The river was closed to public swimming in 1923 because of pollution and boat traffic. Credit: Le Sport universel illustré / CC BY-SA 4.0Daniel: I’m DanielMegan Hall: That’s the nephew of our founder. Megan Hall: They just happened to be there when the city reopened the Seine for swimming. Megan Hall: Other Paris residents aren’t so sure about swimming in the Seine. Megan Hall: Daniel says he hopes the Seine clean-up encourages other cities to make their rivers safe enough for swimming.