Meet Plus Pool, the floating public swimming pool that has been designed for dirty city rivers filled with sewage. So, why would you want to swim in it?
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The pool can float in any body of water, including the River Thames, and filter it without using any chemicals. It can even filter wildlife, rubbish, bacteria and viruses.
Plus Pool is capable of holding 5,000 swimmers and would clean 600,000 gallons of water every day - how's that for eco-friendly credentials?
It was first designed with New York's East River in mind and if successful could be installed for swimmers in cities around the world.
Like the idea of swimming in a pool with a difference? Check out more of the most incredible public pools around the globe.