How Big is Sustainable? the Interaction Between Settlement Size and Travel Behaviour.
WILIAMS J and BANISTER D, University College London, UK
New housing requirements appear set to greatly alter the current urban geography of England over the next 20 years. The 1991 predictions suggest that between 1991 and 2016 the population in England will increase by 7.7% and number of households will incre
New housing requirements appear set to greatly alter the current urban geography of England over the next 20 years. The 1991 predictions suggest that between 1991 and 2016 the population in England will increase by 7.7% and number of households will increase by nearly 23%. This means that household size will decline by 12% from 2.47 to 2.17 persons per household and there will be a demand for 4.4 million new homes. See Breheny (1998) for a comprehensive analysis of these figures. This scale of construction may substantially alter the pattern of urban development, expanding on existing settlements and building new ones. This in turn may impact on travel patterns and accessibility of services and facilities.
This paper investigates the impact that urban form has on travel patterns and accessibility. More specifically, it studies the relationships between urban form, distance travelled, modal split, energy, consumption and access to facilities and services. It outlines current research into these relationships and suggests future housing strategies which may reduce travel and energy consumption, promote modal shift and increase accessibility. The paper reports on the work being carried out within the URBASSS Research Project (EPSRC Sustainable Cities Programme) which investigates the interrelationship between settlement size, travel patterns and accessibility of services and facilities.
A reduction in the transport sector's energy consumption and increased accessibility, can be achieved by controlling various aspects of urban form, for example through housing development strategies (Figure 1). The location of the new housing directly influences travel patterns, energy consumption and accessibility. It may also effect the ~oss resident population size and densities within an existing settlement which again may alter travel patterns, energy consumption and accessibility. The location of new housing also may effect proximity of housing to services and facilities, which further influences travel patterns and accessibility.
New housing developments located within existing urban areas encourages shorter trips, modal diversity, reduces energy consumption and increases access to services and facilities. Locating housing development on strategic transport networks generally increases travel and the modal split reflects the network type. Locating housing outside existing urban areas increases travel and reduces self-containment. The development of free-standing settlements generally increases travel (Table 1).
Association for European Transport