First-time Olympian Ivan Puskovitch is asked some version of the same question all the time: Are you concerned about swimming in the Seine River given all the bacteria in the water?

The 23-year-old American open-water swimmer is one of many marathon swimmers and triathletes preparing to swim in the Paris river during the 2024 Olympics. That is, if it’s clean enough, as doubts about the water quality continue less than a month before the Games.

“My biggest concern, honestly, is just whether the race is going to be held or not,” Puskovitch said at U.S. Olympic swimming trials (in the pool) last month.

“Obviously, health and safety has to come first. It's pretty disappointing that the Olympic organizers have really not locked in cleaning this venue up as far in advance as they should have, to the point where now the whole world is questioning whether it's going to happen in time.”

Swimming in the Seine has largely been banned since 1923, but Paris Olympics organizers vowed to clean the water and bring it to safe swimming standards, including investing $1.5 billion toward the effort, the Associated Press reported last year.

However, as of mid-June, the Seine still contained high amounts of fecal bacteria, including E. coli, making it unsafe to swim in, according to a June 21 report published by the Paris region and Mayor Anne Hidalgo’s office.

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The report and the mayor cited heavy rain, little sunshine and below-average temperatures among the reasons for degraded water quality. And a Paris official said the water samples “do not meet the standards” for competition, according to Le Monde and Agence France-Presse.

Puskovitch, women’s 10k swimmer Katie Grimes and Team USA open water coach Ron Aitken said they haven’t heard of any backup venues, just backup dates. Olympics organizers have been “so adamant,” Puskovitch noted, about not having a plan B venue.

“That's extremely irresponsible,” Puskovitch said. “I think that even if there's a one-percent chance that the race isn't gonna be able to be held because of cleanliness or lack of cleanliness, you need to have a backup plan. It’s the Olympics.”

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Olympics organizers told USA TODAY Sports on Thursday there is a backup venue — Vaires-sur-Marne Nautical Stadium, where canoe-kayak and rowing events will be held — just outside of Paris, should the Seine not be clean enough.

Aitken — who’s also the head coach and CEO of the Sandpipers of Nevada, Grimes’ club team — suspects there is an unpublicized backup venue but that organizers are hesitant to share it because of the hype built around swimming in the Seine.

“I don't think the Paris group wants people knowing that there's a backup plan because there would be everybody saying, ‘Forget it. None of us are going to do this now because we know you’ve got an option.’ I think they want you to think there's no option, especially if they think they've got it under control and it's going to be safe.”

In Paris, Aitken said he’ll offer athletes advice but leave the decision to compete in the Seine or not up to them and their families if there’s no alternative venue. But he’s convinced there is.

“It makes no sense,” he added. “You're gonna jeopardize people's lives or cancel an Olympic event because you don't have a plan B? Give me a break.”

Grimes and Aitken got a preview of the venue in 2023 before the open water test event was canceled — one of multiple canceled because of poor water quality. Aitken said he wouldn’t have let his swimmers compete regardless because of uncertainty about how the water was tested.

Though eager to swim in the iconic river, Grimes said she’s cautiously optimistic but definitely “concerned” about the water quality.

“There's lots of controversy over it because it is dirty water,” Grimes said. “Hopefully they have it all squared away by the time we get there.”

This article originally appeared on USA TODAY: Paris' Seine still isn't safe for swimmers, frustrating Olympians