The National Aquatic Centre, earmarked as the world’s best, was promised by the state government in 2025 to have a seating capacity of more than 25,000 for the Games, with a legacy capacity of 8000.

However several people familiar with the project say temporary seating during the Olympic and Paralympic Games could be axed to keep the cost of building the Spring Hill venue – which must be funded from the $7.1bn infrastructure program – down.

Brisbane’s National Aquatic Centre will still have 8000 seats in legacy mode and be a national hub for Australia’s four peak aquatic sports.

Deputy Premier and Infrastructure Minister Jarrod Bleijie on Wednesday did not say if the capacity of the National Aquatic Centre would be reduced.

“Capacity has been detailed in the Delivery Plan, but obviously, as you would appreciate … we are going through a process with GIICA (Games Independent Infrastructure Co-ordination Authority) at the moment for all the venues,” he said.

“We did ask them to look at the costings because when you appoint architects and designers, they have to do it within budget.

“We’ve been abundantly clear on that.

“What we said we were going to deliver was a National Aquatic Centre that will be the envy of the world.”

However GIICA chief executive Simon Crooks said in Estimates the capacity, as identified in the 2032 Delivery Plan, “remains unchanged”.

“I would point out that we’re going through a project validation report process,” he said.

“You always have a conversation about what is value for money.

“My overriding driver for this is meeting our obligations in the Games and on top of that, meeting the $7.1bn budget.”

Any reduced capacity of National Aquatic Centre would come despite swimming being Australia’s flagship Olympic sport and Los Angeles transforming SoFi Stadium into the biggest-ever, 38,000-seat temporary arena for the 2028 Games.

New artist’s impressions, released on Thursday to mark six years until the Games, reveal the venue will feature a stunning roofline imitating water and wind.

ARM Architecture and NH Architecture, in partnership with Queensland’s Arkhefield, will design and deliver the iconic swimming and water sports centre.

It will have new pools, a gym, high-performance centre and office spaces to complement the existing outdoor pools and amenities of the heritage-listed Centenary Pool.

ARM delivered Perth’s RAC Arena and the redevelopment of Sydney Opera House Concert Hall, while NH Architecture delivered one of the nation’s best sport and entertainment precincts, Melbourne Park.

Arkhefield is responsible for South Bank’s River Quay and the Waterfront Brisbane development.

Four building contractors have been short-listed to deliver the National Aquatic Centre and they will have until the end of the month to submit offers.

The shortlist will be halved before a successful builder is selected by early 2027.

Premier David Crisafulli said Queensland would be ready by the 2032 Games.

“The eyes of the world will be on us in 2032, but this is about delivering legacy benefits for all of Queensland well beyond that,” he said.

“The Centenary Pool is a proud part of Queensland’s swimming history and as a centrepiece for the action during 2032 that history will be strengthened into the future.”

Mr Bleijie said a permanent National Aquatic Centre would deliver a worthwhile sporting legacy long after the Games.

“This design trio will develop an iconic new home for high performance aquatic athletes, as well as a legacy for community sport,” he said.

“This isn’t just a venue for a few weeks in 2032, it’s a lasting investment in Queensland’s future that will support community sport, high-performance athletes and keeping us cool for generations to come.”

The National Aquatic Centre was proposed by Swimming Australia during GIICA’s 100-day venue review, but it was ultimately rejected by GIICA as not fit-for-purpose for Olympic and Paralympic aquatics competition.

GIICA warned the site’s topography “presented significant construction challenges” while an independent assessment concluded costs were “likely to be considerably higher than outlined in the proposal”.

It is understood the topography of the site and location of a 33KV electrical cable beneath it has already challenged planners.

The state government sent GIICA back to the drawing board earlier this year to change the design of the National Aquatic Centre due to cost pressures.

This masthead reported last year the cost of the National Aquatic Centre could pass $1bn, which the government denied.