https://www.washingtonpost.com/science/2019/01/17/experts-warned-this-floating-garbage-collector-wouldnt-work-ocean-proved-them-right/
Experts warned this floating garbage collector wouldn’t work. The ocean
proved them right.
By Ben Guarino
January 17 at 6:00 PM
The remarkable journey of a multimillion-dollar plan to remove plastic
from the Pacific began with a teenager’s TEDx talk. In 2012, 18-year-old
Boyan Slat proposed an invention to collect garbage from the ocean’s
surface. His talk went viral. Slat dropped out of Delft University of
Technology and founded the Ocean Cleanup, a Dutch nonprofit organization
attempting to build a flotilla of sea-sweepers. By 2017, the Ocean
Cleanup had raised $31.5 million, which included contributions from
billionaire venture capitalist Peter Thiel and philanthropists Marc
Benioff and Lynne Benioff.
Rougher waters lay ahead. The organization’s first garbage collector, a
2,000-foot buoy-and-skirt invention nicknamed Wilson, broke in two. On
Dec. 29, the Ocean Cleanup discovered a 60-foot section had snapped
free. Worse, during its initial four months at sea, Wilson failed to
collect any trash in a trash-rich region known as the Great Pacific
Garbage Patch. A tugboat towed it toward Hawaii’s Hilo Bay, where the
contraption was anchored on Thursday.
Scientists unaffiliated with the project are skeptical that this system,
or future iterations, will work as intended. Kim Martini, an
oceanographer and science communicator, and Miriam Goldstein, director
of ocean policy at the Center for American Progress, independently
reviewed the Ocean Cleanup’s feasibility study in 2014 and found it wanting.
“When the feasibility study came out, the press was really excited about
this,” Martini said. “But a lot of scientists had been saying, ‘Well,
you know, this is really hard and probably not going to happen.’ ” Since
the 2014 review, the buoy-and-skirt design changed, becoming smaller and
omitting a deep-sea anchor system. But Martini and Goldstein said their
assessment remains the same: The Ocean Cleanup’s goals are laudable. Its
design is not feasible.
During a live video chat in 2014, Nicholas Mallos, an expert in marine
debris at the Ocean Conservancy, asked Slat about Martini and
Goldstein’s concerns. Slat replied that the women were not engineers.
“And that,” said Goldstein, who wrote her dissertation on the ecological
impacts of plastic in the garbage patch, “is the only response we ever got.”
Earlier this month, Clark Richards, a physical oceanographer at the
Bedford Institute of Oceanography in Nova Scotia, pointed out the
possible physics flaws in Wilson’s design. Slat, on Twitter, thanked
Richards soon after the oceanographer posted his critique. Goldstein
said “it was a bit puzzling as to why Clark got an immediate polite
response” but the two women did not, nor did Rebecca R. Helm, a
jellyfish expert at the University of North Carolina at Asheville who
also has raised concerns about the project.
Martini said she was disappointed, but not surprised, by Wilson’s recent
stint at sea. The oceanographer said she hoped the project would prove
her wrong. “The reality is that I do care about the ocean. I want things
to change,” she said. “And so do a lot of the people that work there.”
Slat, in his TEDx talk, described the modern era as the Plastic Age.
Humans have produced about 8,300 million metric tons of plastic since
its invention. Approximately 8 million metric tons of plastic waste
enters the ocean in a year, according to a 2015 estimate. “That’s
roughly equivalent to a New York City garbage truck full of plastic
being dumped into the ocean every minute of every day for an entire
year,” Mallos told The Post. By 2050, oceanic plastic will outweigh the
collective bulk of the world’s marine fish, the World Economic Forum
predicted.
Some of this plastic gets concentrated, thanks to a circular current
called a gyre, in a region known as the Great Pacific Garbage Patch.
Plastic particles, many the size of a pinkie fingernail or less, swirl
through the water there. “If you drag a fine net through the water, you
get what is, essentially, plastic confetti,” Goldstein said. “There’s
just tiny little fragments for thousands of miles.”
The Ocean Cleanup likens its invention to an artificial coastline.
