How commuters got to workplaces in Brisbane, 2006 and 2011

Sat 17 November, 2012

My last post about Brisbane journey to work focussed on where people live. This post focuses on where people work and what modes of transport they use to get there. It covers employment density, mode shares by work locations, and mode shares for people travelling to the CBD.

ABS data about mode shares at work place locations is available for Statistical Local Areas (SLA) in 2006, and for Statistical Area Level 2 (SA2) geography in 2011. These are the smallest available areas in each year, and unfortunately SLA level data was not available at the time of posting for 2011 (to enable a direct comparison on the same areas).

Fortunately for Brisbane, there is a lot of similarity between the two sets of boundaries (some SLAs split, some combined, some restructured).

The following maps alternate between 2006 and 2011 using the slightly different boundaries. You will need to click on them to enlarge and see the animation.

Caution is needed when making inferences when the geographies change as different areas will have different numbers of employees. For example: If two SLAs with 2% and 10% mode shares (in 2006) were combined into a new (2011) SA2 area with 11% mode share (in 2011), it doesn’t mean that mode share actually changed from 2% to 11% in the first of the SLAs. It may be that many more people were employed in the SLA with 10% mode share and actually very little changed overall.

Employment density

Firstly, what does the employment density of Brisbane look like? If I had the travel zone data available (as per Sydney), I’d be able to draw a much higher resolution picture, but for now I will have to suffice with SLA/SA2 employment density:

A lot of the differences you can see between 2006 and 2011 are to do with the change in boundaries, not necessarily changes on the ground. For example, there are many more SA2s than SLAs in the Ipswich area, which has meant the 2011 data shows a slightly dense area in the centre of Ipswich.

Some places where the SLA and SA2s are the same and a change in employment density is evident include reductions in New Farm, West End, Mitchelton, Wynnum, and Chermside West, and an increase in Enoggara.

Mode share by workplace location

I’ve zoomed in on the inner parts of Brisbane so you can see the inner city details for mode shares (apologies for the lack of place names – I figured the numbers showing the mode shares might be more interesting).

First up, public transport mode share:

Public transport mode share was highest in the CBD, then for areas around the CBD and stretching to a little more to the inner south-west. Curiously, public transport mode share was relatively high in suburban Carindale (the patch of yellow turned green in the “middle” eastern suburbs) and Nundah in the middle northern suburbs.

Significant rises in PT mode share were evident in the following places:

  • Fairfield/Dutton Park – which went from 7%/9% to 23%, which is probably related to the Boggo Road busway and green bridge and route 196 BUZ route.
  • Chelmer (6% to 12%) – perhaps related to train frequency upgrades on the line to Darra
  • Teneriffe (10% to 20%) – although it was absorbed into Newstead-Bowen Hills in 2011 the two SLAs combined into one SA2 had a similar number of employees in 2006. In 2011 Teneriffe was served by a new CityCat ferry terminal, and bus services were upgraded (including the CityGlider bus).
  • Kelvin Road – Herston, which went from 14%/16% to 21% (including the growing Kelvin Grove Urban Village and bolstered by the northern busway)

Next is active transport:

There was very little change in active transport mode share by destination. The exceptions were St Lucia (including University of Queensland) which increased from 13% to 16%, and Highgate Hill which went from 9% to 13%. These areas are connected by the new green bridge (buses, walkers and cyclists only) which would have made it easier to reach these places by active transport.

Enoggera records 13% in both 2006 and 2011, which is explained by the existence of a major army barracks there. I’m not sure why the Anstead area had a 15% mode share in 2006 (it was blended out in 2011 with the change of geography).

Finally, here is sustainable transport mode share (public transport + active only transport):

Suburban destinations with high sustainable transport mode share include:

  • Robertson (which includes Griffith University went from 13% to 17%)
  • Carindale (eastern suburbs, 14% to 17%)
  • Taigum/Fitzgibbon (north suburbs, steady 12%)
  • Mount Ommaney (south-western suburbs, 13% in 2006 but unclear in 2011 due to larger SA2)

The significant rises are covered by the discussion above.

Commuting to the CBD

The Central Business District (CBD) is an important destination as it has the highest employment density, and public transport is probably best placed to compete against the car. For this analysis I am defining the “CBD” as the Brisbane City SA2, which is bounded by Hale Street in the west, Wickham Terrace in the north, Boundary Street in the north-east, and the Brisbane River (here is a map). That’s probably bigger than what you might call the core CBD, but unfortunately I cannot obtain 2011 data at a smaller geography.

Brisbane’s CBD accounted for 15.5% of Greater Brisbane journey to work destinations in 2011, and 14.1% of Brisbane Statistical Division destinations in 2006 (Greater Brisbane is slightly larger than the Brisbane Statistical Division). There were 9.5% more journey to work destinations in the CBD in 2011 compared to 2006.

Here’s a map showing the proportion of commuters who had a destination of the Brisbane CBD in 2011 (by home location at SA1 geography):

The prevalence of the CBD as a work destination is almost directly proportional to the distance people live from the CBD, with the notable exception of Springfield in the southern suburbs.

The next map shows the portion of CBD commuters who used public transport in their journey to work (by home location). I’ve only shaded SA1s with 20 or more CBD commuters, which is quite small for calculating mode shares.

Note: I have not filtered SA1s by density on these maps (unlike others), so some low density SA1s to the south-west of the CBD are included in the following maps.

Public transport mode share was particularly high for those further from the CBD (where such a long drive would probably not be fun or cheap). It was lowest around the CBD itself (presumably the locals just walked to work), a few scattered suburban locations, and around the wealthy and low density Pullenvale area to the south-west (served only infrequently by public transport but not that far from the CBD).

