River Seine ‘Teeming’ With Life

Decades of restoration efforts are yielding positive results as dozens of species of fish return to the once-polluted waterway.

1 minute read

February 11, 2025, 9:00 AM PST

By Diana Ionescu @aworkoffiction


Man sitting in chair along River Seine in Paris with fishing pole.

Man fishes in the River Seine, Paris, France. | ARB.shoot / Adobe Stock

After years of being “biologically dead,” Paris’ River Seine is alive with fish and other marine life, reports Peter Yeung in Reasons to Be Cheerful.

In fact, in the 1970s there were only three fish species left in the 777-kilometer (482-mile) river, which spans northern France and cuts through the capital city. But after decades of urban water policies alongside community efforts, there are now nearly 40 that have been officially registered, with new species turning up all the time.

The city vastly improved its wastewater treatment system starting with its first strategic plan in 1929, leading to better water quality in the once-polluted river. The river was finally deemed safe for human swimming in 2024, just in time for the Summer Olympics. The city will also open three public swimming sites along the Seine in summer of this year.

“Yet recognition must also be given to the associations of fishermen in Paris, who, mostly on a voluntary basis, have been monitoring fish populations for years, as well as adopting sustainable practices such as banning fishing in reproductive seasons,” Yeung adds. However, challenges remain as new pollutants, climate change, and invasive species slow European cities’ progress in cleaning and protecting urban rivers like the Seine.

Monday, February 3, 2025 in Reasons to Be Cheerful

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