The Ocean Cleanup: A great catch

The brainchild of a Dutch teenager, The Ocean Cleanup aims to clear our seas and rivers of waste through engineering. Kathryn Manning investigates

The story of Boyan Slat, and his idea for capturing the plastic waste in our oceans, has also captured the world's imagination. At the age of 16, the Dutch inventor and entrepreneur was diving with his family in Greece, and became shocked that there were more plastic bags in the sea than fish. On returning home, he decided to dedicate a school science project to finding solutions to the ocean waste problem.

The first challenge was the Great Pacific garbage patch – a swirling mass of debris that is more than twice the size of France, at 1.6 million square kilometres in size. “I'd always been interested in engineering, and then came up with a concept of how I thought we could feasibly clean the ocean garbage patches,“ Slat said. And so the idea for The Ocean Cleanup was born.

The system he developed consists of a long buoyancy barrier that sits at the surface of the water, and a 'skirt' that hangs beneath it to collect debris. The skirt prevents debris from escaping underneath and leads it into a retention system, but as a passive system, it does not capture or affect wildlife.

“Our mission is to have removed 90% of all ocean plastics from the concentration zones in the five gyres by 2040“

The following year, in Delft, while studying aerospace engineering, Slat presented a TEDx Talk describing his new creation. At just age 18, he decided to drop out from university and devote all his time to the non-profit entity The Ocean Cleanup. His TEDx Talk went viral after being shared by several news outlets, enabling him to raise funds and assemble a team of 100 people to study the concept's feasibility.

Fishing for success

In just two short years, Slat had both conceived and put it into action his plans for Ocean Cleanup. At this time, the world was only just waking up to the damage that the millions of tons of plastic entering our oceans each year was doing to wildlife, ecosystems and even our own food chain. Most plastic comes from polluting rivers, and much ends up in huge ocean garbage patches, of which the Great Pacific is the largest.

Now, however, there was an operation with a clear plan. And with US$2.2m raised through Slat's crowdfunding campaign, and $31.5m raised in donations from entrepreneurs in `Europe and Silicon Valley, the team's optimism was clearly contagious.

Joost Dubois, head of communications at The Ocean Cleanup, outlines the goal: “The mission is to develop technologies to rid the world's oceans of plastic, and to have removed 90% of all ocean plastics from the concentration zones in the five gyres by 2040. In order to reach that goal, we calculated early on that we also needed to stop the influx, since the gyres are growing at an exponential rate.“

“Our aim in the river project is to tackle the 1,000 highest-polluting rivers around the world in five years' time from launching the Interceptor“

As the majority of plastic in the ocean comes from polluting rivers, the next step was a solution to catch the waste before it reached the ocean. “We developed the Interceptor technology, which we presented to the world on 26 October 2019, after more than four years of quiet development,“ explains Dubois. “This occurred weeks after we confirmed the concept of our ocean approach to be working, and right before we brought the first catch of ocean plastic back to shore in December.“

This was a high point for the team, after what had been some challenging moments during the initial 'Ocean' phase of operations. The first 001 system, nicknamed 'Wilson', suffered several major setbacks, including a fracture in January 2019 that meant it had to be towed to Hawaii for repairs. However, the team took these lessons as a 'learning curve', adapting the floating device with every lesson.

Sink or swim

What was the most difficult problem during the project? “There are almost too many moments to choose from,“ he says. “What we are aiming to do is not easy, but the beginning of last year does stand out as a trying period of time.“ This was when Wilson had broken in two, and the team knew that the long-awaited moment of bringing its first plastic catch to land was further away than expected. “Our resilience was definitely tested then,“ Dubois says. “At the same time, our first Interceptor prototype had been stuck in customs for months, making the moment of first deployment of our river system hard to predict. All in all, these hurdles made the start of 2019 rather tough for all of us.“

While some might say that teething problems are inevitable when dealing with new technology, some scientists and journalists criticised the operation, complaining that the media attention was drawing the focus away from better developed solutions. How did the team deal with these accusations? Dubois takes a scientific approach: “We do take critical input into account in defining our next steps,“ he says. “Certainly when it is founded in good data, this is invaluable input. The latter does not count for all critical input, however. We make a rational analysis of everything we hear – which is a great mechanism in order to be resilient to unfounded criticism, in our experience.“

Going to the source

Does the team ever challenge the industry that actually creates the plastic waste? “While we believe it is important to understand the problem, our efforts and focus stay on the solutions,“ Dubois says adding, “We think we are at our best when we focus on what we are good at: developing technology. The problem is too complex to point at one original source as the cause of ocean plastic pollution.“

Indeed, with the ocean project now a success, it made sense for Slat and the team to concentrate on those sources it is designed to deal with: rivers.

“Our aim in the river project is to tackle the 1,000 highest-polluting rivers around the world in five years' time from launching the Interceptor,“ says Dubois.

Four Interceptors have been built to date; two are in operation in Jakarta (Indonesia) and Klang (Malaysia), one is waiting for deployment in Vietnam, and the fourth is being transported to the Dominican Republic. In addition, Thailand has signed up to deploy an Interceptor near Bangkok, as has Los Angeles County, California, kick-starting the programme in the West. “During this crucial testing phase, we focused on specific locations,“ says Dubois. “Now that we are ready for roll-out, our ambition is, with the help of local governments and operators, to start deploying Interceptors in the most polluting rivers all over the world.“

This roll-out is dependent on funding, and Slat does see his mission as a race against time. According to The Ocean Cleanup's research, just 8% of the plastic mass in the Great Pacific garbage patch is currently microplastics – but this will soon change. “What's going to happen over the next few decades is that all the other 92% of plastic will be turned into microplastics as well,“ Slat has said. “So the sooner we get it out, the better.“

The Ocean Cleanup aims to turn the plastic waste it captures into objects that are not single-use. Again, he and his team's faith in technology, and humankind's ability to create solutions, is inspiring.

“Technology is the most potent agent of change. It is an amplifier of our human capabilities“, Slat wrote in The Economist. It is this message of hope that has caused enviromentalists, scientists and the general public alike to get on board and support this ambitious operation.