Here’s the share of people who only used private motorised transport to commute to the CBD:

Pockets of high private motorised transport mode share include:

  • Hamilton/Albion
  • Bardon
  • Kenmore
  • Fig Tree Pocket
  • Capalaba
  • Gumdale
  • Tingalpa
  • Yeronga
  • Indooroopilly
  • Pullenvale

I understand that many of these are relatively wealthy areas.

Mode shift in journeys to the CBD

How have mode shares changed for journeys to work in the CBD?

Public and active transport increased their mode shares considerably over the 10 years. In fact, the Brisbane CBD had the second highest mode shift to public transport (in percentage terms) of major Australian CBDs (behind Perth, more on that in a future post).

The absolute number of car driver trips fell from 26,397 in 2001 to 23,244 in 2011, while the number of public transport trips shot up from 47,208 in 2001 to 65,570 in 2011 – a 39% increase (a very similar increase to Melbourne and Adelaide). In the same time, South East Queensland public transport patronage grew by 59%.

The vast majority of people who used public transport to commute to the CBD only used one mode of public transport. However, the percentage of people using multiple public transport modes rose from 2.7% in 2001 to 2.9% in 2006 and 3.6% in 2011, suggesting integrated ticketing may be influencing public transport travel behaviour. That said, Brisbane’s CBD still had the lowest rate of multiple public transport mode journeys to work of the CBDs of Australia’s five biggest cities (more on that soon).

 

I’d like to acknowledge Jane Hornibrook for assistance with this post.


Spatial changes in Brisbane journey to work 2006-2011

Sun 4 November, 2012

How have mode shares of journeys to work from different home locations changed in Brisbane? What impact have recent bus service level improvements had?

In my post on city level mode share changes we saw that Brisbane had a 1.2% mode shift to public transport between 2006 and 2011. This post will uncover which areas shifted the most.

The following animations show various mode shares for journeys to work from census collection districts for 2006 and Statistical Area Level 1 (SA1) for 2011. These are the smallest geographies available for each census. All the data is by place of usual residence.

I’ve animated each image to alternate between 2006 and 2011, so you can gaze at them and spot the changes. You’ll need to click on them to enlarge and see the animation.

Public transport

You can mode shift in the inner suburbs, The Gap, the Albany Creek area, around Shorncliffe, the middle southern suburbs (between Yeerongpilly and Woodridge), and the strip towards Shailer Park. Much less mode shift is evident in the outer suburbs, particularly Ipswitch, Victoria Point, Cleveland, and Redcliffe. The Springfield growth area shows higher mode shares than average for urban fringe areas without heavy rail.

Sustainable transport (only)

This map excludes those who used private transport to reach public transport. In most outer suburbs of Brisbane, it seems the vast majority of people are using private motorised transport as part of their journey to work, including to get to train or busway stations.

Train

Significant mode shift can be seen along the Ferny Grove line, the Shorncliffe line, and the line towards Darra. I can see little mode shift on other lines.

There was modest mode shift towards train in the Inala area (near the Richlands rail line that opened in early 2011). Perhaps it will take some time for commuting patterns to change to take advantage of the rail line?

Note that a significant share of people in Springfield used trains. They will be getting a train closer to home when the rail line extension from Richlands to Springfield opens in 2014. It appears that only a few of them got to the train by feeder bus, as the next map shows.

Bus

There was significant shift to bus use in the southern suburbs, particularly around the South East Busway (shown in purple). This busway opened in 2001, but it seems mode shift has continued. There was also strong shift in South Brisbane and the West End (where the high frequency CityGlider bus was introduced), out to The Gap, to the inner south-west, the inner northern suburbs between the train lines, and south through Calamvale (north of Browns Plains, now served by high service “BUZ” bus routes using the South East Busway). There was little shift to using buses in the outer suburbs, other than in the Browns Plains area which is now serviced by BUZ routes.

Ferry

There are some significant changes, particularly around the West End (south-west of the CBD) where ferry mode share collapsed (perhaps due to increased bus service levels and disruptions to ferries following the 2011 floods). Ferry mode share also dropped in the St Lucia area, and for students on the University of Queensland campus. I suspect this might be to do with increased bus service levels.

There was strong growth in ferry mode share in Bulimba (north-east of the CBD), following the reopening of the Apollo Road Ferry Wharf in 2008 (which on these maps seems to have been a success) (Apollo Road wharf is the furthest downstream ferry wharf on the south bank).

Train and bus

Train and bus journeys increased share in many areas around Brisbane (note the different scale). Notable areas include around Ferny Grove, North Lakes, along the Beenleigh rail line, along the rail line to Darra, and in Springfield. However these are all very small mode shares.

Multiple public transport modes

Multiple public transport mode journey origins tend to be fairly scattered, so here is a summary over the Greater Brisbane area (using place of enumeration data and thus losing journeys with ferry + non PT modes):

Integrated fares were introduced in 2004/05 eliminating the fare penalty for changing modes. There was a slight drop in multi-modal public transport mode share in 2006 (compared to 2001), but then a substantial rise by 2011 (faster than growth in single mode journeys). I want to explore multi-modality in journey to work data some more soon. Stay tuned.

Mode shift to public transport overall

Here’s a map showing the overall mode share to public transport in Statistical Local Areas (SLAs), the smallest geography where data is available for both 2006 and 2011 (you’ll need to click to enlarge, and unfortunately my GIS software doesn’t give every SLA a label ).

The biggest mode shifts to public transport on this map are in Pallara – Heathwood – Larapinta (mostly sparsely populated), around Darra-Richlands (where the new train line opened), Calamvale (new BUZ routes presumably), and around the end of the South East Busway.

Pinjarra Hills has a shift but only 139 people travelled to work from this SLA in 2011, so it only takes a few people to register a larger mode shift. And before you get excited about the airport area (Pinenba-Eagle Farm), only 144 people travelled from there to work in 2011. I’ll look at mode share by work location in a later post.

The biggest shift away from public transport was in Yeerongpilly, whilst other SLAs with significant drops include Fairfield, Geebung, Holland Park, and Highgate Hill. Not sure what the reasons might be in those places.

