Status of decentralised wastewater treatment systems and barriers for implementation of nature-based systems in central and eastern Europe

The aim of this paper is to present a survey on the current status of wastewater treatment systems in 11 central and eastern European (CEE) countries, with a focus on rural areas and on small treatment wetlands for settlements of below 2,000 people. The results indicate that CEE countries have insufficient sanitation systems with different performance efficiencies. These differences stem from the different historical, political and economic developments as well as legislation in the previous five to six decades. CEE settlements with less than 2,000 inhabitants represent almost 30.0 % of the overall number of persons living in CEE countries. These data show that CEE countries have a mainly rural character, but this is slowly decreasing. Over 42 million inhabitants are waiting for proper sanitation systems. This requirement will be ever-growing in the next future, and it is important to know and to prepare appropriate steps for progressive realisation.