Key features of the proposed M4 Smart Motorway

Some individual elements of Smart Motorway technology are already in place on Sydney roads. The M4 Smart Motorway would be the first Smart Motorway for NSW and would bring together all the smart technologies in one place to maximise the performance of the motorway.

Key features

Variable Message Signs on the motorway and approach roads. These electronic signs would inform drivers about expected travel times and traffic conditions ahead, allowing drivers to better plan their journey or choose an alternative route.

Ramp signals on entry ramps to smooth traffic flow onto the motorway. These are quick-change traffic lights that will manage the flow of vehicles entering the motorway. They will make merging safer and easier and reduce the risk of drivers having to brake suddenly. They will operate in peak periods or in heavy traffic.

For more information, read the entry ramp signalling fact sheet.

Lane use signs to open and close lanes in response to incidents.

Variable speed limit signs to vary speed limits if there is heavy traffic, an incident or bad weather.

Additional traffic sensors and CCTV cameras to continually monitor traffic conditions.

Additional emergency telephones and stopping bays to provide drivers with improved safety when their vehicle breaks down or if there is an emergency stop required.

Improvements to interchanges from Mays Hill to Lapstone.

Improvements to 12 interchanges:

  • All entry ramps (except Russell Street westbound) will be realigned, extended and widened to between two and four lanes at the stop line to smooth traffic flow onto the motorway
  • A freight bypass lane will be added to the westbound entry ramps at Prospect Highway and M7 Motorway and the eastbound entry ramp at Roper Road to provide a dedicated entry lane for slow-moving heavy vehicles
  • Some exit ramps will also be realigned, extended and widened to reduce queuing onto the motorway
  • Traffic signalling improvements and minor adjustments will be made at intersections.

View maps of proposed changes for each interchange.

Widening the motorway between the M7 Motorway and Roper Road interchanges to four lanes in each direction to improve traffic flow.

All work is expected to be within the road corridor.

Fact sheets

Read fact sheets about specific impacts of the proposal, including visual amenity, noise and construction impacts.

Share this page: