The metrological stakes of the european water framework directive

Abstract : With the new Water Directive the European Union has given a new dimension to environmental monitoring. It is now necessary to follow and account for the ecological and chemical status of aquatic ecosystems. This status should improve with the objective of "good status" in 2015 for all waters of Member States. Such a regulation will lead to an intensification of chemical contaminants control and has important metrological implications. In order to ensure the comparability of data, it appears necessary to develop internationally validated standard methods and to organise intercomparison exercises for analytical laboratories.