Beneath the long buoy is a skirt that descends 10 feet below the
surface. The system, propelled by wind and wave energy, is supposed to
outpace the plastic particles. In theory, the skirt should corral
plastic, like a broom, into a contained area where ships can easily
scoop up the trash.
Richards was not shocked that a large, first-of-its-kind structure broke
after a few months at sea. He offered a maritime maxim: “Anything that
can go wrong will go wrong, and anything that’s not supposed to break
will,” he said. Given the harshness of the ocean environment, “we tend
to build things as small and minimal as possible.”
“Our working hypothesis is that material fatigue, caused by about 1.5
million load cycles, combined with a local stress concentration” led to
a fracture, said Jan van Ewijk, a representative for the Ocean Cleanup.
Despite the setback, the nonprofit organization aims to deploy 60 buoys
in the coming years that it says could shrink the Great Pacific Garbage
Patch by 90 percent by 2040. “We are not ending the program. Wilson will
be repaired, modified and brought back to the Great Pacific Garbage
Patch as soon as possible,” van Ewijk said.
Although Wilson was too sluggish in its first test, “most aspects of
concept have been confirmed,” including the ability to intercept
plastic, Slat tweeted on Dec. 11. “It’s just not moving fast enough
yet,” he wrote. “This is fixable.”
The Ocean Cleanup may be relying on simplified physics that do not
account for small-scale currents, Richards wrote on his blog on Jan. 6.
Zoomed way out, the Pacific gyre rotates predictably, like the swirl of
a giant toilet. But, close up, the region is a jumble of very tiny
eddies that Richards described as “squirts” and “jets.” A complex dance
of waves, wind and current plays out at the ocean’s surface, he said.
That dance may not propel the system as fast as it needs to go.
“I am skeptical, with their current design, they can make fixes — by
that I mean small or incremental things — that will change the reality
of the ocean environment that they are trying to harness,” he said. One
of the Ocean Cleanup’s senior engineers contacted Richards last weekend.
(Goldstein, when asked whether the Ocean Cleanup reached out after a
prototype device failed in 2016, laughed.)
The Ocean Cleanup also says marine life can swim beneath the device
unharmed. Goldstein, however, pointed out that organisms called neuston,
which include jellyfish and snails, live only on the ocean surface and
cannot dive. She was not concerned about a single device. But, if the
Ocean Cleanup deployed 60 giant floaters, “they would necessarily take
all the neuston out with all of their trash,” she said. “There’s really
no way around it.”
Goldstein, Martini and Mallos offered several alternatives to high-seas
garbage collectors. “There is no silver bullet, and we have to attack it
from all angles,” Goldstein said. She advocated for stopping waste
sooner — preventing trash from leaving the coasts — before devoting
resources to the plastic waste far from shore.
“Legislation is really the way to go,” Martini said, to “make people
responsible and companies responsible for the amount of plastic they’re
producing.”
Mallos recommended beach cleanups, like the International Coastal
Cleanup run by the Ocean Conservancy. These volunteer efforts have
prevented nearly 300 million pounds of trash from escaping into the
ocean, he said. “That’s an exorbitant amount of debris that did not
require us to go out to the middle of the ocean to have an impact.”
Technology can help, too, Martini said, pointing to the water wheels in
the Baltimore harbor. They may be the most popular garbage collectors on
the Eastern Seaboard. (A bug-eyed personification of one wheel, named
Mr. Trash Wheel, has 17,800 followers on Twitter.) The wheels, powered
by flowing rivers and solar energy, lift trash out of the water. Two of
the wheels have removed 999 tons of waste since 2014. If Baltimore
spends as much money operating Mr. Trash Wheel as the Ocean Cleanup
already has on Wilson, it could keep the wheel spinning for 70 years.
[I agree that we need to take multiple approaches to removing plastic
pollution which is already in our oceans, as well as reducing the
amounts continuing to be added. I am currently working on a couple of
approaches, including a technology which should be able to remove
floating plastic and other garbage from the ocean. We believe our
approach can be refined to reduce (but not eliminate) the amount of
accompanying fauna being collected with the garbage. Please contact me
off-line at darryl at restco dot ca if you want to learn more.]
