Groundwater level time series are available from the FOEN/BAFU
- the general entry point is http://www.hydrodaten.admin.ch.
- The groundwater observation locations are visible here (might work only in Explorer) and a station list including also discharge and lake level stations here.
- No online download, for ordering see here.
Attention: this page lists only Federal resources. Each Swiss Canton might have its own observational network.