Tonkin Highway Extension and Thomas Road Upgrade

Overview

Road
Project type
$1 billion
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.

Benefits

Enhanced traffic flow and travel times.
Improved road safety for all road users.
Improved freight efficiency, connectivity and travel time.
Reduced pressure on surrounding roads.

Gallery

Artist's impression of the Orton Road development, which will include a roundabout, five underpasses and a footbridge.

Artist's impression of the Orton Road development, which will include a roundabout, five underpasses and a footbridge.
Artist's impression of the grade-separated interchange at Bishop Road to improve traffic flow and safety.

Artist's impression of the grade-separated interchange at Bishop Road to improve traffic flow and safety.
Artist's impression of Tonkin Highway to South Western Highway.

Artist's impression of Tonkin Highway to South Western Highway.
Artist's impression of the Tonkin Highway Extension and Thomas Road Upgrade at night time.

Artist's impression of the Tonkin Highway Extension and Thomas Road Upgrade at night time.
Video: Tonkin Highway Extension and Thomas Road Duplication Project visualisation (November 2023).

Video: Tonkin Highway Extension and Thomas Road Duplication Project visualisation (November 2023).
Planned works include a 14km extension of Tonkin Highway from Thomas Road to South Western Highway as a four-lane dual carriageway.

Planned works include a 14km extension of Tonkin Highway from Thomas Road to South Western Highway as a four-lane dual carriageway.

Project map

This map shows an aerial view of the project location. Turn on the toggle below to show disruptions.

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Detour options

Tonkin Highway PSP Closure - From 15 September until Late 2028

The Tonkin Highway Principal Shared Path (PSP) will close between south of Rowley Road and Thomas Road from Monday, 15 September 2025 until project completion. Path users are encouraged to use the existing PSP network at Armadale Road or find an alternative route. See Main Roads Travel Map for the most up-to-date information.

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Hopkinson Road Permanent Closure - From 15 September 2025

From Monday 15 September 2025, Hopkinson Road between Thomas Road and Jersey Road will permanently close. This closure is required to construct the temporary Thomas Road realignment, allowing vehicle movements along Thomas Road as permanent construction starts in late 2025. See Main Roads Travel Map for the most up-to-date information.

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