"David de Rothschild, 30, the founder of Adventure Ecology, will set out from San Francisco in April in an attempt to alert the world to the pollution threat from great Pacific garbage patch.
The area of ocean, known as the north Pacific gyre, attracts waste thanks to the circular pattern of the world's sea currents.
The United Nations estimates there are 46,000 pieces of plastic, most no bigger than a penny, floating on every square mile of the world's oceans which is devastating marine life.
The Pacific patch is the biggest concentration, with a plastic mass estimated at 3.5 tons.
Mr de Rothschild is calling his mineral water bottle raft the Plastiki, in honour of Kon-Tiki, the timber and hemp raft used by Norwegian explorer Thor Heyerdahl, who demonstrated South American Indians could have settled in Polynesia."