The full devastation wreaked by Germany’s cataclysmic floods has emerged slowly. As the waters subside, survivors have cautiously waded back through the mud and rubble to salvage what is left of their communities. Last week an unusual zone of low pressure trapped between two areas of high pressure meant that two months’ rain fell in 48 hours. The Ahr, Erft, Swist, Trierbach and Volme, usually less than a metre deep as they wind through small towns and villages on their way to the Rhine, were transformed into fierce and destructive torrents.