WLR_Special: The International Commission for the Hydrology of the Rhine Basin (CHR) and its activities

The Rhine, which flows over a distance of 1,233 kilometres, from the Alps to the North Sea, is an important lifeline for Western Europe. A multitude of users depend on the Rhine for an adequate and clean water supply, while maintaining a healthy relationship with the natural environment and its ecosystem.

One of the three Rhine committees is the International Commission for the Hydrology of the Rhine Basin (CHR). The CHR is an independent scientific body, through which the relevant authorities of the Rhine’s riparian states cooperate. The participating countries are Austria, Switzerland (also representing Liechtenstein), Germany, France, Luxembourg and the Netherlands. The CHR was founded in 1970, partly due to UNESCO and the WMO directives, within the context of the ongoing “hydrological decade”. The CHR is an organization in which the scientific institutes of the Rhine riparian states formulate joint hydrological measures for sustainable development of the Rhine basin.

Key working themes within the CHR are climate change, socio-economic activities (concerns water use) and sediment. This session will further explain these themes through some relevant projects:

1. Concerning climate change, in recent years we have studied the melting of ice and glaciers in the Alps and its impact on Rhine discharge. Here the focus was not only on the past (last100 years), but also on the future (next 100 years).
2. Changes in socio-economic activities may lead to changes in water use and water consumption, and also influence the discharge of the Rhine river. Therefore we integrate the available information on water users and evaluate the relevance of changes in water use and consumption by the individual sectors on the distribution of the discharge of the Rhine river.
3. Human interventions in the morphology (channelization) and in the sediment regime have dramatically changed the flow and especially the sediment transport of the Rhine. In order to optimise the efficiency of spending on countermeasures we recently conducted a basin-wide study to current sediment issues, research and monitoring. Current work also focuses on effects of climate change on the sediment balance and understanding trends.