The Banks Peninsula farmer was elected chairman of the Canterbury A&P Association (Capa) board at its annual meeting in Christchurch.
He said the "iconic" show week running since 1862 was part of Christchurch and Canterbury and would not exist without a strong show.
"So it’s been stopped by world wars and Covid-19 and I’m not going to see it stop because of the precarious financial position."
Sir David said the goal was to run a good show this year and build momentum for next year with a long-term ambition to cement it back into place for "at least another 160 years".
New board members had arrived knowing the finance director announced at the annual meeting the show’s financial position was "precarious", he said.
"So we have gone in with our eyes wide open, but with the determination ... and the support of our urban and rural community this show can survive and in fact it can prosper."
Other shows breaking even or making a small profit in a single day with a smaller attendance showed it was possible to do this with a three-day show attended potentially by 100,000 visitors, he said.
The new board planned to put a tight rein on costs and was asking the public to buy early tickets and going to business people, sponsors and trade exhibitors about providing financial backing.
To return to a strong financial position and be a long-term success, volunteers and other show supporters needed wide support, he said.
"My phone has been red hot today with people saying this is wonderful and we want the show to survive. Well it won’t survive with lip service. It will only survive if everyone gets behind it.
"It’s an important connection between rural and urban and we have got to make sure we don’t destroy that linkage and that’s what I’m determined to do by making sure the show survives."
Sir David said when he heard there was talk of not having a show this year he was "absolutely dismayed".
The last show had lost a lot of money and there was no point dwelling on postmortems as there was a need to move forward positively, he said.
"The show is a fundamental part of Christchurch’s history — it has been running in some form since 1862 and is the longest-running agricultural show in the South Island. While it is called the Christchurch show this year, we want to return to the New Zealand Agricultural show in 2025. The show is literally the country coming to town."
Sir David has been a member of Capa for 50 years and has a long history of serving the rural community politically and at governance level.
He was about 17-years-old when he first attended the show. A member of the association since at least 1972, he was an exhibitor as a Simmental breeder for about 10 years until committing to politics.
He said backing already received from local businesses was positive.
"Our event partners Event Hire are underwriting parts of the Christchurch Show, and we can’t thank them enough. They have stepped up and said the show must go on."
Christchurch mayor Phil Mauger said there were solid plans in place to ensure its longevity.
"This is part of our history, and it is important that it continues for our city. So, I hope that everyone will get behind it and get to the show rain, hail or shine. As a community we need to support this iconic event."
Event Hire co-owner Phil Anderson said they were shocked when they heard the show wasn’t going to run.
He said while the show would be scaled back slightly all the things people loved about it would still take place.
Livestock displays, stock judging, trade sites, competition events and entertainment would continue.
To bring the crowds in, the entry price has been halved for for adults to $20 for adults and Event Hire is seeking a sponsor to subsidise the cost of children tickets.
In another change the show will be shifted to Thursday, Friday and Saturday, rather than Wednesday to Friday.
Mr Anderson said this would reduce previous queues and parking pressure on the traditional last day of Friday.
Sir David said long talks had been held with Christchurch City Council managers which had assured the board of its full support and appreciated the value of a healthy show continuing for the local community and economy.
He said the lesson from previous years was the need for the show community working constructively with the board.
"There is a general committee which is large, but it’s made up of very dedicated show people and in the past that general committee has had a dysfunctional relationship with the board. The board I put together is now 50% independent members and 50% general committee members. That sort of trust in each other and co-operation between the general committee and the board is going to be absolutely essential to get the show working."
Independent directors elected on the board were Hazletts operations manager Peter Engel and BDO audit senior manager Ethan Hill, who were joined by Bryce Murray, Brent Chamberlain and Lex Peddie from the general committee.
