Controversy surrounded the Olympic Pool in the Paris La Défense Arena, with critics saying the pool is “slow.”

Every four years, Olympic athletes compete to medal in their sports, a dream surpassed only by setting a new world record. This year was no different, but only a few world records were broken in Paris’s Olympic pool this summer.

Worse still, the Olympians weren’t even as fast as they normally are. Nicolò Martinenghi, the winner of the men’s 100-meter breaststroke, only managed a time of 59.03 seconds (compared to his own personal best time of 55.63 seconds), and this year’s time is actually the slowest winning time in the breaststroke at an Olympic Game since 2004.

At the 2024 Paris Olympics, only four world records were set in the various swimming events.

Compared to the 2016 Rio Olympics, where twice that many world records were set, some say the problem was the pool.

The main issue seems to be the pool’s depth. In Rio, the pool was 3 meters deep. Pools in Beijing 2008 (25 world records) and London 2012 (9 world records) were also 3 meters. The pool-depth standard for World Aquatics is between 2 and 3 meters, with 3 meters being preferred. At 2.15 meters, the Paris Olympic pool is comparatively shallow, and experts say that increases the turbulence that swimmers experience, which makes them a just a little slower.

Turbulence is the big factor, according to Gemma Fleming, a former world record holder who swam in two Olympics for Team Great Britain.

“The deeper the pool, the less turbulence there is between the bottom of the pool and the swimmer,” Flemming told reporters with National Public Radio. “More turbulence means more waves and makes being streamlined in the water harder.”

Built by the Italian firm Myrtha Pools, designers were able to save room for extra seats by making the aboveground pool a little less deep.

Swimmers have said they have no complaints about the pool. And, the arena was packed with fans for every event.

But when waves bounce off the bottom of a pool because of mass movement in shallow water, it typically affects swimmers’ times, which is pretty much what we saw this year.

Credit Myrtha Pools, Paris Olympics 2024.