The Dunedin City Council allocated just over $24 million of capital spending for the complex in its 2021-31 long-term plan, but the upgrade is forecast to exceed that cost.
There is no change to the scope of the Moana Pool upgrade at this stage.
However, information will soon be presented to the council outlining cost escalations and an adjusted budget.
Councillors will need to decide what should be done before they adopt the 2024-34 long-term plan this year.
Moana Pool opened in 1964 and the council has said parts of the buildings, facilities and equipment are deteriorating and due for replacement.
The redevelopment under way includes upgrading changing facilities and renewing assets such as boilers, pumps and water treatment systems.
Work was undertaken in 2022 to tender for new hydroslides and a contract was awarded to New Wave Aquatics.
The council confirmed late last week the contract was on hold while work was being done on "updating the total cost of the pool upgrade work", now estimated to exceed $24m.
This was due to inflationary cost pressures in the economy since the 2021-31 long-term plan was adopted, a council spokeswoman said.
The council was in the early stages of the pool upgrade and work so far had focused on strengthening a wall at the site and providing accessible poolside changing rooms, she said.
There had been cost increases in seismic strengthening work on the external wall at the Stuart St end, because of the discovery of asbestos in the wall.
In its 2022 request for proposals to design and build new hydroslides at the pool, the city council sought plans for two slides, "or preferably more".
"We have asked in the tenders for a minimum of two slides and a variety of ride experiences," community services general manager at the time Simon Pickford said.
"A lift will be provided to the top of the slides, allowing everyone, including people with physical restrictions, to enjoy them."
The council’s pitch to potential partners said the redevelopment project would revitalise the facility for the next 50 years, creating a premier destination for aquatics, leisure and competition swimming in the region.
