Linking baseflow separation and groundwater storage dynamics in an alpine basin (Dammagletscher, Switzerland)
- 1WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland
- 2Geological Institute, ETH Zurich, Sonnegstrasse 5, 8092 Zürich, Switzerland
- 3Department of Environmental Systems Science, ETH Zurich, Universitaetstrasse 22, 8092 Zürich, Switzerland
- 4Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
Abstract. This study aims at understanding interactions between stream and aquifer in a glacierized alpine catchment. We specifically focused on a glacier forefield, for which continuous measurements of stream water electrical conductivity, discharge and depth to the water table were available over 4 consecutive years. Based on this data set, we developed a two-component mixing model in which the groundwater component was modelled using measured groundwater levels. The aquifer actively contributing to streamflow was assumed to be constituted of two linear storage units. Calibrating the model against measured total discharge yielded reliable sub-hourly estimates of discharge and insights into groundwater storage properties. Our conceptual model suggests that a near-surface aquifer with high hydraulic conductivity overlies a larger reservoir with longer response time.