Department Water Resources and Drinking Water

In the Tracer Hydrogeology group, our goal is to improve the conceptual and quantitative understanding of interactions between groundwater, surface waters, and groundwater-dependent ecosystems. We build on two fundamental pillars of modern hydrogeological research: (a) various measurements and observations of hydrological and biogeochemical tracers, and (b) the modeling of hydrogeological processes using fully coupled hydrological models (so-called Integrated Surface-Subsurface Hydrological Models, or ISSHM).

We are currently focusing on the development and application of novel hydrological tracer methods and on improving our understanding of groundwater–surface water systems through the explicit integration of tracer data into modeling. The tracer methods we currently develop and apply include both field-based continuous measurements and laboratory-based analyses of:

(a) dissolved gases, e.g., through GE-MIMS-supported analysis of N₂, O₂, CO₂, CH₄, and noble gases, or the measurement of He, Ar, Kr, and Xe isotopes in the noble gas laboratory at ETH Zurich;
(b) naturally occurring radioactive tracers, e.g., ²²²Rn, ³⁷Ar, ³⁹Ar, ⁸⁵Kr, ¹⁴C, ³H, and ³H/³He;
(c) microbial information, e.g., through flow cytometric measurement of total cell counts, LNA and HNA bacteria, and microbial fingerprints, or through sequencing of microbial environmental DNA (eDNA) (16S rRNA amplicon sequencing and whole-genome metagenomic analyses).

Together with the Hydrogeology Research Group and the Applied & Environmental Geology Group of the Department of Environmental Sciences at the University of Basel, the Tracer Hydrogeology Research Group of W+T at Eawag in Dübendorf form the joint Hydrogeology Professorship of University of Basel and Eawag.

The Tracer Hydrogeology Research Group is active member of the Water Earth Systems (WES) PhD school and the Swiss Groundwater Network CH-GNET.