Is commuting killing us?

Assembly kit for Manhattan street grid

Long commutes cause obesity, neck pain, loneliness, divorce, stress, and insomnia. Your commute is in fact killing you, according to this story published in Slate last week. And it’s bad for others too – in his Melbourne address last month, Robert Putnam argued that a ten minute increase in commute time reduces social capital by 10%. Richard Florida says it’s time to put commuting right beside smoking and obesity on the list of priorities for improving the health and well-being of Americans.

I’m always bemused by these sorts of claims. Apart from the fact that the majority of commutes are relatively short, they neglect the salient fact that people spend time commuting because it’s worth it – that’s how they earn their living. And in general, the further they go, the better the job and/or the better the house. Commuting is a bit like having children – it costs a squillion, but for most people it’s worth it!

The reality is that most people prefer to commute some distance. This study of US commuters by Redmond and Mokhtarian found that 42% of their sample are happy with their current commute i.e. their actual travel time and their ‘ideal’ commute time coincide. People seem to like some space between work and home. They found that 7% actually say their commute isn’t long enough!

Nevertheless, the study also found that just over half feel their commute time is too long compared to their ‘ideal’ commute time. That finding, however, doesn’t really say much. The trouble is people don’t make unconstrained judgements like this in real life. If asked, rational people will of course say they would like less of the boring things in life and more of the interesting and exciting things. If they’re not forced explicitly to consider the cost, people will naturally acquiesce when they’re posed questions of this sort. It’s a difficult concept to measure, so a much better guide to commuting time preferences is what people actually choose to do in the face of real-world constraints.

It turns out workers don’t tend to spend inordinate amounts of time commuting. This analysis of US Census data shows that 45% of one-way commutes in US metropolitan areas take less than 20 minutes and only 8% take more than 60 minutes. This US survey found that 81% of commuters spend less than half an hour getting to work. In Melbourne, more than half of all trips to work (54%) take less than 30 minutes. Only 12% of commutes take longer than an hour and only 3% more than 90 minutes.

Having said that, whether or not an hour a day spent commuting to and from work is ‘inordinate’, depends on what it yields. The question can’t be addressed sensibly without considering the benefits as well as the costs. We spend time on a host of activities like sleeping, cooking and taking the kids to sport because we feel they are necessary to derive the associated benefits. Likewise, commuting provides something that’s extremely valuable – income. That’s a basic, a necessity. But work also provides a host of associated benefits like status and social interaction. The bottom line is we commute because it’s worth it – we’ll minimise commute time subject to other constraints but we don’t expect it to cost nothing. Read the rest of this entry »


– Do governments spend too much on roads?

Total passenger travel by mode in Australia (billion passenger kilometres) Souce: BITRE

The Australian Conservation Foundation (ACF) got a lot of press recently with its claim that “governments across Australia are spending at least four times more on building roads and bridges than on public transport infrastructure“.

The claim is in a new ACF report, Australia’s public transport: investment for a clean transport future, which argues for a rebalancing of the transport capital works budget, recommending that “two thirds should be spent on public and active transport measures and one third should be spent on roads”.

I agree with the ACF that more needs to be spent on public transport, but I don’t think the “roads vs public transport“ logic does justice to the complexity of the situation. There are a number of reasons why more public funds are spent constructing roads than rails.

One is that people drive much more than they use public transport. According to the Bureau of Infrastructure, Transport and Regional Economics (BITRE), Australians travel almost eight times as many kilometres by car as they do by bus and rail-based public transport. The money is going where the demand is. If you accept the ACF’s numbers, public transport is actually getting a disproportionate share of public construction expenditure. Roads are needed even if travel is confined to foot and horse-drawn vehicles. The Hoddle grid in Melbourne and the avenues and streets of Manhattan were designed before cars were invented – land has limited value if it can’t be accessed.

Construction expenditure doesn’t in any event tell the whole story. Most funding for public transport comes via operating subsidies. Although getting comparable numbers is hard, Sydney University transport academic, Professor John Stanley, estimates that in states like NSW and Victoria, total public funding for public transport and roads is probably pretty nearly equal. In his 2008 report, Public transport’s role in reducing greenhouse gas emissions, Victoria’s Commissioner for Sustainability noted a significant shift in funding priority from roads to public transport at the State level.

Another reason roads are important is for the distribution of freight within the metropolitan area. According to BITRE, the number of tonne kilometres of urban freight transported by road within Australia’s eight capital cities in 2007/08 was more than five times higher than it was in 1971-72. There is simply no practical alternative to road for tasks like restocking those hundreds of supermarkets that supply suburban households with food and household goods.

But most importantly, roads are also extremely important for public transport. For example, in Melbourne, the Doncaster Area Rapid Transit (DART) system, the Airport-CBD Skybus service, and the city’s three new orbital Smartbus transit services, all use buses. Because they use the existing road network, these systems do not require significant new land acquisition and construction. Some trunk lines might in time justify conversion to light rail services as patronage increases, but they too can use existing roads rather than require a dedicated right of way.  Read the rest of this entry »


Is transit patronage really growing this fast?

