Kauner valley

The study area is located at the end of the Kauner valley in Tyrol. It includes the 62.54 km² catchment area of the Fagge creek with the Gepatschferner and Weißseeferner glaciers, down to the inflow Gepatsch reservoir lake. 39% of the area is glaciated. The area has a large topographic relief (1765 m a.m.s.l. at the lowest point, where the Fagge enters the lake, and 3510 m at the highest peak, the Weißseespitze). The valley is characterised by ample debris supply (moraines, talus and gravel deposits). These are (re)mobilised by various geomorphic processes that sometimes reach the channel of the Fagge creek. As a result, the Fagge transports large amounts of sediments.

The Gepatschferner has retreated by c. 2500 m since the year 1850, leaving large lateral moraines (left half of the image) that today document the past extent of the glacier. Since deglaciation, they have been dissected by different geomorphic processes that deliver sediments to the Fagge creek (Photo: Betz, 10.07.2015).

Some of the transported sediment material is deposited in various storage landforms (e.g., debris cones). Large amounts also reach the Gepatsch Reservoir. Rough estimates suggest that about 12,400 m³ of bedload is deposited annually in the reservoir. By lowering the lake level by an average of 40 m before the onset of snowmelt, the delta fill of the Faggenbach is accessible for surveying. This allows the annual sedimentation in the lake to be measured at high resolution.

In addition to the favourable natural conditions for our research project, the area is also well developed in terms of infrastructure. An asphalt road reaches up to 2750 m a.s.l., making the area accessible even with heavy equipment. In addition, the operator of the reservoir collects climate data (temperature, precipitation and snow depth) in the entire area, which can be used by project scientists. Several volumes of aerial photographs dating back to 1953/54 are available for the detection and quantification of surface and landcover changes.