Removing salts and other impurities from water is really difficult. For thousands of years people, including Aristotle, tried to make fresh water from sea water. In the 21st century, advances in desalination technology mean water authorities in Australia and worldwide can supply bountiful fresh water at the flick of a switch.

Achieving water security using desalination is now a priority for the majority of Australia’s capital cities, all but one of which are on the coast. Using the abundance of sea water as a source, this approach seeks to “climate proof” our cities’ water supplies.

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