Mount Ousley safety and reliability improvements

The have your say consultation seeking feedback on experiences travelling along and accessing this section of the motorway has now closed.

We’d like to thank the community and stakeholders for providing their feedback.

Feedback received during the consultation period will be considered as we plan for improvements to this section of the motorway. A summary of feedback received will be shared with the community.

To learn more about the Mount Ousley safety and reliability improvements project view the September community update (PDF, 4.77 MB).  

The Mount Ousley safety and reliability improvements project will explore a five-kilometre section of the M1 Princes Motorway between Picton Road and the Mount Ousley interchange at the base of Mount Ousley.

The project is currently in the early stages of investigating options to improve the safety, reliability and resilience of this section of the motorway.

The M1 Princes Motorway in this location forms part of the key corridor for movement of freight between the Illawarra region and Greater Metropolitan Sydney via the Princes and Hume Highways (via Picton Road). It is the only crossing of the Illawarra escarpment suitable for higher productivity freight vehicles, with alternative routes subject to load limits and other restrictions.

This section of the motorway through Mount Pleasant and Mount Ousley carries about 55,000 vehicles per day and is currently subject to traffic congestion, particularly during weekday peak periods and weekend/holiday peaks. The steep road grades and road geometry, variable posted speeds for heavy and light vehicles, and capacity constraints all combine to generate significant vehicle movements which impact road safety and the ability to respond efficiently to unplanned incidents. The challenging topography and high traffic volumes result in regular planned closures of this section of the motorway for routine maintenance.

• Mount Ousley safety and reliability improvements location map – September 2025 (PDF, 3.79 MB)

Where is the project up to?

The project is currently in the early stages of investigating options to improve the safety, reliability and resilience of this section of the motorway.

A have your say consultation period was open between 22 September and 20 October 2025. During this consultation period Transport sought feedback on experiences travelling along and accessing this section of the motorway. Feedback received during the consultation period will be considered as we plan for improvements. A summary of feedback received will be shared with the community.

We will be carrying out field investigations from October 2025 to also support the planning and development of options. 

What field investigations will be carried out?

The project is carrying out field investigations from October 2025. These may include:

• Aboriginal heritage and cultural values investigations
• biodiversity studies to identify plant and animal species and communities
• traffic studies and traffic counts
• ground survey, utility and geotechnical investigations
• other environmental investigations

This will help us develop options that minimise impacts to the community and environment as much as possible.

Field investigations will largely be carried out within the road corridor however some studies will need to be carried out on private properties.

What are the benefits of this project?

The project aims to identify measures to:

• improve safety for all road users
• improve traffic performance and reliability
• enable effective operations management for maintenance, roadside assistance and incident response
• strengthen the freight network’s resilience.  

How much funding is allocated to this?

The NSW and Australian governments have jointly committed $10 million towards planning options to improve the safety and reliability of this section of the motorway. Funding for delivery of improvements will be sought after the planning is complete. 

• September 2025 community update (PDF, 4.77 MB)
  Mount Ousley safety and reliability improvements community update