WATER-QUALITY SURVEILLANCE OF SWISS RIVERS

Water-quality surveillance is essential for the detection of anthropog enic impacts on rivers. The surveillance strategy designed by the EAWA G combines longterm, continuous monitoring necessary for assessing the success of measures implemented to fight pollution with short, intens ive field and laboratory studies to elucidate element transformations and transport processes. Emphasis is put on sound methods of sampling and sample processing which are paramount for a clear interpretation o f river quality data. Results from process-oriented case studies show how a combination of different methods of sampling and analysis brough t new insights into phosphorus transport pathways and on the availabil ity of particle-bound phosphate for phytoplankton.