The river, a central element and highlight of this year's Games, has been affected by a stormy May, leading to the cancellation of the 27 May rehearsal after an earlier one on 8 April. "It will take place when the weather conditions allow for it," officials told AFP.

The Paris Olympics are scheduled to open on 26 July with a boat parade on the Seine, marking the first time a Summer Olympics will kick off outside a traditional athletics stadium. However, the ambitious plan is considered high-risk. The Seine is also set to host open-water swimming and triathlon events during the 26 July until 11 August Games, contingent upon reducing pollution to safe levels in time for the athletes' arrival in just over 60 days.

Officials have repeatedly cautioned that heavy rainstorms before or during the Games could overwhelm Paris's sewer system, potentially causing discharges of untreated sewage into the river. Recent data collected by the water charity Surfrider in mid-May revealed E.Coli bacteria levels exceeding the authorised limit by more than four times, indicating significant human waste contamination.

Paris authorities and Olympic organisers assure that new infrastructure, including a wastewater treatment plant and a rainwater storage facility, will be operational by the start of the Games. Cleaning up the Seine is considered a key legacy of the Paris Games, with Mayor Anne Hidalgo promising three public bathing areas for locals next year.

A new poll released on Tuesday has added to the organisers' concerns, showing a significant drop in the percentage of French people planning to follow the Games. Only 51 percent of respondents surveyed by Toluna Harris Interactive said they intend to watch the events, down eight points since January and significantly lower than interest levels in other regions.

In contrast, 71 percent of respondents in Japan and South Korea, and 68 percent of Americans and Europeans, expressed plans to follow the Games. Paris 2024 organisers maintain that pre-Games anxiety and negative media coverage are common in host countries. They remain optimistic that the "iconic" locations across the French capital, along with domestic sporting achievements, will inspire enthusiasm and national pride once the Games commence.