'The Beauty of Maps' - BBC TV series

I’ve noted before that public transport patronage in Australian cities is increasing, but I didn’t realise just how dramatically it has escalated in Melbourne until I had cause to leaf through the Annual Review 2010 published by Metlink, the marketing organisation for Melbourne’s train, tram and bus operators.

This claim really caught my attention: “Metlink research shows that 74% of Melburnians use public transport to get to work, school or leisure activities”. Three quarters of Melburnians?! That’s not merely astonishing, it’s mind-boggling. It comes as quite a surprise to me, as the Department of Transport’s VISTA database says that only around 11% of all weekday travel in Melbourne is by public transport and even in the case of education, only 25% of trips to primary, secondary and tertiary education are made by public transport.

That quote can’t be dismissed as a one-off case of excessive zeal. This recent press release by Metlink also seems to strain credibility. It says Metlink has done a survey which found that “19% of Melburnians decreased their car use” in the past twelve months. It goes on to say that “62% of Melburnians (say) they will rely more on public transport than their cars” in the future. And this media statement released the same day says: “The study found that 94 per cent of Melburnians want governments to spend more on public transport……while only 68 per cent wanted taxpayer money spent on roads”.

If some of that sounds improbable, that might be because it is. One clue is in this story in The Age. The reporter, when noting the claim that 19% of Melburnians decreased their car use, also mentions that another 19% increased their car use i.e. Metlink’s survey found net car use was actually static. The reporter also asked Dr Paul Mees of RMIT for comment on another finding  – that the number of people walking more often in the past 12 months increased by 15%:

Dr Mees said he was sceptical about the dramatic jump in the number of people who claimed to be walking more, because if the 15 per cent rise were true, it would be unprecedented. ”I do feel that many people must be responding with the answer that they think the person asking the question wants to hear – it makes them feel good to answer that they are walking more,” Dr Mees said.

Intrigued by the apparent ease with which Metlink can conjure paradigm-changing numbers, I did a bit of digging around and came up with Metlink’s media kit for the survey. As is often the case with chook food, this is mainly Powerpoint slides rather than  comprehensive details about the methodology. Even with that caveat, the material suggests a few possible explanations for Metlink’s somewhat optimistic findings.  Read the rest of this entry »


Is living at density the same everywhere?

A reader, Ian Woodcock, took me to task yesterday about my post on whether outer suburban families would willingly choose densities of 25-30 dwellings/Ha so they could walk to local shops and services.

In particular, Ian reckons I invoked a straw man when I argued that “it can’t be assumed that merely increasing outer suburban housing density will create an environment with the ‘buzz’ and ambience of a St Kilda or Fitzroy”. He says the relevant comparison:

is not with inner-suburbs like St. Kilda that have the highest density in Australia (!), but with the streetcar (tram) suburbs of the inner-middle ring, like Kew, Camberwell, Malvern, Armadale, etc. where densities are higher than the outer suburbs in many places, public transport is good, there is housing diversity and access to a wide range of shops and services, and moreover, social capital is high.

Ian’s broadened the discussion beyond walkability to the merits of density more generally. I’m not sure there are substantial parts of suburbs like Camberwell with average densities as high as 25-30 dwellings/Ha, but nevertheless I’m happy to make the comparison with them. I’ve set out my argument about the attractiveness of higher densities to Growth Area residents below:

My contention is that living in a townhouse or apartment in the inner or middle suburbs – whether it be St Kilda, Kew, Fitzroy or Camberwell – delivers an entirely different set of benefits than it would in the outer suburbs. In essence, it’s worth choosing to live in a town house in the former but not at present in the latter.

Camberwell residents who can afford it generally choose to live in bigger dwellings, usually a detached house with a yard. The rest live in smaller dwellings like newish apartments and townhouses because that’s the only way they can afford to live there. They want to live in Camberwell for all the usual reasons – it’s close to the city centre, close to large centres like Glenferrie Rd and close to private schools. They also like it for the status it confers and because it’s ‘people like us’ i.e. wealthy or aspiring to be wealthy.  As Ian says, it also has good public transport and a wide range of services. But most of those who live in apartments and town houses do so because they have to – it’s primarily about location, not dwelling type.

Some will argue there are people who could easily afford a big dwelling but actively prefer a small one. Undoubtedly there are some, but there aren’t many and they’re not usually families (who’re the main household type in the Growth Areas). The fact that empty nesters tend to hang on to their large houses signals that, if they can afford it, people put a high value on space. People who can afford it don’t buy studios or one bedroom apartments in Docklands or Southbank – they buy three bedroom units and penthouses. All those renovated and extended terraces and houses in the inner city don’t say “small is better”. Location and dwelling size are what economists call superior goods. As incomes rise, consumers tend to buy more of them – they might move to a better suburb or a bigger dwelling (although only the very rich can usually do both).

