RedactedNarrative: VESSEL OWNER STATED THAT HE USED THE AQUAMARINA ONLINE SCHEDULER AND REQUESTED HIS BOAT BE TAKEN FROM THE STROAGE RACK AT THE FACILITY AND PLACED IN THE WATER FOR USE ON THE MORNING OF 9-20-18.  AT APPROXIMATELY 1630 ON 9-19 THE VESSEL WAS PLACED IN THE WATER. AT 1730 THE VESSEL WAS FOUND SUNK AT THE DOCK BY ANOTHER MARINA PATRON. OWNER WAS NOTIFIED BY MARINA STAFF THAT THE VESSEL WAS PLACED IN THE WATER WITHOUT THE DRAIN PLUG INSTALLED. VESSEL WAS REFLOATED BY COMMERCIAL SALVAGE AND VERIFIED THE PLUG WAS NOT INSTALLED.