Improvement of safety and reliability of drinking water quality for Paris: The new implemented strategies of treatments

Countries like France have implemented new European regulations related to water quality and also to find solutions for controlling new emerging parameters such PPP's.

For Paris, the compliance to bromate regulation (10 µg/L) for drinking surface waters has involved the reduction of the ozonation conditions during post-ozonation resulting in a decrease of ozone exposure and the implementation of UV disinfection step. This step permits to compensate the reduction of ozone exposure and to create a second efficient barrier against parasites. In other hand, a survey of different emerging micropollutants such as pharmaceuticals, pesticides from wastewater treatment plant inlet up to pap water has been performed. Results have been used in order to modify the treatment conditions and, in particular, the life time of granular activated carbon.

Concerning the groundwater (representing 50 % of the water used by Parisian), four treatments plants were implemented: granular activated carbon filters and combination of powdered activated carbon/ultrafiltration (100 and 150.000m3/day). These treatments have multiple objectives: the removal of pesticides metabolites and perhaps unknown pesticides, the improvement of microbiology quality after water transportation during up to 150 kilometers and also a security against possible bioterrorism actions.

In other a new pollution protection against pesticides and nitrates has been implanted with local farmers.

The first article of our contract with Paris town is to anticipate the evolution of the new regulations.