A Fleet Of Screens Designed To Tame the Garbage Patch
Flush with $31.5 million in crowd-sourced funds from passionate individuals, as well as tech giants, Dutchman Boyan Slat has a plan to rid the world’s oceans of trash with a mobile drifting system. And he’s two years ahead of schedule. A design breakthrough and an infusion of cash from a campaign by the Ocean Cleanup Project, the foundation Slat heads, means testing of the first system will start in the Pacific by the end of this year. The first deployment in the Great Pacific Garbage Patch is expected during the first half of 2018.
“The plastic is accumulating,” Slat says. “It’s getting worse, fast. It stays there. It will not go away by itself. It’s persistent. And it becomes more harmful over time. We must defuse this ticking time bomb.”
Initially, the group Slat founded in 2013 said the system could be researched, tested and ready to start the cleanup in 2020. This past May, Slat cautioned that large-scale trials of the cleanup technology in the Pacific later this year are still experimental. The foundation’s June 2016 pilot project in the North Sea with a 328-foot prototype boom failed after the unit succumbed to rough seas, but the test helped the team advance to the current design, Slat says.
More than 8 million metric tons of toxin- containing plastic enters the ocean annually, scientists say. Another calculation places the global total at 5.25 trillion pieces, with a third of that concentrated in the Great Pacific Garbage Patch, the world’s largest concentration of marine debris, which circulates in the North Pacific Gyre, a Pacific current.
In total, five global garbage patches exist, including in the Indian and Atlantic oceans. Once the plastics break down into particles, fish and wildlife ingest them, and they enter the food chain. Toxins in plastics are directly linked to cancers, birth defects and immune system problems in humans.
Slat’s system, being created by a team of 65 engineers and researchers, would capture plastic pieces before they break down. In November 2014, Slat won the Champions of the Earth award from the United Nations Environment Programme. In 2016, he was named a Thiel Fellow as part of the program started in 2011 by venture capitalist and PayPal co-founder Peter Thiel to help young people turn compelling ideas into concrete results.
Now, Slat’s campaign has added computer modeling, which he says shows the new design concept cuts cleanup time in half, from 10 years to five years, for removing 50 percent of the Garbage Patch trash.
The basis of the mobile drifting system is “passive plastic capturing technology,” which uses ocean currents to catch and concentrate the plastic. Closed screens, instead of nets, help avoid bycatch. Fish, marine mammals and sea turtles can swim under and around the
solid screens, according to the team.
“Our core principle is that we work with nature and use ocean currents to our advantage,” Slat says. “Why go after the plastic if the plastic can come to you? We’re taking the idea one step further. To catch the plastic, act like the plastic.”
Rather than one massive barrier, as originally conceived, the modular cleanup system consists of a fleet of U-shaped screens that channel floating plastic in the top layer of ocean water to a central point. Rather than fixing the floating screens to the seabed at great depths, 40-foot sea anchors about 1,900 feet from the water’s surface would ensure the floating screens move slower than the plastic. Essentially, the long network of floating barriers is expected to act like an artificial coastline, and withstand changes in weather for years.
Once plastic is collected, the group sees recycling as a logical next step.
Boaters may recall Slat from the Mega Expedition. In August 2015, a flotilla of 50 vessels, some of them returning to the U. S. West Coast from the Transpacific Yacht Race finish in Hawaii, participated in Ocean Cleanup’s inaugural research effort. Ocean Cleanup offered voyagers as much as $10,000 per boat to offset costs of the 2,500-mile voyage.
Dragging small surface trawls, the fleet collected evidence that made it possible for Ocean Cleanup to measure the amount and distribution of plastic in the Great Pacific Garbage Patch, as well as create a map. The American Sailing Association partnered with Ocean Cleanup to document the undertaking in video.
While Slat participated in the Mega Expedition, making the crossing aboard a Nelson-Marek 68 Swiftsure, cruising isn’t what galvanized his attention to the problem of ocean plastic. At 16, he was drawn to the cause after seeing plastic bags while scuba diving in Greece.
Regardless of its popular appeal and a groundswell of support, Ocean Cleanup’s technology remains untried. Some scientists have questions about what they call flaws in the feasibility study. Also, no detailed plan exists for the material collected, beyond discussion posted on the group’s website.
Nancy Wallace, director of the Marine Debris Program at the National Oceanic and Atmospheric Administration, told the Associated Press that much of the garbage in the world’s oceans is found throughout the water column at depths beyond Slat’s mobile drifting system.
A piece in Deep Sea News, by oceanographer Kim Martini and marine biologist Miriam Goldstein, criticized the feasibility study’s range, from the water column depth to bycatch to the boom system. “While the feasibility study includes chapters on boom design, environmental impacts, bycatch and high seas law, they are largely reviews and do not provide a framework for how the Ocean Cleanup will address these fundamental issues,” Martini writes. “We continue to have serious reservations about the success of the project.”
Some nonprofit groups believe the money is better spent on prevention. “Oceanographers have found that over 80 percent of plastic waste in the ocean comes from land, and the amount of plastic entering the ocean is expected to increase annually,” says Hilary Kotoun, social impact director with the nonprofit ocean protection group Sailors for the Sea. “Working to stop it from entering the ocean at the source through reduction, better waste management and innovative product design is key to tackling this serious pollution problem.”
Yet support does exist from key groups, such as the nonprofit Ocean Conservancy. “Cleanup is absolutely part of the solution,” says Sandra Whitehouse, senior policy consultant. “Ocean Conservancy appreciates Boyan’s passion and interest in this issue, and the attention he’s brought to the very serious issue of marine debris.
“We encourage Boyan to work with the scientific community. Scientists have identified that focusing his technology at major river mouths/coastal environments where debris is most concentrated and where marine life is greatest would be most effective.”