Contra Costa Fire Protection District Capt. Robert Marshall said the boy's friends had tried to save him but the current proved too strong, the Contra Costa Times reported.
The boy's body was recovered about 4:45 p.m. PDT, about 2 hours after he fell in. The name of the victim, who was from Antioch, was being withheld pending notification of relatives.
Marshall said it wasn't clear how the teen wound up in the water, but he and his friends may have been playing in the area.