The Ocean Cleanup has launched its plastic extraction system from San Francisco Bay ahead of final testing before it travels to the Great Pacific Garbage Patch to begin cleanup operations after half a decade of development.

The Dutch marine litter project, founded by Boyan Slat in 2013, aims to tackle marine plastic pollution, particularly in the Pacific. Ocean plastic pollution is one of the major environmental challenges of our age, with experts estimating that 12.2 million tonnes of plastic enter the ocean every year, with 140,000 tonnes concentrated in the Great Pacific Garbage Patch.

The Ocean Cleanup barriers being pulled out to sea past the Golden Gate Bridge, San Francisco. Image: The Ocean Cleanup

The system pioneered by The Ocean Cleanup is based on deploying barriers to act as an artificial coastline and passively catch and collect ocean debris. The ‘V’-shaped barrier comprises buoyancy elements with weighted ‘skirts’ – thin, impermeable and flexible sheets that direct the plastics – hanging to a depth of two to three metres. These will concentrate the plastic towards a central platform where ships will pick up the plastic for recycling.

Earlier feasibility studies have indicated that 80 per cent of the plastic that encounters the barriers will be captured, while most of the ocean current will pass underneath the structure, carrying away sea life and preventing by-catch.

After an influx of funding last year, The Ocean Cleanup has suggested that the project’s system will allow the cleanup of half of the Great Pacific Garbage Patch in just five years.

After 273 scale model tests, testing of six at-sea prototypes, a comprehensive mapping of the Great Pacific Garbage Patch with 30 vessels and an airplane, and several technology iterations, The Ocean Cleanup has finally launched its extraction device to begin cleaning up the ocean.

The foundation launched its mobile drifting system (System 001) on 8 September, and in the next few days it will arrive at a test location in the Pacific, 250-350 nautical miles offshore, where it will be assembled in its operational V-shape configuration for the first time, before being tested and trialed over the course of two weeks.

If all goes to plan, System 001 will then be towed the remaining 1,000 nautical miles to the Great Pacific Garbage Patch, which could take up to three weeks. Once System 001 has reached the patch, it will once again be deployed in its operational V-shape and the cleanup operation will commence.

Commenting on the launch, founder Boyan Slat said: “I am incredibly grateful for the tremendous amount of support we have received over the past few years from people around the world, that has allowed us to develop, test, and launch a system with the potential to begin to mitigate an this ecological disaster. This makes me confident that, if we manage to make the technology work, the cleanup will happen.”

Long time coming

The project has seen a long journey before appearing to finally come to fruition, as Slat was just 18 years old when he came up with the idea of The Ocean Cleanup. He had a vision to create long, floating barriers that would remain stationary in water, using the ocean’s current to collect plastics that gather in the Pacific.

Many trials and testing have been carried out on the technology, with a fleet of 30 vessels dispatched to the Great Pacific Garbage Patch in August 2015 in an attempt to measure debris and quantify the true level of plastic in the area. The findings from this expedition were supplemented by findings from an aerial expedition in October 2016.

In June 2016, a 100 metre-long prototype of the oceanic barrier was deployed in the North Sea, 23 kilometres off the coast of the Netherlands, to test the resilience of the floating barriers to extreme weather conditions.

The project has attracted much publicity and international attention and acquired $21.7 million (£16.8 million) between November 2016 and May 2017, which allowed development to accelerate.

However, while receiving great support and acclaim for its system design, experts have expressed doubts over The Ocean Cleanup’s assertion that the majority of marine plastics collects on the surface of the ocean because ‘larger sized plastic pollution, which by mass represents most of the plastic in the ocean, is more buoyant and stays even closer to the sea surface’.

Environmental consultants Eunomia Research & Consulting say that barely one per cent of marine plastics concentrate on the ocean surface, with 94 per cent of plastic that enters the ocean ending up on the sea floor. The consultancy advocate fighting plastic pollution on the beaches, before it enters the oceans.

You can find out more about The Ocean Cleanup on the project’s website.