River Monitoring
A Work Group of the Saarland University



River Ill

All kinds of water bodies are very dynamic systems. Although this could insinuate their capability to adapt to any new situation, water bodies are very sensitive to harmful impacts. 

Apart from natural seasonal variations occurring in our climate, various parameters of water bodies show evident changes due to different non-natural impacts. Furthermore, not only long term influences but also temporary impacts (especially caused by rainfalls) very often endanger aquatic ecosystems. 

Thus only continuous measurements allowing water analysis with high temporal resolution can shed light on all relevant natural processes and human impacts in surface water bodies.



To understand these phenomena, one needs to consider the variation in time of different parameters and to interpret such data considering many further criteria of the respective catchment. This is why we always include all information available on natural features such as geology, hydrology (water quantity and runoff), weather and climate (precipitations, insolation etc.) as well as human influences (land use, fishery, discharges etc.) in our analysis.
To our understanding this is the only way to distinguish between several possible origins of diverse impacts and River Theelto differentiate charges transported via surface runoff or via interflow or arising from point or diffuse sources. In addition, the distance between a discharger and the measuring station can be estimated, and the permanence of an impact and its consequences can be observed by online measurements at several sites of a stream course. 

Last but not least our measurements and their interpretation also enable us to detect seasonal phenomena as well as natural (basic) concentration levels and thus to estimate the sensitivity of different river parts to impacts and changes.
Exceptional situations in the water bodies can be highlighted by constituting all concentration and load data as averages, maxima and minima for hours, days and months. 
Because of the exceptional significance of the measurements and the interpretation methods that we apply, they are very suitable for evaluating changes occurring in a catchment area as well as for the review of the efficiency of measures carried out to improve the water quality. 
Thanks to their modular concept, the measuring station can easily be adopted to different targets or the measuring devices can be reduced to a few so called tracer parameters.



Our measurements and evaluation methods can serve for:

  • Recording of daily and seasonal dynamics

  • Determination of background concentrations (depending on the catchments)

  • Monitoring of current pollution (implementation of early warning systems)

  • Detection of groundwater pollution

  • Determination of the status of eutrophication

  • Detection of agricultural impacts

  • Detection of impacts from sewage plants

  • Detection of industrial pollution

  • Detection of heat pollution by power plants

  • Documentation of the duration of impacts

  • Estimation of the effect of impacts on the ecological balance

  • Detection of changes caused by modifications of water use

  • Determination of the results of climatic changes

  • Control of efficiency of measures

  • Calculation of absolute loads (e.g. in t per year)

  • Furnishing a calibration base for modelling programmes

and much more