Alexander Christopher Matthew Adams, 23, is the first person to drown in the 500-acre reservoir near Athens, which opened in 2002, authorities said.
"We are still waiting for the official cause of death and the toxicology reports, but it appears that he drowned," said David Cochran, chief deputy of the Jackson County Sheriff's Office.
A couple who live on the lake found Adams' body Sunday evening, floating in a cove in front of their home near Providence Road off Georgia Highway 330. The sheriff's office recovered his body and is investigating his death.
"We still have a few more people to talk to and we're waiting for the results from the lab before the investigation is complete," Cochran said.
There were no signs of foul play, but Adams' body was sent to the Georgia Bureau of Investigation's State Crime Lab for an autopsy. It appeared that his body had been in the lake for several days, Cochran said.
Deputies identified Adams on Tuesday morning; his mother called Athens-Clarke police Sunday morning and reported him missing after not hearing from him all weekend.
Adams was last seen by a friend Friday evening when he left her home in Colbert, according to Capt. Clarence Holeman, commanding officer of the Athens-Clarke police Criminal Investigations Division.
Athens-Clarke police don't know why Adams went to the reservoir, and sheriff's investigators have no indication that anyone else had been with him at the lake.
Bear Creek, located on the border of Clarke and Jackson counties, supplies drinking water to residents of Barrow, Clarke, Jackson and Oconee counties. Fishing is allowed in the reservoir, but it is a no-swimming zone.