Assessing the Environmental Impacts of Household Water Supply: A Case Study Considering Consumption Patterns within a Life-Cycle Perspective

Household water supply can cause different environmental impacts associated with the consumption of energy and materials, the generation of waste, and other inputs and outputs necessary to treat and distribute water. These impacts depend on the population's consumption patterns, due to the potential availability of different water sources. In this work, the environmental impacts of water supply were evaluated from a production-consumption perspective, integrating life cycle assessment (LCA) and a survey for determining the end uses and sources of water at household level. The proposed method was applied in the city of Chillan (Chile), where three main sources exist: tap, bottled, and well water. Two household profiles were evaluated, differentiated by the presence of wells within the household. The results show that bottled water generates impacts up to three orders of magnitude greater than the other sources. Although it is the source with the lowest volumetric contribution (<1%), it accounts for 39-92% of the household impacts. Households with well access present greater per capita consumption of water, mainly associated with outdoor activities, but the environmental impacts are similar between profiles. Overall, this study demonstrates the importance of integrating a consumption perspective into LCA studies, generating better information for decision-making.