Monday, March 28, 2011

A look at Metro's May 2011 timetables

The fomerly arcane world of train timetabling has assumed greater profile in the last few years. Decades-old operating patterns, often a legacy of years of negative or slow passenger growth, have been challenged as patronage rebounded and reached record highs. The timetable has become key to how more passengers can be reliably carried on existing infrastructure. And, unlike the 2004 – 2008 period, where patronage growth outstripped service provision, the delivery of new trains is allowing significant weekday service growth for the first time in years.

The construction of rail infrastructure lagged roads in the early 2000s. Rail's pace picked up in the late 2000s, with even larger projects, such as the Regional Rail Link and Melbourne Metro, featuring in government transport plans. Though critical to how this infrastructure would be used and integration between modes, timetables and service planning had a much lower profile. The main exceptions were both outside metropolitan rail; the Regional Fast Rail service improvements and various bus service upgrades.

The highest-profile championing of the importance of timetables and service levels has come not from government, the Department of Transport nor any of its transport plans, but from Metro’s Andrew Lezala, who advocates a ten minute base train frequency and fewer stopping patterns. Higher frequency improves connectivity with other modes and encourages a spontaneous metro-style ‘turn up and go’ method of travel. Fewer stopping patterns increase legibility and reduce the complexity of trip planning; if a desired pattern runs every ten minutes instead of every thirty there’s no gain from trying other ways to get there. Also demand isn’t artificially peaked by a few infrequent super-express services, making loading more consistent and easier to manage.

It is towards this style of network that May’s timetables should be judged. In many respects it's an interim work. Weekday times only are changed, though some lines gain 6-car trains on weekends.

Some loose ends are tidied and Lezala's 'ten minute network' has spread to two lines, creating a cross-city group between Newport and Frankston. There is also a major boost to weeknight service on four lines, with their evening frequency aligning with trams but disaligning with SmartBus and trains on other lines.

In other areas new loose ends are created. Services from May are less legible, less clockface and less metronomic than our current timetable on a couple of lines. In some cases this may be a trade-off against a higher good on a nearby busier line. Or it may represent a partial implementation of a future bolder service concept.

Metro's Destination Better website explains and reveals the new timetables. It might be worth referring to these while you read the summary and commentary on the changes below.

(tables below derived from Metro material and examination of timtables - notes in blue represent service increases)

Northern group

The northern group, and especially the lines through Newport, have had the most radical change. The process of seperating Altona and Werribee trains has continued, with the former being swapped with Williamstowns to operate as a shuttle during the off-peak.

Williamstown trains now pair with Werribee trains to form an even ten minute service between Newport, Southern Cross Station and Flinders Street. These then continue to Frankston, creating a new 'cross-city' group that avoids the City Loop. Hence it will now be possible to board at Caulfield or South Yarra and have direct trains to Footscray and Newport every ten minutes without negotiating the intricacies of the Loop.

The most controversial aspect of the new timetable will be in the west.

Werribee's off-peak timetable will drop from 6 trains per hour (not evenly spaced) to 3 trains per hour (evenly spaced). This represents a frequency cut. Although it can also be said that the current timetable's higher frequency was largely wasted because the intervals between trains are uneven, there are no major mid-line trip generators to generate off-peak shopper patronage, and the alternating stopping patterns offered poor legibility and varying travel times.

As a trade-off however Werribee does receive significant peak and evening service increases. Express trains will increase from approximately every 20 minutes to every 10-12 minutes. And evening headways will shorten from 30 to 20 minutes until approximately 10pm.

Some controversy is likely to come from residents of Altona, and, to a lesser extent, Williamstown. Their even and metronomic 20 minute peak service frequency will be downgraded to the forgettable 22 minutes; stated to be the cost of delivering the boosted service to the busier Werribee, Hoppers Crossing and Laverton stations. On the bright side, Altonians should be able to get a seat on the trains that do run as they will start at Laverton and not be full of passengers from Werribee and Hoppers Crossing.

Off-peak travel from Altona to beyond Laverton and Newport will require a change of trains as the Altona service will be a shuttle between Newport and Laverton (swapped with Williamstown). In addition a trip to a loop station will require a further change at either Southern Cross or North Melbourne as off-peak trains will run direct. In the evenings Altona trains will continue to run from the city, and like other lines through Newport will have their frequency increased to 20 minutely until about 10pm.

Clifton Hill group

no change

Caulfield group

Most of the Caulfield group has its biggest changes during the afternoon peak period and evening.

Frankston's off-peak trains currently alternate between the City Loop and Flinders Street. The result is that the even 10 minute service until the city fringe is diluted by the variations in the city. The May timetable through-routes all off-peak trains to Werribee or Williamstown via Flinders Street, Southern Cross, North Melbourne, Footscray and Newport. This improves consistency and provides a new cross-city corridor with services every ten minutes. Something to watch is timekeeping; the Frankston line is Melbourne's least reliable and passengers in the west will be hoping that through-linking will not delay their services.

For many years the Burnley group has had a much wider peak service window than the Caulfield group, and particuarly the Frankston line. This blog had a comparison showing that while peak express services on the Burnley group ran for over three hours, peak hour according to Frankston line timetables was just that (5 to 6pm). The May timetable dramatically changes that - it has Frankston peak expresses running between 4 and 7pm, at approximately 20 minute intervals. This makes fuller use of the third track to Moorabbin, which before recent peak service improvements was poorly utilised.

