Municipal Wastewater Treatment Policy Referring to EU Guidelines and its Impact on Receiving Waters from Rivers to the Receiving Seas

Abstract

Water Management has become a very important has become a complex integrated management task. With EU Framework Directive it will be compulsory to make water management plans for river basins including the affected estuaries. Municipal waste water management as part of urban water management has to be integrated into these plans. It is therefore necessary to discuss the waste water treatment policy in regard to the influence on the receiving water quality. With decreasing dilution of the treatment plant effluent by the receiving water the influence of the treated waste water on pollution concentration will increase, while the pollution load is not affected by dilution. As the receiving waters of most of the Central and Eastern European countries have international river basins discharging to land locked seas with sensitive estuaries minimum treatment efficiency requirements should take this into consideration. The decisions have to be based on political, ecological and economical considerations. The Austrian experience can be used to demonstrate the consequences of 4 decades of consequent water protection policy and to illustrate the adaptation to EU directives, especially to the Urban Waste Water Directive 271/91.