Giant North Sea dam to combat problem of ocean plastic?

A little while ago, I wrote a number of posts on the growing problem of plastic waste in our oceans and what is being done about it, including the development of large, plastic-collecting, floating barriers by the organisation, Ocean CleanUp. Now, the organisation's founder, Boyan Slat, whose technology has already been trialled in Dutch lakes and in Japan, is installing a revolutionary 328ft giant 'dam' in the North Sea next year. The barrier, which will be installed some 14 miles off the coast of the Netherlands, will trap plastic waste floating in the sea using giant buffers while allowing fish and other sea creatures to safely pass through underneath.

One of the large floating barriers similar to the one which will be installed in the North Sea next year (Source: http://i.dailymail.co.uk/i/pix/2015/06/05/12/29600FF200000578-0-image-a-15_1433503748631.jpg)

This will be the first time that the technology will be tested in open waters and will provide an opportunity to measure the effects of waves and currents on the barrier using cameras and sensors. If successful, Ocean CleanUp hope to install other floating barriers around the world, with plans for a 100km long v-shaped one in the 'Great Pacific Garbage Patch' where large volumes of plastic rubbish collect. The company estimate that once installed, the barrier could collect around 42% of the plastic in this area over 10 years, representing a phenomenal 70, 320, 000kg of plastic!

The video below shows what the organisation do:

However, not everyone is convinced of the project's feasibility with many condemning the giant barriers as unsupported by scientific research and as a quick-fix to a problem of a colossal scale. It is argued by some that the barriers will quickly become colonised by sea life such as barnacles, fish and sea birds which when coupled with salt from the ocean, could spell disaster for the functionality of the equipment. Another issue is that the tiny organism, plankton, which have no control over their movements, would essentially be caught up in the currents directing the removed plastic into the recycling containers...with plankton so vital to the food chain this could be a huge problem with the barriers and Slat himself admits that more research is needed on this.

There are also issues with the economics of the project as the plastic, once collected, will need to be sorted into its various types and with many of the plastic pieces on a very small scale, analysis will be costly and time consuming. Moreover, there are arguments that the barriers will not collect anywhere close to the volume suggested by the organisation as their figures are based on the assumption that most plastic is floating on the ocean's surface which is simply not the case. It has been shown that most plastic is suspended at around 100-150m in the water column meaning it would escape the barrier's claws... if this is true then the company's estimates of the timescale involved in cleaning up ocean plastic becomes vastly skewed.

For more criticism of the project see here and for Boyan Slat's response see here (all 530 pages of it...!)

At first glance, the concept of giant floating barriers to rid our oceans of plastic seems obvious...and maybe that's the problem: it's too obvious. I can't help but feel that it's going to take a lot more than two dozen or so 100km long barriers to combat the problem of ocean waste. These are merely a speck in the 315 million square kilometres of ocean...