Swiss extreme athlete Ernst Bromeis explains to Meritxell Mir what’s motivating him to become the first ever person to swim the entire 1,230-kilometres of the Rhine, from its source in the Swiss Alps to the North Sea.

It was 7am on Wednesday May 2nd when Ernst Bromeis waded into the frozen waters of Toma Lake, where the Rhine’s source lies at an altitude of 2,344 metres. Unable to swim in a surface covered with a 40-centimetre layer of ice, the endurance athlete plunged into a small pool carved in the ice for the occasion.

After this symbolic act to mark the beginning of his aquatic adventure, the 43-year-old “water activist,” as he likes to define himself, skied down to the village of Disentis, in canton Graubünden. There he began the real swim – one that will take him downstream to the six countries that straddle the Rhine as he seeks to swim the entire length of the river in just one month.

“I’m nervous,” the experienced swimmer told The Local the day before he started his journey.

‘The Blue Wonder – Rhine 2012’ is a joint project between Bromeis and Switzerland Tourism to promote the Alpine land as “a country of water” and a sustainable destination.

To characterize Bromeis’s adventure as daring would be to downplay this gruelling task. The Swiss activist will swim an average of 50 kilometres per day, a distance that will take him between five and six hours depending on the current, the mountainous nature of the terrain, and weather conditions. On the stretch between the source and Lake Constance, he’ll contend with water temperatures of between four and six degrees Celsius. Further down, as the Rhine approaches Rotterdam, it rises to 12 degrees at this time of year.

But biting temperatures won’t be his only hurdle.

The nature of the Rhine changes a lot during its course. In the first stretch, where the river crosses a dramatic canyon 20 kilometres long, he will have to be careful not to bump into the rocks and logs that dot the rapids as well as avoid multiple swirls. At Lake Constance, where there is no current, he will have to swim about 12 kilometres. For anyone wondering how he will overcome the Rhine Falls, Europe’s largest waterfall, there is no great mystery: he will briefly hop ashore before resuming his adventure at the bottom.

“I really want to make it to Rotterdam, and not die on the way,” he said.

Once in Basel, the water travels at a speed of 10 to 15 kilometres per hour, although he claims he won’t be carrying one of the floatation devices that are so popular during the summer there.

“I’m a real swimmer,” he said laughing.

Although escorted along the way by a small boat with a rescue team, Bromeis is concerned about swimming near the port of Rotterdam.

“The ships there are so big and I am so small,” he explained.

But the Swiss swimmer is no rookie when it comes to endurance swimming.

A former teacher and Olympic triathlon trainer, Bromeis has been a full-time water activist for the past four years through his project, The Blue Wonder, which he hopes will help raise awareness about water-scarcity issues.

In 2008, Bromeis crossed the 200 lakes of his home canton Graubünden, most of them in glacial temperatures. Two years later, he challenged himself again to swim across the largest lake in each of the 26 cantons, covering a total of 300 kilometres.

“My motivation comes from deep inside,” he said, adding that he feels “great passion” for environmental issues.

“Water means life in the whole world,” he said. “We, in Switzerland, are so privileged to have such a wonderful resource, but we have to be careful because the Rhine is also very fragile and its water is limited.”

So when Switzerland Tourism decided two years ago that the focus for its 2012 summer campaign would be promoting the Alpine land as a “country of water,” they realized there could be no better “water ambassador” than Bromeis, says Rafael Enzler, head of marketing at the organization.

His travels through six countries also offer an excellent opportunity for the tourism board to sell the blue wonders of a country often seen solely as a mountain destination, a circumstance Bromeis describes as “a paradox.”

According to the Swiss Federal Office of the Environment, about 6 percent of the fresh water resources in Europe originate in the Swiss Alps. With 7,000 lakes, 65,300 kilometres of rivers and streams, and 122 glaciers, Switzerland is as blue as it is green.

“There are 50 million people living along the Rhine in Europe, but a lot of them don’t even know where it starts,” said Enzler. “The river is not so nice everywhere it passes, so many people cannot imagine how beautiful it is at the source.”

But Bromeis, with his adventure, is hoping to change all that.

Follow Ernst Bromeis's progress on the Blue Wonder blog.