The incident happened at 10:45 a.m. on Friday, June 30.
The boy, age 17, was a resident of Cortlandt Manor, said state police.
His body was recovered by the Rockland County Sheriff's Office Marine Unit, said Trooper AJ Hicks.
State Police said there were no signs of foul play detected at this time.
The Rockland County Medical Examiner assisted at the scene.
Click here to follow Daily Voice Armonk and receive free news updates.