A water district employee discovered the truck Sunday afternoon while checking the pond, near FM 2917 and FM 2403.
Investigators believe Donald Copeland, 23, of Alvin was eastbound when the pickup went off the road and into a ditch. The truck became airborne and landed upside down in the pond.
Copeland and two passengers, Olivia Syble Barnes, 37, of Kilgore, and David Earnest Barnes, 36, of Alvin, were dead at the scene.
Investigators don't know the time of the accident, but believe they found the bodies within 12 hours. None of the victims was wearing a seat belt when the bodies were located.
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