Eau de Paris is responsible for meeting the needs of a vast urban population as well as maintaining high water standards ahead of the 2024 Olympics. As well as maintaining the standard of drinking water produced from river and spring water, there is an increasing need to monitor water quality at a number of new urban bathing sites being constructed in the run up to the games.

The requirement was to detect faecal contamination at water treatment plants supplied from the Seine and Marne rivers and to monitor the quality of drinking water output. Another factor was the safety of competitors during the forthcoming Olympics.

The company elected to trial ColiMinder which measures total microbiological activity or the degree of faecal contamination in drinking water, providing specific measurement of indicator organisms such as E. coli and enterococci. Fully automated, it produces results in 15 minutes with each measurement providing three values:

  • Microbiological activity (degree of contamination)
  • Transmission of the sample (transparency or turbidity)
  • Intrinsic fluorescence

ColiMinder has been used to detect combined sewer overflow from wastewater treatment plants upstream on the Seine, and also for pre- and post-chlorination monitoring of raw water intake. Concurrent testing with traditional laboratory methods showed significant correlation of results with ColiMinder.

The installation of Coliminder has allowed Eau de Paris to close water treatment plants during faecal contamination events whilst providing important information on microbiological water quality.

ColiMinder has also been used in the project to revive the unique second water network in the city that supplies water for street cleaning and irrigating the city’s parks. Having remained unused for 20 years, the system has been re-commissioned. Entirely separate from the drinking water network, it takes non-potable water from the Seine and the Ourcq canal and feeds it through washing outlets in the streets.

The flexibility of the system has allowed Eau de Paris to deploy Coliminder at various locations around Paris and evaluate the benefits of the almost real-time data in the task of safeguarding the city’s water supplies.



E. coli and Enterococci are monitored at Bassin de la Villette

Paris street washing outlet, ‘bouches de lavage’

Paris street washing outlet, ‘bouches de lavage’