The world has abundant fresh water but it is unevenly distributed and under increasing pressure, United Nations agencies say, as highlighted by the drought in Cape Town. On Tuesday South Africa declared the drought that has hit parts of the country and threatened to leave the Mother City without domestic tap water a national disaster. More than 97% of the planet’s water is salty, most of it in the oceans and seas. But every year about 42.8-trillion cubic metres of renewable fresh water circulates as rain, surface water or groundwater, according to the UN’s Food and Agriculture Organisation (FAO). This equals 16 216 litres a person a day — four times the amount required in the United States, for example, for personal and domestic consumption, industry and agriculture. Depending on diet and lifestyle, a person needs between 2 000 and 5 000 litres of water a day to produce […]