More than 1.5 billion people live in countries suffering from water scarcity, which is when supplies drop below an average of 2,750 litres per person per day. This hampers food production and economic development, making communities particularly vulnerable, and has serious consequences for human health – with poor sanitation the world’s leading cause of premature death.
As human populations continue to expand, the world’s fixed supply of freshwater will have to stretch ever further. And on top of that, climate change is altering evaporation and precipitation patterns, so while an excess of water may occur at times or in places with no infrastructure to deal with it, some existing water sources are expected to dry up. The world’s two most water-short regions – Africa and the Near East – have the fastest-growing populations, and may also suffer extreme drought conditions associated with climate change. Putting climate change and population growth together, the number of people living with water scarcity is set to more than double during the coming decades.
People are working to squeeze every drop from the available resources, introducing techniques that range from the very high-tech – including desalination – to simple storage systems, like water butts, that can be installed at home.