Investment, risk and success: making interchanges work

Though they sound like something from a business seminar, today I will demonstrate that these finance-like concepts are key to effective passenger interchange.

To transfer from a train to a bus requires investment in both time and physical effort. Ideally this effort is small, as with efficient interchanges and able-bodied passengers. But in others passengers may need to climb stairs, negotiate busy roads and walk several hundred metres. Especially in poor weather or with older passengers the 'investment' and energy is significant. And passengers do make calculated decisions based on these hard-headed criteria.

Still on the business theme, there's risk and success. Risk is the chance of the attempted transfer not working. If the passenger perseveres, the main consequence is a long wait (if a bus has just been missed). If they abandon the transfer, the passenger might retrace their steps, walk home or call a taxi. In both cases they are unlikely to risk the transfer again, assuming they have alternative transport. Success, in contrast, generates repeat patronage the next time that trip is needed.

Successful interchanges require the following:

1. Low investment/low commitment. It should not require much effort to make the transfer. Should it not work out, little time will have been wasted, and other routes or alternative transport can be used to complete the journey with minimum delay.

2. Low risk/high success. Information increases certainty and certainty lowers risk. If the bus is not due for a while, passengers must know about it as soon as they alight the train (eg from bus timetables at station exits), and not until after they've trekked to the bus stop on the other side of a major intersection. The waits themselves can be minimised by co-ordinated bus scheduling. Variability in access time and the chance of missing buses can be reduced with direct walkways, underpasses and crossings. Good wayfinding signage improves navigability and passenger errors. All these lower risk and increase the chance of success.

To summarise, low investment, low risk and a high chance of success is what makes a winning business proposal. Successful transport interchanges are no different.

A successful interchange

The diagram below shows a small but successful transport interchange. The three elements that make it so include information, access and service co-ordination.

Some of the new bus/rail interchanges on the Perth suburban rail system can claim to score highly, since passengers can scarcely alight from a train without bumping into a bus timetable. Werribee in Melbourne is one of our better examples, with good access and service co-ordination, but some limitations with information.

An unsuccessful interchange

Below illustrates a poor interchange. Passengers alighting from the train have no idea of bus times. Station exit locations maximise walking distance. The road might be difficult to cross as no provision has been made for pedestrians. There is a high chance the bus will have left before passengers will have been able to reach it, but long waits are equally likely due to poor service co-ordination.

Epping Station* is one of our better examples of a poor interchange, with its main redeeming feature the co-ordinated TrainLink bus.

(*) Though monies have recently been budgeted for this interchange to be upgraded.

Crowds, delays and late-running - Part 2

It's only slightly harder to find a parking spot in a car park that's 91% full than one that's 90% full. It might take 33 seconds instead of 30 seconds, for example. However it's twice as hard to find a spot where it's 99% full instead of 98% full. Finding one would take twice as long on average. And when it gets really full, from 99 to 99.9%, you'd expect parking would take 10 times longer, since there's only 1/10 the number of free spaces.

This is the rule that even a tiny increase in usage of a system nearing capacity causes service faults (or more accurately, their impact) to rise exponentially.

In Melbourne we are currently experiencing the same on our peak-hour trains. Operators struggle to meet performance targets and rising patronage is cited as the key reason why. Today's stats compare to five years ago, where the likelihood of your train being late or cancelled was 50 to 70% less, but patronage was also lower, and if your train was cancelled you were more likely to be able to board the next one.

Studying lateness and cancellation figures is useful but don't always tell the full story, especially as seen by the passenger. In some cases a cancelled train may be effectively replaced by the previous running late, and the overall impact might be negligible. But in others, even a 2 minute delay could cause buses or other trains to be missed, resulting in 15 - 60 minute delays. Similarly the cancellation of a busy service might lengthen waits as passengers are unable to board the next three or four crush-loaded trains.

For simplicity, let's assume that trains can carry 1000 people crush-loaded. An on-time morning peak train approaching Station A already has 800 on board. As 80 people board at this station, all can board.

