By Jerri-Lynn Scofield, who has worked as a securities lawyer and a derivatives trader. She is currently writing a book about textile artisans.
The first Ocean Cleanup Array is scheduled to launch from San Francisco Bay tomorrow.
Target: The Great Pacific Garbage Patch (GPGP), a major plastic accumulation zone three times the size of France, located in subtropical waters between California and Hawaii.
I’ve written about the GPGP before, in Plastic Watch: Great Pacific Garbage Patch Grows, which discussed a scientific paper Evidence that the Great Pacific Garbage Patch is rapidly accumulating plastic that documented how this pile of plastic is growing at a rate far greater than previously predicted. The paper’s estimate of the size of the GPGP is 79,000 tons, a figure four to sixteen times higher than previous estimates.
The Ocean Cleanup Initiative
The Ocean Cleanup Array is the brainchild of Boyan Slat, who as a 19-year old engineering student, invented a device in 2013 to clean up garbage patches, as reported by Treehugger in Teen invents device to clean giant ocean garbage patches. The Ocean Cleanup Foundation was formed to take Slat’s idea from concept to reality.
The array that will be launched tomorrow arrives two years ahead of schedule and is 600 meters long. It can collect about five tons of plastic per month, according to Forbes in The Ocean Cleanup Is Starting, Aims To Cut Garbage Patch By 90% By 2040.
Slat told ABC News San Francisco what sparked his idea in First of its kind ocean clean-up system to launch from San Francisco Bay on Saturday:
“If you look at the coastline, that’s actually a very effective way of collecting plastic,” he said. “So that’s why we said, ‘Why don’t we build our own coastline?'”
The Ocean Cleanup website describes further how the system works:
The system consists of a 600-meter-long floater that sits at the surface of the water and a tapered 3-meter-deep skirt attached below. The floater provides buoyancy to the system and prevents plastic from flowing over it, while the skirt stops debris from escaping underneath.
Once surrounded by the array, the plastic is accumulated, extracted, and eventually, returned to land where it will be sorted for recycling.
According to Forbes:
“We try and explain it sometimes like a leaf blower,” [The Ocean Cleanup’s chief operations officer Lonneke] Holierhoek said. In this case, the plastic is scattered like leaves, even in the garbage patch. “Having to pick up these pieces one-by-one would be very time-consuming,” she said. But corraling plastic with the cleanup system allows it to be collected more effectively and efficiently.
This two minute video provides a short explanation of how the system works.
Will This Work on a Wider Scale, Out on the Pacific High Seas?
Nothing like this system has been tried before, so it’s unclear how successful the array will be once deployed.
In this short video, which I discovered via this Treehugger article– The Ocean Cleanup is about to launch. Here’s what it faces.–Slat discusses some of the challenges the system must confront.
There are three main risks. First, is the actual performance of the Clean Up system in the rough conditions of the Pacific.
Second, is the interaction between the plastic and the clean-up system: whether the plastic can be collected, and whether it can be retained. Slat confesses this is where his largest anxiety lies, partly because it has not been possible to test very well. As Treehugger notes:
[The Ocean Cleanup’s] in-house testing has suggested they can collect items down to a millimeter in size, but that’s easier said than done when you are thousands of miles out in the ocean, and when you then have to clean and process them for recycling and/or disposal back on land.
Jerri-Lynn here: As I discussed in my previous post cited above, about half of the material in the GPGP is discarded fishing nets, and those combined with other fishing gear comprise most of the debris in the GPGP. In fact, only 8% of the content of the GPGP is microplastics.
According to The Ocean Cleanup website:
Our models indicate that a full-scale system roll-out could clean up 50% of the Great Pacific Garbage Patch in 5 years.
Research shows the majority of plastic by mass is currently in the larger debris. By removing the plastic while most of it is still large, we prevent it from breaking down into dangerous microplastics.
The third risk is the survivability of the system. The ocean is a very destructive environment, with hazards that include waves and high winds. In addition, marine animals and other creatures might damage the system, as could the corrosive effects of salt water.
These concerns are part of the reason why the system will undergo further testing, as the array moves toward the GPGP, and why, according to Treehugger, “the team has chosen to roll the project out on a modular basis, sending out a single array, learning from how it performs, and then using those lessons to improve and launch many more arrays to follow.”
If the system works as projected, The Ocean Cleanup plans to have an improved fleet of 60 more units in operation in about eighteen months.
The task of ridding the oceans of plastic is a massive one and The Ocean Cleanup initiative is itself not a complete solution. For starters, the GPGP is only one of five similar garbage patches.
The system targets larger pieces of plastic, not microplastics– but can perhaps if widely deployed reduce the future magnitude of the problems those pose by collecting larger pieces of plastic before they break down and become microplastics. But what about all the microplastics that are already fouling water supplies, and entering the food chain?
Cleanup alone won’t solve the plastic waste crisis, and there’s a risk that a seeming technofix may prevent more urgent attention to curtailing the use of plastic– particularly for single use applications– and preventing what’s produced from ending up in the ocean in the first place. I’ve written several posts about this topic, and alas, despair at the prospects for effective action anytime soon on reducing the amount of plastic created, and recycling or disposing what’s created properly (see US, Japan Reject G-7 Ocean Plastics Charter; Planet or Plastic; Plastics Pollution Policies– “Bold” or Pathetic?; Plastics Sicken Coral Reefs; EU Makes Limited Move on Plastics: Too Little, Too Late?; Fracking Boom Further Spurs Plastics Crisis; and Plastic Free July: What YOU Can Do to Reduce Plastics Waste).
Nonetheless, I can only hope The Ocean Cleanup effort succeeds, and the system is then more widely– and quickly– deployed, to clean up other plastic garbage patches.