The worst storm event in the last 100 years caused 3 billion CHF in damage. The damage in the private sector was unusually large (2.5 billion CHF). First analyses showed the value of warning systems, however weak points are apparent. One week after the flood the Federal Council decided to strengthen the hazard prevention and established the new Federal Office for the Environment. The Federal Council delivered a mandate to evaluate the status of warning and alert systems. Current experience shows that a very large potential for improvement is available in the field of warning and alarm systems. Due to the high level of effectiveness, the improvement of warning at the federal level has been assigned the highest priority. Hazard maps are an indispensable prerequisite basis for this purpose.