Melbourne Metro Tunnel Independent Reviewer

AECOM | Australia | 2017-2025

One of the largest capital projects ever undertaken by the State of Victoria

$11 B project cost

Five new underground stations

Twin nine km rail tunnels


  • The magnitude of this high-profile, heavy civil construction undertaking means there are a large number of third-party stakeholders involved and many technical challenges to be solved daily.
  • Providing a collaborative construction review service to multiple parties for the project, providing important guidance and expertise in the construction methods being used.
  • Expertise in construction means & methods, quality management, tunnel design, and their targeted risk-based approach is assisting their clients with the development and improvement of their own systems for obtaining the required deliverables.
  • Focused on facilitating best-for-project outcomes that benefit all parties by taking a highly collaborative and impartial approach to the project.
  • By taking three of the busiest train lines (Cranbourne, Pakenham, and Sunbury) through a new tunnel under the city, the Metro Tunnel will untangle the City Loop so more trains can run across Melbourne on a more frequent basis.


  • Design review services for the bored tunnels and cross-passages.
  • Surveillance and auditing of construction work on the project.
  • Acceptance and certification of the completed works on behalf of the Independent Reviewer.


  • Focusing surveillance resources on excavation works in the Melbourne CBD.
  • The project features tunnel boring machines (TBM) tunnelling in soft and mixed-ground conditions with the use of slurry TBMs.
  • Temporary and permanent structural support systems for trinocular caverns and passenger audits.
  • Use of ground treatment and and ground water recharge systems.
  • Consists of both top down and bottom up construction within an utility congested urban environment.

Project numbers

Project Cost: $11B
$6B Tunnels and stations
$5.2B D&C component
Nine km of bored twin tunnels and five new underground stations.
The twin nine km rail tunnels will be built using four slurry TBMs and 56,000 concrete tunnel lining segments.
Room will be created on the network to enable more than half a million additional passengers per week to travel on the rail network during peak periods.

How we can help you

If you have a problem that needs to be solved, please get in touch.

Contact Us