Early Warning Systems on the Rhine and Elbe in Germany

Abstract

Intensive monitoring of European rivers allowed a control of the different types and amounts of contaminants. In a river flowing through several countries into a small sea like the North Sea, a reason for monitoring is to obtain knowledge about the source and amount of contamination and to identify responsibilities. Monitoring of rivers is a difficult task because the investigation must be done during day and night and during certain weather events, such as high floods or low water discharges. It must include accidents and normal discharges. Measurements in a river transect requires us to know how the water flows in this sector, while taking samples should allow a calculation of the whole water body. In the case of an accident, it should be possible to analyze the contaminant and trace it back to the source. It is not only the chemical analysis that needs to be monitored, but it must also include ecotoxicological effects and special investigation programs, e.g. the examination of living fish. Monitoring a river is an expensive but necessary way of improving water and sediment quality.