Parisians and tourists can now swim legally in the River Seine for the first time in over 100 years, thanks to a $1.6 billion cleanup ahead of the 2024 Olympics.
In short:
- Paris opened three official swimming spots in the River Seine near Notre-Dame, the Eiffel Tower, and eastern Paris after decades of pollution made the river unsafe.
- A 1.4 billion-euro investment improved water quality by overhauling the city’s 19th-century sewage system and connecting thousands of homes to wastewater treatment.
- Despite improved conditions, rainstorms still overwhelm the sewage infrastructure, and daily monitoring for bacteria like E. coli will determine whether swimming remains safe.
Key quote:
“What we see is that the water quality in the Seine is highly variable. There are only a few days in a swimming season where I would say water quality is acceptable for swimming.”
— Dan Angelescu, founder and CEO of Fluidion
Why this matters:
Urban rivers once central to city life have long been sacrificed to pollution, infrastructure neglect, and industrial runoff. The Seine’s reopening marks a symbolic and practical shift — one that shows the promise and pitfalls of trying to reclaim nature in urban settings. But it also reveals how vulnerable even massive cleanup efforts remain to climate extremes and aging infrastructure. Rainfall can overwhelm Paris’s combined sewer system, flushing untreated waste directly into the river, creating unsafe conditions overnight. With record heat gripping much of Europe and cities searching for ways to cool off, the health risks from swimming in untreated or poorly monitored urban water sources can be serious.
Related: The Seine’s surprising revival shows what clean water policies can do
