A multimillion-dollar floating boom designed to corral plastic debris littering the Pacific Ocean deployed from San Francisco Bay on Saturday as part of a larger high-stakes and ambitious undertaking.
The 2,000-foot-long unmanned structure was the product of about $20 million in funding from the Ocean Cleanup, a nonprofit that aims to trap up to 150,000 pounds of plastic during the boom’s first year at sea. Within five years, with the creation of dozens more booms, the organization hopes to clean half of the Great Pacific Garbage Patch.
The patch, a gyre of trash between California and Hawaii, comprises an estimated 1.8 trillion pieces of scattered detritus, including at least 87,000 tons of plastic.
Over the next several days, the boom will be towed to a site where it will undergo two weeks of testing. If everything goes as planned, the boom will then be brought to the garbage patch, nearly 1,400 miles offshore, where it is expected to arrive by mid-October, said Boyan Slat, 24, the Dutch inventor and entrepreneur who founded Ocean Cleanup.
The cleanup system is supposed to work like this: After the boom detaches from the towing vessel, the current is expected to pull it into the shape of a “U.” As it drifts along, propelled by the wind and waves, it should trap plastic “like Pac-Man,” the foundation said on its website. The captured plastic would then be transported back to land, sorted and recycled.
The boom has an impenetrable skirt that hangs nearly 10 feet below to catch smaller pieces of plastic. The nonprofit said marine life would be able to pass underneath.
But the ocean can be unpredictable, and simulation models are no guarantee of future performance.
“There’s worry that you can’t remove the plastic without removing marine life at the same time,” said George Leonard, chief scientist at the Ocean Conservancy. “We know from the fishing industry if you put any sort of structure in the open ocean, it acts as a fish-aggregating device.”
Small fish, drawn to a new structure, can attract bigger fish, he added, creating an “entire ecological community.”
It is unclear how well the boom would fare on the open ocean, where it faces high winds, corrosive salt water and other environmental challenges. And then there’s the question of whether it is possible to clean half of the garbage patch in just five years.
“I think the big challenge here is not the long-term goal but the short-term goal,” Mr. Leonard said on Saturday. “Can it remove plastic at all?”
Mr. Slat, the chief executive of Ocean Cleanup, shared the same worry in a video posted on Facebook.
“And to me this is where I think my largest anxiety lies at this point in time,” he said of the system’s ability to collect and retain plastic. “First of all, it’s something that we haven’t really been able to test very well.”
But on Saturday morning, Mr. Slat was decidedly optimistic.
“I’ve definitely never been so confident about the chance of success as I am today,” he said.
Since the start of Ocean Cleanup in 2013, donors have contributed nearly $35 million, Mr. Slat said. Much of that money paid for the boom and helped underwrite research like a study published in the journal Scientific Reports, which quantified the full extent of the garbage patch. Future booms are estimated to cost about $5.8 million each.
Major sponsors include Marc Benioff, the chief executive of Salesforce.com, and Peter Thiel, the co-founder of PayPal.
Skeptics questioned whether this was the most economically efficient way to address the problem.
“I fully agree that this is not the full solution to plastic pollution,” Mr. Slat said.
While it’s necessary to prevent more plastic from entering the ocean, what is there already isn’t going to go away by itself, he added.
“We have to clean it up at some point in time and, actually, I would say the sooner the better,” he said.