Amsterdam now has the world’s first rubbish barrier made entirely from bubbles. The idea is to catch waste in the city’s canals before it reaches the North Sea.
Launched by a Dutch start-up and the Amsterdam municipality, the Great Bubble Barrier is a simple device that channels rubbish — including small pieces of plastic — to the side of the Westerdok Canal, where it can be collected. Tests have shown that it can redirect more than 80 per cent of rubbish.
“More than two-thirds of plastics in the ocean comes out of rivers and canals — so if you have to intercept it, why not do it in the rivers?” says Philip Ehrhorn, co-inventor of the technology. “You can’t put a physical barrier in a canal: it has to be open for wildlife and recreation.”
The hope is that the innovation will help to address the crisis of plastic waste in the oceans. Estimates suggest as much as eight million tonnes of plastic end up in the world’s seas each year — the equivalent of a truckload of plastic rubbish every minute.
The bubble barrier is a long, perforated tube that runs diagonally for 60 metres across the bottom of the canal. Compressed air is pumped through the tube and rises upwards. The natural water current helps to push waste to one side of the canal. The plastic waste is then trapped in a small rubbish platform on the side of the Westerdokskade, at the end of Amsterdam’s historic canal belt. From there, it can be collected.
A jacuzzi for plastics
Ehrhorn is a German naval architect and environmental engineer. He got the inspiration for the bubble barrier from a water treatment plant he saw while studying in Australia in 2015. “At one stage, they aerate the water and, on a big surface, put air bubbles like a big jacuzzi,” he says. “The small plastic pieces that people throw in the toilet all collected in one corner and that was the kind of spark for me: if you can guide plastic to the side, can’t you do it in a more directed way and on purpose in a river?”
Three Dutch sailors and friends — Anne Marieke Eveleens, Francis Zoet and Saskia Studer — were discussing the rubbish problem over a beer in Amsterdam one evening, around the same time as Ehrhorn was in Australia. They came up with the idea of a curtain of bubbles that sifts out waste but allows fish and boats to pass through. The two teams came together to work on the idea. They had the help of a €500,000 Postcode Lottery Green Challenge award and other prizes. The first operational barrier in Amsterdam, which will run 24 hours a day for three years, will function in addition to dredging operations, which currently collect 42,000 kilograms of large plastics from the Dutch capital’s waterways each year. Bubble barrier waste will be collected and then analysed by plastics action group Schone Rivieren (“Clean Rivers”).Hope for a waterlogged country Marieke van Doorninck, the deputy mayor of Amsterdam, hopes it will be a success. “Amsterdam’s canals have enormous appeal,” she says. “But when you think of them, you don’t think about plastic bottles and bags in the water. The bubble barrier will mean fewer plastics reach the ocean and is a step towards better regulation of our ecosystem, to the benefit of man, beast and environment.”
In the small, waterlogged country, this kind of innovation is welcome. Bianca Nijhof, managing director of the Netherlands Water Partnership, who organizes the Amsterdam International Water Week conference, says: “The Dutch live with the water and don’t fight against it: 50 per cent of the country is below sea level. More than half is prone to flooding, and in 2018, we had severe drought,” she adds. “This special relationship with water combined with an entrepreneurial mindset mean that innovation is at our core. The bubble barrier is one solution for clean water for all.”
© Guardian News & Media 2019