A composite indicator for measuring the environmental performance of water, wastewater, and solid waste utilities

The aim of this paper is to measure and benchmark the environmental performance of Portuguese utilities jointly active in the three sectors of water supply, wastewater collection and solid waste management. To do so, we suggest the use of a traditional (optimistic) directional distance Benefit of the Doubt index. We complement the analysis by considering also the pessimistic version of the proposed BoD and by implementing a robust and conditional approach. The obtained results show that there is space for improvement in the pressure balance of these utilities, especially for small and very large units, mostly operating in urban areas.