Festival director Simon Green, in a statement yesterday, said a 24-year-old Queenstown woman would have surgery after fracturing her C7 vertebra during Sunday's competition.
During the event, participants jump from a jetty into Lake Wakatipu.
The woman did not want to be named, the statement said. She is understood to have been in the Winnies Gourmet Pizza Bar team.
A Winnies spokeswoman declined to comment. Mr Green said another member of the woman's team "clipped her head and shoulder" as they jumped into the water.
Initially, the woman complained of a sore shoulder and was helped to shore by water safety officials. A member of the Winter Festival team took her to St John and from there she was referred to the Queenstown Medical Centre, where a doctor prescribed pain medication.
On Monday, the woman returned to the medical centre still complaining of a sore shoulder.
An X-ray then revealed the vertebra fracture, which was diagnosed as "stable".
Further investigations revealed the need for "remedial surgery" which was not expected to result in any long-term complications.
Mr Green spoke to the woman yesterday and said she was in "good spirits".
"For all events, we have a very robust safety plan in place, as part of which all competitors are given a full safety briefing," he said.
Winter Festival marketing manager Mandy Kennedy said the injury was "very, very unfortunate" in what had always been a great event, but organisers would "like to keep it on the calendar".
An internal investigation would include a review of those processes.
Winter Festival health and safety officer Wayne Allen confirmed all entrants had been given a full briefing about how to ask for assistance, how and where to jump, told to look before they jumped, and told not to jump on others already in the water.
Entrants had signed a waiver, in which they acknowledged they were participating in an event "that can carry hazards and may be harmful . . ."