Now compare Camberwell to the Growth Areas. In the latter a detached house with a garden costs much the same as a townhouse. Households don’t need to forego space in order to live there, so why would they choose to buy a townhouse? Read the rest of this entry »


Should fare zones be rationalised?

I like the principle underlying Melbourne’s two zone public transport fares system – if you travel further, you pay more. Travel within roughly 11 km of Flinders St Station is a Zone 1 fare and travel within the area beyond that is a Zone 2 fare. Those who travel between zones pay a Zone 1-2 fare. Sensibly, there’s a three station ‘grace’ overlap between zones.

The logic of the tariff is premised on the idea that trips are to the CBD. If you live in Epping (say), you are 19 km from the CBD and in Zone 2, whereas someone living near Bell station in Preston is only 9 km out and is in Zone 1. The standard Two Hour Zone 1 fare is $3.80 and the Zone 2 fare is $2.90. If you cross zones, the fare for the longer distances expected with Zone 1-2 trips is $6.00.

That all sounds good, but inevitably there are anomalies. For example, a traveller boarding a train on the Epping line at Reservoir station can travel through 15 stations to Flinders St for a Zone 1 fare. However anyone boarding at the next station out, Ruthven, must pay a Zone 1-2 fare to travel to Flinders St.

Residents who live near the overlap stations and make short trips face a very high marginal cost. For example, someone boarding at Bell station on the Epping line can only travel 3 stations away from the CBD before incurring a Zone 1-2 fare.  Similarly the four station inbound trip from Ruthven station to Bell is a Zone 1-2 fare. The same pattern happens on other lines.

Another anomaly is the cost of Zone 1-2 fares compared to Zone 1 and Zone 2 fares. With so much of the cost of operating a rail service tied up in capital items, it’s hard to see why a Zone 1-2 fare costs 60% more than a Zone 1 fare and over 100% more than a Zone 2 fare. That might possibly make sense for buses but seems a real stretch for trains.

These sorts of anomalies could be seen as unfortunate but inevitable compromises – after all, most travellers are bound for the city centre. However as discussed here, the great bulk of jobs are now in the suburbs, not the CBD. Moreover, most Melburnians live relatively close to their key travel destinations, usually in the same or a contiguous municipality.

We should expect that public transport travellers will increasingly be seeking to make intra-suburban trips via a grid of well coordinated train and bus services. Indeed, many advocate such an approach. A two-part tariff based on distance from the CBD makes less sense in that situation. While the CBD will remain the main market for trains for a considerable time yet, they nevertheless are likely to have a growing role in intra-suburban travel. Policy-makers should be thinking about how to make them work harder in this role. Read the rest of this entry »


Why do we dislike buses?

Houston, we have a problem...

Melburnian’s seem to love trains and dislike buses. Melbourne Airport and Doncaster are both served by high-frequency bus services with a wide span of operating hours, yet large numbers of people want to spend billions replacing them with trains.

The list of criticisms of buses – relative to trains – is long. Right at the top is slowness. Buses operate in traffic, follow circuitous routes, stop frequently and idle while passengers dig out spare change to pay the driver. They’re uncomfortable too. Shelters are perfunctory, the ride is jerky and difficult if standing, seats are jammed too close together and too many drivers don’t seem to actually like passengers. And buses are unreliable. They’re invariably late and if you miss one the wait for the next one will seem interminable. If it’s night or a weekend there’s a good chance that was the last bus for the day.

Then there are systemic criticisms. Buses aren’t ‘legible’ — prospective passengers can’t see where the route goes. Sometimes routes vary over the course of a day. Buses are also impermanent. Developers are less inclined to risk investing along a route if it can be changed overnight or even removed. And there’re hard-nosed criticisms, too. Buses don’t carry many passengers. Operating costs are high because each vehicles requires a driver. Per capita GHG emissions and energy consumption are no better than cars. Engines are noisy and polluting.

As things stand, buses look pretty bad compared to trains, even given the unreliability and crowding that characterises peak hour train services in many Australian cities. Buses have a serious image problem, not just here but in many western cities.

But it’s an unfair comparison*. The key reason buses are perceived so poorly relative to rail is they are mostly assigned to marginal routes with low patronage. Operators follow indirect routes and stop frequently to maximise revenue; they reduce frequency and hours of operation to minimise costs. They can do that because their customers aren’t usually sophisticated CBD workers but travellers who are mostly “captive” to public transport. In other words buses mostly operate in a different market to trains. But it’s given them a bad reputation.

Most of the criticisms can be fully addressed, or at least softened, when the comparison is like-for-like i.e. when buses operate the sorts of long-haul commuter services that urban rail is customarily used for in Australia. Bus Rapid Transit (BRT) systems typically have high patronage and operate in their own right of way (just like trains) or in dedicated on-road bus lanes. Stops are major interchanges spaced kilometres apart and tickets are bought before entry.

