The weapon was found at the Hartland Regional Landfill, about 14 kilometres northwest of Victoria. It appeared to be decommissioned and was marked with the word "inert."
Saanich police Sgt. Steve Eassie confirmed it was designed for one-time use as a surface-to-air weapon.
After it was discharged, the remaining missile launcher would have been nothing more than a harmless souvenir or collector's item.
"It's not so much that this is an illegal item to possess," said Eassie.
However, there are better ways of disposing of these types of equipment. This likely came from somebody who has a collection….and they simply didn't know how to get rid of it."
Police said the rocket launcher originally belonged to the U.S. military, but speculated it may have been used in the 1970s by Afghan rebels fighting Russia.
Eassie said police plan to destroy it and there are no plans to track down whoever dumped the weapon.
Hartland Regional Landfill is the only solid waste disposal facility in the Capital Region and receives about 140,000 tonnes of municipal solid waste every year.