Water is one of the world's most precious resources.
But in many countries, climate change and growing populations are making it increasingly scarce.
A large number of countries, including Australia, are ranked as having a high level of water stress. They are easing the shortage by taking water from the sea.
When a desalination plant near Melbourne opens later this year, it will be Australia's fifth and the world's second-biggest. It will be able to fill 1,000 Olympic-sized swimming pools with drinking water every day - which is a third of all Melbourne's water needs.
Al Jazeera's Andrew Thomas reports from the state of Victoria.