Dutch unimpressed by Australian dykes
The Dutch regard Australia's flood precautions as pretty puny. There are hardly any dykes and the population of Queensland and Brisbane have to make do with some low embankments as protection.
Dutch dyke builders also regard the mere two metres that the water has to rise before the city starts to flood as useless.
"Totally unacceptable" snaps Huub Savenije, a hydraulic engineer at the University of Technology in Delft. A flood risk of once every 50 years, as Brisbane has, would be completely impossible in the Netherlands. Dutch dykes and flood barriers are so effective that the city of Rotterdam, for example, can look forward to just one major flood every ten thousand years.
On the other hand, if Rotterdam flooded the country would be bankrupt immediately, since the water would stay. The Netherlands would function as a kind of bathtub, since most of it is below sea level. Brisbane is built on a river delta, so the water will just drain away once the rains stop. In that respect the floods there are much less of a disaster than the last great Dutch flood in 1953, even though the Australian city has two million inhabitants.
Huub Savenije also concedes that you can't accuse Brisbane of having done nothing. But the measures taken differ from the Dutch situation.
Australia, Horsham : flood water in the Victorian town of Horsham on 17 January 2011: anxious residents of towns in southern Australia braced for once-in-200-year floods, as the government said the rolling flood crisis was its costliest natural disaster ever
"The Australians have an excellent warning system. They have a comprehensive measurement network which can all be monitored continuously online. There are several levels: in case of a 'minor flood' farmers have to take their cattle off the land. With a 'moderate flood' people are instructed to move all their valuables and a 'major flood' means people have to evacuate the areas threatened with flooding."
In other words, not such poor precautions after all. The population is also more accustomed to extreme weather conditions. Brisbane, for instance, is full of Queenslanders - wooden houses on poles. So the possibility of flooding is taken into account. That's also the reason there are traffic signs along many routes warning 'Road subject to flooding'.
Nevertheless, people still find it attractive to build in the low-lying areas. It becomes taboo again after each major flood but, as Huub Savenije points out, people's memories are short and the norms tend to be relaxed again after 30 years or so. Buildings and parking lots reappear and the next flood ends up causing huge amounts of damage again.
You can't compare Brisbane with, say, the conurbation in the west of the Netherlands, he adds.
"If something like this happened in the Netherlands it would be regarded as the end of the world. What's happening in Brisbane right now will cause serious economic damage, but that will be it. I don't expect there will be many casualties. There will be a few, of course, because there are always people determined to ignore the warnings. But the number will be small."
Playing it safe
Dutch norms governing flood protection are regarded internationally as exceptionally high. Professor Jur Battjes was part of the Dutch delegation that visited the disaster area after the hurricane in New Orleans. The idea was that Dutch know-how could be useful in the wake of the floods. He agrees that Dutch norms are not always desirable in the rest of the world.
"It's a difficult issue, one that's very much culturally determined. I've noticed a difference in attitude: people in the United States - and Australians seem to be comparable - have a different attitude to people in Europe. In the Netherlands we like to play it safe."
The Dutch, he explains, tend to go for expensive insurance. In other words, to spend billions protecting themselves from flooding. In other countries they're more inclined to think: "that's too bad, let's start again".
Thijs Westerbeek van Eerten