Commonwealth Games 2022: Birmingham attempts to leave 'carbon neutral legacy'

The Commonwealth Games begin next week and will involve athletes from 72 nations and territories taking part in the biggest sporting programme in the event's history.

Around 6,500 competitors and officials will travel to Birmingham for the Games, which feature 19 sports and eight Para-sports and run from 28 July to 8 August.

The scale of the event provides plenty of challenges, chief among them the question of how to stage a global sporting competition in an environmentally sustainable way.

These Games take place almost exactly a year after a major United Nations report warned of the need for deep cuts in global greenhouse gas emissions - and just over a week after UN secretary general António Guterres told governments the world is facing "collective suicide" in the face of deadly heat extremes.

With all this in mind, the organisers of Birmingham 2022 have committed to making this year's Games "the most sustainable yet".

So what issues do they face, what are they doing and do their claims stand up to scrutiny?

The major challenges facing global sports events

The Alexander Stadium was opened in 1976 and has been redeveloped for the 2022 Commonwealth Games, where it will host athletics and Para-athletics

The Commonwealth Games is far from alone in trying to find ways to host a major event while also mitigating the environmental impact.

The football World Cup in Qatar later this year is estimated by organisers Fifa to produce around 3.6m tonnes of carbon dioxide, which would be more than some countries' annual emissions.

"Global sporting events have a huge impact on the environment," David Goldblatt, a researcher investigating the relationship between sport and the climate crisis told the BBC's Costing the Earth programme.

"There is an enormous amount of carbon in the construction that goes into staging an event. Then there's a lot of lighting, pumps, air conditioning, a huge amount of food and drink.

"There's also the transport, with a large number of athletes, media, fans and officials often travelling long distances to be involved."

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What are organisers doing to make Birmingham 2022 sustainable?

Construction of venues, as well as travel, energy and food are the biggest contributors to any event's carbon footprint.

Birmingham 2022 will take place across 15 venues, with a focus on renovation and development of existing sites.

Established venues such as Arena Birmingham will host gymnastics, Coventry Arena will stage judo and wrestling and T20 cricket will take place at Edgbaston.

"Ninety-five per cent of the venues are being reused," said Jess Fidler, head of sustainability for Birmingham 2022.

"There's been some rejuvenation at Alexander Stadium [athletics and Para-athletics] and at Sandwell [diving, aquatics, swimming and Para-swimming]. But every other site already existed and that reuse and repurpose is absolutely key from a sustainability perspective."

Fidler said Commonwealth Games organisers want their approach to leave a "carbon-neutral legacy".

"We've measured our footprint using the best data available and we've focused on the hotspots of transport, energy and food to drill down into how we can reduce those emissions," she said.

"When you buy your Games ticket public transport is included, so that's a way of encouraging people out of their cars. That's a great way to reduce the footprint of the Games but also to get people thinking about using public transport generally.

"There has also been a big focus on local, seasonal food. Some of the caterers are doing carbon labelling [making clear the environmental impact of producing a specific item]. There's been a big focus on waste, using biodegradable food packaging and people knowing what to put in what bin. Small changes like that can make a big impact.

"We've also created a partnership with Severn Trent [water company] from an offsetting perspective where they will plant 2,022 acres over a period of time and that will offset the emissions of the Games."

Carbon offsetting is controversial, with some scientists and campaigners saying it can be a barrier to behavioural change.

"The current forecast is for those 2,022 acres to sequester 240,000 tonnes of carbon, which at the moment is about two thirds of our footprint," said sustainability officer and ex-England hockey player Joanna Leigh, who views the planting of the Commonwealth Forest as one important part of the Games' strategy.

"We'll measure our final footprint at the end of the Games and that will be verified by a third party. If we are a little bit over then we'll make sure we top up that 240,000 tonnes with credible carbon offsets."

Are organisers doing enough?

The question is whether organisers of major events are doing enough - and whether what they say they are doing has the impact they hope for.

"I'm really delighted that these are serious documents [the sustainability plans and pledges] but there are quite a few problems," said Goldblatt, who adds that the 2004 Athens Olympics and 2014 Sochi Winter Olympics are examples of ambitions not being met.

"The first is that these can be used as a get-out-of-jail-free card.

"The second is many offset schemes in the past have proved to be unsuccessful - reforested trees have not grown, they weren't planted properly in the first place and the claims collapse.

"Also, many of these reforestation and carbon capture schemes will do their best work in 30 years or more and we really need to make massive and significant change over the next 10-20 years."

Severn Trent says the estimated period for offsetting the 2022 Games is 35 years.

Dr Russell Seymour, chief executive of the British Association for Sustainability in Sport, told BBC Sport Birmingham 2022 is "setting a high standard".

"They have taken a comprehensive approach to sustainability," he said. "Birmingham have approached this in a methodical way. They have been very clear in what they can and can't do and realistic also in the way they are reporting [their data]. They're very careful to avoid any kind of 'greenwash'.

"They are being clear that, yes, there are going to be impacts, but they're doing their absolute best to try to mitigate those. Birmingham 2022 is probably doing more than many other major events have."

So is there more organisers of these Games could be doing?

"There are lots more things we'd like to do with more time and more resource," added Leigh. "Hopefully in the future we'd have a fully electric fleet of vehicles - we haven't got that because the market can't supply those yet.

"There's no perfect offsetting solution but ultimately we are taking responsibility for the carbon we produce. We are trying to be as transparent as we can be."

Fiona Burnet, who plays hockey for Scotland and is a member of EcoAthletes, told BBC Scotland: "Birmingham is a really positive example where they are trying to have a carbon-neutral legacy.

"They are taking steps which are really positive and hopefully other major events will look at Birmingham, a multi-sport event with 72 countries, and think 'if they can do it then why can't we?'.

"If we want to enjoy these huge events in the future then changes need to be made."