Summary

The Blautopf (Blue Pot) spring at the southern border of Swabian Alb is among the largest and most beautiful karst springs in Germany. Up until a few years ago, the legendary Blue Cave System was only accessible for divers. Only since 2010, a drilled shaft allows an easier access. KIT hydrogeologists were among the first scientists who were allowed to conduct research in this cave.

In April 2012, a multi-tracer test was conducted inside the Blue Cave System and a nearby other cave system. Two different fluorescent dyes were injected directly into the cave streams, and several sites in the cave system were monitored for the tracer breakthrough. The tracer test made it possible to identify flow paths and hydraulic connections, quantify flow velocities, and to obtain relevant parameters of contaminant transport, such as dispersion and dilution.

Injection of a red fluorescent dye into the cave stream in the remotest part of the Blue Cave System, by Nico Goldscheider and a team of cavers (left picture). Installation of a fluorimeter in the cave stream of the Blue Cave by Ute Bellmann and a team of cavers (right picture) (Photographs: Andreas Kücha).