Ships sent to clean Great Pacific Garbage Patch in middle of ocean return to SF

SAN FRANCISCO (KGO) -- Floating in the middle of the ocean is a giant collection of trash and debris that's come to be known as the Great Pacific Garbage Patch.

The accumulation of plastics, cans and other waste has become one of the most prominent examples of the environmental crisis engulfing the planet -- threatening not just marine life, but also humans.

"Plastic pollution is one of the largest threats our ocean faces today. It's ravaging ecosystems. There are more than 100 species facing extinction because of plastic," said Boyan Slat.

Slat is the CEO of a company called The Ocean Cleanup.

Six years ago, the company sent two ships out to the garbage patch in an effort to develop technology to clean it up for good.

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On Friday, those same two ships made their way back into San Francisco Bay.

This time, they have developed the technology needed for the massive undertaking.

Slat said the only thing preventing that from becoming a reality now is money.

"Once that is secured, we can ramp this up in about two, three years and the clock starts running. We can clear up the patch in potentially just five years," Slat said.

Slat estimates the total cost would be somewhere between $4-7.5 billion.

MORE: How one Bay Area team is responding to increasing threat of plastic pollution to world's oceans

It's small price to pay, said Matthias Egger.

Egger was one of the scientists on the expeditions who helped develop the technology needed for the cleanup.

It is a system of netting, cameras and computers powered by artificial intelligence.

"You have big waves, and you have a harsh environment. And to build something that's actually surviving out there, while at the same time only making sure you're catching plastic and not marine life, that was quite a challenge," Egger said.

Once the trash is pulled from the sea, it's then sorted on the ships and ultimately recycled.

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Egger took time to point out to us the glasses he was wearing being one of the recycled products that's been made.

"The stuff out there has value, it's not only trash. It's also a resource that we can use," Egger said.

Despite the steps that still need to be taken, Slat says he's optimistic about getting the patch cleaned up.

It's one step he hopes would inspire others to tackle even more of the environmental issues of our time.

"For humanity to thrive, we need to be able to be optimistic about the future. And I think if we can clean up the Great Pacific Garbage Patch, this seemingly insurmountable thing, I think is going to be an inspiration for many people," Slat said.