RedactedNarrative: Watercraft #1 (a personal watercraft) was pulling Watercraft #2 which was disabled, at night with no navigation lights. They ran into an emerged tree and Watercraft #1 tipped over. Operator #1 was not wearing a life jacket at the time of collision. Operator #2 (who was wearing a life jacket) grabbed a manual inflatable life jacket and swam out to Operator #1. He inflated the life jacket and gave it to Operator #1. The current was strong and took Operator #1 down river, separating him from the boats. He was still holding the inflatable. Operator #2 then swam back to his boat and called 911. Emergency personnel found both vessels and Operator #2 at about 0115 hours. Operator #1 was found floating in the main channel with severe hypothermia at about 0400 hours. He was transported to the hospital. Deputies talked to Operator #2. He said he had lost power to his outdrive and was able to paddle to shore. He called his dad to help get WC #2 out of the water. His dad showed up on a personal watercraft to tow WC #2. Alcohol was a factor. Operator #1 was charged with operating a personal watercraft after operating hours, operating a personal watercraft without a life jacket, and BWI.