It's a work of modern art and an engineering marvel -- a 60-foot catamaran kept afloat by recycled plastic bottles.
It only takes 12,000 bottles to do the job. Each is filled filled with carbon dioxide, making the bottles so rigid that a truck could drive over one and it wouldn't break.
The sail is made of plastic rather than cloth, and even the mast is repurposed irrigation pipe. The exterior surface is fabricated from plastic too, instead of the usual fiberglass.
The one-of-a-kind vessel has a name to go along with its unusual materials -- she's christened the Plastiki.
"It's very likely that people in the San Francisco area might have a bottle they've drunk in the Plastiki," said the ship's creator, David de Rothschild. He's the heir to the famous banking fortune, and he says the boat is a way to draw attention to major environmental problems caused by waste plastic.
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"We're needlessly losing millions of seabirds and hundreds of thousands of marine mammals from injesting plastic every year," de Rothschild said. "I decided to take this 'out of sight, out of mind' problem and build a boat out of the very items that we were seeing ending up in our natural environment."
The crew will shove off aboard their plastic bottle boat, traveling from San Francisco on a three-month voyage to Sydney, Australia. That's a 11,000-mile trek across some very treacherous seas, and they can only hope that the bottles are up to the job.
"The boat is incredibly sturdy," said de Rothschild. "The superstructure material that we've engineered is very, very strong, almost comparable to fiberglass."
On the journey, they'll pass by enormous swaths of garbage floating in the middle of the Pacific Ocean. The masses are made of millions of pounds of plastic debris that has gathered in the current and clustered together. One of the mounds is twice the size of Texas -- a vivid image, say the sailors, of how much we waste.
The crew hopes the Plastiki will shed light on a global garbage problem.
"I hope it inspires people in their everyday lives to just sort of think about those little things that they can do to make that big difference," de Rothschild said. "I think we all have a responsibility to act, to try to do something about it because I think it's one of those problems we can solve."
The Plastiki's crew members plan to begin their journey in the next few weeks. The oceans are imperiled, they warn. And they hope to send that message to the world in a plastic bottle.