Abstract: 2010 PIA Queensland Conference Title The 30 minute city Author name(s). Sigrid Sanderson PIA membership grade (if a PIA member). Company membership - Affiliations Contact details: Addresses, phone numbers, fax numbers, and email addresses. Sigrid Sanderson Director of Strategic Planning and Economic Development AECOM Sigrid.sanderson@aecom.com Level 8 540 Wickham Street Fortitude Valley Ph: 3553 4076 Fax:3553 2050 Mob: 0401 719 733 Whether the submission is refereed or non refereed (refereed papers are academic papers). Non-refereed 3 4 line description for promotional purposes. Sigrid Sanderson is the director of strategic planning and economic development for Queensland s AECOM office. Sigrid has spent in time Melbourne, Sydney and Perth driving the agenda of good transport planning to assist in shaping a city. Audio visual requirements. Projector for powerpoint or PDF
Introduction The concept of a 30minute city attempts to link the ideas of travel time and land use. Traditionally cities have developed land use plans and transport solutions in isolation. Whilst the idea of integrated land use transport planning is espoused there is very little research that links the practicalities of the two. Transport is often described as a derived demand suggesting a predict and provide approach to infrastructure however there is significant historical evidence to suggest that good land use planning is enough to drive transport outcomes. The concept of a 30 minute city plays on the journey to work as the primary trip movement that influences the choices that households make in terms of job and home location. There is significant research to suggest that the journey to work is an influence however the impact that the journey to work has on the building form that occurs within cities is limited. Other factors also shape decisions on desirable locations to live and work such as job availability and housing affordability and these also need to be considered when determining built form outcomes. However, if a 30 minute travel time catchment were used as a planning rule of thumb to assist in supporting land use and density decisions, our cities would move part way towards meeting community expectations for liveability. Historically cities have developed in response to the 30 minute travel catchment. Medieval cities were built around a walking catchment. They were small compact and responded to the travel needs of the residents. As transport travel distances increased (but not travel times) with the advent of rail and later the motor vehicle, the shape of traditional cities including Brisbane changed. We now have a situation that travel time again has the ability to change housing expectations and product as congestion starts to influence the shape of the 30 minute travel time catchment. This paper attempts to support planning for 30 minute cities by relating mode travel times to densities as an ideal outcome would be to have the majority of the population able to live within a reasonable catchment of their place of employment. Where there are centres and clusters of jobs the density catchments and transport provision needs to respond accordingly. Figure 1 shows diagrammatically the concept.
Figure 1: The T 30 minutte city In relatingg density to trravel time, co omparisons haave been mad de between B Brisbane and European cities (Rom me, Athens, Barcelona, B Berlin, Manchesster and Milan) that all havve a similar population p to central Brisbane. The comparison c also indicates the t influence e that history has had on city density with manyy of the Europ pean cities haaving medieval walking cattchment origins. The Journ ney to Work Travel Tim me The conce ept of 30minu ute travel time is based on the many ind dicators that support liveable city frameworrks. When con nsidering average and meaan travel timees for journeyys it becomess evident thatt the 30min nute rule of th humb is an ap ppropriate ind dicator of travvel time acceeptance. An Australian A survey of time t use conducted by thee Australian Bureau B of Statistics found that the averrage time spent travvelling to and from work was w 21 mins however for males m this wass 27 minutes and for females 14 4mins. The differences d arre probably an n indication of o householdss where men are the primary workers w travellling to the citty whilst wom men work closser to home. When consid dering only full time employment the travel t times increased for males to 44 minutes m and ffemales to 24 4 minutes. Full time employment is more likely to influence hou using location as it tends to o have a greater perceptio on of perman nency. In comparrison, averagee commuting travel times for European n countries (data on speciffic cities was not available) tend to be b greater but still around the 30 minutte timeframees. Similar studies of American cities also ind dicate a 30 minute m travel ttime.
Table 1: Time spent commuting City Travel Time (mins) Italy 23 Spain 33 UK 45 (1) Portugal 33 Austria 36 France 36 Source: European Foundation for the Improvement of Living and Working Conditions, Dublin, 1996 Notes (1) It is likely that London heavily skews the average commute travel time for the UK with cities of similar size to Brisbane having a shorter commute travel time Travel Distances and Speeds In order to determine the 30 minute catchment, travel distances and speeds also need to be determined. In Brisbane the average commute distance is around 15.3 km. This is slightly less than Sydney where the average commute distance is closer to 16.8km (1997 Household travel survey). Table 2 indicates that whilst travel distances have been increasing, travel speeds have not suggesting that congestion is currently not influencing travel patterns. Table 1 Average Commute Distance in Brisbane Year Travel Distance Average travel speed on road network 1991 13.7 42 1996 15.0 39 2001 15.2 39 2006 15.3 40 Source: Connecting SEQ 2031: An Integrated Regional Transport Plan for South East Queensland When considering European cities of a similar population to current Brisbane and where the city may be in the future (3 4million) average distances for the journey to work are much lower, by almost 50% possibly as a result of the typically more compact built form developed over time. Many of these cities have developed as compact walking cities. These cities are also typically more congested than Brisbane hence people live closer to be within the 30 minute catchment.