BRT vehicles can be made with the internal look and ‘feel’ of (light) rail and the jerky ride can be minimised with electric engines. Articulated buses carry large numbers of passengers and can provide better leg room. According to Corinne Mulley, Chair in Public Transport at Sydney University, Brisbane’s South East Busway carries 15,000 passengers per hour and in Bogota buses carry 45,000 per hour.  She says “US evidence points to infrastructure costs for dedicated buses being approximately one third of light rail costs”. As a point of reference, Eddington forecast that a Doncaster rail line would carry up to 12,250 one-way trips per day. Read the rest of this entry »


Why are we still so focussed on CBD rail?

Bike lanes - Hitler hates them!!

It’s bizarre, but much of the contemporary debate about expanding public transport in Melbourne is focussed on building more rail lines to the CBD even though the great bulk of jobs are now in the suburbs. It seems we’re locked in an old way of thinking when the world long ago moved on to doing things in a very different way.

The proposed Rowville, Doncaster and Melbourne Airport rail lines are evidence of our preoccupation with radial train lines. They were key issues during last year’s election campaign and the Government promised to study the feasibility of all three. They all connect to the CBD. No one refers to any of them as, for example, the proposed “Rowville to CBD” rail line – the debate is so CBD-centric that’s taken for granted.

Yet the city centre now has only a fraction of all jobs in the metropolitan area. The traditional CBD – that area bounded by Spring, Flinders, Spencer and La Trobe streets – has just 10% of all jobs in Melbourne, as mentioned here. Even the entire City of Melbourne municipality has only 19% of metropolitan jobs.

But it’s not just jobs (although they’re very important because that’s where rail does best). The vast bulk of travel by Melburnians for non-work purposes – which involves considerably more trips than the journey to work – is also not directed at the city centre. It’s local and over relatively short distances.

One consequence of  this ‘radial thinking’ mindset is the popular sentiment that ‘black holes’ in the network, like Doncaster, have to be ‘filled in’ with new rail lines to the CBD. This is despite the likelihood that the justification for a Doncaster-CBD line borders on the farcical. For example, Eddington estimated that only 8,500 workers living in the municipality of Manningham commute to the City of Melbourne, of whom 3,150 already take public transport (and this was before the new DART bus rapid transit system started!).

With 72% of jobs located more than 5 km from the CBD and 50% more than 13 km, it’s surprising that the focus of public transport expansion isn’t on improving services for cross-suburban travel.  Why, for example, isn’t there more emphasis on improving suburban orbital services and feeder services to major suburban destinations?

The fact is Melbourne’s radial train system was never intended to deliver workers to suburban jobs. The existing rail lines are the ‘spokes’ in a radial system that’s designed for the high peak loadings generated by the CBD. In contrast, economic activity in Melbourne’s suburbs is quite dispersed – no more than 20% of suburban jobs are in the largest 31 activity centres – so something far more flexible than commuter heavy rail is likely to be required. Read the rest of this entry »


How do world transit systems compare?

This is an eye-opener. First thing you need to do is go here where artist and urban planner Neil Freeman has prepared maps of many more cities at the same scale  (none from Australia unfortunately). What these maps show is the enormous variation in the scale and density of different systems. No doubt the artist has had to make assumptions about what to include and exclude*, but this is nevertheless very important information to bear in mind when comparing the performance of Australian rail networks with systems elsewhere.

I think Melbourne’s rail system is a leviathan compared to some of these e.g. the networks in Toronto, Vancouver, Amsterdam, Budapest and Brussels. Note the scale (5 km) beside the map of Toronto above. As a point of reference, it’s about 5 km as the crow flies from Flinders St station to Merri station on the Epping line, Hawthorne station on the Lilydale line and Newmarket station on the Broadmeadows line. Five kilometres is the boundary of the inner city. Read the rest of this entry »


– Are cars the key challenge?

Share of journeys to work by car, 2006 (click). Map from Charting Transport

The accompanying map from Charting Transport shows the proportion of journeys to work in Melbourne’s inner city undertaken by car in 2006 — the rest were by public transport, walking and cycling (note that green denotes a low share for cars and red a high share*).

There is a clearly defined area — the ‘golden mile’, bounded by Spring, Flinders, Spencer and La Trobe — where cars capture less than 30% of all journeys. Around Swanston Street the share of journeys taken by car is as low as 24% (click to enlarge map).

But the really striking thing to my mind is the steep increase in car’s mode share as soon as you move beyond walking distance of the rail loop. You only have to go as far as the northern side of Victoria Parade and that share jumps to 50– 60%. Go toward the Hoddle Street end and it’s more than 70%. Once you get into the suburbs, most employment concentrations have a mode split that is 80% – 90% car.

