Carl Jefferson's caretaker had taken him outdoors. At about 4:30 pm, the caretaker called authorities to say Jefferson had gone missing.
The Madera County Sheriff's Office, with help from the Fresno County Sheriff's Office, sent out officers and choppers to search for him.
They found him at 5:30 pm in the water, and he was pronounced dead shortly after.
No alcohol, drugs or foul play are a factor in his death, the Madera County Sheriff's Office said.