A huge volume of fresh water has disappeared from the drought-struck south west of the US in the past decade in what researchers say is a startling sign of the fragility of one of the country’s most important water supplies. Almost 65 cubic kilometres of water has been lost since late 2004 from the Colorado River Basin , an area roughly the size of France that is a vital but heavily used source of water for more than 30m people and 4m acres of farmland. The amount lost was nearly double the volume of the Colorado River’s Lake Mead , the largest man-made reservoir in the US, according to a study by scientists using data from Nasa satellites that can measure changes in water levels. “This is a lot of water to lose. We thought that the picture could be pretty bad, but this was shocking,” said the study’s […]