One interpretation of the data is that sustainable modes are doing pretty well in the golden mile. Another is that they’re not doing well enough – maybe no more than 10% of journeys should be considered the ‘natural’ share of the car in this sort of key business area – and hence there’s an opportunity for public transport to increase its share.

I incline to the latter view, but I think there’s another interpretation of this data that’s arguably more significant. Consider what it takes, in terms of density and transit supply, to get the share of journeys to work by car down below 30%.

The ‘golden mile’ is just 2 km2 out of a built up area of around 2,500 km2 (the entire MSD is over 7,500 km2). That little area is the largest single concentration of jobs, by far, in the metropolitan area. It accounts for 10% of all metropolitan employment and is denser by an order of magnitude than any other activity centre in Melbourne, as exemplified by the number of very tall buildings it contains. And despite its diminutive size, it’s the focus of the entire metropolitan train and tram systems. It’s the ‘hub’ where all the ‘spokes’ meet – a giant transport interchange – and is accordingly, again by an order of magnitude, the most accessible place in Melbourne by public transport.

Yet for all the astonishing advantages of job density and public transport quality, a quarter to a third of all those who work in this tiny area still drive to work. Further, literally within one or two blocks of the rail loop, the car’s share of journeys to work rises to 50% and more, notwithstanding that these near-CBD areas themselves have a job density and level of public transport service that is far higher than the rest of the metropolitan area. And this is the journey to work – the trip most likely to be taken by public transport! Read the rest of this entry »


Is time on transit more productive than driving?

MTR Hong Kong - SRO (photo by M Wong)

I regularly hear the argument that time spent travelling on public transport is more enjoyable and more productive than time spent in the driver’s seat of a car. The public transport passenger can read, study, write, listen to music, play games, talk to others and even think without distraction. The driver, on the other hand, must devote most of his or her attention to the road or else get fined (or worse).

I think this line of argument is ultimately pointless. Both modes have their upsides and downsides in terms of how fruitfully in-vehicle travel time can be spent. Travellers make their choice on criteria that are far more critical than this one. Still, it’s an argument that’s often made so it’s worth looking briefly at the issues.

You can listen to music, podcasts and radio just as well while driving as you can on transit, so let’s scotch that one from the get-go. In fact some people prefer listening over speakers because ear phones can cause fatigue. And far too few smartphones and mp3 players come with AM radio, so if listening to 621 or 774 on the train is your thing then your options are limited. I’d score this one even.

What you can’t do in a car however is use a notebook computer, send text messages, play games or read reports and books, at least not if you’re driving.  Actually notebooks aren’t widely used on public transport in my experience, even on the sharp end of planes, but reading, texting and playing games are certainly a common way to while away the time. It’s neither legal nor practical to do those activities in any meaningful way if you’re driving.

But they’re much harder to do on public transport if you don’t have a seat. On Melbourne’s public transport system that’s by no means guaranteed in rush hour. In places like Hong Kong, Singapore and Japan where public transport is the dominant mode, you don’t necessarily even get a choice (see picture – the priority there is to move lots of people quickly).

But there’s one area where the car has an offsetting advantage – (hands free) phone calls. Drivers can make personal and business calls without sacrificing privacy and without imposing on others. That means they can make more important, nuanced and meaningful calls than they would on a train or a bus. They can communicate more effectively without feeling self-conscious because strangers are listening in. Apart from the odd loudmouth, phone calls on public transport are like text messages – suitable mainly for communicating simple or straightforward information. Read the rest of this entry »


Does driving cost less than transit?

Median journey to work time in Melbourne, by mode, ordered by approx distance of home municipality from CBD (VISTA)

With petrol prices spiking upwards, it’s a good time to examine the relative cost of driving versus public transport. You can save a lot of cash if you’re prepared to live without a car, but you’ll pay in other ways.

According to the RACV’s 2010 Driving Your Dollar survey, it costs $10,668 p.a. on average to run a medium sized car like a Toyota Camry Altise. The cost could be as low as $6,759 p.a. for something small such as a Toyota Yaris or as much as $19,234 p.a. for a behemoth like a Toyota Landcruiser GXL. On the other hand, a zones 1and 2 Yearly Metcard costs $1,859 p.a. for unlimited travel. However ticket outlays need to be adjusted for household size. In my case, my wife would also require a yearly pass and our two children would need travel concession passes. That brings the total cost up to $4,562 p.a., but that’s still considerably less than the Camry’s $10,668 p.a.

Of course many children already have a school travel concession pass. And adults who know they have a limited travel range could probably get by with either a zone 1 ($1,202) or zone 2 ($799) ticket and buy extra daily tickets on those (presumably infrequent) occasions they travel cross-zone. Travellers who use public transport exclusively will in all likelihood spend more on taxis and occasional light truck rental, as well as sacrifice some spontaneity in trip planning, but in cash terms they should still come out well ahead of car owners.

