Transport and infrastructure engineers have a huge role to play in driving sustainability initiatives that will help Australia stay on track to reach net zero carbon emissions by 2050.
That’s the view of Dennis Walsh, Chief Engineer at Queensland’s Department of Transport and Main Roads (TMR).
Queensland is at the forefront of research into sustainable ways to build and maintain roads, Walsh said, and he is adamant that engineering innovation will continue to be key in helping the sector reach its emissions reduction targets.
“All engineers have a responsibility to do all they can to achieve a greener future,” he said. “Engineers play a key role in implementing and delivering real change.
“We encourage all of TMR’s engineers to proactively look into their own particular disciplines and be curious about how emerging technology can be harnessed to reduce emissions.”
Commitment to sustainability
The Queensland Climate Action Plan includes a range of emissions reduction targets including a 30 per cent cut in carbon dioxide emissions from 2005 levels, and for half the state’s energy to come from renewable sources, both by 2030. The state government has invested more than $10 billion on clean energy since 2015.
With the exception of 2020, transport emissions in Australia have grown every year since 1990, and account for 16 per cent of the country’s total emissions.
“TMR acknowledges this trend and is stepping up to face the challenge,” Walsh said. “Our Environmental Sustainability Policy, released in 2021, is built around the commitment to deliver sustainable and innovative solutions as part of our business practices.
“We are already delivering infrastructure projects using recycled materials such as crumb rubber and recycled glass to reduce landfill, and we’re continually researching and trialling innovative approaches to reduce our emissions. This commitment to research and innovation is helping keep Queensland at the forefront of sustainable infrastructure and delivering real economic benefits.”
Driving innovative practice
Bringing innovations into mainstream practice begins with investigating and facilitating access to sustainable alternatives.
“Established in 2013, TMR’s collaborative research agreement with the Australian Road Research Board, the National Asset Centre of Excellence (NACOE), has been driving innovation in the areas of infrastructure design, asset management and sustainability,” said civil engineer Narelle Dobson, TMR’s NACOE Agreement Manager.
“In the 10 years since NACOE’s inception, the department has been using the outcomes of the research program to introduce sustainability initiatives into TMR’s planning, design, construction and asset management activities.”
The use of waste materials is one area already making a difference. Between 10 and 20 per cent of recycled glass can already be used in roads as a substitute for sand and aggregate. Similarly, fly ash and blast furnace slag (industrial wastes from coal fired power plants and steel production), is able to replace up to 70 per cent of the cement in pavements.
The introduction of fly ash alone can mean a 70 per cent reduction in greenhouse gas emissions in these applications.
Find out more about TMR’s NACOE research program.
A growing trend
The nationwide commitment to sustainability is gaining momentum in the pursuit of net zero emissions.
“Continuous innovation and adoption of better, more climate-friendly solutions are undoubtedly the way forward,” Dobson said. “As engineers, it’s our role to help drive this. That’s why we’re collaborating with our industry partners to research other approaches to decarbonisation.”
Some such approaches are being adopted into standard specifications. They include:
- New types of geopolymer concrete
- Adoption of new pavement materials such as high-modulus asphalt and new approaches to stabilisation
- Changes to asphalt production, including increasing percentages of recycled crumb rubber and reducing production temperatures
- Boosting the types and volume of recycled industrial waste that can be included in a range of materials used in construction
- Encouraging smarter use of locally sourced materials, reducing the distance that construction materials need to be transported
“It’s an exciting time to be an engineer,” Dobson said. “But the climate crisis means it’s also a sobering time. As engineers we need to look at everything we do through a sustainability lens. The community is looking to us to apply sustainable, forward-thinking practices when we undertake our professional work.”