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 13 increasing water demand due to growing population and lifestyle changes. The traditional way of 14 fulfilling the growing demand-supply gap by seeking new water supply options such as exploiting new 15 fresh water resources and investing in the expansion of infrastructure is no longer considered 16 environmentally or economically sustainable. A diverse portfolio of water efficiency measures is now 17 a requirement for the majority of water companies in the UK. This paper presents results from a 18 statistical analysis of a unique water efficiency program case study. The study evaluates the 19 effectiveness of installing water-saving devices in single-family households in areas where a major 20 UK water supply company operates. Using multilevel models, the study accurately measures the water 21 savings achieved through the efficiency program and defines the factors that affect a household’s 22 potential to save water. Analysis illustrated a mean 7% decrease in consumption, explicitly 23 attributable to the efficiency program. Research findings provide strong evidence that single resident 24 and financially stretched households have a bigger potential to conserve water than larger and more 25 affluent ones and also highlight the robustness of multilevel analysis, even in cases of data limitations.