Concrete Water Footprint Assessment Methodologies

Abstract

Concrete is the single most widely used material in the world and is only surpassed by water in terms of consumption. By 2013, 4 billion tonnes of Portland cement were produced worldwide, enough to produce about 32 billion tonnes of concrete, which represents more than 4.6 tonnes of concrete per person per year. The high water consumption and large amount of wastewater generated in the concrete industry has become a very important environmental issue. Due to the large global use of concrete, it is essential to correctly assess the environmental impacts of this material including impacts related to water consumption. Life cycle perspective is important because it allows identifying and reducing water related potential environmental impacts associated with products. In concrete life cycle assessment, these impacts are not considered mostly because of lack of data. There are several methodologies for water footprint assessment, as The Water Footprint Assessment Tool and the ISO 14046:2014 standard -that is based on life cycle assessment (ISO 14044)-, as well as sustainable reporting guidelines, which include water assessment for organizations. The aim of this paper is to evaluate existing water footprint methodologies based on life-cycle assessment, their concepts and difficulties, and link them to concrete industry. Out of at least eighteen existing water footprint methodologies, it was found that four of them are feasible for cement based materials industry, however there are differences between the definitions and criteria adopted by each methodology.

Life cycle water footprint assessment of concrete production in Northwest China

“…In the concrete industry, Netz & Sundin (2015) put forward the evaluation method of concrete WF in 2015. Mack et al (2016) proposed a simplified method for measuring WF of concrete in 2016. Bardhan (2011) calculated the consumption of water resources in Indian construction.…”

“…Using the 2015 global concrete production data, Vergara & John (2019) estimated that the global concrete water consumption is about 180 Â 10 8 m 3 (63.2-304.3 Â 10 8 m 3 ), and the WF is about 0.547-2.634 m 3 /ton. These studies further deepen the application of WF in concrete water management, but the research on the WF of concrete production is still insufficient (Mack et al, 2016). Concrete production causes severe environmental problems due to the large amount of water consumed and wastewater produced.…”