World first recycled plastic noise walls for Mordialloc Freeway

In a world first, noise walls along the Mordialloc Freeway will be made from 75 per cent recycled plastic collected from households across the state, as part of a drive to build Australia’s greenest freeway.

The 32,000 square metres of noise walls required for the project will be made from more than 570 tonnes of plastic waste, half of which is plastic disposed of in kerbside recycling such as milk and soft drink bottles.

The other half of the recycled content will be made up of soft plastics such as bread bags, food wrappers and bubble wrap, which are notoriously difficult to recycle and usually end up in landfill.

The amount of recycled content going into these noise wall panels is the equivalent of 30 million water bottles, or the plastic waste collected from 25,000 Victorian homes in one year. The noise walls have been made in Carrum Downs by PACT Group, helping them retain local jobs.

This is the first time in the world noise walls have been made from 75 per cent recycled plastic, with the Mordialloc Freeway project exemplifying the principles of the Victorian Government’s Recycled First policy.

Recycled First supports the government’s circular economy strategy, Recycling Victoria, and requires construction companies to demonstrate how they will optimise the use of recycled and reused materials on transport projects.

The implementation of Recycled First is being supported by Ecologiq, an initiative helping to make the state a world leader in the sustainable use of recycled and reused materials. 

Ecologiq has developed new standards and specifications for recycled noise walls, making them easier to replicate on future projects. The Mordialloc Freeway project is a standout example of incorporating green initiatives, including recycled glass in asphalt, recycled concrete in road base and drainage pipes made of recycled plastic.

PACT Group has been able to retain 70 staff at their Viscount Plastics manufacturing site, with 32 panels to be made each workday, and 56 weeks of production required to supply 32,000 square metres of panels. The panels have a lifecycle in excess of 40 years and can be recycled again at the end of their life.

At less than half the weight of steel or concrete panels, the recycled plastic noise wall panels are quicker and safer to install while still meeting or exceeding traffic noise reduction requirements. The recycled plastic panels are also non-porous, meaning paint and graffiti can’t be absorbed into them.

The Mordialloc Freeway is due to be complete by the end of 2021.