Tests show Paris’ Seine River still has unsafe E. coli levels with Olympics less than a month away

The Eau de Paris Monitoring Group’s test results revealed contamination levels consistently above the safe limit of 900 colony-forming units per 100 milliliters set by the World Triathlon Federation for competitions.

Marathon swimming and triathlon events are scheduled to take place in the river near the Alexander III Bridge during the Olympics, which begin on July 26.

Continued rainfall has exacerbated the problem as rainwater infiltrates the sewage system, leading to the discharge of faecal bacteria into the Seine, the report said, adding that flooding of the Yonne River, a tributary of the Seine, increased the flow of the Seine.

A 50,000 cubic meter reservoir, opened in May to store excess rainwater, was used for the first time on June 18 and 19, preventing 40,000 cubic meters of sewage from entering the Seine.

Despite the continued high levels of pollution, organizers remain optimistic.

“By the second half of July, things should settle down,” said Tony Estanget, head of the Paris 2024 organizing committee.

Marc Guillaume, the prefect of the Paris region responsible for the Seine, suggested that the weather would improve in the coming weeks.

“At some point we’re going to have summer time,” he said Wednesday.

“Then the plan will take effect.”

Water quality in rivers in large cities can be affected by many things, from runoff to chemical dumping, sometimes illegally, and boat traffic.