It happened in Reading.
Witnesses say he was swimming near Blair Avenue and Montgomery Street around 5:00 p.m. when he went under.
He wasn't found for another 15 to 20 minutes.
Rescuers had to climb down a steep embankment to pull him out of the water.
Medics performed CPR and rushed him to the trauma center at Reading Hospital.
He was pronounced dead a short time later.
