2.1

Demographic Changes

2.1.1

Whilst the cities have been growing at different rates, they are all facing similar demographic trends that have led to an increase in travel. The key issue is the decline in inner city populations as residents have moved out to the suburbs or small towns and villages beyond the built-up area. This has increased the distance people have to travel and dramatically increased their reliance on the car, often because there is no other means of getting to their destination.

2.1.2

As more people have moved into the suburbs, both from the inner city and outside the metropolitan area, the existing road and rail links have become overcrowded. Cities that have built new infrastructure have seen road space, in particular, fill up rapidly as people buy cars and travel more

2.1.3

London experienced some decline in inner city residents, but this has been reversed through improvements in the quality of the local environment, availability of housing and changes in public preferences. Other cities have seen much greater decline in the inner city and rapid growth in the suburbs. For example, between 1970 and 2000, the population of the Ville de Paris fell by 11%, but the surrounding Ile de France region grew by 30%, and the desire to slow this trend has led politicians to do more to enhance the attractiveness of urban neighbourhoods. Similarly in Tokyo, the inner city population has fallen by 8% and the suburbs have doubled and two-thirds of commuters travel for more than an hour to get to work (Figure 2.1).

Figure 2.1 – Growth in Metropolitan Populations

Source: Kenworthy and Laube 1991 and various city census

2.1.4

Other factors that affect the demand for travel include the age structure and household size. All the cities have been ageing; London, Rome, Singapore and Tokyo have the highest proportion of working age adults and it is this age group that travels the most and does the greatest mileage by car . In addition, households have been shrinking and London and Nottingham have amongst the smallest households in the sample. People in smaller households make more journeys for a number of reasons including their need to travel for social interaction, higher disposable income and fewer opportunities for combining journeys.

2.2

Land Use Patterns

2.2.1

Cities have spread to accommodate more households, jobs and other functions. Barcelona, Nottingham and Zurich are good exam-ples of where this expansion has been limited by planning policies that have ensured that new development occurred within the built-up area. These compact, dense cities now have the shortest journeys and the highest proportion of walking and cycling, but this success is being undermined in Zurich where new towns are being developed around the airport and to the north of the city. These have reasonably high densities and a mix of land uses to reduce the need to travel, and good suburban rail services which are well-used by commuters travelling into the city where there are strict parking controls. However, the lack of similar constraints in the new employment areas has led to a dramatic increase in traffic as city residents have begun driving out to their recently relocated jobs.

2.2.2

London and Madrid initially spread in a finger pattern along radial corridors and this meant that the volume of motorised travel increased, but people still had good access to public transport. More recently low-density development has occurred between the ‘spokes’ and this is harder to serve with cost-effective rail and bus services. Paris and Tokyo have implemented multi-centric planning policies by concentrating development in new centres within the metropolitan area. These are served by fast rail links and have attracted new residents by providing cheap fares; in Paris, employers pay half the cost of season tickets (Carte Orange) for their employees and contribute to public transport through a levy on businesses with six or more staff (Versement Transport), and in Tokyo, employers bear the full commuting costs of their employees and deduct these from their corporate income taxes.

2.2.3

A similar approach to focusing development on rail stations has been adopted in Singapore, but the new towns have a mix of housing, jobs and other functions and so people do not need to travel so much (Figure 2.2 overleaf). Perth is also trying to reduce its reliance on the car by intensifying development at suburban rail stations (known as transit-oriented developments). Perhaps surprisingly, the early examples have proved to be popular in a city that values its suburban lifestyle and free-moving road network.

2.2.4

In contrast, New York has spread into New York State and the surrounding states of New Jersey and Connecticut, while over 20% of jobs have remained in Manhattan’s central business district (CBD). The zoning laws have allowed very low density housing that cannot be served by efficient public transport. This has led to a very high dependency on car travel, long journeys (Figure 2.3) and severe peak period congestion on the approaches to New York City. Measures to reduce traffic at peak times, make better use of existing road space and encourage drivers onto public transport have been the central themes of the transport strategy.

