Ocean Plastic Pollution: Engineering Solutions for the Great Pacific Garbage Patch

[00:00:00]In the summer of 2011, a 16-year-old Dutch student named Boy and Slatt went scuba diving off the coast of Greece. He traveled there excited to see the crystal and blue waters and vibrant marine life. Instead, he found himself swimming through waters polluted with plastic. [music] He later remarked that he saw more plastic bags than fish.

[00:00:18]>> And this was so shocking and disappointed that I asked myself the question, why can't we just clean this up?

[00:00:29]Last year, humans produced over 400 million tons of plastic. Stacked as plastic bottles, it would reach to the moon and back more than 7,000 times.

[00:00:37]Most of it is never recycled, and a growing share of this plastic ends up in the [music] ocean. If current trends continue, researchers project that by 2050, there will be more plastic in the ocean by weight than fish. So, why hasn't the ocean plastic problem been solved?

[00:00:53]The prevailing wisdom at the time was that cleaning the oceans was an impossible task. People argued that the sheer vastness of the sea made any extraction effort a drop in the bucket.

[00:01:01]Slatt estimated that using conventional vessels with nets would take thousands of years and cost tens of billions of dollars. People warned that the process would be carbon intensive and destructive to marine life. The National Ocean and Atmospheric Administration has estimated that it would take 67 ships one year to clean up less than 1% of the North Pacific Ocean. But Slatt refused to accept this conclusion and spent his final year of high school researching what he could do about the problem. He dove into the mechanics of ocean currents and fluid dynamics. He sought to understand why experts deemed this task impossible. And eventually [music] he arrived at a solution that seemed almost too easy. His high school science project proposed using the ocean currents to collect the plastic in concentrated areas. He realized that the natural circular currents of the ocean known as gys act like massive whirlpools that already concentrate debris. His design suggested placing long floating barriers in these gyers. These barriers would act as artificial coastlines, intercepting the plastic while allowing the current to flow underneath, carrying marine life to safety.

[00:02:05]After graduating high school, he started an aerospace engineering degree at Delft University of Technology, but he continued to work on his ocean cleanup ideas. By using these barriers anchored to the seabed, he theorized that the plastic would push itself into a central collection point, making extraction as simple as scooping up a concentrated pile of waste. And this concept won him the best technical design award at university.

[00:02:29]Then in 2012, he was invited to give a TED talk where he presented his work titled How the Oceans Can Clean [music] Themselves. Slatt made a bold claim during this talk. He said that the Great Pacific Garbage Patch could be cleaned up in just 5 years and that he had a plan to make that reality.

[00:02:47]After giving this talk, he decided to follow through on his plan and he quit his studies and founded the Ocean Cleanup in 2013 with just €300 of savings as starting capital. But a few months later, the talk went viral, gaining 3.3 million views on YouTube.

[00:03:02]And the nonprofit quickly raised over 2 million through a record-breaking crowdfunding campaign. and later he secured tens of millions of dollars from Silicon Valley investors. However, as we look at the state of the world more than a decade after his viral TED talk, the Great Pacific Garbage Patch still exists. It's actually accumulating more plastic at an accelerating rate with concentrations increasing exponentially since the 1970s.

[00:03:28]And the Great Pacific Garbage Patch is not the only problem. There are five major subtropical gyres worldwide, all of which act as massive collection zones for global waste. The Great Pacific Garbage Patch refers to an area between Hawaii and California where plastic and floating trash collects. Despite the common public perception of the patch existing as a giant island of floating garbage, its low density of only four particles per cubic meter prevents detection by satellite imagery and even by boers or divers in the area. This is because the vast majority of the plastic in these gyres consists of microlastics.

[00:04:02]These are tiny fragments less than 5 millimeters in size and they're the result of larger plastic items breaking down over decades due to UV radiation and wave action. The area covered by the patch is roughly 1.6 million km, often compared to three times the size of France. Microlastics account for 8% of the total mass, but 94% of the estimated 1.1 to 3.6 6 trillion pieces floating in the area.

[00:04:31]The integration of this plastic into the marine environment has also created complex ecological systems. A 2023 study in nature ecology and evolution found that dozens of species of coastal marine organisms are now living and reproducing on the plastic debris in the high seas.

[00:04:47]A phenomenon called the neopelagic community. Coastal species like anemmones, worms, and crustaceans.

[00:04:52]Organisms that evolved to live along shorelines have colonized a habitat made from plastic in the middle of the ocean, creating an entirely new biome. And now the question of how to remove the plastic without destroying these ecosystems has become a new challenge in marine conservation.

[00:05:08]According to Business Insider and Marine Research Institutes, removing this plastic is not as simple as scooping it up. This biological integration means that every year the plastic remains in the water, it becomes harder to extract without causing collateral damage.

[00:05:24]Once it is in the ocean, it is connected with marine life. It's too late to remove it.

