#20 Smart Traffic Technology

Recommendation #40 in Victoria’s draft 30-year infrastructure strategy 2025-2055 promotes increased use of modern traffic control technology for efficient and safe journeys. Technology such as sensors and cameras provide data to road management authorities to optimise traffic signal sequencing, provide information to road users through dynamic/variable messaging, and improve traffic flow. Incident response services also use such technology for incident identification and management. Cameras, sensors and variable message signs are key technological features of ‘smart motorways’ in an intelligent transport system. However, full use of the technology is currently limited to a small number of roads in Victoria, such as Melbourne’s Monash Freeway. Extending the technology to additional motorways and arterial roads over time is expected to reduce travel times and increase safety through improved congestion management.

Proven benefits

Research shows that smart technology upgrades on the Monash Freeway have increased speeds by up to 28% while reducing the crash rate by a similar percentage of 30%. Application of variable speed limits (VSL) helps to achieve these outcomes, with US research attributing 34% total crash reductions to this specific measure. As well as congestion management and incident response, VSL is used in work zone speed management and inclement weather scenarios.

While expensive and time-consuming to implement across an entire network, Victorian modelling indicates a benefit-cost ratio of up to 14:1 per dollar invested in smart traffic control technology. US research suggests ratios of up to 40:1 are achievable with implementation of VSL.

Health and environmental benefits

Traditional responses to increased demand, and subsequently congestion, are to build new roads and/or increase the capacity of existing roads (e.g., by adding lanes). However, this approach generally soon leads to increased traffic volumes (demand) and does not alleviate congestion problems in the long term. Associated construction activities often lead to major traffic and environmental disruptions, increased crash risk, and commitment of extensive resources. Efficient management through smart technology is recognised as providing better value, which according to the draft 30-year strategy ‘can be delivered for under a third of the cost of major road projects’.