Developing an ecological–economic assessment framework for urban wastewater systems: the case of Athens and Vils wastewater systems

Abstract

To achieve a good ecological status as proposed by the European Water Framework Directive (WFD; 2000/60/EEC) large investments from urban wastewater authorities are required. The Directive anticipates that cost-effective plans and their economic benefits will offset the high costs required for wastewater upgrading projects. However, urban waste water authorities claim that cost-effective measures are already in place and that little improvement can be made. Current valuation studies have focused either on ecological elements or economic aspects without offering persuading evidence on the cost versus benefits of upgrading projects. To this aim, the current study developed an ecological–economic valuation framework for the comparative assessment of the ecologically sustainable levels in receiving waters and the associated economic effects. The central Wastewater Treatment Plant in Athens (Greece) and the small treatment plant in Vils (Austria) are used as representative case studies.

Keywords:

• ecological–economic valuation
• marginal valuation framework
• comparative assessment

Acknowledgements

The present research is a part of the European research project ‘Cost-effective development of urban wastewater systems for Water Framework Directive compliance’ (CD4W 2003–2006 / EVK1-2001-00286). An older version of the paper was presented at the 15th Annual Conference of the European Association of Environmental and Resource Economists, Thessaloniki, Greece, 27–30 June 2007. I would like to acknowledge the valuable comments of the three anonymous reviewers and the editor, who substantially helped improve the paper.