It was a photograph that attracted international attention: In September 1988, a man in a wetsuit jumped from a police boat into the Rhine River close to the city of Mainz in western Germany and crawled to the shore for a few minutes.

The man in the photograph was prominent Christian Democrat (CDU) politician Klaus Töpfer. He was 50 years old at the time and had been Federal Environment Minister for about 18 months. By his own admission, he wanted to show that Germany's most important river was clean enough to swim in again after it was contaminated with chemicals which killed off massive numbers of fish.

Decades later, he said the stunt wasn't just proof that the water quality had been restored — it was a wager, too. During the 1987 state election campaign, the Social Democrat (SPD) opposing candidate had predicted that Töpfer, then environment minister in the state of Rhineland-Palatinate, would soon join the German federal government and that he should no longer be elected.

Töpfer responded with his daring wager. In 1987, his election campaign was spectacular and made the television news. Today, in the age of social media, it would just be one of many audacious publicity stunts. But after these pictures, everyone knew who Töpfer was and what he stood for: water quality and environmental protection.

Töpfer's office confirmed on June 11 that the former environment minister had died on June 8 after a fall........

© Deutsche Welle