Is it safe to bathe in beaches and rivers? Seina river in Paris Olympic Games 2024

Is it safe to bathe in beaches and rivers? The quality of bathing water

The Seine River has been in the spotlight as the centerpiece of the Paris Olympic Games' opening ceremony and as the venue for the swimming events of the triathlon. The water quality has been a concern for the city of Paris since swimming was banned in 1923 due to pollution from industrial waste and human sewage from an overflowing drainage system. Episodes of heavy rainfall caused sewage overflows, raising levels of bacteria and pathogens like E. coli and enterococci in the river.

For this reason, Paris has made tremendous efforts to clean the Seine's water since 2015, the year the Baignade Plan was launched with an investment of 1.4 billion euros. One of the most emblematic actions to improve water quality has been the construction of a massive 50,000 m³ storm tank beneath the Gare d'Austerlitz station, capable of holding wastewater and rainwater equivalent to 20 Olympic-sized swimming pools. The goal is to prevent untreated water from being discharged into the Seine and its tributary, the Marne, during heavy rainfall episodes. The excess water will be diverted to the sewer system to be treated at a wastewater treatment plant. It is expected that the Austerlitz project will reduce the number of discharge days by tenfold. Decades ago, Paris already managed to reduce discharges by tenfold thanks to the installation of automation and monitoring systems in the network.

Paris' efforts with an eye to the future

The Baignade Plan has not stopped here, but has also included:

1. The improvement of connections between homes and the sewerage network to prevent the discharge of wastewater into the river.
2. The redirection of waste from the pipes of more than 23,000 residences that were discharged directly into the Seine.
3. Modernization of wastewater treatment plants.

Previously, the city banned diesel-powered boats and forced adjacent businesses and boats to install a pipe so that all sewage would not fall into the river.
With this package of measures, Paris has already achieved a tenfold increase in the number of fish species in the Seine compared to the 1970s: 32 versus 3.
The ultimate goal after the Olympics is to open three public bathing areas by the summer of 2025.

 

Rainfall and contamination of rivers and beaches

Heavy rainfall can lead to microbiological contamination of bathing waters by Enterococcus and Escherichia coli (E. coli) bacteria, even though the water is usually free of pathogens and suitable for swimming. Therefore, measuring water quality is an essential tool to ensure the safe use of bathing waters in rivers and beaches, guaranteeing a pathogen-free and safe swimming experience at all times.

Why is it important to detect, control and measure E.Coli and Enterococci?

These are bacteria that normally reside in the human body. The problem arises when their quantity increases significantly. At that point, they can cause ailments such as diarrhea, urinary tract infections, gastroenteritis, or otitis through contact or ingestion.

At Adasa, we believe it is crucial for all types of bathing waters (beaches, rivers, lakes) that the monitoring of these pathogens is continuous and precise, as this is a public health matter. That’s why we have designed an innovative water measurement technology, the aquaBio real-time microbiological control analyzer, ready to operate in both freshwater and saltwater, with solid experience in multiple locations in Europe and around the world. The aquaBio-B503 detects and quantifies in real time, quickly and automatically, the main bacteria that indicate the microbiological quality of water.

In this way, we complement traditional methods that monitor microorganisms for different water uses: bathing, irrigation, and drinking water.

To learn more, click here.