Groundwater resources

The quantity of groundwater in Switzerland fluctuates during the year, but is stable in the long term.

Switzerland is rich in water, but climate change is changing this. Droughts not only affect vegetation and rivers, but also groundwater. The FOEN monitors the effects of drought on Switzerland's natural groundwater bodies and helps to develop sustainable strategies for managing these valuable resources.

Switzerland is rich in groundwater. Groundwater resources occur almost everywhere, both in unconsolidated sediments and fissured or karstified bedrock. They represent an important natural and economic resource.

Groundwater levels and spring discharges usually display a recurring, annual pattern, i.e. a 'groundwater regime', just as rivers follow a 'flow regime'.

The stable water isotopes deuterium and oxygen-18 are natural tracers in the water cycle that can be used to determine the origin of water components and to track climatic changes.

To date, there has been no observable overall increase in groundwater temperature across Switzerland. In certain regions of the country, however, a slight rise in groundwater temperatures indicates the impact of climate change. For example, groundwater temperatures are rising by up to 0.06 °C per year in the Alpine region, in unconsolidated rock outside valley floors in the Central Plateau, and in the Jura. Direct human impacts on groundwater are also leading to measurable changes in groundwater temperature in densely populated areas.