Life cycle assessment (LCA) of sewerage systems: a decision support tool to complement local impact studies

Abstract

Life cycle assessment (LCA) is increasingly positioning itself as a decision-making tool for the choice of treatment options and their technical management in synergy with more local approaches such as impact or risk studies. The article summarizes the LCA results obtained in small and medium-sized communities for very low load activated sludge treatment plants and reed filters. It then analyzes the sewerage system as a whole by presenting the contributions to the various environmental impacts of the plant and the collection system. Finally, it outlines the prospects, in particular with regard to a better consideration of the LCA of pathogens and micropollutants, in order to better evaluate "tertiary" treatments. In addition, educational inserts will detail the LCA method with a focus on certain categories of impacts such as eutrophication or ecotoxicity.