RCMP say 23-year-old Dustin Steele of Red Deer was in the vehicle with two other men on Saturday when it was driven into the river.
RCMP say the men tried to pull the truck out of the water by attaching a rope to the back bunker, but abandoned the effort and while two of them swarm to shore, Steele wasn't able to get out of the truck as it drifted away.
The incident wasn't reported until the following day, and while the truck has been located underwater, searchers aren't sure if Steele's body is inside.
The man believed to be the driver was arrested by police on allegations of obstruction of justice and was later released.
Heavy rainfall hampered recovery efforts on Thursday, but searchers hope a break in the weather will allow them to find him. (CFTK)