"I know I won't,'' Mr Martin said.
The family was in Central Otago for the day and up until the accident, it had been a good day.
"It was a s... end to a fantastic day.''
Jack was the youngest of four children and, like his older siblings, he lived for sport.
"He was riding a push-bike without training wheels before he turned 3, he was on a motorbike when he was 4.
"He had extraordinary balance for a young lad and whatever he did, he excelled at.''
He had made the Otago rugby under 48kg team for the past two years and was player of the year this year.
He was also talented at cricket.
"He is supposed to be playing for North Otago at the South Island Primary Schools Cricket Tournament in Dunedin next week and he's not going to be there.
"I'm not going to see him do that.''
Mr Martin did not agree with calls for a ban on boats on the lake, saying he had "no issues'' with how the lake was run.
"There was probably only two boats on the lake at the time.
"It was just an unfortunate, horrible, accident.
"It's just one of those things that went wrong.''
Contrary to previous reports that said Jack died after being flown to Dunedin Hospital, Mr Martin said he died at the scene and was then flown to hospital.
A family friend and sports coach, who did not want to be named, said he was a "good, humble kid'' and his death would devastate the Waikouaiti community.
"The family is one of the better families you would ever meet, too.
"It's a tragedy, it's horrible.''
The accident was being investigated by Central Otago police and Maritime New Zealand.