The same is also true for the next station (Station B). By the one after that the train will be full, but assuming some alight (eg a nearby school is a popular destination) then Station C's 80 people should also just be able to fit on.

The situation changes if the train departs late.

For a start there will be more on the platform at previous stations, as some intending to catch the following train will have started walking on. The total number of people walking through the validators at all stations before Station A could be 50 persons per minute (but may be more).

If all these people board, and the train departs the terminus 3 minutes late, then that's at least 150 extra people on board by Station A. With 950 people already, and at least 80 wishing to board, then at least 30 will be left behind. With the crush load train presenting at Stations B and C, most of their passengers will be unable to board.

Why did I say 'at least'? The graphs in Part 1 show that as a train approaches capacity, boarding time rises exponentially. So the train will likely be 5 or more minutes late at Station A, and even later down the line. And in that time more people (say 5 or 10 more per minute on average) will have passed through the validators at Stations A, B and C, all expecting to catch the train. So the train could well be full even before it reaches Station A.

Hence we have three station platforms of passengers, increasing every minute, unable to board the train. The next train, assuming it left on time might be emptier than usual on leaving the terminus, as some of its passengers will have boarded the previous late-runner. And for a while it might even be only a couple of minutes behind that train, its progress retarded by the slower-loading train in front. However as it travels more of its passengers will be comprised of those left behind than the increasingly delayed earlier train, and early arrivals for the train after that. So the second train that started on time could end up also being late and crowded.

On the busier lines in Melbourne, this and the following several trains will also be leaving passengers behind. And at the more inner stations (especially those served by one line only and bypassed by expresses) passengers may need to wait for several trains to pass before being able to board. This causes the actual delay experienced to be higher than what might be apparent from train running data alone (as some trains were unboardable).

To summarise, a line with frequent trains that are not crush-loaded (eg Belgrave/Lilydale) will outperform ones that are (Pakenham/Cranbourne and Sydenham lines) in reliability. Belgrave/Lilydale are nearer the 90% carpark full level, while the others are like 99%. And it's much easier to find 100 passener places in a hurry to clear a platform on the former than the latter.

Crowding, delays and late-running - Part 1

A points failure, lightning strike or level crossing accident delays thousands of passengers on a busy line. Some get frustrated and blame the train operator. Others take refuge in a good book. But for me such incidents are beneficial in that they force me to think about them and their management. I confess that blog postings here would be fewer if I lived on a shorter, quieter and less delayed line!

The following graphs illustrate some links between passenger loading, delays and their propagation (click for a larger image).

Low-tech passenger information

Passengers would need to be blind or stupid not to notice this:

One way to advise of cancelled trains:

Simple? Yes. But blackboards do the job, cost almost nothing and reflect well on the station staff involved. They are labour-intensive, especially if they need to be changed and/or are on platforms away from the main building. It is at large stations and nearby bus stops that electronic displays come into their own, at the cost of flexibility and (possibly) loss of local control.

Why fast interchange matters

a response to a Railpage discussion about Box Hill and the importance of minimising bus-train interchange time

There's worse interchanges than Box Hill, but best practice is that train to bus interchange should be maybe 30 - 60 seconds via just one ramp, steps or escalators (eg Werribee, Boronia or newer Perth suburban stations).

And it should not be possible to exit any suburban railway station without almost bumping into a bus timetable or information - something that is denied to Box Hill passengers.

Every minute longer in bus-train access times lengthens bus standing times by 2 minutes, assuming a co-ordinated pulse timetable system. This reduces the capacity of bus interchange and is poor efficiency. Where stations are midway along a bus route (and not at the end like Box Hill) long bus dwell times can also increase journey time for through passengers.

Two 'perfect connection' examples, both assuming a 4 minute buffer to allow for late trains/buses.

