Overview
- The city opened three free, lifeguarded swim spots on Saturday at Bras Marie, Grenelle and Bercy for a second straight summer with daily water tests and a green/yellow/red flag system that controls access.
- Officials point to a multibillion-euro cleanup that included new sewer connections and the Austerlitz stormwater basin to cut major sewage overflow events from about 15 a year to roughly two by holding stormwater until it can be treated.
- A heatwave has driven strong public demand for river swimming and the Grenelle site will host open-water events for the European Swimming Championships this month.
- Water quality remains weather-dependent because heavy upstream rain can still push untreated flows into the Seine, so authorities test mainly for E. coli each morning and close sites when levels or currents are unsafe.
- The program revives a century-old river ban and a long Parisian bathing tradition, drew about 100,000 visitors in 2025, and raises public questions about the costs, safety rules, and future of urban river recreation.