Groundwater levels and spring discharges indicate the status and trend of groundwater quantity conditions. Variations in groundwater quantity are heavily influenced by precipitation and temperature on the surface of the soil.
Groundwater levels in the unconsolidated aquifer reservoirs in the broad flood plains of the rivers Rhone, Aare, Ticino, Reuss, Limmat, Thur and Rhine are further characterised by infiltration from river water. Groundwater recharge in the unconsolidated and consolidated rock in other regions is formed predominantly from seepage of melt water or rainwater – dependent on the elevation. These variable recharge conditions cause typical seasonal fluctuations in groundwater levels and spring discharges, resulting in characteristic groundwater regimes.
Current groundwater quantity status
The status and trend of groundwater levels and spring discharges are continuously recorded at the NAQUA National Groundwater Monitoring groundwater wells and springs. They reflect the weather conditions on the surface, though in attenuated form and subject to a time delay. Long periods of precipitation – especially in winter – increase groundwater recharge. In contrast, sustained periods of drought can result in low groundwater levels and spring discharges.
Trends in groundwater quantity
Long-term weather patterns (temperature and precipitation) in Switzerland are often correlated with periods of relatively low or high groundwater levels lasting for several years. Within this general pattern, significant regional differences are the norm.
Over recent years, the drought of 2011 and the hot summer of 2015 led to unusually low groundwater levels. On the other hand, above-average precipitation in the winter of 2012/2013, summer of 2014 and spring of 2015 resulted in high groundwater quantities.
Niedrigwasser und Grundwasser Synthesebericht (PDF, 3 MB, 01.12.2018)Studie im Auftrag des BAFU
Schadenspotential und Verletzlichkeit von Grundwasser (only available in German) (PDF, 8 MB, 24.02.2009)gwa 2008/6: 459-469 (german)
Last modification 26.03.2019