A study of liquid waste management practices in construction projects in Australia

The construction industry is increasingly under pressure to improve environmental performance and reduce environmental degradation, which often results from carbon emissions and a high volume of waste generated from unprecedented levels of development associated with urbanisation and industrialisation. Construction projects consume a significant amount of water at the same time; they generate liquid waste (LW) from several wet processes during construction on-site, which is often unmetered. At the same time, LW or wastewater generated from construction projects is detrimental to the environment and human health, adversely polluting the surface and groundwater as well as the ground soil. It is, therefore, indispensable to manage LW appropriately while utilising the water efficiently. Limited studies have paid attention to explore the importance of effective liquid waste management (LWM) practices in construction projects and their implications on environmental sustainability. This study aimed to investigate the current practices of LWM in construction projects through the analysis of expert user views and quantitative data analysis while providing an account of LWM related legislative requirements. Moreover, this study estimated the average volume of water consumed for tool washing and water saving for different types of projects and compared it against the use of sustainable LWM systems, notably a closed-loop washout system employed in construction projects. The outcome of this study has the potential to add new and under-measured factors to the current LWM systems and to promote sustainable LWM practices in construction projects. While it highlights issues related to LWM, it provides criteria that can be considered for the green rating of buildings.