Whatever the overall saving is, it isn’t going to be realised by households who keep their car and simply use it less. The bulk of outlays associated with a car are standing costs like depreciation, insurance and registration. In order to be significantly better off in cash terms, a household either has to lose a second car or decide they can get along without any car at all.

But this simple accounting doesn’t provide a fair comparison. There’s one big difference that has to be taken into account – travel by car is much faster on average than by public transport. The latter is most attractive for work travel, but even then the median journey time in Melbourne is almost double that by car (see accompanying chart). Those longer trip times in part reflect commuters who catch trains from distant places to the city centre. But the main reason is that passengers have to expend time on tasks like walking to the stop, waiting for the service and in some cases transferring between services.   Read the rest of this entry »


Does higher density mean lower car use?

Travel outcomes (Barnes)

Not necessarily – in fact in the US, not even usually!

It’s a truism that denser, more concentrated cities tend to have higher public transport use. Various studies have confirmed this intuition but what is usually left unexamined is the implicit assumption that such cities consequently have lower car use.

This study of 31 of the largest cities in the US found that assumption is not correct. Higher public transport mode share does not translate on average to lower kilometres of travel by car, shorter commutes by car, or lower levels of traffic congestion.

The primary finding “is that land use, at least at the aggregate level studied here, is not a major leverage point in the determination of overall population travel choices”.

Undertaken by Gary Barnes from the Centre for Transportation Studies at the University of Minnesota, the research found that, if anything, “the higher densities that increase transit share tend to increase commute times and congestion levels”.

The main objective of the project was to identify the effect of land use on travel behaviour. Most studies concentrate on the effect of average density on one or two variables, usually transit share and sometimes total kilometres of car travel.

Barnes’ approach was much more extensive. For each urbanised area, he defined 15 descriptors of travel behaviour, 11 of land use and 15 other, mainly demographic, factors. Moreover, he employed the concept of ‘weighted density’ (he calls it ‘perceived density’) to more accurately describe the distribution of both population and employment in each city.

Barnes confirms that residential concentration increases transit’s share of travel, but he notes the effect is not large. Contrary to the underlying assumptions of much urban policy:

Even very large changes in land use have very little impact on travel behaviour, in good ways or in bad. Apparently the larger effects sometimes observed in neighborhood-scale studies are just that: neighbourhood-scale effects that do not extend their benefits to the larger urbanized area.

His analysis implies that increasing residential density by 100% would increase transit share by only 5-6%. To get a 1% increase in walking and cycling’s combined mode share would require an increase in residential density of 5,000 persons/mile2 (1,931/km2). Similarly, a 14% increase in density would only yield a 0.5% decrease in in-car travel time per person. Read the rest of this entry »


-Sydney buses from the air

Melbourne data visualisation company, Flink Labs, has produced another excellent transport animation – this time it’s 24 hours in the life of Sydney buses. Flink Labs prepared it as part of the apps4nsw program.

There’s also an associated real time bus map which uses GPS to show the location of Sydney’s many buses. It’s updated every minute.

Unfortunately it might not work with Internet Explorer (hmmm, Flink Labs must have a very interesting business model – maybe it’s intended solely for smartphones?).

Sure are a lot of buses in Sydney!

Readers might recall Flink Lab’s superb animation of Melbourne’s trains which appeared on these pages in July.

See also these animations of transport in Auckland and Lisbon.


Is public transport ‘CBD dependent’?

Journey to work mode share, Sydney

A recent paper on travel in Sydney illustrates how dependent the CBD is on public transport and, in turn, how dependent public transport is on CBD commuting.

The paper analyses the journey to work in Sydney using data from the 2006 Census. It was undertaken by Blake Xu and Frank Milthorpe of the NSW Bureau of Transport Statistics.

Although the great majority of travel in Australia’s capitals is now undertaken for non-work purposes and is dominated by the car, the journey to work nevertheless remains an important travel purpose.
This is partly because it generates the largest peak in demand and partly because it is the one travel purpose where public transport’s mode share still remains relatively high.

The first chart shows that, as is the case with other capitals, public transport dominates commutes to the CBD in Sydney. It captures 75% of all journeys by Sydney CBD workers, whereas the car only gets 20%. That’s a bit higher than the other capitals but it’s an expected result.

Journey to work, market share by mode, Sydney

However what might surprise is that outside the CBD, public transport’s share is quite small. Only 13% of people who work elsewhere in metropolitan Sydney use public transport to get to work, while 80% drive.

When the CBD and the rest of the metropolitan area are taken together, the mode split for commuting for all of Sydney is 22% for public transport and 71% for car. Despite its high public transport share, the CBD has a small effect on the Sydney-wide average because it only has a small proportion of all jobs in Sydney – it accounts for just 14% of total work journeys.

Public transport patronage grew strongly in Sydney in absolute terms over 1981-06, but car use grew even faster. Transit’s share of work journeys fell from 25% to 22% over the period.

