Assessing the quality of service to customers provided by water utilities: A synthetic index approach

•Development of synthetic index of quality of service to customers.•Benchmarking the quality of service of water companies.•The aggregation of indicators eases the decision-making process.

Currently, water and sewer companies face the challenge of improving their quality of service to customers (QSC). Performance indicators are essential to monitor and benchmark the QSC of water companies; however, individual indicators do not provide a holistic evaluation of the quality of water and sewer services provided to customers. This study proposes an innovative QSC index based on distance-function techniques that makes it possible to compare changes in the QSC of water companies among locations and temporal periods. A case study assesses changes in QSC for a sample of Chilean water and sewer companies from 2007 to 2014. The results show that in spite of the efforts made by the water regulator, QSC has remained almost constant over a number of years, with 2010 having the best performance. The methodology proposed in this study is useful for water regulators to benchmark water companies when developing policies that prompt QSC improvements.