In January,France’s Court of Accounts – akin to Australia’s auditor-general – found the estimated cost of the Paris Games had increased by 17.7 per cent since its 2018 bid.

The court raised large questions over the ultimate cost,noting private and public spending was being mixed,foregone revenues were not being accounted for and some expenditures,such as security,were being ascribed to other levels of government.

“In the absence of a comprehensive and accurate inventory of related capital expenditure and operations,both within central government and host authorities,the court is not in a position at this stage to establish the overall cost of the Games and its total impact on government finances,” it found.

Paris,an iconic city that is among the most visited in the world,is not banking on huge economic gains from the Games. But Brisbane has talked up the expected financial pay-off.

The Queensland government says,based on work done by consultancy KPMG in 2021,the Games will boost international tourism and trade by $8.5 billion ($4.6 billion in Queensland alone).

It expects it to create tens of thousands of jobs and $9.1 billion in social benefits across the nation while locking in a decade-long pipeline of construction jobs,trade and investment.

Queensland’s May budget highlighted how easy it is for costs to soar.

Treasurer Cameron Dick set aside $7.5 million over the next four years to “develop the public safety and security arrangement” around the event.

Those eventual arrangements will be picked up by Queensland and federal taxpayers.

Paris is planning to deploy almost 35,000 internal security forces,including police,a branch of the French Armed Forces and private security agents as it seeks to make Paris the “safest place in the world”.

The Paris games are centred on the city of light. By contrast,Brisbane’s games will be spread out across venues on the Sunshine and Gold coasts. Spreading the venues means spreading out security.

Brisbane,nine years away,has already suffered cost blowouts. The original organisational budget was put at $4.45 billion. It now stands at $5.8 billion.

The infrastructure spend has swelled to $7.1 billion. The planned upgrade to the Gabba,originally put at $1 billion,is now estimated to cost $2.7 billion.

US-based sports economist Andrew Zimbalist says the issues that led to the Victorian government abandoning the Commonwealth Games were the same as those confronting Brisbane.

“The situation in Melbourne with the Commonwealth Games is identical to the kind of problems that Brisbane is going to have to face,” he says.

Zimbalist likens hosting an Olympics to building a house – but with much larger possible problems.

A house takes about a year to build. Even then,as Australian construction firms and potential homeowners are discovering,the estimated cost can vary a great deal over 12 months.

An accurate estimate on the cost for an Olympics a decade into the future is almost impossible.

Every Olympics over the past 50 years has suffered a cost overrun. The worst was Montreal (Canada) in 1976 where the eventual cost was seven times what had been originally estimated. It took four decades for Canadian taxpayers to finally erase the bill.

The Rio Games had a cost overrun of 350 per cent,London was more than double,Sydney was 90 per cent more expensive than predicted.

Zimbalist says one of the problems is that organising committees have almost no leeway when it comes to delivering the event. The Brisbane Games start on July 23,2032 and everything is centred on hitting that date.

“You’ve sold the tickets for the stadium,NBC or other broadcasters have set a time down in their schedule to start broadcasting the opening ceremony,” he says.

The true costs of an Olympics can also be hidden.

Athletes’ villages,for instance,are built with the promise of them being turned into housing for a city’s residents once the Games are complete.

There is an obvious incentive to subsidise the construction,either directly through handouts or indirectly via reduced taxes,to get them in place.

One of Brisbane’s selling points is that the Games will lift tourism growth by more than $20 billion between 2020 and 2036.

But previous Games have resulted in a drop in tourist numbers (including Sydney).

Zimbalist says Brisbane will always struggle to win over visitors from the northern hemisphere. “Holding the Olympics in Brisbane is still not going to reduce the flying time from New York,” Zimbalist says.

There can definitely be economic and social benefits from an Olympics. Sydney Olympic Park was,pre-Games,a patchwork of petroleum and chemical waste,unexploded ordnance,asbestos,demolition rubble and garbage.

The 2000 Olympics justified the huge investment in public facilities. When Taylor Swift performs to her sold-out shows next year,they will be held at what was the Olympic stadium. The nearby suburb of Newington rose from the Games’ athlete’s village.

Tim Harcourt,chief economist at the Institute of Public Policy and Governance at the University of Technology Sydney,admits there are large upfront costs with any Olympics.

But he says no economic analysis can pick up the business links struck up while watching the dressage or fencing.

Business Club Australia was established for the Sydney Games as a business networking opportunity. Harcourt says it generated at least $1.7 billion in trade and investment links that continue to deliver benefits to NSW and Australia.

“A lot of people had never been to Australia,and this was a chance for people to see the country,see what it had to offer,and meet and develop business opportunities,” he says. “I call it the power of schmooze.”

Harcourt says,while Olympic infrastructure costs are large,longer-term benefits accrued to a city able to upgrade sporting and transport facilities that may not have been built if not for the Games.

“This is a fast-growing area with increasing demand for infrastructure. The Games will help get that built,” he says.

Supporters of the Brisbane Olympics often cite research by Griffith University academics into the Gold Coast Commonwealth Games of 2018 that found a $2.5 billion boost to the state.

Done in late 2018,the estimated boost covered the period 2013 to 2022. The negative impact of the COVID pandemic,which shut down the economy and international travel,was not calculated.

The Games were estimated to boost employment across Queensland including in the four years after all the cheering had ended. But the post-Games job boost to Queensland was completely offset by a drop in jobs across the rest of Australia.

Separate research by other Griffith University academics found what economists term as displacement.

While tourists from outside the Gold Coast headed to the area to enjoy the event,locals left.

The Games would take tourism to a “new level” with more than a million extra visitors. But the researchers found almost 60 per cent of businesses reported a “severe decrease” in the number of local residents.

The Olympics,according to the Grattan Institute’s transport and cities program director Marion Terrill,are like other “megaprojects”,which are troubling governments everywhere.

This week,NSW Premier Chris Minns cast doubt on the $25 billion Metro West rail project because of worries about its growing price tag.

Terrill says an Olympics is even tougher to manage because the specialist skills to pull together such an event are so rarely used.

“You only have an Olympics every four years,and usually only once a generation in a country. They are not easy to do,” she says.

“Governments are struggling with the mega infrastructure projects they have now. Olympics are much more difficult,with very different skills.”

There’s no doubt that a properly run and successful Games instils huge levels of pride in a community.

It has to. Almost half of the estimated economic benefits from Brisbane will accrue from “social benefits” including civic pride and community spirit.

That civic pride and community spirit will be on display as athletes filter into the Gabba on that July evening in 2032. But it may not be enough to pay for the Games.

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