Tonkin Highway Extension

Thomas Road to South Western Highway

In planningFuture

Extend Tonkin Highway an additional 14 kilometres.

Tonkin Highway intersection

What's happening

 Road safety star rating

An Australian Road Assessment Program (AusRAP) assessment was recently undertaken for the project, with Star Ratings awarded based on its level of safety. The assessment was led by Main Roads in collaboration with Arup and iRAP/AusRAP.

The project achieved a fantastic result:

  • 5 stars for active transport (pedestrians and cyclists)
  • 4 stars for vehicles
  • 3 stars for motorcyclists (due to highway’s higher speed limit)

AusRAP provides independent information and advice about the safety of our major highways and identifies measures to improve safety, and reduce road trauma (road fatalities and serious injury).

 Heritage Interpretation Study

The project is conducting a Heritage Interpretation Study, to identify and explore key Traditional Landowner and European history opportunities that can be incorporated within the Urban Landscape and Design Framework. A significant component of this is Traditional Landowner liaison. As part of this liaison, the project team (and heritage consultant Element) have conducted a storytelling workshop with Aboriginal Elders, looking at the Aboriginal and historic heritage site locations, opportunities for interpretation and developing a vision for the project.

 Development activities

Development work is wrapping up in 2023, including concept design finalisation, environmental and heritage approvals, land requirements, rail authority liaisons, service relocation consultations, existing pavement investigations, geotechnical works, access and connectivity strategy, fire and emergency entry/egress provisions, noise wall and visual screening assessments, and a visualisation.

Upcoming work includes finalising the construction procurement strategy and timings in partnership with industry.

 Sustainability excellence

The project’s planning recently achieved a ‘Bronze’ Rating under the Infrastructure Sustainability Council Infrastructure Sustainability (IS) Rating Scheme, with a score of 27.2 points across 16 credits. The credits included Urban and Landscape Design, Resilience, Climate Change, Resource Efficiency, and Stakeholder Engagement.

The Bronze rating recognises the joint efforts of the Main Roads and Arup project teams’ to plan for best practice outcomes in sustainability. Main Roads and Arup jointly submitted the Tonkin Highway Extension project for nomination for the Infrastructure Sustainability Council’s (ISC) Annual Award and were shortlisted as finalists for the Award.

The Bronze rating will set the Delivery team up to achieve the mandated Silver ISC rating for the design and construction phase of the project.



pressure on surrounding roads


travel times


road connectivity

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Acknowledgement of country

The Government of Western Australia acknowledges the traditional custodians throughout Western Australia and their continuing connection to the land, waters and community. We pay our respects to all members of the Aboriginal communities and their cultures; and to Elders both past and present.

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