RedactedNarrative: Operator, along with 4 passengers. was operating the boat going down river on Nickajack Lake in Marion Co near the Bennetts Lake area. He stated they were traveling on the right side of the river as they headed down stream. Operator stated they did not see anything in the water but struck something below the surface. Operator stopped the vessel and raised the engine cover to check for damage. He noticed water coming into the hull so he started the boat and idled over to a shallow water area where a log was so the could sit on the log for safety. Their boat sank while they were on the log. They were picked up and transported to the Bennetts lake boat ramp by a good samaritan.