A 26-year-old Calgary man is dead after a boating accident on Sylvan Lake over the weekend.

He and his girlfriend were in inflatable rafts on the lake 170 kilometres north of Calgary on Saturday night around 7:30 p.m. when they floated just outside the swimming area.

The man jumped into the water to push them both back to shore, but was then unable to get back in his raft.

RCMP said he was under the water for about 20 minutes before emergency crews located him and began performing CPR. 

The man regained a pulse while en route to hospital in Red Deer, but he died on Sunday afternoon

His name is not being released.