Even the tough surface of our roads is not immune to the challenges of climate change.
The House of Representatives Inquiry into the implications of severe weather events on the national regional, rural, and remote road network released a report in December 2023 that has put road damage in the spotlight and found that science needs to be part of the answer.
“The increasingly severe and intense weather events over recent years, particularly the 2022 and 2023 floods across Australia, have taken a tremendous toll on our road network and our nation,” Standing Committee on Regional Development, Infrastructure and Transport chair Luke Gosling said.
“The unprecedented scale and intensity of floods, torrential downpours, and bushfires have caused catastrophic damage to our road infrastructure, exposing its vulnerability against severe weather events and a changing climate.”
The Australian Local Government Association (ALGA) has estimated recent severe weather events across New South Wales, Queensland and Victoria alone have caused more than $3.8 billion in damage to road and road-related infrastructure.
And it’s only going to get worse.
GrainGrowers Acting General Manager Policy and Advocacy Sean Cole said the impact of climate change on the road network “could not be underestimated”.
“With climate change expected to increase the frequency and intensity of weather events such as heat waves, floods, and extreme temperatures, it is vital all levels of government work together to strengthen Australia’s long-term road resilience.”
The report found the national road infrastructure – “the lifeblood of our communities, particularly across regional, rural, and remote areas” – was plagued by maintenance underinvestment and backlogs, asset condition data gaps, challenges accessing betterment funding, and “a lack of cross-government collaboration and planning to support targeted investment and risk mitigation”.
It noted severe weather events had brought the problems associated with a sub-standard and “dangerous” road network to the surface.
Among the recommendations made by the parliamentary inquiry was a greater partnership between levels of government, industry – and scientists.
Roads Australia told the inquiry the industry was at “the confluence of climate, carbon reduction and resilience”.
“We have to step back from practices we’ve used over the last 30 or 40 years,” the inquiry report quotes Roads Australia as saying.
“We have to consider the new landscape that we operate in, which is one that is affected by climate, one that is affected by 2030 and 2050, and our desire to be carbon neutral, and one that actually demands that we look at our infrastructure in completely different ways”.
The committee recommended government, industry and the scientific community look at innovative and recycled technologies and the identification of corridors that are more “climate resilient”.
Among the technologies touted in submissions were: a Victorian-developed asphalt mix composed of recycled glass, plastic and reclaimed asphalt; foamed bitumen; crumb rubber added to bitumen seals; and the Intelligent Compaction Technology (ICT) system where a plant’s existing rollers are fitted with a GPS, a measuring sensor, and display screens to provide real-time feedback on the level of compaction.
“Adaptation to climate change in transport infrastructure should be planned for the life of the infrastructure,” the Australian Local Government Association submission argues.
“If we expect a bridge or railroad to last 100 years, then it should be designed to operate safely in the climate range forecast in 100 years’ time.”
Among ALGA’s suggestions are designing roads to allow for greater extremes in temperatures through thermal expansion, heat degradation and passenger comfort.
It also recommends a better micro-climate in urban works through shade and breeze corridors, designing with rising sea levels and storm surges in mind, and planning ahead for events such as bushfires, cyclones and floods.
The committee has backed similar suggestions with a recommendation for all levels of government to work together, and with the scientific community and industry to update national road infrastructure design and construction standards.
The new standards would allow for measures including resilience, new engineering and design principles, innovative and recycling technologies to future-proof the country’s roads.
The report will now be considered by the Federal Government.
The Greenlight Project is a year-long look at how regional Australia is preparing for and adapting to climate change.