When Johann Strauss gazed upon Europe's grandest waterway 140 years ago, it inspired him to compose the Blue Danube Waltz, went on to become an unofficial anthem of the Austro-Hungarian Empire.
Today, the river that flows beneath the bridges of the Hungarian capital is anything but blue. Befouled with sewage, fertilizers, and industrial waste, the opaque, brown Danube has become a drainage canal for half a continent, so poisonous that it has devastated life in the Black Sea, which lies at the end of the 1,800-mile long river.
Last week, the Switzerland-based environmental group WWF-International (a branch of the World Wildlife Fund) named the Danube one of the world's 10 most threatened rivers, along withthe Yangtze, Nile, Ganges, and Rio Grande.
"Some of the rivers on the list are so damaged that they may really be lost, but others are in a better state and could still be saved if correct action is taken," says Christine Bratrich of WWF's Vienna-based Danube-Carpathian Programme. "The Danube still has the potential to be preserved."
More than 80 percent of the Danube's floodplains and wetlands have been lost to development and navigational projects, exterminatingthe river's sturgeon stocks and lowering water quality in the main channel. Extensive sewage and agricultural pollution – particularly in the former Communist nations of the middle and lower basin – triggered algae blooms that snuffed out much of the life in the Black Sea in the early 1990s.
Solving these problems is complicated by the fact that the Danube basin is shared by 19 countries. Cooperation on environmental issues was all but impossible during the cold war, which divided the basin in two, and little better in the 1990s, when the Yugsolav wars turned swaths of it into a battleground.
The past five years have seen considerable progress, however, as the European Union – with its strict environmental regulations – has expanded to include Slovakia, Hungary, Romania, Bulgaria, and other nations located in the middle and lower basin.
"When these countries joined the EU, they also had to adopt new environmental policies and regulations, which has had the benefit of improving the overall water quality situation in the Danube basin," says Ivan Zavadsky, director of the Danube/Black Sea Regional Program in Vienna, a joint project of the United Nations and World Bank that has pumped $70 million into cleanup projects in the region.
New sewage treatment plants have been built in recent years, while many of the most polluting factories and agricultural enterprises collapsed in the early 1990s. As a result, Mr. Zavadsky notes, concentrations of phosphorus and nitrogen – the nutrients that ravaged the Black Sea – have gone down 50 percent and 20 percent respectively since 1989.
"We're witnessing the first signs of a recovery of the Black Sea ecosystem," Zavadsky says. "But the situation remains on a knife's edge."
János Zlinszky of the Regional Environmental Center for Central and Eastern Europe is concerned that the gains could be lost if the region's economic recovery outpaces its environmental investments. "Romania and Bulgaria have just joined the EU," he says – which means they no longer face the EU's tough agricultural trade barriers. "If they decide to focus on intensive agriculture rather than the organic market, we could see great increases in fertilizer and pesticide use."
WWF's primary concern is an EU plan to improve navigation on the middle and lower Danube, an effort they say will destroy some of the last ecologically sound portions of the river. "They want to make the Danube into a 'highway to the sea' but they are not taking into account how it will affect the ecological status of the river," Ms. Bratrich says. "We shouldn't make the same mistakes in the lower Danube that we [Western European nations] made in the upper stretch."