MANILA, Daggett County — A Bountiful man died Monday after he fell into Flaming Gorge Reservoir.

Murrell Dale Burningham, 81, was sitting in a lawn chair at Lucerne Valley Marina when he lost his balance as he attempted to stand up and fell into the reservoir, Daggett County sheriff's spokeswoman Karen Peterson said.

Family members pulled Burningham from the water and began performing CPR. Emergency responders continued CPR for 45 minutes after their arrival at the marina, but were eventually directed to stop by doctors at Sweetwater County Hospital in Rock Springs, Wyo., Peterson said.

Authorities are waiting on the results of an autopsy before they release a definitive cause of death. Peterson noted that Burningham had a history of heart problems and had a pacemaker. Family members told investigators that he'd recently experienced episodes of fainting as well, Peterson said.

Burningham graduated from the University of Utah and Creighton Dental School. He practiced dentistry in Bountiful for 45 years, according to his obituary.

Geoff Liesik Twitter: GeoffLiesik