I read it was a flat bottom Jon boat some where. Might have hit a submerged rock or stump that is normally in deep water and not noticed. Even in 5 ft of water there I'd imagine it would be tough to stand with that dam killer mud. I've been telling my friends that that lake going so low would some day take someone's life. I've been caught in waist deep mud in that area myself in the dark. Not allot of fun. He could have also been knocked out.