The 2024 Paris Olympics are scheduled to begin in less than two weeks, though questions still remain about whether the iconic Seine River will be clean enough for athletes to swim in during specific events.

Athletes participating in marathon swimming and triathlons are expected to use the Seine River during the events despite the city previously banning swimming in the river due to concerns about the cleanliness of the water.

Heavy rain would funnel stormwater filled with high levels of E. coli into the river, pushing it above the 900 colony-forming units per 100 milliliters limit that the World Triathlon Federation allows, per the Associated Press.

Paris has now spent upwards of $1.5 billion to build completely new infrastructure to lower the levels of E. coli discovered in the water.

Dan Angelescu, the founder and CEO of the water monitoring company Fluidion, said his company has seen consistent improvements in the Seine River’s cleanliness since Paris opted to spend on the project.

“To see such a drastic improvement and so rapidly could be a sign that something is working,” he explained, per the AP.

Although officials initially claimed that there was no backup plan in case the water was unusable, officials said on July 5 that events could take place in the Marne River if the Seine is deemed unusable at any point, per ABC News.

Additionally, potential changes could include the cancellation of the swimming portion of the triathlon due to a lack of space without the Seine River.

Ollala Cernuda, head of communications at World Triathlon, said canceling the swimming portion is not common but has ” happened a few times” in the past.

“And it’s always linked with water quality issues,” added Cernuda, per the AP.

Regardless, many athletes have come forward and said they would prefer to swim in the Seine if it is deemed swimmable by the time the games begin.

French triathlete Léonie Périault won the bronze medal in the 2020 Tokyo Olympics and said she has a history of swimming in the Seine River and has not had any issues with the water.

“Every time I meet someone, they worry that I’m going to swim in the Seine,” she said, per the AP. “But I’ve been swimming in this river for several years now. In youth competitions, we swam regularly in the Seine and never had problems.”

Ivan Puskovitch, who became only the fifth American in history to qualify for the Olympics in open water swimming, said the “Seine is iconic,” and he hopes that it remains clean within the coming weeks.

“And it would be amazing to say that, like, I was one of the first people to swim in it after such a long time of people being barred from it at the Olympic Games,” he said, per ABC News.

In an attempt to prove that the water is clean, French Sports Minister Amelie Oudea Castera recently decided to go for a swim in the Seine River and has not reported any notable issues, according to USA Today.

The 2024 Paris Olympics will begin with the opening ceremony on July 26. Triathlons are scheduled to begin on July 30, and marathon swimming is scheduled to begin on August 8.