In the first post in this series I took a look at the significant differences between Sydney Metro Western Sydney Airport (Metro WSA) which will connect the new airport to the Sydney Trains network at St Marys, and the combined Sydney Metro Northwest and Metro City and Southwest (Metro NW/City/SW) which will run from Tallawong in the northwest to Bankstown in the southwest when it fully opens. I also discussed some of the wide-reaching ramifications of these differences for the development of the metro network.
In part two I’m looking at how the third line under construction, Sydney Metro West (see map below), fits into this picture and canvassing some possible scenarios for the long-term development of Sydney’s metro lines.

Sydney Metro West map (source: Sydney Metro EIS)
First, a quick recap. Metro WSA which is due to open in 2026, will be operated by Parklife Metro, a different consortium to the Metro Trains Sydney group of companies that is operating Metro NW/City/SW, the final stages of which will open in 2024/25. The airport line will use 25 kV AC electrification, unlike Metro NW/City/SW and the suburban and interurban rail networks, which all run on 1,500 V DC. Metro WSA is being constructed to handle three-car trains on opening but the station infrastructure can be expanded to accommodate four cars. This contrasts with Metro NW/City/SW which opened with six-car trains but has been designed to handle eight-car ones.
In part one I concluded that the NSW government obviously wants to ensure that all future rail expansion in Sydney is through metro construction, but is also seeking to avoid a single-operator metro monopoly. In addition the first two metro lines have been designed around their primary purposes, to the point that they will be almost completely incompatible. More significantly, the limited design capacity of Metro WSA will constrain the line’s longer-term future as outer Western Sydney’s key north-south public transport corridor, even if the line is linked to and takes over the Glenfield to Leppington rail link as currently planned.
Given the government has comprehensively separated the operations of Sydney’s first two metros, a third line adds another set of variables. I’ll try to explore some of these and the potential implications, but a word of warning – given that there is limited information about the design parameters for Metro West, especially as the key contracts to develop the stations and to provide, operate and maintain the trains have not yet been let, the following commentary is fairly speculative.