WestConnex Delivery Authority’s (WDA) objective

To obtain expert technical management capability for one of the largest and most complex infrastructure megaprojects ever undertaken in Australia.


WestConnex is the largest integrated transport and urban revitalisation project in Australia. The project will ultimately link Sydney's west and south-west with the CBD, Airport and Port in a continuous 33km motorway. WestConnex is being delivered in three stages over 10 years, with Stage 3 scheduled for completion in 2023. 

WestConnex Stage 2: M5 is an 11km link between Beverly Hills and St Peters which will duplicate the existing M5 East and extend it towards Sydney Airport.

Johnstaff’s role

Johnstaff was appointed as Technical Manager in the planning and development phase of WestConnex Stage 2, as part of WDA’s integrated project team. The role extended through procurement to delivery. 

Addressing the issues

Johnstaff’s role as Technical Manager involved management of all technical aspects associated with design, specification and procurement of the various M5 works packages. This included the main tunnel works and major road network infrastructure and all associated civil, structural, mechanical and electrical engineering services and systems engineering requirements.

As Technical Manager we delivered all technical components of the tender documentation for the main works contracts and managed the Technical and Environmental consultant teams for WDA, including resolution of all design issues.  

Johnstaff’s role also included expert advice into planning, procurement methodologies and environmental management.

map of the project location


  • Coordination of the large team of design, planning and environmental specialists and their outputs was critical to the success of the highly complex M5 project

  • We brought key design and technical experience as well as lessons learned from previous major government infrastructure projects across NSW and Australia

  • Our team provided added value through its ability to review technical aspects of the project relating to major project financing and potential future asset sales