More than 500 drones operated by the Australian Traffic Network (ATN) were to light up to celebrate the milestone.

However, 350 drones fell into the river on Friday (July 7) during a light show for the Australian women's national football team's friendly against France before the FIFA Women's World Cup.

A mission to clear the fallen drones is underway after fears of the environmental impact of the battery from the devices.

"We want to see all drones taken back out of the river because we know if they are left there, they will leach chemicals, which can damage the environment," Yarra riverkeeper Charlotte Sterrett told 3AW radio.

"We don’t know the size of the drones but we think it’s the equivalent of 18,000 AA batteries. This is significant."

Divers from ATN, tasked with retrieving the drones, said the incident was the "first technical situation" in 18 months.

"This is the first technical situation we’ve had in the 18 months that we’ve been in the business," ATN's Vic Lorusso told The Guardian.

According to a report, the company will not conduct any more light shows until the problem for malfunction is detected.

Despite the cancellation, Brisbane 2032 Organising Committee chief Andrew Liveris said safety should be the priority.

"We’ve made sure that there are still plenty of ways for people right across south-east Queensland to enjoy the ‘Nine Years to Go’ milestone and celebrate the Olympic rings and Paralympic agitos making their Queensland debut," Liveris was quoted as saying by The Guardian.

"Communities right across Brisbane, the Sunshine Coast and Gold Coast will have plenty of opportunities to see large-scale structures of the rings and agitos and get their photo with them, as well as participate in a range of Olympic and Paralympic sports.

"A host of Olympians and Paralympians will be joining in the celebrations and all of the details, times and locations can be found on local Brisbane, Sunshine Coast and Gold Coast council websites."

Despite the drone show being cancelled, Brisbane 2032 chief executive Cindy Hook unveiled the Olympic Rings and Paralympic Agitos as part of the celebrations.

However, it will only be used "sparingly" until 2027, when the city's commercial rights begins, according to Hook.

"Being able to display the rings and agitos is a privilege of being a host city, a host region as we are in a host nation," she told The Brisbane Times.

"I just hope it’s a way to connect and think about what’s coming.

"Think about the movement, what the meaning behind these symbols is, and hopefully how everybody can be part of this."

The Organising Committee also moved into their office building in Brisbane's Riverside Centre at 123, Eagle Street.

Measuring 147.9 metres, it was the tallest building in the city at its opening in 1986.

At 274m, Skytower is the tallest building in the city.

"Riverside Centre has been an iconic part of the Brisbane city skyline since 1986, with spectacular views across the city that showcase Brisbane at its best," Liveris was quoted as saying by The Brisbane Times.

"This lease agreement will grow with our organising committee over time, ensuring we have a reduced office footprint while our workforce is small in the early days, which can increase to cater for thousands of employees by Games time.

"We’re also pleased that Riverside Centre holds a 6-star NABERS Energy rating and operates on a certified carbon-neutral basis, in line with Brisbane 2032 bid commitments."