High divers plunged back into the River Seine on Friday after a hydrocarbon scare forced organisers to suspend training a day earlier, clearing the way for Paris's first high-diving competition to proceed on its grandest stage.

The divers launched from a 20-metre platform at the Pont de Bir-Hakeim, with the Eiffel Tower standing behind them, as part of the 38th European Aquatics Championships. Traces of hydrocarbons detected upstream on Thursday prompted officials to halt practice sessions. By Friday, the French Swimming Federation confirmed the affected stretch of the Seine had been treated, and athletes returned to the water. The competition is set to conclude on Saturday with the final two rounds and medal events (The Guardian).

High diving — where athletes leap from platforms 20 metres above the water, hitting the surface at speeds approaching 80 kilometres per hour — is one of five disciplines on the Paris programme. More than 1,000 athletes are competing across swimming, diving, artistic swimming, open-water swimming and high diving. The championships run through to 16 August.

This is a centenary edition. The inaugural European Aquatics Championships were held in Budapest in 1926, and Paris last hosted the event in 1931. The return to the French capital has been years in the making, tied to a broader effort to make the Seine swimmable.

Paris invested heavily before the 2024 Olympic and Paralympic Games to clean up the river, including infrastructure to prevent sewage flowing directly into it and upgrades to stormwater management. Maxime Sauvage, Paris deputy mayor for sport, has overseen the city's push to open the Seine for public swimming — a project that has drawn both ambition and scrutiny. Thursday's hydrocarbon detection was a reminder that a urban river carries the residue of the city around it.

For the divers, the stakes are straightforward. The platform is the same height wherever they compete, but the setting beneath it rarely looks like this. High-diving practice at Pont de Bir-Hakeim began on 5 August (Reuters), giving athletes a few days to calibrate their entries against current, wind and the particular light off the water between two of Paris's most photographed landmarks. European Aquatics had scheduled the high-diving events for 7–8 August (European Aquatics).

The scare cost the field a training day. By Friday morning, that was the extent of the disruption. The water passed its tests, the platform stayed standing, and the divers climbed back up.