Lithgow, New South Wales


Transport for NSW 



  • Roads


 2014 – 2017

Contract value

$100 – 150 million

Great Western Highway: Hartley Valley to Forty Bends

Fast facts

10,000 vpd

vehicles per day use the highway including heavy traffic

13 km

of highway reconstruction realignment and widening

90,000 t

of asphalt used in the upgrade

18 m

high concrete and reinforced earth retaining walls

21 no.

trainees and apprentices employed (target of 5)


in savings for one of the retaining walls


This Great Western Highway project entailed reconstruction, realignment and widening a 13 km section to improve safety and traffic flow for the daily 10,000 vehicles that use this busy Sydney to central west NSW commuter, freight and tourist route.

The scope involved enhancing the existing highway by upgrading 5 intersections, improving road surfaces and changing the horizontal and vertical alignment to improve overall safety. Further safety enhancements included:

  • an innovative arch structure over Whites Creek to reduce the risk of black ice formation at the foot of the Blue Mountains near Lithgow
  • a new road geometry – as well as improved superelevation and sight lines – designed to modern standards
  • more consistent intersection treatments with dedicated turning lanes
  • additional arrows and reflective markers to provide clear definition of lanes
  • wider road shoulders with improved drainage
  • installation of concrete and wire rope safety barriers.

The project included upgrading underground utility services, working near heritage-protected structures and maintaining their integrity, batter stabilisation work, constructing retaining walls, fauna crossings, rigid concrete pavement works, and an eastbound downhill overtaking lane on River Lett Hill.

Seymour Whyte delivered the project in stages to provide these improvements while reducing the overall impact of construction on the community.

“Just wanted to say how professional you and your team and TfNSW were last night. The people were really happy with your approach and how you all engaged with them.  They felt listened to and comments after you all left were really positive. So well done last night and also well done during the course of the last 12 months in sorting through some issues with local residents. As you’d appreciate the local community went through a long period of input into various upgrade options and in some cases, things got a bit heated between TfNSW and some locals. But it was refreshing last night to see the positive engagement.  Could you pass our thanks onto your team and TfNSW”

Renzo Benedet, local resident, Jun 2016

Project gallery


Slide 1

Innovation: Arch over Whites Creek

Slide 2

Power of Engineering Inc. site visit for high school girls

Slide 3

View of Great Western Highway at South Bowenfels from Hassans Wall

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