Mt Ousley interchange – TfNSW issues 'year in review'
As construction work winds up for the year at Mount Ousley interchange, Transport for NSW has issued a progress report on the $390 million project
As construction work winds up for the year at Mount Ousley, Transport for NSW has issued a progress report on the $390 million project.
20 December 2025: TfNSW statement on Mt Ousley interchange
Mount Ousley interchange is starting to come to life with more than 357,000 people hours worked since construction started, and more than one third of the work program now completed.
When complete, the new interchange at the base of Mount Ousley will provide improved connectivity, safety and efficiency on a busy and key corridor for freight and other traffic travelling between Sydney and the South Coast.
Transport for NSW Executive Director Partnerships and Integration South, Cassandra Ffrench, said during 2025 the project team made significant progress on the interchange, with a focus on establishing work areas to allow work to start on the new heavy vehicle safety ramp and the three interchange bridges.
“Bridge piers and retaining walls are now visible for these three new structures that will form the interchange over the M1 Princes Motorway,” she said.
“This year also saw significant progress on the new heavy vehicle safety ramp, and the completion of an upgrade to the pedestrian bridge across the M1 between the University of Wollongong and the TAFE at Northfields Avenue, providing improved accessibility for users.”
Ms Ffrench said next year will see more significant milestones reached with the concrete deck to be poured for the Mount Ousley Road bridge over the heavy vehicle bypass, and the new heavy vehicle safety ramp is set to open.
“Work will also progress to increase the height and width of Mount Ousley Road to meet the new interchange, and work will continue on the new southbound access road to University Avenue,” she said.
“This work will be carried out across four separate 46-hour closures in the first half of the year, designed to reduce impacts to nearby residents and motorists by reducing the duration of night work by nine months.
“We thank the community for their ongoing patience while construction on this important project is carried out.”
Major work started in late 2024 and will take four years to complete, weather permitting.
More information on the Mount Ousley interchange is available at: transport.nsw.gov.au/mountousley.
Motorists are advised the project site is now closed until 6am Monday, 5 January 2026. During this time, there will be no construction work.
The speed limit on the M1 Princes Motorway between Mount Ousley Road and Memorial Drive will return to 80km/h during the close down period. The temporary speed limit of 60km/h will resume during work hours once work restarts on Monday, 5 January 2026.
The interchange looking north and (at right) the view to the east. Images: TfNSW
The project in numbers
- 357,000 people hours worked
- 1150 people inducted into the work site
- 2200 linear metres of bridges piles drilled and poured
- 59 bridge piles poured
- 26,000 cubic metres of earthwork material placed (excluding foundation treatments)
- 1050 tonnes of construction waste reused and recycled
- 93% of electricity used sourced from renewables
- 22 nest boxes installed
- 1430 mm of rainfall in 2025
