Tonkin Highway Extension and Thomas Road Upgrade | Proposed Thoroughfare Changes

Published on Thursday, 2 October 2025 at 3:55:11 PM

 Hopkinson Road, between Cavanagh Close and Gossage Road, and Gossage Road at the intersection with Hopkinson Road will be closed to traffic from 3 November

In accordance with section 3.50 of the Local Government Act 1995, notice is hereby given that the Shire of Serpentine Jarrahdale is required to make thoroughfare changes to:

• Hopkinson Road, between Cavanagh Close and Gossage Road; and
• Gossage Road at the intersection of Hopkinson Road.

These changes will take effect from 3 November 2025 as part of the Tonkin Highway Extension and Thomas Road Upgrade (THETRU) Project.

Project Overview

As part of the THETRU Project, Tonkin Highway is being extended 14 kilometres from Thomas Road to South Western Highway as a four-lane dual carriageway. The new Tonkin Highway will cross over Hopkinson Road and Gossage Road.

To enable permanent construction of the highway:

• Hopkinson Road will be closed to vehicle traffic between Cavanagh Close and Gossage Road; and
• Gossage Road will become a cul-de-sac at the Hopkinson Road intersection in early November.

These changes are required in early November 2025, to support the highway construction and associated haulage operations.

These thoroughfare changes are intended to:

• Support permanent construction of the highway extension crossing over Hopkinson Road and the Gossage Road equine and pedestrian underpass;
• Enhance road safety during and after construction; and
• Allow for the haulage track to be built within the project boundary, limiting the number of trucks on local roads and reducing interface with construction traffic.

The project is working closely with the Shire of Serpentine Jarrahdale and the Department of Fire and Emergency Services (DFES) to ensure emergency access routes are maintained during construction and are incorporated into the final road design. Bushfire safety and emergency response are key considerations in the planning process.

Inspection of Plans

Plans detailing the proposed closures and new access routes can be seen below or online at www.sjshire.wa.gov.au.

Map: Hopkinson Road and Gossage Road closures and alternate access routes

Submissions

Written submissions or feedback regarding the proposed closures may be submitted to the Shire by 5pm, 24 October 2025.

Submissions should be addressed to:

Chief Executive Officer
Shire of Serpentine Jarrahdale
6 Paterson Street, Mundijong WA 6123
Email: info@sjshire.wa.gov.au

For further information, please contact the Shire on (08) 9526 1111 or email info@sjshire.wa.gov.au.

Permanent thoroughfare changes

As part of the Tonkin Highway Extension and Thomas Road Upgrade, several permanent thoroughfare changes will be required. The planned timings are listed below but may change depending on the construction schedule. Public notices will be provided ahead of each closure. In some cases, road naming changes will also be needed, and these will be communicated directly to affected residents.