Table 3 Average Commute Distance in European cities of a similar size to Brisbane City Average Travel Distance to Population work (km) Rome 13.2 2,654,000 Athens 8.4 3,682,000 Barcelona 7.4 4,228,000 Berlin 9.8 3,471,000 Manchester 7.0 2,578,000 Milan 7.5 2,460,000 Munich 9.4 2,391,000 Source: Millennium Cities in Study of European best practice in the delivery of integrated transport: report on stage 1 benchmarking In Brisbane average travel speeds are around 40 km/h. In European cities of similar size, the travel speed is much less as shown in Figure 2. Berlin is around 31 km/h whilst Milan and Munich are both under 35 km/h. Manchester is most similar to Brisbane. Travel speed is an indicator of congestion. Brisbane having a travel speed higher than other cities of slightly larger population could suggest that there is spare capacity in the road network for future population growth. It is worth noting that public transport speeds, especially buses are lower than vehicle travel speeds regardless of what city is considered. Figure 2 Travel speeds for 2.5 to 4.5 million population cities 45 40 35 30 25 20 15 10 5 0 Average Network travel speed Bus travel speeds Source: Adopted from Study of European best practice in the delivery of integrated transport: report on stage 1 benchmarking Travel Mode Our value of time has a strong relationship to trip purpose and mode. There is an expectation that community convenience related trips will be shorter (for school, recreation and shopping) however work related trips tend to be longer. Indeed mode has an influence on acceptable travel times. Generally people are more prepared to travel for longer times and associated distances for heavy rail than they are for other forms of public transport as shown in Figure 3. In the European cities mentioned in Table 2, the trend is very different with shorter public transport trip lengths compared
to private vehicle trips. Still however, our choices in house location are very closely linked to employment when affordability is not considered. Figure 3 indicates that we accept longer travel times and distances for heavy rail trips. It is at these distancess that the time competitiveness between public transport and private vehicle is most. Figure 3: Mode share and average travel times for Brisbane Source: Brisbane Transport Data Centre (1999). On average journey to work data for South East Queensland indicates a strong preference for the car. Of all journeys in 2006, 84% were by car, 11% by public transport and 4.6% by walking and cycling. Looking however at the journey to the Brisbane CBD where alternative modes of travel are more prevalent, only 56% is undertaken in a car. Comparing to European cities very different patterns are found where public transport use is much higher. Table 4 indicates the share of passenger km s travelled. The share of public transport trips is most likely a factor of investment in this mode. In Rome, Barcelona, Milan and Munich, annual spend on public transport on a per capita basis is greater than road infrastructure. In Manchester the public transport share of passenger km s travelled is least which is also where congestion is least.
Table 4 Mode share of passenger km s travelled for European cities of a similar size to Brisbane Passenger km travelled per person City Car % Public Transport % Total Rome Athens Barcelona Berlin Manchester Milan Munich 5202 3565 2165 3071 2579 3698 4548 58% 71% 55% 64% 83% 71% 63% 3805 1454 1764 1736 541 1480 2622 42% 29% 45% 36% 17% 29% 37% 9007 5019 3929 4807 3120 5178 7170 Source: Millennium Cities in Study of European best practice in the delivery of integrated transport: report on stage 1 benchmarking History of travel changes in patterns as cities increased in size It is of note to understand the travel distances by mode over time. Work undertaken by BTRE in relation to public transport use suggest that between 1942 to 1982 there was a significant fall in public transport vehiclee kilometres travelled (VKT s) compared to private vehicle VKT s. Considering the travel time and infrastructure response, through this 40 year period the average household car ownership significantly increased along with transport infrastructure and planning for a road based city. In a Brisbane context this was largely influenced by the Wilbur smith transport plan in 1965. The plan was based on the removal of public transport provision with replacement of a network of highways and speed controlled road corridors that sought to increase city size through enlarging the 30minute catchment area. The challenge is to reverse these trends to be more consistent with European cities such as Berlin, Athens and Munich. Figure 4: Proportion of passenger kilometers travelled by car in Australian capital cities 1945 2007 Source: Bureau of Transport and Regional Economics (BTRE), 2007 Estimating urban traffic and congestion cost trends for Australian cities, Working Paper 71; BTRE unpublished dataa (1945 1976). Historical landuse planning perhaps also play a part in creating cities that are compact, thrive on public transport, walking and cycling and are accepting of congestion. It is easy to compare European
medieval cities grown from a walking 30 minute catchment with Brisbane and the Undue Subdivision of Land Prevention Act 1885. In reflecting on history, the shape of Brisbane city has been influenced by two factors: The provision of road based transport ;and Undue Subdivision of Land Prevention Act. The Undue Subdivision of Land Prevention Act 1885 was a law passed by the Parliament of Queensland to prevent overcrowding and urban degradation in cities and towns in Brisbane. The purpose of the law was to control the size of blocks as at the time it was believed that smaller block sizes (similar to those in Sydney and Melbourne) were a sign of lower socio economic standing. It was very successful in influencing the shape of Brisbane. The Act prevented subdivision to lots less than sixteen perches or approximately 400 square metres. The same time in Sydney and Melbourne lots were being subdivided to as small as 150 square metres. Many of the older suburbs of Brisbane are characterised by detached houses on regular lots generally with a frontage of 10m (half a chain) unlike the terrace housing characteristic of other comparable cities. During the same period, the first railway was constructed linking Ipswich to Roma Street. The result of the increased distances within the acceptable travel time could be considered as the primary drivers that led to the sprawl of Brisbane. Over the past 80 years, many major infrastructure investment programs have influenced the shape of Brisbane such as: The construction of the tram network through inner city suburbs of West end, Fortitude Valley, New Farm and Newstead in the early 1900 s. The Nerang Bridge built in 1925 and the access it provided for the motor vehicle The subsequent road bridges linking both sides of the Brisbane River More recent tunnel construction programs The last factor City Density The vehicle has obviously played a very significant role in city development. Even in developing cities as car ownership levels increase, similar patterns can be seen. In Australia, the rate of expansion in the urban footprint is greater than most European cities. Figure 5 shows the cities where density is greatest. Of note, Milan, Berlin and Munich all rate highest in terms of density, all have average travel speeds of around 30 32 km/h (as opposed to 40km/h in Brisbane) indicating congestion and all have public transport share at above 30%. The same 3 cities have medieval roots in planning.
