Wastewater management in the Danube Basin

In the framework of the Environmental Program for the Danube River Basin financed by the PHARE-program of the EC-Commission the study “Nutrient Balances for Danube Countries” was carried out by the Department of Water and Wastewater Engineering of the Budapest University of Technology and the Institute for Water Quality and Waste Management of the Vienna University of Technology. Expert teams from seven further countries from the Danube Basin completed the team for the project. A crucial part of this study was the evaluation of the present situation of wastewater management of the different countries and the evaluation of future strategies for wastewater management in the context of nutrient balances. This paper presents the developed methodology for wastewater management and the results of its application to the Danube catchment. The major conclusions of the study are: to postpone sewer construction unless hygienic reasons and/or drinking water protection require it and to aim at upgrading treatment efficiency; an ambient water quality principle requires high treatment efficiency in many cases and by introducing nutrient removal at municipal wastewater treatment plants about 20% of the total nutrient emissions to surface waters can be removed.