In part one, I concluded that the growth in express running has outpaced the growth in trip length, and that this was done more or less to make rail more more competitive with the private car.
Has it been the best way make rail competitive though? The DoI thinks so, and contend that “express trains are a highly valued part of the metropolitan train timetable”.
The problem is that express trains are very path hungry when they have to share the same tracks as trains which stop all stations. So unless there’s more than two tracks, line capacity – and consequently frequency – is lowered. This isn’t just a problem for stations which are expressed, it reduces capacity for the whole line.
Of the 430 km of rail lines in Melbourne, 335 km are double track, 65 km are single track, and only 30 km are triple track or better. This means that on 78% of the network, there is a significant trade off between frequency and express running, and that 15% of the network (the single track bit) can’t handle either frequent or express services.
The DoI knows this, but claims that while “Reducing the number of express trains would help to increase capacity, but would significantly increase travel times from the outer suburbs and may dissuade commuters from using the train at all.” Really? In Melbourne, the rule of thumb is that every station expressed will save 1 minute compared to if the train called at the station. But you need to run sweeper services in between the expresses to serve the stations which are expressed. So, on the 78% of Melbourne’s network that is double track, every station expressed brings you 1 minute closer to the stopper in front, reducing the headway. Of course, stopping all stations trains can come in behind the expresses at whatever the signal headway is.
The upshot of this is that express running will increase average wait time on double track rail. Given that total travel time = time on train + wait time + walk to and from stations, the benefits of express running are mitigated. For more information on this, have a look at Riccardo’s training track page on true end to end journey time. Furthermore, we need to remember that lower frequency means lower capacity, meaning that the line can transport fewer passengers.
I’m not saying express running is bad per se, but rather that we need to be aware of the costs and benefits. Often, express services are a good idea, but generally on long, busy lines with the infrastructure (preferably 4 tracks) to support frequent services. I should note that where some express running is fixed into the timetable (like V/Line trains in Melbourne) then metropolitan expresses may be easier.
Consequences for Melbourne
There is a case for express running on parts of the Melbourne rail system. If expresses are needed anywhere, it’s on the Belgrave/Lilydale, Frankston and Cranbourne/Pakenham lines – lines which are closer to commuter than metro on their outer stretches. These lines do have a quite a bit of amplification to make it easier – Belgrave/Lilydale has three tracks to Box Hill, Frankston has three tracks to Moorabbin, and Cranbourne/Pakenham has a third track planned to Dandenong (who knows whether that will happen though).
Triplication adds some capacity, and worked ok for the sort of commuter service standard that was envisaged during construction in the 60s, 70s and 80s – but that sort of service standard is poor and ultimately unsuitable for Melbourne today. Most lines need 6-10 trains per hour all day every day. If express services are to be used, they should run at the same fixed pattern, all day every day – giving these lines a two tier service. The focus should be on shorter, more frequent expresses that can be delivered reliably within the parameters of the service standard.
What does this mean in terms of running patterns? For Belgrave/Lilydale, stoppers should run from Box Hill to Flinders St, and expresses stop only Box Hill – Camberwell – Glenferrie – Burnley – Richmond – Loop. For Frankston, stoppers should run from Moorabbin or Cheltenham to Flinders St, and expresses stop only Moorabbin/Cheltenham – Caulfield – South Yarra – Richmond – Loop. For Cranbourne/Pakenham, stoppers should run from Oakleigh to Flinders St, and expresses stop only Caulfield – South Yarra – Richmond – Loop. Additional infrastructure would be required, and ultimately 4 tracks to the intermediate termini is desirable. Here’s what it might look like to commuters:
Hurstbridge and Werribee currently see express running. For more detailed information on my plans for these lines, see here and here. For lines with V/Line trains, there needs to be a concerted effort at segregation, for a more detailed look at what I’d recommend in the western suburbs, have a look at this post.
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