Water resources in the Lake Geneva catchment, canton Vaud, and Western Switzerland

Switzerland is often considered to be “water castle” of Europe some of the most important Central European rivers have their sources in the Alps. The upper reaches of many Swiss rivers are hence characterized by glacier-dominated high Alpine catchments with sparse vegetation and thin soil covers. With increasing global warming though the proportions of glacial melt waters as well as waters from permafrost regions can make up ever-larger proportions of the surface runoff. Much of this runoff is also being exploited for hydroelectric power, further modifying the natural runoff. In addition, the vegetation and soil cover increases downstream in parallel with the agricultural exploitation, the population density, industry and number of waste-water treatment plants.
As the largest freshwater reservoir within Europe, Lake Geneva, but also most of the rivers within its catchment exemplify several key challenges for a sustainable freshwater management within Switzerland and, of course beyond: anthropogenic macro- as well as new micro-pollutants. For many of these pollutants little is known about the transport and fate within rivers and lakes and finally also within the exploited ground waters.
Both the natural and anthropogenic fluxes of water, but also the organic as well as inorganic fluxes can be traced through the atmospheric, geologic, biologic and anthropogenic cycles through the integrated use of geochemical and isotopic measurements of water and its particulate and dissolved components (hydrogen, carbon, oxygen, nitrogen, sulfur, etc.). This allows for a much-improved interpretation on the relative proportions and dynamics of such fluxes across the heterogeneous geologic catchments with variable soil covers and thickness’ as well as natural versus agricultural land use within the “water castle”.
 

Leman Lake

 

Participants: Nathalie Chèvre, Laurent Decrouy, Torsten Vennemann
Masters students: Quentin Piller, Monica Bulgheroni, Gelare Moradi

 

Typical recent publications
Halder J., Decrouy L. & Vennemann T.W. (2013). Mixing of Rhône River water in Lake Geneva (Switzerland–France) inferred from stable hydrogen and oxygen isotope profiles. Journal of Hydrology, V. 477, p. 152-164.
Decrouy L., Vennemann, T. W., and Ariztegui, D. (2012). Mg/Ca and Sr/Ca ratios of ostracod valves from living species of Lake Geneva. Chemical Geology, V. 314-317, p. 45-56.
Decrouy L., Vennemann T.W. & Ariztegui D. (2012). Sediment penetration depths of epi- and infaunal ostracods from Lake Geneva (Switzerland). Hydrobiologia, 688: 5-23.
Finger D., Hugentobler A., Huss M., Voinesco A., Wernli H., Fischer D., Weber E., Jeannin P.Y., Kauzlaric M., Wirz A., Vennemann T., Hüsler F., Schädler B., Weingartner R. (2013). Identification of glacial meltwater runoff in a karstic environment and its implication for present and future water availability, Hydrol. Earth Syst. Sci, V. 17, 3261-3277.
Vennemann, T., Fontana, D., and Paychere, S., 2009. Carbon isotope composition of dissolved inorganic carbon as a tracer of geo-, bio- and anthropogenic sources of carbon: examples from Swiss rivers and lakes. Abstract presented at the 19th annual Goldschmidt Conference in Davos, Switzerland, June 21-26, 2009. Geochimica et Cosmochimica Acta, V. 73, Issue 13 Supplement 1, p. 15, 2009.
Vennemann, T., Fontana, D., Paychere, S., Ambadiang, P., Piffarerio, R., and Favre, L., 2009. Dissolved inorganic carbon and its stable isotope composition as a tracer of geo-, bio-, and anthropogenic sources of carbon. Abstract presented at the 7th annual Swiss Geoscience Meeting in Neuchâtel, Switzerland, 20-21 November, SGM09 Abstract volume, Abstract 1.40, 2009.