The Chicago Fire Department said the teen was pulled from the water at North Avenue Beach and was taken to a local hospital in serious condition.
CFD said the teen was drowning at the time of his rescue.
Why the teen was in the water was not immediately known. It was also not immediately known if he was rescued by peers or by emergency responders. It was not clear if a lifeguard was on duty when the incident happened.
No further details about the incident have been released.