Sydney Metro West, an underground rail megaproject valued at approximately $19 billion, entered a major implementation phase late last month after Sydney Metro signed four major contracts for stations, tracks and systems, trains and long-term operations.
The signing of the contract on 29 December 2025 marks the project’s transition from predominantly linear tunnel work to station construction, system installation and long-term operations planning, amplifying construction activity as multiple complex work fronts progress simultaneously.
Construction of the underground network, almost two decades in the making, finally began in 2022 after years of planning, obtaining the required environmental approvals and conducting geotechnical investigations.
Early works and large tunnel packages laid the physical backbone of the 24km underground line linking Parramatta, the city’s second largest commercial centre, with Sydney’s central business district (CBD).
The scope of the project includes double tunnels, roundabouts, new metro stations and supporting infrastructure, with an opening scheduled for 2032, according to documents reviewed by ENR.
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Under new deals, John Holland, an Australian contractor, won the Linewide package worth about $2.2 billion. It includes the installation of 60 km of track, power, communications, ventilation, fire systems and the construction of a 38-hectare stabling and maintenance facility at Clyde, an industrial rail site near Parramatta.
The Stations West package, valued at around $1.9 billion, was awarded to Malaysia-based tunneling and infrastructure contractor Gamuda Berhad for the design and construction of five new metro stations at Westmead, North Strathfield, Burwood North, Five Dock and The Bays.
Highlighting the role these stations will play in the wider network, New South Wales Transport Minister John Graham said: “The new interchange links at Westmead and North Strathfield will allow Metro passengers to connect directly to the Sydney Trains service, strengthening the wider transport network.”
A contract for trains, systems, maintenance and operations worth approximately $2.7 billion was awarded to the Metro Trains West consortium, led by MTR Corp. with CRRC Corp. The 22-year contract covers the acquisition and commissioning of the trains, operations and maintenance of the system.
Sydney Metro also appointed the Metropolis consortium, led by Lendlease with Mirvac and Coombes Property Group, as the precinct development partner for Hunter Street Station. This package, valued at around $1 billion, includes the delivery of the metro station and two over-station commercial developments in the CBD.
An aerial view of Sydney’s central business district shows the Hunter Street precinct, where Sydney Metro West will provide a major metro station and superior retail development designed to anchor the line’s main CBD interchange.
Photo courtesy of Sydney Metro West
Hunter Street is planned as the main CBD gateway and interchange for the Western Line, providing direct connections to various existing Sydney Metro trains and services under the city’s busiest shopping district.
Project documents describe the station as a high-capacity node designed to handle peak passenger flows while allowing return operations at the end of the line, a combination that concentrates both operational importance and construction risk within a tightly constrained underground footprint.
Together, the four contracts total between $7.6 billion and $7.8 billion, representing the largest tranche of awards since the tunneling project began.
Project documents identify Westmead station, a deep underground stop in a dense medical and educational precinct, as representative of the engineering complexity expected at several stations.
Crews recently finished installing what the state described as the largest formwork arch in the southern hemisphere — a 69-foot-wide temporary structure that supports the excavation of the cavern, followed by an 82-hour hoisting and winching operation and a 1,941-ton concrete pour forming cavern walls up to 8 feet thick.
Terrain conditions Shape delivery strategy
Environmental approvals and hydrogeology assessments show that Sydney Metro West is being shaped by both subsurface conditions and alignment geometry. The corridor is dominated by Ashfield Shale, with deeper sections of Hawkesbury Sandstone and localized areas of alluvium and altered fill near river crossings and former industrial sites.
Groundwater is shallow along much of the alignment, with regulatory approvals requiring active dewatering and continuous monitoring linked to trigger ground movement thresholds. In some locations, the station’s caverns are expected to remain open for up to two years, increasing reliance on stage excavation, temporary ground support systems and real-time instrumentation.
These constraints are most acute at Hunter Street, where the station caverns and return are planned below a dense high-rise development and close to existing underground rail assets. Planning documents highlight tight clearances and conservative movement limits, requiring carefully sequenced excavation and continuous monitoring to protect adjacent structures.
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Construction prospects
Sydney Metro has said the tunnel through the corridor is due to be completed by 2026, with station construction, tunnel retrofitting and systems installation accelerating from 2027 as newly signed contracts progress. Additional contracts for Parramatta, Sydney Olympic Park and Pyrmont stations are expected to be announced later this year.
With formally executed delivery contracts and underground work technically demanding the expansion, Sydney Metro West is among the world’s largest publicly funded active urban rail projects. For contractors and engineers, the project illustrates how geology, groundwater management and dense urban interfaces increasingly define delivery risk as we transition from megaprojects to station construction, system integration and long-term operations.
Sydney Metro Chief Executive Peter Regan said the contract signing positions the program for a sustained increase in activity, adding: “With these landmark signs, Sydney Metro West is poised for a busy and exciting 2026.”
