Clean rivers help keep cities in the swim

Across North America and Europe, high summer temperatures and low levels of water pollution are prompting city dwellers to dive into a new relationship with their rivers.

Paris, for example, made a splash in 2024 with its rapid cleanup of the highly contaminated Seine in time for hosting the Olympics. This summer, the city opened three areas along the river to the public. (Our intrepid reporter took the plunge recently.)

But other cities have also been consistently cleaning up their rivers. Portland, Oregon, after a major overhaul of its sewer and drainage systems, launched an annual “Big Float” that ran until 2022 to encourage use of the Willamette. This month, Hungary’s capital, Budapest, opened its second swimming beach on the Danube. And each year, more and more European cities participate in the continent-wide “Big Jump,” as rivers get cleaner and their residents gain confidence in the water quality.

In June, the Dutch city of Rotterdam hosted the first “Swimmable Cities” summit. As reported by The Guardian, the city’s vice-mayor noted, “This summit is not just about swimming – it’s about restoring our relationship with water, and leading together toward cleaner, more livable cities.”

Concerted action by city officials and citizen groups has driven the change. When wariness over past pollution makes residents hesitant, the citizen groups educate the public about waterway protections and progress.

Trust in local government becomes a key factor. Citizens count on officials’ continuous monitoring and accurate reporting of negative changes in water quality.

Larger metropolises want to get in on the act, too. London Mayor Sadiq Khan has pledged to make the Thames “swimmable” by 2034, in part by building a “super sewer” that skirts the city. New York City will test out a filtration-assisted, floating pool in the East River next year. Mayor Eric Adams wants to make the most of the city’s natural assets and expand “access to swimming for all New Yorkers, especially our children.”

For young people, such efforts are particularly meaningful.

“Every citizen should feel that urban waterways are theirs to experience and protect,” according to Oumaima Ouaissa, who represented the youth-focused nonprofit Wavemakers United at the Swimmable Cities summit. “Clean and safe urban waterways are not just environmental assets, they are vital spaces for connection, health and wellbeing.”