Hundreds of miles between the coasts California and Hawaii is what’s known as the Great Pacific Garbage Patch — an accumulation of plastic expanding nearly a million square miles or roughly twice the size of Texas. 
The plastic, which ranges from massive fishing nets weighing more than a ton to tiny fragments often just millimeters in size, collected for decades due to a gyre, or whirlpool of currents, that focused ocean pollution from disparate areas into one localized spot (it’s not like a floating landfill, instead the plastic is suspended throughout the water column). The patch, which was discovered in 1997, has since grown to be the largest aggregation of plastic across the world’s oceans. 
In 2013, Boyan Slat, an 18-year-old entrepreneur, set out to eliminate that patch. He founded The Ocean Cleanup, a nonprofit with the goal of eliminating ocean plastic, and crowdfunded nearly $2.2 million. 

Slat’s team built an enormous curved device with the purpose of passively gathering trash inside the garbage patch. The 2,000-foot C-shape plastic pipe is connected to a screen that spans 10 feet below the water’s surface. 
On Wednesday, following multiple setbacks, the Ocean Cleanup announced a major breakthrough: The most recent iteration of the device successfully collected and stored plastic. 
This version incorporates a parachute, which serves as an anchor. The parachute slows down the vessel so that it moves just slightly slower than the ocean’s current. That allows for faster-moving plastic to accumulate in the screen. A floatline keeps the system buoyant, and due to its slow speed, sea life are able to swim below the barrier. Large fishing nets, plastic objects, like car tires and plastic bins, along with microplastics all accumulated in the device, which is called the System 001/B.

A bird’s-eye view of The Ocean Cleanup’s device.

But creating a successful device wasn’t easy, and early versions had critical flaws. At one point, a 60-foot section broke off, and the entire device had to be brought back to shore. In another version, the collected trash would spill back into the ocean.  
“After beginning this journey seven years ago, this first year of testing in the unforgivable environment of the high seas strongly indicates that our vision is attainable and that the beginning of our mission to rid the ocean of plastic garbage, which has accumulated for decades, is within our sights,” Boyan Slat said in a press release. 
As the device catches plastic, The Ocean Cleanup’s team uses handheld nets to gather the trash, which takes a significant amount of effort. The long-term goal is for a ship to visit the patch regularly to capture the collected plastic, which will be brought to shore to be recycled.
As The Ocean Cleanup plans to create a System 002 of the device, a few key challenges remain: How will the current device hold up during a harsh winter? Can the device hold plastic for months between pickups? 
“Our team has remained steadfast in its determination to solve immense technical challenges to arrive at this point. Though we still have much more work to do, I am eternally grateful for the team’s commitment and dedication to the mission and look forward to continuing to the next phase of development,” Slate said. 
But Slat said he remains positive. Once the challenges are assessed and fixed, The Ocean Cleanup plans to design a fleet of devices designed to rid oceans of their plastic. With the success of a fleet, the nonprofit predicts to remove 90% of the ocean’s plastic by 2040.
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