Alpine Aqualand, part of the Queenstown Events Centre in Frankton, was closed to the public for five weeks last summer when ceiling tiles started falling into pools.
The pool is just over a decade old and cost $18 million to build.
The pools, however, had to be drained last November and 2000 tiles were removed to ensure no-one was hurt.
In a press release, Queenstown Lakes District Council's sport and recreation manager Simon Battrick said the temporary solution of applying tape to a plastic barrier to protect the roof structure was "coming to the end of its useful life".
Mr Battrick said repair items had to be imported from overseas, meaning the earliest remedial work could begin was in September, when the pool would be closed for several weeks.
"Any pool closure is unfortunate and will obviously have an impact on individuals, families, local clubs, schools and our own staff.
"But first and foremost we have to ensure our facilities are safe for all users, which I am sure the community will agree has to be a priority," he said.
On Tuesday, the council's own finance boss, Stewart Burns, made a submission to the annual plan hearing, saying $2.3million was needed for "tile replacement" and "ventilation improvements".
The council will make a decision at a meeting on June 27.
It had been working with specialist contractors on how to fix the problem since the first closure, Mr Battrick added.
"The temporary solution then gave us the opportunity to conduct a building management system review and thoroughly investigate the underlying issue.
"This proved to be insufficient ventilation creating patches of `dead air', especially over the hot pool and learn-to-swim pool."
It would be a major capital project, he said.
The council was looking at options for the public to use pools at Arrowtown or Wanaka, while Aqualand was closed, he said.