Walking only

There was a slight shift to walking in the inner city areas, notably around Woolloongabba, Paddington, and Wilston. Walking mode share was highest around the CBD, Fortitude Valley, and around St Lucia/University of Queensland (UQ).

Cycling

Cycling has grown rapidly (off a small base), particularly in the inner suburbs include around St Lucia/UQ and West End.

I’m sure other people will find more patterns – please comment on any interesting finds.


Spatial changes in Perth journey to work 2006-2011

Fri 2 November, 2012

How have mode shares of journeys to work from different home locations changed in Perth? What impact has the new Mandurah rail line had?

In my post on city level mode share changes we saw that Perth had a 2.1% mode shift to public transport between 2006 and 2011. This post will uncover which areas shifted the most.

The following animations show various mode shares for journeys to work from census collection districts for 2006 and Statistical Area Level 1 (SA1) for 2011. These are the smallest geographies available for each census. All the data is by place of usual residence.

I’ve animated each image to alternate between 2006 and 2011, so you can gaze at them and spot the changes. You’ll need to click on them to enlarge and see the animation.

(I’ve used a slightly faster flip speed compared to my equivalent Melbourne post. Is this better? Please let me know).

Public transport

You can see dramatic increases in public transport mode share in the southern suburbs, most strikingly around Kwinana, Rockingham, and Atwell/Success/Hammond Park/Aubin Grove (south of Cockburn Central). You would have to say the new Mandurah rail line is fairly transformational public transport infrastructure.

You can also see people moved in near Clarkson train station (south-east corner of the urban block labelled “Clarkson” in the far north) and 29% of commuters nearest the station caught public transport to work (most on the fast train service to the Perth CBD). If Clarkson is supposed to be a transit orientated development with high public transport use, it seems to have been successful. The public transport mode share is extraordinarily high for such an outer suburban area. Note that Clarkson station opened in 2004.

Areas of Perth with little discernible shift to public transport include Ellenbrook, the Forrestfield/Kalamunda area to the east, and Ballajura (north-east of Mirrabooka). These outer suburbs do have bus routes linking them to the centre of Perth, but they don’t exactly get a high-speed run into the city.

Sustainable transport (only)

This map excludes those who used private transport to reach public transport. In the outer suburbs of Perth, it seems the vast majority of people are using private motorised transport as part of their journey to work, including to get to train stations.

[minor corrections to map made 5 Nov 2012]

Train

As you would expect, there is a huge change in the southern suburbs around the new Mandurah rail line.

It is also interesting to see that train mode share was much higher north of Warwick than it is south of Warwick. In fact for the inner suburbs significant train mode shares only showed up in the immediate area around stations. Those further from the train line were a little less likely to use public transport, and were more likely to use buses, as the next map shows.

Bus

There’s not a lot of change across Perth. In particular, there isn’t much change in the middle southern suburbs (between Fremantle and Cannington). That might suggest the net increase in public transport mode share in this area came from people getting to train stations by modes other than feeder bus.

Ferry

I’ve added ferries for completeness. I’m not sure what conclusions you can draw, especially with the change in geographies between 2006 and 2011. Certainly ferries did get used by a group of commuters in the South Perth area to get across to the Perth CBD (note there is no train station in South Perth).

Train and bus

You can see the middle southern suburbs used feeder bus services in significant numbers, though not as strongly around Kwinana and Rockingham (perhaps parking at the station is easier?). Train + bus commuting also grew somewhat in the northern suburbs between Warwick and Joondalup, and west of Stirling.

Mode shift to public transport overall

Here’s a map showing the mode shift towards public transport by Statistical Local Area (SLA), the smallest geography for which results are available for both the 2006 and 2011 censuses.

The biggest mode shift was in Kwinana, followed by Perth – remainder (areas of the City of Perth excluding the CBD core), Cockburn, Canning and Melville – all around the new Mandurah rail line. Just off the map is the City of Mandurah area, which had a 5.7% mode shift to public transport (from 3.2% to 8.9%). Nowhere in Perth did public transport mode share go down, although in Kalamunda it was stagnant at 6.7%.

And before you get excited about Rottnest Island showing a mode shift to public transport, it is simply part of the Cockburn SLA. For the record, only 73 people on Rottnest travelled to work in 2011, 21% by bicycle and 64% by walking only (none by ferry or other public transport).

Walking only

The biggest change was in the CBD, where there is now a significant density of workers living (and thus making it onto the map). Walking to work was largely confined to the Perth CBD, around the University of Western Australia (UWA, east of Claremont), Fremantle, Joondalup, and Claremont

Cycling

Cycling has grown rapidly (off a small base), particularly in the inner northern and western suburbs, south of Fremantle, and around UWA.

I’m sure other people will find more patterns – please comment on any interesting finds.


Spatial changes in Melbourne journey to work 2006-2011

Tue 30 October, 2012

How have the mode shares of journeys to work changed by different home locations in Melbourne?

The following animations show various mode shares for journeys to work from census collection districts for 2006 and Statistical Area Level 1 (SA1) for 2011. These are the smallest geographies available for each census. All the data is by place of usual residence.

I’ve animated each image to alternate between 2006 and 2011, so you can gaze at them and spot the changes. But you’ll need to click on them to enlarge and see the animation.

Public transport

Public transport mode share is mostly up across the board. Some exceptions include:

  • Langwarrin (east of Frankston)
  • Dingley
  • Greenvale
  • Hillside
  • Eastern parts of Rowville

Sustainable transport (only)

This map excludes those who used private transport to reach public transport. It shows that on the suburban fringe, the vast majority of people are still using private motorised transport to get to work. Areas without significant growth include Sunbury, South Morang, Greenvale, Rowville, Berwick north, Skye/Carrum Downs, Mt Eliza, Dingley, areas around the Ringwood-Lilydale rail line, and Westmeadows.

