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Project

Tonkin Highway Extension and Thomas Road Upgrade Thomas Road to South Western Highway

Cardup, Darling Downs, Mundijong, Byford, Oakford

Overview

  • Road

    Project type

  • $1 billion More info

    Total budget

  • Under Construction

    Project phase

  • Main Roads WA

    Lead agency

  • 4400

    Jobs supported

  • Mid 2025

    Start date

    Late 2028

    End date

The Tonkin Highway Extension and Thomas Road Upgrade project will transform the south-eastern corridor of Perth by delivering a 14 kilometre extension of Tonkin Highway, and major upgrades to Thomas Road.

The major project supports Western Australia's fast-growing south-east corridor which faces a large volume of traffic to and from the South West and Wheatbelt regions.

The improvements will enhance road safety, reduce travel times, and provide better connections between existing and future residential, business, and employment areas. 

The Tonkin Highway Extension involves the 14 kilometre extension of Tonkin Highway from Thomas Road to South Western Highway as a four-lane dual carriageway.

A Principal Shared Path (PSP) is planned for the full 14 kilometre length and includes five underpasses (Thomas Road and Bishop Road), a footbridge overpass (Orton Road) and local road connections (Copper Road and Adamson Street).

The Thomas Road Upgrade will complement the Tonkin Highway Extension. It includes the widening and 4.5 kilometre duplication of Thomas Road between Kargotich Road and South Western Highway. 

Works include the construction of a new grade separated interchange at Thomas Road and Tonkin Highway, and a new 4.5 kilometre shared path on the south side of Thomas Road.

For detailed project information, visit Main Roads WA.

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Benefits

  • Provide safer and more efficient journeys for more than 60,000 vehicles expected to use the corridor daily.
  • Remove thousands of heavy vehicles off local roads.
  • Deliver new grade-separated interchanges, underpasses and roundabouts to improve traffic flow and safety.
  • Introduce new shared paths for cyclists and pedestrians along the entire extension.
  • Complement the METRONET Byford Rail Extension, enhancing transport choices for the region.

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