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Heat Wave is Drying Up Europe's Water Resources

Kate Hairsine (sac)August 2, 2006

The record temperatures in July have had a dramatic effect on Europe's water resources. Many lakes and rivers are at record lows, aggravating problems already caused by bad water management.

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In Freiburg, you can walk through the Dreisam river bed these days

The heat wave that has gripped Europe this summer has been breaking records across the continent. In Germany, dramatically high temperatures made this July the second hottest since 1901. A 1911 record for the highest July temperature in Britain was broken when a village in Surrey hit 36.5 degrees Celsius (97.7 degrees Fahrenheit). And the Dutch meteorological institute said this July was the hottest month in the Netherlands since temperatures were first measured in 1706.

Even though it has cooled down somewhat in the past few days, last month was still three-and-a-half degrees warmer than average, said Gerhard Müller-Westermaier, an expert in climate monitoring at Germany's National Meteorology Service. He said that the heat wave is part of global warming.

"It fits the picture and it will continue to get warmer," Müller-Westermaier said. "We have had a warming of about 0.8 degrees since the beginning of the 20th century and the forecast says that in the next 100 years, we may have temperatures 1.5 to 5.5 degrees warmer. A summer like this one will become a normal summer."

Drought hit agricultural sector hard

Despite the many summer storms that swept across Germany, the country had less than 70 percent of the average July rainfall. This had a severe impact on the agricultural industry. In the eastern German state of Brandenburg, for example, farmers said their wheat yield was down some 40 to 50 percent.

Traktor auf Stoppelfeld
German farmers feel the heatImage: AP

According to Müller-Westermaier, more heat required more precipitation. But he said rainfall trends due to global warming have become more difficult to predict.

"The models are not very good, but what they say up to now at least for central Europe is that especially in winter we will have more precipitation," Müller-Westermaier said. "In summer, there will be less precipitation. This is, of course, not a good forecast, so perhaps we will have to change our agricultural production in the future."

EU needs to wake up to water problems

The situation is even worse for farmers in the Mediterranean countries of France, Italy and Spain. In the last year, reservoir levels in Spain have dropped to nearly half of their capacity, which is a clear indicator of drought.

Climate change has exacerbated the problems caused by bad water management. Martin Geiger, the head of the Freshwater Program at environmental group WWF, said that in countries like Spain, more than 70 percent of water resources are used in agriculture -- and much of this is wasted. He said the European Union needed to wake up to how precious a resource water is.

Symbolbild Wasser Wassertropfen p178
Water has become an extremely precious resourceImage: bmu

"If the EU would link water savings to the subsidies they provide, this would impact the current water use because there are efficiently gains of up to 30 to 40 percent you can reach with modern technology, and only a few areas currently use those modern technologies," Geiger said.

Geiger said that unless CO2 emissions are cut drastically soon, drought and desertification will become commonplace in Europe. He said that some water also needed to be given back to nature.

"WWF is calling for environmental flows, which mean that you have a minimum amount for nature conserved," Geiger said. "And not like in Spain, where you use it first for agriculture and for tourism and then the households get something, and, 'Oh, we forgot about nature.' Rather than leaving nature in last place, they should consider it in an integrated way, and include nature."

Heat is killing fish

The extreme warm weather has caused many of Germany's rivers and lakes to turn into stagnant pools, with very little oxygen in the water. Algae and other pollutants make this situation even worse.

Tote Fische im ausgetrockneten Flußbett, Hitzewelle
Dead fish in the completely dry Schwarze Elster riverbed in BrandenburgImage: AP

Hundreds of dead fish have already been found in canals and lakes in Berlin, and thousands of eels have died in wetlands along the Rhine river near Düsseldorf. The situation has become critical for the Neckar river, one of the Rhine's major tributaries in southern Germany. The water temperature has risen to nearly 28 degrees here, and the oxygen levels are seriously low.

"We have to watch the river extremely carefully," said Uwe Matthias from Baden Württemberg's Environment, Measurement and Conservation Office. "We have numerous recording stations which measure temperature, oxygen levels and conduction, and we are checking these levels practically every hour."

But if it does reach a critical stage, there are methods to get oxygen back into rivers, he said.

"You can let more water tumble over the dams, for example, which oxygenates the water throughout the churning action," Matthias said. "Also, some sewage plants have facilities to agitate or aerate water which flows back into rivers, which increases the oxygen levels."

Of course, healthier waterways aren't just better for fish and other marine life. Humans benefit as well. There's nothing quite like taking a plunge into a clear cool lake on a hot summer's day.