'An antidote to city life': the rise of chemical-free pools

Fans of wild swimming have been evangelical about natural water for years - and more cities are taking the plunge with chlorine-free public pools

"There is a peacefulness you get from natural water that you don't get from sterilised water," says Tim Evans. As one of a growing number of people developing chemical-free swimming pools, he would say that - but he's far from alone. In recent years, fans of wild swimming have been almost evangelical about the restorative powers of propelling yourself through the silky, skin-pricklingly-cold water of seas, rivers and ponds.

And now there are signs that British people are after a more natural experience from our swimming pools, too, after years of counting lengths in bright, heated leisure centres in water treated with chlorine.