Environmental impact of water-use in buildings: Latest developments from a life-cycle assessment perspective

Abstract

Globally, buildings are recognized as one of the highest users of freshwater resources. Consuming enormous amounts of constructional and operational water deplete water resources and ultimately generates a high environmental impact. This is mainly due to the energy required for the water cycle of built environments, which involves raw water treatment and distribution, use within buildings, and wastewater treatment. Moreover, the impact of water use varies significantly among countries/regions, due to different water use cycles. For example, many countries use conventional water treatments, while others rely on advanced desalination. Unlike building energy use, the impact of water use in buildings has not been captured fully in research. Given the significant impact of water use in buildings and global environmental degradation, we aimed to review studies concentrating on constructional and operational water use and associated environmental impacts, as well as studies that employed life cycle assessment (LCA) on this topic. The review indicated that a limited number of studies have focused on this serious issue in recent years, and their aims differed greatly. Therefore, there is a notable research gap in comprehensive environmental impact assessment including the total human water use cycle. Complete environmental assessment through LCA enables building professionals to understand the wide-ranging impact of water use in a building's life cycle from the environmental perspective in a given region. Additionally, this approach can benefit policymakers setting guidelines for new sustainable water strategies aimed at reducing environmental impacts.