[minor corrections to map made 5 Nov 2012]

Train

Melb train

[minor corrections to map made 6 Sep 2013]

There is growth across mode areas of Melbourne. You can see a massive difference in Roxburgh Park Craigieburn area following the extension of suburban electric services to Craigieburn.

Bus

You can see a substantial increases:

  • in Doncaster area following the introduction of 7 SmartBus routes (including 4 to the CBD).
  • in pockets between the Ringwood and Dandenong rail lines in the middle eastern suburbs. These areas had SmartBus routes introduced in 2002/2005, and perhaps it is taking a while to translate to bus in journey to work.
  • Around Abbotsford/Collingwood, perhaps reflecting increased train crowding and introduction of four SmartBus routes along Hoddle Street creating an extremely frequent service to the city.

Tram

You can see increased mode share across the network, particularly around the outer end of the tram route to Bundoora (zone 2 only in 2006, included in zone 1 in 2011) (but less so in Vermont South).

Active transport (only)

You can see gains in the Brunswick, Northcote, Kew and Foostcray areas.

Walking only

I can see little change between 2006 and 2011, which is in line with little change in the overall share for Melbourne.

Cycling

Cycling continues to grow rapidly in the inner northern suburbs, but also a little to the inner east and inner south.

Train and Bicycle

With the introduction of Parkiteer cages at train stations, was there any increase in the number of people riding to train stations?

The numbers are so small, it is difficult to see spatially, but there was a substantial increase in overall numbers from around 1200 to 1800.

Train and bus

You can see increases around the Dandenong rail line, between the Glen Waverley and Ringwood rail lines, around Werribee/Tarneit, and around Sydenham.

Public transport mode shift by SLA

Here’s a map showing the mode shift towards public transport by Statistical Local Area (SLA), the smallest geography for which results are available for both the 2006 and 2011 censuses.

The biggest mode shifts were in the City of Melbourne, followed by Wyndham – south (Point Cook), South Yarra/Prahran, and Moreland – north. Nowhere in Melbourne did public transport mode share reduce.

I’m sure other people will find more patterns in the maps than I have been able to today. Please comment on any interesting finds. I might come back later and update this post when I have more time.

I will aim to do a similar exercise for other cities soon.


Trends in journey to work mode shares in Australian cities to 2011

Tue 30 October, 2012

[updated December 2012 with more Canberra and Hobart data, and removing ‘method of travel not stated’ from all mode share calculations]

The ABS has just released census data for the 2011 journey to work (amongst other things). This post takes a city-level view of mode share trends.

Public transport

The following chart shows the public transport share for journeys to work for people within Statistical Divisions (up to 2006) and Greater Capital City Statistical Areas (for 2011) for each of the Australian major capital cities.

PT mode share trend

You can see 2011 increases in public transport more share in all cities except Adelaide, Hobart and Canberra. Melbourne grew by 2.2%, Perth by 2.1%, Sydney by 2.0%, Brisbane by 1.1% while Adelaide, Canberra and Hobart dropped by 0.1%.

But there are limitations of this data:

  • Census data is usually available by place of enumeration (where you actually were on census night) and/or place of usual residence. In the above chart the following years are by place of enumeration: 1991,  2001, 2006, 2011. I am just not sure whether the other years are place of enumeration or place of usual residence (ABS were unfortunately not as rigorous with their labelling of data tables in the past). There may be small differences in the results for place of usual residence.
  • The data available to me has been summarised in a “lossy” fashion when it comes to public transport mode share. It means that a journey involving tram or ferry and one or more non-PT modes is not counted as public transport in any of the results (it falls under “other two modes” or “other three modes” which includes PT and non PT journeys). For example, car + ferry or bicycle + tram. That means the true share of trips involving public transport will be slightly higher than the charts above, particularly for Melbourne and Sydney.
  • The 2011 figures relate to Greater Capital City Statistical Areas. For Perth, Melbourne, Adelaide, Brisbane and Hobart these are larger than the statistical divisions used for 2006 and early data. This means people on the fringe are now included, and they are likely to have lower rates of public transport use. So the underlying trends are likely to be higher growth in public transport mode share.

The limitations in counting of tram and ferry trips can be overcome by measuring mode share by workplace location, although I can only get such data for 2001, 2006 and 2011:

PT mode share by workplace trend

These figures are all higher because they include people travelling to work in the metropolitan areas from outside (where PT might have a higher mode share via rail networks for example) and they count all journeys involving ferry and tram. Between 2006 and 2011, Melbourne grew the fastest – by 2.4%, Sydney and Perth were up 2.0%, Brisbane up 1.2% and very little change in Adelaide, Canberra and Hobart.

Cycling

The following chart shows cycling only journey to work mode share:

cycling only mode share trend

(Adelaide and Perth are both on 1.3% in 2011)

Canberra is the stand-out city, owing to a good network of off-road bicycle paths through the city. But Melbourne has shown the fastest increase, going from 1.o% in 2001 to 1.6% in 2011.

Adelaide, Perth, Brisbane and Melbourne had a significant drop between 1991 and 1996, but this did not occur in Hobart, Canberra or Sydney.

Canberra, Melbourne and Sydney have shown the most growth in recent times. Adelaide and Hobart unfortunately went backwards in 2011. I’m not sure why Adelaide dropped so much, maybe it was a product of weather on the two census days?

Here’s another view that includes journeys with bicycle and other modes (by work location, not home location):

Bicycle any mode share

Perth and Canberra had the largest growth in journeys involving cycling and other modes.

Walking only

walking only mode share trend

Walking only rose in all cities 2001 to 2006, but then fell in most cities between 2006 and 2011 (Perth and Brisbane the exceptions). Perhaps surprisingly, Hobart had a higher rates of walking to work than all other cities.