Figure 5: population, city size and density 14,000 12,000 10,000 8,000 6,000 4,000 2,000 0 Population (000's) Surface Area (sq km) Pop. Density (inhabitants per sq km) Source: Millennium Cities in Study of European best practice in the delivery of integrated transport: report on stage 1 benchmarking Other points for consideration include: Smaller populations don t necessarily correlate to lower densities. Similarly, larger populations also don t automatically imply density Paris, Madrid and Barcelona. Cities with dense CBD environments don t necessarily have higher overall densities. Cities with higher employment opportunities within the CBD tend to have higher population densities. The 30minute catchment for Brisbane Understanding that the private vehicle is the primary mode leads to the need to understand how travel time relates to distance travelled. Assuming that the primary road based trip purpose is journey to work (say 60% of trips) and that these trips occur only on week days ay for 47 weeks per year, the average daily trip distance is around: 15,000 x 0.6 = 9000 km / year for journey to work 5 x 47 = 235 days per year 9000 / 235 = 38.3 km per day Average travel time on arterial roads = 40km/h Distance travelled in a day = 38.3 km Travel time to/from work = 57.4 mins / 2 = 29 mins in each direction
The 30 minute catchment for the Brisbane CBD, especially for the motor vehicle is large as shown in Figure 6. This is based on an average vehicle speed of 40km/h. It extends from Redcliffe / North Lakes in the north to Ipswich in the west and Ormeau in the south. This area represents the opportunity to increase population and housing choice to provide options for people to live in a desirable catchment area. Current land use planning for this zone is best embraced in the River City Blueprint where over the next 20 years 156,000 new dwellings will be required and an additional 200,000 jobs. Similar maps for the Gold Coast and Sunshine Coast as significant employment hubs would also provide guidance for population density increases to meet community convenience desires. Of note is the approximate travel catchment with a similar size to the City of Brisbane local government boundary. Figure 6: 30 minute vehicle Travel time catchment assuming average 40 km/h travel speed Source:30 minute city
For cycle and walking trips the catchments are much smaller as shown in Figure 7. These are the zones where planning policy should focus on developments with low parking provision as the motor vehicle is not as critical to access the journey to work. South Brisbane, Woolongabba and Fortitude Valley all fall within these precincts. Figure7: The 30 minute catchment for Brisbane CBD for pedestrians and cyclists. Conclusion The shape of cities is driven by the travel mode and choices the community makes. Cities characterised by high car ownership, extensive road infrastructure and investment and limited congestion are large, sprawled and perpetuate the use of the motor vehicle. In these cities the distances travelled in 30 minutes for the journey to work are large and accessible. In contrast small compact cities have lower car ownership, greater public transport or active (walking and cycling) and roads that are congested typifying the shorter distances that can be travelled in 30mins. These cities include places such as Sydney, Berlin and Athens. As the motor vehicle becomes more competitive against alternative modes, city shape and function changes. Brisbane is on the cusp of change and planning needs to respond to this. Congestion is increasing and the travel time catchment for journey to work is decreasing. This is a positive cycle towards more sustainable city outcomes that should be encouraged. In summary People have a desire to live near work as this is a trip most make every day. 30 minutes is the time we generally want to spend travelling to and from work. Congestion or travel speed and mode changes the 30 minute catchment. Providing housing choice in the 30 minute catchment will most likely satisfy long term community needs and is a good planning rule of thumb.
Larger populations don t necessarily lead to higher densities. Planning policy and infrastructure investment also has a role to play. History, particularly the 30 minute catchment for the walking mode has had a big impact on city densities