140,000 Dutch homes a flood risk in heavy downpours: report

Summer storm floods street in Asten, 1 June 2016 (Photo: @Twann0/Twitter)Summer storm floods street in Asten, 1 June 2016 (Photo: @Twann0/Twitter)

Over 140 thousand homes in the Netherlands will flood during heavy rain showers. At least 76 thousand other buildings, such as schools and shops, are also at risk of major damage due to flooding, according to research by RTL Nieuws and consultancy and engineering firm Arcadis. 

The researchers looked at the consequences of 70 millimeters of rain falling in two hours. They found that towns, villages, districts and neighborhoods throughout the country are at risk of sustaining significant damage caused by flooding. The total damages can amount to 6.8 million euros, according to conservative estimates by Arcadis.

Such local downpours happened over 70 times a year in the Netherlands over the past years, according to estimates based on radar measurements. The showers mainly fell outside urban areas, where water caused less damage. But if such a storm falls in a city or town, things can quickly go wrong. Arcadis estimates the average damage to a flooded home due to extreme rain at 30 thousand euros. And that is a conservative estimate. Arcadis did not take basements, sheds and surface water into account.

"It is extreme, but in the Netherlands we have to be prepared for it", Sabrina Helmyr, climate change expert at Arcadis, said to the broadcaster. "For example, if streets become flooded and ambulances can't get through anymore. It is good if we are aware of it." Governments need to make preparations. "Municipalities and provinces are generally already very busy with it. But we think it can be done faster. Moreover, we want to make residents aware of the danger. If we let it happen, the disaster cannot be ignored."

According to Nicolien Kroon, meteorologist at Buienradar, the Netherlands will see more heavy downpours in the future. "The earth is warming up and warm air can retain more moisture. That has to fall out again at some point." The chance of heavy downpours is greatest in the summer. "We are certainly not done for this year. Up to and including September we have to take such heavy showers into account."