These numbers tell us that public transport is extremely important for the functioning of the CBD. Delivering large numbers of workers to the Sydney CBD in peak hour simply wouldn’t be possible without it. Read the rest of this entry »


Is this a sensible comparison of cars and public transport?

Many readers will have seen this now-ubiquitous chart before – it’s from Melbourne 2030 and has been republished countless times. It shows the proportion of metropolitan jobs accessible within 40 minutes travelling time from different parts of Melbourne by car and by public transport.

I’ve never been happy with this chart because its simplicity is deceptive – I don’t accept the implicit premise that public transport should be judged on the same basis as cars. I’ll come to that shortly, but first there are some technical shortcomings that need to be addressed.

One is that the chart doesn’t say how the data range intervals are determined – are they equal counts? Are they based on a ‘natural break’ in the way the data is distributed? It’s not possible to be confident that they portray the situation with either public transport or cars in as objective a way as possible.

Another shortcoming is that a mere three categories is very limiting. If you live in Sunbury (say), the chart says you can drive to between 3% and 25% of metropolitan jobs within 40 minutes. That’s an enormous range – a factor of more than eight between the lowest and highest values. It’s essentially a useless piece of information. And the maps give a misleading impression of how many Melburnians live in areas with the poorest accessibility. There are very large areas on the fringe that have a tiny population e.g. there is a 9 km wide greenbelt between Melton and Caroline Springs. Much of the outer north east is a catchment area.

Yet even with these technical flaws, there is some intriguing information. For example, the majority of the population can access no more than 2% of metropolitan jobs within 40 minutes travel by public transport. Read the rest of this entry »


What can Sydney teach us about airport rail lines?

Mode share (prepared by ACCC)

There is little doubt that Melbourne Airport needs action to improve land-side access for passengers arriving and departing from the airport.

Many observers argue the solution is a rail line from the CBD to the airport. I think there’s a much bigger picture they’re missing. They would be well advised to look at the Airport Monitoring Report 2009-10, just released by the ACCC (see chart).

It shows that only 39% of trips to Sydney Airport are made by private car (on-airport parking, rentals and kerbside drop-off), compared to 69% for Melbourne Airport. Since Sydney has a train and Melbourne doesn’t, it’s tempting to conclude that a train is the answer to Melbourne’s woes.

However the ACCC’s report says that more people travel to Melbourne Airport by public transport (14% – all by bus) than is the case for Sydney Airport (12% – train and bus).

A key difference between the two airports is that taxis (incl ‘mini buses’) are far more popular in Sydney, where they account for 49% of all airport trips. The comparable figure for Melbourne is just 17%.

Part of the reason for this difference is taxis are more competitive in Sydney against cars and against the train – Kingsford Smith is 8 km from the CBD and hence is relatively central.  In contrast, Melbourne is 22 km from the CBD so taxis are not as competitive with either buses or cars (other reasons for the difference include more tourists at Sydney, as well as higher parking charges).

As I discussed last week, Brisbane’s airport – like Melbourne’s – is also located a considerable distance from the city centre. It might be that the location of both airports on the edge of their respective metropolitan areas – well away from the centre of gravity of population in both cities – is a key reason for their high private car use (and low taxi use).

Yet distance can’t be the whole explanation. The Brisbane airport train only captures 5% of trips and all up, public transport carries 8% of airport journeys. That’s considerably less than either Sydney or train-free Melbourne.

Given the experience of Sydney and Brisbane, it cannot simply be assumed that constructing a rail line from the CBD to Melbourne Airport will inevitably lead to a significant increase in public transport use – at the expense of cars – over and above the already substantial mode share enjoyed by buses. Read the rest of this entry »


An animated map of Auckland’s public transport network

Last year I linked to an animation of Melbourne’s trains system developed by Flink Labs. This one (click on map) shows a day in the life of public transport in Auckland and was developed by Chris McDowell. He says:

The animation begins at 3am on a typical Monday morning. A pair of blue squiggles depict the Airport buses shuttling late night travellers between the Downtown Ferry Terminal and Auckland International. From 5am, a skeleton service of local buses begins making trips from the outer suburbs to the inner city and the first ferry departs for Waiheke Island. Over the next few hours the volume and frequency of vehicles steadily increases until we reach peak morning rush hour. By 8am the city’s major transportation corridors are clearly delineated by a stream of buses filled with commuters. After 9am the volume of vehicles drops a little and stays steady until the schools get out and the evening commute begins. The animation ends at midnight with just a few night buses moving passengers away from the central city. Read the rest of this entry »


Does density matter for mode share?

Mode share vs density (click to enlarge)

The accompanying chart shows how public transport’s share of the journey to work varies with population density across 41 US and Australian cities.

It is taken from the same article that I mentioned in my last post. The authors, Dr John Stone and Dr Paul Mees, find there is only a modest relationship between population density and transit share (R2 = 0.229). They conclude that “higher density across the whole urban region is not the explanatory variable that many might expect”.