Car

The following chart shows the proportion of journeys to work made by car only (either as driver or passenger):

car only mode share

(both Adelaide and Hobart were on 82.7% in 2011)

You can see car mode share peaked in 1996 in all cities except Canberra where it peaked in 2001, and Hobart where the 2011 result was just under the 1996 result.

Hobart, Adelaide and Canberra had small rises in 2011 (1.0%, 0.4% and 0.1% respectively) while Perth had the biggest drop in car mode share (down 2.6%), followed by Melbourne (down 2.0%), Sydney (down 1.8%) and Brisbane (down 0.9%).

Vehicle passenger

Vehicle passenger by work location

Travel as a vehicle passenger has declined in all cities, suggesting we are doing a lot less car pooling and commuter vehicle occupancy is continuing to decline in line with increasing car ownership. Curiously Hobart and Canberra topped the cities for vehicle passenger mode share.

Overall mode split

Because of the issue of under-counting of tram and ferry data for place of enumeration, I’ve constructed the following chart using place of work and a “main mode” summary:

 

work dest mode split 2001-2011

I assigned a ‘main mode’ based on a hierarchy as follows:

  • Any journey involving train is counted with the main mode as train
  • Any other journey involving bus is counted with the main mode as bus
  • Any other journey involving tram and/or ferry is counted as “PT Other”
  • Any other journey involving car as driver, truck or motorbike/scooter is counted as “vehicle driver”
  • Any other journey involving car as passenger or taxi is counted as “vehicle passenger

In future posts I plan to look at the change in spatial distribution of journey to work mode share (by home and work location).

I’d like to acknowledge Dr John Stone for assistance with historical journey to work data.


What’s driving Melbourne public transport patronage?

Fri 11 May, 2012

[Updated June 2012 to include ratios over time, inner city parking, and other updated data. First posted January 2010]

In this post, I test out a number of possible explanations for the trend in Melbourne’s public transport (PT) patronage growth over recent years to try to find out what might be driving growth. Is it population growth, CBD employment, fuel prices, international students, or the widening of CityLink? You’ll have to read on.

The first chart shows estimated financial year public transport patronage in Melbourne. Note: The method of patronage estimation has changed over the years for all modes. I have assumed comparable measurement for trains and trams and applied my own informed adjustments to bus patronage history (although I am less confident about the early 1990s – officially patronage stayed much the same despite significant service cuts).

Patronage was bumpy in the 1990s, followed by modest growth for about 10 years and then a distinct uptick in growth around 2004/05.

I will attempt to find an explanation for this pattern in this analysis (particularly more recent years). Short of a fully comprehensive analysis, I will compare trends in possible drivers with the trend in public transport patronage.

Note due to the nature of available data sources, the years covered in chart will vary – you can spot each year by checking the year range in the chart titles.

Population growth

If this was a dominant factor then you’d expect to see a straight line on this chart. It does show that as population growth has increased, so has public transport patronage growth, but the overall relationship isn’t very linear. Here’s the ratio of patronage to population for all of Melbourne:

We know that public transport use is higher closer to the inner city of Melbourne. So is public transport better correlated with inner city population? The following charts compare PT patronage with “inner” population (LGAs of Melbourne, Port Phillip, Stonnington, Yarra, Hobsons Bay, Maribyrnong, Moonee Valley, Moreland, Darebin, Banyule, Boroondara, and Glen Eira).

The correlation appears to be slightly stronger, but still not very strong.

Employment

People often use PT to get to work. The next chart compares total employed people in Melbourne to public transport patronage (employment figures average monthly total employed people for each financial year, from ABS Labour Force surveys).

Again, the relationship isn’t very linear – despite a small growth in employed persons in 2008-09, public transport patronage still increased significantly. But then in 2009-10, employed persons grew but patronage didn’t. Likewise PT patronage increased more between 2000/01 and 2001/02, despite little growth in total employment, whereas in the previous year employment grew strongly, but PT patronage didn’t.

This chart also shows kinks in the trend around 2005 and in 2008-09 – so employment doesn’t seem to explain the kink. Note also that journeys to work only make up around 40% of public transport trips in Melbourne (according to VISTA data). And public transport has a very low mode share of journeys to work outside the city centre.

Here is the relationship shown as a ratio over time:

ABS publish figures monthly, and here’s the picture for total persons employed in Melbourne. There was virtually no growth between late 2010 and May 2012 (at least). There was also a flat patch between the start of 2008 and the middle of 2009 (2008-09 shows substantial patronage growth on public transport).

City population (including visitors)

Another hypothesis suggests that if PT is heavily focussed on the inner city (where it has the highest destination mode share), then if more people need to travel to the inner city, this would probably increase PT patronage. This sounds very plausible, especially for trains and trams. The City of Melbourne has estimated weekday daytime population for 2004 to 2010 calendar years. So I am mixing calendar year visitor data with financial year PT patronage – which is not ideal. Anyway, here is what that relationship looks like:

The year 2005/06 includes the 2006 Commonwealth Games that were held in March 2006 and boosted city visitors considerably. If you take out this anomaly, the other four data points look like they form a very linear pattern (as drawn), suggesting it is quite probably a strong driver. There was weak growth in both public transport patronage and city population in 2009-10, suggesting a strong relationship.

The next chart shows the same relationship as a ratio over time. The 2006 anomaly is much less noticeable (note not a huge variation in weekday daytime population the chart above). This suggests that City of Melbourne weekday daytime population is not directly proportional to public transport patronage (in other words: the y-intercept is not zero).

A longer time series of CBD data is available for  employment, thanks to the City of Melbourne’s Census of Land Use and Employment. As it hasn’t been an annual survey (red dots are census results), I have made linear interpolations between the years for CBD employment numbers.