* 1 minute station - bus access time (ie good design)

Bus arrives: 9:55am
Access time: 1 min
Wait time: 4 min
Train Arrives/Departs 10:00am
Access time: 1 min
Wait time: 4 min
Bus departs 10:05am

(min bus dwell time 10 min)

* 3 minute station - bus access time (ie poor design)

Bus arrives: 9:53am
Access time: 3 min
Wait time: 4 min
Train Arrives/Departs 10:00am
Access time: 3 min
Wait time: 4 min
Bus departs 10:07am

(min bus dwell time 14 min)

The general concept is better explained in the diagram below:

Time is money. Multiply that extra 4 minutes by the number of bus movements per day, and then per year. It's big bikkies! Or try to economise by skimping on connections, but since that may add 30 minutes to passenger travel times it's a false economy as they'll drive instead.

In short, each second counts, and no effort should be spared in improving interchange, whether the delays be caused by poor initial design (Box Hill), a botched redevelopment (Melbourne Central) or placing car ahead of pedestrian access (most places - Caulfield example below).

Service standards for buses

When people front up to a bus stop, they don't know what to expect.

For a start (unlike a tram stop or railway station) it might not have a timetable.

But assuming it does, the timetable can show a big variations in services. For instance, it may run frequently on weekdays but not at all on Sundays. Some services operate weeknights but not on Sundays, while other go Sundays but not weeknights. Regular routes may provide a superior service to SmartBuses on some days but not others. Public holidays and reduced December/January timetables are other causes of confusion as there are no network-wide standards.

Since the service levels of some bus routes can be low, it is easy to tar all with the same poor brush. And this is understandable given that even a single route can be simultaneously good or poor depending on the day of the week and time of the year.

The SmartBus program provides a premium and visible level of service on five routes. Currently they are all in Melbourne's east but eventually they will extend around the northern and western suburbs via proposed orbital routes. Except possibly for peak times, SmartBus provides a consistent level of service on weekdays. However weekends and evening SmartBus services still have a way to go, with some regular non-SmartBus routes offering superior service.

At the local level there are the minimum standards improvements which will give local routes at least a basic hourly service until 9pm and standard public holiday service arrangements. Over 200 of Melbourne's 300 bus routes are to be upgraded, and we are currently just under half way through.

When minimum standard upgrades are finished, it will be possible to talk about a minimum service standard of a bus at least every hour until 9pm. And given the 90%/400 metre rule, we could add it would be within a 5 minute walk of most homes as well.

Left out of this is a big body of busyish routes that are neither SmartBuses nor quiet local routes. They may serve shopping centres, universities or a major corridor. They may be highly patronised routes, such as the 200-series out to Sunshine or 250/251 to Northland/Latrobe University. Or they might be the only direct link for some suburbs missed by trains or trams (eg various City-Doncaster routes). Many of these already operate to quite high service standards, and even, as noted before, run more frequently and later than SmartBuses.

It is these intermediate/'nonSmart' routes that are currently getting a bad deal. They don't get the promotion or infrastructure of SmartBus services. Neither have they had the public holiday standardisation of local routes. Where these services comprise two or three similar routes, timetables may not always be in composite form, so Joe Public can't readily see the higher service level offered. Unlike SmartBuses or local routes they don't have documented service standards. To the passenger it's just another route number, and study of a timetable is needed before knowing whether the route is hourly until 7pm or every 20 minutes until midnight. These good but 'non-smart' routes will never reach their potential until this is addressed and their superior service is highlighted.

The solution to all this is contained in a media release quoting Bob Cameron, the Member for Bendigo West, when announcing upgraded local bus services in Bendigo.

The salient sentence is this:

"There will be services at least every 30 minutes on prime routes and every hour on secondary routes,” Mr Cameron said.

Since the hourly 9pm 'minimum standards' are just that - minimums - we can label all those routes that conform as 'secondary', just as Mr Cameron did for Bendigo's quieter routes.

SmartBuses are usually better than that, so it's logical that they are 'primary'. Ditto for the 'nonSmart' routes if their service level is high enough. Document these primary standards, make some minor improvements to ensure adherence and standardise public holiday arrangements and we've effectively doubled the SmartBus network for very little cost. After all, who really cares if a bus is 'smart' or otherwise if it's like Route 220 and runs every 15 minutes until after 11pm?

