Accessible fresh water is scarce, incredibly scarce when you look at the total amount of water on earth. The vast majority of that, about 97 percent, is sea water. Between 1.7 and two of the remaining three percent is permanently trapped in glaciers, ice and snow.
Most of the little that remains is ground water or soil moist. The surface water, which we can easily access - lakes, rivers and swamps - only accounts for 0.01 percent of the world's water.
While that covers the needs in places like Germany, Sweden, Argentina or Canada, the Global Water Institute estimates that 700 million people in 43 countries currently suffer from water scarcity. And conditions are set to get worse.
By 2050, UNESCO says more than 40 percent of the world's population will be living in areas of severe water stress. The UNCCD meanwhile predicts that by 2030, as many as 700 million people will be forced to leave their homes due to water shortages, aggravated by climate change.
The distribution of drinking water is even more uneven. While in Europe and North America, it is used to shower and flush toilets, WHO statistics suggest almost 800 million people in the world have no access to it at all.