Exmouth Lifeboat crew were called out to a suspected sunken ship just off Maer Rocks at 9am on Monday.
A fishing vessel had found signs of a wreckage at the mouth of the River Exe and alerted the coastguard. However, the lifeboat crew discovered it was an ageing boat which had drifted out to sea.
Helmsman Roger Jackson said: "We found it was an old day fishing boat.
It seems that someone had tied empty five-litre barrels to it in an attempt to save it.
But it had drifted off into the channel from its swing mooring in the river and we found it broken up in pieces."