The current World Water Speed Record holder has announced he is building a new boat in Newcastle in a bid to challenge his own record-time, set more than 30 years ago.

Ken Warby set the current record at Blowering Dam in the Snowy Mountains in 1978 by reaching a speed of more than 510 kilometres an hour.

Many people have died trying to better his time but he is planning to do it himself with his son Dave, an experienced boat builder.

The boat is being constructed in a workshop in Merewether and Dave Warby says he is confident it is capable of breaking the record.

"A lot of people who attempt this record don't really come from a boat racing background," he said.

"They have a quick look at it and think, 'if an Australian like Ken Warby can build a boat in his backyard and break a record', he makes it look very easy, but there's actually quite a lot of technical work in the background.

"I really think the boat we're building now is more than capable of breaking the record."