Picton Road and M31 Hume Motorway - Picton Road upgrade


Project overview

Transport for NSW is planning to upgrade Picton Road between the Nepean River and the M1 Princes Motorway, including the interchanges at the M31 Hume Motorway and the M1 Princes Motorway. The upgrade has been divided into three project areas, western, central and eastern.

The western section of the Picton Road upgrade is between the Nepean River and Almond Street in Wilton including the M31 Hume Motorway interchange.  

The section involves: 

  • Widening and upgrading approximately 5 kilometres of Picton Road between the Nepean River and Almond Street in Wilton.
  • Upgrading the existing Picton Road and M31 Hume Motorway interchange into a diverging diamond layout. 

Watch an animation to see how a Diverging Diamond Interchange (DDI) could work.

Artist impression of a Diverging Diamond Interchange at the Picton Road and M31 Hume Motorway intersection.


Community information

Community notifications


Frequently asked questions (FAQs)

  • What is a Diverging Diamond interchange?
    A Diverging Diamond Interchange (DDI) allows two directions of traffic to temporarily cross to the left side of the road. It moves high volumes of traffic through an intersection without increasing the number of lanes and traffic lights. It is easy to navigate, eliminates last-minute lane changes, and provides better sight distance at turns. The design reduces congestion and moves high volumes of traffic without the need to increase the number of lanes in an interchange.
  • Why is it innovative?

    DDIs are a relatively new concept in Australia and the design innovation is that it allows free flowing turns when exiting and entering Picton Road with right-turning traffic does not have to give way to opposing traffic.

    The Picton Road and M31 Hume Motorway DDI is the second to be proposed in NSW, with one currently proposed for Australia Avenue, Homebush and three DDIs now operational in Queensland.

  • Why is the DDI the preferred option for the interchange?
    In response to feedback, we have developed a DDI as the preferred option for the interchange at Picton Road and the M31 Hume Motorway because it provided the least impact to the surrounding area while improving safety, reliability and efficient travel when compared to other options.

  • What other options were considered?
    A technical assessment of the design, standards, and specifications of DDIs across Australia and around the world was carried out as part of the selection and design development process.

    We assessed 13 different options for the interchange. Options included double roundabouts, grade separated roundabouts, a four-way signalised intersection with and without a bridge, grade separated ramps, loop interchanges and continuous interchanges with loops. We identified an intersection with traffic lights, configured as a DDI, was the best outcome when compared with other options.

  • How does it improve safety?
    The DDI design would allow free flowing turns when exiting and entering Picton Road and reduce the number of conflicts with oncoming traffic, resulting in fewer traffic light phases, making the interchange safer and more efficient.

  • When is construction expected to start?
    Timing and funding for construction of the interchange are yet to be confirmed.

  • What happens next?
    A concept design will be developed, and further environmental studies will be carried out. The REF will be displayed in 2024.

  • Why was the project divided into sections?
    We have divided the upgrade into three project areas to ensure we can focus on the areas you told us to prioritise while allowing us to continue concurrent planning for all sections.

  • Where is the western section of Picton Road?
    The western section of the Picton Road upgrade is between the Nepean River and Almond Street, Wilton and includes the Picton Road and M31 Hume Motorway interchange.

  • What are the other sections?
    The central section begins at Almond Street, Wilton to around Mount Keira Road, and the eastern section runs from around Mount Keira Road to the M1 Princes Motorway interchange.

  • Why is the interchange being given priority over other sections?
    Safety is the number one consideration as we progress the Picton Road upgrade.

    Feedback told us Picton Road and the M31 Hume Motorway interchange was of particular concern, with access to and from the interchange considered a significant issue.

    There are delays, congestion and frustration for those using the interchange contributing to less reliable and safe access to and from Picton Road. As traffic, development and population continue to grow, we must be able to accommodate more traffic through the interchange.

Contact us

For further information about this project, please contact:

Phone: 1800 290 613

Email: pictonroad@transport.nsw.gov.au

Mail: Picton Road upgrade, PO Box 477, Wollongong NSW 2520