A new perspective on accessibility. Sustainable, personal and multimodal

How can the current urban mobility system in which private cars predominate be further developed such that access and sustainability are both improved? To achieve a sustainable and accessible city, is it better to invest in cars or in public transport and bikes? What does this mean for accessibility for various categories of people? These are the questions considered in this study. To address them, CE Delft and MOVE Mobility have applied a new multimodal transport model.

Why the need for a new method?
The methods traditionally used to assess improvements in accessibility have two drawbacks when it comes to answering the questions posed here. First, they work with a single measure of accessibility for all categories of people, making insufficient allowance for their varied capabilities. This we have resolved by developing a model working with various different categories. Second, the traditional  methods allow people to choose from among a limited number of transport modes, with cycling time to and from train stations being modelled only very coarsely. As a result, there is only very partial inclusion of the access benefits of multimodal transport chains. Our newly developed multimodal network incorporates not only motoring, cycling and walking, but also the public transport network and schedules between all the stops and stations in the Netherlands. In our new approach,  more sensible travel options can be examined for door-to-door trips for different categories of travellers. One advantage is that this creates a better handle on the synergy between cycling and public transport, a key feature of this study.

Innovative approach works
Using the newly developed multimodal transport model a quantitative comparison was made between a mobility system geared primarily to improving car access and a system whereby new investments are directed first of all to improving public-transport and cycling access. This approach proved to work well and yield important insights for government investment in access improvement.

Selected conclusions:

• Future autonomous deterioration of car access can be compensated by means of investments in the car grid to a limited extent only.
• Investments in cycling and public transport have indirect positive effects for motorists: more people will opt for cycling and/or public transport, freeing up more space for motorists who have no alternatives, or do not wish to use the available alternatives.
• In all the cases examined, investing in improved public transport and cycling provisions have considerably more impact and are more cost-effective than investments in car transport.