Kariong to Somersby – M1 Pacific Motorway upgrade

Roads and Maritime Services is upgrading the M1 Pacific Motorway between the Kariong and Somersby interchanges to improve traffic flow and safety. The upgrade involves widening the motorway and upgrading three of the four ramps at the Kariong Interchange.

Updates and announcements

Work on the upgrade is expected to start in mid-2017. Roads and Maritime will provide more information to residents and stakeholders as the project progresses.

Project background

The M1 Pacific Motorway is a critical link in the National Land Transport Network and is part of the Sydney to Brisbane corridor, which is one of the busiest transport corridors in Australia.

The eight kilometre section of motorway between the Kariong and Somersby interchanges is a combination of two or three lanes in each direction. It is used by through traffic, including long haul freight, as well as traffic accessing the Central Coast.

The upgrade from Kariong Interchange to Somersby Interchange will cater for the expected increase in traffic forecast as a result of predicted growth in the Central Coast, Hunter Region and North Coast, along with greater freight demand.

Under a contract awarded to Arcadis (formerly Hyder Consulting) in 2015, detailed design is underway and construction is expected to start in 2017.

The M1 Upgrade Kariong to Somersby project is part of the M1 Pacific Motorway Productivity Package. The M1 Productivity Package is valued at about $400 million and is funded by the Australian and NSW Governments, with the Australian Government contribution capped at $195.8 million.

Other projects included in the M1 Productivity Package are:

  • M1 Upgrade Tuggerah to Doyalson; and
  • Upgrade of the intersection of M1 Motorway, Weakleys Drive and John Renshaw Drive at Beresfield.

Key features and benefits

Work will include:

  • Repairing sections of the concrete motorway between the Kariong and Somersby interchanges to facilitate construction of an additional lane
  • Widening the motorway between the Kariong and Somersby interchanges to provide three lanes in each direction.

The project excludes the section of motorway between the north-facing and south-facing ramps at Kariong Interchange. Traffic modelling and predicted traffic volumes for this section of motorway show that the existing arrangement meets capacity requirements now and into the future.

The project also includes upgrading three of the four ramps at the Kariong Interchange to increase capacity and safety for merging traffic, including:

  • Upgrading and extending the southbound entry ramp lanes (to Sydney) to two lanes
  • Upgrading and extending the northbound exit ramp (to Gosford) to two lanes
  • Extending the northbound entry ramp (to Newcastle) and upgrading the northbound entry ramp intersection with Wisemans Ferry Road.

Key benefits will include increased traffic capacity along the motorway for more reliable travel times, and improved capacity and safety at the Kariong Interchange ramps.

Next steps

Work on the upgrade is expected to start in 2017 with completion in 2019, weather permitting.

Roads and Maritime will continue to keep stakeholders and the community informed as the project progresses.

Share this page: