Germany's Federal Environment Agency estimates that a quarter of all German groundwater contains excessive concentrations of nitrates - threatening some communities' water supply. The cause is over-fertilization of farmers' fields. Germany, Austria and Switzerland have been successfully joint-monitoring Lake Constance water quality for years.<br /> <br />But authorities in Lower Saxony are only beginning to tackle the problem. Drinking water there often exceeds the EU norm of 50 milligrams of nitrates per liter.<br /><br />Global 3000 home page: http://www.dw.de/program/global-3000/s-11487-9798
