How we helped Transport for NSW reduce greenhouse gas emissions from pavement materials and increase the use of recycled materials in road infrastructure.  

Since 2016, the Easing Sydney’s Congestion Program Office (ESCPO) within Transport for New South Wales (TfNSW) has been implementing technologies and methodologies to deliver an extensive program of urban arterial road upgrade projects sustainably and efficiently. While ESCPO goals focus on improving traffic flows, trip reliability and safety, AECOM identified the opportunity to use ESCPO as a platform for testing and promoting sustainability initiatives.  

The project has shown that greater adoption of cleaner and environmentally sound technologies is possible, and that the United Nations Sustainable Development Group targets are achievable with appropriate systems.ESCPO has been selected as a feature case study to be included in the Engineers Australia Climate Change Taskforce 

Driving results with new technology 

AECOM, as the Consultant Partner with ESCPO, has championed the implementation of various technologies that aim to reduce the greenhouse emissions of different pavement materials and increase the percentage of recycled materials used.  

Design improvements achieved significant carbon reductions using technologies including warm mix asphalt, EME2 (a high modulus asphalt created to build stronger, thinner pavements), recycled crushed glass, asphalt reinforcement grids, and recycled materials such as recycled crushed concrete. 

An embodied carbon assessment revealed a 78% reduction when using recycled crushed concrete instead of crushed rock. This also avoids the carbon impact from concrete disposal to landfill. We also saw an 8% reduction by using warm mix asphalt as a default mix for all projects, rather than hot mix asphalt, and an 18% reduction when using EME2, compared to a hot mix, for the rehabilitation works for Princes Highway with Acacia Road, Oak and Kingsway.  

AECOM also supported TfNSW’s ‘Sustainable Procurement in Infrastructure Initiative’. A bus lay-over project became the first ESCPO project to include fifteen sustainability requirements that will help achieve more sustainable outcomes through construction and operation. 

Extensive engagement and collaboration between TfNSW, contractors, asphalt suppliers, and material suppliers enabled the project’s success. The long-standing partnership contract increased the uptake of sustainability initiatives and has been a catalyst for the review and development of technical and contract specifications and industry positions regarding some of these technologies.