Building work on the refit of Heysen Tunnels has been completed on schedule, with new systems and equipment now in place ahead of final testing, marking the end of ongoing traffic restrictions.
The upgrade addresses tunnel elements that were at the end of their service life after over two decades of use. It also improves safety, along with traffic management and incident response capabilities.
The Heysen Tunnels were first opened in March 2000 and provide a high-speed dual carriageway between Adelaide, the south-east of South Australia and the eastern states. Although constructed to the highest standard at the time, Australian and international standards relating to road tunnel safety have developed significantly since then, so the upgrade has brought this important infrastructure up to current standards.
Project works (seen here) include:
- upgrading the tunnel lighting system to a new LED configuration
- installing a new automated fire suppression system
- upgrading the tunnel ventilation system
- repairing the tunnel lining and installing monitoring equipment
- upgrading the Intelligent Transport System equipment, including thermal incident detection systems, new and replacement CCTV, Lane Use Management Signs, Variable Message Signage and over height vehicle detection
- upgrading the traffic management system to restrict access to the tunnels in the event of an emergency incident, and
- upgrading the emergency communication systems, including public address, radio rebroadcast, in-tunnel signage and help phones to improve safety and network reliability.
The Australian and South Australian governments committed $150 million (80:20) to deliver the Heysen Tunnels Refit and Safety Upgrade, as part of the broader South Eastern Freeway Upgrade.
Among the more noticeable upgrades are the new exhaust fans - eight in the Crafers-bound tunnel and 15 in the Adelaide-bound tunnel.
These 'Half-Banana Jet Fans' form part of the tunnels' fire suppression system to disperse smoke in the event of an incident. They will also provide ventilation, control exhaust fumes and clear any fog in the tunnel. The Adelaide-bound tunnel requires a greater number of fans to allow for smoke or fog to be pushed downhill ahead of any traffic. The term 'Half-Banana' refers to the slight bend in the fans, to direct airflow along the curved roof of the tunnels.
The project has also seen the installation of
- over 1,000 LED lights
- 6 overhead gantries
- over 140 CCTV and incident detection cameras
- a pair of 400 kL water tanks
- 60 km of cabling.
Final system testing will continue into early 2025, with advice around temporary traffic restrictions to be provided appropriately. Some temporary traffic controls will occur during this period, with January traditionally the quietest time of the year for traffic through the tunnels. Testing will not impact the 2025 Tour Down Under.
As put by Tom Koutsantonis
These tunnels have been in operation for a quarter of a century now, and this upgrade will see them operating at the top of their game for many more years to come.
Thank you to freeway users for their patience to date. I know it was frustrating but doing the majority of the work out of peak hours meant we could avoid prolonged and disruptive closures of the tunnels.
I am pleased that all items have now been installed, with final testing underway. We'll continue to keep tabs to make sure all the new elements are working correctly.
Of course we hope we don't need to use the tunnels' emergency management equipment, but it is reassuring to know that in the event of an emergency we have the best available equipment fitted and ready to go.
As put by Member for Kavel Dan Cregan
It's great to see these important safety works coming to an end.
As a Hills motorist, I'm also thrilled the tunnels will be open again without traffic restrictions in place.
