Die Wasserqualität der Donau von der Bregquelle bis oberhalb Ulm
[The quality of the water in the Danube between Breg spring and Ulm]
published: Nov 1, 1969
Pollution is severe below Tuttlingen and Gutmadingen. It is worse below the former but better in other stretches than it was some ten years ago. The Danube still has the capacity to purify itself within a comparatively short distance.