The Cranbourne and Pakenham lines also receive timetable changes. Like Frankston the pm peak is extended. Also notable is the upgrade from a 30 to a 20 minute evening service frequency on both lines. This follows a previous upgrade that saw services beyond Dandenong improve from 60 to 30 minutes. A quirk is that weeknight trains will now run twice as frequently as weekend daytime trains.

Sandringham, which was the first, and for many years the only, line on the network to have 20 minute evening frequencies also gains from the May timetable. Here there's an increased peak frequency and a couple of early morning trains starting from Middle Brighton. Early evening service frequencies will also increase from 20 to 15 minutes.

Burnley group

This group, historically Melbourne's busiest and best serviced, will also have substantial timetable changes.

Most interesting is the post morning peak period. While its am expresses have always continued after those on the other lines have ceased, this new timetable extends them until noon. Belgrave and Lilydale off-peak trains will remain at 30 minute frequencies but will run express to the city. Trains from Blackburn will provide a 15 minute service to the quieter stations. This arrangement, to run until approximately noon, is unusual since it provides substantial express running outside peak periods and could be a test of a possible future expanded two-tier service.

Both Belgrave and Lilydale are long lines - not dissimilar to Frankston. However their approach to service planning in this timetable is very different. Whereas Frankston has a turn-up-and-go ten minute stopping all stations service, Belgrave and Lilydale will offer a timetable-critical 30 minute service with significant express running. In addition the non-major stations from Ringwood in will remain with a 15 minute service.

Hence these lines will offer an interesting contrast of high frequency/stop all stations versus low frequency/express running in outer suburbs (my personal prejudice favours the former because of the improvements to end-to-end travel speeds possible with better bus connections that higher train frequency facilitates).

Peak services on the Burnley group will also be shaken up. Alamein and Blackburn trains will run via the City Loop (instead of direct to Flinders St) in the morning. The latter provides consistency with the after-morning peak Blackburns. Glen Waverley am peaks will be removed from the loop, with transfer at Richmond suggested. However, as tends to be the pattern for other lines converted to more direct running, their passengers have been rewarded with some frequency increases.

Conclusion

The new timetable will increase the number of services on three of the (current) four railway groups. More passengers are likely to gain than lose. The most memorable innovations introduced are likely to be the cross-city through-routing, the expansion of the ten minute network and the boost to early evening services (which partially restores some of the 1978 service cuts, made when patronage was half today's and still falling).

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Friday, March 11, 2011

More Aural timetables: analysing individual route connections

It's been a busy week in Melbourne transport; trains off the rails at sidings, disruptions due to power glitches, new fares and major events in the city this weekend. Nevertheless I'm still doing the timetable beat thing, and here's the latest.

Earlier experiments emphasised headway harmonised networks. If the network was frequency harmonised it would produced a nice rhythm, repeating in as little time as possible. An unharmonised network would sound more random, with no dominant rhythm, or a longer rhythm with the same connections only repeating every couple of hours.

Harmonised headways is a necessary but not sufficient condition for good connectivity. A bus matching a 20 minute rail service isn't good if it departs as the train is pulling in.

What is really important is the waiting periods between when the train arrives and the bus departs. Too short and it means a missed connection, especially if the train is running late. Too long and the bus is no faster than walking.

This part quietens down the pulse (but it's still there if you listen hard) and emphasises the waiting periods. It does this by applying a tone for the duration of the wait (again 60 min = 1 second, 6 min = 0.1 second).

Because the human hear is more sensitive to pitch than duration, I also used different pitches. I went for three pitches only (low, middle and shrill) to aid recognition. A low pitch is a long wait (>15 min), a medium pitch a medium wait (5-15 min) and a shrill pitch is a short wait (<5 min) which also risks being a missed connection if the train is late. I'd have liked to differentiate between a near-ideal 6 min connection from a longish 14 min connection, but that would have meant another tone which slows recognition. So I stuck with three. Music afficiondos will hear that I've used notes - something I intend to keep doing with future aural timetables.

At the end I've got a comparison between the harmonisation possible between 20 min/38 min frequencies and 20 min/40 min frequencies. The tonal difference is quite stark. Even though it's a slighly lesser frequency, a well-timed 40 min service can provide predictable connectivity is scheduled carefully, whereas a 38 min service has a plethora of good, bad and just missed connections, happening at seemingly random intervals.

There haven't been many comments on this, so whether you think aural timetable have potential or are just a useless curiousity, they'd all be welcome here.

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Wednesday, March 09, 2011

Aural Timetables: checking the network's pulse

The previous post introduced the concept of converting timetable data into sound. The technique was suggested as a means of gauging co-ordination between intersecting routes.

Now I've got some real times. I try to apply this stethoscope-like tool to check the pulse of connectivity at selected suburban railway stations in Melbourne.

Hear the difference between unharmonised and harmonised service frequencies at these interchange points. The tunefulness of the latter demonstrates that not only does good service planning produce good connectivity, but also good sounds as well!

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