This article traces the course of the Elbe River from Czechoslovakia through the German Democratic Republic (GDR) into the Federal Republic, where it flows into the North Sea. As the GDR's main water artery, the Elbe's border crossings became a site of security concern for the GDR. Traversing the GDR's border with fellow communist state Czechoslovakia as well as its rival West German state, the river linked the GDR to a larger ecological system as well as transnational sociopolitical dynamics. These connections illuminated the GDR's crucial position in central Europe and beyond. Yet the Elbe also presented challenges for the GDR in terms of controlling information, people, and pollution that streamed into—and out of—the country. The river thus was a precious and contested resource that revealed the communist dictatorship's limited ability to control nature, humans, or interactions between the two. Ultimately, the Elbe's border crossings were a site of transnational and global connection that called into question the GDR's domestic legitimacy and international standing.

The sudden, large-scale cessation of industrial and agricultural practices following the collapse of the communist regimes in the former Czechoslovakia and East Germany, coupled with a set of programmes aimed at reducing industrial and municipal pollutant loads, provided an unique opportunity to observe changes in a severely polluted river, the Elbe. Several sets of data for the post-communist Elbe reflect water quality and ecological health, including surface water pollutants, accumulation in mussels and several species of fish, and diversity of fish species. The ecological health of the Elbe has indeed benefited, and greatly, from post-communist change. The loads of most pollutants in the Elbe surface water have declined significantly over the last decade. Contaminant loading in fish tissue is also declining. Finally, the diversity of fish species in the Elbe is increasing, with a majority of the returning species being native fishes, characteristic of the pre-World War Two Elbe. Nonetheless, several pollutants remain a concern, including nitrate, suspended sediments, mercury, cadmium, hexachlorobenzene, two DDT metabolites, and three HCH isomers. The reasons for these problems include relicts from the communist era and current activities in the Elbe watershed. Further, the invasion of the river by exotic species, while not yet a concern, does remain a threat.