He later learned that bystanders had directed him to authorities after he overheard news of the sinking.
"I went down to the harbour and I heard two people talking about a boat that had sunk.
I asked them what was going on, and they said what it was, and I said 'My family is on it' - and they said 'Go to the police station'," said Watts.
His aunt and uncle eventually arrived to take care of him during the immediate aftermath.
"I sat in there for what seemed ever and a day, and they took the details," said Watts.
Search efforts lasted for days before all members of his family were finally recovered from the estuary.
"The next morning we went to Dolgellau to the hospital, where they had found three of them - my mother was still missing," said Watts.
His uncle identified his father's body shortly after the disaster occurred.
"My father could swim, but my uncle who identified him said he had had a nasty blow on his head," said Watts.
Watts explained that he frequently passes through the area whenever he travels nearby.
"If I've ever been anywhere near Wales, even when I've been going to Holyhead, when we went to Ireland, I'd come round this way," said Watts.
He expressed relief that a lasting tribute now bears the names of every victim.
"Those 15 people - I didn't want them to be forgotten. Having their names there - that's what I wanted," said Watts.