[00:05:34]So, where is all this plastic coming from? The public image of ocean plastic is often a discarded soda bottle or plastic straw. Media campaigns have spent years focusing on individual littering and consumer choices. While reducing personal plastic is beneficial, it obscures the primary driver of the Great Pacific Garbage Patch. Research conducted by the Ocean Cleanup and various academic partners has revealed that the majority of the plastic in the patch originates from industrial activities. A 2022 study published in scientific reports indicated that roughly 75 to 86% of the floating plastic mass in the patch comes from the fishing industry. This includes massive commercial nets and plastic crates.

[00:06:14]Every year, an estimated 640,000 tons of fishing gear is lost or abandoned in the ocean. This is a systemic failure of industrial waste management within the global fishing industry. But boy still thought that he could solve it. Slatt's first major attempt to tackle the patch was known as system 001 nicknamed Wilson. It was a 600 m long floating pipe that sat on the water in a U-shape with a 3 m deep skirt hanging below it.

[00:06:39]The idea was that the wind and waves would push the system faster than the plastic, allowing it to act as a giant funnel. But the system struggled to maintain the necessary speed to keep the plastic inside the [music] array. Even more frustrating was the physical toll of the environment. Constant wave action caused structural fatigue [music] and a section of the massive pipe eventually broke off. The team had to tow the entire system back to port for repairs.

[00:07:04]Slatt was only 23 years old at this point. He had raised millions in public donations, gone viral around the world, and had made a very public promise. But now he was watching the first system fall apart after only being operational for 4 months. He was determined to keep trying and said system 001 was an important milestone. It was the first time we really tested our technology in its intended environment. After several iterations, the team launched system 002 known as Jenny.

[00:07:34]This version used active propulsion from two vessels to pull the barrier which proved far more successful. In its first major test, Jenny successfully removed 9,000 kg of plastic in a single hall, proving that the concept of large-scale extraction was possible. But from this work, Slatt realized something. Even if they perfected the technology to clean the Great Pacific Garbage Patch, they were only treating a symptom of the problem that started much closer to shore.

[00:08:02]A massive percentage of the numerical count of plastic particles entering the sea comes from onshore operations. This was a surprising conclusion to reach.

[00:08:10]The ocean cleanup had spent years and tens of millions of dollars building and refining ocean systems, admitting that those systems, even if perfected, couldn't solve the root problem, required a strategic rethink of the organization's path forward. So Slatt decided to pivot his focus to where plastic was really coming from.

[00:08:29]For years, the general assumption was that plastic entered the sea from every coastline and every river in the world.

[00:08:35]However, research revealed a much more concentrated reality.

[00:08:39]While there are tens of thousands of rivers on Earth, the vast majority of them do not contribute a significant amount of plastic to the ocean. Data showed that only about 1,000 rivers are responsible for 80% of the plastic emissions. These rivers are typically located in regions where rapid urbanization has outpaced waste management infrastructure. In many of these areas, the river is the primary method of waste disposal. During the rainy season, rising waters wash months of accumulated trash directly into the sea.

[00:09:09]This discovery changed the entire strategy of the organization. If they could stop the plastic in these 10,00 rivers, they could turn off the tap for the entire world's oceans.

[00:09:20]This led to the development of the Interceptor. The Interceptor is a solar powered autonomous vessel designed to sit in the mouth of a river. It uses a long floating barrier to direct trash toward a conveyor belt. Because the vessel is solar powered, it can operate 24 hours a day using batteries to operate at night. By stopping the plastic at the rivermouth, the team prevents it from ever reaching the gy where it would break down and then become part of the marine food chain.

[00:09:44]Interceptors have been deployed in some of the most polluted waterways in the world, including the Rio Ozama in the Dominican Republic and the Clang River in Malaysia. In 2018, Coldplay teamed up with the Ocean Cleanup and made an announcement. The ocean cleanup's work is vital. We're proud to sponsor Interceptor 005, aka Neon Moon 1, which will catch thousands of tons of waste before it reaches the ocean. Since then, Interceptor 005 has successfully removed 5 million kg of trash from Malaysia's waterway.

[00:10:14]One of the most highstakes moments for the project occurred in Guatemala at the Rio Motwa basin. This river is known for trash tsunamis, massive waves of plastic that rush down the river after heavy rains. The ocean cleanup team installed what they called interceptor trash fence, a massive high tension net system. The first time the rains came, the fence was put to the test against a river full of plastic. It [music] held and clean water flowed away into the ocean. The Ocean Cleanup has not abandoned the Great Pacific Garbage Patch. They've been improving their oceanic systems, moving from system 001 to system 03, which is significantly larger and more efficient. By 2021, system 002 had extracted a total of over 282,000 kg of trash from the ocean. The organization views ocean cleanup and river cleanup as two halves of the same problem. One handles the legacy plastic already in the system while the other prevents the problem from getting worse.

[00:11:11]>> Plastic pollution is one of the largest threats our oceans face today.

[00:11:16]It's very important that we have the belief that we can can do this.

[00:11:21]>> As the Ocean Cleanup looks to the future, their goal is to remove 90% of ocean plastic by 2040. Let me know in the comments what you think of their ambitious goal and subscribe for more content like this.