Pilot project Karst Hydrogeology Hartelsgraben 2006-2008

Knowledge of the (mostly underground) drainage of a karst area is the key to understanding the cave formation and cave development of this region. While in many important karst areas of the Northern Limestone Alps a plausible model of drainage can be created today on the basis of very extensive and elaborate investigations (mostly water-economic background), this is not yet possible for the groom. Since the waters of the Gesäuseberge are not used supraregionally, but only regionally and locally, such comprehensive investigations have so far been omitted for cost reasons. In addition, the geological-morphological findings already show a special feature of karst watering: The powerful dolomite base acts practically like a sponge has a tremendous retention capacity and does not release the water in some large karst springs, but in a number of small springs. Only in extreme precipitation events or snow melts become quite high, at the dolomite/lime boundary and above spring exits, which then drain temporarily and above ground in the dolomite area and lead to the known erosive terrain forms in the dolomite karst. In the area of the Hartelsgraben, however, the dolomite is already so deep that the entire trench only intersects the Dachsteinkalk (Fig. 3) and the Hartelsgraben has a special hydrological position for at least one part of the southern Gesäuse Mountains.