RedactedNarrative: Units 1 and 2 were both unoccupied and anchored in the Ashley River in the anchorage area across from Charleston City Marina.  Owner of Unit 1 stated he returned to his vessel from errands to discover that Unit 2 had swung at anchor, changing direction with the changing of the tide, with both units making bow to bow contact.  He moved Unit 1 to Charleston City Marina and contacted SCDNR for an accident report.  I made contact with both owners, noticed small abrasions on the starboard hull of Unit 1, but no damage to Unit 2.