Thursday, August 22, 2024

UN 182: An always there network - the two principles public transport needs to work


Always there

If you want people to use public transport in big numbers it needs to be 'always there', 365 days of the year. 

The concept of mass transport operating on fixed routes to fixed timetables was devised by mathematician Blaise Pascal in the mid-1600s.

This was revolutionary; the concept of running a service even if there were no passengers wanting to ride seems counter-intuitive and wasteful. 

However it started the idea of an always there service that people could rely on and even base life decisions, like where to live and work, on. You could call it the 'always there' effect, with no need to book.

An extension of this idea is that service exists over a wide span of hours from early to late, ie not just in and between the peaks. Hence when Melbourne boosted many of its local buses to run 7 days until 9pm in the 2006-2010 period, patronage on these routes increased, including at times when there was already service.

Extend the idea more and you get a frequent service. Which in the best cases mean turn-up-and-go. Public transport then becomes something like water flowing out of a tap, there whenever you want it. Frequent service is true 'on demand', ie on your terms not theirs, provided you're willing to walk a little distance to it. But the trade-off is that by being on fixed corridors you can give it priority over other traffic and build shelters with seats for the short time that you are waiting.  

Over 400 years on and there's people who think they're smarter than Pascal. They back 'demand responsive' service like FlexiRide, which has neither fixed routes nor fixed timetables. Our state government embraced this two or three years back but has since cooled on it as limitations became apparent.

For example it is using GAIC developer funding to replace Tarneit's struggling FlexiRide with more suitable fixed routes. And it hasn't progressed moves to introduce FlexiRide in Greensborough/St Helena, initiated when FlexiRide hype was at its peak. Melton people, who have suffered from their FlexiRide not reliably meeting hourly weekend trains, will be hoping they follow Tarneit soon with more fixed routes. 

So Pascal got the last laugh; compared to fixed route/fixed timetable service, flexible routes are either poorly used or max out to become unreliable if more than a few people want to use it. And the idea of  an 'always there' service remains powerful today. 
 
Network effect

As cities grew it was found that not every destination could be accommodated on a single route. This necessitated transferring for some trips. It was found that further ridership gains were possible by making this easy.

This requires several ingredients: (i) good route geometry to provide adequate speed and coverage and minimise backtracking, (ii) the shortest possible distances between stops of intersecting routes to aid physical transfer, (iii) integrated fares to remove the financial cost of connecting and (iv) either very frequent service or timed connections to minimise waiting times. 


The above rules are not always obeyed by those responsible for building the network. For example  some rebuilt stations (eg Mentone and Edithvale) and so-called accessible tram stops are further from road intersections and buses than those they replaced. And Infrastructure Victoria keeps peddling its modal fare moonshine. A good thing the state government is ignoring them on this.  

Another example of the network effect can be seen in the success (in terms of inducing more driving and dispersed land use that induced it even more) of the US interstate highway system, as explained here. This showed that providing a ubiquitous connected network was more important than trying to assess cost-effectiveness on individual sections or reactively relying on existing demand for future planning. Whether it's public transport or roads, if you make something better more people will use it, with these gains being consolidated as the improvements shape habits and longer-term decisions. 

The benefits of major infrastructure projects are enlarged if other modes are considered. Sydney's new Metro got a lot of limelight this week. However it was accompanied with significant bus network and timetable reform. The aim of this is to reduce network duplication and provide some connectivity improvements to the new Metro stations. Hopefully we get bus reform of a similar scale for Melbourne's Metro Tunnel, with some concepts for Watergardens to Dandenong discussed here

An always there network

Marry these two ideas to get an always there network

Go to Doonside in Sydney's outer west and check its train timetables. You will see a 7 day service about every 15 minutes even at 5am Sunday or midnight any night. Ditto for most other stations in Sydney. That's what an 'always there' network looks like. It's legible and easy to communicate. And it helps explain why Sydney's train patronage is much higher than Melbourne's despite having fewer stations. Sydney's Metro has lifted the bar even further with 5 to 10 minute frequencies common. 



You can't use Sydney's density or traffic to explain all this away either. Other city comparisons demonstrate the centrality of the 'always there' network, even if other factors are unfavourable. Brisbane versus Perth is the most notable Australian example. Despite having half the lines, half the stations and a lower population, Perth's rail system outperforms Brisbane's on patronage due to operating its trains every 15 minutes  all week versus 30 minutes for Brisbane. Unless it's after mid-evening there'll always be a train soon in Perth. And the planning of its bus routes, with them feeding rather than paralleling trains gives Perth a network effect that Brisbane lacks. 

Even when it decides to substantially increase metro rail services (rare events insufficient to arrest declining per capita service), Melbourne has taken a different tack to Sydney. Instead of going for the 'always there' approach it only boosted services during times that it thought would be busiest, typically midday and not early morning or evenings. 

This habit goes back years. An example was the 11am - 7pm increase in Sunday train and tram frequencies while Jeff Kennett was premier in 1999. 2012 saw a further big increase to every 10 minutes on weekends for Ringwood, Dandenong and Frankston (under another Coalition government). However the busier lines of Ringwood remained with 30 minute gaps weekend evenings and Sunday mornings, with the quieter but marginal seated Frankston line getting a modest upgrade to every 20 minutes at all times but early Sunday morning in 2021 (under Labor).

What this means that even on our busiest line (Dandenong) you get frequent service between about 11am and 7pm. But outside this service falls sharply to every 30 minutes on weekends, especially after 7pm and Sunday mornings. 


The sharp fall-off means that if you are making a return trip of more than a few hours there is a high chance that you'll get a frequent 10 minute service in one direction but face 30 minute gaps in the other.  This is very different to a flat Sydney-style timetable with 10-15 minute intervals early to late. Hopefully the Metro Tunnel fixes this for Dandenong - Watergardens but there is not yet word on whether other lines will get relief from their 20, 30 and 40 minute gaps at key times people travel.  

Service designs with inconsistent frequencies or sharp fall-offs also hurt messaging. Overall a consistent 7 day 15 minute frequency, like at most Sydney stations, is more sellable than what's found at Dandenong, which could be every 10, 20 or 30 minutes. It also makes early start/late finish trips much more attractive, with weekend V/Line tourism to the regions and airport trips the key beneficiaries. 

Sydney's approach of a frequent service until after midnight is obviously the gold standard. But smaller cities, such as Perth and Auckland, have a pattern of 15 minute daytime Monday to Sunday frequency on their key routes, aiding legibility. Melbourne doesn't have this consistency, with early weekend evenings and Sunday mornings being a particular unresolved issue over many decades. 

Conclusion

Public transport is not just about building infrastructure, as prominent as this is at the moment.  

Design and operation of the network is equally vital. 

This should be informed by the concept of an 'always there network' as outlined above. 

This would make public transport services useful in many more peoples' lives, and maximise the benefits of the infrastructure we build. 

See other Useful Network items here

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