AWWA WQTC52881

In the autumn of 1999, nanofiltration (NF) was introduced in the Mery-sur-OiseWater Treatment Plant as an additional refining step downstream fromflocculation, ozonation, and dual media filtration. This plant feeds adistribution system that supplies water to 31 cities in the northern suburbs ofParis, France. NF 200 membranes were selected for their ability to remove naturalorganic matter and atrazine. Eighty percent of the water produced by thistreatment plant if nanofiltrated, with the remainder being biologically treated.Results of the full-scale data demonstrate that the distributed water quality wasimproved by the new treatment, with total organic carbon at the plant outletbeing lower than 1 mgC/L, total bacteria number decreased by 49%, andtrihalomethanes by 50%, when compared with the results obtained over the sameseason prior to the installation of NF. Includes 17 references, table, figures.