Community Severance and Health: What Do We Actually Know?

Abstract

Community severance occurs where road traffic (speed or volume) inhibits access to goods, services, or people. Appleyard and Lintell's seminal study of residents of three urban streets in San Francisco found an inverse relationship between traffic and social contacts. The extent of social networks predicts unhealthy behaviors, poor health, and mortality; high rather than low social integration is associated with reduced mortality, with an effect size of similar magnitude to stopping smoking. Although community severance diminishes social contacts, the implications of community severance for morbidity and mortality have not been empirically established. Based on a systematic literature search, we discuss what is actually known about community severance. There is empirical evidence that traffic speed and volume reduces physical activity, social contacts, children's play, and access to goods and services. However, no studies have investigated mental or physical health outcomes in relation to community severance. While not designed specifically to do so, recent developments in road design may also ameliorate community severance.

Health impacts of the M74 urban motorway extension: a mixed-method natural experimental study

“…Although there is little direct evidence regarding the link between severance and mental or physical health outcomes, previous research does suggest that severance may contribute to reduced social interactions and active travel. 44 In this chapter so far, a number of factors relating to the new motorway itself, as well as to wider systems of change taking place in the case study areas, have been shown to contribute to a complex picture of what may be described as severance and connectivity. Rather than an unambiguous severing effect of the new motorway, participants described the M74 extension as, by turns, a force for both connection and severance.…”

“…Exposure to roads and traffic has been shown to contribute to noise disturbance and severance, whereby residents are separated from the amenities that they use (such as shops and parks) or their interpersonal networks and social contacts are disrupted. [42][43][44] Other studies indicate an association between noise disturbance from traffic 45 or living in industrial areas characterised by noise disturbance and air pollution 46 and poorer quality of life or well-being. Furthermore, providing new or improved major roads has been shown to increase traffic 47 and may contribute to making sedentary travel by car a more attractive option, 26 and more traffic in local streets may make it less safe and attractive for people to be physically active outdoors, thereby promoting increases in other more sedentary activities.…”

“…44 In this section, we consider the findings of our qualitative research in relation to the perceptions and experiences of the neighbourhoods.…”

“…It thereby adds to a small but growing body of evidence for the effects of changing the built environment on patterns of travel behaviour, physical activity, accidents and well-being, as called for in recent reviews arising from the policy, practice and research communities alike. 38,44,158 More specifically, it is the first study to have evaluated the effect of a new motorway on physical activity and sedentary behaviour, and it makes a particular contribution to our understanding of the impacts of new major road infrastructure by investigating changes in multiple related outcomes at both individual and population level.…”

Community Severance: Where Is It Found and at What Cost?

“…The review focuses on the physical effects of transport infrastructure and motorised traffic on people's mobility (physical ability to move around) and accessibility (ability to reach particular places), and not on the wider effects that stem from these. For example, this paper does not consider the extensive evidence of the negative impact of road traffic on public health (Mindell & Karlsen, 2012), social networks (Mullan, 2003;Sauter & Huettenmoser, 2008) and spatial segregation (King & Blackmore, 2013;Mitchell & Lee, 2014). The deterioration of physical conditions for walking mobility may also have local and non-local economic and environmental effects, if it leads to a shift to motorised modes of transport.…”