RedactedNarrative: Watercraft #1 was approaching the gas dock at a marina. Watercraft #2 was fleeting barges up river from the marina. WC #2 was pushed up to a barge and hooking up with the tug in gear keeping tension on the barge. The backwash from WC #2 ended up going in the direction of the marina and WC #1. The current from the backwash pushed WC #1 into the docks causing damage to the dock and WC #1. Four people on the docks at the marina were attempting to hold WC #1 away from the dock to avoid more damage. The deputy spoke to the operator of the tug (WC #2) and he said they were too close to the marina and they normally don't fleet barges that close to the marina. Operator #2 was not aware that the backwash/wake was causing an issue at the marina. There were no injuries associated with the incident and alcohol was not a factor. Life jackets were not being worn.