The 19-year-old was swimming with a group of others Friday afternoon at about 4:25 p.m. when he was seen going under and failed to surface.
An emergency dive team responded and found the young man about an hour after he went under. He was taken to Providence Hospital in critical condition and later died, said Cmdr. Jeff Goldman of the Marysville police.
There are no signs of foul play at this time, but Goldman said there will be an investigation of the circumstances surrounding the drowning incident.
The 19-year-old's name and hometown were not immediately released.