Between 1997/98 and 2007/08, the trend was remarkably linear suggesting a strong relationship. When CBD employment grew very weakly between 2002 and 2004, so did PT patronage. Looking at census data for 2001 and 2006, we know that PT mode share to the Melbourne CBD for journeys to work (well, technically the inner Melbourne SLA which is much the same) grew only slightly from 59.1% to 60.8%. So it looks fairly safe to assume that the growth in people using PT to get to jobs in the CBD grew at much the same pace as CBD employment itself.

However between 2007/08 and 2009/10 the trend seems very different. Public transport patronage grew strongly even though the number of employees in the Melbourne CBD did not show much growth at all.

Here’s the same relationship expressed as a ratio over time. The ratio is remarkably flat over time.

Employment has grown around the Melbourne CBD in neighbouring Docklands, Southbank and there are also a number of office buildings in East Melbourne. In fact between 2008 and 2010 there were around 3,300 new jobs in the CBD, and 11,400 new jobs in Docklands.

These areas are also well serviced by public transport. Unfortunately data for these surrounding precincts only goes back to 2002. Here’s a chart comparing PT patronage to total employment in the CBD, Southbank, Docklands and East Melbourne for 2002 to 2010:

Suddenly the trend looks a lot more linear, with a deviation only for the interpolated result in 2008-09 (which might be a product of the GFC in that timeframe). CBD employment alone is no longer a strong driver of public transport patronage. Although bear in mind that public transport mode share in these CBD fringe areas was much lower than the CBD in 2006 (see previous post).

Here’s the same relationship as a ratio over time, which is a little flatter:

While the CLUE data series only runs until 2010 at present, a more timely and regular dataset that might be related to CBD employment is occupied office floor space, calculated from the Property Council of Australia’s Office Market Reports. While I do not have access to the reports themselves, much of the data is available on the internet in various forms, and I have used that data to reconstruct the data series (there is chance of errors creeping in, particularly for earlier years).

Here is the trend in occupied Melbourne CBD office space:

Slow growth until about 2005, then very strong growth. Does that trend sound familiar?

This charts shows very strong correlation (r-squared = 0.99). Although there are still a few small kinks such as 2009-10.

Here it is as a ratio over time, which is not entirely flat:

But the overall strong relationship this confirms the high likelihood of CBD employment being a very significant driver of public transport patronage. Ideally Southbank, Docklands and East Melbourne should be added to the mix, but the data is not readily available.

Inner city parking

A commenter on this blog suggested I look at parking in the inner city. The following chart looks at public transport patronage and total commercial parking spaces the CBD, Southbank, Docklands and East Melbourne.

Between 2004 and 2006, commercial parking spaces grew strongly, while public transport patronage did not. Then public transport patronage grew strongly and there was actually a decline in the number of commercial parking spaces.

I would expect the price of parking to be a stronger driver of public transport use than the capacity available. Unfortunately I do not have a long enough time series of parking prices to test this hypothesis. See also my post on the Melbourne CBD.

Fuel prices

I have taken the monthly average unleaded fuel prices for Melbourne, adjusted for CPI, and then averaged the months for each financial year, to produce the following chart:

Fuel prices are highly volatile, even on an annual basis. Again, even though fuel prices dropped in 2008-09, PT patronage still increased. There seems to be a lot more at work than fuel prices. That said, since 2004-05, real fuel prices jumped from around 115 cents to over 130 cents and have remained higher since. So fuel might be an explanation for the kick up in PT patronage since 2005, perhaps more as the breaking of a psychological price barrier. Or perhaps people’s responses to fuel prices have longer lag times that wash out short-term fluctuations – as people make major decisions – such as the decision to purchase a new car or not. More on that later.

International students

Another hypothesis is that the recent boom in international student numbers drove public transport patronage, as many international students come from countries where public transport is the “default” mode. And while their finances might stretch to studying in Australia, it might not stretch to owning a car (certainly in the car ownership maps we see low car ownership around many universities).

Unfortunately I’ve only found complete data for financial year 2002/03 onwards, and only at the state level (more detailed data is not freely available).

The boom in international students looks like it really took off in 2007, but fell away sharply in 2009-10 and has been lower since. In 2009-10 patronage grew more slowly, perhaps reflecting the drop in international student numbers. But 2010-11 patronage growth was strong again, despite little growth in international student numbers.

The international student numbers are very small in comparison to the total patronage. However if half of those students averaged 10 trips per week for say 40 weeks a year (purely a guess), that’s 38 million trips. I’ve not got data on what their PT use is actually like (I suspect many live close to their school or university and actually walk). And their boom doesn’t coincide with the boom in public transport patronage that started around 2005. So they might be having an impact – hard to conclude much.

Road congestion

Until 2006-07 there was a fairly linear correlation, but then speeds only slowed slight while public transport patronage increased. In 2009-10 speeds increased and public transport patronage grew slowly. Perhaps congestion wasn’t a driver for patronage growth in 2009-10?

Another point to note is the scale on the X axis – the average speed hasn’t changed by very much. Although the variations in AM peak speeds for particular road segments are likely to have changed more significantly, I somewhat doubt whether the average driver would notice the difference between 35.8 km/h and 34.8 km/h (the change between 2005/06 and 2007/08).

The opening of CityLink in 2001 may have led to a slight increase in AM peak speeds, but this seems to have been quickly eroded the following year (so do new freeways ease congestion?). I’m not sure why traffic sped up in 2003/04, but then dropped again significantly the next year.

Road congestion impacts the majority of the tram network, and essentially all of the bus network. So perhaps only trains are attractive as an alternative to driving in congested traffic. Here’s same chart again but plotted only against train patronage:

The chart looks much the same. So congestion might be a driver of PT patronage growth, but it probably doesn’t explain the growth in tram and bus patronage, and the relationship isn’t nearly as linear as other factors.

Perhaps also at play here is congestion being relieved for non-radial commuting, where PT had a low market share beforehand anyway. Further research might look at congestion on CBD-radial roads only, though even then, many will also cater for some cross-city trips.

