La Defense Arena in Paris was transformed into a temporary Olympic swimming venue in just 60 days, reports Judith Wojtowicz.
The home of French rugby, and just days previously the setting for Taylor Swift’s record-breaking Eras Tour, La Defense Arena was transformed in an astonishing feat of technical and architectural engineering.
Two modular 50m pools, made of stainless steel in kit form, were installed in just 36 days. Raised above the rugby pitch, the pools were separated by a giant media stand for 1,000 journalists and broadcasters from around the world. One pool was for warm-up practice and the other for competition, each filled with 2.5 million litres of water.
At 22m high, building the media stand required 20 kilometres of scaffolding served by all the necessary cabling, cameras and lights, fixed to roof, walls and ceiling. A grandstand was constructed for 15,000 spectators. The decision to adapt an existing facility was made after the French bid to host the 2024 Games had been accepted, as part of the organisers’ pledge to create a sustainable sporting legacy.
The original bid had anticipated a purpose-built swimming venue. Denis Navizet, events manager for the Arena, explained: “There were several reasons for the change of direction. “In the past Olympic pools with capacity of 15,000 have become a ‘white elephant’ because they are too big for day-to-day use.”
Rio 2016 was a recent example. The idea of building a pool with a demountable section, like London 2012, was dismissed due to the cost and organisers turned their attention to existing venues that might be converted.
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Adapting Paris La Defense Arena, the largest indoor stadium in Europe, was agreed to be the most reasonable and efficient choice, located not too far from the Olympic Village. The temporary ‘drop-in’ pools will be dismantled after the Paralympic Games, reconfigured as necessary and re-located to provide permanent and much-needed community swimming facilities elsewhere.
Previous Olympic Games, including London 2012, saw permanent aquatic structures built in a way that allowed them to be modified to reduce capacity and provide for wide-community use. Two demountable ‘frame wings’, a distinctive design feature for the 2012 Games, were subsequently removed as part of the building’s conversion into a public swimming pool.
The Paris competition pool also differs in a more significant way… 2.3m deep, rather than the standard recommended three metres. While still being within Olympic guidelines, many people believe shallow water leads to a slower swim, due to the waves naturally generated through swimming. The deeper the pool, the less turbulence is created as the ‘waves’ bounce off the bottom.
Broadcaster Bob Ballard, commentating on his seventh Olympic Games, explained: “There is much debate about the factors that can affect the speed of a race, depth being just one element. It is commonly accepted deeper water makes for a faster swim. Shallower water does seem to slow things down and this was observed by many of us in the stands.
It was notable fewer world records were broken this time, just four compared to recent Games in London, Rio and Tokyo.” He paid tribute to the ‘brilliant’ sight lines and the intimate ambience of the vast space, enabling everyone to feel involved across all the action, regardless of where they were sitting.
“Within the constraints of an existing facility and compared to previous Games where permanent structures were built, I think the organisers did a great job,” he added. Built by Myrtha Pools, an Italian company supplying its sixth Olympic Games, the pools incorporated new eco-friendly features seen for the first time in a competition setting.
The most important of these was their unique gutter system, developed and tested extensively over a three-year period. Pool gutters are commonly used to help keep the water surface flat by collecting overflowing water and so reducing turbulence.
The innovative Myrtha Breathe System is designed to also eliminate pollutants such as chloramines in the air above the surface of the water, which reduces the need for disinfection of the atmosphere. Myrtha describes this achievement as a ‘significant innovation in aquatic sports facilities’ ensuring optimal conditions for swimmers, especially elite athletes striving for the best performance of their career.
French regulations require public pools typically to change 30 litres of water per swimmer daily. It is thought the Myrtha Breathe System will reduce this by 50 per cent, while improving air quality, saving energy and water and reducing the need for chemicals.
The temporary pools of La Defense Arena played host to swimming and the finals of water polo, while a few miles away saw one of just two permanent buildings constructed specifically for Paris 2024. The spectacular Olympic Aquatics Centre (AQC) hosted diving, artistic swimming and the preliminary stages of water polo.
During the Paralympics it was used for the game of boccia, where the aim is to throw the ball as close as possible to the jack. A footbridge was built over the A1 autoroute linking the centre to the Stade de France where much of the Games action was centred. The focal point of the AQC was a 70m pool with moveable floor and bulkheads enabling the pool to be reconfigured depending on the event.
Cecilia Gross, director of Dutch architects Venhoeven CS, told the RIBA Journal this was the first time such pool flexibility has been seen in an Olympic Games. Sustainability and innovation went hand in hand, from the 5,000 seats made from recycled plastic bottle caps to the sculpted roof design made of timber and covered in solar panels.
The roof filters light, collects rainwater and captures the sun’s energy while its concave shape helps minimise energy usage by reducing volume inside the hall. At its highest over the diving tower, the roof swoops down over the pool. To minimise the volume of water required, the bottom of the pool is also sculpted following analysis of minimum depths necessary for each event.
The centre will now become a vast multi-functional sports complex, expected to open to the public next year. As well as swimming it will include a fitness area, paddle tennis and pitches for a variety of team sports, seating between 2,500 and 5,000 depending on the event.
Building on the Olympic legacy, the plan is for the French Swimming Federation to host national and international competitions in the AQC. “All France needs to do now is find a few more Leon Marchands,” said Bob Ballard. “The 22-year-old was a definite beneficiary of these home Olympics, winning five medals including four golds. A great role model and inspiration for the future.”
ESSENTIAL CONTACTS
www.myrthapools.com/en/
www.venhoevencs.nl