Los Angeles, for example, is the densest metropolitan area in the US – denser ever than New York – yet the chart shows public transport’s share of work travel in LA is much smaller than in NY.

If that seems counter-intuitive, your intuition could be right. The chart uses average population density calculated across the entire urbanised area of each city.

While that’s perfectly alright in some contexts, it doesn’t allow for the possibility that public transport’s ability to win travel away from cars is related to the morphology of density – the ‘peaks and troughs’ in the way the population is spatially distributed. It’s possible that the relative proportion of population in high density areas vs low density areas has a greater impact on mode share.

Using average density probably won’t present a serious problem with cities like Atlanta, Austin, Dallas, Phoenix and Portland where the population is overwhelmingly suburbanised at relatively uniform (low) densities. But it could have a big impact on places like New York which have an extensive ring of low density suburbs as well as a high density central region e.g. Manhattan and Brooklyn.

A way of dealing with this issue is to use weighted density rather than average density. This involves weighting the density of each suburb (or other convenient geographical unit e.g. traffic zone) by its share of the city’s total population. So a one km2 suburb with 5,000 residents (say) carries a lot more weight than another suburb of the same area that has only 1,000 residents. Read the rest of this entry »


Will networking make public transport the mode of choice?

What's the biggest danger?

According to a report in The Age last month, new research published in the latest issue of Australian Planner shows that higher suburban densities are not a precondition for vastly better public transport. Reporter Andrew West says:

City dwellers have been presented with a false choice – live in apartments and enjoy good public transport or retain the house and land and rely on cars

The research by Dr John Stone and Dr Paul Mees contends that it is not necessary to intensify land-use across the whole city before significant improvement in both patronage and economic efficiency of public transport becomes possible.

They say the contribution made by urban consolidation “to recent public transport patronage growth is modest and makes little impact on the density of the whole urban region”. Most residents of Australian cities will continue to live in houses and suburban subdivisions that are already built so “alternatives to the car will need to be effective at existing urban residential densities”.

They argue instead for a ‘networked’ model of public transport. Improving the way existing public transport resources are managed – especially by providing higher frequencies and improving coordination between services and between modes – will yield significantly higher transit patronage in the suburbs without the need for broadbrush increases in density.

I’ve argued before that increasing residential density, by itself, will not necessarily increase public transport patronage significantly, much less shift travellers out of their cars in large numbers.

I’ve also argued that there are generally better gains to be had from using existing resources more efficiently rather than relying on strategies based around huge new infrastructure investments or massive land use changes.

And I think the idea of networking public transport is absolutely critical. By embracing transfers, networking provides faster travel paths to all parts of the metropolitan area than is possible by radial routing.

However it’s not obvious to me that ‘networked’ public transport, by itself, would have the sort of major impact on mode share in the suburbs implied by The Age’s report. I can see that it would make public transport much better for existing users and I’ve no doubt it would increase patronage, but I’m not persuaded that it would be enough to address the ‘false choice’ that The Age says Melburnites have been presented with. Read the rest of this entry »


How liveable are our major cities?

How residents of our five largest cities (combined) see liveability

Adelaide is the most liveable capital city in Australia and Sydney is the least, according to a study released earlier this month by the Property Council of Australia.

The Australian reports that Sydney might have the harbour, Opera House and Bondi, but most Sydneysiders live a long way from these attractions in less salubrious places like Liverpool, Strathfield and Penrith.

The Property Council’s study is based on a national sample of 4,072 respondents in the nation’s eight capital cities (with around 600 in each of the four largest cities). They were given 17 attributes of liveability and asked, firstly, to rate them by importance and, secondly, to rate how well their cities perform on each of them. These two dimensions were then combined to produce a ‘liveability score’ for each city.

I’ve taken quite an interest in “liveability” in the past, especially as it relates to Sydney/Melbourne rivalry (e.g. here, here and here), so naturally I had a look at the study.

These sorts of surveys are often problematic and this one is no exception. For example, information on the representativeness of those who actually responded to the survey is scant and some of the attributes are sloppily conceptualised and poorly worded.

So with that caveat, let’s look at what the study found. The aggregate liveability scores of the eight capitals are probably the least useful aspect because the differences are small – Adelaide does best with 63.4 and Sydney does worst with 55.1. Third ranking Melbourne scores 60.9 but sixth ranking Brisbane scores 60.2. Put Sydney aside and there’s not enough in it to be useful.

What’s more interesting is how respondents define liveability. I’ve put the accompanying chart together to show how the five largest capital cities perform in aggregate i.e. Sydney, Melbourne, Brisbane, Perth, Adelaide (you won’t see this table in the Property Council’s report because I had to correct the figures in the Appendix to the report. Also, make sure to have a look at the full text of the questions).

The first column shows how important respondents think each attribute is for liveability (smaller is better). The second shows what proportion of respondents agree that their city exhibits this attribute. Read the rest of this entry »