The real estate agent started the Tour de Lakes in 1996 after the Glengarry Amateur Cycling Club, which started the original Invercargill to Queenstown event in the 1960s, stopped organising it in 1991.
The increased amount of traffic on the roads around Queenstown, along with the rising costs of accommodation in the resort town and the Health and Safety at Work Act 2015 legislation have made it a difficult event to be run by volunteers.
"Because I work fulltime and my committee works fulltime, we thought where do we go with this?" Dunn said.
"I think it is almost past the point of being able to do it as a volunteer, it is like the traffic volumes are up in Queenstown and Fiordland now they're up by 20 to 30 per cent, the accident rates are rising because of it, the number of tourists about, the extra stress and strain you have got to go through to make sure it runs right."
The legislation requires the riders to be briefed on each stage with potential hazards, while thorough traffic management plans must be adhered to.
"It is a mission, I will put it that way, we have to have a written brief, it is then handed to the Commissaire who reads it and signs it and then it's filed and that happens on every stage," Dunn said.
"But at the end of the day it has survived 22 years now, maybe if it keeps going, we will have to look at where it goes next."
This year has been very testing for Dunn, with each race taking six months preparation, while changes were required for the 2017 version.
The Queenstown Lakes District Council weren't going to sign off the traffic management plan on the Glenorchy Road, but a compromise was reached with the Easter Monday stage five set for a graded mass start from Nugget Point to the top of Coronet Peak, before competitors are driven to Glenorchy for the start of stage six to Moke Lake.
"I start in November with letters to police and sponsors, I follow them up with a phone call for confirmation, then they get an invoice and then the money comes in, then I get the entry forms and the proposed course details up on the Cycling Southland website, it is just ticking boxes really," he said.
"It is quite time consuming, especially when you have local councils looking at a traffic management plan."
"Then there might be changes required, we had a criterium circuit in Cromwell last year, we can't use that this year so now we have to look for another circuit.
"There's a lot of changing in the planning sometimes, unexpected changes and then you have to submit another plan and get it signed off again."
According to Dunn, the increased cost of accommodation in Queenstown has also impacted the event, but he is confident that the four-day, six stage race featuring more than 60 riders competing in A,B and C grades, along with a women's grade, will run smoothly.
"A year ago you could get a hotel room for $100 to $150 somewhere, now you are probably looking at $300, it is the old supply and demand, on the positive side the same people keep coming back year after year," Dunn said.
"I am happy to say it looks like things are coming together."
At a glance
What: Tour de Lakes
Where: Starts Cromwell, finishes at Moke Lake.
When: Friday to Monday
Article and photo courtesy Stuff