Figure 2.2 – Density and Average Journey Length

Figure 2.3 – Motorised Travel by Mode

2.3

Provision of Infrastructure

Roads

2.3.1

Most cities have radial highway networks and they have been investing in high capacity, often tolled, strategic links that bypass suburban centres and converge on a series of ring roads. For example, 14 autoroutes converge on the eight-lane Boulevard Périphérique which circles the Ville de Paris and within the city limits the Boulevards Extérieurs provide an inner ring road with grade separated flyovers and under-passes at intersections. Madrid has two complete orbitals and two major bypasses around the south and east of the city, Barcelona has three ring roads, and both these cities have a programme to relocate inner ring roads underground to reduce the severance effects of these roads on local communities and create an opportunity for improving conditions for walking.

2.3.2

London has a comparable overall provision of roads (Figure 2.4), but the strategic links are mainly single carriageways that run through the suburban centres and there are few dedicated orbital links and this is true of most other UK cities.

Figure 2.4 - Roads per 1000 People

2.3.3

The lower capacity UK networks cannot accommodate such high volumes of traffic per kilometre (traffic intensity) as the planned multi-lane freeways and distributors roads in Paris and New York, for example, and they become congested sooner (as illustrated by Figures 2.5-2.6). However, the study has found that the availability of road space has also encouraged higher car ownership and more car use, which reinforces the need to reallocate road space to support public transport investment.

2.3.4

Whilst the chart data precedes the congestion charging scheme in London, the potential of road pricing is evident in the high traffic intensity yet above-average speed in Singapore. The Electronic Road Pricing (ERP) charges vary according to the average speed in the city centre and surrounding freeways and this has helped to manage traffic levels throughout the day.

Figure 2.5 - Traffic Intensity

Figure 2.6 - Average Traffic Speed

Public Transport

2.3.5

Unlike roads, rail does not provide basic access and the level of supply is a function of transport policies. Heavy rail systems have tended to result from previous policies, but in the World Cities, Paris and Tokyo have been building new links and network expansions (with the assistance of private sector funding), while London and New York have focused on maintaining and improving existing infrastructure. London still has the highest supply and density (Figure 2.7), because of its smaller metropolitan area and lower population density.

Figure 2.7 – Provision of rail (surface and metro lines)

2.3.6

Most of the other large cities and medium sized cities have also been investing heavily in rail-based improvements. For example, Rome has brought 170km of suburban rail track into operation and more than doubled the length of its metro (to 68.5km), Madrid has added 115km to its of metro, and Barcelona and Nottingham have new trams. These improvements have led to an increase in overall public transport patronage, but the increase in rail use has sometimes been at the expense of bus use.

2.3.7

All the cities have been refreshing their bus fleets, bringing in low-floor, low emission vehicles, and improving passenger information, but there have been varying levels of commitment to implementing bus priority measures. It is here that the UK cities are leading the way in improving the relative speed, reliability and attractiveness of buses, alongside Dublin, Paris and Singapore.

2.3.8

London has implemented 400 new or extended bus lanes as part of the Mayor’s Transport Strategy, and Nottingham has 14 priority corridors with served by ‘Go2’ buses operating at 10-minute or better headways and both cities have seen a substantial rise in patronage.

2.3.9

Dublin has implemented nine Quality Bus Corridors, Paris has reorganised its entire regional bus network and put 350km of bus lanes in the Ville de Paris, and Singapore has implemented 120km of lanes and priority at selected signals across the city state.

2.4

Growth in Car Ownership

2.4.1

Increasing affluence, suburban living and rising average journey lengths have contributed to the growth in car ownership in all the cities up to the 1990s. Since then, rapid growth has continued in cities like Madrid and Dublin where market forces have led to the construction of new housing on peripheral sites with no public transport provision. However, there has been some decline in London and New York because of various factors including the cost of fuel and insurance, congestion and a shortage of parking and improvement in alternative modes. There has also been some decline in car ownership in Singapore because of the purchase controls and high taxes (see panel).