The Landeswasserversorgung (state water supply) provides drinking water for about three million people in southern Germany. Therefore, the required water is extracted from the Danube, the Buchbrunnen Spring at Dischingen as well as from the gravel aquifer in the Donauried. One of the largest groundwater protection areas in Germany (> 500 km²) was established for the wells in the Donauried, which extends over a large area of the eastern Swabian Alb.
For a better characterization of the catchment area, several combined tracer tests with injections in swallow holes, dolines and piezometers are carried out within the framework of this project. The objectives of these tests are to confirm the catchment areas of the different wells and to identify flow velocities, pathways as well as problem areas in terms of high nitrate concentrations. It is of special importance to characterize the transition of the water from the Jurassic karst aquifer into the quaternary gravel aquifer at the Donauried.