The few routes that conform to neither primary or secondary status (perhaps because they are peak-hour only or serve semi-rural areas), can be labelled 'tertiary'.

Once we have a proper primary/secondary/tertiary standard, it can be explained easily to passengers; just as the MP did in his one-liner. We can say things like: Primary routes have a bus at least every 15 minutes during the day and every 30 minutes until midnight and secondary routes are at least hourly until 9pm. This exercise now is impossible since current timetables have dozens of variations and requires hundreds of words to explain.

Primary service can be promoted at stops, in timetables and on websites similar to what Adelaide does with its 'Go Zones'. Local public transport maps at all railway stations and bus interchanges would show the primary routes as thicker lines. The remaining secondary and tertiary routes would be thinner lines.

By differentiating primary and secondary routes, and heavily promoting the former, we've created a quite different, more versatile and more usable bus network. And this should translate into higher bus patronage overall, with the potential of upgrading popular secondary routes to primary status.

And we've met the challenge set at the beginning, which was to ensure that passengers know what service to expect, just as they do now with trains and trams.

Using a Metcard ticket vending machine

A short video explaining how to use the Metcard ticket vending machines found at Melbourne railway stations. Versions of the smaller coin-only machine pictured are also used on trams.

Metcard machines will be with us until Myki smartcards start in about two years.

Professional versus political in service planning

The interplay between professional opinion and politics and the resultant services we get is always worth watching. The priorities that prevail are particularly noticeable during times of significant growth, such as we're currently seeing with Melbourne's bus network.

I count the operators, industry associations, private consultants, transport academics and (marginally on this topic) Metlink as the 'professionals' who pride themselves on their expertise. The 'politicians' comprise community groups, local governments, MPs, ministerial staff and the Minister herself who are 'generalists' but know what they want from a transport system. In the middle of this interplay is the Department of Infrastructure which has professional and political elements and must reconcile both.

Objectives naturally differ between the two main groups, which is why their priorities will vary. Despite what one group may say, both are necessary. Decisions and funding come from the politicial while expertise comes from the professional. Professionals need to humour the political process and the occasional publicity tricks, while politicans must acknowledge that networks aimed to please everyone end up pleasing no one.

Professionals

A bus network designed by professionals to maximise patronage would probably comprise frequent buses running along a grid of main roads with bus priority. Not only would it have the highest patronage, but such a network would also have the highest farebox recovery ratio, the highest boardings per kilometre, the highest average bus loading and the lowest greenhouse emissions per passenger.

This means a more legible network with fewer but more frequent and longer running routes. Poorly used routes might be withdrawn if it can be demonstrated that higher patronage is possible by improving services elsewhere. Hence passengers may need to walk further to their nearest bus stop. Key performance measures would include direct routes, wide service hours and high frequencies.

Politicans

The 'politicians' network emphasises route coverage - even to areas that could never sustain a well-used bus service. This produces impressive network maps, but generally low service levels. Network legibility suffers as routes are split and occasional deviations are introduced in response to lobbying from constituency groups. Politicans' preference of coverage over frequency is not recent; recall the railway 'Octopus Acts' of the 1880s which proposed miles of unviable rail lines and others that only saw weekly trains.

In its defence, the politicians' network gives priority to social need over maximising patronage, efficiency or environment. And of the socially needy, the organised might receive preference over the casual passenger by scoring a deviation that lengthens the latter's trip.

A high route coverage standard is generally provided, but at the expense of other important patronage attractors such as directness, operating span and frequency. This has meant that the politician's network mainly provides a social service for people without cars and has a low potential to grow patronage or further environmental goals. An example politicians performance measure might be something like '90% of the population is within 400 metres of a service', with little concern over whether the service is every ten minutes or twice a day.

What is our current network like?

The existing local bus network is more like the politician's network than the professionals network. In some ways this is understandable given that perhaps 80% of bus operating costs come from the taxpayer (not the farebox) and thus must pass through political hands. The routes that approximate nearest the professional's network (ie direct and frequent) are the SmartBus routes and some inner-suburban routes that have retained tram-like service levels.

