The Roads to Reuse (RtR) program is the Western Australian Waste Authority’s flagship C&D recycling program and provides high-quality recycled C&D products in civil applications.
Sustainable construction
Developed between the State Government and Waste and Recycling Industry WA, it closes the loop on C&D recycling, reduces waste to landfill, recovers valuable materials and creates local jobs.
RtR products are recycled road-base and recycled drainage rock. Recycled road-base – or crushed recycled concrete (CRC) – consists largely of concrete produced from the crushing and screening of C&D waste. RtR recycled road-base can be used as sub-base or base-course in sealed road and pavement construction and other sealed hardstand areas. State and local governments have used RtR products in projects, with results demonstrating reduced project costs and high performance. The RtR product specification is setting the standard for manufacture and quality control.
RtR reduces natural resource use and carbon emissions, and local processing and availability in high-demand areas mean reduced transport costs and emissions. Use of recycled construction products by governments sends a clear message that they are delivering on Environment, Social and Governance (ESG) commitments for new infrastructure projects.
The road to recovery
The RtR program started life in a 2019 pilot, a freeway widening project in Perth’s southern suburbs with 25,000 tonnes of CRC sourced from the demolition of Subiaco Oval.
The project focussed initially on supporting the production of RtR products consistent to meet the RtR product specification. The project also includes an independent audit of producers’ processes and products to provide an additional level of assurance to purchasers. It provided prospective buyers with confidence in the final product and opened the door to a partnership with the State Government’s Main Roads agency.
Main Roads has now used more than 165,000 tonnes of RtR products in various projects. Having proven its performance and benefits, Main Roads only permits RtR-sourced CRC in road pavement construction and is committed to increasing the use of recycled materials.
A number of State Government METRONET projects have also used RtR-certified CRC with more than 15,500 tonnes used for projects such as level crossings and retaining wall blocks. Materials are only available from accredited suppliers, ensuring rigorous criteria, systems, processes and independent oversight that means environmental assurance and transparency for purchasers.
Local government applications
Local governments can now experience the benefits of RtR applications firsthand with a growing number of civil applications. Engineers are finding it delivers high strength and durability, with self-cementing properties and increasing hardness over time. That means it’s workable and provides a tight surface finish. It requires less mixing and produces a material that works like conventional granular materials. Use of RtR products also helps local governments meet project and sustainability goals, such as:
- Water saving because less water is required for compaction than traditional limestone sub-base.
- Reduced labour costs, increased durability over raw material and lifecycle cost reductions.
- Reduced transport costs because of local availability.
- Contributes to ESG outcomes for new projects.
- Elevates ISCA sustainability evaluation ratings for the economic, social and environmental performance of infrastructure assets throughout their lifecycle.
The Waste Authority is offering financial incentives to encourage local governments to experience the benefits. The RtR Local Government Incentives program is available to all Western Australian local governments and regional councils sourcing product from accredited RtR suppliers.
City of Gosnells uses Roads to Reuse
City of Gosnells, in the Perth metro region, recently completed the Crescent Shared Path project, which connects one of the missing links on the Principal Shared Path (PSP) network between the CBD and Armadale in Perth’s south-east.
The new section of path is 1.1 km long and runs the length of the adjacent rail reserve. The path is generally 3m wide but narrows to 2.5m at some locations to avoid impact to trees. The new shared path will tie into the existing PSPs. The project was funded jointly by the City of Gosnells and Department of Transport.
Highlights include:
- Following the boxing out and compaction of the sub-grade, the RtR recycled road-base was applied in lieu of limestone sub-base, water-bound and compacted ready for the application of kerbing, asphalt seal and line marking.
- The existing mature trees were able to be retained and incorporated into the design, allowing the path to wind around the trees and weave through the shade of the canopy.
- 300 tonnes of recycled road-base was used during the project, along half the length of the path
City of Gosnells Mayor Terresa Lynes said the City is committed to proactive waste management and sustainability.
“Using recycled construction materials to build the shared path at The Crescent in Maddington was a perfect opportunity to demonstrate this commitment – and to prevent a substantial quantity of construction waste material going to landfill,” Mayor Lynes said.
Meeting future needs
C&D waste makes up about half of Western Australia’s waste stream and with good management practices, most of it can be recycled. As demand for building and construction continues to increase, so too will the opportunity to use high-quality recycled materials. Having supported product development, pilots and a growing network of accredited suppliers, the Waste Authority’s focus is now on ensuring governments and other buyers are aware that RtR material is ready, available and consistently delivering high performance.
The RtR program is an example of how collaboration across industry and government is fostering a circular economy, and has an important role in transporting Western Australia a long way on its journey towards becoming a low-waste State.