legal reasons.
"I'm your neighbour ... I wish I would have never seen your face, simply because this is the wrong place," said Harold Mischke, a Whonnock resident who attended Monday's open house.
Some residents say they had found out about the facility in February and were initially told it was a tree farm.
"You lied personally to me when I talked to you that one day. I'm the one who got two loads of dirt from you," said another upset resident.
When the residents did a property search, they realized it would be a large medical marijuana facility.
"They're like two months away from finishing construction and now we're finding out about this ... and now we're trying to stop this train from getting to the destination," said Sylvie Jensen, a Whonnock resident at the meeting.
Once construction wraps up, Health Canada will inspect the facility to decide whether to grant a licence to produce medical marijuana.
If Health Canada does not approve a license, Tantalus Labs has a contingency plan in place for its facility.
"We're building one of the most technically advanced greenhouse infrastructures in North America. It can be highly adaptive to a variety of different crops," said Dan Sutton, managing director of Tantalus Labs.
He added the facility will create 30 to 50 jobs in the next two years Maple Ridge.
Maple Ridge Mayor Nicole Read said she wants to get concerned residents the answers they need. Health Canada is also reviewing another 12 applications for licensed grow-ops in Maple Ridge.
"[It's] not up for me to determine the merit or future of this industry. Right now my concern is residents who are surprised they're popping up in their neighbourhoods."
Not all residents are opposed. Donald Fisk lives directly across the street from what's being built.
"I don't think there will be only crime because it's got to have a double, chain-linked fence around it," he said.