Recent and proposed changes

Elements of both the political and the professional can be seen in recent and proposed changes.

Case study: Gowanbrae and Route 490

A recent triumph of the political (and hence, in a way, democracy) is the proposed Route 490 to Gowanbrae. This is an enclave isolated by freeways, railway and a river. It has no shops, services or public transport. Its roads are too narrow for standard buses and there is only one way into the suburb, making an efficient service to the nearest railway station impossible to provide.

No sane urban planner would have recommended Gowanbrae be developed in its current inaccessible form. And this error having been made, no efficiency-minded transport professional would recommend a bus since other areas have greater merit. Transport-wise Gowanbrae is a basketcase, and perhaps the only efficient public transport project possible would be a high quality cycleway to Glenroy Station!

Socially there is a case to provide transport to an area currently distant from it. And politically, active residents and council have lobbied for years. Their patience was rewarded; last week the Minister for Transport announced that Gowanbrae would soon get a bus service. Everyone was happy and no one has yet been impolite enough to mutter phrases like 'opportunity cost'.

SmartBuses

SmartBuses are at the other end of the spectrum. Direct, fast (if provided with priority), frequent and (ideally) connected with trains, they make the public transport network far more versatile and not just a feeder for CBD workers. As existing SmartBuses have shown, this is exactly what is needed to boost patronage. Hence all in the 'professional' camp support SmartBuses, even if some have reservations about orbital routes.

Local routes

Local routes are somewhere in between. The main changes to them at the moment are the 'minimum standards' upgrades. These will upgrade most local routes to at least an hourly service until 9pm seven days a week. This compares to the 7pm finish/6 day running that was normal until 2006.

Is this mainly 'political' or 'professional'? My answer is a bit of both.

There is no doubt that minimum standards were needed. No professional or politican who supported improved buses could oppose them. So I call that a consensus. Even though the light evening patronage on some might make the professionals wince and prefer a more intensive service on the popular routes.

However the order in which services were upgraded cannot be the making of a transport planning professional. As an example the lightly used Route 701 was one of the first to benefit. On the other hand popular nework-strategic routes like 665 and 737 had to wait until 2007 or 2008. Though this doesn't matter much anymore (since many important routes have now been upgraded) the order that it was done does give some insight to the process; criteria other than network utility or patronage potential must have been key.

Bus reviews and current service planning

With a few exceptions, the minimum standards program represents an upgrade to existing routes. The bus review process reaches further, promising revised local networks.

The interplay between professionals, politicans and the public has been fascinating during the reviews currently underway. The results of these are yet to be seen, though much of what is said (and public sentiment) has favoured the 'professional' aims of directness, operating hours and frequency over the political. However the politcal has not been completely absent, since there have been calls from groups or councils for deviations, extensions or improved coverage, especially in newer areas.

Current service planning appears to be driven by the following standards:

* 90% of the metropolitan population within 400 metres of transport (high target)
* Most routes running until 9pm, 7 days a week (moderate target)
* A 'safety net' 60 minute service frequency for local services (low target)

Both political and professional influences are apparent. If there is a skew it it towards the political, as seen by the high coverage target. The main effect of such a high target is that with a given level of resourcing it is harder to make more local routes run every 15 or 20 minutes instead of 40 or 60 minutes.

A slacker coverage target eg '80% within 800 metres' combined with a tougher hours/frequency target eg 'at least every 15 min day/30 minutes night' is likely to be favoured by professionals and deliver better patronage outcomes. However this will leave large areas (not just Gowanbrae) without service, so these need some modification since the political calculus is adverse (removing service from 100 people is 'courageous' even if 1000 people benfit from an improved service nearby).

Thus we might end up with a compromise approach where we have a breakdown of (say) 40% primary routes (every 15 min to better than minimum hours), 40% secondary routes (every 30 min to minimum hours) and tertiary routes (say every 60 min). This mix would greatly lift the status of the sub-smartbus but direct local routes and provide a far better network than SmartBus + trains alone. If the bus reviews can result in the implementation of that sort of service, then it should be possile to reasonably satisfy both professional and political tendencies.