The Lancet urban design, transport and health Series, http://www.thelancet.com/series/urban-design is a series of papers discussing how the expected enlargement of cities should be managed to enable healthy communities. Mainly aimed at growing mega-cities the papers provide some useful background for the Resilient City theme being pursued by several organisations.
The three papers in the series are:
(1) City planning and population health: a global challenge,
(2) Land use, transport, and population health: estimating the health benefits of compact cities
These three papers explore the thesis that land-use and transport policies contribute to worldwide epidemics of injuries and non-communicable diseases through traffic exposure, noise, air pollution, social isolation, low physical activity, and sedentary behaviours. They argue that designing and building “compact cities” with good public transport where a higher fraction of journeys are by foot, on bicycle or on low-pollution public transport would result in a healthier population suffering less traffic trauma, less ill-health effects of sedentary lifestyles and less ill-health effects of poor air quality. There also believe that “compact cities” could optimise socialisation leading to happier as well as healthier cities.
The first paper identifies 3 regional and 5 local policies and practices which, they claim, can affect a wide range of health outcomes including non-communicable diseases such as obesity. These measures include:
- “Destination accessibility” which aims to have people’s place of work, shopping facilities and leisure facilities either within walking or cycling distance of home or linked by good public transport;
- “Demand Management” which makes the use of the private car harder by rationing parking spaces in the centres;
- “Urban design” which separates cars from pedestrians and cyclists, provides public open spaces near to housing and has transport hubs and schools within a 15 minute walk of homes.
- Public transport – bus stops within 400m and rail links within 800m of homes;
- Diversity – different density housing near to and on top of shops and services;
- Desirability – Neighbourhoods designed to be safe, attractive, and accessible; public transport that is convenient, affordable, frequent, safe, and comfortable.
It has a clever graphic on page 2915 (link here) showing how 8 urban system policies can be used to enhance liveability, health, wellbeing, and quality of life; social, health, and environmental equity and quality.
A number of indicators are suggested. These can be used to determine a city’s performance in these areas. Indicators include the extent of regulation, percentage of population living within a given range of public transport, percentage of people who can get to work within a given time without using their own car, percentage of green or open space within the city and measures of health of community members in terms of the prevalence of such things as respiratory illnesses and obesity.
The second paper speculates about the health benefits of a compact city by considering a number of cities around the world and modelling the impact of changes to the density and layout that reduce the number of car miles and increases walking, cycling and public transport usage. They argue that the sprawling residential only suburbs that are common in the USA, Australia and New Zealand mitigate against public transport and walking or cycling.
Data analysis and modelling was used to try to understand the relationship between the layout and distances involved in cities and the modes of transport used and then to try understand the impact on the environment and on health of those modes of transport. I was struck by the data presented in Table 1 which seems to show that walking and cycling in Boston is much safer than the same activities in London (based on deaths and injuries per 100 million kilometres). The paper presents tables of the changes in distances travelled by each mode of transport (Table 3) and of the health implications of this (Table 4) for an arbitrary change in urban density (+30%), land use diversity (+30%) and distance to public transport (-30%).
The third paper discusses how the research can be used to influence decision makers. It makes the point that research results are often expressed in ways that are inaccessible to decision makers and that research is only one of many determinants of policy. It suggests that better use of research findings would result from the adoption of a four step process: Undertake policy-relevant research, use research methods that policy makers understand and value, actively disseminate findings to policy makers and engage in advocacy. It suggests that teaming with policy makers at all stages is a good idea. It gives several examples of organisations that have adopted this form of conscious “research translation” to good effect in areas relating urban planning to health outcomes.