Two of the radial freeways that feed inner Melbourne are operated as the CityLink toll roads, and quarterly data is available on average daily transactions. If the CityLink toll roads compete with public transport it is probably mostly with trains for longer distance travel to the inner city. Here is a chart showing growth in CityLink transactions and train patronage:

There was very little train growth in the first few years of CityLink (which started in 2001). But then train patronage grew strongly from 2005 while CityLink transaction growth went flat until 2010. A major upgrade project on the eastern leg of CityLink (M1 upgrade) caused delays between 2007 and early 2010, and there was little traffic growth. After the project was largely completed and the fourth lane opened, traffic growth accelerated over 2010. This happened at much the same time that trains recorded weak patronage growth. Then in 2011, train patronage grew again, while traffic seems to have flattened again.

To take a closer look at the two growth rates, here are financial year growth rates on CityLink and trains:

After most of the works were completed, CityLink transaction growth exceeded train patronage growth in 2009-10 and 2010-11 (note that the flattening evident in the previous chart doesn’t show with annual data). The evidence suggests there could well be a relationship between freeway capacity and train patronage, and that the M1 widening project may have reduced patronage growth on the train network. It has certainly enabled a return to strong growth on CityLink.

Car ownership

People who don’t own cars are probably much more likely to use public transport. The following chart uses cars per 100 persons aged 20-74 (as a proxy for people of car driving age).

This chart shows in the early 2000s that car ownership rose quickly, while public transport patronage growth was slow. Then from 2006-07, car ownership levels peaked and public transport patronage grew quickly. Car ownership dropped in 2008-09 just as public transport patronage surged, but recovered in 2009-10, as public transport stalled. This suggests there may be some relationship between PT patronage and car ownership, but the annual change rates aren’t always consistent.

Service kms

Another potential driver of PT patronage is the amount of service provided. Thankfully, this data is available in Victorian State Budget papers (hidden away in budget paper 3) on the number of timetabled service kms for each mode. As the modes are quite different, I’ve plotted modal charts:

Train patronage doesn’t seem to be very strongly related to timetabled kms. Perhaps this is because the service levels at peak times on most lines are already attractive from a frequency point of view at least. Many of the extra train kms are providing capacity without a substantial jump in frequency (although some of the additional kms have been in off-peak periods).  That’s not to suggest there isn’t a relationship, just that it doesn’t look likely to be the dominant driver. In the early 2000s it seems that there wasn’t a strong response to increased timetable kms (including Sydenham electrification in 2002), while in the mid 2000s patronage grew despite kms staying much the same (other factors must be at work).

Again, not a strong relationship between tram kms and patronage, despite strong growth in timetabled kms in the early 2000s (partly from tram extensions into lower density suburbs in 2003 (Box Hill) and 2005 (Vermont South) – see here for more history). It also looks like some cuts in 2000 (when some city routes had to be joined due to the loss of W class trams) were done in a way that didn’t result in a loss of patronage. Perhaps because service frequencies were still fairly good after the cuts.

There does seem to be a stronger relationship between bus kms and patronage. This is perhaps to be expected as bus service levels are on average very low in Melbourne, so improved service levels are likely to result in existing users travelling more, and better attract new users.

What is unexpected is that patronage grew at much the same rate as kms between 2005-06 and 2009-10 – an average elasticity of around 1, which is much higher than you would normally expect. In 2010-11, the annual elasticity fell to 0.42. One possible explanation for the slightly steeper rate in recent years is that more of the new kms have come in the form of SmartBus kms (with higher frequencies). We know that long run implied service elasticities for SmartBus can be around 2 – which is higher than the textbook expectation of service elasticities of up to 1 in the long run. Bus upgrades in the early 2000s were a little more focussed on providing new low-frequency services to the urban fringe, which would be unlikely to lead to as much patronage growth.

Here’s a chart showing the ratio of patronage to service kms for all modes:

This chart shows increasing intensity of use of trains and trams between 2004 and 2009, while buses have remained around 1.0-1.1 boardings per service km for at least 12 years running. The significant difference between trams and buses is best explained by the territory covered: trams mostly the CBD, buses mostly not the CBD.

Comparing annual growth/change rates

The following table shows the annual change in Melbourne public transport patronage and a number of potential explanatory factors. I’ve used conditional formatting such that darker green cells indicate values you might expect to contribute to strong PT patronage growth. Rows that have dark green in the same years as PT patronage are potentially stronger at explaining the trends in public transport patronage. I’ve also included the r-squared value for a correlation for each factor compared to PT patronage (based on annual growth rates, not actual values). You might need to click to enlarge and make it easier to read.

The table confirms a strong correlation with CBD+fringe employment, City of Melbourne visitors (2006 removed due to Commonwealth Games anomaly), international student enrolments, population (particularly inner city), and CityLink volumes.

Fuel prices don’t show a strong relationship, although it is hard to believe that they would have no impact. If you offset the fuel price changes by one year the correlation rises to 0.3 so there might be some lag involved.

Conclusions

Based on these simple charts, I surmise that City of Melbourne (LGA) visitations is likely to be one of the strongest drivers of overall PT patronage in Melbourne (but certainly not the only driver). And it certainly stands to reason, given PT’s dominant mode share of travel to the inner city.

But international students, radial motorway traffic volumes, population are probably also having an impact. The impact of fuel prices appears to be more complex.

Buses probably show less response to growth the inner city travel market (as most do not serve the city centre), so service kms are likely to be the strongest driver of bus patronage.

The PCA’s Office Market Report provides the most timely and frequent data relating to CBD employment growth and reveals much slower growth over calendar 2011 (1.4% in occupied office floor space). We might find this trend reflected in slower patronage growth on the train network as  figures are published.


Trends in transport greenhouse gas emissions

Fri 4 May, 2012

[Updated in June 2015 with 2013 inventory data. First published May 2012. For some more recent data see this post published in December 2018]

Are greenhouse gas emissions from transport still on the rise in Australia? Are vehicle fuel efficiency improvements making a difference?

