World Water Day 2017: 60 powerful photos to make you think twice about leaving the tap running

World Water Day is marked on 22 March every year to raise awareness of the water crisis facing much of the world's population. The UN estimates that more than 663 million people do not have a safe water supply close to home. Instead of turning on a tap, they must spend countless hours queueing or trekking to sources of water. This water is often contaminated, putting people at risk of infectious diseases and premature death.