Tuesday, May 27, 2008

Service costs and spreading the peak - 2

As well as fares and frequency, another way to spread the peak is to provide express services during shoulder peak. Generally expresses are even more 'peaky' than train frequency. This is good for inner-suburban passengers (as it gives inner suburban stations a broad peak of frequent services) but less favourable for outer suburban commuters who have increased travel times relative to if they travelled during the height of the peak.

The following times indicate the first and last peak direction express trains passing through Caulfield (or Camberwell). 'Express service' is defined as one not stopping at five or more stations*.

AM Peak

Belgrave/Lilydale: 5:46am - 10:20am
Cranbourne/Pakenham: 6:12am - 8:36am
Frankston: 7:43am - 8:47am

PM Peak

Belgrave/Lilydale: 3:40pm - 7:37pm
Cranbourne/Pakenham: 4:41pm - 6:06pm
Frankston: 5:16pm - 6:21pm

(*) Based on 30/9/07 timetables, which are out of date. Will be updated with new data.

The main limitation of the above spans is that they change according to where you draw the line on the number of stations the expresses miss. For example, there are many trains that express through three stations. This will broaden the span - to most of the day in the extreme case of the Frankston line where it becomes meaningless.

Because it's better to spread the peak and this requires both service and behavioural changes, I opted only to include the faster express trains. This is in line with passenger behaviour - passengers able to will prefer the faster expresses, even if the travel time saving is small. Shoulder travellers on some lines pay a penalty in reduced service frequencies and/or fewer expresses, and tackling this is helping to spread the peak and increase efficiency.

What do the above lists show? The Belgrave/Lilydale lines have wide peak express spans, with express services running well into the shoulders. The Frankston line has very narrow peak express windows (literally 'peak hour'), although it has many lesser expresses outside those times and during the day. Cranbourne/Pakenham has expresses opearating during most peak times. The most conspicuous gaps where there are no or slow expresses are on the Frankston line before 5pm and on both the Cranbourne/Pakenham and Frankston lines from about 8:30am. These early finishes do not encourage 9:30am starting, though if this was encouraged the after 6pm services also need attention.

The narrow express peaks on the Frankston line warrant further attention. Planning for it is complicated by the interplay with the other Caulfield group lines. Service priorities are elsewhere and nowhere is the competition fiercer but on the Caulfield group. The number of Frankston expresses appear to be held back by a need to provide a service to inner suburban stations (Malvern - Hawksburn) that cannot be satisfied by existing Carrum, Mordialloc, Cheltenham, Westall and Oakleigh local trains alone.

Current arrangements have the advantage of relieving the burden on the Cranbourne/Pakenham line (which has heavier patronage but less infrastructure). However Frankston is also a long line with its own distinct needs. These are a wider selection of expresses to serve areas beyond about Moorabbin and more frequent service closer in.

This makes the concept of a two-tiered service based on frequent local and express trains running over a longer span attractive with better use of the existing third track to Moorabbin. However it could also mean that some zone 1 stations (eg Glenhuntly or Carnegie) may lose express trains, and more services would miss the loop, running direct to Flinders Street.

To summarise, spreading the peak by making shoulder peak service more attractive is a viable way to improve capacity and network efficiency. While it can't cope with meeting long-term requirements, it's a worthwhile short and medium term strategy to relieve pressure on the network and has an exceptional return per dollar spent.

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8 Comments:

Blogger Daniel Bowen said...

By my reckoning the last Frankston express goes through Caulfield at 6:21pm, but the point is well made. It appears to be nothing but historical accident that the higher frequencies and expresses last longer on the Ringwood lines than the Caulfield ones.

10:26 pm  
Blogger Peter Parker said...

Daniel, you're right. I've corrected it accordingly.

10:42 pm  
Anonymous wizofaus said...

Not really related, but couldn't find anywhere else to suggest this: has anyone considered trying to set up carpooling services at stations and major bus stops? This would seem to be a logical way to reduce car parking strain, given that a significant number of passengers must be taking quite similar routes to the same point at the same time.

11:39 am  
Anonymous riccardo said...

I would not support park n ride except in a couple of very limited circumstances

-Hallam overpass on the South Gipps Freeway (former General Motors) which has no walkup and no landside development

-East Pakenham overpass on the Princes Freeway (to pick up those who can't be convinced to board at Nar Nar Goon with its poor service) and run the subbies to the end of the wire

11:27 am  
Anonymous riccardo said...

Another place I might consider parknride is next to the Calder Raceway on the new electrified Sunbury service. Might pick up a few from the surrounding area who are not going to be served by a bus.

Sorry Peter, this post has nothing to do with spreading the expresses around. You know my thoughts on this: We need a full time turn-up-and-go timetable, limited expressing on the whole network, mainly comprised of the Vlines carrying suburban passengers on the trunk lines for a premium fare, plus a handful of other express services, run express right up to the suburban boundary full time.

10:05 pm  
Blogger RVB said...

Park and Ride promotes car use no less than building freeways. Carpooling, on the other hand, is an excellent idea - but wouldn't make it one step into Kosky's office before being gunned down by a security bureaucrat.

6:07 pm  
Blogger Peter Parker said...

rvb, I don't share your enthusiasm for car pooling.

While it's faster than the bus it's inflexible (look up the timetable for Route 745D for the nearest bus equivalent!).

What if you have to stay later at work, a home emergency means you have to return early or you're invited out somewhere after work?

You're stuck and lose the impulse mobility that either your own car or good public transport can provide.

Census statistics show 'share car with other person' is the fastest declining travel mode. This shows its appeal is small and efforts to promote it are unlikely to succeed.

7:33 pm  
Blogger Vic Rail (Riccardo) said...

I suspect we might see carpooling have a bit more life kicked into it as a kneejerk reaction to fuel prices.

Most carpooling has always been informal - and between people who know each other well anyway.

Organised schemes are a waste of time for the reasons Peter outlined.

In the US it gets more prominence because of whole districts without any useful PT whatsoever (including 'destination' districts, not just 'origin' districts).

Oddly enough carpoolingh might have worked in the 'good old days' so beloved of Railpage because when people used to work in 'industrial' conditions (with awards, fixed hours, thousands of employees working in similar semi-skilled jobs in factories or the bureaucracies) they would have had more predictable working hours.

10:59 am  

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