This post takes a look at available emissions data.

Australian Transport Emissions

The Department of Environment’s National Greenhouse Gas Inventory reports Australia’s emissions in great detail, and 1990 to 2013 data was available at the time of updating this post (there is usually more than a year’s lag before this data is released).

More recent but less detailed data is available in quarterly reports and here’s what the rolling 12 month trend looks like up to September 2014:

transport emissions quarterly 2

Emissions have grown by 50% since 1990, although a peak was experienced in the 12 months to December 2012 with a slight decline since then.

Transport was responsible for 17.2% of total Australian emissions in the year to September 2014 (excluding land use), an increase from around 15% in 2002.

Here’s the make up of those emissions to 2013:

Australia Transport Emissions 3

Road transport contributed 84% of transport emissions in 2013 (down slightly from a peak of 89% in 2004). Cars accounted for 48% of Australia’s transport emissions in 2013, down from 57% in 1990.

Note that the above chart does not include electric rail emissions (see below), indirect emissions, or emissions from international shipping and aviation. Estimates for these are included in the following chart lifted from an 2008 ATRF paper by BITRE’s David Cosgrove. It shows this components add a lot on top (and the future projections are frightfully unsustainable). International transport emissions seem to sneak under the radar in the published figures.

Per capita transport emissions

The following chart shows Australian transport emissions per capita have been fairly flat at around 4 tonnes per person since around 2004:

Australia transport emissions per capita 3

To put that in context, 4 tonnes per capita is just above Romania or Mexico’s total greenhouse gas emissions per capita (from all sectors, not just transport).

An aside on electric rail emissions

Electric rail emissions are included under stationary energy, rather than “transport” in the main inventory. Melbourne train and tram electricity emissions have been estimated at 505 Gg for 2007 (ref page 8). Apelbaum 2006 estimated that Australia electric rail emissions in 2004/05 were 2,082 Gg (ref page 68), which is very similar to the inventory figures. I’ve struggled to find any other figures on electric rail emissions in the public domain.

Sectoral growth trends

Transport is now Australia’s second largest emissions sector (after stationary energy), and transport has had the highest rate of emissions growth since 1990:

Australia emissions growth by sector 2

Within the transport sector, civil aviation has had by far the strongest growth since 1990 (but note this comes off a low 1990 base as airlines were recovering from the 1989 pilot’s strike). There’s been a lot of growth in light commercial vehicles, trucks and buses, and in more recent times, railways. Emissions from cars are continuing to grow, while domestic marine and motorcycle emissions have fallen (there appears to be a lot of fluctuation in the motorcycle estimates so I’m not sure I’d read too much into the movements).

Australia transport emissions growth by sector 2

Road transport emissions by state

The national inventory data allows us to see what is happening at a state level. Here is a chart of road emissions by state:

Australia Road Transport Emissions 2

The quantities largely reflect the sizes of each state, but here are the growth trends since 1990:

Australia Road Transport Emissions growth by state

Queensland and WA have grown the fastest by far, followed by New South Wales and Victoria.

The following charts remove the impact of population growth on trends by showing emissions per capita figures for each state. Some states appear to be declining while others appear relatively static.

Australia Road Transport Emissions per capita 2

Car emissions reductions – mode shift or fuel efficiency?

The following chart shows car emissions per capita (which essentially removes freight from the road transport figures).

Australia Car Emissions per capita 2

Again, all states show a decline in recent years.

So is the drop in road transport emissions related to behaviour change and/or fuel/emissions efficiency?

The following chart shows that the average emissions per km of Australia cars was trending downwards until around 2007 but has since increased (I’ve used BITRE 2014 Yearbook data on car kms travelled hence a little noise):

car emissions per km 2

Since 2007, car emissions per capita have been declining, but car emissions per kilometre have not – suggesting the reduction in emissions would be primarily due to changes in travel behaviour, not improvements in engine technology (or at least that improvements in engine technology are being cancelled out by us buying cars that are heavier and/or that have more energy intensive features).

What about transport emissions in cities?

As part of the Victorian Transport Plan, the Victorian Department of Transport commissioned the Nous Group to do a wedges exercise on Victorian transport emissions. This report included estimates of Melbourne’s 2007 transport emissions (12,270 Mt). In addition, Apelbaums’s Queensland Transport Facts 2006 was for a brief time on the internet and I was lucky enough to grab a copy. From that report, estimates of Brisbane’s 2003-04 transport emissions can be derived (7,312 Mt).

The breakdowns are remarkably similar:

What does this look like per capita? I’ve also added London and Auckland figures (though I am not aware of the make up of the Auckland data) to create the following chart:

Obviously these cities’ transport systems and energy sources are very different, but it shows what is possible even for a large city like London. Transport emissions will closely follow transport energy use per capita, which has been the focus of a lot of research, particularly by Prof Peter Newman (eg his Garnaut Review submission).

For 1995 measures of passenger transport emissions per capita for other cities, see this wikipedia chart created using UITP Millenium Cities Database for 1995. Note: these figures only include passenger transport and hence are different to the above.

Also, here is some data for US cities from the Brookings Institute, but it excludes industry and non-highway transportation so is not comparable to the above chart.

Where are transport emissions headed?

Numerous projections of Australia’s domestic transport emissions have been made over recent years, as summarised by the following chart:

Australian transport emissions reported and projected

We appear to be tracking fairly closely to the 2007 projections. The 2010 projections anticipated a reduction in emissions per kilometre travelled, which has not eventuated, as we saw above.

Note the 2015 projections do not include abatement measures – no prediction was made about the effect of abatement measures of which there are few in the transport space of which I am aware.

The only projection that included a decline in transport emissions was a 2012 scenario including a carbon price, which has since been abandoned by the Abbott Government.