Investigation of waste diversion rates in the construction and demolition sector in Australia

Purpose: Waste diversion rate (WDR) is a key indicator of effective waste management and circular economy. However, it has not yet been widely used in the construction and demolition waste (C&DW) sector. This study aims to promote the application of WDR as an effective measure for waste management through the investigation of the current status of C&DW diversion in the Australian construction industry. Design/methodology/approach: A mixed-method approach, which combines a desk study and a case study of 12 residential projects was used in this study. Data retrieved from the National Waste Database (NWD) were used for the descriptive analysis. Findings: The analysis of the national waste data revealed that the national average WDR in Australia is 64%. WDR varies based on material types and across the states. The analysis facilitated the forecasting of the possible future trend of waste diversion in Australia. The studied projects from two states in Australia presented slightly different results. Most of the waste stream, except mixed waste, presented above 95% of WDR in each project. Research limitations/implications: Although the studied projects showed a higher recycling rate, this study claims that achieving a higher rate of recovery by diverting the waste could not be assured unless accurate estimation is carried out with reliable and verifiable data. Lack of reliable data is considered as the limitation of this study. While the scope of descriptive analysis of waste generation and diversion covers the whole country, the case study analysis is limited to the states of New South Wales and Victoria. Originality/value: The study highlights the significance of WDR in assessing the performance of effective waste management in the C&DW sector. WDR is a comprehensive measure that takes the output of the waste life cycle into account for benchmarking waste management. The results provide a critique of the current practices of waste management and the essence of the consistent, transparent and verifiable waste data to enable accurate WDR estimation in Australia. The outcome is useful for waste managers and policymakers in developing potential waste management strategies and C&DW specific legislation for building a more ecologically sustainable industry.