An operational perspective on potential uses and constraints of emerging tools for monitoring water quality

The European Union (EU) Water Framework Directive (WFD) adopted in 2000 requires EU Member States to adapt and to strengthen their monitoring of aquatic ecosystems. New monitoring strategies and practices have to be designed to monitor all polluting substances discharged into the aquatic environment, including priority substances or emerging pollutants that might be present at low concentrations. This requirement implies adapting monitoring locations and density, and monitoring frequency. It might also imply adapting monitoring techniques by integrating alternative screening methods and emerging tools for monitoring water quality to complement existing monitoring.We present the results of five European case studies that explored the potential uses of screening methods and emerging tools for responding to the new monitoring challenges of the WFD under different hydrological and environmental conditions. Combining their technical characteristics with the practical needs identified by monitoring experts and water stakeholders, we identified potential applications and opportunities for operational and investigative monitoring. Advantages of these methods include rapid delivery of results on-site, low-cost and capacity to acquire a larger number of observations within a given (short) time frame.