A senior Olympic official promised the water quality will get better soon, with the first triathlon event set for Tuesday in the Seine. The Seine as an Olympic venueThe Seine was the star of the show at the opening ceremony on Friday. Enlarge image (new window) Paris mayor Anne Hidalgo, top, swims in the river Seine along with Paris 2024 organizing committee official Tony Estanguet earlier in July. Début du widget Widget. Fin du widget Widget.