DEA AS A USEFUL TOOL FOR ASSESSING THE ECONOMIC EFFICIENCY OF WASTEWATER TREATMENT PLANTS

Project of wastewater treatment plants (WWTPs) should be evaluated in terms of environmental, economic and social sustainability. The EU Water Framework Directive (WFD) encourages all European countries to pay attention to the efficient utilization of natural resources and the impacts of human activities on the water. This article was focused on the implementation of an assessment tool for the economic efficiency of WWTPs, which can be employed as supplementary to the traditionally methodologies. Wastewater treatment processes produce desirable outputs (treated water) together with undesirable pollutants, and inputs are related to the cost of the operation and maintenance. The efficiency evaluation was provided through the use of the Data Envelopment Analysis (DEA) across a sample of the WWTPs in the South Moravian Region in the Czech Republic. This non-parametric method, which is based on linear programming, divided these functional units into effective and ineffective scores. The obtained results can be of help to managers during the ex-ante decision-making process and also for ex post evaluation with a focus on factors of success and failure and on the sustainability of results and impacts. Finally, the DEA was successfully used in many previous studies for the calculation of techno-economic efficiency.