Northconnex is a nine kilometre tunnel that will link the M1 Pacific Motorway at Wahroonga to the Hills M2 Motorway at West Pennant Hills, removing around 5,000 trucks off Pennant Hills Road each day. It will be the longest road tunnel project in Australia.
Fire and Rescue NSW has been consulted in the development of the tunnel design and the associated fire, life and safety systems. The tunnel design is to be aligned with the current Australian and international standards and minimise the likelihood of incidents. Incidents for the project are managed in collaboration with the Transport Management Centre to ensure a smooth construction process.
NorthConnex Tunnel Design
The tunnel design includes one tunnel for traffic in each direction. This reduces the chance of a head-on collision and increases operational safety. The tunnel is built for three lanes, operating as two lanes with a future working lane for any foreseeable growth. Dangerous goods and overweight vehicles will not be permitted in the tunnels and will still have to use the overhead roads. By comparison to the M2 tunnel presently has the highest clearance in Sydney at around 5.1 m and so far has no overheight incidents. Most tunnels in Sydney have a clearance of 4.6m.
Safety Features of the Tunnel include:
- State-of-the-art CCTV with automatic incident detection throughout the tunnel
- An audible system (PA) to help manage incidents
- Height detection system before tunnel entry points to activate illuminated warning signs
- Pedestrian cross passages between main alignment carriageways at intervals of 120 metres
- Wide road shoulders to accommodate breakdowns and access by recovery and emergency vehicles
- Emergency telephones for motorist use at intervals of 60 metres and in all cross passage refuges
What are the implications in the case of an incident?
If an incident has already occurred, drivers of the vehicle would be encouraged to continue out of the tunnel. If the vehicle is yet to reach the incident the drivers would be asked to stay inside unless it is an emergency scenario. Drivers/occupants would then be directed to the nearest emergency pedestrian exit or through a cross passage in the opposite direction.
The tunnel is forecasted to be equipped with access to gates to prevent vehicles from entering during the case of an incident. The VMS outside the tunnel will alert the passing vehicles that the tunnel is closed.
Incident Management Features in the NorthConnex
- Continuously manned motorway control centre to respond to emergency circumstances
- Automatic fire and smoke detection within tunnels
- Deluge system – activated automatically at the fire source (can also be activated manually)
- Emergency pedestrian exits from the main tunnels and entry and exit ramps
- Traffic variable message signage (VMS)
Learn about other tunnel projects in depth at the 7th Annual Tunnel Operations and Maintenance Conference running 20th to 21st February 2019 in Sydney. Take valuable international lessons from Sallo Van Der Woude, member of the Dutch Tunneling Association & Project Manager at Van Hattum en Blankevoort who will be speaking on operating & renovating tunnels in the Netherlands infrastructure network.