Evaluation of water efficiency programs in single-family households in the UK: A case study

Current water supply worldwide is facing growing pressure as a result of climate change and increasing water demand due to growing population and lifestyle changes. The traditional way of fulfilling the growing demand-supply gap by seeking new water supply options such as exploiting new fresh water resources and investing in the expansion of infrastructure is no longer considered environmentally or economically sustainable. A diverse portfolio of water efficiency measures is now a requirement for the majority of water companies in the UK. This paper presents results from a statistical analysis of a unique water efficiency program case study. Specifically, the study evaluates the effectiveness of installing water-saving devices in single-family households in areas where a major UK water supply company operates. Moreover, we examine the factors that influence water consumption of the households in these areas, defining the relationship among daily per capita water consumption (pcc), weather- and household-specific demographic variables. This study can be a valuable asset to water companies as it provides a review of program evaluation procedures and their limitations focusing on a detailed implementation of multilevel modelling, adding to the very limited implementation of the technique in the water efficiency literature. Most importantly, this research attempts to draw attention to common data limitation problems that most companies experience, and suggests possible ways to overcome them.