Measuring the environmental performance of urban water systems: a systematic review

This systematic review aims to understand how previous studies have determined the environmental performance of urban water systems (UWSs) and to identify the main environmental impacts caused by these systems and their respective sources. A systematic review strategy based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was used. The publications were selected by searching the Scopus and Web of Science databases last updated on 08 February 2022 and according to the eligibility criteria that were set for the present study. A total of 25 publications were analyzed in their entirety. Six publications presented methodological contributions by proposing frameworks and models for the analysis of environmental and sustainability parameters of urban water and sewage systems. Nineteen publications conducted case studies where life cycle assessment (LCA) and mass balance methods were employed. The categories of environmental impacts most frequently analyzed in the publications included climate change, eutrophication, acidification, and human toxicity. Moreover, the sources of these negative impacts were identified as high electricity consumption, chemical use, and nutrient discharge into the environment. The present review analyses the contributions to each stage of the systems that are associated with the characteristics of the systems and the level of detail of the used data.