RedactedNarrative: Operator 1 was operating vessel 1 while drifting in the waterway. Operator 1 traveled too close to a sandbar causing vessel 1 to run aground onto the sandbar. Passenger 2 and a witness exited vessel 1 to try to push it away from the sandbar. As vessel 1 was pushed away from the sandbar and began to drift away passenger 2 begin to drift away and was pulled by the current. Passenger 2 eventually was pulled under the water and was later located via a surface search. There was minor damage to vessel 1 from the impact. There was no other injuries from the collision.