Feasibility evaluation in reclaimed water reuse projects through the analysis of some case studies

In reclaimed water reuse projects, the focus is generally to investigate and develop technical issues (most adequate treatment selection, water quality in the final effluent and its allowed variability, and satisfaction of water demand). Sometimes investments, as well as operational and maintenance costs, are also estimated and reported with regard to the construction or upgrading of the wastewater treatment. Less frequently, projects also include an economic evaluation that considers the costs and benefits related to the development of the project, in order to evaluate whether the project is feasible from both a technical and an economic point of view. This evaluation may be performed at different levels of analysis both in terms of costs and benefits. This chapter presents how the feasibility of reclaimed water reuse projects may be performed in both technical and economic terms through the presentation and discussion of a selection of projects for direct reuse for irrigation and recreational purposes. It emerges that different types of benefits may be considered and evaluated using different methods, including the contingent valuation method and the travel cost method. The chapter aims to provide new insights for a more comprehensive technical and economical evaluation of reclaimed water reuse projects. The approach followed is to discuss applied methodologies without entering into the analysis of the collected results in specific case studies. For this reason, data are reported only in those cases where exemplification may help understand the project development. The chapter concludes with some considerations on decision-support models: more complex tools which can help conduct a technical and economic feasibility analysis of the project.