With the Seine failing its quality water test, the triathlon format at the 2024 Olympics might be getting a facelift.
The event, which consists of 1500m of swimming, 40km of biking and 10km of running, has been held for men and women since 2000. But if the river in Paris isn't clean enough to swim in, it could turn into a duathlon.
Training in the Seine was canceled for athletes on both Sunday and Monday, and the men's event was postponed from Tuesday to Wednesday after the women's event.
Here's a look at what a duathlon would mean for the Olympics:
Will the Seine be clean enough for swimming at the 2024 Olympics?
As of Tuesday, it's still unclear.
Heading into the Olympics, the water levels appeared to be clean enough for competition. But the heavy rain, which mostly came during the Opening Ceremony last Friday, has worsened the water quality.
Tuesday's men's triathlon was pushed back to Wednesday because the quality water test showed the Seine was still at unsafe levels for athletes.
What will happen if the Seine isn't clean enough for swimming?
Get a weekly recap of the latest San Francisco Bay Area housing news. Sign up for NBC Bay Area’s Housing Deconstructed newsletter.
Organizers say the backup plan is to postpone the triathlon events, which it has already done for the men's event.
If the elevated bacteria levels persist throughout the Olympics, the swimming portion of the triathlon will be canceled and the athletes will compete in a duathlon.
Has there ever been a duathlon at the Olympics?
No, 2024 would mark the first time in Olympic history that there was a duathlon.
The triathlon debuted in the 2000 Sydney Olympics and a mixed relay was added in Tokyo three years ago, but there has never been a duathlon. The event would consist of a 40km bike ride and 10km run, if it is changed to a duathlon.
What Olympic events will be in the Seine?
Five events in total are tentatively scheduled to be held in the Seine:
- July 31: Women's individual triathlon
- July 31: Men's individual triathlon (postponed from July 30)
- Aug. 5: Mixed relay triathlon
- Aug. 8: Men's marathon swimming
- Aug. 9: Women's marathon swimming