Groundwater in alpine karst systems – hydrogeological investigations in the Wetterstein Mountains, German Alps

Summary

Alpine groundwater resources are important for drinking water supply of major cities, and large regions benefit from the abundance of water. Due to poor accessibility, alpine aquifers are still little investigated. Therefore, hydrogeological research is conducted in the Wetterstein Mountains, a prominent mountain massif in the Bavarian Alps, including Germany’s highest summit, the Zugspitze (2962 m). The mountains are built up of a thick limestone formation. Numerous karst springs discharge from the steep mountain sloped and in deep gorges.

In summer 2011 and 2012, two combined tracer tests with altogether six injections were conducted. Fluorescent dyes were injected with seeping melt water directly into the limestone, and breakthrough curves were observed at several karst springs. It was possible to delineate catchment areas of springs and to characterise the high variability of underground drainage and flow velocities. The combination with natural tracers (e.g. hydrochemical parameters, isotopes) allows establishing a hydrogeological model.

 

Abbildung Höllentalkar Abbildung Grieskar

Left image: View from mount Alpspitze to the summit of Zugspitze, including Höllental cirque and the remaining glacier. Right image: Injection of Uranine, 16th July 2011, at Grieskar cirque.