The Plastiki, a catamaran made of 12,500 reclaimed plastic bottles, is set to complete its 12,000-km voyage across the Pacific from San Francisco to Sydney, Australia, Monday.
The 19-metre vessel with a crew of six aboard was stalled by southerly headwinds just off the Australian coast Sunday afternoon, the Sydney Morning Herald reported.
The final leg of the Plastiki's trans-Pacific voyage would have to be made under tow from a motor vessel because the catamaran — unlike a single-hull sailing vessel — cannot sail into a headwind, the paper said.
The Plastiki expedition — brainchild of banking heir and ecologist David de Rothschild — is designed to raise awareness of plastic pollution and overfishing in the world's oceans.
The Plastiki's name is a play on the Kon-Tiki raft which Norwegian adventurer Thor Heyerdahl sailed across the Pacific in 1947.
The 12,500 recycled plastic bottles forming the vessel's double hull are packed together in a "pomegranate-like" structure and fixed to pontoons and held together with a fully recyclable plastic called Seretex and an organic glue made from cashew nut husks and sugarcane. Its masts are made of reclaimed aluminum irrigation pipes and its sails of recycled plastic fibres.
The Plastiki uses fully renewable energy sources including solar, wind and sea turbines, so the crew are disappointed their entrance into Sydney harbour will not be under their own power, the Sydney Morning Herald said.
"It is a little sad in a way being on a vessel that isn't actually sailing," de Rothschild told the paper in a radio interview. "We were hoping to arrive on Sunday so that more people would be able to come out and join the celebration but it is still exciting — this has been four years in the planning and we have been four months at sea."
The five men and one woman aboard the Plastiki set sail from San Francisco on March 20.
In the next four months they survived winter storms, sailing for weeks through an enormous swirling mass of plastic garbage the size of Texas in the middle of the Pacific, and those final pesky headwinds off Sydney harbour.
"We've spent four months at sea but have seen very little fish stock and only a handful of marine mammals," de Rothschild told AFP Friday. "That is a real sign that the oceans are in desperate need of our help."
British skipper Jo Royle, 30 — the only woman on board — told the Morning Herald she was anticipating the end of the incredible journey and some non-male companionship for a change: "I am looking forward to a girlie giggle and a glass of wine. Everyone on board has a job to do, we have two filmmakers and a photographer. We all have our roles and we also all have to do a watch. It has been a remarkable voyage."
As for the Plastiki, it will be be moored at Sydney's Maritime Museum for at least a month. After that, David de Rothschild said, "We may just recycle the whole thing."