Resources and Mobility in Sustainable Urban Transport

It is often said that we live in a culture of mobility, and that we are dependent on cars to get where we need to go, or even to enjoy our leisure time. Breaking our dependence on motorised private vehicles, and starting to use mobility management and public transport, to a higher degree than we currently do, are key if were are to aim for an accessible world rather than a mobile world. If we have access to work and leisure time activities in close proximity to our homes, we do not need to be as mobile as we are right now and instead focus could be shifted towards developing other communication forms to allow us to work in a more virtual way. So, might increased accessibility save the world?

A common definition of accessibility is “…potential interactions between places…or importance of a place based on available sets of opportunity” (Boschmann & Kwan, 2008 p.149.). In this chapter, accessibility in a transport system will be defined as ease of reaching destinations or simply – availability of resources². Resources in this sense include everything from natural resources, capital, labour, commodities, services etc., and

2 This applies both to transports of goods as well as to transport of people. In practice, an urban area is more accessible than a rural or peripheral area regardless of the intensity of transport and infrastructure.

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in the urban context for example work places, shops, hotels, cinemas, restaurants, and even residential housing. Mobility in a transport system can be defined as access to the possibility to change spatial position or creating the means that make resources available.

A higher degree of mobility makes it is easier to reach a certain destination. Examples of very high mobility would thus be ports, airports, railways, and motorway junctions with unlimited means of transport, not necessarily in places with abundant resources. This would imply that accessibility is crucial for achieving attractiveness in urban areas by allowing citizens and visitors to reach desired destinations and resources. Furthermore, this means that accessibility and attractiveness both are integral parts in sustainable urban development.

In order to see what mix of mobility and resources could contribute to balanced accessibility, which in turn leads to increased attractiveness and sustainable urban development, one could depart from the conceptual node-place model based on the research of Professor Luca Bertolini of the University of Amsterdam. The node-place model was based upon a multi criteria analysis and was originally used for mapping and developing the public transport systems of Amsterdam and Utrecht. The model was comprised of numerous variables such as proximity to the transport system, the number of directions served, daily frequency, and amount of stations reached within 45 minutes.

This is the node factor. The place factor in the Bertolini model is related to the intensity of activities of a place, measured as e.g. number of work places, shops, restaurants, and hotels. Bertolini weighted and indexed these factors in order to see the relationship between railway stations and travellers in the two agglomerations. The weighting and indexing also meant that the same scale could be used on both axes. The weighted and indexed factors can be seen in relation to standard values (i.e. desired normative relations between factors) for the system that is being investigated.³ This implies that along a 45°

line in the node-place model the studied weighted and indexed factors for a certain place fulfil the desired norm and pertains to the standard value. This indicates for example that if we have standard values for place at index 0.4 and for node at 0.4 as well, you have the optimal mix of node and place, and you are in fact located on the diagonal line. This in turn means that the mix of node and place for a certain city or area is optimal, in the sense of ‘it’s as easy to get there as you would want it to be’. If the indexed values of node and place differ, we get a situation where we have either excess capacity in the system or an indication that we need to increase the capacity of e.g. public transport (Bertolini, 1999).

To be able to use the conceptual node-place model, the authors have adapted it to fit the purpose of this study and chapter. The thought put forth in this chapter is that an optimal mix of mobility and resources is vital to increase city attractiveness, accessibility, economic growth, and sustainable urban development. If we view mobility as nodes and resources as places, the two factors that can contribute to city attractiveness and accessibility, and assign these to the x- and y-axes, theoretically, a diagonal line would indicate a balance of resources in relation to mobility, and would contribute to sustainable urban growth. That however only holds true if both resources and mobility are weighted in accordance with what Bertolini did in his original model.

3 The standard values in per cent (%) of one facility in relation to another facility or factor indicate the optimal provision of the studied facility. Such a value is related to the probability function of utilisation. For bicycle parking in proximity to public transport stations, this standard value is for instance 10%, indicating that for every 100 commuters, the need for bicycle parking spots are 10.

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The adapted node-place model in Figure 2 shows us different ideal situations; the further along the diagonal line one reaches, the intensity and diversity of transport in urban areas is increased. Above and to the left of the diagonal line, we have a situation where mobility and infrastructure outweighs the need of transport in relation to resources – we have an excess of transport supply which, inevitably, leads to low load factors and non-effective transports. Below and to the right of the middle diagonal line, the situation is the opposite – the number of resources outweighs mobility and infrastructure. In this case we have a transport deficiency, implying that demand for transport is greater than the supply.

At the same time, as this is a place with a high level of resources like leisure time activities, work places, and residential housing, the deficiency will affect attractiveness negatively.

Figure 2: Sustainable attractiveness and accessibility as a function of mobility and resources

What we aim for is to find an optimal mix of resources and mobility that would position us along the diagonal line in the node-place model. Along this line transport supply is in long run equilibrium with transport demand, leading to attractiveness, accessibility, and sustainable urban development. In order for shops and businesses in the attractive urban areas to receive goods, new measures and correct infrastructure is needed for urban goods transports. How could this work in practice? One way of obtaining the optimal mix of mobility and resources in the urban environment, in order to achieve attractiveness and sustainable urban economic growth, could be found in new concepts for city goods logistics such as UCCs. In order to adapt a UCC to the needs, a first measure should be to identify those indicators⁴ for resources and mobility that are needed to be used in the Bertolini analogy in order to create the optimal mix. The Bertolini model would then be a useful tool for authorities as well as stakeholders, and would help to create legitimacy in decision-making.

4 A few examples of useful resource indicators could be; number and structure of shops, amount of goods delivered, number of residents, inhabitants in the area, visitors and tourists, hotels, restaurants and theatres.

On the mobility resource side we find flow of public and private transport, number and structure of transport companies and forwarders, fill rates, traffic and transport regulations, fuel in use, and infrastructure etc.

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