In recent years there has been a shift from looking not only at the implications of floods in rivers and their impacts on ecosystems but also towards low flows. During the last decades, several low flow periods occurred with severe impacts not only on the river itself but also on different uses of the Rhine. For that reason the International Commission for the Hydrology of the Rhine basin (CHR) with the support of the Swiss Federal Office for the Environment (FOEN), the International Commission for the Protection of the Rhine (ICPR) and the Central Commission for the Navigation of the Rhine (CCNR), thus the three “Rhine commissions” have decided to address this issue in detail by organizing the international symposium „Low flows in the Rhine catchment” on September 20-21, 2017 in Basel with emphasis on science meeting practice. On two days, around 70 participants have acquired an in-depth knowledge on hydro-climatic processes and parameters as well as impacts related to low flows. For example, first results of the ICPR and the CIPMS (International Commissions for the Protection of the Moselle and Sarre) expert groups on low flows as well as information from the CCNR about the impacts of low flows on the navigation were presented. Furthermore, examples of monitoring, management and mitigation measures were shown and resulted in lively discussions between scientists, authorities and users.
In a nutshell, one of the main outcomes of the workshop is that low flows in the Rhine are not being worse than 100 years ago but are nowadays affecting numerous – more or less vulnerable - uses (navigation, industry, agriculture, energy production, etc.). The demand for water and the socio-economic influences are increasing in the Rhine basin. Besides this, low flows, can impact aquatic ecosystems, especially when they occur together with higher water temperature. On top of that, scientists expect more frequent summer low flow events in the future indicating the need for further exchanges between authorities, scientists and water users in the Rhine catchment to improve respective resilience. The results of the symposium will serve as input for future works of the three involved “Rhine commissions”.
The program, the presentations and a summary of the symposium can be consulted here.